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Sample records for aaa rupture risk

  1. Biomechanical rupture risk assessment of abdominal aortic aneurysms based on a novel probabilistic rupture risk index.

    PubMed

    Polzer, Stanislav; Gasser, T Christian

    2015-12-01

    A rupture risk assessment is critical to the clinical treatment of abdominal aortic aneurysm (AAA) patients. The biomechanical AAA rupture risk assessment quantitatively integrates many known AAA rupture risk factors but the variability of risk predictions due to model input uncertainties remains a challenging limitation. This study derives a probabilistic rupture risk index (PRRI). Specifically, the uncertainties in AAA wall thickness and wall strength were considered, and wall stress was predicted with a state-of-the-art deterministic biomechanical model. The discriminative power of PRRI was tested in a diameter-matched cohort of ruptured (n = 7) and intact (n = 7) AAAs and compared to alternative risk assessment methods. Computed PRRI at 1.5 mean arterial pressure was significantly (p = 0.041) higher in ruptured AAAs (20.21(s.d. 14.15%)) than in intact AAAs (3.71(s.d. 5.77)%). PRRI showed a high sensitivity and specificity (discriminative power of 0.837) to discriminate between ruptured and intact AAA cases. The underlying statistical representation of stochastic data of wall thickness, wall strength and peak wall stress had only negligible effects on PRRI computations. Uncertainties in AAA wall stress predictions, the wide range of reported wall strength and the stochastic nature of failure motivate a probabilistic rupture risk assessment. Advanced AAA biomechanical modelling paired with a probabilistic rupture index definition as known from engineering risk assessment seems to be superior to a purely deterministic approach. PMID:26631334

  2. New developments in the treatment of ruptured AAA.

    PubMed

    Tsilimparis, Nikolaos; Saleptsis, Vasileios; Rohlffs, Fiona; Wipper, Sabine; Debus, Eike S; Kölbel, Tilo

    2016-04-01

    Ruptured Abdominal Aortic Aneurysms (rAAA) represent the most common abdominal aortic emergency with an incidence of 6.3 per 100,000 inhabitants whereas the incidence of rAAA in the population over 65 years was 35.5/100.000 inhabitants. Early suspicion and diagnosis of rAAA is essential for good outcomes and over the past decades a great variety of perioperative management concepts, techniques and materials have been implemented to further improve the outcomes of this acute and life-threatening disease. Corner-stones for the improvement of outcomes include the introduction of management protocols for rAAA, the principle of hypotensive hemostasis and the introduction of endovascular techniques as well as the improved anesthesia and postoperative intensive care therapy with early identification and management of devastating complications such as the abdominal compartment syndrome. While the role of endovascular aortic repair in rAAA is not yet answered, it appears to be very promising especially in the presence of new techniques that could resolve a number of the problems restricting success of EVAR in rAAAs. PMID:26784556

  3. Relative importance of aneurysm diameter and body size for predicting AAA rupture in men and women

    PubMed Central

    Lo, Ruby C.; Lu, Bing; Fokkema, Margriet T.M.; Conrad, Mark; Patel, Virendra I.; Fillinger, Mark; Matyal, Robina; Schermerhorn, Marc L.

    2014-01-01

    Objectives Women have been shown to have up to a four-fold higher risk of abdominal aortic aneurysm (AAA) rupture at any given aneurysm diameter compared to men, leading to recommendations to offer repair to women at lower diameter thresholds. Although this higher risk of rupture may simply reflect greater relative aortic dilatation in women who have smaller aortas to begin with, this has never been quantified. Our objective was therefore to quantify the relationship between rupture and aneurysm diameter relative to body size and to determine whether a differential association between aneurysm diameter, body size, and rupture risk exists for men and women. Methods We performed a retrospective review of all patients in the Vascular Study Group of New England (VSGNE) database who underwent endovascular or open AAA repair. Using each patient’s height and weight, body mass index (BMI) and body surface area (BSA) were calculated. Next, indices of each measure of body size (height, weight, BMI, BSA) relative to aneurysm diameter were calculated for each patient. To generate these indices, we divided aneurysm diameter (in cm) by the measure of body size [e.g. aortic size index (ASI) = aneurysm diameter (cm) / BSA (m2)]. Along with other relevant clinical variables, we used these indices to construct different age-adjusted and multivariable-adjusted logistic regression models to determine predictors of ruptured repair vs. elective repair. Models for men and women were developed separately and different models were compared using the area under the curve (AUC). Results We identified 4045 patients who underwent AAA repair (78% male, 53% EVAR). Women had significantly smaller diameter aneurysms, lower BSA, and higher BSA indices than men (Table 1). For men, the variable that increased the odds of rupture the most was aneurysm diameter (AUC = 0.82). Men exhibited an increased rupture risk with increasing aneurysm diameter (<5.5cm: OR 1.0; 5.5–6.4cm: OR 0.9, 95% CI 0.5–1

  4. The Role of Geometric and Biomechanical Factors in Abdominal Aortic Aneurysm Rupture Risk Assessment

    PubMed Central

    Raut, Samarth S.; Chandra, Santanu; Shum, Judy; Finol, Ender A.

    2013-01-01

    The current clinical management of abdominal aortic aneurysm (AAA) disease is based to a great extent on measuring the aneurysm maximum diameter to decide when timely intervention is required. Decades of clinical evidence show that aneurysm diameter is positively associated with the risk of rupture, but other parameters may also play a role in causing or predisposing the AAA to rupture. Geometric factors such as vessel tortuosity, intraluminal thrombus volume, and wall surface area are implicated in the differentiation of ruptured and unruptured AAAs. Biomechanical factors identified by means of computational modeling techniques, such as peak wall stress, have been positively correlated with rupture risk with a higher accuracy and sensitivity than maximum diameter alone. The objective of this review is to examine these factors, which are found to influence AAA disease progression, clinical management and rupture potential, as well as to highlight on-going research by our group in aneurysm modeling and rupture risk assessment. PMID:23508633

  5. Rescue EVAR for ruptured AAA: Clinical success does not mean technical success.

    PubMed

    Setacci, Francesco; Sirignano, Pasqualino; de Donato, Gianmarco; Galzerano, Giuseppe; Setacci, Carlo

    2014-10-01

    We report a clinical evolution of a 85-years old male admitted to our Emergency Department for ruptured abdominal aortic aneurysm (rAAA). One month later a huge type I proximal endoleak was detected and corrected by proximal aortic extension. We decided to fix the stent-graft to the aortic wall using EndoAnchors. However, an asymptomatic type III endoleak due to controlateral limb disconnection was detected at the followed schedulated CT angio and corrected by a relining of the endograft. The patient is now in good clinical condition with no evidence of endoleaks at 1-year follow-up. PMID:24347133

  6. Diagnosis and perioperative management of ruptured AAA mimicking symptomatic groin hernia

    PubMed Central

    Klein, Holger Jan; Becker, Daniel; Rancic, Zoran

    2015-01-01

    Introduction Ruptured abdominal aortic aneurysm (RAAA) can infrequently present as symptomatic groin hernia. This misleading form of presentation often leads to erroneous preoperative management resulting in poor survival. Case presentation Two patients with RAAA mimicking symptomatic groin hernia underwent different preoperative managements pointing out the importance of the principles of hypotensive haemostasis in the scope of this emergency scenario. Conclusion Computed Tomography Angiography (CTA) remains the recommended diagnostic tool—for both safe diagnosis of the ruptured aneurysm and precise preoperative planning. Endovascular aortic repair of the RAAA—if feasible—is the treatment of choice. This rare form of RAAA manifestation should call physicians attention—especially in patients with known abdominal aortic aneurysms in their preceding medical history. PMID:26656148

  7. Risk Profiles for Aortic Dissection and Ruptured or Surgically Treated Aneurysms: A Prospective Cohort Study

    PubMed Central

    Landenhed, Maya; Engström, Gunnar; Gottsäter, Anders; Caulfield, Michael P.; Hedblad, Bo; Newton‐Cheh, Christopher; Melander, Olle; Smith, J. Gustav

    2015-01-01

    Background Community screening to guide preventive interventions for acute aortic disease has been recommended in high‐risk individuals. We sought to prospectively assess risk factors in the general population for aortic dissection (AD) and severe aneurysmal disease in the thoracic and abdominal aorta. Methods and Results We studied the incidence of AD and ruptured or surgically treated aneurysms in the abdominal (AAA) or thoracic aorta (TAA) in 30 412 individuals without diagnosis of aortic disease at baseline from a contemporary, prospective cohort of middle‐aged individuals, the Malmö Diet and Cancer study. During up to 20 years of follow‐up (median 16 years), the incidence rate per 100 000 patient‐years at risk was 15 (95% CI 11.7 to 18.9) for AD, 27 (95% CI 22.5 to 32.1) for AAA, and 9 (95% CI 6.8 to 12.6) for TAA. The acute and in‐hospital mortality was 39% for AD, 34% for ruptured AAA, and 41% for ruptured TAA. Hypertension was present in 86% of individuals who subsequently developed AD, was strongly associated with incident AD (hazard ratio [HR] 2.64, 95% CI 1.33 to 5.25), and conferred a population‐attributable risk of 54%. Hypertension was also a risk factor for AAA with a smaller effect. Smoking (HR 5.07, 95% CI 3.52 to 7.29) and high apolipoprotein B/A1 ratio (HR 2.48, 95% CI 1.73 to 3.54) were strongly associated with AAA and conferred a population‐attributable risk of 47% and 25%, respectively. Smoking was also a risk factor for AD and TAA with smaller effects. Conclusions This large prospective study identified distinct risk factor profiles for different aortic diseases in the general population. Hypertension accounted for more than half of the population risk for AD, and smoking for half of the population risk of AAA. PMID:25609416

  8. Adipocyte in vascular wall can induce the rupture of abdominal aortic aneurysm

    PubMed Central

    Kugo, Hirona; Zaima, Nobuhiro; Tanaka, Hiroki; Mouri, Youhei; Yanagimoto, Kenichi; Hayamizu, Kohsuke; Hashimoto, Keisuke; Sasaki, Takeshi; Sano, Masaki; Yata, Tatsuro; Urano, Tetsumei; Setou, Mitsutoshi; Unno, Naoki; Moriyama, Tatsuya

    2016-01-01

    Abdominal aortic aneurysm (AAA) is a vascular disease involving the gradual dilation of the abdominal aorta. It has been reported that development of AAA is associated with inflammation of the vascular wall; however, the mechanism of AAA rupture is not fully understood. In this study, we investigated the mechanism underlying AAA rupture using a hypoperfusion-induced animal model. We found that the administration of triolein increased the AAA rupture rate in the animal model and that the number of adipocytes was increased in ruptured vascular walls compared to non-ruptured walls. In the ruptured group, macrophage infiltration and the protein levels of matrix metalloproteinases 2 and 9 were increased in the areas around adipocytes, while collagen-positive areas were decreased in the areas with adipocytes compared to those without adipocytes. The administration of fish oil, which suppresses adipocyte hypertrophy, decreased the number and size of adipocytes, as well as decreased the risk of AAA rupture ratio by 0.23 compared to the triolein administered group. In human AAA samples, the amount of triglyceride in the adventitia was correlated with the diameter of the AAA. These results suggest that AAA rupture is related to the abnormal appearance of adipocytes in the vascular wall. PMID:27499372

  9. Adipocyte in vascular wall can induce the rupture of abdominal aortic aneurysm.

    PubMed

    Kugo, Hirona; Zaima, Nobuhiro; Tanaka, Hiroki; Mouri, Youhei; Yanagimoto, Kenichi; Hayamizu, Kohsuke; Hashimoto, Keisuke; Sasaki, Takeshi; Sano, Masaki; Yata, Tatsuro; Urano, Tetsumei; Setou, Mitsutoshi; Unno, Naoki; Moriyama, Tatsuya

    2016-01-01

    Abdominal aortic aneurysm (AAA) is a vascular disease involving the gradual dilation of the abdominal aorta. It has been reported that development of AAA is associated with inflammation of the vascular wall; however, the mechanism of AAA rupture is not fully understood. In this study, we investigated the mechanism underlying AAA rupture using a hypoperfusion-induced animal model. We found that the administration of triolein increased the AAA rupture rate in the animal model and that the number of adipocytes was increased in ruptured vascular walls compared to non-ruptured walls. In the ruptured group, macrophage infiltration and the protein levels of matrix metalloproteinases 2 and 9 were increased in the areas around adipocytes, while collagen-positive areas were decreased in the areas with adipocytes compared to those without adipocytes. The administration of fish oil, which suppresses adipocyte hypertrophy, decreased the number and size of adipocytes, as well as decreased the risk of AAA rupture ratio by 0.23 compared to the triolein administered group. In human AAA samples, the amount of triglyceride in the adventitia was correlated with the diameter of the AAA. These results suggest that AAA rupture is related to the abnormal appearance of adipocytes in the vascular wall. PMID:27499372

  10. Serum angiotensin-converting enzyme 2 is an independent risk factor for in-hospital mortality following open surgical repair of ruptured abdominal aortic aneurysm

    PubMed Central

    Nie, Wanpin; Wang, Yan; Yao, Kai; Wang, Zheng; Wu, Hao

    2016-01-01

    Open surgical repair (OSR) is a conventional surgical method used in the repair a ruptured abdominal aortic aneurysm (AAA); however, OSR results in high perioperative mortality rates. The level of serum angiotensin-converting enzyme 2 (ACE2) has been reported to be an independent risk factor for postoperative in-hospital mortality following major cardiopulmonary surgery. In the present study, the association of serum ACE2 levels with postoperative in-hospital mortality was investigated in patients undergoing OSR for ruptured AAA. The study enrolled 84 consecutive patients underwent OSR for ruptured AAA and were subsequently treated in the intensive care unit. Patients who succumbed postoperatively during hospitalization were defined as non-survivors. Serum ACE2 levels were measured in all patients prior to and following the surgery using ELISA kits. The results indicated that non-survivors showed significantly lower mean preoperative and postoperative serum ACE2 levels when compared with those in survivors. Multivariate logistic regression analysis also showed that, subsequent to adjusting for potential confounders, the serum ACE2 level on preoperative day 1 showed a significant negative association with the postoperative in-hospital mortality. This was confirmed by multivariate hazard ratio analysis, which showed that, subsequent to adjusting for the various potential confounders, the risk of postoperative in-hospital mortality remained significantly higher in the two lowest serum ACE2 level quartiles compared with that in the highest quartile on preoperative day 1. In conclusion, the present study provided the first evidence supporting that the serum ACE2 level is an independent risk factor for the in-hospital mortality following OSR for ruptured AAA. Furthermore, low serum ACE2 levels on preoperative day 1 were found to be associated with increased postoperative in-hospital mortality. Therefore, the serum ACE2 level on preoperative day 1 may be a potential

  11. Determining the influence of calcification on the failure properties of abdominal aortic aneurysm (AAA) tissue.

    PubMed

    O'Leary, Siobhan A; Mulvihill, John J; Barrett, Hilary E; Kavanagh, Eamon G; Walsh, Michael T; McGloughlin, Tim M; Doyle, Barry J

    2015-02-01

    Varying degrees of calcification are present in most abdominal aortic aneurysms (AAAs). However, their impact on AAA failure properties and AAA rupture risk is unclear. The aim of this work is evaluate and compare the failure properties of partially calcified and predominantly fibrous AAA tissue and investigate the potential reasons for failure. Uniaxial mechanical testing was performed on AAA samples harvested from 31 patients undergoing open surgical repair. Individual tensile samples were divided into two groups: fibrous (n=31) and partially calcified (n=38). The presence of calcification was confirmed by fourier transform infrared spectroscopy (FTIR). A total of 69 mechanical tests were performed and the failure stretch (λf), failure stress (σf) and failure tension (Tf) were recorded for each test. Following mechanical testing, the failure sites of a subset of both tissue types were examined using scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy (EDS) to investigate the potential reasons for failure. It has been shown that the failure properties of partially calcified tissue are significantly reduced compared to fibrous tissue and SEM and EDS results suggest that the junction between a calcification deposit and the fibrous matrix is highly susceptible to failure. This study implicates the presence of calcification as a key player in AAA rupture risk and provides further motivation for the development of non-invasive methods of measuring calcification. PMID:25482218

  12. Comparison of the strain field of abdominal aortic aneurysm measured by magnetic resonance imaging and stereovision: a feasibility study for prediction of the risk of rupture of aortic abdominal aneurysm.

    PubMed

    Wang, Yufei; Joannic, David; Delassus, Patrick; Lalande, Alain; Juillion, Patrick; Fontaine, Jean-François

    2015-04-13

    The prediction of the risk of rupture of abdominal aortic aneurysm (AAA) is a complex problem. Currently the criteria to predict rupture of abdominal aortic aneurysms are aneurysm diameter and growth rates. It is generally believed that study of the wall strain distribution could be helpful to find a better decision criterion for surgery of aortic aneurysms before their rupture. The wall strain distribution depends on many biological and biomechanical factors such as elastic properties of the aorta, turbulent blood flow, anatomy of the aorta, presence of thrombus or not and so on. Recently, numerical simulations to estimate rupture-potential have received many attentions. However, none of the medical imaging tools for screening and monitoring of AAAs were studied in terms of mechanical behavior and experimentally to demonstrate their capability to measure relevant variables. The aim of this study was to develop a metrological approach for deployment testing of the ability of techniques for measuring local in-vitro deformations based on comparison of stereovision and MRI. In this paper, we present the implementation approach and results of the study based on cylindrical phantoms with or without AAA representing, respectively, healthy and unhealthy artery. Through this study, an experimental device was developed for the behavior study of AAA during a cardiac cycle. The results show that the stereovision techniques used in laboratory is well suited and is qualitatively and quantitatively equivalent with MRI measurements. PMID:25661521

  13. Morphology Parameters for Intracranial Aneurysm Rupture Risk Assessment

    PubMed Central

    Dhar, Sujan; Tremmel, Markus; Mocco, J; Kim, Minsuok; Yamamoto, Junichi; Siddiqui, Adnan H.; Hopkins, L. Nelson; Meng, Hui

    2008-01-01

    OBJECTIVE The aim of this study is to identify image-based morphological parameters that correlate with human intracranial aneurysm (IA) rupture. METHODS For 45 patients with terminal or sidewall saccular IAs (25 unruptured, 20 ruptured), three-dimensional geometries were evaluated for a range of morphological parameters. In addition to five previously studied parameters (aspect ratio, aneurysm size, ellipticity index, nonsphericity index, and undulation index), we defined three novel parameters incorporating the parent vessel geometry (vessel angle, aneurysm [inclination] angle, and [aneurysm-to-vessel] size ratio) and explored their correlation with aneurysm rupture. Parameters were analyzed with a two-tailed independent Student's t test for significance; significant parameters (P < 0.05) were further examined by multivariate logistic regression analysis. Additionally, receiver operating characteristic analyses were performed on each parameter. RESULTS Statistically significant differences were found between mean values in ruptured and unruptured groups for size ratio, undulation index, nonsphericity index, ellipticity index, aneurysm angle, and aspect ratio. Logistic regression analysis further revealed that size ratio (odds ratio, 1.41; 95% confidence interval, 1.03−1.92) and undulation index (odds ratio, 1.51; 95% confidence interval, 1.08−2.11) had the strongest independent correlation with ruptured IA. From the receiver operating characteristic analysis, size ratio and aneurysm angle had the highest area under the curve values of 0.83 and 0.85, respectively. CONCLUSION Size ratio and aneurysm angle are promising new morphological metrics for IA rupture risk assessment. Because these parameters account for vessel geometry, they may bridge the gap between morphological studies and more qualitative location-based studies. PMID:18797347

  14. Risk of cerebral arteriovenous malformation rupture during pregnancy and puerperium

    PubMed Central

    Wang, Shuo; Zhao, Yuan-li; Teo, Mario; Guo, Peng; Zhang, Dong; Wang, Rong; Cao, Yong; Ye, Xun; Kang, Shuai

    2014-01-01

    Objective: To determine whether the risk of arteriovenous malformation (AVM) rupture is increased during pregnancy and puerperium. Methods: Participants included 979 female patients with intracranial AVM admitted to Beijing Tiantan Hospital between 1960 and 2010. Two neurosurgery residents reviewed medical records for each case. Of them, 393 patients with ruptured AVM between 18 and 40 years of age were used for case-crossover analysis. Number of children born and clinical information during pregnancy and puerperium were retrieved to identify whether AVM rupture occurred during this period. Results: Of the 979 women, 797 hemorrhages occurred during 25,578 patient-years of follow-up, yielding an annual hemorrhage rate of 3.11%. The annual AVM hemorrhage rate in patients aged 18 to 40 years (n = 579) was 2.78%, lower than the rate in other age groups (odds ratio = 0.75, 95% confidence interval 0.65–0.86, p < 0.05). Of the 393 patients with rupture of AVM aged 18 to 40 years, 12 hemorrhages occurred in 12 patients over 452 pregnancies, yielding a hemorrhage rate of 2.65% per pregnancy or 3.32% per year. Among the remaining 381 patients, 441 hemorrhages occurred during 10,627 patient-years of follow-up, yielding an annual hemorrhage rate of 4.14%. The odds ratio for rupture of AVM during pregnancy and puerperium, compared with the control period, was 0.71 (95% confidence interval 0.61–0.82). Conclusions: No increased risk of hemorrhage was found in patients with cerebral AVM during pregnancy and the puerperium. We therefore would not advise against pregnancy in women with intracranial AVM. PMID:24759847

  15. Abdominal Aortic Aneurysms and Risk Factors for Adverse Events.

    PubMed

    Ahmed, Raheel; Ghoorah, Kuldeepa; Kunadian, Vijay

    2016-01-01

    An abdominal aortic aneurysm (AAA) is a focal full thickness dilatation of the abdominal aorta, greater than 1.5 times its normal diameter. Although some patients with AAA experience back or abdominal pain, most remain asymptomatic until rupture. The prognosis after AAA rupture is poor. Management strategies for patients with asymptomatic AAAs include risk factor reduction, such as smoking cessation, optimizing antihypertensive treatment, and treating dyslipidemia, as well as surveillance by ultrasound. Currently, aneurysm diameter alone is often used to assess risk of rupture. Once the aneurysm diameter reaches 5.5 cm, the risk of rupture is considered greater than the risk of intervention and elective aneurysm repair is undertaken. There is increasing interest in detecting AAAs early, and national screening programs are now in place. Furthermore, there is increasing research interest in biomarkers, genetics, and functional imaging to improve detection of AAAs at risk of progression and rupture. In this review, we discuss risk factors for AAA rupture, which should be considered during the management process, to advance current deficiencies in management pathways. PMID:25580705

  16. 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, ...

  17. Radiographic Risk Factors for Contralateral Rupture in Dogs with Unilateral Cranial Cruciate Ligament Rupture

    PubMed Central

    Chuang, Connie; Ramaker, Megan A.; Kaur, Sirjaut; Csomos, Rebecca A.; Kroner, Kevin T.; Bleedorn, Jason A.; Schaefer, Susan L.; Muir, Peter

    2014-01-01

    Background Complete cranial cruciate ligament rupture (CR) is a common cause of pelvic limb lameness in dogs. Dogs with unilateral CR often develop contralateral CR over time. Although radiographic signs of contralateral stifle joint osteoarthritis (OA) influence risk of subsequent contralateral CR, this risk has not been studied in detail. Methodology/Principal Findings We conducted a retrospective longitudinal cohort study of client-owned dogs with unilateral CR to determine how severity of radiographic stifle synovial effusion and osteophytosis influence risk of contralateral CR over time. Detailed survival analysis was performed for a cohort of 85 dogs after case filtering of an initial sample population of 513 dogs. This population was stratified based on radiographic severity of synovial effusion (graded on a scale of 0, 1, and 2) and severity of osteophytosis (graded on a scale of 0, 1, 2, and 3) of both index and contralateral stifle joints using a reproducible scoring method. Severity of osteophytosis in the index and contralateral stifles was significantly correlated. Rupture of the contralateral cranial cruciate ligament was significantly influenced by radiographic OA in both the index and contralateral stifles at diagnosis. Odds ratio for development of contralateral CR in dogs with severe contralateral radiographic stifle effusion was 13.4 at one year after diagnosis and 11.4 at two years. Odds ratio for development of contralateral CR in dogs with severe contralateral osteophytosis was 9.9 at one year after diagnosis. These odds ratios were associated with decreased time to contralateral CR. Breed, age, body weight, gender, and tibial plateau angle did not significantly influence time to contralateral CR. Conclusion Subsequent contralateral CR is significantly influenced by severity of radiographic stifle effusion and osteophytosis in the contralateral stifle, suggesting that synovitis and arthritic joint degeneration are significant factors in the

  18. Risk of rupture of unruptured cerebral aneurysms in elderly patients

    PubMed Central

    Date, Isao; Tokunaga, Koji; Tominari, Shinjiro; Nozaki, Kazuhiko; Shiokawa, Yoshiaki; Houkin, Kiyohiro; Murayama, Yuichi; Ishibashi, Toshihiro; Takao, Hiroyuki; Kimura, Toshikazu; Nakayama, Takeo; Morita, Akio

    2015-01-01

    Objectives: The aim of this study was to identify risk factors for rupture of unruptured cerebral aneurysms (UCAs) in elderly Japanese patients aged 70 years or older. Methods: The participants included all patients 70 years of age or older in 3 prospective studies in Japan (the Unruptured Cerebral Aneurysm Study of Japan [UCAS Japan], UCAS II, and the prospective study at the Jikei University School of Medicine). A total of 1,896 patients aged 70 years or older with 2,227 UCAs were investigated. The median and mean follow-up periods were 990 and 802.7 days, respectively. Results: The mean aneurysm size was 6.2 ± 3.9 mm. Sixty-eight patients (3.6%) experienced subarachnoid hemorrhage during the follow-up period. Multivariable analysis per patient revealed that in patients aged 80 years or older (hazard ratio [HR], 2.02; 95% confidence interval [CI], 1.16–3.49, p = 0.012), aneurysms 7 mm or larger (HR, 3.08; 95% CI, 1.35–7.03, p = 0.007 for 7–9 mm; HR, 7.82; 95% CI, 3.60–16.98, p < 0.001 for 10–24 mm; and HR, 43.31; 95% CI, 12.55–149.42, p < 0.001 for ≥25 mm) and internal carotid–posterior communicating artery aneurysms (HR, 2.45; 95% CI, 1.23–4.88, p = 0.011) were independent predictors for UCA rupture in elderly patients. Conclusions: In our pooled analysis of prospective cohorts in Japan, patient age and aneurysm size and location were significant risk factors for UCA rupture in elderly patients. PMID:26511450

  19. Non-invasive in vivo time-dependent strain measurement method in human abdominal aortic aneurysms: Towards a novel approach to rupture risk estimation.

    PubMed

    Nagy, Róbert; Csobay-Novák, Csaba; Lovas, Attila; Sótonyi, Péter; Bojtár, Imre

    2015-07-16

    We aim to introduce a novel, inverse method for in vivo material parameter identification of human abdominal aortic aneurysms (AAA), which could overcome one of the greatest sources of uncertainty in patient-specific simulations, and could also serve as a rapid, patient-calibrated, novel measure of aneurysm rupture risk. As an initial step, the determination of the kinematic fields is presented here. Images of the AAA lumen, acquired in 10 discrete time-steps through a stabilized cardiac cycle by electrocardiogram-gated computer tomography angiography, are used to approximate the in vivo, time dependent kinematic fields of the arterial wall using a novel, incompressible Kirchhoff-Love shell element implemented into the isogeometric analysis framework. Defining a smoothing parametric surface via 2D bicubic spline fitting in the spatial, and by harmonic regression in the temporal domain, we are able to adequately mitigate the measurement inaccuracy. The ill-posedness of the problem requires certain assumptions on the displacement. In our case, based on numerical fluid structure interaction simulation observations, we hypothesized the incremental displacement vector of the reference surface to coincide with its corrected normal; hence the periodic movement was assured. Finally, we present two examples: an AAA and an undilated calcificated aorta. Strains in the diseased part were compared to those in a healthy arterial section of the same patient and found to have significant differences in both specimens. In the case of AAAs, high spatial gradients surrounding the dilated part indicate abrupt changes in material properties, a phenomenon less significant for the atherosclerotic case. PMID:25980555

  20. AAAS: Politics. . . and Science

    ERIC Educational Resources Information Center

    Science News, 1978

    1978-01-01

    Reviews topics discussed during the American Association for the Advancement of Science (AAAS) meeting held in Washington, D.C. Topics included: the equal rights amendment, laetrile, nuclear radiation hazards, sociobiology, and various science topics. (SL)

  1. Propose a Wall Shear Stress Divergence to Estimate the Risks of Intracranial Aneurysm Rupture

    PubMed Central

    Zhang, Y.; Takao, H.; Murayama, Y.; Qian, Y.

    2013-01-01

    Although wall shear stress (WSS) has long been considered a critical indicator of intracranial aneurysm rupture, there is still no definite conclusion as to whether a high or a low WSS results in aneurysm rupture. The reason may be that the effect of WSS direction has not been fully considered. The objectives of this study are to investigate the magnitude of WSS (|WSS|) and its divergence on the aneurysm surface and to test the significance of both in relation to the aneurysm rupture. Patient-specific computational fluid dynamics (CFD) was used to compute WSS and wall shear stress divergence (WSSD) on the aneurysm surface for nineteen patients. Our results revealed that if high |WSS| is stretching aneurysm luminal surface, and the stretching region is concentrated, the aneurysm is under a high risk of rupture. It seems that, by considering both direction and magnitude of WSS, WSSD may be a better indicator for the risk estimation of aneurysm rupture (154). PMID:24191140

  2. A Review of Computational Methods to Predict the Risk of Rupture of Abdominal Aortic Aneurysms

    PubMed Central

    Canchi, Tejas; Kumar, S. D.; Ng, E. Y. K.; Narayanan, Sriram

    2015-01-01

    Computational methods have played an important role in health care in recent years, as determining parameters that affect a certain medical condition is not possible in experimental conditions in many cases. Computational fluid dynamics (CFD) methods have been used to accurately determine the nature of blood flow in the cardiovascular and nervous systems and air flow in the respiratory system, thereby giving the surgeon a diagnostic tool to plan treatment accordingly. Machine learning or data mining (MLD) methods are currently used to develop models that learn from retrospective data to make a prediction regarding factors affecting the progression of a disease. These models have also been successful in incorporating factors such as patient history and occupation. MLD models can be used as a predictive tool to determine rupture potential in patients with abdominal aortic aneurysms (AAA) along with CFD-based prediction of parameters like wall shear stress and pressure distributions. A combination of these computer methods can be pivotal in bridging the gap between translational and outcomes research in medicine. This paper reviews the use of computational methods in the diagnosis and treatment of AAA. PMID:26509168

  3. Labor Dystocia and the Risk of Uterine Rupture in Women with Prior Cesarean.

    PubMed

    Vachon-Marceau, Chantale; Demers, Suzanne; Goyet, Martine; Gauthier, Robert; Roberge, Stéphanie; Chaillet, Nils; Laroche, Jasmin; Bujold, Emmanuel

    2016-05-01

    Objective The objective of this study was to evaluate the association between labor dystocia and uterine rupture. Methods We performed a secondary analysis of a multicenter case-control study that included women with single, prior, low-transverse cesarean section who experienced complete uterine rupture during a trial of labor (TOL). For each case, three women who underwent a TOL without uterine rupture were selected as controls. Data were collected on cervical dilatations from admission to delivery. We evaluated the relationship between uterine rupture and labor dystocia according to several criteria, including the World Health Organization's (WHO's) partogram. Results Data were available for 90 cases and 260 controls. Compared with the controls, uterine rupture was associated with less cervical dilatation on admission, slower cervical dilatation in the first stage of labor and longer second stage of labor (all with p < 0.05). Performing cesarean when the labor curve crossed the ACTION line of WHO's partogram or when the second stage was greater than 2 hours could have (1) prevented up to 56% of uterine rupture and (2) reduced the duration of labor in 57% of women with failed TOL. Conclusion Labor dystocia is a significant risk factor for uterine rupture. Labor progression should be assessed regularly in women with prior cesarean. PMID:26731182

  4. Differentiation, self-other representations, and rupture-repair processes: Predicting child maltreatment-risk

    PubMed Central

    Skowron, Elizabeth A.; Kozlowski, JoEllen M.; Pincus, Aaron L.

    2010-01-01

    This set of studies was designed to examine the relational underpinnings of child abuse potential in a sample of 51 urban families. In Study 1, lower maternal differentiation of self—most notably, greater emotional reactivity and greater emotional cutoff—along with self-attacking introjects, together distinguished mothers at higher risk (vs. lower risk) for child maltreatment (CM). In Study 2, patterns of interactive rupture and repair were examined in a subsample of n = 15 families and found to vary as a function of risk for CM. Specifically, SASB coding (Benjamin, 1996, 2003) of mother-children interactions during two moderately stressful lab tasks revealed higher rates of interactive mismatch and mother-initiated ruptures, and fewer successful repairs in families at higher-risk-for-CM, relative to families at lower-risk. Implications for counseling and directions for further translational research are discussed. PMID:20729978

  5. Nominations sought for AAAS award

    NASA Astrophysics Data System (ADS)

    The American Association for the Advancement of Science seeks nominations for its Award for International Scientific Cooperation, which recognizes an individual or small group for outstanding contributions to furthering international cooperation in science or engineering.AAAS presents this award in collaboration with its affiliated organizations in the AAAS Consortium of Affiliates for International Programs. A prize of $2,500, a certificate of citation, and travel expenses to the AAAS annual meeting to receive the award are included.

  6. [Ultrasound screening for abdominal aortic aneurysms - a rational measure to prevent sudden rupture].

    PubMed

    Torsello, Giovanni; Debus, Eike Sebastian; Schmitz-Rixen, Thomas; Grundmann, Reinhart Thomas

    2016-07-01

    The ruptured abdominal aortic aneurysm (AAA) has still a high hospital mortality rate of about 50 % (intervention and non-corrective treatment combined). With an easy non-invasive and inexpensive measure such as the ultrasound screening rupture threatened aneurysms can be recognized in time and then treated prophylactically, hemorrhagic shock can be avoided. Screening programs in England and Sweden currently describe an AAA prevalence of 1.5 % among screened 65-year-old males. With an absolute risk reduction for aneurysm-related death of 15.1 per 10,000 men invited for screening and a cost of £ 7,370 per quality-adjusted life year (QALY), screening for this target group is highly cost-effective. Comprehensive AAA screening requires defined criteria for the quality of the aortic ultrasound examination and for the surgical treatment of detected large AAA. These interventions should be concentrated in centers obligated to quality registry documentation. Patients with smaller AAA, requiring no repair, should be included in a surveillance program, also with registry of their long-term data. PMID:27404935

  7. Risk of Hemorrhage in Combined Neuroform Stenting and Coil Embolization of Acutely Ruptured Intracranial Aneurysms

    PubMed Central

    Jankowitz, B.; Thomas, A.J.; Vora, N.; Gupta, R.; Levy, E.; Yamamoto, J.; Kassam, A.; Gologorsky, Y.; Panapitiya, N.; Sandhu, E.; Crago, E.; Hricik, A.; Lee, K.; Gallek, M.; Jovin, T.; Horowitz, M.

    2008-01-01

    Summary Stenting as adjuvant therapy for the coiling of acutely ruptured aneurysms remains controversial due to the necessity of anticoagulation and antiplatelet medications. We report our experience using the Neuroform stent in the management of 41 aneurysms in 40 patients over a period of three years. For aneurysms whose open surgical risk remains excessive with a morphology that would preclude complete embolization, the risks of stenting may be warranted. PMID:20557738

  8. Sexual Activity as a Risk Factor for the Spontaneous Rupture of Cerebral Aneurysms.

    PubMed

    Blanke-Roeser, Constantin; Matschke, Jakob; Püschel, Klaus

    2016-06-01

    Subarachnoid hemorrhages from ruptured cerebral aneurysms have a high clinical relevance and often lead to death. Approximately 2% to 5% of the people worldwide, even of younger age, are said to have aneurysms at cerebral arteries. In many cases, they remain clinically unapparent for decades. However, there are numerous risk factors for the rupture of an aneurysm, including temporary raises of the blood pressure. Such changes of the blood pressure can be induced even by several everyday behaviors. For example, any sort of sexual activities may cause extensive raises of the blood pressure because of several physical and psychological factors. The term "sexual activity" covers sexual intercourse as well as masturbation. In this article, the remarkable case of a 24-year-old woman with a ruptured cerebral aneurysm in the context of masturbation is presented. It is discussed with respect to the possible pathophysiological effects of sexual activity on cerebral aneurysms. PMID:27043460

  9. Prevalence of previously undiagnosed abdominal aortic aneurysms in the area of Como: the ComoCuore "looking for AAA" ultrasonography screening.

    PubMed

    Corrado, Giovanni; Durante, Alessandro; Genchi, Vincenzo; Trabattoni, Loris; Beretta, Sandro; Rovelli, Enza; Foglia-Manzillo, Giovanni; Ferrari, Giovanni

    2016-08-01

    The prognosis for abdominal aortic aneurysm (AAA) rupture is poor. Long-term follow-up of population-based randomized trials has demonstrated that ultrasound (US) screening for abdominal aortic aneurysms (AAAs) measuring 3 cm or greater decreases AAA-related mortality rates and is cost-effective. We though to prospectively perform during a 26-month period a limited US examination of the infrarenal aorta in volunteers of both gender aged 60-85 years without history of AAA living in the area of Como, Italy. From September 2010 to November 2013 ComoCuore, a no-profit nongovernmental association, enrolled 1555 people (aged 68.8 ± 6.8 years; 48.6 % males). Clinical data and a US imaging of the aorta were collected for each participant. AAA was found in 22 volunteers (1.4 %) mainly males (2.5 % in males vs. 0.4 % in females p = 0.005). Overall, the prevalence of cardiovascular risk factors was higher in patients with vs. without AAA (mean 2.9 ± 3.0 vs. 1.4 ± 1.0 respectively, p < 0.0001). Independent predictors of AAA on multivariate analysis were age (OR 1.14, 1.06-1.22; p < 0.0001), male gender (OR 8.23, 1.79-37.91; p = 0.007), and both current (OR 4.98, 1.57-15.79; p = 0.007) and previous smoking (OR 2.76, 1.12-8.94; p = 0.03). Our study confirms the feasibility of one time US screening for AAA in a large cohort of asymptomatic people. Independent predictors of AAA were male sex, older age and a history of smoking. Accordingly to recent data the prevalence of AAA seems to be declining, maybe due to a reduction of smoking in Italy. PMID:27215751

  10. Risk functions for human and porcine eye rupture based on projectile characteristics of blunt objects.

    PubMed

    Kennedy, Eric A; Ng, Tracy P; McNally, Craig; Stitzel, Joel D; Duma, Stephan M

    2006-11-01

    Eye ruptures are among the most devastating eye injuries and can occur in automobile crashes, sporting impacts, and military events, where blunt projectile impacts to the eye can be encountered. The purpose of this study was to develop injury risk functions for globe rupture of both human and porcine eyes from blunt projectile impacts. This study was completed in two parts by combining published eye experiments with new test data. In the first part, data from 57 eye impact tests that were reported in the literature were analyzed. Projectile characteristics such as mass, cross-sectional area, and velocity, as well as injury outcome were noted for all tests. Data were sorted by species type and areas were identified where a paucity of data existed, based on the kinetic and normalized energy of assaulting objects. For the second part, a total of 126 projectile tests were performed on human and porcine eyes. Projectiles used for these tests included blunt aluminum projectiles, BBs, foam pellets, Airsoft pellets, and paintballs. Data for each projectile were recorded prior to testing and high-speed video was used to determine projectile velocity prior to striking the eye. In part three the data were pooled for a total of 183 eye impact tests, 83 human and 100 porcine, and were analyzed to develop the injury risk criteria. Binary logistic regression was used to develop injury risk functions based on kinetic and normalized energy. Probit analysis was used to estimate confidence intervals for the injury risk functions. Porcine eyes were found to be significantly stronger than human eyes in resisting globe rupture (p=0.01). For porcine eyes a 50% risk of globe rupture was found to be 71,145 J/m2, with a confidence interval of 63,245 J/m2 to 80,390 J/m2. Human eyes were found to have a 50% risk of globe rupture at a lower, 35,519 J/m2, with confidence intervals of 32,018 J/m2 to 40,641 J/m2. The results presented in this paper are useful in estimating the risk of globe

  11. Risk assessment and risk scores in the management of aortic aneurysms.

    PubMed

    Von Meijenfeldt, Gerdine C I; Van Der Laan, Maarten J; Zeebregts, Clark J; Balm, Ron; Verhagen, Hence J M

    2016-04-01

    The decision whether to operate a patient or not can be challenging for a clinician for both ruptured abdominal aortic aneurysms (AAAs) as well as elective AAAs. Prior to surgical intervention it would be preferable that the clinician exactly knows which clinical variables lower or increase the chances of morbidity and mortality postintervention. To help in the preoperative counselling and shared decision making several clinical variables can be identified as risk factors and with these, risk models can be developed. An ideal risk score for aneurysm repair includes routinely obtained physiological and anatomical variables, has excellent discrimination and calibration, and is validated in different geographical areas. For elective AAA repair, several risk scores are available, for ruptured AAA treatment, these scores are far less well developed. In this manuscript, we describe the designs and results of published risk scores for elective and open repair. Also, suggestions for uniformly reporting of risk factors and their statistical analyses are described. Furthermore, the preliminary results of a new risk model for ruptured aortic aneurysm will be discussed. This score identifies age, hemoglobin, cardiopulmonary resuscitation and preoperative systolic blood pressure as risk factors after multivariate regression analysis. This new risk score can help to identify patients that would not benefit from repair, but it can also potentially identify patients who would benefit and therefore lower turndown rates. The challenge for further research is to expand on validation of already existing promising risk scores in order to come to a risk model with optimal discrimination and calibration. PMID:26698033

  12. Development and Analysis of Synthetic Composite Materials Emulating Patient AAA Wall Material Properties

    NASA Astrophysics Data System (ADS)

    Margossian, Christa M.

    Abdominal Aortic Aneurysm (AAA) rupture accounts for 14,000 deaths a year in the United States. Since the number of ruptures has not decreased significantly in recent years despite improvements in imaging and surgical procedures, there is a need for an accurate, noninvasive technique capable of establishing rupture risk for specific patients and discriminating lesions at high risk. In this project, synthetic composite materials replicating patient-specific wall stiffness and strength were developed and their material properties evaluated. Composites utilizing various fibers were developed to give a range of stiffness from 1825.75 kPa up through 8187.64 kPa with one base material, Sylgard 170. A range of strength from 631.12 kPa to 1083 kPa with the same base material was also found. By evaluating various base materials and various reinforcing fibers, a catalogue of stiffnesses and strengths was started to allow for adaptation to specific patient properties. Three specific patient properties were well-matched with two composites fabricated: silk thread-reinforced Sylgard 170 and silk thread-reinforced Dragon Skin 20. The composites showed similar stiffnesses to the specific patients while reaching target stresses at particular strains. Not all patients were matched with composites as of yet, but recommendations for future matches are able to be determined. These composites will allow for the future evaluation of flow-induced wall stresses in models replicating patient material properties and geometries.

  13. Interactions between collagen gene variants and risk of anterior cruciate ligament rupture.

    PubMed

    O'Connell, Kevin; Knight, Hayley; Ficek, Krzysztof; Leonska-Duniec, Agata; Maciejewska-Karlowska, Agnieszka; Sawczuk, Marek; Stepien-Slodkowska, Marta; O'Cuinneagain, Dion; van der Merwe, Willem; Posthumus, Michael; Cieszczyk, Pawel; Collins, Malcolm

    2015-01-01

    The COL5A1 and COL12A1 variants are independently associated with modulating the risk of anterior cruciate ligament (ACL) rupture in females. The objective of this study was to further investigate if COL3A1 and COL6A1 variants independently, as well as, collagen gene-gene interactions, modulate ACL rupture risk. Three hundred and thirty-three South African (SA, n = 242) and Polish (PL, n = 91) participants with diagnosed ACL ruptures and 378 controls (235 SA and 143 PL) were recruited. Participants were genotyped for COL3A1 rs1800255 G/A, COL5A1 rs12722 (T/C), COL6A1 rs35796750 (T/C) and COL12A1 rs970547 (A/G). No significant associations were identified between COL6A1 rs35796750 and COL3A1 rs1800255 genotypes and risk of ACL rupture in the SA cohort. The COL3A1 AA genotype was, however, significantly (p = 0.036) over-represented in the PL ACL group (9.9%, n = 9) when compared to the PL control (CON) group (2.8%, n = 4). Although there were genotype distribution differences between the SA and PL cohorts, the T+A-inferred pseudo-haplotype constructed from COL5A1 and COL12A1 was significantly over-represented in the female ACL group when compared to the female CON group within the SA (T+A ACL 50.5%, T+A CON 38.1%, p = 0.022), PL (T+A ACL 56.3%, T+A CON 36.3%, p = 0.029) and combined (T+A ACL 51.8%, T+A CON 37.5%, p = 0.004) cohorts. In conclusion, the novel main finding of this study was a significant interaction between the COL5A1 rs12722 T/C and COL12A1 rs970547 A/G variants and risk of ACL injury. These results highlight the importance of investigating gene-gene interactions in the aetiology of ACL ruptures in multiple independent cohorts. PMID:25073002

  14. Sac Angiography and Glue Embolization in Emergency Endovascular Aneurysm Repair for Ruptured Abdominal Aortic Aneurysm

    SciTech Connect

    Koike, Yuya Nishimura, Jun-ichi Hase, Soichiro Yamasaki, Motoshige

    2015-04-15

    PurposeThe purpose of this study was to demonstrate a sac angiography technique and evaluate the feasibility of N-butyl cyanoacrylate (NBCA) embolization of the ruptured abdominal aortic aneurysm (AAA) sac in emergency endovascular aneurysm repair (EVAR) in hemodynamically unstable patients.MethodsA retrospective case series of three patients in whom sac angiography was performed during emergency EVAR for ruptured AAA was reviewed. After stent graft deployment, angiography within the sac of aneurysm (sac angiography) was performed by manually injecting 10 ml of contrast material through a catheter to identify the presence and site of active bleeding. In two patients, sac angiography revealed active extravasation of the contrast material, and NBCA embolization with a coaxial catheter system was performed to achieve prompt sealing.ResultsSac angiography was successful in all three patients. In the two patients who underwent NBCA embolization for aneurysm sac bleeding, follow-up computed tomography (CT) images demonstrated the accumulation of NBCA consistent with the bleeding site in preprocedural CT images.ConclusionsEVAR is associated with a potential risk of ongoing bleeding from type II or IV endoleaks into the disrupted aneurysm sac in patients with severe coagulopathy. Therefore, sac angiography and NBCA embolization during emergency EVAR may represent a possible technical improvement in the treatment of ruptured AAA in hemodynamically unstable patients.

  15. Endovascular approach for ruptured abdominal aortic aneursyms.

    PubMed

    Setacci, F; Sirignano, P; De Donato, G; Chisci, E; Galzerano, G; Cappelli, A; Palasciano, G; Setacci, C

    2010-06-01

    The rupture of an abdominal aortic aneurysm (rAAA) causes about 15000 deaths/year in the USA alone. Even though over the last 50 years progress in surgical techniques and in postoperative intensive care have been outstanding, the analysis of registries has shown either no decrease in the mortality rate for surgically treated rAAAs. Some reports asserted better out come for endovascular repair (EVAR) compared with surgery in case of rAAA. Despite this evidence, EVAR for rAAA remains prerogative of few centers worldwide. In conclusion only larger study or registry could assest the real role of EVAR in the management of rAAA. PMID:20523280

  16. The AAA+ superfamily of functionally diverse proteins

    PubMed Central

    Snider, Jamie; Thibault, Guillaume; Houry, Walid A

    2008-01-01

    The AAA+ superfamily is a large and functionally diverse superfamily of NTPases that are characterized by a conserved nucleotide-binding and catalytic module, the AAA+ module. Members are involved in an astonishing range of different cellular processes, attaining this functional diversity through additions of structural motifs and modifications to the core AAA+ module. PMID:18466635

  17. DNA Repair Gene Polymorphism and the Risk of Mitral Chordae Tendineae Rupture

    PubMed Central

    Kalayci Yigin, Aysel; Bulent Vatan, Mehmet; Akdemir, Ramazan; Necati Murat Aksoy, Muhammed; Cakar, Mehmet Akif; Kilic, Harun; Erkorkmaz, Unal; Karacan, Keziban; Kaleli, Suleyman

    2015-01-01

    Polymorphisms in Lys939Gln XPC gene may diminish DNA repair capacity, eventually increasing the risk of carcinogenesis. The aim of the present study was to evaluate the significance of polymorphism Lys939Gln in XPC gene in patients with mitral chordae tendinea rupture (MCTR). Twenty-one patients with MCTR and thirty-seven age and sex matched controls were enrolled in the study. Genotyping of XPC gene Lys939Gln polymorphism was carried out using polymerase chain reaction- (PCR-) restriction fragment length polymorphism (RFLP). The frequencies of the heterozygote genotype (Lys/Gln-AC) and homozygote genotype (Gln/Gln-CC) were significantly different in MCTR as compared to control group, respectively (52.4% versus 43.2%, p = 0.049; 38.15% versus 16.2%, p = 0.018). Homozygote variant (Gln/Gln) genotype was significantly associated with increased risk of MCTR (OR = 2.059; 95% CI: 1.097–3.863; p = 0.018). Heterozygote variant (Lys/Gln) genotype was also highly significantly associated with increased risk of MCTR (OR = 1.489; 95% CI: 1.041–2.129; p = 0.049). The variant allele C was found to be significantly associated with MCTR (OR = 1.481; 95% CI: 1.101–1.992; p = 0.011). This study has demonstrated the association of XPC gene Lys939Gln polymorphism with MCTR, which is significantly associated with increased risk of MCTR. PMID:26604426

  18. Risk assessment of severe accident-induced steam generator tube rupture

    SciTech Connect

    1998-03-01

    This report describes the basis, results, and related risk implications of an analysis performed by an ad hoc working group of the U.S. Nuclear Regulatory Commission (NRC) to assess the containment bypass potential attributable to steam generator tube rupture (SGTR) induced by severe accident conditions. The SGTR Severe Accident Working Group, comprised of staff members from the NRC`s Offices of Nuclear Reactor Regulation (NRR) and Nuclear Regulatory Research (RES), undertook the analysis beginning in December 1995 to support a proposed steam generator integrity rule. The work drew upon previous risk and thermal-hydraulic analyses of core damage sequences, with a focus on the Surry plant as a representative example. This analysis yielded new results, however, derived by predicting thermal-hydraulic conditions of selected severe accident scenarios using the SCDAP/RELAP5 computer code, flawed tube failure modeling, and tube failure probability estimates. These results, in terms of containment bypass probability, form the basis for the findings presented in this report. The representative calculation using Surry plant data indicates that some existing plants could be vulnerable to containment bypass resulting from tube failure during severe accidents. To specifically identify the population of plants that may pose a significant bypass risk would require more definitive analysis considering uncertainties in some assumptions and plant- and design-specific variables. 46 refs., 62 figs., 37 tabs.

  19. Increased 18F-FDG Uptake Is Predictive of Rupture in a Novel Rat Abdominal Aortic Aneurysm Rupture Model

    PubMed Central

    English, Sean J.; Piert, Morand R.; Diaz, Jose A.; Gordon, David; Ghosh, Abhijit; D'Alecy, Louis G.; Whitesall, Steven E.; Sharma, Ashish K.; DeRoo, Elise P.; Watt, Tessa; Su, Gang; Henke, Peter K.; Eliason, Jonathan L.; Ailawadi, Gorav; Upchurch, Gilbert R.

    2015-01-01

    Objective To determine whether 18F-fluorodeoxyglucose (18F-FDG) micro–positron emission tomography (micro-PET) can predict abdominal aortic aneurysm (AAA) rupture. Background An infrarenal AAA model is needed to study inflammatory mechanisms that drive rupture. 18F-FDG PET can detect vascular inflammation in animal models and patients. Methods After exposing Sprague-Dawley rats to intra-aortic porcine pancreatic elastase (PPE) (12 U/mL), AAA rupture was induced by daily, subcutaneous, β-aminopropionitrile (BAPN, 300 mg/kg, N = 24) administration. Negative control AAA animals (N = 15) underwent daily saline subcutaneous injection after PPE exposure. BAPN-exposed animals that did not rupture served as positive controls [nonruptured AAA (NRAAA) 14d, N = 9]. Rupture was witnessed using radiotelemetry. Maximum standard uptakes for 18F-FDG micro-PET studies were determined. Aortic wall PAI-1, uPA, and tPA concentrations were determined by western blot analyses. Interleukin (IL)-1β, IL-6, IL-10, and MIP-2 were determined by Bio-Plex bead array. Neutrophil and macrophage populations per high-power field were quantified. Matrix metalloproteinase (MMP) activities were determined by zymography. Results When comparing ruptured AAA (RAAA) to NRAAA 14d animals, increased focal 18F-FDG uptakes were detected at subsequent sites of rupture (P = 0.03). PAI-1 expression was significantly less in RAAA tissue (P = 0.01), with comparable uPA and decreased tPA levels (P = 0.02). IL-1β (P = 0.04), IL-6 (P = 0.001), IL-10 (P = 0.04), and MIP-2 (P = 0.02)expression, neutrophil (P = 0.02) and macrophage presence (P = 0.002), and MMP9 (P < 0.0001) activity were increased in RAAA tissue. Conclusions With this AAA rupture model, increased prerupture 18F-FDG uptake on micro-PET imaging was associated with increased inflammation in the ruptured AAA wall. 18F-FDG PET imaging may be used to monitor inflammatory changes before AAA rupture. PMID:24651130

  20. Ruptured eardrum

    MedlinePlus

    Tympanic membrane perforation; Eardrum - ruptured or perforated; Perforated eardrum ... Buttaravoli P, Leffler SM. Perforated tympanic membrane (ruptured eardrum). ... PA: Mosby Elsevier; 2012:chap 37. Kerschner JE. Otitis ...

  1. Quantifying Earthquake Collapse Risk of Tall Steel Braced Frame Buildings Using Rupture-to-Rafters Simulations

    NASA Astrophysics Data System (ADS)

    Mourhatch, Ramses

    This thesis examines collapse risk of tall steel braced frame buildings using rupture-to-rafters simulations due to suite of San Andreas earthquakes. Two key advancements in this work are the development of (i) a rational methodology for assigning scenario earthquake probabilities and (ii) an artificial correction-free approach to broadband ground motion simulation. The work can be divided into the following sections: earthquake source modeling, earthquake probability calculations, ground motion simulations, building response, and performance analysis. As a first step the kinematic source inversions of past earthquakes in the magnitude range of 6-8 are used to simulate 60 scenario earthquakes on the San Andreas fault. For each scenario earthquake a 30-year occurrence probability is calculated and we present a rational method to redistribute the forecast earthquake probabilities from UCERF to the simulated scenario earthquake. We illustrate the inner workings of the method through an example involving earthquakes on the San Andreas fault in southern California. Next, three-component broadband ground motion histories are computed at 636 sites in the greater Los Angeles metropolitan area by superposing short-period (0.2s-2.0s) empirical Green's function synthetics on top of long-period (> 2.0s) spectral element synthetics. We superimpose these seismograms on low-frequency seismograms, computed from kinematic source models using the spectral element method, to produce broadband seismograms. Using the ground motions at 636 sites for the 60 scenario earthquakes, 3-D nonlinear analysis of several variants of an 18-story steel braced frame building, designed for three soil types using the 1994 and 1997 Uniform Building Code provisions and subjected to these ground motions, are conducted. Model performance is classified into one of five performance levels: Immediate Occupancy, Life Safety, Collapse Prevention, Red-Tagged, and Model Collapse. The results are combined with

  2. Endoluminal Treatment of Ruptured Abdominal Aortic Aneurysm with Small Intestinal Submucosa Sandwich Endografts: A Pilot Study in Sheep

    SciTech Connect

    Yamada, Katsuyuki; Pavcnik, Dusan; Uchida, Barry T.; Timmermans, Hans A.; Corless, Christopher L.; Yin, Qiang; Yamakado, Koichiro; Wha Park, Joong; Roesch, Josef; Keller, Frederick S.; Sato, Morio; Yamada, Ryusaku

    2001-03-15

    Purpose: To evaluate efficacy of small intestinal submucosa (SIS) Sandwich endografts for the treatment of acute rupture of abdominal aortic aneurysms (AAA) and to explore the short-term reaction of the aorta to this material.Methods: In eight adult sheep, an infrarenal AAA was created transluminally by dilation of a short Palmaz stent. In six sheep, the aneurysm was then ruptured by overdilation of the stent with a large angioplasty balloon. Two sheep with AAAs that were not ruptured served as controls. A SIS Sandwich endograft, consisting of a Z stent frame with 5 bodies and covered inside and out with SIS, was used to exclude the ruptured and non-ruptured AAAs. Follow-up aortography was done immediately after the procedure and before sacrifice at 4, 8, or 12 weeks. Autopsy and histologic studies followed.Results: Endograft placement was successful in all eight sheep. Both ruptured and non-ruptured AAAs were successfully excluded. Three animals with AAA rupture developed hind leg paralysis due to compromise of the arterial supply to the lower spinal cord and were sacrificed 1 day after the procedure. In five animals, three with rupture and two controls, follow-up aortograms revealed no aortic stenoses and no perigraft leaks. Gross and histologic studies revealed incorporation of the endografts into the aortic wall with replacement of SIS by dense neointima that was completely endothelialized in areas where the endograft was in direct contact with the aortic wall. In central portions of the endograft, in contact with the thrombosed aneurysm, endothelialization was incomplete even at 12 weeks.Conclusion: The SIS Sandwich endografts effectively excluded simple AAAs and ruptured AAAs. They were rapidly incorporated into the aortic wall. A detailed long-term study is warranted.

  3. Rupture processes of the 2015 Mw 7.9 Gorkha earthquake and its Mw 7.3 aftershock and their implications on the seismic risk

    NASA Astrophysics Data System (ADS)

    Liu, Chengli; Zheng, Yong; Wang, Rongjiang; Shan, Bin; Xie, Zujun; Xiong, Xiong; Ge, Can

    2016-07-01

    The rupture processes of the 2015 April 25 Gorkha earthquake and its strongest aftershock occurred on May 12 in Nepal are investigated by joint inversion of seismological and geodetic data. Synthetic test shows that the sedimentary layers in the source region play an important role in the rupture process inversion. Our optimized model of the mainshock shows that the rupture has a unilateral propagation pattern. The dominant mechanism is pure thrust with maximum slip of 5.8 m, the rupture scale extends ~ 60 km along dip and ~ 150 km along strike, and the largest static stress change is ~ 7.6 MPa. The total seismic moment is 7.87 × 1020 N m, equivalent to Mw 7.9. Most seismic moment was released within 80 s and the majority seismic moment was released at the first 40 s. The rupture propagated in main slip asperity with a velocity of ~ 3.0 km/s. The strong aftershock magnitude is about Mw 7.3, and the peak slip is about 5.0 m, close to the peak slip of the mainshock. Moreover, the slips of the mainshock and the aftershocks are in good complementary, suggesting a triggering relationship between them. Considering the strain accumulation, the Gorkha earthquake ruptured only part of the seismic gap alone, thus still poses high earthquake risk, especially in the west side of the mainshock rupture zone.

  4. Genetic analysis of abdominal aortic aneurysms (AAA)

    SciTech Connect

    St. Jean, P.L.; Hart, B.K.; Zhang, X.C.

    1994-09-01

    The association between AAA and gender, smoking (SM), hypertension (HTN) and inguinal herniation (IH) was examined in 141 AAA probands and 139 of their 1st degree relatives with aortic exam (36 affected, 103 unaffected). There was no significant difference between age at diagnosis of affecteds and age at exam of unaffecteds. Of 181 males, 142 had AAA; of 99 females, 35 had AAA. Using log-linear modeling AAA was significantly associated at the 5% level with gender, SM and HTN but not IH. The association of AAA with SM and HTN held when males and females were analyzed separately. HTN was -1.5 times more common in both affected males and females, while SM was 1.5 and 2 times more common in affected males and females, respectively. Tests of association and linkage analyses were performed with relevant candidate genes: 3 COL3A1 polymorphisms (C/T, ALA/THR, AvaII), 2 ELN polymorphisms (SER/GLY, (CA)n), FBN1(TAAA)n, 2 APOB polymorphisms (Xbal,Ins/Del), CLB4B (CA)n, PI and markers D1S243 (CA)n, HPR (CA)n and MFD23(CA)n. The loci were genotyped in > 100 AAA probands and > 95 normal controls. No statistically significant evidence of association at the 5% level was obtained for any of the loci using chi-square test of association. 28 families with 2 or more affecteds were analyzed using the affected pedigree member method (APM) and lod-score analyses. There was no evidence for linkage with any loci using APM. Lod-score analysis under an autosomal recessive model resulted in excluding linkage (lod score < -2) of all loci to AAA at {theta}=0.0. Under an autosomal dominant model, linkage was excluded at {theta}=0.0 to ELN, APOB, CLG4B, D1S243, HPR and MFD23. The various genes previously proposed in AAA pathogenesis are neither associated nor casually related in our study population.

  5. LMIP/AAA: Local Authentication, Authorization and Accounting (AAA) Protocol for Mobile IP

    NASA Astrophysics Data System (ADS)

    Chenait, Manel

    Mobile IP represents a simple and scalable global mobility solution. However, it inhibits various vulnerabilities to malicious attacks and, therefore, requires the integration of appropriate security services. In this paper, we discuss two authentication schemes suggested for Mobile IP: standard authentication and Mobile IP/AAA authentication. In order to provide Mobile IP roaming services including identity verication, we propose an improvement to Mobile/AAA authentication scheme by applying a local politic key management in each domain, hence we reduce hando latency by avoiding the involvement of AAA infrastructure during mobile node roaming.

  6. Sequence analysis of the AAA protein family.

    PubMed Central

    Beyer, A.

    1997-01-01

    The AAA protein family, a recently recognized group of Walker-type ATPases, has been subjected to an extensive sequence analysis. Multiple sequence alignments revealed the existence of a region of sequence similarity, the so-called AAA cassette. The borders of this cassette were localized and within it, three boxes of a high degree of conservation were identified. Two of these boxes could be assigned to substantial parts of the ATP binding site (namely, to Walker motifs A and B); the third may be a portion of the catalytic center. Phylogenetic trees were calculated to obtain insights into the evolutionary history of the family. Subfamilies with varying degrees of intra-relatedness could be discriminated; these relationships are also supported by analysis of sequences outside the canonical AAA boxes: within the cassette are regions that are strongly conserved within each subfamily, whereas little or even no similarity between different subfamilies can be observed. These regions are well suited to define fingerprints for subfamilies. A secondary structure prediction utilizing all available sequence information was performed and the result was fitted to the general 3D structure of a Walker A/GTPase. The agreement was unexpectedly high and strongly supports the conclusion that the AAA family belongs to the Walker superfamily of A/GTPases. PMID:9336829

  7. Differentiation, Self-Other Representations, and Rupture-Repair Processes: Predicting Child Maltreatment Risk

    ERIC Educational Resources Information Center

    Skowron, Elizabeth A.; Kozlowski, JoEllen M.; Pincus, Aaron L.

    2010-01-01

    This set of studies was designed to examine the relational underpinnings of child abuse potential in a sample of 51 urban families. In Study 1, lower maternal differentiation of self--most notably, greater emotional reactivity and greater emotional cutoff--along with self-attacking introjects distinguished mothers at higher risk (vs. lower risk)…

  8. Rupture disc

    DOEpatents

    Newton, Robert G.

    1977-01-01

    The intermediate heat transport system for a sodium-cooled fast breeder reactor includes a device for rapidly draining the sodium therefrom should a sodium-water reaction occur within the system. This device includes a rupturable member in a drain line in the system and means for cutting a large opening therein and for positively removing the sheared-out portion from the opening cut in the rupturable member. According to the preferred embodiment of the invention the rupturable member includes a solid head seated in the end of the drain line having a rim extending peripherally therearound, the rim being clamped against the end of the drain line by a clamp ring having an interior shearing edge, the bottom of the rupturable member being convex and extending into the drain line. Means are provided to draw the rupturable member away from the drain line against the shearing edge to clear the drain line for outflow of sodium therethrough.

  9. Endovascular Treatment of Ruptured Abdominal Aortic Aneurysm with Aortocaval Fistula

    SciTech Connect

    Guzzardi, Giuseppe Fossaceca, Rita; Divenuto, Ignazio; Musiani, Antonello; Brustia, Piero; Carriero, Alessandro

    2010-08-15

    Aortocaval fistula (ACF) is a rare complication of abdominal aortic aneurysm (AAA). We report the endovascular repair of an AAA rupture into the inferior vena cava. A 78-year-old woman was admitted to our hospital for acute hypotension. She presented with a pulsatile abdominal mass and became rapidly anuric. Abdominal computed tomography (CT) showed an AAA rupture into the inferior vena cava. The features of the AAA made it suitable for endovascular repair. To prevent pulmonary embolism caused by the presence of sac thrombosis near the vena cava lumen, a temporary vena cava filter was deployed before the procedure. A bifurcated stent-graft was placed with the patient under local anaesthesia, and the AAA was successfully treated. A transient type II endoleak was detected on CT 3 days after endograft placement. At routine follow-up 6 and 12 months after the procedure, the patient was in good clinical condition, and the type II endoleak had sealed completely. Endovascular treatment offers an attractive therapeutic alternative to open repair in case of ACF; however, only small numbers of patients have been treated, and long-term follow-up interval is lacking.

  10. Incomplete Cesarean Scar Rupture

    PubMed Central

    Ahmadi, Firoozeh; Siahbazi, Shiva; Akhbari, Farnaz

    2013-01-01

    Background Uterine rupture at the site of a previous cesarean scar is an uncommon but catastrophic complication of pregnancy, which is associated with significant maternal and fetal morbidity and mortality. Case Presentation A 30-year old woman at 24th week of gestation and complaint of pain, contractions and spotting was admitted in Royan Institute in Tehran, Iran. She had a past medical history of an EP and a cesarean section delivery, respectively 4 and 2 years before hospitalization. Herniation of an amniotic membrane into the maternal bladder was found on ultrasound examination. Conclusion Risk factors of cesarean scar rupture should be considered in women undergoing subsequent pregnancies as they need extra care. Ultrasonography can be used to evaluate women with previous cesarean section to assess the risks of scar rupture during subsequent pregnancies. PMID:23926561

  11. Indications for and outcome of open AAA repair in the endovascular era.

    PubMed

    Wieker, Carola M; Spazier, Max; Böckler, Dittmar

    2016-04-01

    The benefits, safety and efficacy of endovascular aortic aneurysm repair (EVAR) is well documented and intensively reported in multiple randomized trials and meta-analysis. Therefore, EVAR became the first choice of abdominal aortic aneurysms (AAA) treatment in almost 70-100% of patients. Consecutively, open repair (OR) is performed less frequently in morphologically preselected patients. Anatomical condition remains the most important factor for indication for OR. Especially unfavorable intrarenal landing zone based on difficult neck anatomy like very short neck or excessive neck angulation is still the most predictive factor. Furthermore, patients presenting additional iliac aneurysms, aortoiliac occlusive disease or variations of renal arteries are recommended for OR. Randomized trials like EVAR 1, DREAM and OVER from the year 2004/2005 and 2009 showed lower 30-day mortality rates in EVAR compared to OR. However, the late mortality rates after two years became equal in both treatment options. Furthermore, reinterventions after EVAR occur more frequently than after OR. Analysis from our own data showed a higher 30-day mortality in the patients who underwent OR in the endovascular era (15% vs. 2.5%), however the number of emergency open AAA repair because of ruptured aneurysms was much higher in the endovascular era (32.5% vs. 5%). In conclusion, treatment of AAA has changed in the past decade. Nevertheless OR of AAA still remains as a safe and durable method in experienced surgeons, even in the endovascular era. High volume centres are needed to offer the best patients' treatment providing the best postoperative outcome. Therefore OR must remain a part of fellowship training in the future. To decide the best treatment option many facts like patients' fitness and preference or finally the anatomic suitability for endovascular repair have to be considered. PMID:26822580

  12. Risk Factors for Survival following Open Surgical Repair of Ruptured Abdominal Aortic Aneurysms: A 13-Year Experience

    PubMed Central

    Ozen, Anil; Hanedan, Muhammet Onur; Songur, Çetin Murat; Boysan, Emre; Unal, Ertekin Utku; Mola, Serkan; Erkengel, Halil Ibrahim; Kubat, Emre; Iscan, Zafer; Tutun, Ufuk; Sarıtas, Ahmet; Birincioglu, Cemal Levent

    2015-01-01

    Background: Surgical treatment of a ruptured abdominal aorta aneurysm (RAAA) continues to present a significant challenge to surgeons. There are some patient factors such as age and gender that cannot be changed, and comorbid conditions can be optimized but not eliminated. The purpose of this study was to identify the risk factors affecting high mortality after the surgical repair of an RAAA. Methods: Data on 121 patients who underwent surgical repair for RAAAs between January 1997 and June 2011 in our institution were collected retrospectively. All the patients had been diagnosed by computed tomography (CT) scans, and intraoperative extra-luminal blood was visualized intraoperatively. Variables studied comprised demographic data; preoperative, operative, and postoperative data; and the causes of mortality. Multivariate regression analysis was used to determine the predictors of mortality. Results: One hundred eight (89.2%) patients were male and 13 (10.7%) were female at an average age of 68.9 ± 10.5 years. Totally, 121 patients underwent surgery for RAAAs. Fifty-four patients had aortic tube grafts, 32 aortobiiliac grafts, 20 aortobifemoral grafts, 1 aortoiliac graft, and 1 aortofemoral graft for the replacement of the RAAAs. Seven patients had only surgical exploration. Operative mortality was 41.3% (50 patients). The factors associated with mortality were preoperative shock, free blood, positive inotropic agent, hematocrit value, and need for blood and plasma. In the multivariate analysis, preoperative shock and positive inotropic agents were found to be significant as the predictors of death (OR: 19.8, 95%CI: 3.2-122.8 and OR: 8.6, 95% CI: 2.9-26.3, respectively). Conclusion: This study revealed that the preoperative clinical findings affected the mortality associated with RAAAs. PMID:26697083

  13. 26 CFR 1.1368-2 - Accumulated adjustments account (AAA).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 11 2011-04-01 2011-04-01 false Accumulated adjustments account (AAA). 1.1368-2 Section 1.1368-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Small Business Corporations and Their Shareholders § 1.1368-2 Accumulated adjustments account (AAA)....

  14. Experimental validation of the Eclipse AAA algorithm.

    PubMed

    Breitman, Karen; Rathee, Satyapal; Newcomb, Chris; Murray, Brad; Robinson, Donald; Field, Colin; Warkentin, Heather; Connors, Sherry; Mackenzie, Marc; Dunscombe, Peter; Fallone, Gino

    2007-01-01

    The present study evaluates the performance of a newly released photon-beam dose calculation algorithm that is incorporated into an established treatment planning system (TPS). We compared the analytical anisotropic algorithm (AAA) factory-commissioned with "golden beam data" for Varian linear accelerators with measurements performed at two institutions using 6-MV and 15-MV beams. The TG-53 evaluation regions and criteria were used to evaluate profiles measured in a water phantom for a wide variety of clinically relevant beam geometries. The total scatter factor (TSF) for each of these geometries was also measured and compared against the results from the AAA. At one institute, TLD measurements were performed at several points in the neck and thoracic regions of a Rando phantom; at the other institution, ion chamber measurements were performed in a CIRS inhomogeneous phantom. The phantoms were both imaged using computed tomography (CT), and the dose was calculated using the AAA at corresponding detector locations. Evaluation of measured relative dose profiles revealed that 97%, 99%, 97%, and 100% of points at one institute and 96%, 88%, 89%, and 100% of points at the other institution passed TG-53 evaluation criteria in the outer beam, penumbra, inner beam, and buildup regions respectively. Poorer results in the inner beam regions at one institute are attributed to the mismatch of the measured profiles at shallow depths with the "golden beam data." For validation of monitor unit (MU) calculations, the mean difference between measured and calculated TSFs was less than 0.5%; test cases involving physical wedges had, in general, differences of more than 1%. The mean difference between point measurements performed in inhomogeneous phantoms and Eclipse was 2.1% (5.3% maximum) and all differences were within TG-53 guidelines of 7%. By intent, the methods and evaluation techniques were similar to those in a previous investigation involving another convolution

  15. AAAS Communicating Science Program: Reflections on Evaluation

    NASA Astrophysics Data System (ADS)

    Braha, J.

    2015-12-01

    The AAAS Center for Public Engagement (Center) with science builds capacity for scientists to engage public audiences by fostering collaboration among natural or physical scientists, communication researchers, and public engagement practitioners. The recently launched Leshner Leadership Institute empowers cohorts of mid-career scientists to lead public engagement by supporting their networks of scientists, researchers, and practitioners. The Center works closely with social scientists whose research addresses science communication and public engagement with science to ensure that the Communicating Science training program builds on empirical evidence to inform best practices. Researchers ( Besley, Dudo, & Storkdieck 2015) have helped Center staff and an external evaluator develop pan instrument that measures progress towards goals that are suggested by the researcher, including internal efficacy (increasing scientists' communication skills and confidence in their ability to engage with the public) and external efficacy (scientists' confidence in engagement methods). Evaluation results from one year of the Communicating Science program suggest that the model of training yields positive results that support scientists in the area that should lead to greater engagement. This talk will explore the model for training, which provides a context for strategic communication, as well as the practical factors, such as time, access to public engagement practitioners, and technical skill, that seems to contribute to increased willingness to engage with public audiences. The evaluation program results suggest willingness by training participants to engage directly or to take preliminary steps towards engagement. In the evaluation results, 38% of trained scientists reported time as a barrier to engagement; 35% reported concern that engagement would distract from their work as a barrier. AAAS works to improve practitioner-researcher-scientist networks to overcome such barriers.

  16. Protein quality control in organelles - AAA/FtsH story.

    PubMed

    Janska, Hanna; Kwasniak, Malgorzata; Szczepanowska, Joanna

    2013-02-01

    This review focuses on organellar AAA/FtsH proteases, whose proteolytic and chaperone-like activity is a crucial component of the protein quality control systems of mitochondrial and chloroplast membranes. We compare the AAA/FtsH proteases from yeast, mammals and plants. The nature of the complexes formed by AAA/FtsH proteases and the current view on their involvement in degradation of non-native organellar proteins or assembly of membrane complexes are discussed. Additional functions of AAA proteases not directly connected with protein quality control found in yeast and mammals but not yet in plants are also described shortly. Following an overview of the molecular functions of the AAA/FtsH proteases we discuss physiological consequences of their inactivation in yeast, mammals and plants. The molecular basis of phenotypes associated with inactivation of the AAA/FtsH proteases is not fully understood yet, with the notable exception of those observed in m-AAA protease-deficient yeast cells, which are caused by impaired maturation of mitochondrial ribosomal protein. Finally, examples of cytosolic events affecting protein quality control in mitochondria and chloroplasts are given. This article is part of a Special Issue entitled: Protein Import and Quality Control in Mitochondria and Plastids. PMID:22498346

  17. Morphological State as a Predictor for Reintervention and Mortality After EVAR for AAA

    SciTech Connect

    Ohrlander, Tomas; Dencker, Magnus; Acosta, Stefan

    2012-10-15

    Purpose: This study was designed to assess aorto-iliac morphological characteristics in relation to reintervention and all-cause long-term mortality in patients undergoing standard EVAR for infrarenal AAA. Methods: Patients treated with EVAR (Zenith{sup Registered-Sign} Stentgrafts, Cook) between May 1998 and February 2006 were prospectively enrolled in a computerized database where comorbidities and preoperative aneurysm morphology were entered. Reinterventions and mortality were checked until December 1, 2010. Median follow-up time was 68 months. Results: A total of 304 patients were included, of which 86% were men. Median age was 74 years. The reintervention rate was 23.4% (71/304). A greater diameter of the common iliac artery (p = 0.037; hazard ratio (HR) 1.037 [1.002-1.073]) was an independent factor for an increased number of reinterventions. The 30-day mortality rate was 3.0% (9/304). Aneurysm-related deaths due to AAA occurred in 4.9% (15/304). Five patients died due to a concomitant ruptured thoracic aortic aneurysm. The mortality until end of follow-up was 54.3% (165/304). The proportion of deaths caused by vascular diseases was 61.6%. The severity of angulation of the iliac arteries (p = 0.014; HR 1.018 [95% confidence interval (CI) 1.004-1.033]) and anemia (p = 0.044; HR 2.79 [95% CI 1.029-7.556]) remained as independent factors associated with all-cause long-term mortality. The crude reintervention-free survival rate at 1, 3, and 5 years was 84.5%, 64.8%, and 51.6%, respectively. Conclusions: The initial aorto-iliac morphological state in patients scheduled for standard EVAR for AAA seems to be strongly related to the need for reinterventions and long-term mortality.

  18. A Retrospective Analysis of Ruptured Breast Implants

    PubMed Central

    Baek, Woo Yeol; Lew, Dae Hyun

    2014-01-01

    Background Rupture is an important complication of breast implants. Before cohesive gel silicone implants, rupture rates of both saline and silicone breast implants were over 10%. Through an analysis of ruptured implants, we can determine the various factors related to ruptured implants. Methods We performed a retrospective review of 72 implants that were removed for implant rupture between 2005 and 2014 at a single institution. The following data were collected: type of implants (saline or silicone), duration of implantation, type of implant shell, degree of capsular contracture, associated symptoms, cause of rupture, diagnostic tools, and management. Results Forty-five Saline implants and 27 silicone implants were used. Rupture was diagnosed at a mean of 5.6 and 12 years after insertion of saline and silicone implants, respectively. There was no association between shell type and risk of rupture. Spontaneous was the most common reason for the rupture. Rupture management was implant change (39 case), microfat graft (2 case), removal only (14 case), and follow-up loss (17 case). Conclusions Saline implants have a shorter average duration of rupture, but diagnosis is easier and safer, leading to fewer complications. Previous-generation silicone implants required frequent follow-up observation, and it is recommended that they be changed to a cohesive gel implant before hidden rupture occurs. PMID:25396188

  19. Neuromuscular regulation in zebrafish by a large AAA+ ATPase/ubiquitin ligase, mysterin/RNF213

    PubMed Central

    Kotani, Yuri; Morito, Daisuke; Yamazaki, Satoru; Ogino, Kazutoyo; Kawakami, Koichi; Takashima, Seiji; Hirata, Hiromi; Nagata, Kazuhiro

    2015-01-01

    Mysterin (also known as RNF213) is a huge intracellular protein with two AAA+ ATPase modules and a RING finger ubiquitin ligase domain. Mysterin was originally isolated as a significant risk factor for the cryptogenic cerebrovascular disorder moyamoya disease, and was found to be involved in physiological angiogenesis in zebrafish. However, the function and the physiological significance of mysterin in other than blood vessels remain largely unknown, although mysterin is ubiquitously expressed in animal tissues. In this study, we performed antisense-mediated suppression of a mysterin orthologue in zebrafish larvae and revealed that mysterin-deficient larvae showed significant reduction in fast myofibrils and immature projection of primary motoneurons, leading to severe motor deficits. Fast muscle-specific restoration of mysterin expression cancelled these phenotypes, and interestingly both AAA+ ATPase and ubiquitin ligase activities of mysterin were indispensable for proper fast muscle formation, demonstrating an essential role of mysterin and its enzymatic activities in the neuromuscular regulation in zebrafish. PMID:26530008

  20. Autocatalytic processing of m-AAA protease subunits in mitochondria.

    PubMed

    Koppen, Mirko; Bonn, Florian; Ehses, Sarah; Langer, Thomas

    2009-10-01

    m-AAA proteases are ATP-dependent proteolytic machines in the inner membrane of mitochondria which are crucial for the maintenance of mitochondrial activities. Conserved nuclear-encoded subunits, termed paraplegin, Afg3l1, and Afg3l2, form various isoenzymes differing in their subunit composition in mammalian mitochondria. Mutations in different m-AAA protease subunits are associated with distinct neuronal disorders in human. However, the biogenesis of m-AAA protease complexes or of individual subunits is only poorly understood. Here, we have examined the processing of nuclear-encoded m-AAA protease subunits upon import into mitochondria and demonstrate autocatalytic processing of Afg3l1 and Afg3l2. The mitochondrial processing peptidase MPP generates an intermediate form of Afg3l2 that is matured autocatalytically. Afg3l1 or Afg3l2 are also required for maturation of newly imported paraplegin subunits after their cleavage by MPP. Our results establish that mammalian m-AAA proteases can act as processing enzymes in vivo and reveal overlapping activities of Afg3l1 and Afg3l2. These findings might be of relevance for the pathogenesis of neurodegenerative disorders associated with mutations in different m-AAA protease subunits. PMID:19656850

  1. Poly implant breast implants (PIP) and the rupture risk in asymptomatic patients: a warning for greater clinician suspicion in assessment and counselling.

    PubMed

    Mylvaganam, Senthurun; Taylor, Rebecca; Thrush, Steven

    2013-01-01

    Poly implant prostheses (PIP) implants have raised concern due to the increased reporting of ruptures prompting a UK review in 2012 recommending that symptomatic patients only undergo magnetic resonance imaging (MRI) and explantation as necessary. Literature suggests two of three implant ruptures are asymptomatic. In this case, a 45-year-old woman with bilateral breast implants for cosmesis presented due to publicity of PIP implants. She was asymptomatic with no clinical signs suggestive of rupture. Due to patient intention for explanation of rupture, an MRI scan was undertaken which showed extensive silicone between the chest wall and lung bilaterally. The lung multidisciplinary team did not recommend removal of the lung silicone infiltrate. The implants were removed confirming rupture. Symptoms and signs cannot be relied upon to diagnose implant ruptures. Where patient concern exists with expressed intent for explantation if proven rupture, MRI assessment is a reliable tool where clinical uncertainty over rupture is present. PMID:24964409

  2. Poly implant breast implants (PIP) and the rupture risk in asymptomatic patients: a warning for greater clinician suspicion in assessment and counselling

    PubMed Central

    Mylvaganam, Senthurun; Taylor, Rebecca; Thrush, Steven

    2013-01-01

    Poly implant prostheses (PIP) implants have raised concern due to the increased reporting of ruptures prompting a UK review in 2012 recommending that symptomatic patients only undergo magnetic resonance imaging (MRI) and explantation as necessary. Literature suggests two of three implant ruptures are asymptomatic. In this case, a 45-year-old woman with bilateral breast implants for cosmesis presented due to publicity of PIP implants. She was asymptomatic with no clinical signs suggestive of rupture. Due to patient intention for explanation of rupture, an MRI scan was undertaken which showed extensive silicone between the chest wall and lung bilaterally. The lung multidisciplinary team did not recommend removal of the lung silicone infiltrate. The implants were removed confirming rupture. Symptoms and signs cannot be relied upon to diagnose implant ruptures. Where patient concern exists with expressed intent for explantation if proven rupture, MRI assessment is a reliable tool where clinical uncertainty over rupture is present. PMID:24964409

  3. Inhibitors of the AAA+ Chaperone p97

    PubMed Central

    Chapman, Eli; Maksim, Nick; de la Cruz, Fabian; La Clair, James J.

    2015-01-01

    It is remarkable that a pathway as ubiquitous as protein quality control can be targeted to treat cancer. Bortezomib, an inhibitor of the proteasome, was first approved by the US Food and Drug Administration (FDA) more than 10 years ago to treat refractory myeloma and later extended to lymphoma. Its use has increased the survival rate of myeloma patients by as much as three years. This success was followed with the recent accelerated approval of the natural product derived proteasome inhibitor carfilzomib (Kyprolis®), which is used to treat patients with bortezomib-resistant multiple myeloma. The success of these two drugs has validated protein quality control as a viable target to fight select cancers, but begs the question why are proteasome inhibitors limited to lymphoma and myeloma? More recently, these limitations have encouraged the search for additional targets within the protein quality control system that might offer heightened cancer cell specificity, enhanced clinical utility, a lower rate of resistance, reduced toxicity, and mitigated side effects. One promising target is p97, an ATPase associated with various cellular activities (AAA+) chaperone. p97 figures prominently in protein quality control as well as serving a variety of other cellular functions associated with cancer. More than a decade ago, it was determined that up-regulation of p97 in many forms of cancer correlates with a poor clinical outcome. Since these initial discoveries, a mechanistic explanation for this observation has been partially illuminated, but details are lacking. Understandably, given this clinical correlation, myriad roles within the cell, and its importance in protein quality control, p97 has emerged as a potential therapeutic target. This review provides an overview of efforts towards the discovery of small molecule inhibitors of p97, offering a synopsis of efforts that parallel the excellent reviews that currently exist on p97 structure, function, and physiology. PMID

  4. Ruptured thought: rupture as a critical attitude to nursing research.

    PubMed

    Beedholm, Kirsten; Lomborg, Kirsten; Frederiksen, Kirsten

    2014-04-01

    In this paper, we introduce the notion of ‘rupture’ from the French philosopher Michel Foucault, whose studies of discourse and governmentality have become prominent within nursing research during the last 25 years. We argue that a rupture perspective can be helpful for identifying and maintaining a critical potential within nursing research. The paper begins by introducing rupture as an inheritance from the French epistemological tradition. It then describes how rupture appears in Foucault's works, as both an overall philosophical approach and as an analytic tool in his historical studies. Two examples of analytical applications of rupture are elaborated. In the first example, rupture has inspired us to make an effort to seek alternatives to mainstream conceptions of the phenomenon under study. In the second example, inspired by Foucault's work on discontinuity, we construct a framework for historical epochs in nursing history. The paper concludes by discussing the potential of the notion of rupture as a response to the methodological concerns regarding the use of Foucault-inspired discourse analysis within nursing research. We agree with the critique of Cheek that the critical potential of discourse analysis is at risk of being undermined by research that tends to convert the approach into a fixed method. PMID:24741691

  5. Plasma cytokine levels and risks of abdominal aortic aneurysms: A population-based prospective cohort study

    PubMed Central

    Liao, Mengyang; Liu, Cong-Lin; Lv, Bing-Jie; Zhang, Jin-Ying; Cheng, Longxian; Cheng, Xiang; Lindholt, Jes S.; Rasmussen, Lars M.; Shi, Guo-Ping

    2015-01-01

    Background Abdominal aortic aneurysm (AAA) is characterized by inflammatory cell accumulation in AAA lesions that produce inflammatory cytokines and advance its pathogenesis. Peripheral cytokines may predict the degree or risk of AAA. Methods and Results ELISA determined plasma interleukin-6 (IL6), IL10, IL17A, IFN-γ, and C-reactive protein (CRP) from 476 AAA patients and 200 controls. AAA patients had lower IL6, IFN-γ, IL10, IL17A, and higher CRP than controls. IL10 correlated positively with IFN-γ, IL17A, or IL6, but not CRP in control or AAA populations. IL10 associated negatively with systolic blood pressure, whereas CRP associated positively with diastolic blood pressure and body mass index. CRP was an independent AAA risk factor and correlated positively with aortic diameters before and after adjustments for other risk factors. IFN-γ, IL17A, and CRP correlated positively with cross-sectional AAA area after adjustment. IL10 correlated positively with AAA growth rate before and after adjustment. AAA patients with CRP levels above the median doubled the risk of death. Conclusions Reduced IFN-γ, IL10, and IL17A in AAA patients, positive correlations of IFN-γ and IL17A with cross-sectional AAA area, IL10 with AAA growth rate, and IL10 with IFN-γ and IL17A suggest combined Th1, Th2, and Th17 immune responses in human AAAs. PMID:25856542

  6. Chronic Contained Rupture of an Abdominal Aortic Aneurysm: From Diagnosis to Endovascular Resolution

    SciTech Connect

    Gandini, Roberto Chiocchi, Marcello; Maresca, Luciano; Pipitone, Vincenzo; Messina, Massimo; Simonetti, Giovanni

    2008-07-15

    A male patient, 69 years old, presented with fever, leucocytosis, and persistent low back pain; he also had an abdominal aortic aneurysm (AAA), as previously diagnosed by Doppler UltraSound (US), and was admitted to our hospital. On multislice computed tomography (msCT), a large abdominal mass having no definite border and involving the aorta and both of the psoas muscles was seen. This mass involved the forth-lumbar vertebra with lysis, thus simulating AAA rupture into a paraspinal collection; it was initially considered a paraspinal abscess. After magnetic resonance imaging examination and culture of the fluid aspirated from the mass, no infective organisms were found; therefore, a diagnosisof chronically contained AAA rupture was made, and an aortic endoprosthesis was subsequently implanted. The patient was discharged with decreased lumbar pain. At 12-month follow-up, no evidence of leakage was observed. To our knowledge, this is the first case of endoprosthesis implantation in a patient, who was a poor candidate for surgical intervention due to renal failure, leucocytosis and high fever, having a chronically contained AAA ruptured simulatingspodilodiscitis abscess. Appropriate diagnosis and therapy resolved potentially crippling pathology and avoided surgical graft-related complications.

  7. Tendon Ruptures Associated With Corticosteroid Therapy

    PubMed Central

    Halpern, Alan A.; Horowitz, Bruce G.; Nagel, Donald A.

    1977-01-01

    In five patients, tendon ruptures occurred in association with corticosteroid therapy, either systemic or local infiltration. The chronic nature of the pain in all of these patients suggests that what we often call tendinitis may in fact be early or partial ruptures of tendons. Patients who receive local infiltration of corticosteroids should perhaps be advised of the risk of a ruptured tendon. In addition, particularly when the Achilles tendon is involved, immobilization should be utilized initially for a presumed tendinitis or early rupture, to protect the tendon from further injury. ImagesFigure 1.Figure 2. PMID:919538

  8. Spontaneous rupture of uterine leiomyoma during labour

    PubMed Central

    Ramskill, Nikki; Hameed, Aisha; Beebeejaun, Yusuf

    2014-01-01

    Uterine rupture in labour requires an emergency caesarean section. In women with a uterine scar, either from gynaecological surgery or from a previous caesarean section, it is well documented that the risk of rupture is higher than in those without. Spontaneous uterine rupture in a uterus with fibroids during pregnancy or labour is extremely rare. We present a case of a 33-year-old, unbooked pregnant woman from Nigeria who had a uterine rupture secondary to fibroids. She required an emergency caesarean section in labour. The fibroids were not removed. Her baby was born alive and in good condition and she made an uneventful recovery. PMID:25199188

  9. Role of AAA(+)-proteins in peroxisome biogenesis and function.

    PubMed

    Grimm, Immanuel; Erdmann, Ralf; Girzalsky, Wolfgang

    2016-05-01

    Mutations in the PEX1 gene, which encodes a protein required for peroxisome biogenesis, are the most common cause of the Zellweger spectrum diseases. The recognition that Pex1p shares a conserved ATP-binding domain with p97 and NSF led to the discovery of the extended family of AAA+-type ATPases. So far, four AAA+-type ATPases are related to peroxisome function. Pex6p functions together with Pex1p in peroxisome biogenesis, ATAD1/Msp1p plays a role in membrane protein targeting and a member of the Lon-family of proteases is associated with peroxisomal quality control. This review summarizes the current knowledge on the AAA+-proteins involved in peroxisome biogenesis and function. PMID:26453804

  10. Risk Factors and Epidemiology of Coccidioidomycosis Demonstrated by a Case of Spontaneous Pulmonary Rupture of Cavitary Coccidioidomycosis.

    PubMed

    Yau, Amy A

    2016-01-01

    A 31-year-old Hispanic male with no medical history was admitted for fevers, pleurisy, and cough after recent oral surgery and completing demolition and construction work in Juarez, Mexico. Imaging showed a 4.4 cm cavitary lesion and bilateral tree-in-bud opacities. Initial suspicion of bacterial infection confirmed with clinical improvement on culture specific antibiotics, but after discharge he returned with progression of symptoms and new dyspnea. Radiograph showed a pyopneumothorax. Chest computed tomography after thoracostomy showed worsening infiltrates and another cavitary lesion. Symptoms persisted despite addition of broad spectrum antibiotics. Surgical repair for persistent air leak was required. Weeks after discharge, cultures and serologies returned positive for Coccidioidomycosis immitis. Coccidioides species cause up to 30% of community-acquired pneumonia and incidental cavitary lesions in endemic regions. Symptoms are nonspecific yet usually involve fatigue, cough, and pleurisy. Most hosts have spontaneous resolution; however, certain demographics such as Hispanics and diabetics, later diagnosed in our patient, have higher morbidity. As seen with our patient, cavitary rupture and bronchopleural fistulas are rare occurring in 2.6% of cavitary lesions. High suspicion based on symptoms and host demographics is important to assist in early diagnosis and treatment to avoid and treat this common pathogen's presentations. PMID:26904326

  11. Risk Factors and Epidemiology of Coccidioidomycosis Demonstrated by a Case of Spontaneous Pulmonary Rupture of Cavitary Coccidioidomycosis

    PubMed Central

    Yau, Amy A.

    2016-01-01

    A 31-year-old Hispanic male with no medical history was admitted for fevers, pleurisy, and cough after recent oral surgery and completing demolition and construction work in Juarez, Mexico. Imaging showed a 4.4 cm cavitary lesion and bilateral tree-in-bud opacities. Initial suspicion of bacterial infection confirmed with clinical improvement on culture specific antibiotics, but after discharge he returned with progression of symptoms and new dyspnea. Radiograph showed a pyopneumothorax. Chest computed tomography after thoracostomy showed worsening infiltrates and another cavitary lesion. Symptoms persisted despite addition of broad spectrum antibiotics. Surgical repair for persistent air leak was required. Weeks after discharge, cultures and serologies returned positive for Coccidioidomycosis immitis. Coccidioides species cause up to 30% of community-acquired pneumonia and incidental cavitary lesions in endemic regions. Symptoms are nonspecific yet usually involve fatigue, cough, and pleurisy. Most hosts have spontaneous resolution; however, certain demographics such as Hispanics and diabetics, later diagnosed in our patient, have higher morbidity. As seen with our patient, cavitary rupture and bronchopleural fistulas are rare occurring in 2.6% of cavitary lesions. High suspicion based on symptoms and host demographics is important to assist in early diagnosis and treatment to avoid and treat this common pathogen's presentations. PMID:26904326

  12. Meiotic Clade AAA ATPases: Protein Polymer Disassembly Machines.

    PubMed

    Monroe, Nicole; Hill, Christopher P

    2016-05-01

    Meiotic clade AAA ATPases (ATPases associated with diverse cellular activities), which were initially grouped on the basis of phylogenetic classification of their AAA ATPase cassette, include four relatively well characterized family members, Vps4, spastin, katanin and fidgetin. These enzymes all function to disassemble specific polymeric protein structures, with Vps4 disassembling the ESCRT-III polymers that are central to the many membrane-remodeling activities of the ESCRT (endosomal sorting complexes required for transport) pathway and spastin, katanin p60 and fidgetin affecting multiple aspects of cellular dynamics by severing microtubules. They share a common domain architecture that features an N-terminal MIT (microtubule interacting and trafficking) domain followed by a single AAA ATPase cassette. Meiotic clade AAA ATPases function as hexamers that can cycle between the active assembly and inactive monomers/dimers in a regulated process, and they appear to disassemble their polymeric substrates by translocating subunits through the central pore of their hexameric ring. Recent studies with Vps4 have shown that nucleotide-induced asymmetry is a requirement for substrate binding to the pore loops and that recruitment to the protein lattice via MIT domains also relieves autoinhibition and primes the AAA ATPase cassettes for substrate binding. The most striking, unifying feature of meiotic clade AAA ATPases may be their MIT domain, which is a module that is found in a wide variety of proteins that localize to ESCRT-III polymers. Spastin also displays an adjacent microtubule binding sequence, and the presence of both ESCRT-III and microtubule binding elements may underlie the recent findings that the ESCRT-III disassembly function of Vps4 and the microtubule-severing function of spastin, as well as potentially katanin and fidgetin, are highly coordinated. PMID:26555750

  13. Endovascular vs open repair for ruptured abdominal aortic aneurysm

    PubMed Central

    Nedeau, April E.; Pomposelli, Frank B.; Hamdan, Allen D.; Wyers, Mark C.; Hsu, Richard; Sachs, Teviah; Siracuse, Jeffrey J.; Schermerhorn, Mark L.

    2014-01-01

    Objective Endovascular repair (EVAR) of ruptured abdominal aortic aneurysm (rAAA) has become first-line therapy at our institution and is performed under a standardized protocol. We compare perioperative mortality, midterm survival, and morbidity after EVAR and open surgical repair (OSR). Methods Records were retrospectively reviewed from May 2000 to September 2010 for repair of infrarenal rAAAs. Primary end points included perioperative mortality and midterm survival. Secondary end points included acute limb ischemia, length of stay, ventilator-dependent respiratory failure, myocardial infarction, renal failure, abdominal compartment syndrome, and secondary intervention. Statistical analysis was performed using the t-test,X2 test, the Fisher exact test, and logistic regression calculations. Midterm survival was assessed with Kaplan-Meier analysis and Cox proportional hazard models. Results Seventy-four infrarenal rAAAs were repaired, 19 by EVAR and 55 by OSR. Despite increased age and comorbidity in the EVAR patients, perioperative mortality was 15.7% for EVAR, which was significantly lower than the 49% for OSR (odds ratio, 0.19; 95% CI, 0.05-0.74; P = .008). Midterm survival also favored EVAR (hazard ratio, 0.40; 95% CI, 0.21-0.77; P = .028, adjusted for age and sex). Mean follow-up was 20 months, and 1-year survival was 60% for EVAR vs 45% for OSR. Mean length of stay for patients surviving >1 day was 10 days for EVAR and 21 days for OSR (P = .004). Ventilator-dependent respiratory failure was 5% in the EVAR group vs 42% for OSR (odds ratio, 0.08; 95% CI, 0.01-0.62; P = .001). Conclusions EVAR of rAAA has a superior perioperative survival advantage and decreased morbidity vs OSR. Although not statistically significant, overall survival favors EVAR. We recommend that EVAR be considered as the first-line treatment of rAAAs and practiced as the standard of care. PMID:22626871

  14. Protein unfolding and degradation by the AAA+ Lon protease.

    PubMed

    Gur, Eyal; Vishkautzan, Marina; Sauer, Robert T

    2012-02-01

    AAA+ proteases employ a hexameric ring that harnesses the energy of ATP binding and hydrolysis to unfold native substrates and translocate the unfolded polypeptide into an interior compartment for degradation. What determines the ability of different AAA+ enzymes to unfold and thus degrade different native protein substrates is currently uncertain. Here, we explore the ability of the E. coli Lon protease to unfold and degrade model protein substrates beginning at N-terminal, C-terminal, or internal degrons. Lon has historically been viewed as a weak unfoldase, but we demonstrate robust and processive unfolding/degradation of some substrates with very stable protein domains, including mDHFR and titin(I27) . For some native substrates, Lon is a more active unfoldase than related AAA+ proteases, including ClpXP and ClpAP. For other substrates, this relationship is reversed. Thus, unfolding activity does not appear to be an intrinsic enzymatic property. Instead, it depends on the specific protease and substrate, suggesting that evolution has diversified rather than optimized the protein unfolding activities of different AAA+ proteases. PMID:22162032

  15. Ex-congressman Rush Holt to lead AAAS

    NASA Astrophysics Data System (ADS)

    Banks, Michael

    2015-01-01

    The particle physicist Rush Holt, who served in the US Congress for 15 years, has been named as the next chief executive of the American Association for the Advancement of Science (AAAS) - the non-profit US society that promotes public engagement with science and technology.

  16. The Adult Asperger Assessment (AAA): A Diagnostic Method

    ERIC Educational Resources Information Center

    Baron-Cohen, Simon; Wheelwright, Sally; Robinson, Janine; Woodbury-Smith, Marc

    2005-01-01

    At the present time there are a large number of adults who have "suspected" Asperger syndrome (AS). In this paper we describe a new instrument, the Adult Asperger Assessment (AAA), developed in our clinic for adults with AS. The need for a new instrument relevant to the diagnosis of AS in adulthood arises because existing instruments are designed…

  17. Premature rupture of membranes

    MedlinePlus

    ... When the water breaks early, it is called premature rupture of membranes (PROM). Most women will go ... th week of pregnancy, it is called preterm premature rupture of membranes (PPROM). The earlier your water ...

  18. Inhibition of early AAA formation by aortic intraluminal pentagalloyl glucose (PGG) infusion in a novel porcine AAA model

    PubMed Central

    Kloster, Brian O.; Lund, Lars; Lindholt, Jes S.

    2016-01-01

    Background The vast majority of abdominal aortic aneurysms found in screening programs are small, and as no effective treatment exits, many will expand until surgery is indicated. Therefore, it remains intriguing to develop a safe and low cost treatment of these small aneurysms, that is able to prevent or delay their expansion. In this study, we investigated whether intraluminal delivered pentagalloyl glucose (PGG) can impair the early AAA development in a porcine model. Methods The infrarenal aorta was exposed in thirty pigs. Twenty underwent an elastase based AAA inducing procedure and ten of these received an additional intraluminal PGG infusion. The final 10 were sham operated and served as controls. Results All pigs who only had an elastase infusion developed macroscopically expanding AAAs. In pigs treated with an additional PGG infusion the growth rate of the AP-diameter rapidly returned to physiological values as seen in the control group. In the elastase group, histology revealed more or less complete resolution of the elastic lamellae in the media while they were more abundant, coherent and structurally organized in the PGG group. The control group displayed normal physiological growth and histology. Conclusion In our model, intraluminal delivered PGG is able to penetrate the aortic wall from the inside and impair the early AAA development by stabilizing the elastic lamellae and preserving their integrity. The principle holds a high clinical potential if it can be translated to human conditions, since it, if so, potentially could represent a new drug for stabilizing small abdominal aneurysms. PMID:27144001

  19. Glass rupture disk

    DOEpatents

    Glass, S. Jill; Nicolaysen, Scott D.; Beauchamp, Edwin K.

    2002-01-01

    A frangible rupture disk and mounting apparatus for use in blocking fluid flow, generally in a fluid conducting conduit such as a well casing, a well tubing string or other conduits within subterranean boreholes. The disk can also be utilized in above-surface pipes or tanks where temporary and controllable fluid blockage is required. The frangible rupture disk is made from a pre-stressed glass with controllable rupture properties wherein the strength distribution has a standard deviation less than approximately 5% from the mean strength. The frangible rupture disk has controllable operating pressures and rupture pressures.

  20. Early and delayed rupture after endovascular abdominal aortic aneurysm repair in a 10-year multicenter registry

    PubMed Central

    Candell, Leah; Tucker, Lue-Yen; Goodney, Philip; Walker, Joy; Okuhn, Steven; Hill, Bradley; Chang, Robert

    2014-01-01

    Objective Rupture after abdominal endovascular aortic aneurysm repair (EVAR) is a function of graft maintenance of the seal and fixation. We describe our 10-year experience with rupture after EVAR. Methods From 2000 to 2010, 1736 patients with abdominal aortic aneurysm (AAA) from 17 medical centers underwent EVAR in a large, regional integrated health care system. Preoperative demographic and clinical data of interest were collected and stored in our registry. We retrospectively identified patients with postoperative rupture, characterized as “early” and “delayed” rupture (≤30 days and >30 days after the initial EVAR, respectively), and identified predictors associated with delayed rupture. Results The overall follow-up rate was 92%, and the median follow-up was 2.7 years (interquartile range, 1.2–4.4 years) in these 1736 EVAR patients. We identified 20 patients with ruptures; 70% were male, the mean age was 79 years, and mean AAA size at the initial EVAR was 6.3 cm. Six patients underwent initial EVAR for rupture (n = 2) or symptomatic presentation (n = 4). Of the 20 post-EVAR ruptures, 25% (five of 20) were early, all occurring within 2 days after the initial EVAR. Of these five patients, four had intraoperative adverse events leading directly to rupture, with one type I and one type III endoleak. Of the five early ruptures, four patients underwent endovascular repair and one received repair with open surgery, resulting in two perioperative deaths. Among the remaining 15 patients, the median time from initial EVAR to rupture was 31.1 months (interquartile range, 13.8–57.3 months). Most of these delayed ruptures (10 of 15) were preceded by AAA sac increases, including three patients with known endoleaks who underwent reintervention. At the time of delayed rupture, nine of 15 patients had new endoleaks. Among all 20 patients, six patients did not undergo repair (all delayed patients) and died, nine underwent repeated EVAR, and five had open repair

  1. A structural analysis of the AAA+ domains in Saccharomyces cerevisiae cytoplasmic dynein.

    PubMed

    Gleave, Emma S; Schmidt, Helgo; Carter, Andrew P

    2014-06-01

    Dyneins are large protein complexes that act as microtubule based molecular motors. The dynein heavy chain contains a motor domain which is a member of the AAA+ protein family (ATPases Associated with diverse cellular Activities). Proteins of the AAA+ family show a diverse range of functionalities, but share a related core AAA+ domain, which often assembles into hexameric rings. Dynein is unusual because it has all six AAA+ domains linked together, in one long polypeptide. The dynein motor domain generates movement by coupling ATP driven conformational changes in the AAA+ ring to the swing of a motile element called the linker. Dynein binds to its microtubule track via a long antiparallel coiled-coil stalk that emanates from the AAA+ ring. Recently the first high resolution structures of the dynein motor domain were published. Here we provide a detailed structural analysis of the six AAA+ domains using our Saccharomycescerevisiae crystal structure. We describe how structural similarities in the dynein AAA+ domains suggest they share a common evolutionary origin. We analyse how the different AAA+ domains have diverged from each other. We discuss how this is related to the function of dynein as a motor protein and how the AAA+ domains of dynein compare to those of other AAA+ proteins. PMID:24680784

  2. Mitochondrial AAA proteases--towards a molecular understanding of membrane-bound proteolytic machines.

    PubMed

    Gerdes, Florian; Tatsuta, Takashi; Langer, Thomas

    2012-01-01

    Mitochondrial AAA proteases play an important role in the maintenance of mitochondrial proteostasis. They regulate and promote biogenesis of mitochondrial proteins by acting as processing enzymes and ensuring the selective turnover of misfolded proteins. Impairment of AAA proteases causes pleiotropic defects in various organisms including neurodegeneration in humans. AAA proteases comprise ring-like hexameric complexes in the mitochondrial inner membrane and are functionally conserved from yeast to man, but variations are evident in the subunit composition of orthologous enzymes. Recent structural and biochemical studies revealed how AAA proteases degrade their substrates in an ATP dependent manner. Intersubunit coordination of the ATP hydrolysis leads to an ordered ATP hydrolysis within the AAA ring, which ensures efficient substrate dislocation from the membrane and translocation to the proteolytic chamber. In this review, we summarize recent findings on the molecular mechanisms underlying the versatile functions of mitochondrial AAA proteases and their relevance to those of the other AAA+ machines. PMID:22001671

  3. Second-Trimester Uterine Rupture: Lessons Learnt

    PubMed Central

    F. ABDULWAHAB, Dalia; ISMAIL, Hamizah; NUSEE, Zalina

    2014-01-01

    Uterine rupture is a rare life-threatening complication. It mainly occurs in the third trimester of pregnancy and is rarely seen during the first or second trimesters. Our centre experienced three important cases of uterine rupture. First case: spontaneous uterine rupture at 14 weeks of pregnancy, which was diagnosed at autopsy. It was misled by the ultrasound finding of an intrauterine pregnancy, and searching for other non-gynaecological causes delayed the urgent obstetric surgical management. Second case: ruptured uterus at 24 weeks following medical termination due to foetal anomaly. It was diagnosed only at laparotomy indicated for failed medical termination and chorioamnionitis. Third case: uterine rupture at 21 weeks of pregnancy in a patient with gastroenterology symptoms. In these reports, we have discussed the various risk factors, presentations, course of events and difficulties in diagnosing uterine rupture. The study concludes that the clinical presentation of uterine ruptures varies. It occurs regardless of gestational age. Ultrasound findings of intrauterine pregnancy with free fluid do not exclude uterine rupture or ectopic pregnancy. Searching for non-gynaecological causes in such clinical presentations might delay crucial surgical intervention, which leads to unnecessary morbidity, mortality or loss of obstetrics function. PMID:25977625

  4. Polypeptide translocation by the AAA+ ClpXP protease machine

    PubMed Central

    Barkow, Sarah R.; Levchenko, Igor; Baker, Tania A.; Sauer, Robert T.

    2009-01-01

    In the AAA+ ClpXP protease, ClpX uses repeated cycles of ATP hydrolysis to pull native proteins apart and to translocate the denatured polypeptide into ClpP for degradation. Here, we probe polypeptide features important for translocation. ClpXP degrades diverse synthetic peptide substrates despite major differences in side-chain chirality, size, and polarity. Moreover, translocation occurs without a peptide –NH and with 10 methylenes between successive peptide bonds. Pulling on homopolymeric tracts of glycine, proline, and lysine also allows efficient ClpXP degradation of a stably folded protein. Thus, minimal chemical features of a polypeptide chain are sufficient for translocation and protein unfolding by the ClpX machine. These results suggest that the translocation pore of ClpX is highly elastic, allowing interactions with a wide-range of chemical groups, a feature likely to be shared by many AAA+ unfoldases. PMID:19549599

  5. Self-Rupturing Hermetic Valve

    NASA Technical Reports Server (NTRS)

    Tucker, Curtis E., Jr.; Sherrit, Stewart

    2011-01-01

    For commercial, military, and aerospace applications, low-cost, small, reliable, and lightweight gas and liquid hermetically sealed valves with post initiation on/off capability are highly desirable for pressurized systems. Applications include remote fire suppression, single-use system-pressurization systems, spacecraft propellant systems, and in situ instruments. Current pyrotechnic- activated rupture disk hermetic valves were designed for physically larger systems and are heavy and integrate poorly with portable equipment, aircraft, and small spacecraft and instrument systems. Additionally, current pyrotechnically activated systems impart high g-force shock loads to surrounding components and structures, which increase the risk of damage and can require additional mitigation. The disclosed mechanism addresses the need for producing a hermetically sealed micro-isolation valve for low and high pressure for commercial, aerospace, and spacecraft applications. High-precision electrical discharge machining (EDM) parts allow for the machining of mated parts with gaps less than a thousandth of an inch. These high-precision parts are used to support against pressure and extrusion, a thin hermetically welded diaphragm. This diaphragm ruptures from a pressure differential when the support is removed and/or when the plunger is forced against the diaphragm. With the addition of conventional seals to the plunger and a two-way actuator, a derivative of this design would allow nonhermetic use as an on/off or metering valve after the initial rupturing of the hermetic sealing disk. In addition, in a single-use hermetically sealed isolation valve, the valve can be activated without the use of potential leak-inducing valve body penetrations. One implementation of this technology is a high-pressure, high-flow-rate rupture valve that is self-rupturing, which is advantageous for high-pressure applications such as gas isolation valves. Once initiated, this technology is self

  6. Rupture, resilience, and risk: relationships between mental health and migration among gay-identified men in North America.

    PubMed

    Lewis, Nathaniel M

    2014-05-01

    An established body of research in psychology, psychiatry and epidemiology links social stigma and stress with poor mental and sexual health outcomes among gay-identified men. Less work considers how these linkages are mediated by place and almost none considers the role of movement across places. This qualitative study, based on the migration narratives of 48 gay-identified men living in Ottawa, Ontario, Canada, and Washington, D.C., U.S.A. gives more careful consideration to the ways in which mental and emotional health issues (e.g., anxiety, depression, substance use) in this population both precipitate migration and stem from migration. The narratives show that decisions to migrate often emerge from men׳s experiences of place-based minority stress and associated health outcomes. At the same time, moving to urban gay communities, when coupled with other life circumstances, can create or reinforce physical and emotional insecurities that lead to low self-esteem, substance use and sexual risk-taking. PMID:24662530

  7. Distribution and length of osteophytes in the lumbar vertebrae and risk of rupture of abdominal aortic aneurysms: a study of dry bones from Chiang Mai, Thailand.

    PubMed

    Chanapa, Patcharin; Yoshiyuki, Tohno; Mahakkanukrauh, Pasuk

    2014-09-01

    Vertebral osteophytes are a characteristic feature of intervertebral disc degeneration. In the lumbar spinal region, the two major structures in close proximity anterior to the spine are the inferior vena cava and the abdominal aorta, both of which have been reported to be affected by osteophytes. The purpose of this study was to determine the distribution, classification and lengths of osteophytes in the lumbar vertebrae. One hundred and eighty lumbar columns of 90 males and 90 females from Chiang Mai, Thailand, in the age range 15 to 96 years (mean age, 63 years) were collected. The measuring length of osteophytes was assessed on vertebral body and articular facet. Statistical analysis was performed by descriptive analysis, chi-square and Pearson Correlation. Lumbar osteophytes were presented in 175 specimens (97.2%), 88 males and 87 females. The highest frequency was at L4, most were on the superior, inferior surface of body and articular facet (39.7%, 38.4%, and 22%), respectively. The greatest mean length was 3.47±2.21 mm at L5, and the longest length of anterior superior surface of body was 28.56 mm. The osteophyte length was significantly correlated directly with age (P<0.01), and males were significantly greater than females (P<0.05). The highest prevalence of osteophytes was on the anterior side of superior surface of body (30.4%), and the classification was traction. It can be proposed that the abdominal aorta could be damaged, especially a risk of rupture of abdominal aortic aneurysm. PMID:25276474

  8. Risk Factor Analysis for the Immunogenicity of Adalimumab Associated with Decreased Clinical Response in Chinese Patients with Psoriasis.

    PubMed

    Chiu, Hsien-Yi; Wang, Ting-Shun; Chan, Chih-Chieh; Lin, Sung-Jan; Tsai, Tsen-Fang

    2015-07-01

    Although anti-drug antibodies against biologics have been associated with decreased clinical efficacy, the immunogenicity of biologics seems to vary between drugs, diseases and ethnicities. This study aims to investigate the predictors for the formation of anti-adalimumab antibodies (AAA) and the clinical consequences of AAA formation. In 53 Chinese psoriatic patients treated with adalimumab, AAA was detected in 50.9%. Differences in Psoriasis Area and Severity Index 75 (PASI75) response rates among patients with and without AAA were significant (44.4% vs. 88.5%; p = 0.001). Patients with AAA had significantly lower trough concentrations of adalimumab than those without AAA. Risk factor analysis showed that treatment interruption, low trough adalimumab concentration, absence of concomitant methotrexate use and biologics switching were associated with a higher AAA titre. The treatment pattern of biologics influences the risk of AAA formation, thereby leading to reduced efficacy of adalimumab. PMID:25673333

  9. An unusual presentation of recurrent uterine rupture during pregnancy

    PubMed Central

    Tan, Shu Qi; Thia, Edwin Wee Hong; Tee, Chee Seng John; Yeo, George Seow Heong

    2015-01-01

    We describe a case of recurrent uterine rupture at the site of a previous rupture. Our patient had a history of right interstitial pregnancy with spontaneous uterine fundal rupture at 18 weeks of pregnancy. During her subsequent pregnancy, she was monitored closely by a senior consultant obstetrician. The patient presented at 34 weeks with right hypochondriac pain. She was clinically stable and fetal monitoring showed no signs of fetal distress. Ultrasonography revealed protrusion of the intact amniotic membranes in the abdominal cavity at the uterine fundus. Uterine rupture is a rare but hazardous obstetric complication. High levels of caution should be exercised in patients with a history of prior uterine rupture, as they may present with atypical symptoms. Ultrasonography could provide valuable information in such cases where there is an elevated risk of uterine rupture at the previous rupture site. PMID:26106245

  10. Can Surgeons Assess CT Suitability for Endovascular Repair (EVAR) in Ruptured Abdominal Aortic Aneurysm? Implications for a Ruptured EVAR Trial

    SciTech Connect

    Rayt, Harjeet Lambert, Kelly; Bown, Matthew; Fishwick, Guy; Morgan, Robert; McCarthy, Mark; London, Nick; Sayers, Robert

    2008-09-15

    The purpose of this study was to determine whether surgeons without formal radiological training are able to assess suitability of patients with ruptured abdominal aortic aneurysms (AAA) for EVAR. The CT scans of 20 patients with AAA were reviewed under timed conditions by six vascular surgeons. Twenty minutes was allocated per scan. They were asked to determine if each aneurysm would be treatable by EVAR in the emergency setting and, if so, to measure for device selection. The results were then compared with those of a vascular radiologist. Six surgeons agreed on the suitability of endovascular repair in 45% of cases (95% CI, 23.1-68.5%; 9/20 scans; {kappa} = 0.41 [p = 0.01]) and concurred with the radiologist in eight of these. Individually, agreement ranged from 13 to 16 of the 20 scans, 65-80% between surgeons. The kappa value for agreement between all the surgeons and the radiologist was 0.47 (p = 0.01, moderate agreement). For the individual surgeons, this ranged from 0.3 to 0.6 (p = 0.01). In conclusion, while overall agreement was moderate between the surgeons and the radiologist, it is clear that if surgeons are to assess patients for ruptured EVAR in the future, focused training of surgical trainees is required.

  11. From AAA to Acuros XB-clinical implications of selecting either Acuros XB dose-to-water or dose-to-medium.

    PubMed

    Zifodya, Jackson M; Challens, Cameron H C; Hsieh, Wen-Long

    2016-06-01

    When implementing Acuros XB (AXB) as a substitute for anisotropic analytic algorithm (AAA) in the Eclipse Treatment Planning System, one is faced with a dilemma of reporting either dose to medium, AXB-Dm or dose to water, AXB-Dw. To assist with decision making on selecting either AXB-Dm or AXB-Dw for dose reporting, a retrospective study of treated patients for head & neck (H&N), prostate, breast and lung is presented. Ten patients, previously treated using AAA plans, were selected for each site and re-planned with AXB-Dm and AXB-Dw. Re-planning was done with fixed monitor units (MU) as well as non-fixed MUs. Dose volume histograms (DVH) of targets and organs at risk (OAR), were analyzed in conjunction with ICRU-83 recommended dose reporting metrics. Additionally, comparisons of plan homogeneity indices (HI) and MUs were done to further highlight the differences between the algorithms. Results showed that, on average AAA overestimated dose to the target volume and OARs by less than 2.0 %. Comparisons between AXB-Dw and AXB-Dm, for all sites, also showed overall dose differences to be small (<1.5 %). However, in non-water biological media, dose differences between AXB-Dw and AXB-Dm, as large as 4.6 % were observed. AXB-Dw also tended to have unexpectedly high 3D maximum dose values (>135 % of prescription dose) for target volumes with high density materials. Homogeneity indices showed that AAA planning and optimization templates would need to be adjusted only for the H&N and Lung sites. MU comparison showed insignificant differences between AXB-Dw relative to AAA and between AXB-Dw relative to AXB-Dm. However AXB-Dm MUs relative to AAA, showed an average difference of about 1.3 % signifying an underdosage by AAA. In conclusion, when dose is reported as AXB-Dw, the effect that high density structures in the PTV has on the dose distribution should be carefully considered. As the results show overall small dose differences between the algorithms, when

  12. Tendon rupture associated with simvastatin/ezetimibe therapy.

    PubMed

    Pullatt, Raja C; Gadarla, Mamatha Reddy; Karas, Richard H; Alsheikh-Ali, Alawi A; Thompson, Paul D

    2007-07-01

    A case of spontaneous biceps tendon rupture in a physician during therapy with the combination of simvastatin and ezetimibe (Vytorin) is reported. Rechallenge produced tendinopathy in the contralateral biceps tendon that abated with drug discontinuation. Tendon rupture generally occurs in injured tendons. Physiological repair of an injured tendon requires degradation and remodeling of the extracellular matrix through matrix metalloproteinases (MMPs). Statins are known to inhibit MMPs. It was hypothesized that statins may increase the risk of tendon rupture by altering MMP activity. In conclusion, statins may increase the risk of tendon rupture by altering MMP activity. PMID:17599460

  13. Differential expression of TRAIL and its receptors relative to calcification in AAA

    SciTech Connect

    Liu, Xun . E-mail: mpscrs@bath.ac.uk; Winrow, Vivienne R.; Horrocks, Michael; Stevens, Cliff R.

    2007-06-22

    Abdominal aortic aneurysm (AAA) is commonly associated with atherosclerosis. Human AAA tissue displays cells undergoing all stages of apoptosis. Tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis in tumour cells but not in normal cells. It has death receptors and decoy receptors. An inhibitor of TRAIL, osteoprotegerin (OPG), is involved in osteogenesis and vascular calcification. We investigated TRAIL and its receptors in AAA compared within normal aorta (NA). Both qualitative and quantitative analyses of calcification in AAA walls were determined using Von Kossa staining and pre-operation computer tomography (CT) scans. There was a significant difference in calcification level at different locations in the AAA wall (p < 0.05). Apoptosis was confirmed in AAA by TUNEL assay. A significant difference in TRAIL and its receptor expression was observed between normal aortae and AAA (p < 0.05). Significant differences were also observed between tissues displaying different extents of calcification for TRAIL mRNA (p < 0.05) by RT-PCR examination and OPG protein (p < 0.01) by protein blotting examination. We propose that this pattern of expression of TRAIL and its receptors may contribute to AAA formation and calcification in the AAA wall.

  14. Chronic Tendonopathy as a Unique Cause of Non Traumatic Triceps Tendon Rupture in a (Risk Factors Free) Bodybuilder: A Case Report

    PubMed Central

    Mangano, Tony; Cerruti, Paola; Repetto, Ilaria; Trentini, Roberto; Giovale, Marcello; Franchin, Francesco

    2015-01-01

    Introduction: Distal triceps tendon rupture is an uncommon lesion rarely due to a non-traumatic mechanism. In these cases, the majority of patients show predisposing factors for tendon degeneration: underlying medical co-morbidities, previous systemic and locally injected corticosteroids and systemic anabolic steroids. A clear evidence for an etiopathogeneticroleforchronictendonopathy in triceps tendon rupture is sti 11 lacking. Case Report: We report the case of a rare non-traumatic complete rupture of the triceps tendon, at the olecranon insertion, occurring in a healthy male middle-aged non-professional bodybuilder. He presented to our attention with a five days history of weakness, swelling and pain at the left elbow, started after a snapping sound during a single arm triceps extension exercise. He was a healthy sportsman, no smoker and no drinker. He had suffered, in the two months before, of mild bilateral exercise-related elbow discomfort, never limiting his sport and daily activities. The man was treated by an early surgical repair. Histological analysis was conducted on intraoperative samples. The treatment allowed complete remission and return to sport practice without functional deficit. Conclusion: An overload-related chronic tendonopathy was identified as the unique factor with causal role in the determinism of the above described lesion. This case highlights, for the first time in literature, that just a chronic tendonopathy, in absence of any other predisposing condition, can lead to a non-traumatic complete triceps tendon rupture. PMID:27299023

  15. Does the A9285G Polymorphism in Collagen Type XII α1 Gene Associate with the Risk of Anterior Cruciate Ligament Ruptures?

    PubMed Central

    Ficek, K; Stepien-Slodkowska, M; Kaczmarczyk, M; Maciejewska-Karlowska, A; Sawczuk, M; Cholewinski, J; Leonska-Duniec, A; Zarebska, A; Cieszczyk, P; Zmijewski, P

    2014-01-01

    One of the most severe injuries sustained by athletes is rupture of the anterior cruciate ligament (ACL). Recent investigations suggest that a predisposition for ACL rupture may be the result of specific genetic sequence variants. In light of this, we decided to investigate whether the COL12A1 A9285G polymorphism was associated with ACL ruptures in Polish football players. We compared genotypic and allelic frequencies of the COL12A1 A9285G polymorphism in two groups of athletes: 91 male football players (23 ± 3 years) with surgically diagnosed primary ACL ruptures who qualified for ligament reconstruction (cases) and 143 apparently healthy, male football players of the same ethnicity, a similar age category, and a comparable level of exposure to ACL injury, who were without any self-reported history of ligament or tendon injury (controls). DNA samples extracted from the oral epithelial cells were genotyped by using a real-time polymerase chain reaction (Ri-Ti-PCR) method. The genotype distribution in the cases were not different from those in controls (p = 0.70). The frequency of the G allele was lower in the cases (18.1%) but not statistically significant (p = 0.40) when compared with controls (21.3%). Our results are in contradiction to the hypothesis that the COL12A1 A9285G polymorphism is associated with a predisposition for ACL injury. However, these conclusions should be supported with more experimental studies on COL12A1 polymorphisms. PMID:25741214

  16. Genital Flora, Prolonged Rupture of the Membranes and the Risk of Early Onset Neonatal Septicemia in Qatif Central Hospital, Kingdom of Saudi Arabia.

    ERIC Educational Resources Information Center

    Srair, Hussain Abu; And Others

    1993-01-01

    Evaluated 108 mothers and their newborn babies for bacterial colonization and neonatal septicemia (NNS) after membranes had ruptured for 24 hours or more. Nearly 40% of the babies were already colonized at birth. The three most common bacteria isolated from the babies were Escherichia coli, Group B Streptococcus, and Streptococcus faecalis. (MDM)

  17. Emerging mechanistic insights into AAA complexes regulating proteasomal degradation.

    PubMed

    Förster, Friedrich; Schuller, Jan M; Unverdorben, Pia; Aufderheide, Antje

    2014-01-01

    The 26S proteasome is an integral element of the ubiquitin-proteasome system(UPS) and, as such, responsible for regulated degradation of proteins in eukaryotic cells.It consists of the core particle, which catalyzes the proteolysis of substrates into small peptides, and the regulatory particle, which ensures specificity for a broad range of substrates.The heart of the regulatory particle is an AAA-ATPase unfoldase, which is surrounded by non-ATPase subunits enabling substrate recognition and processing. Cryo-EM-based studies revealed the molecular architecture of the 26S proteasome and its conformational rearrangements, providing insights into substrate recognition, commitment, deubiquitylation and unfolding. The cytosol proteasomal degradation of polyubiquitylated substrates is tuned by various associating cofactors, including deubiquitylating enzymes, ubiquitin ligases,shuttling ubiquitin receptors and the AAA-ATPase Cdc48/p97. Cdc48/p97 and its cofactors function upstream of the 26S proteasome, and their modular organization exhibits some striking analogies to the regulatory particle. In archaea PAN, the closest regulatory particle homolog and Cdc48 even have overlapping functions, underscoring their intricate relationship.Here, we review recent insights into the structure and dynamics of the 26S proteasome and its associated machinery, as well as our current structural knowledge on the Cdc48/p97 and its cofactors that function in the ubiquitin-proteasome system (UPS). PMID:25102382

  18. Emerging Mechanistic Insights into AAA Complexes Regulating Proteasomal Degradation

    PubMed Central

    Förster, Friedrich; Schuller, Jan M.; Unverdorben, Pia; Aufderheide, Antje

    2014-01-01

    The 26S proteasome is an integral element of the ubiquitin-proteasome system (UPS) and, as such, responsible for regulated degradation of proteins in eukaryotic cells. It consists of the core particle, which catalyzes the proteolysis of substrates into small peptides, and the regulatory particle, which ensures specificity for a broad range of substrates. The heart of the regulatory particle is an AAA-ATPase unfoldase, which is surrounded by non-ATPase subunits enabling substrate recognition and processing. Cryo-EM-based studies revealed the molecular architecture of the 26S proteasome and its conformational rearrangements, providing insights into substrate recognition, commitment, deubiquitylation and unfolding. The cytosol proteasomal degradation of polyubiquitylated substrates is tuned by various associating cofactors, including deubiquitylating enzymes, ubiquitin ligases, shuttling ubiquitin receptors and the AAA-ATPase Cdc48/p97. Cdc48/p97 and its cofactors function upstream of the 26S proteasome, and their modular organization exhibits some striking analogies to the regulatory particle. In archaea PAN, the closest regulatory particle homolog and Cdc48 even have overlapping functions, underscoring their intricate relationship. Here, we review recent insights into the structure and dynamics of the 26S proteasome and its associated machinery, as well as our current structural knowledge on the Cdc48/p97 and its cofactors that function in the ubiquitin-proteasome system (UPS). PMID:25102382

  19. Training Scientists to be Effective Communicators: AAAS Communicating Science Workshops

    NASA Astrophysics Data System (ADS)

    Cendes, L.; Lohwater, T.

    2012-12-01

    "Communicating Science: Tools for Scientists and Engineers" is a workshop program developed by AAAS to provide guidance and practice for scientists and engineers in communicating about science with public audiences. The program was launched at the 2008 AAAS Annual Meeting in Boston and has since provided 24 workshops for more than 1,500 scientist and engineer attendees at universities, science society meetings, and government agency labs around the United States. Each interactive workshop targets scientists and engineers specifically and has included content such as message development, defining audience, identifying opportunities for engaging the public, and practice with public presentations and cameras. The workshop format allows for collaborative learning through small-group discussion, resource sharing, and participation in critique of other participants' presentations. Continuous monitoring of the program includes on-site and online surveys and evaluation. On an assessment of workshops from 2008-2010, attendees reported that knowledge gained from the workshop helped in crafting messages about their scientific work for use in communicating with public audiences, and approximately 80 percent of respondents reported participation in communication with a public audience after attending the workshop. Through workshop content and feedback of participating scientists, this presentation will highlight some best practices and resources for scientists who want to take a proactive role in science communication.

  20. Characterization of the Modular Design of the Autolysin/Adhesin Aaa from Staphylococcus Aureus

    PubMed Central

    Hirschhausen, Nina; Schlesier, Tim; Peters, Georg; Heilmann, Christine

    2012-01-01

    Background Staphylococcus aureus is a frequent cause of serious and life-threatening infections, such as endocarditis, osteomyelitis, pneumonia, and sepsis. Its adherence to various host structures is crucial for the establishment of diseases. Adherence may be mediated by a variety of adhesins, among them the autolysin/adhesins Atl and Aaa. Aaa is composed of three N-terminal repeated sequences homologous to a lysin motif (LysM) that can confer cell wall attachment and a C-terminally located cysteine, histidine-dependent amidohydrolase/peptidase (CHAP) domain having bacteriolytic activity in many proteins. Methodology/Principal Findings Here, we show by surface plasmon resonance that the LysM domain binds to fibrinogen, fibronectin, and vitronectin respresenting a novel adhesive function for this domain. Moreover, we demonstrated that the CHAP domain not only mediates the bacteriolytic activity, but also adherence to fibrinogen, fibronectin, and vitronectin, thus demonstrating for the first time an adhesive function for this domain. Adherence of an S. aureus aaa mutant and the complemented aaa mutant is slightly decreased and increased, respectively, to vitronectin, but not to fibrinogen and fibronectin, which might at least in part result from an increased expression of atl in the aaa mutant. Furthermore, an S. aureus atl mutant that showed enhanced adherence to fibrinogen, fibronectin, and endothelial cells also demonstrated increased aaa expression and production of Aaa. Thus, the redundant functions of Aaa and Atl might at least in part be interchangeable. Lastly, RT-PCR and zymographic analysis revealed that aaa is negatively regulated by the global virulence gene regulators agr and SarA. Conclusions/Significance We identified novel functions for two widely distributed protein domains, LysM and CHAP, i.e. the adherence to the extracellular matrix proteins fibrinogen, fibronectin, and vitronectin. The adhesive properties of Aaa might promote S. aureus

  1. AAA proteases in mitochondria: diverse functions of membrane-bound proteolytic machines.

    PubMed

    Tatsuta, Takashi; Langer, Thomas

    2009-11-01

    FtsH/AAA proteases comprise a distinct family of membrane-bound, ATP-dependent proteases present in eubacteria and eukaryotic cells, where they are confined to mitochondria and chloroplasts. Here, we will summarize versatile functions of AAA proteases within mitochondria, which ensure mitochondrial integrity and cell survival, acting both as quality control and processing enzymes. PMID:19781639

  2. Analysis of a Typical Chinese High School Biology Textbook Using the AAAS Textbook Standards

    ERIC Educational Resources Information Center

    Liang, Ye; Cobern, William W.

    2013-01-01

    The purpose of this study was to evaluate a typical Chinese high school biology textbook using the textbook standards of the American Association for the Advancement of Science (AAAS). The data were composed of three chapters selected from the textbook. Each chapter was analyzed and rated using the AAAS textbook standards. Pearson correlations…

  3. Percutaneous Treatment of Sac Rupture in Abdominal Aortic Aneurysms Previously Excluded with Endovascular Repair (EVAR)

    SciTech Connect

    Lagana, Domenico Mangini, Monica Fontana, Federico; Nicotera, Paolo; Carrafiello, Gianpaolo; Fugazzola, Carlo

    2009-01-15

    The purpose of this study was to assess the feasibility and effectiveness of percutaneous endovascular repair of ruptured abdominal aortic aneurysms (AAAs) previously treated by EVAR. In the last year, two male patients with AAAs, treated 8 and 23 months ago with bifurcated stent-graft, were observed because of lumbar pain and hemorragic shock. Multidetector computed tomography (MDCT) showed a retroperitoneal hematoma; in both cases a type III endoleak was detected, in one case associated with a type II endoleak from the iliolumbar artery. The procedures were performed in the theater, in emergency. Type II endoleak was treated with transcatheter superselective glue injection; type III endoleaks were excluded by a stent-graft extension. The procedures were successful in both patients, with immediate hemodynamic stabilization. MDCT after the procedure showed complete exclusion of the aneurysms. In conclusion, endovascular treatment is a safe and feasible option for the treatment of ruptured AAAs previously treated by EVAR; this approach allows avoidance of surgical conversion, which is technical very challenging, with a high morbidity and mortality rate.

  4. Ultrasound Diagnosis of Bilateral Quadriceps Tendon Rupture After Statin Use

    PubMed Central

    Nesselroade, Ryan D.; Nickels, Leslie Connor

    2010-01-01

    Simultaneous bilateral quadriceps tendon rupture is a rare injury. We report the case of bilateral quadriceps tendon rupture sustained with minimal force while refereeing a football game. The injury was suspected to be associated with statin use as the patient had no other identifiable risk factors. The diagnosis was confirmed using bedside ultrasound. PMID:21079697

  5. Bilateral patellar tendon rupture associated with statin use.

    PubMed

    Kearns, Marie C; Singh, Vinay K

    2016-01-01

    Patellar tendon rupture is an uncommon clinical presentation, which generally affects the under 40s who are active in sport. Bilateral rupture of both tendons is much rarer. It occurs most frequently in patients with predisposing factors such as corticosteroid use or systemic diseases. The authors present the case of a 56-year-old male on long-term statin therapy who sustained this injury following a fall on ice. He had no known risk factors for tendon rupture. Surgical treatment involved tendon repair using Krakow suture via bony tunnels in the patella. Statins have previously been associated with tendon ruptures at other sites but there have been no published cases of bilateral patellar tendon rupture linked to statin use. We review the literature regarding the association between statins and tendon rupture. PMID:27165749

  6. Bilateral patellar tendon rupture associated with statin use

    PubMed Central

    Kearns, Marie C.; Singh, Vinay K.

    2016-01-01

    Patellar tendon rupture is an uncommon clinical presentation, which generally affects the under 40s who are active in sport. Bilateral rupture of both tendons is much rarer. It occurs most frequently in patients with predisposing factors such as corticosteroid use or systemic diseases. The authors present the case of a 56-year-old male on long-term statin therapy who sustained this injury following a fall on ice. He had no known risk factors for tendon rupture. Surgical treatment involved tendon repair using Krakow suture via bony tunnels in the patella. Statins have previously been associated with tendon ruptures at other sites but there have been no published cases of bilateral patellar tendon rupture linked to statin use. We review the literature regarding the association between statins and tendon rupture. PMID:27165749

  7. Fault rupture segmentation

    NASA Astrophysics Data System (ADS)

    Cleveland, Kenneth Michael

    A critical foundation to earthquake study and hazard assessment is the understanding of controls on fault rupture, including segmentation. Key challenges to understanding fault rupture segmentation include, but are not limited to: What determines if a fault segment will rupture in a single great event or multiple moderate events? How is slip along a fault partitioned between seismic and seismic components? How does the seismicity of a fault segment evolve over time? How representative are past events for assessing future seismic hazards? In order to address the difficult questions regarding fault rupture segmentation, new methods must be developed that utilize the information available. Much of the research presented in this study focuses on the development of new methods for attacking the challenges of understanding fault rupture segmentation. Not only do these methods exploit a broader band of information within the waveform than has traditionally been used, but they also lend themselves to the inclusion of even more seismic phases providing deeper understandings. Additionally, these methods are designed to be fast and efficient with large datasets, allowing them to utilize the enormous volume of data available. Key findings from this body of work include demonstration that focus on fundamental earthquake properties on regional scales can provide general understanding of fault rupture segmentation. We present a more modern, waveform-based method that locates events using cross-correlation of the Rayleigh waves. Additionally, cross-correlation values can also be used to calculate precise earthquake magnitudes. Finally, insight regarding earthquake rupture directivity can be easily and quickly exploited using cross-correlation of surface waves.

  8. Loss of Drosophila i-AAA protease, dYME1L, causes abnormal mitochondria and apoptotic degeneration.

    PubMed

    Qi, Y; Liu, H; Daniels, M P; Zhang, G; Xu, H

    2016-02-01

    Mitochondrial AAA (ATPases Associated with diverse cellular Activities) proteases i-AAA (intermembrane space-AAA) and m-AAA (matrix-AAA) are closely related and have major roles in inner membrane protein homeostasis. Mutations of m-AAA proteases are associated with neuromuscular disorders in humans. However, the role of i-AAA in metazoans is poorly understood. We generated a deletion affecting Drosophila i-AAA, dYME1L (dYME1L(del)). Mutant flies exhibited premature aging, progressive locomotor deficiency and neurodegeneration that resemble some key features of m-AAA diseases. dYME1L(del) flies displayed elevated mitochondrial unfolded protein stress and irregular cristae. Aged dYME1L(del) flies had reduced complex I (NADH/ubiquinone oxidoreductase) activity, increased level of reactive oxygen species (ROS), severely disorganized mitochondrial membranes and increased apoptosis. Furthermore, inhibiting apoptosis by targeting dOmi (Drosophila Htra2/Omi) or DIAP1, or reducing ROS accumulation suppressed retinal degeneration. Our results suggest that i-AAA is essential for removing unfolded proteins and maintaining mitochondrial membrane architecture. Loss of i-AAA leads to the accumulation of oxidative damage and progressive deterioration of membrane integrity, which might contribute to apoptosis upon the release of proapoptotic molecules such as dOmi. Containing ROS level could be a potential strategy to manage mitochondrial AAA protease deficiency. PMID:26160069

  9. Patient specific stress and rupture analysis of ascending thoracic aneurysms.

    PubMed

    Trabelsi, Olfa; Davis, Frances M; Rodriguez-Matas, Jose F; Duprey, Ambroise; Avril, Stéphane

    2015-07-16

    An ascending thoracic aortic aneurysm (ATAA) is a serious medical condition which, more often than not, requires surgery. Aneurysm diameter is the primary clinical criterion for determining when surgical intervention is necessary but, biomechanical studies have suggested that the diameter criterion is insufficient. This manuscript presents a method for obtaining the patient specific wall stress distribution of the ATAA and the retrospective rupture risk for each patient. Five human ATAAs and the preoperative dynamic CT scans were obtained during elective surgeries to replace each patient's aneurysm with a synthetic graft. The material properties and rupture stress for each tissue sample were identified using bulge inflation tests. The dynamic CT scans were used to generate patient specific geometries for a finite element (FE) model of each patient's aneurysm. The material properties from the bulge inflation tests were implemented in the FE model and the wall stress distribution at four different pressures was estimated. Three different rupture risk assessments were compared: the maximum diameter, the rupture risk index, and the overpressure index. The peak wall stress values for the patients ranged from 28% to 94% of the ATAA's failure stress. The rupture risk and overpressure indices were both only weakly correlated with diameter (ρ=-0.29, both cases). In the future, we plan to conduct a large experimental and computational study that includes asymptomatic patients under surveillance, patients undergoing elective surgery, and patients who have experienced rupture or dissection to determine if the rupture risk index or maximum diameter can meaningfully differentiate between the groups. PMID:25979384

  10. The effect of aortic morphology on peri-operative mortality of ruptured abdominal aortic aneurysm

    PubMed Central

    2015-01-01

    Aims To investigate whether aneurysm shape and extent, which indicate whether a patient with ruptured abdominal aortic aneurysm (rAAA) is eligible for endovascular repair (EVAR), influence the outcome of both EVAR and open surgical repair. Methods and results The influence of six morphological parameters (maximum aortic diameter, aneurysm neck diameter, length and conicality, proximal neck angle, and maximum common iliac diameter) on mortality and reinterventions within 30 days was investigated in rAAA patients randomized before morphological assessment in the Immediate Management of the Patient with Rupture: Open Versus Endovascular strategies (IMPROVE) trial. Patients with a proven diagnosis of rAAA, who underwent repair and had their admission computerized tomography scan submitted to the core laboratory, were included. Among 458 patients (364 men, mean age 76 years), who had either EVAR (n = 177) or open repair (n = 281) started, there were 155 deaths and 88 re-interventions within 30 days of randomization analysed according to a pre-specified plan. The mean maximum aortic diameter was 8.6 cm. There were no substantial correlations between the six morphological variables. Aneurysm neck length was shorter in those undergoing open repair (vs. EVAR). Aneurysm neck length (mean 23.3, SD 16.1 mm) was inversely associated with mortality for open repair and overall: adjusted OR 0.72 (95% CI 0.57, 0.92) for each 16 mm (SD) increase in length. There were no convincing associations of morphological parameters with reinterventions. Conclusion Short aneurysm necks adversely influence mortality after open repair of rAAA and preclude conventional EVAR. This may help explain why observational studies, but not randomized trials, have shown an early survival benefit for EVAR. Clinical trial registration: ISRCTN 48334791. PMID:25627357

  11. Arachnoid cyst spontaneous rupture.

    PubMed

    Marques, Inês Brás; Vieira Barbosa, José

    2014-01-01

    Arachnoid cysts are benign congenital cerebrospinal fluid collections, usually asymptomatic and diagnosed incidentally in children or adolescents. They may become symptomatic after enlargement or complications, frequently presenting with symptoms of intracranial hypertension. We report an unusual case of progressive refractory headache in an adult patient due to an arachnoid cyst spontaneous rupture. Although clinical improvement occurred with conservative treatment, the subdural hygroma progressively enlarged and surgical treatment was ultimately needed. Spontaneous rupture is a very rare complication of arachnoid cysts. Accumulation of cerebrospinal fluid accumulation in the subdural space causes sustained intracranial hypertension that may be life-threatening and frequently requires surgical treatment. Patients with arachnoid cysts must be informed on their small vulnerability to cyst rupture and be aware that a sudden and severe headache, especially if starting after minor trauma or a Valsalva manoeuvre, always requires medical evaluation. PMID:24581205

  12. Component external leakage and rupture frequency estimates

    SciTech Connect

    Eide, S.A.; Khericha, S.T.; Calley, M.B.; Johnson, D.A.; Marteeny, M.L.

    1991-11-01

    In order to perform detailed internal flooding risk analyses of nuclear power plants, external leakage and rupture frequencies are needed for various types of components - piping, valves, pumps, flanges, and others. However, there appears to be no up-to-date, comprehensive source for such frequency estimates. This report attempts to fill that void. Based on a comprehensive search of Licensee Event Reports (LERs) contained in Nuclear Power Experience (NPE), and estimates of component populations and exposure times, component external leakage and rupture frequencies were generated. The remainder of this report covers the specifies of the NPE search for external leakage and rupture events, analysis of the data, a comparison with frequency estimates from other sources, and a discussion of the results.

  13. Postmyomectomic Uterine Rupture Despite Cesarean Section.

    PubMed

    Kacperczyk, Joanna; Bartnik, Paweł; Romejko-Wolniewicz, Ewa; Dobrowolska-Redo, Agnieszka

    2016-03-01

    Uterine fibroids (leiomyomas) are benign smooth muscle tumors of the uterus. Fibroids can develop anywhere within the muscular wall. Leiomyomas may be associated with infertility. Laparoscopic myomectomy is often used to remove symptomatic intramural or subserosal fibroids. Advantages of the procedure include short recovery time and minimal perioperative morbidity. At the same time, the multilayer suture technique is more complicated during laparoscopy. A rare but serious complication of laparoscopic myomectomies is uterine rupture. A brief review of the literature and a clinical example of a 33-year-old woman with history of infertility, laparoscopic myomectomies and uterine rupture followed by peripartum hemorrhage is presented. The treatment of leiomyomas is a challenge not only because of possible recurrence but also due to long-term consequences following successful myomectomy. Management of patients with uterine scars should include careful planning of the route of delivery, as the risk of rupture may be increased. PMID:26976991

  14. Spontaneous Uterine Rupture in the First Trimester: A Case Report

    PubMed Central

    Ryu, Ki-Young; Lee, Jong-In; Park, Moon-Il

    2005-01-01

    Uterine rupture is one of the most feared obstetric complications affecting the pregnant woman and fetus. Most of the cases have various risk factors and mainly occur during the second or third trimester. However, spontaneous uterine rupture during the first trimester is extremely rare. We experienced a case of spontaneous uterine rupture in a 36-yr-old multiparous woman without definite risk factors. The initial impression was a hemoperitoneum of an unknown origin with normal early pregnancy. Intensive surgical method would be needed for accurate diagnosis and immediate management in bad situation by hemoperitoneum even though a patient was early pregnancy. PMID:16361828

  15. Modelling of residually stressed materials with application to AAA.

    PubMed

    Ahamed, T; Dorfmann, L; Ogden, R W

    2016-08-01

    Residual stresses are generated in living tissues by processes of growth and adaptation and they significantly influence the mechanical behaviour of the tissues. Thus, to effectively model the elastic response of the tissues relative to a residually stressed configuration the residual stresses need to be incorporated into the constitutive equations. The purposes of this paper are (a) to summarise a general elastic constitutive formulation that includes residual stress, (b) to specify the tensors needed for the three-dimensional implementation of the theory in a nonlinear finite element code, and (c) to use the theory and its implementation to evaluate the wall stress distribution in an abdominal aortic aneurysm (AAA) using patient specific geometry and material model parameters. The considered material is anisotropic with two preferred directions indicating the orientation of the collagen fibres in the aortic tissue. The method described in this paper is general and can be used, by specifying appropriate energy functions, to investigate other residually stressed biological systems. PMID:26874252

  16. AAA: Road Debris a Mounting Danger on U.S. Highways

    MedlinePlus

    ... Highways Crashes involving objects that have fallen from vehicles up 40 percent since 2001 To use the ... the AAA Foundation for Traffic Safety. Crashes involving vehicle-related debris are up 40 percent since the ...

  17. Spontaneous Posterior Uterine Rupture in Twin-Twin Transfusion Syndrome

    PubMed Central

    Smid, Marcela C.; Waltner-Toews, Rebecca; Goodnight, William

    2015-01-01

    Background The maternal and fetal risks of uterine distension in rapidly progressive twin-twin transfusion syndrome (TTTS) in the setting of prior uterine scar are poorly characterized. Case We present the case of a 42-year-old woman, G4P1201, at 21 weeks gestation with stage-1 TTTS who developed a spontaneous posterior uterine rupture necessitating emergent laparotomy and delivery of previable fetuses, possibly due to prior uterine scar from a displaced intrauterine device. Conclusion TTTS may be a risk factor for uterine rupture, including uterine rupture in atypical anatomic locations. Prior unrecognized uterine scars, including perforations, may magnify the risk for atypical uterine rupture in the setting of excessive uterine distension. PMID:26929874

  18. Gastric rupture in horses: 50 cases (1979-1987).

    PubMed

    Kiper, M L; Traub-Dargatz, J; Curtis, C R

    1990-01-15

    A computer-based search was conducted of medical and necropsy records of horses admitted to the teaching hospital from Jan 1, 1979, to Dec 31, 1987, to obtain the records of all horses admitted to the hospital for colic and subsequently found to have gastric rupture. Fifty cases of gastric rupture were found. The records were reviewed to obtain data regarding peritoneal fluid analysis. Cell counts of these samples were often erroneous because debris and clumps of bacteria were counted when most WBC were lysed. A cross-sectional study of gastric rupture cases versus all other colic cases regarding season of admission revealed that there was no association between season and the occurrence of gastric rupture. There was also no increased risk associated with age, gender, breed, and the occurrence of gastric rupture. One hundred colic cases, matched with the gastric rupture cases by year of admission, were randomly selected via a table of random numbers. A questionnaire regarding age, breed, gender, use of the horse, housing, diet, water source, deworming schedule, and medical history was completed from the medical records and phone conversations with the horse owners. The results indicated that horses on a diet of grass hay or grass/alfalfa hay only or those that drank water from a bucket, stream, or pond were at increased risk for having gastric rupture. In contrast, horses fed grain had a reduced risk. PMID:2298661

  19. Surgical repair of ruptured abdominal aortic aneurysm with non-bleeding aortocaval fistula.

    PubMed

    Unosawa, Satoshi; Kimura, Haruka; Niino, Tetsuya

    2013-01-01

    We present a case of an aortocaval fistula (ACF) without bleeding because a clot was covering the fistula. A 60-year-old man was diagnosed as having a ruptured abdominal aortic aneurysm (AAA) and an aortocaval fistula, by enhanced computed tomography (CT). After the aneurysm had been opened, the fistula was detected, but there was no bleeding because it was covered with clot. After graft repair, bleeding from the fistula occurred when the clot was removed by suction. Direct closure of the fistula was achieved after bleeding was controlled by digital compression. PMID:23825505

  20. Consequences of expansion joint bellows rupture

    SciTech Connect

    Daugherty, W.L.; Miller, R.F.; Cramer, D.S.

    1992-01-01

    Expansion joints are used in piping systems to accommodate pipe deflections during service and to facilitate fitup. Typically, the expansion joint bellows is the thinnest part of the pressure boundary, bellows rupture frequencies are typically several orders of magnitude higher than pipe rupture frequencies. This paper reviews an effort to estimate the flow rates associated with bellows rupture. The Level I PRA (probabilistic risk assessment) for the Savannah River Site production reactors made the bounding assumption that bellows rupture would produce the maximum possible leakage - that of a double-ended guillotine break (DEGB). This assumption resulted in predictions of flooding of the reactor building with a high conditional probability that a Loss of Pumping Accident and core melting would follow. This paper describes analyses that were performed to develop a realistic break area and leak rate resulting from bellows rupture and therefore reduce the impact that bellows rupture can have on the estimated total core melt frequency. In the event of a 360 degree circumferential break of the bellows the resulting two sections will separate to the point where the force from the internal pressure acting to push the bellows open is just balanced by the spring force of the bellows itself. For the bellows addressed in this analysis, the equilibrium separation distance is 0.7 inches with normal pump lineup. The opening area is influenced by any initial compression or extension due to installation alignment, and by any operational displacements such as thermal expansion of the adjoining pipe. The influence of such factors is considered and the impact on the flooding rate and, hence, core melt frequency is reviewed.

  1. Consequences of expansion joint bellows rupture

    SciTech Connect

    Daugherty, W.L.; Miller, R.F.; Cramer, D.S.

    1992-11-01

    Expansion joints are used in piping systems to accommodate pipe deflections during service and to facilitate fitup. Typically, the expansion joint bellows is the thinnest part of the pressure boundary, bellows rupture frequencies are typically several orders of magnitude higher than pipe rupture frequencies. This paper reviews an effort to estimate the flow rates associated with bellows rupture. The Level I PRA (probabilistic risk assessment) for the Savannah River Site production reactors made the bounding assumption that bellows rupture would produce the maximum possible leakage - that of a double-ended guillotine break (DEGB). This assumption resulted in predictions of flooding of the reactor building with a high conditional probability that a Loss of Pumping Accident and core melting would follow. This paper describes analyses that were performed to develop a realistic break area and leak rate resulting from bellows rupture and therefore reduce the impact that bellows rupture can have on the estimated total core melt frequency. In the event of a 360 degree circumferential break of the bellows the resulting two sections will separate to the point where the force from the internal pressure acting to push the bellows open is just balanced by the spring force of the bellows itself. For the bellows addressed in this analysis, the equilibrium separation distance is 0.7 inches with normal pump lineup. The opening area is influenced by any initial compression or extension due to installation alignment, and by any operational displacements such as thermal expansion of the adjoining pipe. The influence of such factors is considered and the impact on the flooding rate and, hence, core melt frequency is reviewed.

  2. A Three Year Clinicopathological Study of Cases of Rupture Uterus

    PubMed Central

    Rathod, Setu; Swain, Sujata

    2015-01-01

    Introduction Rupture uterus is a life threatening obstetric complication with serious maternal and fetal side-effects. We report a 3 year (2010-2013) retrospective clinical study of pregnancy with rupture uterus cases attending a tertiary care hospital. Aim The aim of the study was to evaluate the incidence of rupture uterus, incidence as per age, parity, clinical presentations, risk factors, complications and management. Materials and Methods Retrospective data of 74 cases of rupture uterus in SCB Medical college, Cuttack was collected from case records of 26,547 deliveries during a 3 year span (2010-2013). Parameters like cause of rupture, type, site of rupture and outcome were recorded. The collected data was analysed by SPSS software v19. Results Out of 26,547 deliveries during the three year period, there were 74 cases of rupture uterus with an incidence of rupture 1 in 359 (0.28%). The mean age of rupture uterus was 27.4 years. 95.8% were multigravida and majority were referred cases from low socioeconomic status. Only 40.5% had the required minimum of four antenatal visits as recommended by WHO (World Health Organisation). A total of 48.6% of cases with rupture uterus had history of previous Caesarean section. Prolonged labour was present in 75.6% of the cases. Only 12.2% of the cases had history of oxytocin use whereas 9.5% had undergone an operative vaginal delivery. Obstructed labour was the cause in 24.3% of cases, 85.1% had complete rupture. Majority had a rupture in the anterior wall (69%) and 81.1% had rupture in lower segment of uterus. Only 17.6% had broad ligament haematoma, 10.8% colporrhexis and 6.8% had associated bladder injury. Repair was possible in only 39.2% of cases, whereas majority landed up in hysterectomy. Internal iliac ligation was done in 2.7% of cases. Perinatal mortality was 90.5% whereas maternal death was seen in 13.5% cases. One patient developed VVF (vesicovaginal fistula). Duration of hospital stay was upto 14 days in 81

  3. Engineering Silicone Rubbers for In vitro Studies: Creating AAA Models and ILT Analogues with Physiological Properties

    PubMed Central

    Corbett, T.J.; Doyle, B.J.; Callanan, A.; Walsh, M.T.; McGloughlin, T.M

    2010-01-01

    Background In vitro studies of abdominal aortic aneurysm (AAA) have been widely reported. Frequently mock artery models with intraluminal thrombus (ILT) analogues are used to mimic the AAA in vivo. While the models used may be physiological, their properties are frequently either not reported or investigated. Method of Approach This study is concerned with the testing and characterisation of previously used vessel analogue materials and the development of new materials for the manufacture of AAA models. These materials were used in conjunction with a previously validated injection moulding technique to manufacture AAA models of ideal geometry. To determine the model properties (stiffness (β) and compliance) the diameter change of each AAA model was investigated under incrementally increasing internal pressures and compared to published in vivo studies to determine if the models behaved physiologically. A FEA study was implemented to determine if the pressure – diameter change behaviour of the models could be predicted numerically. ILT analogues were also manufactured and characterised. Ideal models were manufactured with ILT analogue internal to the aneurysm region and the effect of the ILT analogue on the model compliance and stiffness was investigated. Results The wall materials had similar properties to aortic tissue at physiological pressures (Einit 2.22MPa and 1.57MPa (aortic tissue: 1.8MPa)). ILT analogues had similar Young’s modulus to the medial layer of ILT (0.24 and 0.33MPa (ILT: 0.28MPa)). All models had aneurysm sac compliance in the physiological range (2.62 – 8.01×10-4/mmHg (AAA in vivo: 1.8 – 9.4×10-4/mmHg)). The necks of our AAA models had similar stiffness to healthy aortas (20.44 – 29.83 (healthy aortas in vivo: 17.5±5.5)). Good agreement was seen between the diameter changes due to pressurisation in the experimental and FEA wall models with a maximum error of 7.3% at 120mmHg. It was also determined that the inclusion of ILT analogue

  4. Verification of IMRT dose calculations using AAA and PBC algorithms in dose buildup regions.

    PubMed

    Oinam, Arun S; Singh, Lakhwant

    2010-01-01

    The purpose of this comparative study was to test the accuracy of anisotropic analytical algorithm (AAA) and pencil beam convolution (PBC) algorithms of Eclipse treatment planning system (TPS) for dose calculations in the low- and high-dose buildup regions. AAA and PBC algorithms were used to create two intensity-modulated radiotherapy (IMRT) plans of the same optimal fluence generated from a clinically simulated oropharynx case in an in-house fabricated head and neck phantom. The TPS computed buildup doses were compared with the corresponding measured doses in the phantom using thermoluminescence dosimeters (TLD 100). Analysis of dose distribution calculated using PBC and AAA shows an increase in gamma value in the dose buildup region indicating large dose deviation. For the surface areas of 1, 50 and 100 cm2, PBC overestimates doses as compared to AAA calculated value in the range of 1.34%-3.62% at 0.6 cm depth, 1.74%-2.96% at 0.4 cm depth, and 1.96%-4.06% at 0.2 cm depth, respectively. In high-dose buildup region, AAA calculated doses were lower by an average of -7.56% (SD = 4.73%), while PBC was overestimated by 3.75% (SD = 5.70%) as compared to TLD measured doses at 0.2 cm depth. However, at 0.4 and 0.6 cm depth, PBC overestimated TLD measured doses by 5.84% (SD = 4.38%) and 2.40% (SD = 4.63%), respectively, while AAA underestimated the TLD measured doses by -0.82% (SD = 4.24%) and -1.10% (SD = 4.14%) at the same respective depth. In low-dose buildup region, both AAA and PBC overestimated the TLD measured doses at all depths except -2.05% (SD = 10.21%) by AAA at 0.2 cm depth. The differences between AAA and PBC at all depths were statistically significant (p < 0.05) in high-dose buildup region, whereas it is not statistically significant in low-dose buildup region. In conclusion, AAA calculated the dose more accurately than PBC in clinically important high-dose buildup region at 0.4 cm and 0.6 cm depths. The use of an orfit cast increases the dose buildup

  5. Blunt cardiac rupture.

    PubMed

    Martin, T D; Flynn, T C; Rowlands, B J; Ward, R E; Fischer, R P

    1984-04-01

    Blunt injury to the heart ranges from contusion to disruption. This report comprises 14 patients seen during a 6-year period with cardiac rupture secondary to blunt trauma. Eight patients were injured in automobile accidents, two patients were injured in auto-pedestrian accidents, two were kicked in the chest by ungulates, and two sustained falls. Cardiac tamponade was suspected in ten patients. Five patients presented with prehospital cardiac arrest or arrested shortly after arrival. All underwent emergency department thoracotomy without survival. Two patients expired in the operating room during attempted cardiac repair; both had significant extracardiac injury. Seven patients survived, three had right atrial injuries, three had right ventricular injuries, and one had a left atrial injury. Cardiopulmonary bypass was not required for repair of the surviving patients. There were no significant complications from the cardiac repair. The history of significant force dispersed over a relatively small area of the precordium as in a kicking injury from an animal or steering wheel impact should alert the physician to possible cardiac rupture. Cardiac rupture should be considered in patients who present with signs of cardiac tamponade or persistent thoracic bleeding after blunt trauma. PMID:6708151

  6. Premature rupture of membranes.

    PubMed Central

    Poma, P. A.

    1996-01-01

    The management of patients with premature rupture of membranes has changed markedly in the past several years. The basis for this is a combination of a better understanding of newborn physiology, improved neonatal care, refinements in antibiotic therapy, and the widespread use of maternal and fetal monitoring. The best outcome for both mother and infant undoubtedly reflects data based on a combination of factors, among which are gestational age survival, evidence of fetal distress, presence or absence of labor and sepsis, and of course, the cervical condition as it is related to labor-readiness. An important recent advance is the recognition that an active observation management program is associated with less morbidity and mortality than the classic management course of delivery within 12 hours of membrane rupture. The fact that preterm premature rupture of membranes tends to recur in subsequent pregnancies offers an opportunity for prevention. Moreover, advances in perinatal and neonatal care will continue to improve the outcomes of these women and their children. PMID:8583489

  7. Prediction of Severe Eye Injuries in Automobile Accidents: Static and Dynamic Rupture Pressure of the Eye

    PubMed Central

    Kennedy, Eric A.; Voorhies, Katherine D.; Herring, Ian P.; Rath, Amber L.; Duma, Stefan M.

    2004-01-01

    The purpose of this paper is to determine the static and dynamic rupture pressures of 20 human and 20 porcine eyes. This study found the static test results show an average rupture pressure for porcine eyes of 1.00 ± 0.18 MPa while the average rupture pressure for human eyes was 0.36 ± 0.20 MPa. For dynamic loading, the average porcine rupture pressure was 1.64 ± 0.32 MPa, and the average rupture pressure for human eyes was 0.91 ± 0.29 MPa. Significant differences are found between average rupture pressures from all four groups of tests (p = 0.01). A risk function has been developed and predicts a 50% risk of globe rupture at 1.02 MPa, 1.66 MPa, 0.35 MPa, and 0.90 MPa internal pressure for porcine static, porcine dynamic, human static, and human dynamic loading conditions, respectively. PMID:15319124

  8. Perianeurysmal edema as a predictive sign of aneurysmal rupture.

    PubMed

    Pahl, Felix Hendrik; de Oliveira, Matheus Fernandes; Ferreira, Nelson Paes Fortes Diniz; de Macedo, Leonardo Lopes; Brock, Roger Schmidt; de Souza, Valéria Cardoso

    2014-11-01

    Subarachnoid hemorrhage following intracranial aneurysmal rupture is a major cause of morbidity and mortality. Several factors may affect the probability of rupture, such as tobacco and alcohol use; size, shape, and location of the aneurysm; presence of intraluminal thrombus; and even the sex of the patient. However, few data correlate such findings with the timing of aneurysmal rupture. The authors report 2 cases of middle-age women with headache and MRI findings of incidental aneurysms. Magnetic resonance imaging showed evidence of surrounding parenchymal edema, and in one case there was a clear increase in edema during follow-up, suggesting a progressive inflammatory process that culminated with rupture. These findings raise the possibility that bleb formation and an enlargement of a cerebral aneurysm might be associated with an inflammatory reaction of the aneurysm wall resulting in perianeurysmal edema and subsequent aneurysmal rupture. There may be a temporal link between higher degree of edema and higher risk for rupture, including risk for immediate rupture. PMID:25036206

  9. In vitro analysis of localized aneurysm rupture.

    PubMed

    Romo, Aaron; Badel, Pierre; Duprey, Ambroise; Favre, Jean-Pierre; Avril, Stéphane

    2014-02-01

    In this study, bulge inflation tests were used to characterize the failure response of 15 layers of human ascending thoracic aortic aneurysms (ATAA). Full field displacement data were collected during each of the mechanical tests using a digital image stereo-correlation (DIS-C) system. Using the collected displacement data, the local stress fields at burst were derived and the thickness evolution was estimated during the inflation tests. It was shown that rupture of the ATAA does not systematically occur at the location of maximum stress, but in a weakened zone of the tissue where the measured fields show strain localization and localized thinning of the wall. Our results are the first to show the existence of weakened zones in the aneurysmal tissue when rupture is imminent. An understanding these local rupture mechanics is necessary to improve clinical assessments of aneurysm rupture risk. Further studies must be performed to determine if these weakened zones can be detected in vivo using non-invasive techniques. PMID:24406100

  10. 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

  11. Cytoplasmic dynein regulates its attachment to microtubules via nucleotide state-switched mechanosensing at multiple AAA domains.

    PubMed

    Nicholas, Matthew P; Berger, Florian; Rao, Lu; Brenner, Sibylle; Cho, Carol; Gennerich, Arne

    2015-05-19

    Cytoplasmic dynein is a homodimeric microtubule (MT) motor protein responsible for most MT minus-end-directed motility. Dynein contains four AAA+ ATPases (AAA: ATPase associated with various cellular activities) per motor domain (AAA1-4). The main site of ATP hydrolysis, AAA1, is the only site considered by most dynein motility models. However, it remains unclear how ATPase activity and MT binding are coordinated within and between dynein's motor domains. Using optical tweezers, we characterize the MT-binding strength of recombinant dynein monomers as a function of mechanical tension and nucleotide state. Dynein responds anisotropically to tension, binding tighter to MTs when pulled toward the MT plus end. We provide evidence that this behavior results from an asymmetrical bond that acts as a slip bond under forward tension and a slip-ideal bond under backward tension. ATP weakens MT binding and reduces bond strength anisotropy, and unexpectedly, so does ADP. Using nucleotide binding and hydrolysis mutants, we show that, although ATP exerts its effects via binding AAA1, ADP effects are mediated by AAA3. Finally, we demonstrate "gating" of AAA1 function by AAA3. When tension is absent or applied via dynein's C terminus, ATP binding to AAA1 induces MT release only if AAA3 is in the posthydrolysis state. However, when tension is applied to the linker, ATP binding to AAA3 is sufficient to "open" the gate. These results elucidate the mechanisms of dynein-MT interactions, identify regulatory roles for AAA3, and help define the interplay between mechanical tension and nucleotide state in regulating dynein motility. PMID:25941405

  12. Ruptured tubal molar pregnancy.

    PubMed

    Yakasai, I A; Adamu, N; Galadanchi, H S

    2012-01-01

    Molar pregnancies in most instances develop within the uterine cavity, but may occur at any site. Ectopic molar pregnancy is a rare event. The objective of this study was to present a case of ruptured tubal molar gestation, discuss its clinical features and ways to improve diagnostic accuracy. A 35-year-old woman presented with features suggestive of ruptured tubal ectopic pregnancy. There was neither any evidence at the time of presentation to suspect a molar gestation, nor β human chorionic gonadotrophin (βhCG) hormone estimation was done, but only a clearview pregnancy test was carried out. She had total left salpingectomy and histological evaluation of the specimen revealed complete hydatidiform mole. The hCG level normalized within 3 weeks of follow-up. Clinical features of ectopic molar pregnancy may be indistinguishable from non-molar ectopic pregnancy. We recommend βhCG estimation as well as histological examination of the surgical specimen for all patients coming with features suggestive of ectopic pregnancy. PMID:23238205

  13. Role of mitochondrial processing peptidase and AAA proteases in processing of the yeast acetohydroxyacid synthase precursor.

    PubMed

    Dasari, Suvarna; Kölling, Ralf

    2016-07-01

    We studied presequence processing of the mitochondrial-matrix targeted acetohydroxyacid synthase (Ilv2). C-terminal 3HA-tagging altered the cleavage pattern from a single step to sequential two-step cleavage, giving rise to two Ilv2-3HA forms (A and B). Both cleavage events were dependent on the mitochondrial processing peptidase (MPP). We present evidence for the involvement of three AAA ATPases, m- and i-AAA proteases, and Mcx1, in Ilv2-3HA processing. Both, precursor to A-form and A-form to B-form cleavage were strongly affected in a ∆yme1 mutant. These defects could be suppressed by overexpression of MPP, suggesting that MPP activity is limiting in the ∆yme1 mutant. Our data suggest that for some substrates AAA ATPases could play an active role in the translocation of matrix-targeted proteins. PMID:27398316

  14. Spontaneous rupture on irregular faults

    NASA Astrophysics Data System (ADS)

    Liu, C.

    2014-12-01

    It is now know (e.g. Robinson et al., 2006) that when ruptures propagate around bends, the rupture velocity decrease. In the extreme case, a large bend in the fault can stop the rupture. We develop a 2-D finite difference method to simulate spontaneous dynamic rupture on irregular faults. This method is based on a second order leap-frog finite difference scheme on a uniform mesh of triangles. A relaxation method is used to generate an irregular fault geometry-conforming mesh from the uniform mesh. Through this numerical coordinate mapping, the elastic wave equations are transformed and solved in a curvilinear coordinate system. Extensive numerical experiments using the linear slip-weakening law will be shown to demonstrate the effect of fault geometry on rupture properties. A long term goal is to simulate the strong ground motion near the vicinity of bends, jogs, etc.

  15. Multi-Canister overpack necessity of the rupture disk

    SciTech Connect

    SMITH, K.E.

    1998-11-03

    The Multi-Canister Overpack (MCO) rupture disk precludes the MCO from pressurization above the design limit during transport from the K Basins to the Cold Vacuum Drying (CVD) Facility and prior to connection of the CVD process piping. Removal of the rupture disk from the MCO design would: (a) result in unacceptable dose consequences in the event a thermal runaway accident occurred; (b) increase residual risk; and (c) remove a degree of specificity from the dose calculations. The potential cost savings of removing the rupture disk from the MCO design is offset by the cost of design modifications, changes to hazard analyses and safety analyses, and changes to existing documentation. Retaining the rupture disk mitigates the consequences of MCO overpressurization, and considering the overall economic impacts to the SNF Project, is the most cost effective approach.

  16. Splenic rupture as a presenting feature of endocarditis.

    PubMed

    Winearls, James Roger; McGloughlin, Steven; Fraser, John F

    2009-04-01

    We describe the first case of infective endocarditis presenting with spontaneous splenic rupture. Our patient, a known intravenous drug user presented with hypovolaemic shock secondary to splenic rupture. The patient was resuscitated and underwent an emergency splenectomy. Subsequent clinical examination revealed a systolic murmur and a diagnosis of mitral valve infective endocarditis was made after echocardiography. Splenic tissue, blood cultures and mitral valve tissue all cultured Enterococcus faecalis. The patient had a successful mitral valve replacement and was discharged home after 44 days. To our knowledge this is the first reported case of enterococcal endocarditis presenting with splenic rupture. This case highlights the need to consider endocarditis in spontaneous splenic rupture particularly in those patients in a high risk group, such as IV drug users, especially if they lack a clear history of trauma. PMID:19217796

  17. Spontaneous Iliac Vein Rupture

    PubMed Central

    Kim, Dae Hwan; Park, Hyung Sub; Lee, Taeseung

    2015-01-01

    Spontaneous iliac vein rupture (SIVR) is a rare entity, which usually occurs without a precipitating factor, but can be a life-threatening emergency often requiring an emergency operation. This is a case report of SIVR in a 62-year-old female who presented to the emergency room with left leg swelling. Workup with contrast-enhanced computed tomography revealed a left leg deep vein thrombosis with May-Thurner syndrome and a hematoma in the pelvic cavity without definite evidence of arterial bleeding. She was managed conservatively without surgical intervention, and also underwent inferior vena cava filter insertion and subsequent anticoagulation therapy for pulmonary thromboembolism. This case shows that SIVR can be successfully managed with close monitoring and conservative management, and anticoagulation may be safely applied despite the patient presenting with venous bleeding. PMID:26217647

  18. Short-lived Supershear Rupture

    NASA Astrophysics Data System (ADS)

    Fukuyama, E.; Xu, S.; Yamashita, F.; Mizoguchi, K.; Takizawa, S.; Kawakata, H.

    2015-12-01

    Fukuyama and Olsen (2002) computed the supershear rupture initiation, propagation and termination process due to a passage of high stress drop area (called asperity) using a boundary integral equation method. They found that supershear rupture continued to propagate after the passage through high stress drop area but it died after a certain propagation distance, which depends on the elastic energy released at the high stress drop area. Here, we could reproduce a similar phenomenon in the laboratory. We conducted large-scale biaxial friction experiments using a pair of meter-scaled metagabbro rock specimens (VP=6.9km/s, VS=3.6km/s) at the National Research institute for Earth Science and Disaster Prevention (NIED). We observed several stick slip rupture events that initiated close to an asperity and immediately became supershear ruptures. But after propagating certain distance they died out and co-existing subshear ruptures became prominent. If we look into details, during the supershear rupture, we could see a sequence of rupture acceleration, its short rest and re-acceleration. This feature reminds us of a sequential breakage of small high stress patches as predicted by Fukuyama and Madariaga (2000). These observations might be interpreted under a concept of energy balance where the energy transmission from strain energy released by the asperity to fracture energy consumed at the crack tip was not instantaneously balanced in space. This could be related to the fact that earthquake rupture velocity is rather smooth reported from the finite fault analysis of large earthquakes with seismic waveforms. References Fukuyama, E. and R. Madariaga (2000) Dynamic propagation and interaction of a rupture front on a planar fault, PAGEOPH, 257, 1959-1979. Fukuyama, E. and K.B. Olsen (2002) A condition for super-shear rupture propagation in a heterogeneous stress field, PAGEOPH, 159, 2047-2056.

  19. [Recurrence of a rudimentary uterine horn rupture at 25 weeks of gestation: a case report].

    PubMed

    Schmied, R; Sentilhes, L; Baron, M; Grzegorczyk, V; Resch, B; Marpeau, L

    2008-03-01

    Pregnancy in a rudimentary uterine horn is a rare event which can be revealed by uterine rupture. Following the fetal extraction, some authors recommend the ablation of the rudimentary horn, in order to limit the risk of uterine rupture in case of subsequent pregnancy in the same horn. We report the obstetrical outcome of a patient with a history of rudimentary uterine horn rupture the treatment of which was conservative. PMID:18308608

  20. Anonymous Communication Policies for the Internet: Results and Recommendations of the AAAS Conference.

    ERIC Educational Resources Information Center

    Teich, Al; Frankel, Mark S.; Kling, Rob; Lee, Yaching

    1999-01-01

    Reports the results of a conference on the Internet and anonymous communication organized by the American Association for the Advancement of Science (AAAS). Discusses how anonymous communications can be shaped by the law, education, and public awareness, and highlights the importance of involving all affected interests in policy development.…

  1. Left ventricular rupture postmitral valve replacement: Surviving a catastrophe

    PubMed Central

    Bisoyi, Samarjit; Mohanty, Jitendu; Mohapatra, Raghunath; Nayak, Debashish

    2015-01-01

    One of the dreaded mechanical complications of mitral valve replacement (MVR) is rupture of the left ventricle (LV). This report describes the early diagnosis and successful repair of rupture of posterior wall of LV in an elderly patient who underwent MVR. We have discussed the risk factors and perioperative issues implicated in such complication. The anesthesiologist as an intra-operative echocardiographer can aid in identifying the patient at risk. Though important surgical steps are necessary to prevent the complication; nonetheless, the anesthesiologist needs to take key measures in the perioperative period. PMID:25566717

  2. Ruptured aneurysms of sinuses of Valsalva

    PubMed Central

    Jugdutt, B. I.; Fraser, R. S.; Rossall, R. E.; Lee, S. J. K.

    1974-01-01

    At least one additional cardiac lesion was present in 18 consecutive patients with ruptured aneurysms of the sinuses of Valsalva who were investigated between 1956 and 1973 at the University of Alberta Hospital. Clinical diagnosis was made in 78% (14/18) of the patients. Confirmation at cardiac catheterization, operation or autopsy was obtained in all but one. The main sites of rupture were the right ventricle (seven cases), right atrium (five) and left ventricle (five). Fifty percent (9/18) are alive and well following prompt operative repair, an average of 8.2 years later (range, six months to 15 years). Replacement of the aortic valve was associated with a high mortality (50% early, 13% late, total 63%) which could be explained by the higher operative risk in this group of very ill patients. Eight patients (44.4%) had had bacterial endocarditis prior to presentation and this may have played a significant role in the rupture of the sinus of Valsalva aneurysm. ImagesFIG. 4FIG. 5 PMID:4278257

  3. Asymmetric processing of a substrate protein in sequential allosteric cycles of AAA+ nanomachines

    NASA Astrophysics Data System (ADS)

    Kravats, Andrea N.; Tonddast-Navaei, Sam; Bucher, Ryan J.; Stan, George

    2013-09-01

    Essential protein quality control includes mechanisms of substrate protein (SP) unfolding and translocation performed by powerful ring-shaped AAA+ (ATPases associated with various cellular activities) nanomachines. These SP remodeling actions are effected by mechanical forces imparted by AAA+ loops that protrude into the central channel. Sequential intra-ring allosteric motions, which underlie repetitive SP-loop interactions, have been proposed to comprise clockwise (CW), counterclockwise (CCW), or random (R) conformational transitions of individual AAA+ subunits. To probe the effect of these allosteric mechanisms on unfoldase and translocase functions, we perform Langevin dynamics simulations of a coarse-grained model of an all-alpha SP processed by the single-ring ClpY ATPase or by the double-ring p97 ATPase. We find that, in all three allosteric mechanisms, the SP undergoes conformational transitions along a common set of pathways, which reveals that the active work provided by the ClpY machine involves single loop-SP interactions. Nevertheless, the rates and yields of SP unfolding and translocation are controlled by mechanism-dependent loop-SP binding events, as illustrated by faster timescales of SP processing in CW allostery compared with CCW and R allostery. The distinct efficacy of allosteric mechanisms is due to the asymmetric collaboration of adjacent subunits, which involves CW-biased structural motions of AAA+ loops and results in CW-compatible torque applied onto the SP. Additional simulations of mutant ClpY rings, which render a subset of subunits catalytically-defective or reduce their SP binding affinity, reveal that subunit-based conformational transitions play the major role in SP remodeling. Based on these results we predict that the minimally functional AAA+ ring includes three active subunits, only two of which are adjacent.

  4. Achilles tendon rupture rehabilitation

    PubMed Central

    Kearney, R. S.; Parsons, N.; Underwood, M.; Costa, M. L.

    2015-01-01

    Objectives The evidence base to inform the management of Achilles tendon rupture is sparse. The objectives of this research were to establish what current practice is in the United Kingdom and explore clinicians’ views on proposed further research in this area. This study was registered with the ISRCTN (ISRCTN68273773) as part of a larger programme of research. Methods We report an online survey of current practice in the United Kingdom, approved by the British Orthopaedic Foot and Ankle Society and completed by 181 of its members. A total of ten of these respondents were invited for a subsequent one-to-one interview to explore clinician views on proposed further research in this area. Results The survey showed wide variations in practice, with patients being managed in plaster cast alone (13%), plaster cast followed by orthoses management (68%), and orthoses alone (19%). Within these categories, further variation existed regarding the individual rehabilitation facets, such as the length of time worn, the foot position within them and weight-bearing status. The subsequent interviews reflected this clinical uncertainty and the pressing need for definitive research. Conclusions The gap in evidence in this area has resulted in practice in the United Kingdom becoming varied and based on individual opinion. Future high-quality randomised trials on this subject are supported by the clinical community. Cite this article: Bone Joint Res 2015;4:65–9 PMID:25868938

  5. Sexual intercourse and cerebral aneurysmal rupture: potential mechanisms and precipitants.

    PubMed

    Reynolds, Matthew R; Willie, Jon T; Zipfel, Gregory J; Dacey, Ralph G

    2011-04-01

    Aneurysmal subarachnoid hemorrhage (SAH) is a significant cause of death in young and middle-aged individuals and causes tremendous morbidity in affected patients. Despite the identification of various risk factors, the series of events leading to the formation, growth, and rupture of intracranial aneurysms is poorly understood. Cerebral aneurysm rupture has been associated with sexual intercourse and other forms of physical exercise. In fact, multiple case series reported that coitus was the immediate preceding activity in 3.8-14.5% of patients suffering from aneurysmal SAH. This may be related to the large elevations in mean arterial blood pressure that occur in both males and females during sexual intercourse (130-175 and 125-160 mm Hg, respectively). While coitus and physical exercise share important physiological similarities, each may differentially affect the probability that a preformed aneurysm will rupture. In this literature review and synthesis, the authors analyze the physiological human response to sexual intercourse in an effort to delineate those factors that may precipitate aneurysmal rupture. The authors' analysis is based on the original data collected by Masters and Johnson. To the authors' knowledge, this is the first review to address the link between sexual intercourse and intracranial aneurysmal rupture. While actual measurements of the physiological variables relevant to SAH were not performed in this article, the authors make reasonable assumptions based on the available data to help elucidate the mechanism of sexually induced aneurysmal rupture. PMID:20540599

  6. [Ligament ruptures of the lower extremity in the elderly].

    PubMed

    Herbort, M; Raschke, M J

    2011-08-01

    There is an increasing incidence of ligament ruptures of the lower extremities in older patients. This higher incidence is caused by the typical current demographic changes in the population and the higher level of activity and athletic motivation of the older people in our society. In this review we address the most important ligament ruptures of the lower extremity in the old patient. Quadriceps tendon and Achilles tendon ruptures are mostly the result of degenerative and abrasion changes. The ACL rupture on the other hand occurs spontaneously after adequate trauma and without former degenerative changes especially in highly active patients. For a differentiated treatment of the older patient with tendon ruptures, secondary diseases, an increased risk and complication profile and a potentially decreased compliance during rehabilitation must be taken into consideration before indicating operative or conservative therapy. There are no strict age-related limitations for indication of an operative treatment of tendon ruptures in the older patient. In this patient group a differentiated treatment decision is recommended. PMID:21766204

  7. The ruptured PIP breast implant.

    PubMed

    Helyar, V; Burke, C; McWilliams, S

    2013-08-01

    Public concern erupted about the safety of Poly Implant Prothèse (PIP) breast implants when it was revealed in 2011 that they contained an inferior, unlicensed industrial-grade silicone associated with a high rate of rupture. There followed national guidance for UK clinicians, which led to a considerable increase in referrals of asymptomatic women for breast implant assessment. In this review we discuss possible approaches to screening the PIP cohort and the salient characteristics of a ruptured implant. PMID:23622796

  8. Earthquake rupture extents and coseismic slips promoted by damaged fault zones

    NASA Astrophysics Data System (ADS)

    Weng, Huihui; Yang, Hongfeng; Zhang, Zhenguo; Chen, Xiaofei

    2016-06-01

    Here we investigate the effects of damage fault zones on rupture propagation by conducting a series of 3-D dynamic rupture simulations on a planar vertical strike-slip fault. We find that damage fault zones can promote rupture extent and increase earthquake potency. The waves reflected from the bottom of shallow damage fault zones can increase shear stress on the fault and thus promote rupture propagation. In addition, the promotional effects increase with the width and depth extent of damage fault zones. The overall effects of the waves reflected from the fault-parallel side boundaries of damage fault zones are unfavorable for rupture propagation. Therefore, rupture propagation is promoted with the increased width of fault zones due to geometrical spreading effects. Moreover, nonground-breaking ruptures may reach the ground surface with the effects of damage fault zones. Furthermore, along-strike segmented fault zones as suggested by observations could also promote ruptures and may lead to preferred rupture directions if epicenters are close to fault zones. The effects of damage fault zones on rupture propagation hold important implications on assessing earthquake risk.

  9. Structural Basis of ATP Hydrolysis and Intersubunit Signaling in the AAA+ ATPase p97.

    PubMed

    Hänzelmann, Petra; Schindelin, Hermann

    2016-01-01

    p97 belongs to the superfamily of AAA+ ATPases and is characterized by a tandem AAA module, an N-terminal domain involved in substrate and cofactor interactions, and a functionally important unstructured C-terminal tail. The ATPase activity is controlled by an intradomain communication within the same protomer and an interdomain communication between neighboring protomers. Here, we present for the first time crystal structures in which the physiologically relevant p97 hexamer constitutes the content of the asymmetric unit, namely in the apo state without nucleotide in either the D1 or D2 module and in the pre-activated state with ATPγS bound to both modules. The structures provide new mechanistic insights into the interdomain communication mediated by conformational changes of the C terminus as well as an intersubunit signaling network, which couples the nucleotide state to the conformation of the central putative substrate binding pore. PMID:26712278

  10. A Statistical Comparison of the AAA Asteroids with the other Asteroid Populations

    NASA Astrophysics Data System (ADS)

    Kostolansky, E.

    1999-04-01

    In this paper a statistical comparison of the AAA (Apollo-Amor-Aten) asteroids with the other asteroid populations is presented and discussed. For the analysis the database of the osculating orbital elements (Epoch = 2451200.5) of the 47098 asteroids (February 1999) provided at the Lowell Observatory, Flagstaff, Arizona, U.S.A was used. Two kinds of distributions are presented: (1) The frequency distributions of the orbital elements e, i, omega, OMEGA and absolute magnitude H; (2) The distributions like a vs. e, H vs. i and H vs. r MIN, where r MIN is the minimum distance between the orbits of the Earth and an asteroid. The analysis was aimed to study some special features of the AAA asteroid population like its spatial distribution and size of tile asteroids in it and to compare them with the other groups of asteroids.

  11. Dosimetric comparison of Acuros XB, AAA, and XVMC in stereotactic body radiotherapy for lung cancer

    SciTech Connect

    Tsuruta, Yusuke; Nakata, Manabu; Higashimura, Kyoji; Nakamura, Mitsuhiro Matsuo, Yukinori; Monzen, Hajime; Mizowaki, Takashi; Hiraoka, Masahiro

    2014-08-15

    Purpose: To compare the dosimetric performance of Acuros XB (AXB), anisotropic analytical algorithm (AAA), and x-ray voxel Monte Carlo (XVMC) in heterogeneous phantoms and lung stereotactic body radiotherapy (SBRT) plans. Methods: Water- and lung-equivalent phantoms were combined to evaluate the percentage depth dose and dose profile. The radiation treatment machine Novalis (BrainLab AG, Feldkirchen, Germany) with an x-ray beam energy of 6 MV was used to calculate the doses in the composite phantom at a source-to-surface distance of 100 cm with a gantry angle of 0°. Subsequently, the clinical lung SBRT plans for the 26 consecutive patients were transferred from the iPlan (ver. 4.1; BrainLab AG) to the Eclipse treatment planning systems (ver. 11.0.3; Varian Medical Systems, Palo Alto, CA). The doses were then recalculated with AXB and AAA while maintaining the XVMC-calculated monitor units and beam arrangement. Then the dose-volumetric data obtained using the three different radiation dose calculation algorithms were compared. Results: The results from AXB and XVMC agreed with measurements within ±3.0% for the lung-equivalent phantom with a 6 × 6 cm{sup 2} field size, whereas AAA values were higher than measurements in the heterogeneous zone and near the boundary, with the greatest difference being 4.1%. AXB and XVMC agreed well with measurements in terms of the profile shape at the boundary of the heterogeneous zone. For the lung SBRT plans, AXB yielded lower values than XVMC in terms of the maximum doses of ITV and PTV; however, the differences were within ±3.0%. In addition to the dose-volumetric data, the dose distribution analysis showed that AXB yielded dose distribution calculations that were closer to those with XVMC than did AAA. Means ± standard deviation of the computation time was 221.6 ± 53.1 s (range, 124–358 s), 66.1 ± 16.0 s (range, 42–94 s), and 6.7 ± 1.1 s (range, 5–9 s) for XVMC, AXB, and AAA, respectively. Conclusions: In the

  12. Array Measurements of Earthquake Rupture.

    NASA Astrophysics Data System (ADS)

    Goldstein, Peter

    Accurate measurements of earthquake rupture are an essential step in the development of an understanding of the earthquake source process. In this dissertation new array analysis techniques are developed and used to make the first measurements of two-dimensional earthquake rupture propagation. In order to measure earthquake rupture successfully it is necessary to account for the nonstationary behavior of seismic waves and nonplanar wavefronts due to time delays caused by local heterogeneities. Short time windows are also important because they determine the precision with which it is possible to measure rupture times of earthquake sources. The subarray spatial averaging and seismogram alignment methods were developed for these reasons. The basic algorithm which is used to compute frequency-wavenumber power spectra is the multiple signal characterization (MUSIC) method. Although a variety of methods could be applied with subarray spatial averaging and seismogram alignment, MUSIC is used because it has better resolution of multiple sources than other currently available methods and it provides a unique solution. Power spectra observed at the array are converted into source locations on the fault plane by tracing rays through a layered medium. A dipping layer correction factor is introduced to account for a laterally varying basin structure such as that found beneath the SMART 1 array in Taiwan. A framework is presented that allows for the estimation of precision and resolution of array measurements of source locations and can be used to design an optimum array for a given source. These methods are used to show that the November 14th 1986, M_{L} = 7.0 Hualien, Taiwan earthquake began as a shallow event with unilateral rupture from southwest to northeast. A few seconds later a second, deeper and larger event began rupturing from below the hypocentral region from southwest to northeast slightly down-dip. Energy density estimates indicate larger energy sources at greater

  13. Rupture of the tracheobronchial tree.

    PubMed Central

    Roxburgh, J C

    1987-01-01

    Eleven cases of tracheobronchial rupture are described. Nine were the result of external non-penetrating trauma and all but three had other serious injuries. The remaining two were caused by endobronchial intubation. Of the cases caused by external injury, respiratory tract injury was confined to the cervical trachea in three. Two required tracheostomy and repair and the third was managed conservatively; all made satisfactory recoveries. Intrathoracic rupture was recognised on or soon after admission in three cases. One patient died of uncontrollable pulmonary haemorrhage before he could be operated on; immediate repair gave good long term results in the other two. In three cases rupture of the main bronchus was not recognised until complete obstruction developed three, five, and 12 weeks after the accidents. The strictures were resected and the lung re-expanded. Robertshaw endobronchial tubes ruptured the left main bronchus in two patients undergoing oesophageal surgery. Uneventful recovery followed immediate repair. The difficulty of confirming rupture of a major airway is discussed and the importance of conserving the lung when the diagnosis has been missed is emphasised. Images PMID:3317977

  14. Transcatheter closure of ruptured sinus Valsalva aneurysm with retrograde approach.

    PubMed

    Narin, Nazmi; Ozyurt, Abdullah; Baykan, Ali; Uzüm, Kazım

    2014-04-01

    A three-year-old girl with multiple heart malformations admitted to the pediatric cardiology unit because of excessive sweating and fatigue. Abnormal color Doppler flow was detected into the right atrium from the dilated coronary sinus on the echocardiographic examination, and ruptured sinus Valsalva aneurysm (SVA) was diagnosed. Although in most such cases, an antegrade transcatheter approach has been used, a retrograde approach can be used as a cost-effective treatment modality in those cases with selective high-risk surgery. In this report, we present a patient with ruptured SVA, which was closed via Amplatzer vascular plug-4 by retrograde approach. PMID:24769826

  15. Spontaneous Liver Rupture After Treatment With Drug-Eluting Beads

    SciTech Connect

    Ritter, C. O.; Wartenberg, M.; Mottok, A.; Steger, U.; Goltz, J. P.; Hahn, D.; Kickuth, R.

    2012-02-15

    Spontaneous rupture of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) is a rare and life-threatening complication. Pathophysiologic mechanisms are not yet fully known; it is suggested that rupture is preceded by reactive tissue edema and intratumerous bleeding, leading to a rapid expansion of tumour mass with risk of extrahepatic bleeding in the case of subcapsular localisation. This case report discusses a sudden, unexpected lethal complication in a 74 year-old male patient treated with TACE using DC Bead loaded with doxorubicin (DEBDOX) in a progressive multifocal HCC.

  16. Mechanochemical basis of protein degradation by a double-ring AAA+ machine.

    PubMed

    Olivares, Adrian O; Nager, Andrew R; Iosefson, Ohad; Sauer, Robert T; Baker, Tania A

    2014-10-01

    Molecular machines containing double or single AAA+ rings power energy-dependent protein degradation and other critical cellular processes, including disaggregation and remodeling of macromolecular complexes. How the mechanical activities of double-ring and single-ring AAA+ enzymes differ is unknown. Using single-molecule optical trapping, we determine how the double-ring ClpA enzyme from Escherichia coli, in complex with the ClpP peptidase, mechanically degrades proteins. We demonstrate that ClpA unfolds some protein substrates substantially faster than does the single-ring ClpX enzyme, which also degrades substrates in collaboration with ClpP. We find that ClpA is a slower polypeptide translocase and that it moves in physical steps that are smaller and more regular than steps taken by ClpX. These direct measurements of protein unfolding and translocation define the core mechanochemical behavior of a double-ring AAA+ machine and provide insight into the degradation of proteins that unfold via metastable intermediates. PMID:25195048

  17. Assaying the kinetics of protein denaturation catalyzed by AAA+ unfolding machines and proteases.

    PubMed

    Baytshtok, Vladimir; Baker, Tania A; Sauer, Robert T

    2015-04-28

    ATP-dependent molecular machines of the AAA+ superfamily unfold or remodel proteins in all cells. For example, AAA+ ClpX and ClpA hexamers collaborate with the self-compartmentalized ClpP peptidase to unfold and degrade specific proteins in bacteria and some eukaryotic organelles. Although degradation assays are straightforward, robust methods to assay the kinetics of enzyme-catalyzed protein unfolding in the absence of proteolysis have been lacking. Here, we describe a FRET-based assay in which enzymatic unfolding converts a mixture of donor-labeled and acceptor-labeled homodimers into heterodimers. In this assay, ClpX is a more efficient protein-unfolding machine than ClpA both kinetically and in terms of ATP consumed. However, ClpP enhances the mechanical activities of ClpA substantially, and ClpAP degrades the dimeric substrate faster than ClpXP. When ClpXP or ClpAP engage the dimeric subunit, one subunit is actively unfolded and degraded, whereas the other subunit is passively unfolded by loss of its partner and released. This assay should be broadly applicable for studying the mechanisms of AAA+ proteases and remodeling chaperones. PMID:25870262

  18. Characterization of ATPase activity of the AAA ARC from Bifidobacterium longum subsp. infantis.

    PubMed

    Guzmán-Rodríguez, Mabel; de la Rosa, Ana Paulina Barba; Santos, Leticia

    2015-01-01

    Bifidobacteria are considered to be probiotics that exist in the large intestine and are helpful to maintain human health. Oral administration of bifidobacteria may be effective in improving the intestinal flora and environment, stimulating the immune response and possibly preventing cancer. However, for consistent and positive results, further well-controlled studies are urgently needed to describe the basic mechanisms of this microorganism. Analysis of the proteasome-lacking Bifidobacterium longum genome reveals that it possesses a gene, IPR003593 AAA ATPase core, which codes a 56 kDa protein containing one AAA ATPase domain. Phylogenetic classification made by CLANS, positioned this sequence into the ARC divergent branch of the AAA ATPase family of proteins. N-terminal analysis of the sequence indicates this protein is closely related to other ATPases such as the Rhodococcus erythropolis ARC, Archaeoglobus fulgidus PAN, Mycobacterium tuberculosis Mpa and the human proteasomal Rpt1 subunit. This gene was cloned, the full-length recombinant protein was overexpressed in Escherichia coli, purified as a high-molecular size complex and named Bl-ARC. Enzymatic characterization showed that Bl-ARC ATPase is active, Mg(+2)-dependent and sensitive to N-ethylmaleimide. Gene organization positions bl-arc in a region flanked by a cluster of genes that includes pup, dop and pafA genes. These findings point to a possible function as a chaperone in the degradation pathway via pupylation. PMID:26015994

  19. Structural Insights into the Allosteric Operation of the Lon AAA+ Protease.

    PubMed

    Lin, Chien-Chu; Su, Shih-Chieh; Su, Ming-Yuan; Liang, Pi-Hui; Feng, Chia-Cheng; Wu, Shih-Hsiung; Chang, Chung-I

    2016-05-01

    The Lon AAA+ protease (LonA) is an evolutionarily conserved protease that couples the ATPase cycle into motion to drive substrate translocation and degradation. A hallmark feature shared by AAA+ proteases is the stimulation of ATPase activity by substrates. Here we report the structure of LonA bound to three ADPs, revealing the first AAA+ protease assembly where the six protomers are arranged alternately in nucleotide-free and bound states. Nucleotide binding induces large coordinated movements of conserved pore loops from two pairs of three non-adjacent protomers and shuttling of the proteolytic groove between the ATPase site and a previously unknown Arg paddle. Structural and biochemical evidence supports the roles of the substrate-bound proteolytic groove in allosteric stimulation of ATPase activity and the conserved Arg paddle in driving substrate degradation. Altogether, this work provides a molecular framework for understanding how ATP-dependent chemomechanical movements drive allosteric processes for substrate degradation in a major protein-destruction machine. PMID:27041592

  20. Subunit dynamics and nucleotide-dependent asymmetry of an AAA(+) transcription complex.

    PubMed

    Zhang, Nan; Gordiyenko, Yuliya; Joly, Nicolas; Lawton, Edward; Robinson, Carol V; Buck, Martin

    2014-01-01

    Bacterial enhancer binding proteins (bEBPs) are transcription activators that belong to the AAA(+) protein family. They form higher-order self-assemblies to regulate transcription initiation at stress response and pathogenic promoters. The precise mechanism by which these ATPases utilize ATP binding and hydrolysis energy to remodel their substrates remains unclear. Here we employed mass spectrometry of intact complexes to investigate subunit dynamics and nucleotide occupancy of the AAA(+) domain of one well-studied bEBP in complex with its substrate, the σ(54) subunit of RNA polymerase. Our results demonstrate that the free AAA(+) domain undergoes significant changes in oligomeric states and nucleotide occupancy upon σ(54) binding. Such changes likely correlate with one transition state of ATP and are associated with an open spiral ring formation that is vital for asymmetric subunit function and interface communication. We confirmed that the asymmetric subunit functionality persists for open promoter complex formation using single-chain forms of bEBP lacking the full complement of intact ATP hydrolysis sites. Outcomes reconcile low- and high-resolution structures and yield a partial sequential ATP hydrolysis model for bEBPs. PMID:24055699

  1. Functional characterization of fidgetin, an AAA-family protein mutated in fidget mice

    SciTech Connect

    Yang Yan; Mahaffey, Connie L.; Berube, Nathalie; Nystuen, Arne; Frankel, Wayne N. . E-mail: wnf@jax.org

    2005-03-10

    The mouse fidget mutation is an autosomal recessive mutation that renders reduced or absent semicircular canals, microphthalmia, and various skeletal abnormalities to affected mice. We previously identified the defective gene which encodes fidgetin, a new member of the ATPases associated with diverse cellular activities (AAA proteins). Here, we report on the subcellular localization of fidgetin as well as that of two closely related proteins, fidgetin-like 1 and fidgetin-like 2. Epitope-tagging and immunostaining revealed that both fidgetin and fidgetin-like 2 were predominantly localized to the nucleus, whereas fidgetin-like 1 was both nuclear and cytoplasmic. Furthermore, deletion studies identified a putative bipartite nuclear localization signal in the middle portion of the fidgetin protein. Since AAA proteins are known to form functional hetero- or homo-hexamers, we used reciprocal immunoprecipitation to examine the potential interaction among these proteins. We found that fidgetin interacted with itself and this specific interaction was abolished when either the N- or C-terminus of the protein was truncated. Taken together, our results suggest that fidgetin is a nuclear AAA-family protein with the potential to form homo-oligomers, thus representing the first step towards the elucidation of fidgetin's cellular function and the disease mechanism in fidget mutant mice.

  2. Hypolipidaemic and antioxidant effects of fruits of Musa AAA (Chenkadali) in alloxan induced diabetic rats.

    PubMed

    Kaimal, Smitha; Sujatha, K S; George, Sisilamma

    2010-02-01

    Hypolipidaemic and antioxidant effects of ethanol extract of mature green fruits of Musa AAA (Chenkadali) was evaluated in alloxan induced diabetic rats. The effect of extract at two doses, 500 mg/kg body weight and 1000 mg/kg body weight was analysed and compared with a standard drug, glibenclamide. Rats administered with alloxan showed significantly increased levels of serum triacylglycerol, total cholesterol and alanine amino transferase (ALT) activity. Lipid peroxides increased significantly while reduced glutathione (GSH) decreased considerably in liver and pancreas. Oral administration of the ethanol extract of fruits of Musa AAA (Chenkadali) significantly decreased the levels of serum triacylglycerol, cholesterol and ALT activity. Significant decrease was also observed in the level of lipid peroxides while GSH content increased substantially in liver and pancreas. The effect was dose independent and rats treated with 500 mg/kg body weight showed comparable levels of serum triacylglycerol, cholesterol, ALT activity and liver lipid peroxides to that of normal control and glibenclamide treated groups. Although, there was no significant difference, treatment with 500 mg/kg body weight of the extract showed a higher content of GSH and lower level of lipid peroxides in pancreas compared with glibenclamide. Histopathological examination of pancreas and liver revealed regeneration of islet cells and hepatocytes respectively, which correlate with the biochemical findings. The present study shows that ethanol extract of mature green fruits of Musa AAA (Chenkadali) has antioxidant and hypolipidaemic properties and may be used for treating diabetes mellitus. PMID:20455326

  3. Molecular snapshots of the Pex1/6 AAA+ complex in action

    PubMed Central

    Ciniawsky, Susanne; Grimm, Immanuel; Saffian, Delia; Girzalsky, Wolfgang; Erdmann, Ralf; Wendler, Petra

    2015-01-01

    The peroxisomal proteins Pex1 and Pex6 form a heterohexameric type II AAA+ ATPase complex, which fuels essential protein transport across peroxisomal membranes. Mutations in either ATPase in humans can lead to severe peroxisomal disorders and early death. We present an extensive structural and biochemical analysis of the yeast Pex1/6 complex. The heterohexamer forms a trimer of Pex1/6 dimers with a triangular geometry that is atypical for AAA+ complexes. While the C-terminal nucleotide-binding domains (D2) of Pex6 constitute the main ATPase activity of the complex, both D2 harbour essential substrate-binding motifs. ATP hydrolysis results in a pumping motion of the complex, suggesting that Pex1/6 function involves substrate translocation through its central channel. Mutation of the Walker B motif in one D2 domain leads to ATP hydrolysis in the neighbouring domain, giving structural insights into inter-domain communication of these unique heterohexameric AAA+ assemblies. PMID:26066397

  4. An atypical AAA+ ATPase assembly controls efficient transposition through DNA remodeling and transposase recruitment

    PubMed Central

    Arias-Palomo, Ernesto; Berger, James M.

    2015-01-01

    Transposons are ubiquitous genetic elements that drive genome rearrangements, evolution, and the spread of infectious disease and drug-resistance. Many transposons, such as Mu, Tn7 and IS21, require regulatory AAA+ ATPases for function. We use x-ray crystallography and cryo-electron microscopy to show that the ATPase subunit of IS21, IstB, assembles into a clamshell-shaped decamer that sandwiches DNA between two helical pentamers of ATP-associated AAA+ domains, sharply bending the duplex into a 180° U-turn. Biochemical studies corroborate key features of the structure, and further show that the IS21 transposase, IstA, recognizes the IstB•DNA complex and promotes its disassembly by stimulating ATP hydrolysis. Collectively, these studies reveal a distinct manner of higher-order assembly and client engagement by a AAA+ ATPase and suggest a mechanistic model where IstB binding and subsequent DNA bending primes a selected insertion site for efficient transposition. PMID:26276634

  5. Complicated malaria and a covert ruptured spleen: a case report.

    PubMed

    Waweru, Peter; Macleod, Jana; Gikonyo, Anthony

    2014-01-01

    Spontaneous splenic rupture in complicated malaria is an uncommon cause of hemoperitoneum in the tropics. The exact incidence of splenic rupture is unknown, largely due to under-reporting, but has been estimated at ∼2%. Its pathophysiology is linked to the formation of a subcapsular hematoma. Upon rupture, patients present with features of shock and peritonitis and in most cases (95%), computed tomography (CT) scan detects the splenic injury. Patients should be managed conservatively with splenectomy reserved for patients with shock and hemoperitoneum due to risk of post-splenectomy sepsis. We report the case of a 38-year-old man with severe malaria who presented with fever, chills and abdominal pains. A CT scan abdomen failed to reveal splenic parenchymal injury or any splenic extravasation of contrast. Conservative management was unsuccessful. Exploratory laparatomy confirmed the spleen as the site of bleeding necessitating a splenectomy. PMID:25395608

  6. Treatment of Ruptured Vertebral Artery Dissecting Aneurysms

    PubMed Central

    Hamasaki, Osamu; Ikawa, Fusao; Hidaka, Toshikazu; Kurokawa, Yasuharu; Yonezawa, Ushio

    2014-01-01

    Summary We evaluated the outcomes of endovascular or surgical treatment of ruptured vertebral artery dissecting aneurysms (VADAs), and investigated the relations between treatment complications and the development and location of the posterior inferior cerebellar artery (PICA). We treated 14 patients (12 men, two women; mean age, 56.2 years) with ruptured VADAs between March 1999 and June 2012 at our hospital. Six and eight patients had Hunt and Hess grades 1-3 and 4-5, respectively. Twelve patients underwent internal endovascular trapping, one underwent proximal endovascular occlusion alone, and one underwent proximal endovascular occlusion in the acute stage and occipital artery (OA)-PICA anastomosis and surgical trapping in the chronic stage. The types of VADA based on their location relative to the ipsilateral PICA were distal, PICA-involved, and non-PICA in nine, two, and three patients, respectively. The types of PICA based on their development and location were bilateral anterior inferior cerebellar artery (AICA)-PICA, ipsilateral AICA-PICA, extradural, and intradural type in one, two, two, and nine patients, respectively. Two patients with high anatomical risk developed medullary infarction, but their midterm outcomes were better than in previous reports. The modified Rankin scale indicated grades 0-2, 3-5, and 6 in eight, three, and three patients, respectively. A good outcome is often obtained in the treatment of ruptured VADA using internal endovascular trapping, except in the PICA-involved type, even with high-grade subarachnoid hemorrhage. Treatment of the PICA-involved type is controversial. The anatomical location and development of PICA may be predicted by complications with postoperative medullary infarction. PMID:24976093

  7. Structural Insights into the Unusually Strong ATPase Activity of the AAA Domain of the Caenorhabditis elegans Fidgetin-like 1 (FIGL-1) Protein*

    PubMed Central

    Peng, Wentao; Lin, Zhijie; Li, Weirong; Lu, Jing; Shen, Yuequan; Wang, Chunguang

    2013-01-01

    The FIGL-1 (fidgetin like-1) protein is a homolog of fidgetin, a protein whose mutation leads to multiple developmental defects. The FIGL-1 protein contains an AAA (ATPase associated with various activities) domain and belongs to the AAA superfamily. However, the biological functions and developmental implications of this protein remain unknown. Here, we show that the AAA domain of the Caenorhabditis elegans FIGL-1 protein (CeFIGL-1-AAA), in clear contrast to homologous AAA domains, has an unusually high ATPase activity and forms a hexamer in solution. By determining the crystal structure of CeFIGL-1-AAA, we found that the loop linking helices α9 and α10 folds into the short helix α9a, which has an acidic surface and interacts with a positively charged surface of the neighboring subunit. Disruption of this charge interaction by mutagenesis diminishes both the ATPase activity and oligomerization capacity of the protein. Interestingly, the acidic residues in helix α9a of CeFIGL-1-AAA are not conserved in other homologous AAA domains that have relatively low ATPase activities. These results demonstrate that the sequence of CeFIGL-1-AAA has adapted to establish an intersubunit charge interaction, which contributes to its strong oligomerization and ATPase activity. These unique properties of CeFIGL-1-AAA distinguish it from other homologous proteins, suggesting that CeFIGL-1 may have a distinct biological function. PMID:23979136

  8. Vortex dynamics in ruptured and unruptured intracranial aneurysms

    NASA Astrophysics Data System (ADS)

    Trylesinski, Gabriel

    Intracranial aneurysms (IAs) are a potentially devastating pathological dilation of brain arteries that affect 1.5-5 % of the population. Causing around 500 000 deaths per year worldwide, their detection and treatment to prevent rupture is critical. Multiple recent studies have tried to find a hemodynamics predictor of aneurysm rupture, but concluded with distinct opposite trends using Wall Shear Stress (WSS) based parameters in different clinical datasets. Nevertheless, several research groups tend to converge for now on the fact that the flow patterns and flow dynamics of the ruptured aneurysms are complex and unstable. Following this idea, we investigated the vortex properties of both unruptured and ruptured cerebral aneurysms. A brief comparison of two Eulerian vortex visualization methods (Q-criterion and lambda 2 method) showed that these approaches gave similar results in our complex aneurysm geometries. We were then able to apply either one of them to a large dataset of 74 patient specific cases of intracranial aneurysms. Those real cases were obtained by 3D angiography, numerical reconstruction of the geometry, and then pulsatile CFD simulation before post-processing with the mentioned vortex visualization tools. First we tested the two Eulerian methods on a few cases to verify their implementation we made as well as compare them with each other. After that, the Q-criterion was selected as method of choice for its more obvious physical meaning (it shows the balance between two characteristics of the flow, its swirling and deformation). Using iso-surfaces of Q, we started by categorizing the patient-specific aneurysms based on the gross topology of the aneurysmal vortices. This approach being unfruitful, we found a new vortex-based characteristic property of ruptured aneurysms to stratify the rupture risk of IAs that we called the Wall-Kissing Vortices, or WKV. We observed that most ruptured aneurysms had a large amount of WKV, which appears to agree with

  9. Endovascular vs. Open Repair for Ruptured Abdominal Aortic Aneurysm

    PubMed Central

    Patelis, Nikolaos; Moris, Demetrios; Karaolanis, Georgios; Georgopoulos, Sotiris

    2016-01-01

    Background Patients presenting with ruptured abdominal aortic aneurysms are most often treated with open repair despite the fact that endovascular aneurysm repair is a less invasive and widely accepted method with clear benefits for elective aortic aneurysm patients. A debate exists regarding the definitive benefit in endovascular repair for patients with a ruptured abdominal aortic aneurysm. The aim of this literature review was to determine if any trends exist in favor of either open or endovascular repair. Material/Methods A literature search was performed using PUBMED, OVID, and Google Scholar databases. The search yielded 64 publications. Results Out of 64 publications, 25 were retrospective studies, 12 were population-based, 21 were prospective, 5 were the results of RCTs, and 1 was a case-series. Sixty-one studies reported on early mortality and provided data comparing endovascular repair (rEVAR) and open repair (rOR) for ruptured abdominal aneurysm groups. Twenty-nine of these studies reported that rEVAR has a lower early mortality rate. Late mortality after rEVAR compared to that of rOR was reported in 21 studies for a period of 3 to 60 months. Results of 61.9% of the studies found no difference in late mortality rates between these 2 groups. Thirty-nine publications reported on the incidence of complications. Approximately half of these publications support that the rEVAR group has a lower complication rate and the other half found no difference between the groups. Length of hospital stay has been reported to be shorter for rEVAR in most studies. Blood loss and need for transfusion of either red cells or fresh frozen plasma was consistently lower in the rEVAR group. Conclusions Differences between the included publications affect the outcomes. Randomized control trials have not been able to provide clear conclusions. rEVAR can now be considered a safe method of treating rAAA, and is at least equal to the well-established rOR method. PMID:27090791

  10. Rupture interaction with fault jogs

    NASA Astrophysics Data System (ADS)

    Sibson, Richard H.

    Propagation of moderate to large earthquake ruptures within major transcurrent fault systems is affected by their large-scale brittle infrastructure, comprising echelon segmentation and curvature of principal slip surfaces (PSS) within typically ˜1 km wide main fault zones. These PSS irregularities are classified into dilational and antidilational fault jogs depending on the tendency for areal increase or reduction, respectively, across the jog structures. High precision microearthquake studies show that the jogs often extend throughout the seismogenic regime to depths of around 10 km. On geomorphic evidence, the larger jogs may persist for periods >105 years. While antidilational jogs form obstacles to both short- and long-term displacements, dilational jogs appear to act as kinetic barriers capable of perturbing or arresting earthquake ruptures, but allowing time-dependent slip transfer. In the case of antidilational jogs slip transfer is accommodated by widespread subsidiary faulting, but for dilational jogs it additionally involves extensional fracture opening localized in the echelon stepover. In fluid-saturated crust, the rapid opening of linking extensional fracture systems to allow passage of earthquake ruptures is opposed by induced suctions which scale with the width of the jog. Rupture arrest at dilational jogs may then be followed by delayed slip transfer as fluid pressures reequilibrate by diffusion. Aftershock distributions associated with the different fault jogs reflect these contrasts in their internal structure and mechanical response.

  11. Quadriceps Tendon Rupture due to Postepileptic Convulsion

    PubMed Central

    Erkut, Adem; Guvercin, Yilmaz; Sahin, Rifat; Keskin, Davut

    2014-01-01

    We present a case of quadriceps tendon (QT) rupture. QT ruptures can occur in all ages. The cause is mostly traumatic in origin. Spontaneous ruptures that are thought to result from predisposing conditions are rare. Post-convulsion QT ruptures lacking traumas in their history can be overlooked in clinical examinations. This should be born in mind by the attending physician, as early diagnosis and treatment of the condition can lead to satisfactory outcomes. PMID:24944977

  12. Mechanics of Multifault Earthquake Ruptures

    NASA Astrophysics Data System (ADS)

    Fletcher, J. M.; Oskin, M. E.; Teran, O.

    2015-12-01

    The 2010 El Mayor-Cucapah earthquake of magnitude Mw 7.2 produced the most complex rupture ever documented on the Pacific-North American plate margin, and the network of high- and low-angle faults activated in the event record systematic changes in kinematics with fault orientation. Individual faults have a broad and continuous spectrum of slip sense ranging from endmember dextral strike slip to normal slip, and even faults with thrust sense of dip slip were commonly observed in the aftershock sequence. Patterns of coseismic slip are consistent with three-dimensional constrictional strain and show that integrated transtensional shearing can be accommodated in a single earthquake. Stress inversions of coseismic surface rupture and aftershock focal mechanisms define two coaxial, but permuted stress states. The maximum (σ1) and intermediate (σ2) principal stresses are close in magnitude, but flip orientations due to topography- and density-controlled gradients in lithostatic load along the length of the rupture. Although most large earthquakes throughout the world activate slip on multiple faults, the mechanical conditions of their genesis remain poorly understood. Our work attempts to answer several key questions. 1) Why do complex fault systems exist? They must do something that simple, optimally-oriented fault systems cannot because the two types of faults are commonly located in close proximity. 2) How are faults with diverse orientations and slip senses prepared throughout the interseismic period to fail spontaneously together in a single earthquake? 3) Can a single stress state produce multi-fault failure? 4) Are variations in pore pressure, friction and cohesion required to produce simultaneous rupture? 5) How is the fabric of surface rupture affected by variations in orientation, kinematics, total geologic slip and fault zone architecture?

  13. 46 CFR 64.61 - Rupture disc.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Rupture disc. 64.61 Section 64.61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.61 Rupture disc. If a rupture...

  14. 46 CFR 64.61 - Rupture disc.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Rupture disc. 64.61 Section 64.61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.61 Rupture disc. If a rupture...

  15. 46 CFR 64.61 - Rupture disc.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Rupture disc. 64.61 Section 64.61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.61 Rupture disc. If a rupture...

  16. 46 CFR 64.61 - Rupture disc.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Rupture disc. 64.61 Section 64.61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.61 Rupture disc. If a rupture...

  17. 46 CFR 64.61 - Rupture disc.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Rupture disc. 64.61 Section 64.61 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.61 Rupture disc. If a rupture...

  18. [Proximal and distal ruptures of the biceps brachii tendon].

    PubMed

    Klonz, A; Loitz, D; Reilmann, H

    2003-09-01

    Proximal ruptures. Ruptures of the long head of the M. biceps humeri are commonly caused by degenerative changes within the tendon. Non-operative treatment gives good results, the loss of power regarding elbow flexion and supination amounts to only 8-21%. Refixation may be indicated for cosmetic reasons and offers a small but evident improvement of flexion and supination power. Deformity of the slipped muscle can be corrected effectively. Residual complaints after conservative treatment often result from associated subacromial problems. Distal ruptures. Ruptures of the distal tendon should be treated operatively. The loss of power after conservative treatment is evident (30-40% for flexion, >50% for supination). Extra-anatomical tenodesis to the brachialis muscle or anatomical fixation to the radial tuberosity can be applied. Flexion power and cosmesis can be addressed by both techniques. If supination strength is to be restored, the tendon has to be fixed anatomically. Preparation of the tuberosity bears the risk of heterotopic ossification or nerve damage. Mini-open techniques, using only a limited anterior approach, may decrease risks. PMID:14959750

  19. [Uterine rupture. A case of spontaneous rupture in a thirty week primiparous gestation ].

    PubMed

    Bretones, S; Cousin, C; Gualandi, M; Mellier, G

    1997-01-01

    Uterine rupture is one of the major complications of pregnancy. Most spontaneous uterine ruptures occur during labor in parturients with a scarred uterus. Spontaneous rupture where the uterus is unscarred are more rare and occur more frequently in older multiparous patients. Starting from a case of uterine rupture occurring in a 40 year-old primiparous women, we will present a review of the literature concerning cases of rupture in healthy uteri with no obvious cause. PMID:9265057

  20. NASA Astrophysics E/PO Impact: NASA SOFIA AAA Program Evaluation Results

    NASA Astrophysics Data System (ADS)

    Harman, Pamela; Backman, Dana E.; Clark, Coral; Inverness Research Sofia Aaa Evaluation Team, Wested Sofia Aaa Evaluation Team

    2015-01-01

    SOFIA is an airborne observatory, studying the universe at infrared wavelengths, capable of making observations that are impossible for even the largest and highest ground-based telescopes. SOFIA also inspires the development of new scientific instrumentation and fosters the education of young scientists and engineers.SOFIA is an 80% - 20% partnership of NASA and the German Aerospace Center (DLR), consisting of an extensively modified Boeing 747SP aircraft carrying a reflecting telescope with an effective diameter of 2.5 meters (100 inches). The SOFIA aircraft is based at NASA Armstrong Flight Research Center, Building 703, in Palmdale, California. The Science Program and Outreach Offices are located at NASA Ames Research center. SOFIA is a program in NASA's Science Mission Directorate, Astrophysics Division.Data will be collected to study many different kinds of astronomical objects and phenomena, including star cycles, solar system formation, identification of complex molecules in space, our solar system, galactic dust, nebulae and ecosystems.Airborne Astronomy Ambassador (AAA) Program:The SOFIA Education and Communications program exploits the unique attributes of airborne astronomy to contribute to national goals for the reform of science, technology, engineering, and math (STEM) education, and to elevate public scientific and technical literacy.The AAA effort is a professional development program aspiring to improve teaching, inspire students, and inform the community. To date, 55 educators from 21 states; Cycles 0, 1 and 2; have completed their astronomy professional development and their SOFIA science flight experience. Evaluation has confirmed the program's positive impact on the teacher participants, on their students, and in their communities. The inspirational experience has positively impacted their practice and career trajectory. AAAs have incorporated content knowledge and specific components of their experience into their curricula, and have given

  1. SU-E-P-16: A Feasibility Study of Using Eclipse AAA for SRS Treatement

    SciTech Connect

    Lim, S; LoSasso, T

    2015-06-15

    Purpose: To commission Varian Eclipse AAA for SRS treatment and compare the accuracy with Brainlab iPlan system for clinical cases measured with radiochromic film. Methods: A 6MV AAA clinical model for a Varian TrueBeam STx is used as baseline. The focal spot and field size of the baseline model(BASE) are (1.75,0.75) and 40×40cm{sup 2} respectively. Maximum field sizes, output factors(S{sub t}), FWHM focal spot and secondary source sizes are systematically adjusted to obtain an optimized model(OPT) by comparing the calculated PDD’s, profiles, and output factors with measurements taken with a stereotactic diode(SD) and, cc01 and cc04 ion chambers in Blue Phantom. In-phantom dose distributions of clinical SRS fields are calculated using the OPT and the clinical Brainlab iPlan pencil-beam. Within the 90% isodose-line(ROI), the average dose difference between the calculations and radiochromic film measurements are assessed. Results: The maximum field, focal spot and secondary source sizes for the OPT are 15×15cm{sup 2}, (0,0), and 32.3mm respectively. The OPT St input at 1.0 and 2.0cm fields are increased by 4.5% and 1.5% from BASE. The calculated output of the BASE and OPT underestimate by 16.1%–3.2% respectively at 0.5×0.5cm{sup 2} field and 3.1%−0.02% respectively at 1.0×1.0cm{sup 2} field. The depth doses at 10cm are within 3.5% and 0.4% of measurements for 0.5×0.5 and 1.0×1.0cm{sup 2}. The ROI dose of OPT and iPlan are within 1.6% and 0.6% of film measurements for 3.0cm clinical fields. For 1.0cm fields, the ROI dose of OPT underestimate 0.0–2.0% and iPlan overestimates 1.7–2.9% relative to measurements. Conclusion: The small field dose calculation of Eclipse AAA algorithm can be significantly improved by carefully adjusting the input parameters. The larger deviation of the OPT for 0.5×0.5cm{sup 2} field from measurements can be attributed to the lowest 1.0cm field size input limit of AAA. The OPT compares reasonably well with the iPlan pencil

  2. Pathological findings of saccular cerebral aneurysms-impact of subintimal fibrin deposition on aneurysm rupture.

    PubMed

    Hokari, Masaaki; Nakayama, Naoki; Nishihara, Hiroshi; Houkin, Kiyohiro

    2015-07-01

    Although several studies have suggested that aneurysmal wall inflammation and laminar thrombus are associated with the rupture of saccular aneurysms, the mechanisms leading to the rupture remain obscure. We performed full exposure of aneurysms before clip application and attempted to keep the fibrin cap on the rupture point. Using these specimens in a nearly original state before surgery, we conducted a pathological analysis and studied the differences between ruptured and unruptured aneurysms to clarify the mechanism of aneurysmal wall degeneration. This study included ruptured (n = 28) and unruptured (n = 12) saccular aneurysms resected after clipping. All of the ruptured aneurysms were obtained within 24 h of onset. Immunostainings for markers of inflammatory cells (CD68) and classical histological staining techniques were performed. Clinical variables and pathological findings from ruptured and unruptured aneurysms were compared. Patients with ruptured or unruptured aneurysms did not differ by age, gender, size, location, and risk factors, such as hypertension, smoking, and hyperlipidemia. The absence or fragmentation of the internal elastica lamina, the myointimal hyperplasia, and the thinning of the aneurysmal wall were generally observed in both aneurysms. The existence of subintimal fibrin deposition, organized laminar thrombus, intramural hemorrhage, neovascularization, and monocyte infiltration are more frequently observed in ruptured aneurysms. Multivariate logistic regression analysis showed that ruptured aneurysm was associated with presence of subintimal fibrin deposition and monocyte infiltration. These findings suggest that subintimal fibrin deposition and chronic inflammation have a strong impact on degeneration of the aneurysmal wall leading to their rupture, and this finding may be caused by endothelial dysfunction. PMID:25860660

  3. Predicting the endpoints of earthquake ruptures.

    PubMed

    Wesnousky, Steven G

    2006-11-16

    The active fault traces on which earthquakes occur are generally not continuous, and are commonly composed of segments that are separated by discontinuities that appear as steps in map-view. Stress concentrations resulting from slip at such discontinuities may slow or stop rupture propagation and hence play a controlling role in limiting the length of earthquake rupture. Here I examine the mapped surface rupture traces of 22 historical strike-slip earthquakes with rupture lengths ranging between 10 and 420 km. I show that about two-thirds of the endpoints of strike-slip earthquake ruptures are associated with fault steps or the termini of active fault traces, and that there exists a limiting dimension of fault step (3-4 km) above which earthquake ruptures do not propagate and below which rupture propagation ceases only about 40 per cent of the time. The results are of practical importance to seismic hazard analysis where effort is spent attempting to place limits on the probable length of future earthquakes on mapped active faults. Physical insight to the dynamics of the earthquake rupture process is further gained with the observation that the limiting dimension appears to be largely independent of the earthquake rupture length. It follows that the magnitude of stress changes and the volume affected by those stress changes at the driving edge of laterally propagating ruptures are largely similar and invariable during the rupture process regardless of the distance an event has propagated or will propagate. PMID:17108963

  4. Renal failure after ruptured aneurysm.

    PubMed

    Abbott, W M; Abel, R M; Beck, C H; Fischer, J E

    1975-09-01

    The effectiveness of an intravenous nutritional program plus aggressive dialysis was studied in 32 patients with renal failure following ruptured abdominal aortic aneurysm. Each patient was managed postoperatively with a renal failure fluid regimen, consisting of the eight essential amino acids plus dextrose in conjunction with peritoneal dialysis and hemodialysis. This regimen induced salutary metabolic effects temporarily improving the patient's condition in most instances. No technical or septic complications associated with the intravenous dietary therapy occurred. However, the incidence of recovery of renal function was low, and the overall patient survival was only 12.5%. The experience indicates that although this program has been shown to be efficacious in some patients with acute renal failure, it seems of little benefit in those whose renal failure follows ruptured aortic aneurysm. PMID:808197

  5. Oesophageal rupture masquerading as STEMI.

    PubMed

    Skaug, Brian; Taylor, Kenneth R; Chandrasekaran, Somya

    2016-01-01

    A 67-year-old man presented to the emergency department, with acute onset of chest pain. Based on ECG changes suggestive of ST elevation myocardial infarction (STEMI), he was taken emergently to the cardiac catheterisation laboratory for coronary angiography. There he was found to have only non-obstructive coronary disease. Subsequent physical examination and review of his chest radiograph revealed subcutaneous emphysema, and CT scan revealed a distal oesophageal rupture and pneumomediastinum. After stabilisation in the intensive care unit (ICU), he was taken to the operating room for thoracotomy, chest tube placement and stenting of his oesophagus. He survived the incident and, after several weeks of ICU stay, recovered to a large extent. His case highlights the importance of considering oesophageal rupture in the differential diagnosis for acute onset of chest pain. PMID:27068730

  6. Spontaneous mid-oesophageal rupture.

    PubMed

    Holt, S; Millar, J W; Heading, R C; Charles, R G

    1978-08-01

    The clinical presentation and management of spontaneous rupture of the middle third of the oesophagus is described in two patients. Early presentation and treatment in one case led to uncomplicated recovery. In the other patient late presentation and diagnosis resulted in delayed surgical intervention with an unsuccessful outcome. The nature of this rare lesion is discussed and nine previously described cases are reviewed. PMID:733690

  7. Statistical wall shear stress maps of ruptured and unruptured middle cerebral artery aneurysms

    PubMed Central

    Goubergrits, L.; Schaller, J.; Kertzscher, U.; van den Bruck, N.; Poethkow, K.; Petz, Ch.; Hege, H.-Ch.; Spuler, A.

    2012-01-01

    Haemodynamics and morphology play an important role in the genesis, growth and rupture of cerebral aneurysms. The goal of this study was to generate and analyse statistical wall shear stress (WSS) distributions and shapes in middle cerebral artery (MCA) saccular aneurysms. Unsteady flow was simulated in seven ruptured and 15 unruptured MCA aneurysms. In order to compare these results, all geometries must be brought in a uniform coordinate system. For this, aneurysms with corresponding WSS data were transformed into a uniform spherical shape; then, all geometries were uniformly aligned in three-dimensional space. Subsequently, we compared statistical WSS maps and surfaces of ruptured and unruptured aneurysms. No significant (p > 0.05) differences exist between ruptured and unruptured aneurysms regarding radius and mean WSS. In unruptured aneurysms, statistical WSS map relates regions with high (greater than 3 Pa) WSS to the neck region. In ruptured aneurysms, additional areas with high WSS contiguous to regions of low (less than 1 Pa) WSS are found in the dome region. In ruptured aneurysms, we found significantly lower WSS. The averaged aneurysm surface of unruptured aneurysms is round shaped, whereas the averaged surface of ruptured cases is multi-lobular. Our results confirm the hypothesis of low WSS and irregular shape as the essential rupture risk parameters. PMID:21957117

  8. Rupture of vertical soap films

    NASA Astrophysics Data System (ADS)

    Rio, Emmanuelle

    2014-11-01

    Soap films are ephemeral and fragile objects. They tend to thin under gravity, which gives rise to the fascinating variations of colors at their interfaces but leads systematically to rupture. Even a child can create, manipulate and admire soap films and bubbles. Nevertheless, the reason why it suddenly bursts remains a mystery although the soap chosen to stabilize the film as well as the humidity of the air seem very important. One difficulty to study the rupture of vertical soap films is to control the initial solution. To avoid this problem we choose to study the rupture during the generation of the film at a controlled velocity. We have built an experiment, in which we measure the maximum length of the film together with its lifetime. The generation of the film is due to the presence of a gradient of surface concentration of surfactants at the liquid/air interface. This leads to a Marangoni force directed toward the top of the film. The film is expected to burst only when its weight is not balanced anymore by this force. We will show that this leads to the surprising result that the thicker films have shorter lifetimes than the thinner ones. It is thus the ability of the interface to sustain a surface concentration gradient of surfactants which controls its stability.

  9. The clinical and microbiological correlates of premature rupture of membranes.

    PubMed

    Karat, C; Madhivanan, P; Krupp, K; Poornima, S; Jayanthi, N V; Suguna, J S; Mathai, E

    2006-10-01

    Prematurity is the cause of 85% of neonatal morbidity and mortality. Premature rupture of the membranes (PROM) is associated with 30-40% of preterm deliveries. A case-control study conducted between July 2002 and 2003 examined the correlates and risk factors for PROM in Mysore, India. WBCs in vaginal fluid, leucocytes in urine, UTI and infection with E. coli, S. aureus, C. albicans and BV were significantly associated with PROM. BV, E. coli and WBCs in vaginal fluid were independent risk factors. Screening and treatment of BV and E. coli infection in pregnancy may reduce the risk of PROM. PMID:17185848

  10. [Delayed spontaneous rupture of the bladder following augmentation enterocystoplasty].

    PubMed

    Leibovitch, I; Ramon, J; Ben Chaim, J; Goldwasser, B

    1990-08-01

    Delayed spontaneous rupture of the urinary bladder following augmentation enterocystoplasty is a serious life-threatening complication of uncertain etiology. Multiple factors are believed to contribute to the mechanism of bladder perforation. Ruptured augmented bladders share a common urodynamic pattern of high leak point pressure of the urethra, with sensory and mechanical tolerance of high filling pressure. This combination seems to be the main predisposing factor for spontaneous perforation. Other risk factors, including catheter trauma during intermittent self-catheterization, urinary retention due to mucus retention or noncompliance with the catheterization protocol, chronic infection, and decreased sensation of bladder filling, may play roles in the mechanism of rupture. Clinically, patients present with sepsis, abdominal pain and distension, ileus, fever, oliguria and peritoneal irritation. The diagnosis is made on low pressure cystography, although failure of cystography to demonstrate extravasation is not unusual. Aggressive surgical treatment consists of immediate exploration, primary repair of the perforation, drainage of the perivesical space, suprapubic cystostomy and broad-spectrum antibiotics. Longterm management includes a strict intermittent catheterization schedule, anticholinergic therapy and urodynamic evaluation. Failure to achieve a low pressure storage reservoir by conservative means entails an increased risk of recurrent perforation. In such cases further surgical intervention should be considered. We present a 21-year-old paraplegic man 5 months after augmentation enterocystoplasty who required operation because of spontaneous rupture of the augmented bladder. Spontaneous delayed rupture of the bladder should be considered in the differential diagnosis of acute abdomen in patients after augmentation enterocystoplasty. Early surgical treatment and subsequent monitoring of the low pressure reservoir are recommended. PMID:2227670

  11. Inflammatory cell phenotypes in AAAs; their role and potential as targets for therapy

    PubMed Central

    Dale, Matthew A; Ruhlman, Melissa K.; Baxter, B. Timothy

    2015-01-01

    Abdominal aortic aneurysms are characterized by chronic inflammatory cell infiltration. AAA is typically an asymptomatic disease and caused approximately 15,000 deaths annually in the U.S. Previous studies have examined both human and murine aortic tissue for the presence of various inflammatory cell types. Studies show that in both human and experimental AAAs, prominent inflammatory cell infiltration, such as CD4+ T cells and macrophages, occurs in the damaged aortic wall. These cells have the ability to undergo phenotypic modulation based on microenvironmental cues, potentially influencing disease progression. Pro-inflammatory CD4+ T cells and classically activated macrophages dominate the landscape of aortic infiltrates. The skew to pro-inflammatory phenotypes alters disease progression and plays a role in causing chronic inflammation. The local cytokine production and presence of inflammatory mediators, such as extracellular matrix breakdown products, influence the uneven balance of the inflammatory infiltrate phenotypes. Understanding and developing new strategies that target the pro-inflammatory phenotype could provide useful therapeutic targets for a disease with no current pharmacological intervention. PMID:26044582

  12. AAA ATPases regulate membrane association of yeast oxysterol binding proteins and sterol metabolism.

    PubMed

    Wang, Penghua; Zhang, Yong; Li, Hongzhe; Chieu, Hai Kee; Munn, Alan L; Yang, Hongyuan

    2005-09-01

    The yeast genome encodes seven oxysterol binding protein homologs, Osh1p-Osh7p, which have been implicated in regulating intracellular lipid and vesicular transport. Here, we show that both Osh6p and Osh7p interact with Vps4p, a member of the AAA (ATPases associated with a variety of cellular activities) family. The coiled-coil domain of Osh7p was found to interact with Vps4p in a yeast two-hybrid screen and the interaction between Osh7p and Vps4p appears to be regulated by ergosterol. Deletion of VPS4 induced a dramatic increase in the membrane-associated pools of Osh6p and Osh7p and also caused a decrease in sterol esterification, which was suppressed by overexpression of OSH7. Lastly, overexpression of the coiled-coil domain of Osh7p (Osh7pCC) resulted in a multivesicular body sorting defect, suggesting a dominant negative role of Osh7pCC possibly through inhibiting Vps4p function. Our data suggest that a common mechanism may exist for AAA proteins to regulate the membrane association of yeast OSBP proteins and that these two protein families may function together to control subcellular lipid transport. PMID:16096648

  13. TRIP13 is a protein-remodeling AAA+ ATPase that catalyzes MAD2 conformation switching

    PubMed Central

    Ye, Qiaozhen; Rosenberg, Scott C; Moeller, Arne; Speir, Jeffrey A; Su, Tiffany Y; Corbett, Kevin D

    2015-01-01

    The AAA+ family ATPase TRIP13 is a key regulator of meiotic recombination and the spindle assembly checkpoint, acting on signaling proteins of the conserved HORMA domain family. Here we present the structure of the Caenorhabditis elegans TRIP13 ortholog PCH-2, revealing a new family of AAA+ ATPase protein remodelers. PCH-2 possesses a substrate-recognition domain related to those of the protein remodelers NSF and p97, while its overall hexameric architecture and likely structural mechanism bear close similarities to the bacterial protein unfoldase ClpX. We find that TRIP13, aided by the adapter protein p31(comet), converts the HORMA-family spindle checkpoint protein MAD2 from a signaling-active ‘closed’ conformer to an inactive ‘open’ conformer. We propose that TRIP13 and p31(comet) collaborate to inactivate the spindle assembly checkpoint through MAD2 conformational conversion and disassembly of mitotic checkpoint complexes. A parallel HORMA protein disassembly activity likely underlies TRIP13's critical regulatory functions in meiotic chromosome structure and recombination. DOI: http://dx.doi.org/10.7554/eLife.07367.001 PMID:25918846

  14. Mechanism of the AAA+ ATPases pontin and reptin in the biogenesis of H/ACA RNPs

    PubMed Central

    Machado-Pinilla, Rosario; Liger, Dominique; Leulliot, Nicolas; Meier, U. Thomas

    2012-01-01

    The AAA+ ATPases pontin and reptin function in a staggering array of cellular processes including chromatin remodeling, transcriptional regulation, DNA damage repair, and assembly of macromolecular complexes, such as RNA polymerase II and small nucleolar (sno) RNPs. However, the molecular mechanism for all of these AAA+ ATPase associated activities is unknown. Here we document that, during the biogenesis of H/ACA RNPs (including telomerase), the assembly factor SHQ1 holds the pseudouridine synthase NAP57/dyskerin in a viselike grip, and that pontin and reptin (as components of the R2TP complex) are required to pry NAP57 from SHQ1. Significantly, the NAP57 domain captured by SHQ1 harbors most mutations underlying X-linked dyskeratosis congenita (X-DC) implicating the interface between the two proteins as a target of this bone marrow failure syndrome. Homing in on the essential first steps of H/ACA RNP biogenesis, our findings provide the first insight into the mechanism of action of pontin and reptin in the assembly of macromolecular complexes. PMID:22923768

  15. Going the distance: validation of Acuros and AAA at an extended SSD of 400 cm.

    PubMed

    Lamichhane, Narottam; Patel, Vivek N; Studenski, Matthew T

    2016-01-01

    Accurate dose calculation and treatment delivery is essential for total body irradia-tion (TBI). In an effort to verify the accuracy of TBI dose calculation at our institu-tion, we evaluated both the Varian Eclipse AAA and Acuros algorithms to predict dose distributions at an extended source-to-surface distance (SSD) of 400 cm. Measurements were compared to calculated values for a 6 MV beam in physical and virtual phantoms at 400 cm SSD using open beams for both 5 × 5 and 40 × 40cm2 field sizes. Inline and crossline profiles were acquired at equivalent depths of 5 cm, 10 cm, and 20 cm. Depth-dose curves were acquired using EBT2 film and an ion chamber for both field sizes. Finally, a RANDO phantom was used to simulate an actual TBI treatment. At this extended SSD, care must be taken using the planning system as there is good relative agreement between measured and calculated profiles for both algorithms, but there are deviations in terms of the absolute dose. Acuros has better agreement than AAA in the penumbra region. PMID:27074473

  16. Moyamoya disease-associated protein mysterin/RNF213 is a novel AAA+ ATPase, which dynamically changes its oligomeric state

    NASA Astrophysics Data System (ADS)

    Morito, Daisuke; Nishikawa, Kouki; Hoseki, Jun; Kitamura, Akira; Kotani, Yuri; Kiso, Kazumi; Kinjo, Masataka; Fujiyoshi, Yoshinori; Nagata, Kazuhiro

    2014-03-01

    Moyamoya disease is an idiopathic human cerebrovascular disorder that is characterized by progressive stenosis and abnormal collateral vessels. We recently identified mysterin/RNF213 as its first susceptibility gene, which encodes a 591-kDa protein containing enzymatically active P-loop ATPase and ubiquitin ligase domains and is involved in proper vascular development in zebrafish. Here we demonstrate that mysterin further contains two tandem AAA+ ATPase modules and forms huge ring-shaped oligomeric complex. AAA+ ATPases are known to generally mediate various biophysical and mechanical processes with the characteristic ring-shaped structure. Fluorescence correlation spectroscopy and biochemical evaluation suggested that mysterin dynamically changes its oligomeric forms through ATP/ADP binding and hydrolysis cycles. Thus, the moyamoya disease-associated gene product is a unique protein that functions as ubiquitin ligase and AAA+ ATPase, which possibly contributes to vascular development through mechanical processes in the cell.

  17. An atomic model AAA-ATPase/20S core particle sub-complex of the 26S proteasome.

    PubMed

    Förster, Friedrich; Lasker, Keren; Beck, Florian; Nickell, Stephan; Sali, Andrej; Baumeister, Wolfgang

    2009-10-16

    The 26S proteasome is the most downstream element of the ubiquitin-proteasome pathway of protein degradation. It is composed of the 20S core particle (CP) and the 19S regulatory particle (RP). The RP consists of 6 AAA-ATPases and at least 13 non-ATPase subunits. Based on a cryo-EM map of the 26S proteasome, structures of homologs, and physical protein-protein interactions we derive an atomic model of the AAA-ATPase-CP sub-complex. The ATPase order in our model (Rpt1/Rpt2/Rpt6/Rpt3/Rpt4/Rpt5) is in excellent agreement with the recently identified base-precursor complexes formed during the assembly of the RP. Furthermore, the atomic CP-AAA-ATPase model suggests that the assembly chaperone Nas6 facilitates CP-RP association by enhancing the shape complementarity between Rpt3 and its binding CP alpha subunits partners. PMID:19653995

  18. An atomic model AAA-ATPase/20S core particle sub-complex of the 26S proteasome

    SciTech Connect

    Foerster, Friedrich; Lasker, Keren; Beck, Florian; Nickell, Stephan; Sali, Andrej; Baumeister, Wolfgang

    2009-10-16

    The 26S proteasome is the most downstream element of the ubiquitin-proteasome pathway of protein degradation. It is composed of the 20S core particle (CP) and the 19S regulatory particle (RP). The RP consists of 6 AAA-ATPases and at least 13 non-ATPase subunits. Based on a cryo-EM map of the 26S proteasome, structures of homologs, and physical protein-protein interactions we derive an atomic model of the AAA-ATPase-CP sub-complex. The ATPase order in our model (Rpt1/Rpt2/Rpt6/Rpt3/Rpt4/Rpt5) is in excellent agreement with the recently identified base-precursor complexes formed during the assembly of the RP. Furthermore, the atomic CP-AAA-ATPase model suggests that the assembly chaperone Nas6 facilitates CP-RP association by enhancing the shape complementarity between Rpt3 and its binding CP alpha subunits partners.

  19. Ground motion hazard from supershear rupture

    USGS Publications Warehouse

    Andrews, D.J.

    2010-01-01

    An idealized rupture, propagating smoothly near a terminal rupture velocity, radiates energy that is focused into a beam. For rupture velocity less than the S-wave speed, radiated energy is concentrated in a beam of intense fault-normal velocity near the projection of the rupture trace. Although confined to a narrow range of azimuths, this beam diverges and attenuates. For rupture velocity greater than the S-wave speed, radiated energy is concentrated in Mach waves forming a pair of beams propagating obliquely away from the fault. These beams do not attenuate until diffraction becomes effective at large distance. Events with supershear and sub-Rayleigh rupture velocity are compared in 2D plane-strain calculations with equal stress drop, fracture energy, and rupture length; only static friction is changed to determine the rupture velocity. Peak velocity in the sub-Rayleigh case near the termination of rupture is larger than peak velocity in the Mach wave in the supershear case. The occurrence of supershear rupture propagation reduces the most intense peak ground velocity near the fault, but it increases peak velocity within a beam at greater distances. ?? 2010.

  20. Mycotic Aneurysm of the Celiac Trunk: From Early CT Sign to Rupture

    SciTech Connect

    Serafino, Gianpiero Vroegindeweij, Dammis; Boks, Simone; Harst, Erwin van der

    2005-06-15

    We present a case of the rapid development and rupture of a mycotic celiac trunk aneurysm. Initiallyon multislice computed tomography (ms-CT) there was a normal celiac trunk with minimal haziness of the surrounding fat. Only 2 weeks later the patient went into hypovolemic shock due to a ruptured celiac aneurysm. Although aneurysms of the visceral arteries are rare, they are of major clinical importance as they carry a life-threatening risk of rupture. This case illustrates the use of ms-CT in detecting and evaluating visceral aneurysms, in order to prevent emergency operation.

  1. Traumatic bilateral Achilles tendon rupture in a young athlete treated with percutaneous tenorrhaphy

    PubMed Central

    MACERA, ARMANDO; CARULLI, CHRISTIAN; MATASSI, FABRIZIO; VENEZIANI, CARLO; INNOCENTI, MASSIMO

    2015-01-01

    While rupture of the Achilles tendon is one of the most frequent injuries sustained in sports and physical activity, bilateral Achilles tendon rupture is uncommon. We present the case of a 33-year-old man who sustained a bilateral Achilles tendon rupture in the absence of predisposing factors. The lesions were managed by percutaneous tenorrhaphy and casting. Six months after surgery he was able to return to his daily-life activities and to perform light sports activity. The Authors review the current literature on the management of this rare condition in young people, with or without risk factors. PMID:26904529

  2. Coil Embolization Treatment in Pulmonary Artery Branch Rupture During Swan-Ganz Catheterization

    SciTech Connect

    Gottwalles, Yannick; Wunschel-Joseph, Marie-Eve; Hanssen, Michel

    2000-11-15

    Rupture of the pulmonary artery or one of its branches during Swan-Ganz catheterization is a complication that is rare but remains fatal in almost 50% of cases. The risk factors and mechanisms involved in the pathogenesis of this accident have been widely reported. Management is twofold: resuscitation procedures and specific medical or even surgical treatment. We report a case of pulmonary artery rupture occurring during Swan-Ganz catheterization that was treated by coil embolization. This technique, which is quick and simple to use, would appear to be very promising. This is the first case of successful emergency treatment of pulmonary artery rupture using an endovascular technique.

  3. Progressive visual loss following rupture of an intracranial dermoid cyst.

    PubMed

    Skovrlj, Branko; Mascitelli, Justin R; Steinberger, Jeremy M; Weiss, Nirit

    2014-01-01

    A 51-year-old man with several months of headache and progressive visual decline was found to have bilateral optic disc pallor with significant impairment of visual acuity. Despite a thorough ophthalmologic evaluation, the cause of visual loss could not be elucidated. MRI of the brain revealed a lesion in the left anterior Sylvian fissure as well as disseminated foci of subarachnoid fat consistent with a diagnosis of a ruptured dermoid cyst. The decision for open surgical resection was chosen to minimize the risk of cyst re-rupture and further visual or neurologic decline. The diagnosis of dermoid cyst was confirmed at the time of surgery. Vasospasm-induced ischemia of the optic nerves, optic chiasm or bilateral optic tracts secondary to the inflammatory reaction following cyst rupture is the most likely mechanism of visual loss in this patient. To the authors' knowledge, this report represents the first reported case of visual loss secondary to rupture of an intracranial dermoid cyst not related to mass effect of the tumor on the optic apparatus, visual pathways or visual cortex. PMID:23896550

  4. Origin and Functional Evolution of the Cdc48/p97/VCP AAA+ Protein Unfolding and Remodeling Machine.

    PubMed

    Barthelme, Dominik; Sauer, Robert T

    2016-05-01

    The AAA+ Cdc48 ATPase (alias p97 or VCP) is a key player in multiple ubiquitin-dependent cell signaling, degradation, and quality control pathways. Central to these broad biological functions is the ability of Cdc48 to interact with a large number of adaptor proteins and to remodel macromolecular proteins and their complexes. Different models have been proposed to explain how Cdc48 might couple ATP hydrolysis to forcible unfolding, dissociation, or remodeling of cellular clients. In this review, we provide an overview of possible mechanisms for substrate unfolding/remodeling by this conserved and essential AAA+ protein machine and their adaption and possible biological function throughout evolution. PMID:26608813

  5. The AAA-ATPase molecular chaperone Cdc48/p97 disassembles sumoylated centromeres, decondenses heterochromatin, and activates ribosomal RNA genes

    PubMed Central

    Mérai, Zsuzsanna; Chumak, Nina; García-Aguilar, Marcelina; Hsieh, Tzung-Fu; Nishimura, Toshiro; Schoft, Vera K.; Bindics, János; Ślusarz, Lucyna; Arnoux, Stéphanie; Opravil, Susanne; Mechtler, Karl; Zilberman, Daniel; Fischer, Robert L.; Tamaru, Hisashi

    2014-01-01

    Centromeres mediate chromosome segregation and are defined by the centromere-specific histone H3 variant (CenH3)/centromere protein A (CENP-A). Removal of CenH3 from centromeres is a general property of terminally differentiated cells, and the persistence of CenH3 increases the risk of diseases such as cancer. However, active mechanisms of centromere disassembly are unknown. Nondividing Arabidopsis pollen vegetative cells, which transport engulfed sperm by extended tip growth, undergo loss of CenH3; centromeric heterochromatin decondensation; and bulk activation of silent rRNA genes, accompanied by their translocation into the nucleolus. Here, we show that these processes are blocked by mutations in the evolutionarily conserved AAA-ATPase molecular chaperone, CDC48A, homologous to yeast Cdc48 and human p97 proteins, both of which are implicated in ubiquitin/small ubiquitin-like modifier (SUMO)-targeted protein degradation. We demonstrate that CDC48A physically associates with its heterodimeric cofactor UFD1-NPL4, known to bind ubiquitin and SUMO, as well as with SUMO1-modified CenH3 and mutations in NPL4 phenocopy cdc48a mutations. In WT vegetative cell nuclei, genetically unlinked ribosomal DNA (rDNA) loci are uniquely clustered together within the nucleolus and all major rRNA gene variants, including those rDNA variants silenced in leaves, are transcribed. In cdc48a mutant vegetative cell nuclei, however, these rDNA loci frequently colocalized with condensed centromeric heterochromatin at the external periphery of the nucleolus. Our results indicate that the CDC48ANPL4 complex actively removes sumoylated CenH3 from centromeres and disrupts centromeric heterochromatin to release bulk rRNA genes into the nucleolus for ribosome production, which fuels single nucleus-driven pollen tube growth and is essential for plant reproduction. PMID:25344531

  6. The AAA-ATPase molecular chaperone Cdc48/p97 disassembles sumoylated centromeres, decondenses heterochromatin, and activates ribosomal RNA genes.

    PubMed

    Mérai, Zsuzsanna; Chumak, Nina; García-Aguilar, Marcelina; Hsieh, Tzung-Fu; Nishimura, Toshiro; Schoft, Vera K; Bindics, János; Slusarz, Lucyna; Arnoux, Stéphanie; Opravil, Susanne; Mechtler, Karl; Zilberman, Daniel; Fischer, Robert L; Tamaru, Hisashi

    2014-11-11

    Centromeres mediate chromosome segregation and are defined by the centromere-specific histone H3 variant (CenH3)/centromere protein A (CENP-A). Removal of CenH3 from centromeres is a general property of terminally differentiated cells, and the persistence of CenH3 increases the risk of diseases such as cancer. However, active mechanisms of centromere disassembly are unknown. Nondividing Arabidopsis pollen vegetative cells, which transport engulfed sperm by extended tip growth, undergo loss of CenH3; centromeric heterochromatin decondensation; and bulk activation of silent rRNA genes, accompanied by their translocation into the nucleolus. Here, we show that these processes are blocked by mutations in the evolutionarily conserved AAA-ATPase molecular chaperone, CDC48A, homologous to yeast Cdc48 and human p97 proteins, both of which are implicated in ubiquitin/small ubiquitin-like modifier (SUMO)-targeted protein degradation. We demonstrate that CDC48A physically associates with its heterodimeric cofactor UFD1-NPL4, known to bind ubiquitin and SUMO, as well as with SUMO1-modified CenH3 and mutations in NPL4 phenocopy cdc48a mutations. In WT vegetative cell nuclei, genetically unlinked ribosomal DNA (rDNA) loci are uniquely clustered together within the nucleolus and all major rRNA gene variants, including those rDNA variants silenced in leaves, are transcribed. In cdc48a mutant vegetative cell nuclei, however, these rDNA loci frequently colocalized with condensed centromeric heterochromatin at the external periphery of the nucleolus. Our results indicate that the CDC48A(NPL4) complex actively removes sumoylated CenH3 from centromeres and disrupts centromeric heterochromatin to release bulk rRNA genes into the nucleolus for ribosome production, which fuels single nucleus-driven pollen tube growth and is essential for plant reproduction. PMID:25344531

  7. Soft, Brown Rupture: Clinical Signs and Symptoms Associated with Ruptured PIP Breast Implants

    PubMed Central

    Duncan, Robert T.; Feig, Christine; Reintals, Michelle; Hill, Sarah

    2014-01-01

    Background: Preoperative signs and symptoms of patients with Poly Implant Prothese (PIP) implants could be predictive of device failure. Based on clinical observation and intraoperative findings 4 hypotheses were raised: (1) Preoperative clinical signs including acquired asymmetry, breast enlargement, fullness of the lower pole, decreased mound projection, and change in breast consistency could be indicative of implant rupture. (2) Device failure correlates with a low preoperative Baker grade of capsule. (3) Brown-stained implants are more prone to implant failure. (4) The brown gel could be indicative of iodine ingression through a substandard elastomer shell. Methods: Preoperative clinical signs were compared with intraoperative findings for 27 patients undergoing PIP implant explantation. Results: Acquired asymmetry (P = 0.0003), breast enlargement (P = 0.0002), fuller lower pole (P < 0.0001), and loss of lateral projection (P < 0.0001) were all significantly predictive of device failure. Capsule Baker grade was lower preoperatively for ruptured implants. The lack of palpable and visible preoperative capsular contracture could be secondary to the elastic nature of the capsular tissue found. Brown implants failed significantly more often than white implants. Analysis of brown gel revealed the presence of iodine, suggesting povidone iodine ingression at implantation. Conclusions: Preoperative signs can be predictive of PIP implant failure. Brown-stained implants are more prone to rupture. The presence of iodine in the gel suggests unacceptable permeability of the shell early in the implant’s life span. A noninvasive screening test to detect brown implants in situ could help identify implants at risk of failure in those who elect to keep their implants. PMID:25506532

  8. [Uterine rupture plugged by omentum in a rudimentary horn pregnancy: About a rare case].

    PubMed

    Le Mitouard, M; Huissoud, C; Fichez, A; Roumieu, F; Allias, F; Rudigoz, R C; Caloone, J

    2016-05-01

    Pregnancy in a rudimentary horn of a pseudo-horned uterus is a rare obstetrical situation, for which, maternal-fetal prognosis is altered by the risk of uterine rupture. We report a rare case of pregnancy in a rudimentary horn with birth of a living child at 28 weeks of amenorrhea. During caesarean, uterine rupture plugged by the omentum was observed. We discuss from this case obstetric management of this pathology. PMID:27021927

  9. [Tendinosis and ruptures of the Achilles tendon].

    PubMed

    Amlang, M H; Zwipp, H

    2012-02-01

    Tendinosis of the Achilles tendon is a degenerative-reparative structural change of the tendon with microdefects, increases in cross-section due to cicatricial tendon regeneration, neoangiogenesis and reduction of elasticity. The previously used term tendinitis is only rarely used for the chronic form since signs of inflammation such as redness and hyperthermia or elevated levels of inflammatory parameters on laboratory testing are generally absent. Duplex sonography with visualization of the neovascularization has become a valuable supplement not only for diagnostics but also for therapy planning. The classic, conservative therapy for painful tendinosis consists of oral anti-inflammatory drugs, pain-adapted load reduction, raising the heel, stretching the calf musculature, and various physiotherapeutic interventions. When conservative treatment over a period of 4 - 6 months fails to produce any or non-adequate pain relief, an indication for surgical treatment should be considered. In the therapy for fresh ruptures of the Achilles tendon further developments in minimally invasive techniques have led to a worldwide paradigm change over the past 10 years. The decisive advantage of minimally invasive surgical techniques is the lower risk of wound infection as compared to the sutures of the open technique. When compared with conservative functional therapy the minimally invasive repair has the advantage of being less dependent on the compliance of the patient since, in the early phase of tendon healing the suture prevents a separation of the tendon ends upon controlled movements. However, not every patient with a ruptured Achilles tendon should be treated with a minimally invasive repair. Open tendon reconstruction and functional conservative therapy are still justified when the correct indication is given. PMID:22344862

  10. TU-C-BRE-05: Clinical Implications of AAA Commissioning Errors and Ability of Common Commissioning ' Credentialing Procedures to Detect Them

    SciTech Connect

    McVicker, A; Oldham, M; Yin, F; Adamson, J

    2014-06-15

    Purpose: To test the ability of the TG-119 commissioning process and RPC credentialing to detect errors in the commissioning process for a commercial Treatment Planning System (TPS). Methods: We introduced commissioning errors into the commissioning process for the Anisotropic Analytical Algorithm (AAA) within the Eclipse TPS. We included errors in Dosimetric Leaf Gap (DLG), electron contamination, flattening filter material, and beam profile measurement with an inappropriately large farmer chamber (simulated using sliding window smoothing of profiles). We then evaluated the clinical impact of these errors on clinical intensity modulated radiation therapy (IMRT) plans (head and neck, low and intermediate risk prostate, mesothelioma, and scalp) by looking at PTV D99, and mean and max OAR dose. Finally, for errors with substantial clinical impact we determined sensitivity of the RPC IMRT film analysis at the midpoint between PTV and OAR using a 4mm distance to agreement metric, and of a 7% TLD dose comparison. We also determined sensitivity of the 3 dose planes of the TG-119 C-shape IMRT phantom using gamma criteria of 3% 3mm. Results: The largest clinical impact came from large changes in the DLG with a change of 1mm resulting in up to a 5% change in the primary PTV D99. This resulted in a discrepancy in the RPC TLDs in the PTVs and OARs of 7.1% and 13.6% respectively, which would have resulted in detection. While use of incorrect flattening filter caused only subtle errors (<1%) in clinical plans, the effect was most pronounced for the RPC TLDs in the OARs (>6%). Conclusion: The AAA commissioning process within the Eclipse TPS is surprisingly robust to user error. When errors do occur, the RPC and TG-119 commissioning credentialing criteria are effective at detecting them; however OAR TLDs are the most sensitive despite the RPC currently excluding them from analysis.

  11. Spontaneous rupture of a splenotic nodule.

    PubMed Central

    Lanigan, D. J.

    1990-01-01

    A case is presented of spontaneous rupture of splenic tissue occurring 14 years after a splenectomy was carried out for trauma. Spontaneous rupture of a splenotic nodule has not previously been described and it may be added to the list of causes of spontaneous haemoperitoneum. The incidence and function of residual splenic tissue are briefly discussed and other causes of splenic rupture are outlined. PMID:2267217

  12. Investigation of cryogenic rupture disc design

    NASA Technical Reports Server (NTRS)

    Keough, J. B.; Oldland, A. H.

    1973-01-01

    Rupture disc designs of both the active (command actuated) and passive (pressure ruptured) types were evaluated for performance characteristics at cryogenic temperatures and for capability to operate in a variety of cryogens, including gaseous and liquid fluorine. The test results, coupled with information from literature and industry searches, were used to establish a statement of design criteria and recommended practices for application of rupture discs to cryogenic rocket propellant feed and vent systems.

  13. Analysis of uterine rupture at university teaching hospital Pakistan

    PubMed Central

    Aziz, Nousheen; Yousfani, Sajida

    2015-01-01

    Objective: To determine the risk factors, management modalities, fetomaternal outcome of uterine rupture cases at University teaching hospital in Pakistan. Methods: This retrospective descriptive study was conducted at the Department of Gynaecology and Obstetrics Liaquat University of Medical and Health Sciences (LUMHS) for a period of one year from January 1st to December 31st 2012. Main outcome measures were frequency, age, parity, booking status, risk factors, management modalities, fetal and maternal mortality associated with uterine rupture. The data was collected on pre-designed proforma analysed using SPSS Version 16 statistical package. Results: The frequency of ruptured uteri was calculated to be 0.67%, giving a ratio of 1:148 deliveries. Highest incidence was found in age group 25-30 (44.26%) with mean age of 30.36 years. and parity group 2-3 (57.37%) with mean parity 4.08. The risk factors for ruptured uterus include Caesarean section 43(70.49%), injudicious use of oxytocin 33(54.09%), obstructed labour 15 (24.59%) and multiparty 18 (29.50%). Repair of uterus was performed in 47(77.04%) cases. Maternal case fatality was 5(8.19%), while foetal wastage was 51 (83.60%). Conclusion: This study confirms the existence of a serious preventable obstetric problem, with significant maternal mortality and foetal wastage. Integrated efforts include Health education, focused antenatal care, skilled attendance, avoidance of injudicious use of oxytocin, and need of hospital based deliveries in patients with caesarean section which should be intensified to reduce this drastic obstetrical complication. PMID:26430430

  14. Acute Pectoralis Major Rupture Captured on Video

    PubMed Central

    Valencia Mora, María

    2016-01-01

    Pectoralis major (PM) ruptures are uncommon injuries, although they are becoming more frequent. We report a case of a PM rupture in a young male who presented with axillar pain and absence of the anterior axillary fold after he perceived a snap while lifting 200 kg in the bench press. Diagnosis of PM rupture was suspected clinically and confirmed with imaging studies. The patient was treated surgically, reinserting the tendon to the humerus with suture anchors. One-year follow-up showed excellent results. The patient was recording his training on video, so we can observe in detail the most common mechanism of injury of PM rupture. PMID:27595030

  15. Rupture dynamics in model polymer systems.

    PubMed

    Borah, Rupam; Debnath, Pallavi

    2016-05-11

    In this paper we explore the rupture dynamics of a model polymer system to capture the microscopic mechanism during relative motion of surfaces at the single polymer level. Our model is similar to the model for friction introduced by Filippov, Klafter, and Urbakh [Filippov et al., Phys. Rev. Lett., 2004, 92, 135503]; but with an important generalization to a flexible transducer (modelled as a bead spring polymer) which is attached to a fixed rigid planar substrate by interconnecting bonds (modelled as harmonic springs), and pulled by a constant force FT. Bonds are allowed to rupture stochastically. The model is simulated, and the results for a certain set of parameters exhibit a sequential rupture mechanism resulting in rupture fronts. A mean field formalism is developed to study these rupture fronts and the possible propagating solutions for the coupled bead and bond dynamics, where the coupling excludes an exact analytical treatment. Numerical solutions to mean field equations are obtained by standard numerical techniques, and they agree well with the simulation results which show sequential rupture. Within a travelling wave formalism based on the Tanh method, we show that the velocity of the rupture front can be obtained in closed form. The derived expression for the rupture front velocity gives good agreement with the stochastic and mean field results, when the rupture is sequential, while propagating solutions for bead and bond dynamics are shown to agree under certain conditions. PMID:27087684

  16. Monte Carlo evaluation of the AAA treatment planning algorithm in a heterogeneous multilayer phantom and IMRT clinical treatments for an Elekta SL25 linear accelerator

    SciTech Connect

    Sterpin, E.; Tomsej, M.; Smedt, B. de; Reynaert, N.; Vynckier, S.

    2007-05-15

    The Anisotropic Analytical Algorithm (AAA) is a new pencil beam convolution/superposition algorithm proposed by Varian for photon dose calculations. The configuration of AAA depends on linear accelerator design and specifications. The purpose of this study was to investigate the accuracy of AAA for an Elekta SL25 linear accelerator for small fields and intensity modulated radiation therapy (IMRT) treatments in inhomogeneous media. The accuracy of AAA was evaluated in two studies. First, AAA was compared both with Monte Carlo (MC) and the measurements in an inhomogeneous phantom simulating lung equivalent tissues and bone ribs. The algorithm was tested under lateral electronic disequilibrium conditions, using small fields (2x2 cm{sup 2}). Good agreement was generally achieved for depth dose and profiles, with deviations generally below 3% in lung inhomogeneities and below 5% at interfaces. However, the effects of attenuation and scattering close to the bone ribs were not fully taken into account by AAA, and small inhomogeneities may lead to planning errors. Second, AAA and MC were compared for IMRT plans in clinical conditions, i.e., dose calculations in a computed tomography scan of a patient. One ethmoid tumor, one orophaxynx and two lung tumors are presented in this paper. Small differences were found between the dose volume histograms. For instance, a 1.7% difference for the mean planning target volume dose was obtained for the ethmoid case. Since better agreement was achieved for the same plans but in homogeneous conditions, these differences must be attributed to the handling of inhomogeneities by AAA. Therefore, inherent assumptions of the algorithm, principally the assumption of independent depth and lateral directions in the scaling of the kernels, were slightly influencing AAA's validity in inhomogeneities. However, AAA showed a good accuracy overall and a great ability to handle small fields in inhomogeneous media compared to other pencil beam convolution

  17. Characterisation of pectins extracted from banana peels (Musa AAA) under different conditions using an experimental design.

    PubMed

    Happi Emaga, Thomas; Ronkart, Sébastien N; Robert, Christelle; Wathelet, Bernard; Paquot, Michel

    2008-05-15

    An experimental design was used to study the influence of pH (1.5 and 2.0), temperature (80 and 90°C) and time (1 and 4h) on extraction of pectin from banana peels (Musa AAA). Yield of extracted pectins, their composition (neutral sugars, galacturonic acid, and degree of esterification) and some macromolecular characteristics (average molecular weight, intrinsic viscosity) were determined. It was found that extraction pH was the most important parameter influencing yield and pectin chemical composition. Lower pH values negatively affected the galacturonic acid content of pectin, but increased the pectin yield. The values of degree of methylation decreased significantly with increasing temperature and time of extraction. The average molecular weight ranged widely from 87 to 248kDa and was mainly influenced by pH and extraction time. PMID:26059123

  18. The catalytic power of magnesium chelatase: a benchmark for the AAA(+) ATPases.

    PubMed

    Adams, Nathan B P; Brindley, Amanda A; Hunter, C Neil; Reid, James D

    2016-06-01

    In the first committed reaction of chlorophyll biosynthesis, magnesium chelatase couples ATP hydrolysis to the thermodynamically unfavorable Mg(2+) insertion into protoporphyrin IX (ΔG°' of circa 25-33 kJ·mol(-1) ). We explored the thermodynamic constraints on magnesium chelatase and demonstrate the effect of nucleotide hydrolysis on both the reaction kinetics and thermodynamics. The enzyme produces a significant rate enhancement (kcat /kuncat of 400 × 10(6) m) and a catalytic rate enhancement, kcat/KmDIXK0.5Mgkuncat, of 30 × 10(15) m(-1) , increasing to 300 × 10(15) m(-1) with the activator protein Gun4. This is the first demonstration of the thermodynamic benefit of ATP hydrolysis in the AAA(+) family. PMID:27176620

  19. Student-Athlete Perceptions of a Summer Pre-Enrollment Experience at an NCAA Division I-AAA Institution

    ERIC Educational Resources Information Center

    Dalgety, Michael Franklin

    2012-01-01

    The purpose of this exploratory qualitative study was to examine student-athlete perceptions of the role of summer pre-enrollment in their adjustment and transition to college. The study focused on student-athletes who received athletically-related financial aid at a National Collegiate Athletic Association (NCAA) Division I-AAA institution. The…

  20. Nucleotide-dependent interactions between a fork junction–RNA polymerase complex and an AAA+ transcriptional activator protein

    PubMed Central

    Cannon, W. V.; Schumacher, J.; Buck, M.

    2004-01-01

    Enhancer-dependent transcriptional activators that act upon the σ54 bacterial RNA polymerase holoenzyme belong to the extensive AAA+ superfamily of mechanochemical ATPases. Formation and collapse of the transition state for ATP hydrolysis engenders direct interactions between AAA+ activators and the σ54 factor, required for RNA polymerase isomerization. A DNA fork junction structure present within closed complexes serves as a nucleation point for the DNA melting seen in open promoter complexes and restricts spontaneous activator-independent RNA polymerase isomerization. We now provide physical evidence showing that the ADP·AlFx bound form of the AAA+ domain of the transcriptional activator protein PspF changes interactions between σ54-RNA polymerase and a DNA fork junction structure present in the closed promoter complex. The results suggest that one functional state of the nucleotide-bound activator serves to alter DNA binding by σ54 and σ54-RNA polymerase and appears to drive events that precede DNA opening. Clear evidence for a DNA-interacting activity in the AAA+ domain of PspF was obtained, suggesting that PspF may make a direct contact to the DNA component of a basal promoter complex to promote changes in σ54-RNA polymerase–DNA interactions that favour open complex formation. We also provide evidence for two distinct closed promoter complexes with differing stabilities. PMID:15333692

  1. Quantitative Characterization of the Hemodynamic Environment in Ruptured and Unruptured Brain Aneurysms

    PubMed Central

    Cebral, Juan R.; Mut, Fernando; Weir, Jane; Putman, Christopher

    2011-01-01

    Background and purpose Hemodynamics is thought to play an important role in the mechanisms of aneurysm pathogenesis, progression and rupture. The purpose of this study was to define quantitative measures related to qualitative flow characteristics previously analyzed and to investigate their relationship to aneurysm rupture. Methods The hemodynamic environments in 210 cerebral aneurysms were analyzed using image-based CFD under different flow conditions. Quantitative hemodynamic variables were defined and extracted from the simulation results. A statistical analysis of the relationship to the previous history of aneurysm rupture was performed, and the variability with flow conditions was assessed. Results Ruptured aneurysms were more likely to have larger inflow concentrations, larger maximum wall shear stress (WSS), larger shear concentrations and lower viscous dissipation ratios than unruptured aneurysms. Areas under low WSS and measures of abnormally low shear force distributions of ruptured and unruptured aneurysms were not statistically different. Although the values of hemodynamic quantities changed with different flow conditions, the statistical differences or ratios between their mean values over the ruptured and unruptured groups were maintained, for both pulsatile and steady flows. Conclusions Concentrated inflow streams and WSS distributions with elevated levels of maximal WSS and low aneurysmal viscous dissipation are statistically associated with a clinical history of prior aneurysm rupture. In contrast, the area and total viscous shear force applied in the aneurysm region subjected to abnormally low WSS levels are not. This study highlights the potential for image-based CFD for investigating aneurysm evolution mechanisms and for clinical assessment of aneurysm risks. PMID:21127144

  2. The AAA-ATPase NVL2 is a telomerase component essential for holoenzyme assembly

    SciTech Connect

    Her, Joonyoung; Chung, In Kwon

    2012-01-20

    Highlights: Black-Right-Pointing-Pointer Identification of the AAA-ATPase NVL2 as a novel hTERT-interacting protein. Black-Right-Pointing-Pointer NVL2 associates with catalytically active telomerase via an interaction with hTERT. Black-Right-Pointing-Pointer NVL2 is a telomerase component essential for holoenzyme assembly. Black-Right-Pointing-Pointer ATP-binding activity of NVL2 is required for hTERT binding and telomerase assembly. -- Abstract: Continued cell proliferation requires telomerase to maintain functional telomeres that are essential for chromosome integrity. Although the core enzyme includes a telomerase reverse transcriptase (TERT) and a telomerase RNA component (TERC), a number of auxiliary proteins have been identified to regulate telomerase assembly, localization, and enzymatic activity. Here we describe the characterization of the AAA-ATPase NVL2 as a novel hTERT-interacting protein. NVL2 interacts and co-localizes with hTERT in the nucleolus. NLV2 is also found in association with catalytically competent telomerase in cell lysates through an interaction with hTERT. Depletion of endogenous NVL2 by small interfering RNA led to a decrease in hTERT without affecting the steady-state levels of hTERT mRNA, thereby reducing telomerase activity, suggesting that NVL2 is an essential component of the telomerase holoenzyme. We also found that ATP-binding activity of NVL2 is required for hTERT binding as well as telomerase assembly. Our findings suggest that NVL2, in addition to its role in ribosome biosynthesis, is essential for telomerase biogenesis and provides an alternative approach for inhibiting telomerase activity in cancer.

  3. Endosomal transport function in yeast requires a novel AAA-type ATPase, Vps4p.

    PubMed Central

    Babst, M; Sato, T K; Banta, L M; Emr, S D

    1997-01-01

    In a late-Golgi compartment of the yeast Saccharomyces cerevisiae, vacuolar proteins such as carboxypeptidase Y (CPY) are actively sorted away from the secretory pathway and transported to the vacuole via a pre-vacuolar, endosome-like intermediate. The vacuolar protein sorting (vps) mutant vps4 accumulates vacuolar, endocytic and late-Golgi markers in an aberrant multilamellar pre-vacuolar compartment. The VPS4 gene has been cloned and found to encode a 48 kDa protein which belongs to the protein family of AAA-type ATPases. The Vps4 protein was purified and shown to exhibit an N-ethylmaleimide-sensitive ATPase activity. A single amino acid change within the AAA motif of Vps4p yielded a protein that lacked ATPase activity and did not complement the protein sorting or morphological defects of the vps4 delta1 mutant. Indeed, when expressed at normal levels in wild-type cells, the mutant vps4 gene acted as a dominant-negative allele. The phenotypic characterization of a temperature-sensitive vps4 allele showed that the immediate consequence of loss of Vps4p function is a defect in vacuolar protein delivery. In this mutant, precursor CPY was not secreted but instead accumulated in an intracellular compartment, presumably the pre-vacuolar endosome. Electron microscopy revealed that upon temperature shift, exaggerated stacks of curved cisternal membranes (aberrant endosome) also accumulated in the vps4ts mutant. Based on these and other observations, we propose that Vps4p function is required for efficient transport out of the pre-vacuolar endosome. PMID:9155008

  4. Pareto front analysis of 6 and 15 MV dynamic IMRT for lung cancer using pencil beam, AAA and Monte Carlo

    NASA Astrophysics Data System (ADS)

    Ottosson, R. O.; Karlsson, A.; Behrens, C. F.

    2010-08-01

    The pencil beam dose calculation method is frequently used in modern radiation therapy treatment planning regardless of the fact that it is documented inaccurately for cases involving large density variations. The inaccuracies are larger for higher beam energies. As a result, low energy beams are conventionally used for lung treatments. The aim of this study was to analyze the advantages and disadvantages of dynamic IMRT treatment planning for high and low photon energy in order to assess if deviating from the conventional low energy approach could be favorable in some cases. Furthermore, the influence of motion on the dose distribution was investigated. Four non-small cell lung cancer cases were selected for this study. Inverse planning was conducted using Varian Eclipse. A total number of 31 dynamic IMRT plans, distributed amongst the four cases, were created ranging from PTV conformity weighted to normal tissue sparing weighted. All optimized treatment plans were calculated using three different calculation algorithms (PBC, AAA and MC). In order to study the influence of motion, two virtual lung phantoms were created. The idea was to mimic two different situations: one where the GTV is located centrally in the PTV and another where the GTV was close to the edge of the PTV. PBC is in poor agreement with MC and AAA for all cases and treatment plans. AAA overestimates the dose, compared to MC. This effect is more pronounced for 15 than 6 MV. AAA and MC both predict similar perturbations in dose distributions when moving the GTV to the edge of the PTV. PBC, however, predicts results contradicting those of AAA and MC. This study shows that PB-based dose calculation algorithms are clinically insufficient for patient geometries involving large density inhomogeneities. AAA is in much better agreement with MC, but even a small overestimation of the dose level by the algorithm might lead to a large part of the PTV being underdosed. It is advisable to use low energy as a

  5. Pareto front analysis of 6 and 15 MV dynamic IMRT for lung cancer using pencil beam, AAA and Monte Carlo.

    PubMed

    Ottosson, R O; Karlsson, A; Behrens, C F

    2010-08-21

    The pencil beam dose calculation method is frequently used in modern radiation therapy treatment planning regardless of the fact that it is documented inaccurately for cases involving large density variations. The inaccuracies are larger for higher beam energies. As a result, low energy beams are conventionally used for lung treatments. The aim of this study was to analyze the advantages and disadvantages of dynamic IMRT treatment planning for high and low photon energy in order to assess if deviating from the conventional low energy approach could be favorable in some cases. Furthermore, the influence of motion on the dose distribution was investigated. Four non-small cell lung cancer cases were selected for this study. Inverse planning was conducted using Varian Eclipse. A total number of 31 dynamic IMRT plans, distributed amongst the four cases, were created ranging from PTV conformity weighted to normal tissue sparing weighted. All optimized treatment plans were calculated using three different calculation algorithms (PBC, AAA and MC). In order to study the influence of motion, two virtual lung phantoms were created. The idea was to mimic two different situations: one where the GTV is located centrally in the PTV and another where the GTV was close to the edge of the PTV. PBC is in poor agreement with MC and AAA for all cases and treatment plans. AAA overestimates the dose, compared to MC. This effect is more pronounced for 15 than 6 MV. AAA and MC both predict similar perturbations in dose distributions when moving the GTV to the edge of the PTV. PBC, however, predicts results contradicting those of AAA and MC. This study shows that PB-based dose calculation algorithms are clinically insufficient for patient geometries involving large density inhomogeneities. AAA is in much better agreement with MC, but even a small overestimation of the dose level by the algorithm might lead to a large part of the PTV being underdosed. It is advisable to use low energy as a

  6. Atriocaval Rupture After Right Atrial Isthmus Ablation for Atrial Flutter.

    PubMed

    Vloka, Caroline; Nelson, Daniel W; Wetherbee, Jule

    2016-06-01

    A patient with symptomatic typical atrial flutter (AFL) underwent right atrial isthmus ablation with an 8-mm catheter. Eight months later, his typical AFL recurred. Ten months later, he underwent a repeat right atrial isthmus ablation with an irrigated tip catheter and an 8-mm tip catheter. Six weeks after his second procedure, while performing intense sprint intervals on a treadmill, he developed an abrupt onset of chest pain, hypotension, and cardiac tamponade. He underwent emergency surgery to repair an atriocaval rupture and has done well since. Our report suggests that an association of multiple radiofrequency ablations with increased risk for delayed atriocaval rupture occurring 1 to 3 months after ablation. In conclusion, although patients generally were advised to limit exercise for 1 to 2 weeks after AFL ablation procedures in the past, it may be prudent to avoid intense exercise for at least 3 months after procedure. PMID:27112285

  7. Hyperhomocysteinaemia is an independent risk factor of abdominal aortic aneurysm in a Chinese Han population

    PubMed Central

    Liu, Jie; Wei Zuo, Shang; Li, Yue; Jia, Xin; Jia, Sen Hao; Zhang, Tao; Xiang Song, Yu; Qi Wei, Ying; Xiong, Jiang; Hua Hu, Yong; Guo, Wei

    2016-01-01

    The associations between hyperhomocysteinaemia (HHcy), methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, and abdominal aortic aneurysm (AAA) remain controversial, with only few studies focused on these associations within the Chinese population. We performed subgroup and interaction analyses in a Chinese Han population to investigate these associations. In all, 155 AAA patients and 310 control subjects were evaluated for serum total homocysteine levels and MTHFR C677T polymorphisms. Multiple logistic regression models were used to evaluate the aforementioned associations. Interaction and stratified analyses were conducted according to age, sex, smoking status, drinking status, and chronic disease histories. The multiple logistic analyses showed a significant association between HHcy and AAA but no significant association between MTHFR C677T polymorphism and AAA. The interaction analysis showed that age and peripheral arterial disease played an interactive role in the association between HHcy and AAA, while drinking status played an interactive role in the association between MTHFR C677T polymorphism and AAA. In conclusion, HHcy is an independent risk factor of AAA in a Chinese Han population, especially in the elderly and peripheral arterial disease subgroups. Longitudinal studies and clinical trials aimed to reduce homocysteine levels are warranted to assess the causal nature of these relationships PMID:26865327

  8. Hyperhomocysteinaemia is an independent risk factor of abdominal aortic aneurysm in a Chinese Han population.

    PubMed

    Liu, Jie; Wei Zuo, Shang; Li, Yue; Jia, Xin; Jia, Sen Hao; Zhang, Tao; Xiang Song, Yu; Qi Wei, Ying; Xiong, Jiang; Hua Hu, Yong; Guo, Wei

    2016-01-01

    The associations between hyperhomocysteinaemia (HHcy), methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, and abdominal aortic aneurysm (AAA) remain controversial, with only few studies focused on these associations within the Chinese population. We performed subgroup and interaction analyses in a Chinese Han population to investigate these associations. In all, 155 AAA patients and 310 control subjects were evaluated for serum total homocysteine levels and MTHFR C677T polymorphisms. Multiple logistic regression models were used to evaluate the aforementioned associations. Interaction and stratified analyses were conducted according to age, sex, smoking status, drinking status, and chronic disease histories. The multiple logistic analyses showed a significant association between HHcy and AAA but no significant association between MTHFR C677T polymorphism and AAA. The interaction analysis showed that age and peripheral arterial disease played an interactive role in the association between HHcy and AAA, while drinking status played an interactive role in the association between MTHFR C677T polymorphism and AAA. In conclusion, HHcy is an independent risk factor of AAA in a Chinese Han population, especially in the elderly and peripheral arterial disease subgroups. Longitudinal studies and clinical trials aimed to reduce homocysteine levels are warranted to assess the causal nature of these relationships. PMID:26865327

  9. [Bilateral bronchial rupture: problems of respiratory management].

    PubMed

    Sztark, F; Thicoïpé, M; Favarel-Garrigues, J F; Velly, J F; Lassié, P

    1995-01-01

    The authors report the case of bilateral bronchial rupture in a 39-year-old multiple trauma patient. During the thoracotomy for right main bronchus repair, a partial left bronchial rupture was recognized because of severe hypoxaemia after left selective intubation. PMID:7486281

  10. Madelung Deformity and Extensor Tendon Rupture.

    PubMed

    Shahcheraghi, Gholam Hossain; Peyman, Maryam; Mozafarian, Kamran

    2015-07-01

    Extensor tendon rupture in chronic Madelung deformity, as a result of tendon attrition on the dislocated distal ulna, is a rare occurrence. It is, however, seen more often in rheumatoid arthritis. There are few case reports in the English-language literature on this issue. We report a case of multiple tendon ruptures in a previously undiagnosed Madelung deformity. PMID:26161772

  11. Simultaneous and spontaneous bilateral quadriceps tendons rupture.

    PubMed

    Celik, Evrim Coşkun; Ozbaydar, Mehmet; Ofluoglu, Demet; Demircay, Emre

    2012-07-01

    Simultaneous and spontaneous bilateral quadriceps tendon rupture is an uncommon injury that is usually seen in association with multiple medical conditions and some medications. We report a case of simultaneous and spontaneous bilateral quadriceps tendon rupture that may be related to the long-term use of a statin. PMID:22561379

  12. Myocardial infarction complicated by ventricular septal rupture.

    PubMed

    Sahjian, Michael; Ventriglia, Rich; Bolton, Lauri

    2012-01-01

    Transporting patients with an ST segment elevation myocardial infarction (STEMI) is a fairly common practice for most critical care transport teams. When a STEMI is complicated by ventricular septal rupture, the care can become more challenging, especially if the rupture is not yet diagnosed. This article describes such a transport and reviews the pathophysiology of the process along with treatment options. PMID:22225564

  13. Fractal avalanche ruptures in biological membranes

    NASA Astrophysics Data System (ADS)

    Gözen, Irep; Dommersnes, Paul; Czolkos, Ilja; Jesorka, Aldo; Lobovkina, Tatsiana; Orwar, Owe

    2010-11-01

    Bilayer membranes envelope cells as well as organelles, and constitute the most ubiquitous biological material found in all branches of the phylogenetic tree. Cell membrane rupture is an important biological process, and substantial rupture rates are found in skeletal and cardiac muscle cells under a mechanical load. Rupture can also be induced by processes such as cell death, and active cell membrane repair mechanisms are essential to preserve cell integrity. Pore formation in cell membranes is also at the heart of many biomedical applications such as in drug, gene and short interfering RNA delivery. Membrane rupture dynamics has been studied in bilayer vesicles under tensile stress, which consistently produce circular pores. We observed very different rupture mechanics in bilayer membranes spreading on solid supports: in one instance fingering instabilities were seen resulting in floral-like pores and in another, the rupture proceeded in a series of rapid avalanches causing fractal membrane fragmentation. The intermittent character of rupture evolution and the broad distribution in avalanche sizes is consistent with crackling-noise dynamics. Such noisy dynamics appear in fracture of solid disordered materials, in dislocation avalanches in plastic deformations and domain wall magnetization avalanches. We also observed similar fractal rupture mechanics in spreading cell membranes.

  14. Spontaneous uterine rupture in the 35th week of gestation after laparoscopic adenomyomectomy

    PubMed Central

    Nagao, Yukari; Osato, Kazuhiro; Kubo, Michiko; Kawamura, Takuya; Ikeda, Tomoaki; Yamawaki, Takaharu

    2016-01-01

    Uterine rupture rarely occurs during pregnancy, but it is a critical situation if so. It is already known that a history of uterine surgeries, such as cesarean section or myomectomy, is a risk factor for uterine rupture. Currently, the laparoscopic adenomyomectomy is a widely performed procedure, but associated risks have not been defined. We observed a case of spontaneous uterine rupture in a patient during the 35th week of gestation, after a laparoscopic adenomyomectomy. A 42-year-old, gravida 2, para 0 woman became pregnant after a laparoscopic adenomyomectomy and her pregnancy was conventional. At a scheduled date in the 35th week of gestation, after combined spinal epidural anesthesia and frequent uterine contractions, a weak pain suddenly ensued. After 13 minutes of uterine contractions, vaginal bleeding was evident. A cesarean section was performed, and the uterine rupture was found in the scar. After a laparoscopic adenomyomectomy, a pregnant uterus can easily rupture by rather weak and short uterine contractions, and is characterized by vaginal bleeding. When uterine bleeding is observed in pregnant women that have a history of adenomyomectomy, one should consider uterine rupture. PMID:26719729

  15. Comparison of the tibial mechanical joint orientation angles in dogs with cranial cruciate ligament rupture

    PubMed Central

    Fuller, Mark C.; Kapatkin, Amy S.; Bruecker, Kenneth A.; Holsworth, Ian G.; Kass, Philip H.; Hayashi, Kei

    2014-01-01

    Use of the tibial mechanical joint orientation angles is now the standard of care for evaluating tibial deformities, although they have not been used to evaluate dogs with cranial cruciate ligament (CrCL) rupture. The objective of this study was to compare the tibial mechanical joint orientation angles and tibial plateau angle (TPA) between dogs with bilateral CrCL rupture (BR) and unilateral CrCL rupture with (UR-SR) and without subsequent contralateral CrCL rupture (UR-w/o-SR) as risk factors for subsequent contralateral CrCL rupture. Twenty dogs (21.7%) were classified as BR, 38 (41.3%) were classified as UR-SR, and 34 (37.0%) were classified as UR-w/o-SR. The tibial mechanical joint orientation angles and TPA, in the range studied (< 35°), were not statistically different for dogs with BR, UR-SR, and UR-w/o-SR, and were not significant risk factors for subsequent contralateral CrCL rupture. PMID:25082991

  16. Uterine rupture in pregnancy: two case reports and review of literature.

    PubMed

    Pontis, A; Prasciolu, C; Litta, P; Angioni, S

    2016-01-01

    Rupture of a gravid uterus is an obstetric emergency. Risks factors include a scarred uterus but also spontaneous rupture of an un- scarred uterus during pregnancy is possible. The authors present two cases of a spontaneous complete uterine rupture during pregnancy. The first case had only a past history of dilatation and curettage for abortion; the second case had a past history of dilatation and curettage for abortion and a monolateral laparoscopic salpingectomy for ectopic pregnancy. They presented with abdominal pain and after ultrasound scan, uterine ruptures were diagnosed. These cases show that there should be a high index of suspicious of uterine rupture in a gravid woman with a history of curettage for the possible presence of misunderstood uterine scar and in women with a past history of salpingectomy with or without corneal resection. Appropriate counseling and close follow-up might help to avoid such obstetrical catastrophes. To provide more insight into the possible risk factors for prelabor uterine rupture in pregnancy, a literature review was performed. PMID:27132437

  17. The effects of barriers on supershear rupture

    NASA Astrophysics Data System (ADS)

    Xu, Jiankuan; Zhang, Zhenguo; Chen, Xiaofei

    2016-07-01

    A barrier may induce a supershear rupture transition in some cases, whereas it may prevent the further propagation of a supershear rupture in other cases. We investigate the effects of a barrier on the supershear rupture propagation on a planar fault in a 3-D half-space. Our results show that the effect of a barrier on supershear is strongly dependent on its size, strength, and location. For larger sizes, shallower buried depths, and relatively higher strengths, the barrier tends to prevent supershear propagation more strongly. When the barrier is located on the free surface and near the critical distance, it prevents the further propagation of supershear rupture. If a barrier is located far from the critical distance, the first supershear daughter crack is slowed down and a new supershear daughter crack is generated after the rupture front passes through the barrier. This mechanism greatly lengthens the supershear transition distance.

  18. Comparison of risk-scoring systems in predicting hospital mortality after abdominal aortic aneurysm repair

    PubMed Central

    Supsamutchai, Chaiyarat; Wilasrusmee, Chumpon; Lertsithichai, Panuwat; Proprom, Napaphat; Kittur, Dilip S

    2008-01-01

    OBJECTIVE: To compare the Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity, Portsmouth adjustment (P-POSSUM), the Hardman index and the Glasgow aneurysm score (GAS) in the prediction of hospital mortality after abdominal aortic aneurysm (AAA) repair. METHODS: Medical charts of 146 AAA patients treated between January 1996 and January 2007 were reviewed. The P-POSSUM, Hardman index and GAS were calculated for each patient. The scores were tested and compared for their discriminatory ability to predict hospital death. RESULTS: Of the 146 patients with ruptured and unruptured AAAs (133 underwent open repair, five underwent extra-anatomical bypass and eight underwent endovascular aneurysm repair), 18 died (12%) after AAA repair. The areas under the receiver operating characteristic curves for the GAS, Hardman index and P-POSSUM for predicting hospital mortality were 0.740, 0.730 and 0.886, respectively. The area under the receiver operating characteristic curve for the P-POSSUM was significantly higher than those of other scores. CONCLUSION: In the present study, the P-POSSUM was the best predictor of hospital mortality for patients undergoing AAA repair. PMID:22477446

  19. Ruptured disc after arthroscopic repositioning in the temporomandibular joint: a retrospective magnetic resonance imaging study.

    PubMed

    Li, Hui; Cai, Xieyi; Yang, Chi; Wang, Shaoyi; Huang, Linjian

    2014-07-01

    Our aim was to explore the incidence of rupture after arthroscopic repositioning of the disc of the temporomandibular joint (TMJ) by reviewing magnetic resonance images (MRI) of the TMJ taken before and after operation, and to investigate correlations retrospectively. We studied 247 patients with anterior disc displacement of the TMJ, and categorised them into 3 groups based on the postoperative MRI. The first group comprised those whose disc ruptured after repositioning, the second those who had a possible rupture of the disc after repositioning, and the third had no rupture of the disc after repositioning. Age, sex, duration of symptoms, maximum incisal mouth opening, whether the anterior disc displacement was unilateral or bilateral, and the Wilkes stage, were included in the analysis. The incidence of rupture (5/247) was 2%. Weak points at the intermediate zone of the disc were found in 4 of the 5 joints. The patients whose discs ruptured were significantly younger than the other 2 groups (p=0.001). There was no statistically significant difference in preoperative duration of symptoms and mouth opening among the groups. The proportions of unilateral and bilateral disc displacement (p=0.047) and Wilkes stage (p=0.027) differed among the 3 groups. The Wilkes stages was significantly more advanced in the ruptured group than in the other 2 groups (p=0.027) with 4/5 being bilateral. The weak point in the intermediate zone of the disc on MRI could be a sign of rupture. Teenagers and young adults with anterior disc displacement without reduction, particularly those in whom it is bilateral, are at a higher risk of a rupture after repositioning of the disc by arthroscopy. PMID:24736122

  20. Do buried-rupture earthquakes trigger less landslides than surface-rupture earthquakes for reverse faults?

    NASA Astrophysics Data System (ADS)

    Xu, Chong

    2014-07-01

    Gorum et al. (2013, Geomorphology 184, 127-138) carried out a study on inventory compilation and statistical analyses of landslides triggered by the 2010 Mw 7.0 Haiti earthquake. They revealed that spatial distribution patterns of these landslides were mainly controlled by complex rupture mechanism and topography. They also suggested that blind-rupture earthquakes trigger fewer landslides than surface-rupture earthquakes on thrust reverse faults. Although a few lines of evidence indicate that buried-rupture earthquakes might trigger fewer landslides than surface-rupture earthquakes on reverse faults, more careful comparisons and analyses indicate that it is not always true. Instead, some cases show that a buried-rupture earthquake can trigger a larger quantity of landslides that are distributed in a larger area, whereas surface-rupture earthquakes can trigger larger but a fewer landslides distributed in a smaller area.

  1. Reverse genetics studies of attenuation of the ca A/AA/6/60 influenza virus: the role of the matrix gene.

    PubMed

    Sweet, T M; Maassab, H F; Herlocher, M L

    2004-11-01

    The matrix (M) gene of influenza virus has been implicated in the attenuation phenotype of the cold adapted (ca) A/AA/6/60 vaccine. Previous studies have evaluated the ca M from A/AA/6/60 in different wild type (wt) virus backgrounds with varying results. In experiments described here, the ca M gene was transfected into the background of its own wt A/AA/6/60 to eliminate the possibility of confounding gene constellation effects. Comparison of the sequence of the wt and the ca A/AA/6/60 revealed one substitution in the nucleotide sequence of M. The molecular techniques of reverse genetics were used to rescue the ca M gene into the virulent wt A/AA/6/60 virus. The selection system used to identify the desired transfectant virus was amantadine resistance, which was introduced into the M2 gene using mutagenesis. The ca A/AA/6/60, the wt A/AA/6/60, a virus which contained wt M and was wt in the remaining seven genes and amantadine resistant (wt/969), a virus which contained the ca M but wt in the other seven genes (ca/969) were all evaluated in mice determine the effect of the ca M. The ca/969 virus was not attenuated in the mouse model when compared to the wt/969 virus, indicating that the ca A/AA/6/60 M does not independently contribute to the attenuation phenotype attributed to the ca A/AA/6/60 vaccine virus. PMID:15511608

  2. Spontaneous rupture of the spleen operated in gynecological unit mistaken for ruptured hemorrhagic ovarian cyst: total splenectomy

    PubMed Central

    Eko, Filbert Eko; Fouelifack, Florent Ymele; de Paul, Elanga Vincent

    2014-01-01

    Spontaneous splenic rupture is always neglected when consulting acute abdominal pains in gynecological emergencies. It constitutes about 1% of all splenic ruptures and can be managed by abstention, surgery or embolization. We present the case of a young lady who was diagnosed of spontaneous rupture during surgery that was mistaken for ruptured hemorrhagic ovarian cyst and finally treated by total splenectomy. The pre-operative work up was absolute for a rupturred hemorrhagic cyst and secondariy for a ruptured ectopic gestation. PMID:25918564

  3. Protective Role of Diabetes Mellitus on Abdominal Aortic Aneurysm Pathogenesis: Myth or Reality?

    PubMed

    Radak, Djordje; Tanaskovic, Slobodan; Katsiki, Niki; Isenovic, Esma R

    2016-01-01

    An inverse association between diabetes mellitus (DM) and abdominal aortic aneurysm (AAA) risk have been reported. Apart from a lower AAA prevalence among patients with vs without DM, there are data showing that DM may exert a protective role on aneurysmal growth in patients with small AAAs, thus decreasing the risk of rupture. As atherosclerosis has almost the same risk factors as aneurysms, the decreased AAA prevalence in patients with DM may indicate that atherosclerosis is an associated feature and not a cause of the aneurysms. Alternatively, DM may be associated with factors that influence AAA formation. In this narrative review, we discuss the inverse association between DM and AAA. We also comment on underlying cellular and genetic pathophysiological mechanisms of DM, AAA and atherosclerosis. The effects of drugs, commonly prescribed in DM patients, on AAA development and growth are also considered. PMID:26022380

  4. Rupture and Migration of an Endovascular Stent in the Brachiocephalic Trunk Causing a Vertebral Steal Syndrome

    SciTech Connect

    Periard, D. Haesler, E.; Hayoz, D.; Von Segesser, L. K.; Qanadli, S. D.

    2008-07-15

    Delayed stent fracture has been observed in many different arteries and may represent a risk factor for restenosis. We describe the case of a delayed rupture of an endovascular brachiocephalic trunk stent. The complete fracture allowed a fragment to migrate distally and tilt, resulting in a hemodynamic pattern similar to that of a prevertebral stenosis with complete inversion of the homolateral vertebral blood flow. The induced vertebral steal syndrome as well as the risk of cerebral embolism was corrected by an aortobrachiocephalic bypass and resection of the ruptured stent.

  5. Proximal humerus shaft fracture after pectoralis major tendon rupture repair.

    PubMed

    Silverstein, Jeff A; Goldberg, Ben; Wolin, Preston

    2011-06-01

    Surgical repair of a complete pectoralis major tendon rupture at the humeral insertion has superior results compared to nonoperative treatment. To our knowledge, a proximal humerus shaft fracture occurring at the site of the bone trough and cortical drill holes after a pectoralis major tendon rupture repair has not been reported in the literature.A 45-year-old man sustained an acute left pectoralis major tendon rupture at the humeral insertion while performing a bench press maneuver. He underwent acute surgical repair. Approximately 8 weeks postoperatively, the patient fell from a standing height and sustained a proximal humerus shaft fracture through the repair site at the bone trough. Three days after the fracture, the patient underwent open reduction and internal fixation of the proximal humerus shaft fracture and exploration of the pectoralis major tendon repair. The fracture was found to be at the level of the repair site, and the pectoralis major tendon was completely intact to the distal fragment. The fracture healed uneventfully, and the patient regained full motion and strength of his extremity with no limitations.Any type of surgical fixation that creates a hole in the humerus or decreases the cross-sectional area such as a bone trough creates a stress riser. Patients undergoing pectoralis tendon repair that involves violating the humerus with a bone trough or hole have a slight risk of postoperative humerus fracture, especially if sustaining an early traumatic event such as a fall. PMID:21667914

  6. Miniopen Repair of Ruptured Achilles Tendon in Diabetic Patients

    PubMed Central

    2014-01-01

    Background. Acute degenerative Achilles tendons ruptures may be managed either operatively or nonoperatively with the superiority of the operative treatment in reducing the risk of rerupture. Acute rupture of Achilles tendon is commonly seen in diabetic patients. Open techniques for Achilles tendon repair have been associated with significant complications as deep infection and wound-related problems. Patients and Methods. Thirteen type II diabetic patients with acute degenerative rupture of the Achilles tendon were managed by miniopen repair augmented by peroneus brevis tendon. Results. All repairs healed successfully. The patients were able to return to preinjury level of activity after a mean of 5 months. The mean ATRS score improved from 15.1 preoperatively to 74.8 postoperatively. The mean Leppilahti ankle score was 59.6. Three patients suffered from superficial wound infection which was successfully managed. However, no patients suffered any major complications such as DVT, deep infection, or reruptures during the period of the study. Conclusion. Repair of acute degenerative tear of the Achilles tendon with peroneus brevis tendon augmentation could be successfully performed through a miniopen technique with minimization of wound complications in diabetic patients. PMID:27437478

  7. 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

  8. Ruptured rudimentary horn pregnancy at sixteen weeks.

    PubMed

    Zeqiri, Fehmi; Paçarada, Myrvete; Kongjeli, Niltene; Zeqiri, Vlora; Kongjeli, Gyltene; Krasniqi, Burim

    2010-01-01

    Pregnancy in a non-communicating rudimentary horn is very difficult to diagnose before it ruptures, leading to life -threatening intraperitoneal hemorrhage. A 22-year-old second gravida patient presented at the Emergency Center of the University Clinical Center of Kosova with a 16-week history of amenorrhea and acute onset of severe abdominal pain. She was resuscitated and taken for an emergency laparotomy under general anesthesia. Intraoperatively, there was a massive hemoperitoneum with a ruptured right rudimentary horn Given their rarity, ruptured rudimentary horn pregnancies are of interest. PMID:24591927

  9. Misdiagnosed Chest Pain: Spontaneous Esophageal Rupture

    PubMed Central

    Inci, Sinan; Gundogdu, Fuat; Gungor, Hasan; Arslan, Sakir; Turkyilmaz, Atila; Eroglu, Atila

    2013-01-01

    Chest pain is one of themost common complaints expressed by patients presenting to the emergency department, and any initial evaluation should always consider life-threatening causes. Esophageal rupture is a serious condition with a highmortality rate. If diagnosed, successful therapy depends on the size of the rupture and the time elapsed between rupture and diagnosis.We report on a 41-year-old woman who presented to the emergency department complaining of left-sided chest pain for two hours. PMID:27122690

  10. Creep-rupture reliability analysis

    NASA Technical Reports Server (NTRS)

    Peralta-Duran, A.; Wirsching, P. H.

    1984-01-01

    A probabilistic approach to the correlation and extrapolation of creep-rupture data is presented. Time temperature parameters (TTP) are used to correlate the data, and an analytical expression for the master curve is developed. The expression provides a simple model for the statistical distribution of strength and fits neatly into a probabilistic design format. The analysis focuses on the Larson-Miller and on the Manson-Haferd parameters, but it can be applied to any of the TTP's. A method is developed for evaluating material dependent constants for TTP's. It is shown that optimized constants can provide a significant improvement in the correlation of the data, thereby reducing modelling error. Attempts were made to quantify the performance of the proposed method in predicting long term behavior. Uncertainty in predicting long term behavior from short term tests was derived for several sets of data. Examples are presented which illustrate the theory and demonstrate the application of state of the art reliability methods to the design of components under creep.

  11. Creep-rupture reliability analysis

    NASA Technical Reports Server (NTRS)

    Peralta-Duran, A.; Wirsching, P. H.

    1985-01-01

    A probabilistic approach to the correlation and extrapolation of creep-rupture data is presented. Time temperature parameters (TTP) are used to correlate the data, and an analytical expression for the master curve is developed. The expression provides a simple model for the statistical distribution of strength and fits neatly into a probabilistic design format. The analysis focuses on the Larson-Miller and on the Manson-Haferd parameters, but it can be applied to any of the TTP's. A method is developed for evaluating material dependent constants for TTP's. It is shown that optimized constants can provide a significant improvement in the correlation of the data, thereby reducing modelling error. Attempts were made to quantify the performance of the proposed method in predicting long term behavior. Uncertainty in predicting long term behavior from short term tests was derived for several sets of data. Examples are presented which illustrate the theory and demonstrate the application of state of the art reliability methods to the design of components under creep.

  12. Vortex Imprints at the Wall, But Not in the Bulk, Distinguish Ruptured from Unruptured Intracranial Aneurysms

    NASA Astrophysics Data System (ADS)

    Varble, Nicole; Meng, Hui

    2015-11-01

    Intracranial aneurysms affect 3% of the population. Risk stratification of aneurysms is important, as rupture often leads to death or permanent disability. Image-based CFD analyses of patient-specific aneurysms have identified low and oscillatory wall shear stress to predict rupture. These stresses are sensed biologically at the luminal wall, but the flow dynamics related to aneurysm rupture requires further understanding. We have conducted two studies: one examines vortex dynamics, and the other, high frequency flow fluctuations in patient-specific aneurysms. In the first study, based on Q-criterion vortex identification, we developed two measures to quantify regions within the aneurysm where rotational flow is dominate: the ratio of volume or surface area where Q >0 vs. the total aneurysmal volume or surface area, respectively termed volume vortex fraction (VVF) and surface vortex fraction (SVF). Statistical analysis of 204 aneurysms shows that SVF, but not VVF, distinguishes ruptured from unruptured aneurysms, suggesting that once again, the local flow patterns on the wall is directly relevant to rupture. In the second study, high-resolution CFD (high spatial and temporal resolutions and second-order discretization schemes) on 56 middle cerebral artery aneurysms shows the presence of temporal fluctuations in 8 aneurysms, but such flow instability bears no correlation with rupture. Support for this work was partially provided by NIH grant (R01 NS091075-01) and a grant from Toshiba Medical Systems Corp.

  13. Changing Views of the Biomechanics of Vulnerable Plaque Rupture, a Review

    PubMed Central

    Cardoso, Luis; Weinbaum, Sheldon

    2013-01-01

    This review examines changing perspectives on the biomechanics of vulnerable plaque rupture over the past 25 years from the first FEA showing that the presence of a lipid pool significantly increases the local tissue stress in the atheroma cap to the latest imaging and 3D FEA studies revealing numerous microcalcifications in the cap proper and a new paradigm for cap rupture. The first part of the review summarizes studies describing the role of the fibrous cap thickness, tissue properties and lesion geometry as main determinants of the risk of rupture. Advantages and limitations of current imaging technologies for assessment of vulnerable plaques are also discussed. However, the basic paradoxes as to why ruptures frequently did not coincide with location of PCS and why caps > 65 μm thickness could rupture at tissue stresses significantly below the 300 kPa critical threshold still remained unresolved. The second part of the review describes recent studies in the role of microcalcifications, their origin, shape and clustering in explaining these unresolved issues including the actual mechanism of rupture due to the explosive growth of tiny voids (cavitation) in locals regions of high stress concentration between closely spaced microinclusions oriented along their tensile axis. PMID:23842694

  14. Uterine rupture revisited: Predisposing factors, clinical features, management and outcomes from a tertiary care center in Turkey

    PubMed Central

    Turgut, Abdulkadir; Ozler, Ali; Siddik Evsen, Mehmet; Ender Soydinc, Hatice; Yaman Goruk, Neval; Karacor, Talip; Gul, Talip

    2013-01-01

    Objective: To determine the predisposing factors, modes of clinical presentation, management modalities and fetomaternal outcomes of uterine rupture cases at a tertiary care center in Turkey. Methodology: A 14-year retrospective analysis of 61 gravid (>20 weeks of gestation) uterine rupture cases between January 1998 to March 2012 was carried out. Results: The incidence of ruptured uteri was calculated to be 0.116%. Persistence for vaginal delivery after cesarean was the most common cause of uterine rupture (31.1%). Ablatio placenta was the most common co-existent obstetric pathology (4.9%). Bleeding was the main symptom at presentation (44.3%) and complete type of uterine rupture (93.4%) was more likely to occur. Isthmus was the most vulnerable part of uterus (39.3%) for rupture. The longer the interval between rupture and surgical intervention, the longer the duration of hospitalization was. Older patients with increased number of previous pregnancies were likely to have longer hospitalization periods. Conclusion: Rupture of gravid uterus brings about potentially hazardous risks. Regular antenatal care, hospital deliveries and vigilance during labor with quick referral to a well-equipped center may reduce the incidence of this condition. PMID:24353622

  15. CODAS Syndrome Is Associated with Mutations of LONP1, Encoding Mitochondrial AAA+ Lon Protease

    PubMed Central

    Strauss, Kevin A.; Jinks, Robert N.; Puffenberger, Erik G.; Venkatesh, Sundararajan; Singh, Kamalendra; Cheng, Iteen; Mikita, Natalie; Thilagavathi, Jayapalraja; Lee, Jae; Sarafianos, Stefan; Benkert, Abigail; Koehler, Alanna; Zhu, Anni; Trovillion, Victoria; McGlincy, Madeleine; Morlet, Thierry; Deardorff, Matthew; Innes, A. Micheil; Prasad, Chitra; Chudley, Albert E.; Lee, Irene Nga Wing; Suzuki, Carolyn K.

    2015-01-01

    CODAS syndrome is a multi-system developmental disorder characterized by cerebral, ocular, dental, auricular, and skeletal anomalies. Using whole-exome and Sanger sequencing, we identified four LONP1 mutations inherited as homozygous or compound-heterozygous combinations among ten individuals with CODAS syndrome. The individuals come from three different ancestral backgrounds (Amish-Swiss from United States, n = 8; Mennonite-German from Canada, n = 1; mixed European from Canada, n = 1). LONP1 encodes Lon protease, a homohexameric enzyme that mediates protein quality control, respiratory-complex assembly, gene expression, and stress responses in mitochondria. All four pathogenic amino acid substitutions cluster within the AAA+ domain at residues near the ATP-binding pocket. In biochemical assays, pathogenic Lon proteins show substrate-specific defects in ATP-dependent proteolysis. When expressed recombinantly in cells, all altered Lon proteins localize to mitochondria. The Old Order Amish Lon variant (LONP1 c.2161C>G[p.Arg721Gly]) homo-oligomerizes poorly in vitro. Lymphoblastoid cell lines generated from affected children have (1) swollen mitochondria with electron-dense inclusions and abnormal inner-membrane morphology; (2) aggregated MT-CO2, the mtDNA-encoded subunit II of cytochrome c oxidase; and (3) reduced spare respiratory capacity, leading to impaired mitochondrial proteostasis and function. CODAS syndrome is a distinct, autosomal-recessive, developmental disorder associated with dysfunction of the mitochondrial Lon protease. PMID:25574826

  16. Proteolytic processing of Atg32 by the mitochondrial i-AAA protease Yme1 regulates mitophagy.

    PubMed

    Wang, Ke; Jin, Meiyan; Liu, Xu; Klionsky, Daniel J

    2013-11-01

    Mitophagy, the autophagic removal of mitochondria, occurs through a highly selective mechanism. In the yeast Saccharomyces cerevisiae, the mitochondrial outer membrane protein Atg32 confers selectivity for mitochondria sequestration as a cargo by the autophagic machinery through its interaction with Atg11, a scaffold protein for selective types of autophagy. The activity of mitophagy in vivo must be tightly regulated considering that mitochondria are essential organelles that produce most of the cellular energy, but also generate reactive oxygen species that can be harmful to cell physiology. We found that Atg32 was proteolytically processed at its C terminus upon mitophagy induction. Adding an epitope tag to the C terminus of Atg32 interfered with its processing and caused a mitophagy defect, suggesting the processing is required for efficient mitophagy. Furthermore, we determined that the mitochondrial i-AAA protease Yme1 mediated Atg32 processing and was required for mitophagy. Finally, we found that the interaction between Atg32 and Atg11 was significantly weakened in yme1∆ cells. We propose that the processing of Atg32 by Yme1 acts as an important regulatory mechanism of cellular mitophagy activity. PMID:24025448

  17. Structural Basis for the Magnesium-Dependent Activation and Hexamerization of the Lon AAA+ Protease.

    PubMed

    Su, Shih-Chieh; Lin, Chien-Chu; Tai, Hui-Chung; Chang, Mu-Yueh; Ho, Meng-Ru; Babu, C Satheesan; Liao, Jiahn-Haur; Wu, Shih-Hsiung; Chang, Yuan-Chih; Lim, Carmay; Chang, Chung-I

    2016-05-01

    The Lon AAA+ protease (LonA) plays important roles in protein homeostasis and regulation of diverse biological processes. LonA behaves as a homomeric hexamer in the presence of magnesium (Mg(2+)) and performs ATP-dependent proteolysis. However, it is also found that LonA can carry out Mg(2+)-dependent degradation of unfolded protein substrate in an ATP-independent manner. Here we show that in the presence of Mg(2+) LonA forms a non-secluded hexameric barrel with prominent openings, which explains why Mg(2+)-activated LonA can operate as a diffusion-based chambered protease to degrade unstructured protein and peptide substrates efficiently in the absence of ATP. A 1.85 Å crystal structure of Mg(2+)-activated protease domain reveals Mg(2+)-dependent remodeling of a substrate-binding loop and a potential metal-binding site near the Ser-Lys catalytic dyad, supported by biophysical binding assays and molecular dynamics simulations. Together, these findings reveal the specific roles of Mg(2+) in the molecular assembly and activation of LonA. PMID:27041593

  18. The AAA ATPase VPS4/SKD1 regulates endosomal cholesterol trafficking independently of ESCRT-III.

    PubMed

    Du, Ximing; Kazim, Abdulla S; Dawes, Ian W; Brown, Andrew J; Yang, Hongyuan

    2013-01-01

    The exit of low-density lipoprotein derived cholesterol (LDL-C) from late endosomes (LE)/lysosomes (Ly) is mediated by Niemann-Pick C1 (NPC1), a multipass integral membrane protein on the limiting membranes of LE/Ly, and by NPC2, a cholesterol-binding protein in the lumen of LE/Ly. NPC2 delivers cholesterol to the N-terminal domain of NPC1, which is believed to insert cholesterol into the limiting membrane for subsequent transport to other subcellular organelles. Few cytoplasmic factors have been identified to govern cholesterol efflux from LE/Ly, and much less is known about the underlying molecular mechanisms. Here we establish VPS4, an AAA ATPase that has a well-established role in disassembling the ESCRT (endosomal sorting complex required for transport)-III polymer, as an important regulator of endosomal cholesterol transport. Knocking down VPS4 in HeLa cells resulted in prominent accumulation of LDL-C in LE/Ly, and disrupted cholesterol homeostatic responses at the endoplasmic reticulum. The level and localization of NPC1 and NPC2 appeared to be normal in VPS4 knockdown cells. Importantly, depleting any of the ESCRT-III components did not exert a significant effect on endosomal cholesterol transport. Our results thus identify an important cytoplasmic regulator of endosomal cholesterol trafficking and represent the first functional separation of VPS4 from ESCRT-III. PMID:23009658

  19. The AAA-type ATPase AtSKD1 contributes to vacuolar maintenance of Arabidopsis thaliana.

    PubMed

    Shahriari, Mojgan; Keshavaiah, Channa; Scheuring, David; Sabovljevic, Aneta; Pimpl, Peter; Häusler, Rainer E; Hülskamp, Martin; Schellmann, Swen

    2010-10-01

    The vacuole is the most prominent organelle of plant cells. Despite its importance for many physiological and developmental aspects of plant life, little is known about its biogenesis and maintenance. Here we show that Arabidopsis plants expressing a dominant-negative version of the AAA (ATPase associated with various cellular activities) ATPase AtSKD1 (SUPPRESSOR OF K+ TRANSPORT GROWTH DEFECT1) under the control of the trichome-specific GLABRA2 (GL2) promoter exhibit normal vacuolar development in early stages of trichome development. Shortly after its formation, however, the large central vacuole is fragmented and finally disappears completely. Secretion assays with amylase fused to the vacuolar sorting signal of Sporamin show that dominant-negative AtSKD1 inhibits vacuolar trafficking of the reporter that is instead secreted. In addition, trichomes expressing dominant-negative AtSKD1 frequently contain multiple nuclei. Our results suggest that AtSKD1 contributes to vacuolar protein trafficking and thereby to the maintenance of the large central vacuole of plant cells, and might play a role in cell-cycle regulation. PMID:20663085

  20. Maintenance of mitochondrial genome distribution by mitochondrial AAA+ protein ClpX.

    PubMed

    Kasashima, Katsumi; Sumitani, Megumi; Endo, Hitoshi

    2012-11-01

    The segregation of mitochondrial DNA (mtDNA) is important for the maintenance and transmission of the genome between generations. Recently, we clarified that human mitochondrial transcription factor A (TFAM) is required for equal distribution and symmetric segregation of mtDNA in cultured cells; however, the molecular mechanism involved is largely unknown. ClpX is an ATPase associated with various cellular activities (AAA+) proteins that localize to the mitochondrial matrix and is suggested to associate with mtDNA. In this study, we found that RNAi-mediated knockdown of ClpX in HeLa cells resulted in enlarged mtDNA nucleoids, which is very similar to that observed in TFAM-knockdown cells in several properties. The expression of TFAM protein was not significantly reduced in ClpX-knockdown cells. However, the enlarged mtDNA nucleoids caused by ClpX-knockdown were suppressed by overexpression of recombinant TFAM and the phenotype was not observed in knockdown with ClpP, a protease subunit of ClpXP. Endogenous ClpX and TFAM exist in close vicinity, and ClpX enhanced DNA-binding activity of TFAM in vitro. These results suggest that human ClpX, a novel mtDNA regulator, maintains mtDNA nucleoid distribution through TFAM function as a chaperone rather than as a protease and its involvement in mtDNA segregation. PMID:22841477

  1. Design of a low-[beta-2]-gap spoke resonator for the AAA Project

    SciTech Connect

    Krawczyk, F. L.; Garnett, R. W.; La Fave, R. P.; Kelley, J. P.; Schrage, D. L.; Tajima, T.; Roybal, P. L.

    2001-01-01

    In this paper, we present the electromagnetic and structural design of a low-b superconducting spoke resonator for a beam-test in the Low Energy Demonstration Accelerator (LEDA). This test is part of the Advanced Accelerator Applications (AAA) project. Recently, the use of superconducting resonators for energies greater than 6.7 MeV has been approved. The beam test will use the lowest-b resonator from this accelerator design. The choices of the cavity dimensions are driven by its use immediately downstream of the LEDA Radio-Frequency Quadrupole (RFQ). The frequency is 350 MHz. The length corresponds to a geometric b (bg) of 0.175. Our design approach has been to carry out an integrated RF and mechanical design from the start. The final cavity is well understood in terms of RF and mechanical properties. The RF properties, like Q, R/Q, peak surface fields and acceleration efficiency are very reasonable for such a low-b structure. The design also includes power coupler, vacuum and pick-up ports and their influences. The mechanical design added tuning sensitivities, tuning forces, stiffening schemes and the understanding of stresses under various load conditions.

  2. Subunit Interactions and Cooperativity in the Microtubule-severing AAA ATPase Spastin*

    PubMed Central

    Eckert, Thomas; Link, Susanne; Le, Doan Tuong-Van; Sobczak, Jean-Philippe; Gieseke, Anja; Richter, Klaus; Woehlke, Günther

    2012-01-01

    Spastin is a hexameric ring AAA ATPase that severs microtubules. To see whether the ring complex funnels the energy of multiple ATP hydrolysis events to the site of mechanical action, we investigate here the cooperativity of spastin. Several lines of evidence indicate that interactions among two subunits dominate the cooperative behavior: (i) the ATPase activity shows a sigmoidal dependence on the ATP concentration; (ii) ATPγS displays a mixed-inhibition behavior for normal ATP turnover; and (iii) inactive mutant subunits inhibit the activity of spastin in a hyperbolic dependence, characteristic for two interacting species. A quantitative model based on neighbor interactions fits mutant titration experiments well, suggesting that each subunit is mainly influenced by one of its neighbors. These observations are relevant for patients suffering from SPG4-type hereditary spastic paraplegia and explain why single amino acid exchanges lead to a dominant negative phenotype. In severing assays, wild type spastin is even more sensitive toward the presence of inactive mutants than in enzymatic assays, suggesting a weak coupling of ATPase and severing activity. PMID:22637577

  3. AAA+ Chaperone ClpX Regulates Dynamics of Prokaryotic Cytoskeletal Protein FtsZ*

    PubMed Central

    Sugimoto, Shinya; Yamanaka, Kunitoshi; Nishikori, Shingo; Miyagi, Atsushi; Ando, Toshio; Ogura, Teru

    2010-01-01

    AAA+ chaperone ClpX has been suggested to be a modulator of prokaryotic cytoskeletal protein FtsZ, but the details of recognition and remodeling of FtsZ by ClpX are largely unknown. In this study, we have extensively investigated the nature of FtsZ polymers and mechanisms of ClpX-regulated FtsZ polymer dynamics. We found that FtsZ polymerization is inhibited by ClpX in an ATP-independent manner and that the N-terminal domain of ClpX plays a crucial role for the inhibition of FtsZ polymerization. Single molecule analysis with high speed atomic force microscopy directly revealed that FtsZ polymer is in a dynamic equilibrium between polymerization and depolymerization on a time scale of several seconds. ClpX disassembles FtsZ polymers presumably by blocking reassembly of FtsZ. Furthermore, Escherichia coli cells overproducing ClpX and N-terminal domain of ClpX show filamentous morphology with abnormal localization of FtsZ. These data together suggest that ClpX modulates FtsZ polymer dynamics in an ATP-independent fashion, which is achieved by interaction between the N-terminal domain of ClpX and FtsZ monomers or oligomers. PMID:20022957

  4. Critical clamp loader processing by an essential AAA+ protease in Caulobacter crescentus

    PubMed Central

    Vass, Robert H.; Chien, Peter

    2013-01-01

    Chromosome replication relies on sliding clamps that are loaded by energy-dependent complexes. In Escherichia coli, the ATP-binding clamp loader subunit DnaX exists as both long (τ) and short (γ) forms generated through programmed translational frameshifting, but the need for both forms is unclear. Here, we show that in Caulobacter crescentus, DnaX isoforms are unexpectedly generated through partial proteolysis by the AAA+ protease casein lytic proteinase (Clp) XP. We find that the normally processive ClpXP protease partially degrades DnaX to produce stable fragments upon encountering a glycine-rich region adjacent to a structured domain. Increasing the sequence complexity of this region prevents partial proteolysis and generates a τ-only form of DnaX in vivo that is unable to support viability on its own. Growth is restored when γ is provided in trans, but these strains are more sensitive to DNA damage compared with strains that can generate γ through proteolysis. Our work reveals an unexpected mode of partial processing by the ClpXP protease to generate DnaX isoforms, demonstrates that both τ and γ forms of DnaX are required for Caulobacter viability, and identifies a role for clamp loader diversity in responding to DNA damage. The conservation of distinct DnaX isoforms throughout bacteria despite fundamentally different mechanisms for producing them suggests there may be a conserved need for alternate clamp loader complexes during DNA damaging conditions. PMID:24145408

  5. The Archaeal Proteasome Is Regulated by a Network of AAA ATPases*

    PubMed Central

    Forouzan, Dara; Ammelburg, Moritz; Hobel, Cedric F.; Ströh, Luisa J.; Sessler, Nicole; Martin, Jörg; Lupas, Andrei N.

    2012-01-01

    The proteasome is the central machinery for targeted protein degradation in archaea, Actinobacteria, and eukaryotes. In its basic form, it consists of a regulatory ATPase complex and a proteolytic core particle. The interaction between the two is governed by an HbYX motif (where Hb is a hydrophobic residue, Y is tyrosine, and X is any amino acid) at the C terminus of the ATPase subunits, which stimulates gate opening of the proteasomal α-subunits. In archaea, the proteasome-interacting motif is not only found in canonical proteasome-activating nucleotidases of the PAN/ARC/Rpt group, which are absent in major archaeal lineages, but also in proteins of the CDC48/p97/VAT and AMA groups, suggesting a regulatory network of proteasomal ATPases. Indeed, Thermoplasma acidophilum, which lacks PAN, encodes one CDC48 protein that interacts with the 20S proteasome and activates the degradation of model substrates. In contrast, Methanosarcina mazei contains seven AAA proteins, five of which, both PAN proteins, two out of three CDC48 proteins, and the AMA protein, function as proteasomal gatekeepers. The prevalent presence of multiple, distinct proteasomal ATPases in archaea thus results in a network of regulatory ATPases that may widen the substrate spectrum of proteasomal protein degradation. PMID:22992741

  6. ATP-binding sites in brain p97/VCP (valosin-containing protein), a multifunctional AAA ATPase.

    PubMed Central

    Zalk, Ran; Shoshan-Barmatz, Varda

    2003-01-01

    VCP (valosin-containing protein) or p97 is a member of the AAA family (ATPases associated with a variety of cellular activities family), a diverse group of proteins sharing a key conserved AAA module containing duplicate putative ATP-binding sites. Although the functions of the AAA family are related to their putative ATP-binding sites, the binding of ATP to these sites has not yet been demonstrated. In the present study, the ATP-binding site(s) of brain VCP was characterized using the photoreactive ATP analogue, BzATP [3'- O -(4-benzoylbenzoyl)ATP]. Photo-activation of Bz-[alpha-(32)P]ATP resulted in its covalent binding to a 97-kDa purified soluble or membrane-associated protein, identified by amino acid sequencing as VCP. Bz-[alpha-(32)P]ATP covalently bound to the purified homo-hexameric VCP with an apparent high affinity (74-111 nM). A molar stoichiometry of 2.23+/-0.14 BzATP bound per homo-hexameric VCP (n =6) was determined using different methods for analysis of radiolabelling and protein determination. Nucleotides inhibited the binding of Bz-[alpha-(32)P]ATP to VCP with the following efficiency: BzATP>ATP>ADP>>adenosine 5'-[beta,gamma-imido]triphosphate>or=adenosine 5'-[beta,gamma-methylene]triphosphate, whereas AMP, GTP and CTP were ineffective. VCP was observed to possess very low ATPase activity, with nucleotide specificity similar to that for BzATP binding. Conformational changes induced by an alternating site mechanism for ATP binding are suggested as a molecular mechanism for coupling ATP binding to the diverse activities of the AAA family. PMID:12747802

  7. Spontaneous rupture of ovarian cystadenocarcinoma: pre- and post-rupture computed tomography evaluation*

    PubMed Central

    Salvadori, Priscila Silveira; Bomfim, Lucas Novais; von Atzingen, Augusto Castelli; D’Ippolito, Giuseppe

    2015-01-01

    Epithelial ovarian tumors are the most common malignant ovarian neoplasms and, in most cases, eventual rupture of such tumors is associated with a surgical procedure. The authors report the case of a 54-year-old woman who presented with spontaneous rupture of ovarian cystadenocarcinoma documented by computed tomography, both before and after the event. In such cases, a post-rupture staging tends to be less favorable, compromising the prognosis. PMID:26543286

  8. Spontaneous rupture of ovarian cystadenocarcinoma: pre- and post-rupture computed tomography evaluation.

    PubMed

    Salvadori, Priscila Silveira; Bomfim, Lucas Novais; von Atzingen, Augusto Castelli; D'Ippolito, Giuseppe

    2015-01-01

    Epithelial ovarian tumors are the most common malignant ovarian neoplasms and, in most cases, eventual rupture of such tumors is associated with a surgical procedure. The authors report the case of a 54-year-old woman who presented with spontaneous rupture of ovarian cystadenocarcinoma documented by computed tomography, both before and after the event. In such cases, a post-rupture staging tends to be less favorable, compromising the prognosis. PMID:26543286

  9. Traumatic Gallbladder Rupture Treated by Laparoscopic Cholecystectomy

    PubMed Central

    Egawa, Noriyuki; Ueda, Junji; Hiraki, Masatsugu; Ide, Takao; Inoue, Satoshi; Sakamoto, Yuichiro; Noshiro, Hirokazu

    2016-01-01

    Abstract Gallbladder rupture due to blunt abdominal injury is rare. There are few reports of traumatic gallbladder injury, and it is commonly associated with other concomitant visceral injuries. Therefore, it is difficult to diagnose traumatic gallbladder rupture preoperatively when it is caused by blunt abdominal injury. We report a patient who underwent laparoscopic cholecystectomy after an exact preoperative diagnosis of traumatic gallbladder rupture. A 43-year-old man was admitted to our hospital due to blunt abdominal trauma. The day after admission, abdominal pain and ascites increased and a muscular defense sign appeared. Percutaneous drainage of the ascites was performed, and the aspirated fluid was bloody and almost pure bile. He was diagnosed with gallbladder rupture by the cholangiography using the endoscopic retrograde cholangiopancreatography technique. Laparoscopic cholecystectomy was performed safely, and he promptly recovered. If accumulated fluids contain bile, endoscopic cholangiography is useful not only to diagnose gallbladder injury but also to determine the therapeutic strategy. PMID:27462188

  10. Traumatic Gallbladder Rupture Treated by Laparoscopic Cholecystectomy.

    PubMed

    Egawa, Noriyuki; Ueda, Junji; Hiraki, Masatsugu; Ide, Takao; Inoue, Satoshi; Sakamoto, Yuichiro; Noshiro, Hirokazu

    2016-01-01

    Gallbladder rupture due to blunt abdominal injury is rare. There are few reports of traumatic gallbladder injury, and it is commonly associated with other concomitant visceral injuries. Therefore, it is difficult to diagnose traumatic gallbladder rupture preoperatively when it is caused by blunt abdominal injury. We report a patient who underwent laparoscopic cholecystectomy after an exact preoperative diagnosis of traumatic gallbladder rupture. A 43-year-old man was admitted to our hospital due to blunt abdominal trauma. The day after admission, abdominal pain and ascites increased and a muscular defense sign appeared. Percutaneous drainage of the ascites was performed, and the aspirated fluid was bloody and almost pure bile. He was diagnosed with gallbladder rupture by the cholangiography using the endoscopic retrograde cholangiopancreatography technique. Laparoscopic cholecystectomy was performed safely, and he promptly recovered. If accumulated fluids contain bile, endoscopic cholangiography is useful not only to diagnose gallbladder injury but also to determine the therapeutic strategy. PMID:27462188

  11. Architecture and Nucleotide-Dependent Conformational Changes of the Rvb1-Rvb2 AAA+ Complex Revealed by Cryoelectron Microscopy.

    PubMed

    Ewens, Caroline A; Su, Min; Zhao, Liang; Nano, Nardin; Houry, Walid A; Southworth, Daniel R

    2016-05-01

    Rvb1 and Rvb2 are essential AAA+ proteins that interact together during the assembly and activity of diverse macromolecules including chromatin remodelers INO80 and SWR-C, and ribonucleoprotein complexes including telomerase and snoRNPs. ATP hydrolysis by Rvb1/2 is required for function; however, the mechanism that drives substrate remodeling is unknown. Here we determined the architecture of the yeast Rvb1/2 dodecamer using cryoelectron microscopy and identify that the substrate-binding insertion domain undergoes conformational changes in response to nucleotide state. 2D and 3D classification defines the dodecamer flexibility, revealing distinct arrangements and the hexamer-hexamer interaction interface. Reconstructions of the apo, ATP, and ADP states identify that Rvb1/2 undergoes substantial conformational changes that include a twist in the insertion-domain position and a corresponding rotation of the AAA+ ring. These results reveal how the ATP hydrolysis cycle of the AAA+ domains directs insertion-domain movements that could provide mechanical force during remodeling or helicase activities. PMID:27112599

  12. Chaperone-like activity of the AAA+ proteins Rvb1 and Rvb2 in the assembly of various complexes

    PubMed Central

    Nano, Nardin; Houry, Walid A.

    2013-01-01

    Rvb1 and Rvb2 are highly conserved and essential eukaryotic AAA+ proteins linked to a wide range of cellular processes. AAA+ proteins are ATPases associated with diverse cellular activities and are characterized by the presence of one or more AAA+ domains. These domains have the canonical Walker A and Walker B nucleotide binding and hydrolysis motifs. Rvb1 and Rvb2 have been found to be part of critical cellular complexes: the histone acetyltransferase Tip60 complex, chromatin remodelling complexes Ino80 and SWR-C, and the telomerase complex. In addition, Rvb1 and Rvb2 are components of the R2TP complex that was identified by our group and was determined to be involved in the maturation of box C/D small nucleolar ribonucleoprotein (snoRNP) complexes. Furthermore, the Rvbs have been associated with mitotic spindle assembly, as well as phosphatidylinositol 3-kinase-related protein kinase (PIKK) signalling. This review sheds light on the potential role of the Rvbs as chaperones in the assembly and remodelling of these critical complexes. PMID:23530256

  13. [Centralisation of treatment of ruptured aneurysm].

    PubMed

    Akkersdijk, Willem L; Akkersdijk, George J M; Akkersdijk, George P

    2014-01-01

    In the future, patients with a ruptured aneurysm will be treated at fewer hospitals in the Netherlands. Although there is a search for scientific support for this, the reason for centralisation is obvious: reduction of costs and reduction of workload for vascular surgeons during night and weekend shifts. Already there are a number of examples of regionally organised vascular surgeons who treat their patients with a ruptured aneurysm with great satisfaction and with good results. PMID:25563776

  14. Dynamic rupture activation of backthrust fault branching

    NASA Astrophysics Data System (ADS)

    Xu, Shiqing; Fukuyama, Eiichi; Ben-Zion, Yehuda; Ampuero, Jean-Paul

    2015-03-01

    We perform dynamic rupture simulations to investigate the possible reactivation of backthrust branches triggered by ruptures along a main thrust fault. Simulations with slip-weakening fault friction and uniform initial stress show that fast propagation speed or long propagation distance of the main rupture promotes reactivation of backthrust over a range of branch angles. The latter condition may occur separately from the former if rupture speed is limited by an increasing slip-weakening distance towards the junction direction. The results suggest a trade-off between the amplitude and duration of the dynamic stress near the main rupture front for backthrust reactivation. Termination of the main rupture by a barrier can provide enhanced loading amplitude and duration along a backthrust rooted near the barrier, facilitating its reactivation especially with a high frictional resistance. The free surface and depth-dependent initial stress can have several additional effects. The sign of the triggered motion along the backthrust can be reversed from thrust to normal if a deeply nucleated main rupture breaks the free surface, while it is preserved as thrust if the main rupture is terminated by a barrier at depth. The numerical results are discussed in relation to several recent megathrust earthquakes in Sumatra, Chile, and Japan, and related topics such as branch feedbacks to the main fault. The dynamic view on backthrust fault branching provided by the study fills a gap not covered by quasi-static models or observations. A specific examined case of antithetic fault branching may be useful for indicating a barrier-like behavior along the main fault.

  15. Describing Soils: Calibration Tool for Teaching Soil Rupture Resistance

    ERIC Educational Resources Information Center

    Seybold, C. A.; Harms, D. S.; Grossman, R. B.

    2009-01-01

    Rupture resistance is a measure of the strength of a soil to withstand an applied stress or resist deformation. In soil survey, during routine soil descriptions, rupture resistance is described for each horizon or layer in the soil profile. The lower portion of the rupture resistance classes are assigned based on rupture between thumb and…

  16. Rupture Propagation for Stochastic Fault Models

    NASA Astrophysics Data System (ADS)

    Favreau, P.; Lavallee, D.; Archuleta, R.

    2003-12-01

    The inversion of strong motion data of large earhquakes give the spatial distribution of pre-stress on the ruptured faults and it can be partially reproduced by stochastic models, but a fundamental question remains: how rupture propagates, constrained by the presence of spatial heterogeneity? For this purpose we investigate how the underlying random variables, that control the pre-stress spatial variability, condition the propagation of the rupture. Two stochastic models of prestress distributions are considered, respectively based on Cauchy and Gaussian random variables. The parameters of the two stochastic models have values corresponding to the slip distribution of the 1979 Imperial Valley earthquake. We use a finite difference code to simulate the spontaneous propagation of shear rupture on a flat fault in a 3D continuum elastic body. The friction law is the slip dependent friction law. The simulations show that the propagation of the rupture front is more complex, incoherent or snake-like for a prestress distribution based on Cauchy random variables. This may be related to the presence of a higher number of asperities in this case. These simulations suggest that directivity is stronger in the Cauchy scenario, compared to the smoother rupture of the Gauss scenario.

  17. Intestinal rupture in a Mexican gray wolf (Canis lupus baileyi) in association with ingestion of a diazinon-impregnated cattle ear tag.

    PubMed

    Kagan, Rebecca

    2013-01-01

    A free-ranging Mexican gray wolf (Canis lupus baileyi) suffered intestinal rupture following ingestion of an insecticidal cattle ear tag. Subsequent organophosphate toxicosis as a cause of the rupture was speculated. Insecticidal ear tags could represent a poisoning risk in canids and other wildlife scavengers. PMID:23307392

  18. Association between statin therapy and tendon rupture: a case-control study.

    PubMed

    Beri, Abhimanyu; Dwamena, Francesca C; Dwamena, Ben A

    2009-05-01

    Although case reports of a possible association between statin therapy and tendon rupture have been published, no analytical studies exploring this relationship have been reported. We conducted a case-control study using the electronic medical records at Michigan State University from 2002 to 2007 to assess whether statin use is a risk factor for tendon rupture. We compared exposure to statins in 93 cases of tendon rupture with similar exposure in 279 sex- and age-matched controls. Exposure to statins was defined as documentation in the electronic medical record of statin use in the 12 months preceding tendon rupture. For controls, the exposure period was defined as 1 year preceding the last office visit. We used a multivariate logistic regression model, controlling for diabetes, renal disease, rheumatologic disease, and steroid use, to calculate the adjusted odds ratios (ORs). There was no significant difference between cases and controls in the rates of statin use, with either univariate [OR = 1.0, 95% confidence interval (CI) 0.54-1.84] or multivariate analyses (OR = 1.10, 95% CI 0.57-2.13). Based on predetermined subgroup analyses, statin exposure was found to be a significant risk factor for tendon rupture in women (adjusted OR = 3.76, 95% CI 1.11-12.75) but not in men (adjusted OR = 0.66, 95% CI 0.29-1.51). In conclusion, we found no overall association between statin use and tendon rupture, but subgroup analysis suggested that women with tendon rupture were more likely to be on statins. PMID:19454900

  19. Differential Sex Response to Aspirin in Decreasing Aneurysm Rupture in Humans and Mice.

    PubMed

    Chalouhi, Nohra; Starke, Robert M; Correa, Tatiana; Jabbour, Pascal M; Zanaty, Mario; Brown, Robert D; Torner, James C; Hasan, David M

    2016-08-01

    We previously found that aspirin decreases the risk of cerebral aneurysm rupture in humans. We aim to assess whether a sex differential exists in the response of human cerebral aneurysms to aspirin and confirm these observations in a mouse model of cerebral aneurysm. A nested case-control analysis from the International Study of Unruptured Intracranial Aneurysms was performed to assess whether a sex differential exists in the response of human cerebral aneurysms to aspirin. A series of experiments were subsequently performed in a mouse model of cerebral aneurysms. Aneurysms were induced with hypertension and elastase injection into mice basal cisterns. We found that aspirin decreased the risk of aneurysm rupture more significantly in men than in women in the International Study of Unruptured Intracranial Aneurysms. In mice, aspirin and cyclooxygenase-2 inhibitor did not affect cerebral aneurysm formation but significantly decreased the incidence of rupture. The incidence of rupture was significantly lower in male versus female mice on aspirin. Gene expression analysis from cerebral arteries showed higher 15-hydroxyprostaglandin dehydrogenase levels in male mice. The rate of cerebral aneurysm rupture was similar in male mice receiving aspirin and 15-hydroxyprostaglandin dehydrogenase inhibitor compared with females receiving aspirin and 15-hydroxyprostaglandin dehydrogenase agonist, signaling a reversal of the sex-differential response to aspirin. Aspirin decreases aneurysm rupture in human and mice, in part through cyclooxygenase-2 pathways. Evidence from animal and human studies suggests a consistent differential effect by sex. 15-Hydroxyprostaglandin dehydrogenase activation in females reduces the incidence of rupture and eliminates the sex-differential response to aspirin. PMID:27296993

  20. Spontaneous uterine rupture after abdominal myomectomy at the gestational age of 20 weeks in pregnancy: A case report

    PubMed Central

    Pakniat, Hamideh; Soofizadeh, Nasrin; Khezri, Marzieh Beigom

    2016-01-01

    Background: Uterine rupture in pregnancy is rare and often could be life threatening and catastrophic. Myomectomy is one of very common surgeries in gynecology, performed as the vaginal, abdominal and laparoscopic surgeries. Pregnancies occured after abdominal and laparoscopic myomectomy are high risk for uterine rapture. Case: Patient was a 28 Years old female, pregnant woman at the 20 wks of gestational age with abdominal pain and a history of abdominal myomectomy 6 yrs ago. Uterus was ruptured and fetus in amniotic sac was found in abdominal cavity. Conclusion: Early diagnosis of uterine rupture after myomectomy can save patients from death. PMID:27525334

  1. Is Statin Use Associated With Tendon Rupture? A Population-Based Retrospective Cohort Analysis.

    PubMed

    Contractor, Tahmeed; Beri, Abhimanyu; Gardiner, Joseph C; Tang, Xiaoqin; Dwamena, Francesca C

    2015-01-01

    Previous case reports and small studies have suggested that 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors (HMG-CoA-Is) may increase the risk of tendon rupture. We conducted a population-based retrospective cohort evaluation to better assess this relationship. From approximately 800,000 enrollees of a private insurance database, those who were aged ≤64 years with at least 1 year of continuous enrollment were selected. Exposure was defined as initiation of HMG-CoA-I after the beginning of the study period. Each exposed person was matched with 2 controls of similar age and gender. Baseline characteristics, including known risk factors for tendon rupture, were compared between exposed and control cohorts with fidelity to the study's matched design. After adjusting for differences in follow-up and baseline characteristics, incidence rate ratios for tendon rupture was assessed in HMG-CoA-I users and nonusers. A total of 34,749 exposed patients were matched with 69,498 controls. There was no difference in the occurrence of tendon ruptures in HMG-CoA-I users versus nonusers. The results remained unchanged after adjustment for age and gender. In conclusion, this population-based retrospective cohort evaluation suggests that use of HMG-CoA-Is as a group are not associated with tendon rupture. PMID:24451300

  2. Interleukin-6 as a Prognostic Biomarker in Ruptured Intracranial Aneurysms

    PubMed Central

    Kao, Hung-Wen; Kuo, Chen-Ling; Huang, Ching-Shan; Tseng, Wan-Min; Lin, Ching-Po

    2015-01-01

    Background Interleukin-6 (IL-6), a proinflammatory cytokine, was found to surge in the cerebral spinal fluid after aneurysmal subarachnoid hemorrhage (SAH). We hypothesized that the plasma level of IL-6 could be an independent biomarker in predicting clinical outcome of patients with ruptured intracranial aneurysm. Methods We prospectively included 53 consecutive patients treated with platinum coil embolization of the ruptured intracranial aneurysm. Plasma IL-6 levels were measured in the blood samples at the orifices of the aneurysms and from peripheral veins. The outcome measure was the modified Rankin Scale one month after SAH. Multiple logistic regression analyses were used to evaluate the associations between the plasma IL-6 levels and the neurological outcome. Results Significant risk factors for the poor outcome were old age, low Glasgow Coma Scale (GCS) on day 0, high Fisher grades, and high aneurysmal and venous IL-6 levels in univariate analyses. Aneurysmal IL-6 levels showed modest to moderate correlations with GCS on day 0, vasospasm grade and Fisher grade. A strong correlation was found between the aneurysmal and the corresponding venous IL-6 levels (ρ = 0.721; P<0.001). In the multiple logistic regression models, the poor 30-day mRS was significantly associated with high aneurysmal IL-6 level (OR, 17.97; 95% CI, 1.51–214.33; P = 0.022) and marginally associated with high venous IL-6 level (OR, 12.71; 95% CI, 0.90–180.35; P = 0.022) after adjusting for dichotomized age, GCS on day 0, and vasospasm and Fisher grades. Conclusions The plasma level of IL-6 is an independent prognostic biomarker that could be used to aid in the identification of patients at high-risk of poor neurological outcome after rupture of the intracranial aneurysm. PMID:26176774

  3. Rupture Following Biceps-to-Triceps Tendon Transfer in Adolescents and Young Adults With Spinal Cord Injury:

    PubMed Central

    Merenda, Lisa A.; Rutter, Laure; Curran, Kimberly; Kozin, Scott H.

    2012-01-01

    Background: Tendon transfer surgery can restore elbow extension in approximately 70% of persons with tetraplegia and often results in antigravity elbow extension strength. However, we have noted an almost 15% rupture/attenuation rate. Objective: This investigation was conducted to analyze potential causes in adolescents/young adults with spinal cord injury (SCI) who experienced tendon rupture or attenuation after biceps-to-triceps transfer. Methods: Medical charts of young adults with SCI who underwent biceps-to-triceps transfer and experienced tendon rupture or attenuation were reviewed. Data collected by retrospective chart review included general demographics, surgical procedure(s), use and duration of antibiotic treatment, time from tendon transfer surgery to rupture/attenuation, and method of diagnosis. Results: Twelve subjects with tetraplegia (mean age, 19 years) who underwent biceps-to-triceps reconstruction with subsequent tendon rupture or attenuation were evaluated. Mean age at time of tendon transfer was 18 years (range, 14-21 years). A fluoroquinolone was prescribed for 42% (n=5) of subjects. Tendon rupture was noted in 67% (n=8), and attenuation was noted in 33% (n=4). Average length of time from surgery to tendon rupture/attenuation was 5.7 months (range, 3-10 months). Conclusion: Potential contributing causes of tendon rupture/attenuation after transfer include surgical technique, rehabilitation, co-contraction of the transfer, poor patient compliance, and medications. In this cohort, 5 subjects were prescribed fluoroquinolones that have a US Food and Drug Administration black box concerning tendon ruptures. Currently, all candidates for upper extremity tendon transfer reconstruction are counseled on the effects of fluoroquinolones and the potential risk for tendon rupture. PMID:23459326

  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. Crystal structure of a novel archaeal AAA+ ATPase SSO1545 from Sulfolobus solfataricus

    SciTech Connect

    Xu, Qingping; Rife, Christopher L.; Carlton, Dennis; Miller, Mitchell D.; Krishna, S. Sri; Elsliger, Marc-André; Abdubek, Polat; Astakhova, Tamara; Chiu, Hsiu-Ju; Clayton, Thomas; Duan, Lian; Feuerhelm, Julie; Grzechnik, Slawomir K.; Hale, Joanna; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kumar, Abhinav; McMullan, Daniel; Morse, Andrew T.; Nigoghossian, Edward; Okach, Linda; Oommachen, Silvya; Paulsen, Jessica; Reyes, Ron; van den Bedem, Henry; Hodgson, Keith O.; Wooley, John; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.

    2009-08-28

    Signal transduction ATPases with numerous domains (STAND), a large class of P-loop NTPases, belong to AAA+ ATPases. They include AP(apoptotic)-ATPases (e.g., animal apoptosis regulators CED4/Apaf-1, plant disease resistance proteins, and bacterial AfsR-like transcription regulators), NACHT NTPases (e.g. CARD4, NAIP, Het-E-1, TLP1), and several other less well-characterized families. STAND differ from other P-loop NTPases by their unique sequence motifs, which include an hhGRExE (h, hydrophobic; x, any residue) motif at the N-terminal region, a GxP/GxxP motif at the C-terminal region of the NTPase domain, in addition to a C-terminal helical domain and additional domains such as WD40, TPR, LRR or catalytic modules. Despite significant biological interests, structural coverage of STAND proteins is very limited and only two other structures are currently known: the cell death regulators Apaf-1 and CED-4. Here, we report the crystal structure of SSO1545 from Sulfolobus solfataricus, which was determined using the semi-automated, high-throughput pipeline of the Joint Center for Structural Genomics (JCSG; http://www.jcsg.org), as part of the National Institute of General Medical Sciences' Protein Structure Initiative (PSI). SSO1545 (NP-342973.1), a representative of the archaeal STANDs, is a member of Pfam PF01637 and encodes a protein of 356 residues with calculated molecular weight and isoelectric point of 41.7 kD and 8.2, respectively.

  6. A proteomic study of Corynebacterium glutamicum AAA+ protease FtsH

    PubMed Central

    Lüdke, Alja; Krämer, Reinhard; Burkovski, Andreas; Schluesener, Daniela; Poetsch, Ansgar

    2007-01-01

    Background The influence of the membrane-bound AAA+ protease FtsH on membrane and cytoplasmic proteins of Corynebacterium glutamicum was investigated in this study. For the analysis of the membrane fraction, anion exchange chromatography was combined with SDS-PAGE, while the cytoplasmic protein fraction was studied by conventional two-dimensional gel electrophoresis. Results In contrast to the situation in other bacteria, deletion of C. glutamicum ftsH has no significant effect on growth in standard minimal medium or response to heat or osmotic stress. On the proteome level, deletion of the ftsH gene resulted in a strong increase of ten cytoplasmic and membrane proteins, namely biotin carboxylase/biotin carboxyl carrier protein (accBC), glyceraldehyde-3-phosphate dehydrogenase (gap), homocysteine methyltransferase (metE), malate synthase (aceB), isocitrate lyase (aceA), a conserved hypothetical protein (NCgl1985), succinate dehydrogenase A (sdhA), succinate dehydrogenase B (sdhB), succinate dehydrogenase CD (sdhCD), and glutamate binding protein (gluB), while 38 cytoplasmic and membrane-associated proteins showed a decreased abundance. The decreasing amount of succinate dehydrogenase A (sdhA) in the cytoplasmic fraction of the ftsH mutant compared to the wild type and its increasing abundance in the membrane fraction indicates that FtsH might be involved in the cleavage of a membrane anchor of this membrane-associated protein and by this changes its localization. Conclusion The data obtained hint to an involvement of C. glutamicum FtsH protease mainly in regulation of energy and carbon metabolism, while the protease is not involved in stress response, as found in other bacteria. PMID:17254330

  7. Single-molecule denaturation and degradation of proteins by the AAA+ ClpXP protease

    PubMed Central

    Shin, Yongdae; Davis, Joseph H.; Brau, Ricardo R.; Martin, Andreas; Kenniston, Jon A.; Baker, Tania A.; Sauer, Robert T.; Lang, Matthew J.

    2009-01-01

    ClpXP is an ATP-fueled molecular machine that unfolds and degrades target proteins. ClpX, an AAA+ enzyme, recognizes specific proteins, and then uses cycles of ATP hydrolysis to denature any native structure and to translocate the unfolded polypeptide into ClpP for degradation. Here, we develop and apply single-molecule fluorescence assays to probe the kinetics of protein denaturation and degradation by ClpXP. These assays employ a single-chain variant of the ClpX hexamer, linked via a single biotin to a streptavidin-coated surface, and fusion substrates with an N-terminal fluorophore and a C-terminal GFP-titin-ssrA module. In the presence of adenosine 5′-[γ-thio]triphosphate (ATPγS), ClpXP degrades the titin-ssrA portion of these substrates but stalls when it encounters GFP. Exchange into ATP then allows synchronous resumption of denaturation and degradation of GFP and any downstream domains. GFP unfolding can be monitored directly, because intrinsic fluorescence is quenched by denaturation. The time required for complete degradation coincides with loss of the substrate fluorophore from the protease complex. Fitting single-molecule data for a set of related substrates provides time constants for ClpX unfolding, translocation, and a terminal step that may involve product release. Comparison of these single-molecule results with kinetics measured in bulk solution indicates similar levels of microscopic and macroscopic ClpXP activity. These results support a stochastic engagement/unfolding mechanism that ultimately results in highly processive degradation and set the stage for more detailed single-molecule studies of machine function. PMID:19892734

  8. Maintenance of Nucleosomal Balance in cis by Conserved AAA-ATPase Yta7

    PubMed Central

    Lombardi, Laura M.; Davis, Matthew D.; Rine, Jasper

    2015-01-01

    The extent of chromatin compaction is a fundamental driver of nuclear metabolism . Yta7 is a chromatin-associated AAA-ATPase, the human ortholog of which, ANCCA/ATAD2 transcriptionally activates pathways of malignancy in a broad range of cancers. Yta7 directly binds histone H3, and bulk chromatin exhibits increased nucleosomal density in yta7Δ mutants. The suppression of yta7Δ mutant growth and transcriptional phenotypes in budding yeast by decreased dosage of histones H3 and H4 indicates the acute sensitivity of cells to deviations in nucleosome spacing. This study investigated the global changes in chromatin structure upon Yta7 loss or overexpression and determined which of these effects reflected direct Yta7 activity. Metagene analysis of Yta7’s genome-wide localization indicated peak binding of Yta7 just downstream of the transcription start site. Cells lacking Yta7 exhibited increased nucleosome density within genes downstream of the +1 nucleosome, as defined by decreased internucleosomal distance, resulting in progressively 5′-shifted nucleosomes within the gene. In contrast, cells overexpressing Yta7 displayed profound 3′-shifts in nucleosome position and reduced nucleosome density within genes. Importantly, Yta7-bound regions were enriched for nucleosomal shifts, indicating that Yta7 acted locally to modulate nucleosome spacing. The phenotype of cells lacking both Yta7 and Rtt106, the histone H3/H4 chaperone, indicated that Yta7 functions in both Rtt106-dependent and Rtt106-independent ways to modulate nucleosome spacing within genes. This study suggested that Yta7 affected nucleosome density throughout the gene by both blocking Rtt106 from entering the gene, as shown previously at HTA1, and facilitating the loss of nucleosomes from the 5′-end. PMID:25406467

  9. Management of abdomen hydatidosis after rupture of a hydatid splenic cyst: a case report

    PubMed Central

    Soultanidis, Chrisostomos; Kirmanidis, Michail A; Tsigalou, Christina; Deftereos, Savvas

    2009-01-01

    We present a case of multiple hydatidosis in an 8-year-old boy that resulted from a ruptured hydatid cyst of the spleen and spread into the peritoneal cavity. We also present a new approach for managing these difficult and high-risk cases. PMID:19918429

  10. Spontaneous rupture of unscarred uterus in a primigravida with preterm prelabour rupture of membranes.

    PubMed

    Mourad, Wael Sayed; Bersano, Debbra J; Greenspan, Peter B; Harper, Diane Medved

    2015-01-01

    Intrapartum uterine rupture is a true obstetrical emergency. Uterine rupture is associated with severe maternal and fetal morbidity and mortality. It is rare in the unscarred uterus of a primigravida. A 23-year-old primigravida with an unscarred uterus was admitted with preterm prelabour rupture of membranes at 36(+4) weeks of gestation. Abnormal fetal heart monitoring, associated with acute onset of severe abdominopelvic pain, developed on admission. Rupture occurred prior to onset of regular uterine contractions and in the absence of any interventional oxytocin. The neonate had evidence of severe acidosis despite emergency caesarean delivery. This case highlights the importance of maintaining a high index of suspicion for uterine rupture, even in the unlikely setting of a primigravida with an unscarred uterus. PMID:26055584

  11. A Rare Case of Simultaneous Acute Bilateral Quadriceps Tendon Rupture and Unilateral Achilles Tendon Rupture

    PubMed Central

    Leong, Wei Yee; Gheorghiu, Daniel; Rao, Janardhan

    2013-01-01

    Introduction: There have been multiple reported cases of bilateral quadriceps tendon ruptures (QTR) in the literature. These injuries frequently associated with delayed diagnosis, which results in delayed surgical treatment. In very unusual cases, bilateral QTRs can be associated with other simultaneous tendon ruptures. Case Report: We present a rare case of bilateral QTR with a simultaneous Achilles Tendon Rupture involving a 31 years old Caucasian man who is a semi-professional body builder taking anabolic steroids. To date bilateral QTR with additional TA rupture has only been reported once in the literature and to our knowledge this is the first reported case of bilateral QTR and simultaneous TA rupture in a young, fit and healthy individual. Conclusion: The diagnosis of bilateral QTR alone can sometimes be challenging and the possibility of even further tendon injuries should be carefully assessed. A delay in diagnosis could result in delay in treatment and potentially worse outcome for the patient. PMID:27298913

  12. Rituximab-Induced Splenic Rupture and Cytokine Release

    PubMed Central

    Nair, Ranjit; Gheith, Shereen; Lamparella, Nicholas

    2016-01-01

    Patient: Female, 55 Final Diagnosis: Mantle cell lymphoma Symptoms: Cytokine release syndrome • hypoglycemia • hypotension • splenic rupture • splenomegaly • vision loss Medication: — Clinical Procedure: Case Report Specialty: Oncology Objective: Unusual clinical course Background: Rituximab is a therapeutic monoclonal antibody that is used for many different lymphomas. Post-marketing surveillance has revealed that the risk of fatal reaction with rituximab use is extremely low. Splenic rupture and cytokine release syndrome are rare fatal adverse events related to the use of therapeutic monoclonal antibodies, especially in aggressive malignancies with high tumor burden. Case Report: A 55-year-old woman presented with abdominal pain and type B symptoms and was diagnosed with mantle cell lymphoma. Initial peripheral blood flow cytometry showed findings that mimicked features of chronic lymphocytic leukemia. Further treatment with rituximab led to catastrophic treatment complications that proved to be fatal for the patient. Conclusions: Severe cytokine release syndrome associated with biologics carries a very high morbidity and case fatality rate. With this case report we aim to present the diagnostic challenge with small B-cell neoplasms, especially mantle cell lymphoma and chronic lymphocytic lymphomas, and underscore the importance of thorough risk assessment for reactions prior to treatment initiation. PMID:26972227

  13. Dynamic rupture processes inferred from laboratory microearthquakes

    NASA Astrophysics Data System (ADS)

    Passelègue, François. X.; Schubnel, Alexandre; Nielsen, Stefan; Bhat, Harsha S.; Deldicque, Damien; Madariaga, Raúl

    2016-06-01

    We report macroscopic stick-slip events in saw-cut Westerly granite samples deformed under controlled upper crustal stress conditions in the laboratory. Experiments were conducted under triaxial loading (σ1>σ2=σ3) at confining pressures (σ3) ranging from 10 to 100 MPa. A high-frequency acoustic monitoring array recorded particle acceleration during macroscopic stick-slip events allowing us to estimate rupture speed. In addition, we record the stress drop dynamically and we show that the dynamic stress drop measured locally close to the fault plane is almost total in the breakdown zone (for normal stress >75 MPa), while the friction f recovers to values of f > 0.4 within only a few hundred microseconds. Enhanced dynamic weakening is observed to be linked to the melting of asperities which can be well explained by flash heating theory in agreement with our postmortem microstructural analysis. Relationships between initial state of stress, rupture velocities, stress drop, and energy budget suggest that at high normal stress (leading to supershear rupture velocities), the rupture processes are more dissipative. Our observations question the current dichotomy between the fracture energy and the frictional energy in terms of rupture processes. A power law scaling of the fracture energy with final slip is observed over 8 orders of magnitude in slip, from a few microns to tens of meters.

  14. Bilateral supraclavicular swelling: an unusual presentation of ruptured Poly Implant Prosthese (PIP) breast implants.

    PubMed

    Manickavasagar, Tharjan; Morritt, Andrew N; Offer, Graham J

    2013-02-01

    Breast implants manufactured by the French company Poly Implant Prosthese (PIP) have gained notoriety in the International media since the realisation that industrial grade silicone was used in their manufacture with consequent increased risk of implant rupture. At present, it is estimated that there are estimated to be over 40,000 women in the UK with PIP implants. We report an unusual presentation of PIP breast implant rupture as swelling in the supraclavicular fossae. This has not previously been reported in the literature. PMID:22836112

  15. Right ventricular hydatid cyst ruptured to pericardium

    PubMed Central

    Sabzi, Feridoun; Vaziri, Siavoosh; Faraji, Reza

    2015-01-01

    Cardiac hydatidosis is rare presentation of body hydatidosis. Incidence of cardiac involvements range from 5% to 5% of patients with hydatid disease. Most common site of hydatid cyst in heart is interventricular septum and left ventricular free wall. Right ventricular free wall involvement by cyst that ruptured to pericardial cavity is very rare presentation of hydatid cyst. Cardiac involvement may have serious consequences such as rupture to blood steam or pericardial cavity. Both the disease and its surgical treatment carry a high complication rate, including rupture leading to cardiac tamponade, anaphylaxis and also death. In the present report, a 43-year-old man with constrictive pericarditis secondary to a pericardial hydatid cyst is described. PMID:26139761

  16. Anterior cruciate ligament rupture and osteoarthritis progression.

    PubMed

    Wong, James Min-Leong; Khan, Tanvir; Jayadev, Chethan S; Khan, Wasim; Johnstone, David

    2012-01-01

    Anterior Cruciate Ligament (ACL) rupture is a common sporting injury that frequently affects young, athletic patients. Apart from the functional problems of instability, patients with ACL deficient knees also develop osteoarthritis. Although this is frequently cited as an indication for ACL reconstruction, the relationship between ACL rupture, reconstruction and the instigation and progression of articular cartilage degenerative change is controversial.The purpose of this paper is to review the published literature with regards ACL rupture and the multifactorial causes for osteoarthritis progression, and whether or not this is slowed or stopped by ACL reconstruction.There is no evidence in the published literature to support the view that ACL reconstruction prevents osteoarthritis, although it may prevent further meniscal damage. It must be recognised that this conclusion is based on the current literature which has substantial methodological limitations. PMID:22896777

  17. Creep rupture behavior of unidirectional advanced composites

    NASA Technical Reports Server (NTRS)

    Yeow, Y. T.

    1980-01-01

    A 'material modeling' methodology for predicting the creep rupture behavior of unidirectional advanced composites is proposed. In this approach the parameters (obtained from short-term tests) required to make the predictions are the three principal creep compliance master curves and their corresponding quasi-static strengths tested at room temperature (22 C). Using these parameters in conjunction with a failure criterion, creep rupture envelopes can be generated for any combination of in-plane loading conditions and ambient temperature. The analysis was validated experimentally for one composite system, the T300/934 graphite-epoxy system. This was done by performing short-term creep tests (to generate the principal creep compliance master curves with the time-temperature superposition principle) and relatively long-term creep rupture tensile tests of off-axis specimens at 180 C. Good to reasonable agreement between experimental and analytical results is observed.

  18. Ruptured, Intracranial Dermoid Cyst - A Visual Diagnosis?

    PubMed Central

    Scheer, Fabian; Andresen, Reimer

    2016-01-01

    Dermoid cysts are a very rare entity of intracranial tumours. The traumatic or non-traumatic rupture of the cyst wall is a serious complication that can be treated surgically or conservatively depending on the clinical symptoms. However, more common entities have to be considered as a differential diagnosis. We report on a female patient who was admitted with complaints of significant, prolonged headache and diffuse pain. Analysis of her blood and cerebrospinal fluid indicated no clear pathology. A CT examination of the head revealed a ruptured dermoid cyst adjacent to the left sphenoidal bone. An additional MRI was conducted to confirm the CT findings and rule out an intracranial ischemia or vasospasms. A conservative therapy was scheduled and the patient recovered well. Using current imaging techniques, especially magnetic resonance imaging, it is possible to identify a ruptured dermoid cyst by its pathognomonic signal behavior and rule out potentially life threatening complications. PMID:27190918

  19. A Late Presentation of Spontaneous Bladder Rupture During Labor.

    PubMed

    Farahzadi, A; Mohammadipour, S

    2016-09-01

    Spontaneous bladder rupture is usually due to bladder diseases. Bladder rupture during labor or postpartum is extremely rare. Acute abdomen is the usual presentation of spontaneous bladder rupture. Patients may complain of suprapubic pain, anuria and hematuria. Some patients with intraperitoneal bladder rupture may have no abdominal pain and can pass urine without any symptoms so the diagnosis of intraperitoneal rupture may be difficult in these situations. We report a nulliparous woman with abdominal pain and distension about 20 days after normal vaginal delivery. There was intraperitoneal rupture of bladder in dome of bladder which was sealed by jejunum. PMID:27313990

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

    PubMed

    Bozeman, Matthew C; Ross, Charles B

    2012-01-01

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

  1. Spontaneous, bilateral, quadriceps tendon rupture caused by local exposure to methidathion.

    PubMed

    Papastergiou, Stergios G; Koukoulias, Nikolaos E; Ziogas, Evangelos; Dimitriadis, Theofilos; Koumis, Panagiotis

    2009-01-01

    Spontaneous, bilateral, quadriceps tendon rupture is a rare injury. Many predisposing conditions have been reported that contribute to quadriceps tendon degeneration. We report a case of a 42-year-old farmer with spontaneous, bilateral, quadriceps tendon rupture and clear medical history. Clinical and laboratory investigations revealed no risk factors for tendon degeneration but the patient reported that he was exposed locally to methidathion 1 week before the rupture. Methidathion is an organophosphate insecticide commonly used in agriculture that is highly toxic via the dermal route. Methidathion induces lipid pre-oxidation and consequently alters quadriceps tendon blood supply and ultrastructure. The injury was treated with early surgical repair and final outcome was excellent 44 months postoperatively. PMID:22114623

  2. Spontaneous, bilateral, quadriceps tendon rupture caused by local exposure to methidathion

    PubMed Central

    Papastergiou, Stergios G; Koukoulias, Nikolaos E; Ziogas, Evangelos; Dimitriadis, Theofilos; Koumis, Panagiotis

    2009-01-01

    Spontaneous, bilateral, quadriceps tendon rupture is a rare injury. Many predisposing conditions have been reported that contribute to quadriceps tendon degeneration. We report a case of a 42-year-old farmer with spontaneous, bilateral, quadriceps tendon rupture and clear medical history. Clinical and laboratory investigations revealed no risk factors for tendon degeneration but the patient reported that he was exposed locally to methidathion 1 week before the rupture. Methidathion is an organophosphate insecticide commonly used in agriculture that is highly toxic via the dermal route. Methidathion induces lipid pre-oxidation and consequently alters quadriceps tendon blood supply and ultrastructure. The injury was treated with early surgical repair and final outcome was excellent 44 months postoperatively. PMID:22114623

  3. Rupture propagation behavior and the largest possible earthquake induced by fluid injection into deep reservoirs

    NASA Astrophysics Data System (ADS)

    Gischig, Valentin S.

    2015-09-01

    Earthquakes caused by fluid injection into deep underground reservoirs constitute an increasingly recognized risk to populations and infrastructure. Quantitative assessment of induced seismic hazard, however, requires estimating the maximum possible magnitude earthquake that may be induced during fluid injection. Here I seek constraints on an upper limit for the largest possible earthquake using source-physics simulations that consider rate-and-state friction and hydromechanical interaction along a straight homogeneous fault. Depending on the orientation of the pressurized fault in the ambient stress field, different rupture behaviors can occur: (1) uncontrolled rupture-front propagation beyond the pressure front or (2) rupture-front propagation arresting at the pressure front. In the first case, fault properties determine the earthquake magnitude, and the upper magnitude limit may be similar to natural earthquakes. In the second case, the maximum magnitude can be controlled by carefully designing and monitoring injection and thus restricting the pressurized fault area.

  4. COMPARISON OF CLADDING CREEP RUPTURE MODELS

    SciTech Connect

    P. Macheret

    2000-06-12

    The objective of this calculation is to compare several creep rupture correlations for use in calculating creep strain accrued by the Zircaloy cladding of spent nuclear fuel when it has been emplaced in the repository. These correlations are used to calculate creep strain values that are then compared to a large set of experimentally measured creep strain data, taken from four different research articles, making it possible to determine the best fitting correlation. The scope of the calculation extends to six different creep rupture correlations.

  5. Pectoralis major tendon rupture. Surgical procedures review.

    PubMed Central

    Merolla, Giovanni; Paladini, Paolo; Campi, Fabrizio; Porcellini, Giuseppe

    2012-01-01

    Summary Pectoralis major (PM) muscle is the powerful dynamic stabiliser of the shoulder that acts as a flexor, adductor and internal rotator. The rupture of the PM tendon is a relatively rare injury that was firstly described in a French boy by Patissier in 1822 and later, in 1861, by Letenneur who reported another similiar case. To date, over 200 cases have been published. In this article we describe the clinical anatomy and the mechanism of injuries of PM and we review the surgical procedures for acute and chronic ruptures. PMID:23738281

  6. [Traumatic diaphragmatic rupture with delayed unusual disclosure].

    PubMed

    Thicoïpé, M; Sztark, F; Lassié, P; Tueux, O; Dabadie, P

    1995-01-01

    The authors report the case of a delayed presentation of a traumatic diaphragmatic rupture in a 22-year-old patient admitted to hospital for a minor surgical procedure under general anaesthesia. Nine months before, he had a road traffic accident with a minor thoracic trauma. Three days after surgery, the patient was readmitted for a tension hydrothorax due to the herniation and the perforation of the stomach into the left pleural cavity. Such a delayed presentation of a traumatic diaphragmatic rupture remains uncommon. The peroperative ventilatory factors involved in the development of the hernia are discussed. PMID:8572411

  7. Thoracic Outlet Syndrome Following Breast Implant Rupture

    PubMed Central

    Caplash, Yugesh; Giri, Pratyush; Kearney, Daniel; Wagstaff, Marcus

    2015-01-01

    Summary: We present a patient with bilateral breast implant rupture who developed severe locoregional silicone granulomatous lymphadenopathy. Poly Implant Prothese silicone implants had been used for bilateral breast augmentation 5 years prior. Extracapsular implant rupture and bilateral axillary lymphadenopathy indicated explantation, capsulectomy, and selective lymph node excision. Histology demonstrated silicone lymphadenopathy with no evidence of malignancy. Over the subsequent 12 months, she developed progressive locoregional lymphadenopathy involving bilateral cervical, axillary, and internal mammary groups, resulting in bilateral thoracic outlet syndrome. We report the unusual presentation, progression, and the ultimate surgical management of this patient. PMID:25878942

  8. Ruptured rudimentary horn at 22 weeks.

    PubMed

    Dhar, Hansa

    2012-07-01

    Rudimentary horn is a developmental anomaly of the uterus. Pregnancy in a non-communicating rudimentary horn is very difficult to diagnose before it ruptures. A case of undiagnosed rudimentary horn pregnancy at 22 weeks presented to Nizwa regional referral hospital in shock with features of acute abdomen. Chances of rupture in first or second trimester are increased with catastrophic haemorrhage leading to increased maternal and perinatal morbidity and mortality. Management of such cases is a challenge till today due to diagnostic dilemma. Expertise in ultrasonography and early resort to surgical management is life saving in such cases. PMID:23293421

  9. Experimental Investigation of Thrust Fault Rupture Mechanics

    NASA Astrophysics Data System (ADS)

    Gabuchian, Vahe

    Thrust fault earthquakes are investigated in the laboratory by generating dynamic shear ruptures along pre-existing frictional faults in rectangular plates. A considerable body of evidence suggests that dip-slip earthquakes exhibit enhanced ground motions in the acute hanging wall wedge as an outcome of broken symmetry between hanging and foot wall plates with respect to the earth surface. To understand the physical behavior of thrust fault earthquakes, particularly ground motions near the earth surface, ruptures are nucleated in analog laboratory experiments and guided up-dip towards the simulated earth surface. The transient slip event and emitted radiation mimic a natural thrust earthquake. High-speed photography and laser velocimeters capture the rupture evolution, outputting a full-field view of photo-elastic fringe contours proportional to maximum shearing stresses as well as continuous ground motion velocity records at discrete points on the specimen. Earth surface-normal measurements validate selective enhancement of hanging wall ground motions for both sub-Rayleigh and super-shear rupture speeds. The earth surface breaks upon rupture tip arrival to the fault trace, generating prominent Rayleigh surface waves. A rupture wave is sensed in the hanging wall but is, however, absent from the foot wall plate: a direct consequence of proximity from fault to seismometer. Signatures in earth surface-normal records attenuate with distance from the fault trace. Super-shear earthquakes feature greater amplitudes of ground shaking profiles, as expected from the increased tectonic pressures required to induce super-shear transition. Paired stations measure fault parallel and fault normal ground motions at various depths, which yield slip and opening rates through direct subtraction of like components. Peak fault slip and opening rates associated with the rupture tip increase with proximity to the fault trace, a result of selective ground motion amplification in the

  10. [Gastric rupture after ingestion of liquid nitrogen].

    PubMed

    Knudsen, Anders Riegels; Nielsen, Casper; Christensen, Peter

    2009-02-01

    A 28-year-old male was admitted to hospital with severe abdominal distension and subcutaneous emphysema after ingesting 15 ml liquid nitrogen to produce an impressive burp. A rupture of the stomach at the lesser curvature was sutured by laparotomy. Peroperative gastroscopy showed no signs of cold-induced lesions. Liquid nitrogen boils at -196 degrees C. When heated to body temperature, it instantly expands 700 times, in this case predictably leading to gastric rupture. Therefore, any oral intake of even small amounts of liquid nitrogen should be avoided. PMID:19210943

  11. Spontaneous Achilles tendon rupture in alkaptonuria

    PubMed Central

    Alajoulin, Omar A.; Alsbou, Mohammed S.; Ja’afreh, Somayya O.; Kalbouneh, Heba M.

    2015-01-01

    Alkaptonuria (AKU) is a rare inborn metabolic disease characterized by accumulation of homogentisic acid (HGA). Excretion of HGA in urine causes darkening of urine and its deposition in connective tissues causes dark pigmentation (ochronosis), early degeneration of articular cartilage, weakening of the tendons, and subsequent rupture. In this case report, we present a rare case of a patient presented with unilateral spontaneous rupture of Achilles tendon due to AKU. The patient developed most of the orthopedic manifestations of the disease earlier than typical presentations. Alkaptonuria patients should avoid strenuous exercises and foot straining especially in patients developing early orthopedic manifestations. PMID:26620992

  12. A dosimetric evaluation of the Eclipse AAA algorithm and Millennium 120 MLC for cranial intensity-modulated radiosurgery

    SciTech Connect

    Calvo Ortega, Juan Francisco Moragues, Sandra; Pozo, Miquel; José, Sol San; Puertas, Enrique; Fernández, Jaime; Casals, Joan

    2014-07-01

    The aim of this study is to assess the accuracy of a convolution-based algorithm (anisotropic analytical algorithm [AAA]) implemented in the Eclipse planning system for intensity-modulated radiosurgery (IMRS) planning of small cranial targets by using a 5-mm leaf-width multileaf collimator (MLC). Overall, 24 patient-based IMRS plans for cranial lesions of variable size (0.3 to 15.1 cc) were planned (Eclipse, AAA, version 10.0.28) using fixed field-based IMRS produced by a Varian linear accelerator equipped with a 120 MLC (5-mm width on central leaves). Plan accuracy was evaluated according to phantom-based measurements performed with radiochromic film (EBT2, ISP, Wayne, NJ). Film 2D dose distributions were performed with the FilmQA Pro software (version 2011, Ashland, OH) by using the triple-channel dosimetry method. Comparison between computed and measured 2D dose distributions was performed using the gamma method (3%/1 mm). Performance of the MLC was checked by inspection of the DynaLog files created by the linear accelerator during the delivery of each dynamic field. The absolute difference between the calculated and measured isocenter doses for all the IMRS plans was 2.5% ± 2.1%. The gamma evaluation method resulted in high average passing rates of 98.9% ± 1.4% (red channel) and 98.9% ± 1.5% (blue and green channels). DynaLog file analysis revealed a maximum root mean square error of 0.46 mm. According to our results, we conclude that the Eclipse/AAA algorithm provides accurate cranial IMRS dose distributions that may be accurately delivered by a Varian linac equipped with a Millennium 120 MLC.

  13. Nanomechanical and Thermophoretic Analyses of the Nucleotide-Dependent Interactions between the AAA(+) Subunits of Magnesium Chelatase.

    PubMed

    Adams, Nathan B P; Vasilev, Cvetelin; Brindley, Amanda A; Hunter, C Neil

    2016-05-25

    In chlorophyll biosynthesis, the magnesium chelatase enzyme complex catalyzes the insertion of a Mg(2+) ion into protoporphyrin IX. Prior to this event, two of the three subunits, the AAA(+) proteins ChlI and ChlD, form a ChlID-MgATP complex. We used microscale thermophoresis to directly determine dissociation constants for the I-D subunits from Synechocystis, and to show that the formation of a ChlID-MgADP complex, mediated by the arginine finger and the sensor II domain on ChlD, is necessary for the assembly of the catalytically active ChlHID-MgATP complex. The N-terminal AAA(+) domain of ChlD is essential for complex formation, but some stability is preserved in the absence of the C-terminal integrin domain of ChlD, particularly if the intervening polyproline linker region is retained. Single molecule force spectroscopy (SMFS) was used to determine the factors that stabilize formation of the ChlID-MgADP complex at the single molecule level; ChlD was attached to an atomic force microscope (AFM) probe in two different orientations, and the ChlI subunits were tethered to a silica surface; the probability of subunits interacting more than doubled in the presence of MgADP, and we show that the N-terminal AAA(+) domain of ChlD mediates this process, in agreement with the microscale thermophoresis data. Analysis of the unbinding data revealed a most probable interaction force of around 109 pN for formation of single ChlID-MgADP complexes. These experiments provide a quantitative basis for understanding the assembly and function of the Mg chelatase complex. PMID:27133226

  14. Nanomechanical and Thermophoretic Analyses of the Nucleotide-Dependent Interactions between the AAA+ Subunits of Magnesium Chelatase

    PubMed Central

    2016-01-01

    In chlorophyll biosynthesis, the magnesium chelatase enzyme complex catalyzes the insertion of a Mg2+ ion into protoporphyrin IX. Prior to this event, two of the three subunits, the AAA+ proteins ChlI and ChlD, form a ChlID–MgATP complex. We used microscale thermophoresis to directly determine dissociation constants for the I-D subunits from Synechocystis, and to show that the formation of a ChlID–MgADP complex, mediated by the arginine finger and the sensor II domain on ChlD, is necessary for the assembly of the catalytically active ChlHID–MgATP complex. The N-terminal AAA+ domain of ChlD is essential for complex formation, but some stability is preserved in the absence of the C-terminal integrin domain of ChlD, particularly if the intervening polyproline linker region is retained. Single molecule force spectroscopy (SMFS) was used to determine the factors that stabilize formation of the ChlID–MgADP complex at the single molecule level; ChlD was attached to an atomic force microscope (AFM) probe in two different orientations, and the ChlI subunits were tethered to a silica surface; the probability of subunits interacting more than doubled in the presence of MgADP, and we show that the N-terminal AAA+ domain of ChlD mediates this process, in agreement with the microscale thermophoresis data. Analysis of the unbinding data revealed a most probable interaction force of around 109 pN for formation of single ChlID–MgADP complexes. These experiments provide a quantitative basis for understanding the assembly and function of the Mg chelatase complex. PMID:27133226

  15. Multicenter Orthopaedic Outcome Network Early Anti-inflammatory Treatment in Patients with Acute ACL Tear” (MOON-AAA) Clinical Trial

    PubMed Central

    Lattermann, Christian; Proffitt, Mary; Huston, Laura J.; Gammon, Lee; Johnson, Darren L.; Kraus, Virginia B.; Spindler, Kurt P.

    2016-01-01

    Objectives: We present the early results from the “Multicenter Orthopaedic Outcome Network Early Anti-inflammatory Treatment in Patients with Acute ACL Tear and Painful Effusions” (MOON-AAA) clinical trial (figure 1). This trial allows for a well controlled prospective cohort of patients with isolated ACL injury at risk for OA. We compared the effect of a single versus a repeated dosage of Kenalog within the first two weeks after ACL injury and its effect on chondral degradation in the first 4 weeks prior to surgical reconstruction of the ACL. Methods: 49 patients with isolated ACL tears were enrolled. Knee joints were aspirated and patients received an injection with 40 mg Kenalog either within 4 days, 10 days, both time points or not at all (saline injection control). Serum, synovial fluid and urine were collected at 3 time points. Permutated block randomization, triple blinding, independent monitoring and standardized x-ray was performed to comply with GCP standards. Patient reported outcomes were collected at 6 time points up to 6 months post-ACL reconstruction(IKDC, KOOS and Marx activity level). A standardized synovial fluid biomarker panel was analyzed according to OARSI guidelines. Statistical analysis were performed using SAS mixed models analysis. Results: Serum analysis shows significant change after injury. Chondrodegradatory markers such as CTX-II, MMP-1 and MMP-3 as well as COMP indicate a progressive destruction of chondral matrix and collagen breakdown . There is a dramatic (250%) increase of CTX-II in the first 4 weeks. Matrix proteins such as MMP-1 and 3 as well as COMP show an initial increase and then a steep decline (see figure 1). Inflammatory markers (IL-1 alpha, IL-1beta, IRAP) show a decline from the time of injury. IL-1 alpha, however shows a dramatic uptake after week 2. This longitudinal data confirms a dramatic onset of early osteoarthritic biomarker profiles immediately after ACL injury as measured in synovial fluid

  16. Triceps tendon rupture: the knowledge acquired from the anatomy to the surgical repair.

    PubMed

    Celli, A

    2015-09-01

    Triceps injuries are relatively uncommon in most traumatic events, and the distal triceps tendon ruptures are rare. Recently, the knowledge of this tendon lesion has increased, and it seems to be related to more precise diagnostic and clinical assessments. The most common mechanism of injury remains a forceful eccentric contraction of the muscle, while several other risk factors have been studied as chronic renal failure, endocrine disorders, metabolic bone diseases as well as steroid use. Olecranon bursitis and local corticosteroid injections may also play a role. The commonest site of rupture is at the tendon's insertion into the olecranon and rarely at the myotendinous junction or intramuscularly. The surgical intervention is recommended in acute complete ruptures, and non-operative treatment is reserved for patients with major comorbidities, as well as for partial ruptures with little functional disability and in low demanding patients. Various techniques and approaches as the direct repair to bone, the tendon augmentation, the anconeus rotation flap and the Achilles tendon allograft have been proposed for the management of these challenging injuries. The goal of surgical management should be an anatomical repair of the injured tendon by selection of a procedure with a low complication rate and one that allows early mobilization. This manuscript focuses the triceps tendon ruptures starting from the anatomy to the diagnosis and entity of the triceps tendon injuries, as well as the indications and guidelines for the management. PMID:25957546

  17. Derivative spectrophotometric analysis of cerebrospinal fluid for the detection of a ruptured cerebral aneurysm

    NASA Astrophysics Data System (ADS)

    Bhadri, P. R.; Majumder, A.; Morgan, C. J.; Pyne, G. J.; Zuccarello, M.; Jauch, E.; Wagner, K. R.; Clark, J. F.; Caffery, J., Jr.; Beyette, Fred R., Jr.

    2003-11-01

    A cerebral aneurysm is a weakened portion of an artery in the brain. When a cerebral aneurysm ruptures, a specific type of bleeding known as a subarachnoid hemorrhage (SAH) occurs. No test exists currently to screen people for the presence of an aneurysm. The diagnosis of a SAH is made after an aneurysm ruptures, and the literature indicates that nearly one-third of patients with a SAH are initially misdiagnosed and subjected to the risks associated with aneurysm re-rupture. For those individuals with a suspected SAH, a computerized tomography (CT) scan of the brain usually demonstrates evidence of the bleeding. However, in a considerable portion of people, the CT scan is unable to detect the blood that has escaped from the blood vessel. For circumstances when a SAH is suspected despite a normal CT scan, physicians make the diagnosis of SAH by performing a spinal tap. A spinal tap uses a needle to sample the cerebrospinal fluid (CSF) collected from the patient"s back; CSF is tainted with blood after the aneurysm ruptures. To distinguish between a common headache and a SAH, a fast and an effective solution is required. We describe the development of an effective detection system integrating hardware and a powerful software interface solution. Briefly, CSF from the patient is aspirated and excited with an appropriate wavelength of light. The software employs spectrophotometric analysis of the output spectra and lays the foundation for the development of portable and user-friendly equipment for detection of a ruptured cerebral aneurysm.

  18. Primary gastric rupture in 47 horses (1995–2011)

    PubMed Central

    Winfield, Laramie S.; Dechant, Julie E.

    2015-01-01

    The purpose of this retrospective case-control study was to identify factors associated with primary gastric rupture and to investigate if there were differences between etiologies of primary gastric rupture. Compared to the general colic population, Quarter horses were under-represented and Friesians and draft breeds were over-represented in 47 cases of primary gastric ruptures. Horses with primary gastric rupture typically presented with severe clinical and clinicopathological derangements. There were 24 idiopathic gastric ruptures, 20 gastric impaction associated ruptures, and 3 perforating gastric ulcers. Thoroughbred horses were over-represented in the idiopathic gastric rupture group compared to other breeds and etiologies. This study suggests the presence of important breed predispositions for development of gastric rupture. Further study is necessary to identify if these predispositions are associated with management factors or breed-specific disorders. PMID:26345205

  19. Spontaneous rupture of fetal hydronephrosis: case report.

    PubMed

    Kosus, A; Kosus, N; Duran, M; Turhan, N

    2011-08-01

    Hydronephrosis is the most common congenital anomaly observed with prenatal ultrasonography. Ureteropelvic junction obstruction (UPJO) is the most common cause of prenatal hydronephrosis. Spontaneous rupture has been reported in adults with severe hydronephrosis. There is no reported spontaneous rupture case in the fetus in the literature. A spontaneous ureteral rupture due to severe UPJO was reported in this case report. Prenatal ultrasound at 33 week gestation in a 21-year-old pregnant woman, revealed a female fetus with grade IV hydronephrosis of the right kidney, suggestive of a UPJO. During the follow-up at XXXVIII week, 5 cm cystic structure was not observed in right kidney. Mild ectasia was present in pelvicalyciel part which make us think about spontaneous rupture. Ultrasonographic examination after a week post-delivery revealed 15 mm pelvicalyciel ectasia on right side which persisted during the second control after 1 month. Vesicoureteral reflux was not detected during voiding cystourethrogram. Diuretic renography revealed loss of right renal function completely. Because there was not any complain or any clinical sign, surgery was not thought. Spontaneous follow-up was recommended. PMID:21959707

  20. An Uncommon Presentation of Breast Implant Rupture

    PubMed Central

    Watson, David I.; Dean, Nicola R.

    2016-01-01

    Summary: Late periprosthetic seroma has lately been concerning for breast implant-associated anaplastic large cell lymphoma. The authors present an uncommon presentation of breast implant rupture with a seroma and skin rash forming 2 years after insertion of the implant. PMID:27579243

  1. Star polymers rupture induced by constant forces

    NASA Astrophysics Data System (ADS)

    García, N. A.; Febbo, M.; Vega, D. A.; Milchev, A.

    2014-10-01

    In this work, we study the breakage process of an unknotted three-arm star-shaped polymer when it is pulled from its free ends by a constant force. The star polymer configuration is described through an array of monomers coupled by anharmonic bonds, while the rupture process is tracked in three-dimensional space by means of Langevin Molecular Dynamics simulations. The interaction between monomers is described by a Morse potential, while a Weeks-Chandler-Anderson energetic contribution accounts for the excluded volume interaction. We explore the effect of the molecular architecture on the distributions of rupture times over a broad interval of pulling forces and star configurations. It was found that the rupture time distribution of the individual star arms is strongly affected by the star configuration imposed by the pulling forces and the length of the arms. We also observed that for large pulling forces the rupture time distributions resemble the dominant features observed for linear polymer chains. The model introduced here provides the basic ingredients to describe the effects of tensile forces on stress-induced degradation of branched macromolecules and polymer networks.

  2. Active diaphragm rupture with laser beam irradiation

    NASA Astrophysics Data System (ADS)

    Takahashi, T.; Torikai, H.; Yang, Q. S.; Watanabe, K.; Sasoh, A.

    We performed shock tube operations with a layer of diaphragm being ruptured by laser beam irradiation. Mylar or Cellophane was examined as the diaphragm material. It has been demonstrated that shock tube can be operated with this new technique. The absorbed energy depends on the material and thickness of the diaphragm and is an important control parameter.

  3. D-Zero Cryostat Supplemental Rupture Disc

    SciTech Connect

    Mulholland, G.T.; /Fermilab

    1987-08-03

    The common relief and rupture disc vent line requires a double disc assembly with vented interspace for accurate disc burst pressures. The first disc must take pump and purge vacuum loading, but be set to operate at 110% of the MAWP, 18.3 psig (ASME code). The available solution is 18.3 psig with a burst tolerance of +/- psig. The interspace should be locally vented by a flow limiting vent valve to decouple the vent line backpressure from the vessel rupture disc. The second disc must take the worst case vent line backpressure, the steady state value found in D-Zero engineering note 3740.000-EN-63 with all three cryostats simultaneously venting at the fire condition into the 4-inch x 6-inch and 6-inch x 8-inch sections. This value is less than 2 psid. The maximum rupture value for the second disc must be less than the minimum rupture value for the first disc less 2 psid i.e. < 16.3.

  4. Primary obstructive megaureter with ruptured kidney.

    PubMed

    Chung, Shiu-Dong; Sun, Hsu-Dong; Yang, Den-Kai; Liao, Chun-Hou

    2009-01-01

    A 17-year-old boy presented to the emergency department for severe left flank pain and gross hematuria 1 hour after playing basketball without significant collision. Laboratory tests showed normal renal function and massive hematuria. Abdominal computed tomography scan disclosed a primary megaureter with ruptured kidney. We successfully treated him with ureteral stenting followed by endoscopic ureterotomy and ureteroneocystostomy. PMID:19041564

  5. Pancreatic pseudocyst rupture into the portal vein.

    PubMed

    Dawson, Brian C; Kasa, David; Mazer, Mark A

    2009-07-01

    A patient with a pancreatic pseudocyst rupture into the portal vein with a resultant noninfectious systemic inflammatory response syndrome and subsequent portal vein thrombosis diagnosed by computed tomography and ultrasonography is reported. A review of the existing English literature on this rare complication is also provided. PMID:19561436

  6. Traumatic rupture of the right subclavian artery

    PubMed Central

    Girdwood, Robert W.; Holden, Michael P.; Ionescu, Marian I.

    1972-01-01

    The case report of a patient who sustained a traumatic rupture of the right subclavian artery in a motor vehicle accident is presented. The preoperative diagnosis, surgical approach, postoperative management, and indications for angiography in traumatic lesions of the thoracic aorta and great vessels are discussed. The relevant literature is reviewed. Images PMID:5034604

  7. An Uncommon Presentation of Breast Implant Rupture.

    PubMed

    Koh, Eugene; Watson, David I; Dean, Nicola R

    2016-05-01

    Late periprosthetic seroma has lately been concerning for breast implant-associated anaplastic large cell lymphoma. The authors present an uncommon presentation of breast implant rupture with a seroma and skin rash forming 2 years after insertion of the implant. PMID:27579243

  8. Fatigue crack propagation analysis of plaque rupture.

    PubMed

    Pei, Xuan; Wu, Baijian; Li, Zhi-Yong

    2013-10-01

    Rupture of atheromatous plaque is the major cause of stroke or heart attack. Considering that the cardiovascular system is a classic fatigue environment, plaque rupture was treated as a chronic fatigue crack growth process in this study. Fracture mechanics theory was introduced to describe the stress status at the crack tip and Paris' law was used to calculate the crack growth rate. The effect of anatomical variation of an idealized plaque cross-section model was investigated. The crack initiation was considered to be either at the maximum circumferential stress location or at any other possible locations around the lumen. Although the crack automatically initialized at the maximum circumferential stress location usually propagated faster than others, it was not necessarily the most critical location where the fatigue life reached its minimum. We found that the fatigue life was minimum for cracks initialized in the following three regions: the midcap zone, the shoulder zone, and the backside zone. The anatomical variation has a significant influence on the fatigue life. Either a decrease in cap thickness or an increase in lipid pool size resulted in a significant decrease in fatigue life. Comparing to the previously used stress analysis, this fatigue model provides some possible explanations of plaque rupture at a low stress level in a pulsatile cardiovascular environment, and the method proposed here may be useful for further investigation of the mechanism of plaque rupture based on in vivo patient data. PMID:23897295

  9. Source rupture process of the 2011 Fukushima-ken Hamadori earthquake: how did the two subparallel faults rupture?

    NASA Astrophysics Data System (ADS)

    Tanaka, Miho; Asano, Kimiyuki; Iwata, Tomotaka; Kubo, Hisahiko

    2014-12-01

    The 2011 Fukushima-ken Hamadori earthquake (MW 6.6) occurred about a month after the 2011 Great Tohoku earthquake (MW 9.0), and it is thought to have been induced by the 2011 Tohoku earthquake. After the 2011 Hamadori earthquake, two subparallel faults (the Itozawa and Yunodake faults) were identified by field surveys. The hypocenter was located nearby the Itozawa fault, and it is probable that the Itozawa fault ruptured before the Yunodake fault rupture. Here, we estimated the source rupture process of the 2011 Hamadori earthquake using a model with two subparallel faults based on strong motion data. The rupture starting point and rupture delay time of the Yunodake fault were determined based on Akaike's Bayesian Information Criterion (ABIC). The results show that the Yunodake fault started to rupture from the northern deep point 4.5 s after the Itozawa fault started to rupture. The estimated slip distribution in the shallow part is consistent with the surface slip distribution identified by field surveys. Time-dependent Coulomb failure function changes (ΔCFF) were calculated using the stress change from the Itozawa fault rupture in order to evaluate the effect of the rupture on the Yunodake fault. The ΔCFF is positive at the rupture starting point of the Yunodake fault 4.5 s after the Itozawa fault started to rupture; therefore, it is concluded that during the 2011 Hamadori earthquake, the Yunodake fault rupture was triggered by the Itozawa fault rupture.

  10. Traumatic rupture of the aortic isthmus: program of selective management.

    PubMed

    Pate, J W; Gavant, M L; Weiman, D S; Fabian, T C

    1999-01-01

    Two hypotheses were investigated: (1) helical computed tomography (CT) of the chest on victims of decelerating trauma can yield a diagnosis of, or "rule out," a traumatic rupture of the aorta (TRA) without the need for an aortogram; and (2) selective delay of aortic repair can be safely accomplished through a medical management protocol. Screening helical CT examinations were done on 6169 victims of blunt thoracic trauma; 47 were found to have TRA; in 8, indirect but nondiagnostic findings not clarified by an aortogram led to surgical exploration. The sensitivity of helical CT was higher than that of aortograms, and a "normal" helical CT scan was never associated with a proved TRA. It is estimated that the use of helical CT has resulted in at least a 40% to 50% decrease in the need for aortograms, in addition to yielding rapid, noninvasive valuable information about other injuries. Drugs (beta-blockers +/- vasodilators) to decrease the stress in the aortic wall were used in 93 patients when the diagnosis was suspected and were continued as necessary through the evaluation, stabilization, and until the aorta was cross-clamped at operation. Elective, delayed operation was done between 2 days and 25 months in 15 patients who were deemed to be excessive risks for emergency aortic repair; there were 2 deaths (13. 3%). Eleven patients never had aortic repair. No patient maintained on this protocol, whether repaired emergently, electively, or not at all, developed free rupture of the periaortic hematoma and death from TRA. PMID:9841764

  11. Ruptured Pseudoaneurysm after Gamma Knife Surgery for Vestibular Schwannoma

    PubMed Central

    MURAKAMI, Mamoru; KAWARABUKI, Kentaro; INOUE, Yasuo; OHTA, Tsutomu

    2016-01-01

    Ruptured aneurysms of anterior inferior cerebellar artery (AICA) after radiotherapy for vestibular schwannoma (VS) are rare, and no definite treatment has been established for distal AICA pseudoaneurysms. We describe a 61-year-old man who underwent Gamma Knife surgery (GKS) for left VS. Follow-up magnetic resonance imaging (MRI) revealed partial regression of the tumor. Twelve years after GKS, he suffered from subarachnoid hemorrhage. Initial angiogram showed no vascular lesions; second left vertebral angiogram, 10 days after admission, demonstrated a pseudoaneurysm in the lateral pontine segment of the left AICA. The proximal portion of the AICA was occluded by a coil. Postoperative MRI revealed an infarction on the left side of the pons and brachium pontis. Although the patient suffered from mild postoperative cerebellar ataxia and facial and abducens nerve palsy, he was discharged 1 month postoperatively requiring no assistance with activities of daily living. Twelve months later, he recovered satisfactorily with a modified Rankin Scale grade of 1, and no recanalization of the aneurysm was found on MR angiography. Endovascular parent artery occlusion for ruptured aneurysms at distal AICA carries the risk of brain stem infarction, but should be considered when no other option is available such as after radiotherapy for VS. PMID:26667081

  12. Unfolding the mechanism of the AAA+ unfoldase VAT by a combined cryo-EM, solution NMR study.

    PubMed

    Huang, Rui; Ripstein, Zev A; Augustyniak, Rafal; Lazniewski, Michal; Ginalski, Krzysztof; Kay, Lewis E; Rubinstein, John L

    2016-07-19

    The AAA+ (ATPases associated with a variety of cellular activities) enzymes play critical roles in a variety of homeostatic processes in all kingdoms of life. Valosin-containing protein-like ATPase of Thermoplasma acidophilum (VAT), the archaeal homolog of the ubiquitous AAA+ protein Cdc48/p97, functions in concert with the 20S proteasome by unfolding substrates and passing them on for degradation. Here, we present electron cryomicroscopy (cryo-EM) maps showing that VAT undergoes large conformational rearrangements during its ATP hydrolysis cycle that differ dramatically from the conformational states observed for Cdc48/p97. We validate key features of the model with biochemical and solution methyl-transverse relaxation optimized spectroscopY (TROSY) NMR experiments and suggest a mechanism for coupling the energy of nucleotide hydrolysis to substrate unfolding. These findings illustrate the unique complementarity between cryo-EM and solution NMR for studies of molecular machines, showing that the structural properties of VAT, as well as the population distributions of conformers, are similar in the frozen specimens used for cryo-EM and in the solution phase where NMR spectra are recorded. PMID:27402735

  13. Improved Structures of Full-Length P97, An AAA ATPase: Implications for Mechanisms of Nucleotide-Dependent Conformational Change

    SciTech Connect

    Davies, J.M.; Brunger, A.T.; Weis, W.I.

    2009-05-14

    The ATPases associated with various cellular activities (AAA) protein p97 has been implicated in a variety of cellular processes, including endoplasmic reticulum-associated degradation and homotypic membrane fusion. p97 belongs to a subgroup of AAA proteins that contains two nucleotide binding domains, D1 and D2. We determined the crystal structure of D2 at 3.0 {angstrom} resolution. This model enabled rerefinement of full-length p97 in different nucleotide states against previously reported low-resolution diffraction data to significantly improved R values and Ramachandran statistics. Although the overall fold remained similar, there are significant improvements, especially around the D2 nucleotide binding site. The rerefinement illustrates the importance of knowledge of high-resolution structures of fragments covering most of the whole molecule. The structures suggest that nucleotide hydrolysis is transformed into larger conformational changes by pushing of one D2 domain by its neighbor in the hexamer, and transmission of nucleotide-state information through the D1-D2 linker to displace the N-terminal, effector binding domain.

  14. The AAA ATPase Vps4 Plays Important Roles in Candida albicans Hyphal Formation and is Inhibited by DBeQ.

    PubMed

    Zhang, Yahui; Li, Wanjie; Chu, Mi; Chen, Hengye; Yu, Haoyuan; Fang, Chaoguang; Sun, Ningze; Wang, Qiming; Luo, Tian; Luo, Kaiju; She, Xueping; Zhang, Mengqian; Yang, Dong

    2016-06-01

    Candida albicans is an opportunistic human pathogen, and its pathogenicity is associated with hyphal formation. Previous studies have shown that at neutral-to-alkaline pH, hyphal growth is dependent on the Rim101 pathway whose activation requires Snf7, a member of the ESCRT system. In this work, we described the purification and characterization of the C. albicans Vps4, an AAA ATPase required for recycling of the ESCRTs. Its role on hyphal growth has been investigated. Our data suggest deletion of Vps4 decreases overall hyphal growth at pH 7 and increases the growth of multiple hyphae induced by serum, which indicates that the ESCRTs may make a Rim101-independent contribution to hyphal growth. Furthermore, DBeQ, an inhibitor of the AAA ATPase p97, was shown to inhibit the ATPase activity of Vps4 with an IC50 of about 11.5 μM. To a less degree, it also inhibits hyphal growth. Our work may provide a new strategy to control C. albicans infection. PMID:26700222

  15. Nucleotide binding and allosteric modulation of the second AAA+ domain of ClpB probed by transient kinetic studies.

    PubMed

    Werbeck, Nicolas D; Kellner, Julian N; Barends, Thomas R M; Reinstein, Jochen

    2009-08-01

    The bacterial AAA+ chaperone ClpB provides thermotolerance by disaggregating aggregated proteins in collaboration with the DnaK chaperone system. Like many other AAA+ proteins, ClpB is believed to act as a biological motor converting the chemical energy of ATP into molecular motion. ClpB has two ATPase domains, NBD1 and NBD2, on one polypeptide chain. The functional unit of ClpB is a homohexameric ring, with a total of 12 potential nucleotide binding sites. Previously, two separate constructs, one each containing NBD1 or NBD2, have been shown to form a functional complex with chaperone activity when mixed. Here we aimed to elucidate the nucleotide binding properties of the ClpB complex using pre-steady state kinetics and fluorescent nucleotides. For this purpose, we first disassembled the complex and characterized in detail the binding kinetics of a construct comprising NBD2 and the C-terminal domain of ClpB. The monomeric construct bound nucleotides very tightly. ADP bound 2 orders of magnitude more tightly than ATP; this difference in binding affinity resulted almost exclusively from different dissociation rate constants. The nucleotide binding properties of NBD2 changed when this construct was complemented with a construct comprising NBD1 and the middle domain. Our approach shows how complex formation can influence the binding properties of the individual domains and allows us to assign nucleotide binding features of this highly complex, multimeric enzyme to specific domains. PMID:19594134

  16. Recent Advances in Deciphering the Structure and Molecular Mechanism of the AAA+ ATPase N-Ethylmaleimide-Sensitive Factor (NSF).

    PubMed

    Zhao, Minglei; Brunger, Axel T

    2016-05-01

    N-ethylmaleimide-sensitive factor (NSF), first discovered in 1988, is a key factor for eukaryotic trafficking, including protein and hormone secretion and neurotransmitter release. It is a member of the AAA+ family (ATPases associated with diverse cellular activities). NSF disassembles soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complexes in conjunction with soluble N-ethylmaleimide-sensitive factor attachment protein (SNAP). Structural studies of NSF and its complex with SNAREs and SNAPs (known as 20S supercomplex) started about 20years ago. Crystal structures of individual N and D2 domains of NSF and low-resolution electron microscopy structures of full-length NSF and 20S supercomplex have been reported over the years. Nevertheless, the molecular architecture of the 20S supercomplex and the molecular mechanism of NSF-mediated SNARE complex disassembly remained unclear until recently. Here we review recent atomic-resolution or near-atomic resolution structures of NSF and of the 20S supercomplex, as well as recent insights into the molecular mechanism and energy requirements of NSF. We also compare NSF with other known AAA+ family members. PMID:26546278

  17. Ruptured rectal duplication with urogenital abnormality: Unusual presentation

    PubMed Central

    Solanki, Shailesh; Babu, M Narendra; Jadhav, Vinay; Shankar, Gowri; Santhanakrishnan, Ramesh

    2015-01-01

    Rectal duplication (RD) accounts for 5% of alimentary tract duplication. A varied presentation and associated anomalies have been described in the literature. Antenatal rupture of the RD is very rare. We present an unusual case of a ruptured RD associated with urogenital abnormalities in newborn male. We are discussing diagnosis, embryology, management and literature review of ruptured RD. PMID:25552833

  18. Rupture dimensions and rupture processes of fluid-induced microcracks in salt rock

    NASA Astrophysics Data System (ADS)

    Dahm, T.

    2001-08-01

    We developed and applied a simple empirical Green function method to study induced microcracks observed during hydraulic fracturing experiments in salt rock. Either unidirectional ruptures on rectangular faults or allround ruptures on elliptical faults are tested to explain the observed directivity effects in body-wave amplitude spectra. Mostly, the rectangular rupture model and horizontal fault planes are favored. The average rupture lengths are between 15 and 27 mm, the average rupture durations between 14 and 26 μs. Small average rupture velocities of 30% of the S-wave velocity of the rock are indicated. The dispersive low-frequency coda-waves present in the data look similar to coda-waves observed during other hydraulic fracturing experiments and to long-period events from some volcanoes, which have been explained by the resonance of a fluid-filled crack. The radiation pattern of first motion amplitudes of most events is dominated by a dip-slip double-couple indicating slip on horizontal or vertical planes. We cannot distinguish whether the observed low-frequency coda-waves are influenced by a source effect or by a possible sensor-borehole coupling. However, a simple method using Gauss filter at different center frequencies and relocation is tested to analyze the low-frequency coda-waves in terms of source models.

  19. Risk.

    PubMed

    Cole, Stephen R; Hudgens, Michael G; Brookhart, M Alan; Westreich, Daniel

    2015-02-15

    The epidemiologist primarily studies transitions between states of health and disease. The purpose of the present article is to define a foundational parameter for such studies, namely risk. We begin simply and build to the setting in which there is more than 1 event type (i.e., competing risks or competing events), as well as more than 1 treatment or exposure level of interest. In the presence of competing events, the risks are a set of counterfactual cumulative incidence functions for each treatment. These risks can be depicted visually and summarized numerically. We use an example from the study of human immunodeficiency virus to illustrate concepts. PMID:25660080

  20. Simultaneous rupture of the quadriceps tendon with contralateral rupture of the patellar tendon in an otherwise healthy athlete.

    PubMed Central

    Munshi, N I; Mbubaegbu, C E

    1996-01-01

    A case of a healthy athlete with simultaneous rupture of quadriceps tendon and rupture of the contralateral patella tendon is reported. Both tendons rupturing in the same patient is rare and this is the first reported case in a previously healthy person. Different mechanisms are implicated in the different ruptures. The rarity is because the simultaneous presence of contributory factors for either injury in the same person is uncommon. Images Fig. 2 PMID:8799608

  1. Rupture Paths in Kappa-Maps: Quantitative Insights on Heterogeneous Earthquake Ruptures From Energy Arguments.

    NASA Astrophysics Data System (ADS)

    Ampuero, J.; Ripperger, J.; Mai, M.

    2005-12-01

    Earthquake rupture is a notoriously complex process, at all observable scales. Although heterogeneities of strength and initial stress contribute to this rupture complexity, a systematic approach to quantify their effect has not yet been attempted. For instance, little is known about the relation between the final size of an earthquake and the statistical properties of initial strength excess fields. Canonical cases of dynamic rupture (e.g. uniform initial stress and friction properties), can be characterized by two non-dimensional numbers: the S-parameter (ratio of strength excess to stress drop) and the Kappa-parameter (ratio of static energy release rate to fracture energy, Madariaga and Olsen, 2000). The latter was introduced as a global parameter, involving the fault depth or asperity size as the fundamental scale. However, because faults contain heterogeneities at all scales it is not clear how a single scale-length may be relevant to define Kappa. We define here a scale-dependent Kappa-map, based on classical energy concepts in fracture mechanics. In 2D these maps can be defined exactly, and their efficient computation is implemented as a series of FFT-convolutions, by scaled analytical filters related to stress intensity factor weight functions. For given heterogeneous stress drop and fracture energy, such Kappa-maps are useful to predict nucleation properties and final moment, as we illustrate through increasingly complex examples complemented by dynamic rupture simulations. Other properties that can be derived from the 2D Kappa-maps, with additional assumptions, include radiated energy and rupture directivity. In 3D, the shape of the rupture front is unknown a priori and the energy release rate G might be non-uniform along the front. We therefore propose an approximate definition of Kappa in which G is estimated on circular patches. Comparisons with 3D dynamic rupture simulations on highly heterogeneous initial stress fields show that the final moment can

  2. Dynamic Rupture Processes during Laboratory Earthquakes

    NASA Astrophysics Data System (ADS)

    Passelègue, F. X.; Schubnel, A.; Nielsen, S. B.; Bhat Suresh, H.; Madariaga, R. I.

    2014-12-01

    Since the proposal by Brace and Byerlee [1966] that the mechanism of stick-slip is similar to earthquakes, many experimental studies have been conducted in order to improve the understanding of rupture mechanics. Here, we report the results of macroscopic stick-slip events in saw-cut samples deformed under controlled upper crustal stress conditions in the laboratory. Experiments were conducted under triaxial laoding (σ1>σ2=σ3) at confining pressures ranging from 10 to 100 MPa. Usual a dual gain system, a high frequency monitoring array recorded the microseismicity during stick-slip sequences and the particle accelerations during macroscopic instabilities. While strain, stress and axial shortening were measured until 10 Hz sampling rate, we also recorded for the first time the dynamic stress changes during macroscopic rupture using dynamic strain gages located close to the fault plane (10 MHz sampling rate). We show that increasing the normal stress acting on the fault plane (i) increases the intensity of foreshock activity prior to the main rupture, (ii) increases the friction along the fault plane, (iii) increases the seismic slip, and (iv) induces the transition from sub-Rayleigh to supershear ruptures [Passelègue et al., 2013]. In addition, after demonstrating that our stick-slip instabilities exhibit a purely slip weakening behavior, we estimated the rupture processes parameters including the size of the breakdown zone (R), the slip-weakening distance (Dc), the energy rate (F) and the fracture energy (G). We compare our results with linear elastic fracture mechanics and previous experimental studies. Finally, the dynamic stress drop is almost complete at high normal stresses with dynamic friction drop ranging from 0.4 to 0.6. These results are consistent with the onset of melting, which was confirmed by our post mortem microstructural analysis (XRD, SEM, TEM). These results show that weakening mechanisms are activated after only 80 μm of slip, suggesting

  3. SORD: A New Rupture Dynamics Modeling Code

    NASA Astrophysics Data System (ADS)

    Ely, G.; Minster, B.; Day, S.

    2005-12-01

    We report on our progress in validating our rupture dynamics modeling code, capable of dealing with nonplanar faults and surface topography. The method uses a "mimetic" approach to model spontaneous rupture on a fault within a 3D isotropic anelastic solid, wherein the equations of motion are approximated with a second order Support-Operator method on a logically rectangular mesh. Grid cells are not required to be parallelepipeds, however, so that non-rectangular meshes can be supported to model complex regions. However, for areas in the mesh which are in fact rectangular, the code uses a streamlined version of the algorithm that takes advantage of the simplifications of the operators in such areas. The fault itself is modeled using a double node technique, and the rheology on the fault surface is modeled through a slip-weakening, frictional, internal boundary condition. The Support Operator Rupture Dynamics (SORD) code, was prototyped in MATLAB, and all algorithms have been validated against known (including analytical solutions, eg Kostrov, 1964) solutions or previously validated solutions. This validation effort is conducted in the context of the SCEC Dynamic Rupture model validation effort led by R. Archuleta and R. Harris. Absorbing boundaries at the model edges are handled using the perfectly matched layers method (PML) (Olsen & Marcinkovich, 2003). PML is shown to work extremely well on rectangular meshes. We show that our implementation is also effective on non-rectangular meshes under the restriction that the boundary be planar. For validation of the model we use a variety of test cases using two types of meshes: a rectangular mesh and skewed mesh. The skewed mesh amplifies any biases caused by the Support-Operator method on non-rectangular elements. Wave propagation and absorbing boundaries are tested with a spherical wave source. Rupture dynamics on a planar fault are tested against (1) a Kostrov analytical solution, (2) data from foam rubber scale models

  4. Isolated Total Rupture of Extraocular Muscles.

    PubMed

    Chen, Jingchang; Kang, Ying; Deng, Daming; Shen, Tao; Yan, Jianhua

    2015-09-01

    Total rupture of extraocular muscles is an infrequent clinical finding. Here we conducted this retrospective study to evaluate their causes of injury, clinical features, imaging, surgical management, and final outcomes in cases of isolated extraocular muscle rupture at a tertiary center in China. Thirty-six patients were identified (24 men and 12 women). Mean age was 34 years (range 2-60). The right eye was involved in 21 patients and the left 1 in 15. A sharp object or metal hook was the cause of this lesion in 16 patients, sinus surgery in 14 patients, traffic accident in 3 patients, orbital surgery in 2 patients, and conjunctive tumor surgery in 1 patient. The most commonly involved muscles were medial (18 patients) and inferior rectus muscles (13 patients). The function of the ruptured muscles revealed a scale of -3 to -4 defect of ocular motility and the amount of deviation in primary position varied from 10 to 140 PD (prism diopter). Computerized tomography (CT) confirmed the presence of ruptured muscles. An end-to-end muscle anastomosis was performed and 3 to 5 mm of muscle was resected in 23 patients. When the posterior border of the injured muscle could not be identified (13 patients), a partial tendon transposition was performed, together with recession of the antagonist in most patients, whereas a recession of the antagonist muscle plus a resection of the involved muscle with or without nasal periosteal fixation was performed in the remaining patients. After an average of 16.42 months of follow-up an excellent result was achieved in 23 patients and results of 13 patients were considered as a failure. In most patients, the posterior border of the ruptured muscle can be identified and an early surgery can be performed to restore function. Alternatively, a partial tendon transposition should be performed. When muscular rupture is suspected, an early orbital CT is required to confirm this possibility, which can then verify the necessity for an early surgical

  5. Isolated Total Rupture of Extraocular Muscles

    PubMed Central

    Chen, Jingchang; Kang, Ying; Deng, Daming; Shen, Tao; Yan, Jianhua

    2015-01-01

    Abstract Total rupture of extraocular muscles is an infrequent clinical finding. Here we conducted this retrospective study to evaluate their causes of injury, clinical features, imaging, surgical management, and final outcomes in cases of isolated extraocular muscle rupture at a tertiary center in China. Thirty-six patients were identified (24 men and 12 women). Mean age was 34 years (range 2–60). The right eye was involved in 21 patients and the left 1 in 15. A sharp object or metal hook was the cause of this lesion in 16 patients, sinus surgery in 14 patients, traffic accident in 3 patients, orbital surgery in 2 patients, and conjunctive tumor surgery in 1 patient. The most commonly involved muscles were medial (18 patients) and inferior rectus muscles (13 patients). The function of the ruptured muscles revealed a scale of −3 to −4 defect of ocular motility and the amount of deviation in primary position varied from 10 to 140 PD (prism diopter). Computerized tomography (CT) confirmed the presence of ruptured muscles. An end-to-end muscle anastomosis was performed and 3 to 5 mm of muscle was resected in 23 patients. When the posterior border of the injured muscle could not be identified (13 patients), a partial tendon transposition was performed, together with recession of the antagonist in most patients, whereas a recession of the antagonist muscle plus a resection of the involved muscle with or without nasal periosteal fixation was performed in the remaining patients. After an average of 16.42 months of follow-up an excellent result was achieved in 23 patients and results of 13 patients were considered as a failure. In most patients, the posterior border of the ruptured muscle can be identified and an early surgery can be performed to restore function. Alternatively, a partial tendon transposition should be performed. When muscular rupture is suspected, an early orbital CT is required to confirm this possibility, which can then verify the necessity for

  6. A Geodesics-Based Surface Parameterization to Assess Aneurysm Progression.

    PubMed

    Phan, Ly; Courchaine, Katherine; Azarbal, Amir; Vorp, David; Grimm, Cindy; Rugonyi, Sandra

    2016-05-01

    Abdominal aortic aneurysm (AAA) intervention and surveillance is currently based on maximum transverse diameter, even though it is recognized that this might not be the best strategy. About 10% of patients with small AAA transverse diameters, for whom intervention is not considered, still rupture; while patients with large AAA transverse diameters, for whom intervention would have been recommended, have stable aneurysms that do not rupture. While maximum transverse diameter is easy to measure and track in clinical practice, one of its main drawbacks is that it does not represent the whole AAA and rupture seldom occurs in the region of maximum transverse diameter. By following maximum transverse diameter alone clinicians are missing information on the shape change dynamics of the AAA, and clues that could lead to better patient care. We propose here a method to register AAA surfaces that were obtained from the same patient at different time points. Our registration method could be used to track the local changes of the patient-specific AAA. To achieve registration, our procedure uses a consistent parameterization of the AAA surfaces followed by strain relaxation. The main assumption of our procedure is that growth of the AAA occurs in such a way that surface strains are smoothly distributed, while regions of small and large surface growth can be differentiated. The proposed methodology has the potential to unravel different patterns of AAA growth that could be used to stratify patient risks. PMID:27003915

  7. A rare case of occult splenic rupture after left pneumonectomy

    PubMed Central

    Acharya, Metesh N.; George, Robert S; Loubani, Mahmoud

    2016-01-01

    Cardiopulmonary resuscitation (CPR) techniques are now well-established and play a crucial role in improving survival in cardiac arrest. Recognized complications associated with CPR include injury to the upper abdominal viscera, including the liver, stomach and spleen. We present a rare case of occult splenic rupture following cardiac arrest in a 63-year-old male immediately after left pneumonectomy. We discuss potential mechanisms predisposing the spleen to injury in this case, and highlight the difficulty of promptly identifying such a traumatic injury within the confines of a cardiac arrest scenario. Clinicians should be aware that anatomical changes following thoracic surgery may render the intra-abdominal viscera at increased risk of injury following CPR. PMID:27190201

  8. Endoport-Assisted Microsurgical Treatment of a Ruptured Periventricular Aneurysm.

    PubMed

    Chen, Ching-Jen; Caruso, James; Starke, Robert M; Ding, Dale; Buell, Thomas; Crowley, R Webster; Liu, Kenneth C

    2016-01-01

    Background and Importance. Ruptured periventricular aneurysms in patients with moyamoya disease represent challenging pathologies. The most common methods of treatment include endovascular embolization and microsurgical clipping. However, rare cases arise in which the location and anatomy of the aneurysm make these treatment modalities particularly challenging. Clinical Presentation. We report a case of a 34-year-old female with moyamoya disease who presented with intraventricular hemorrhage. CT angiography and digital subtraction angiography revealed an aneurysm located in the wall of the atrium of the right lateral ventricle. Distal endovascular access was not possible, and embolization risked the sacrifice of arteries supplying critical brain parenchyma. Using the BrainPath endoport system, the aneurysm was able to be accessed. Since the fusiform architecture of the aneurysm prevented clip placement, the aneurysm was ligated with electrocautery. Conclusion. We demonstrate the feasibility of endoport-assisted approach for minimally invasive access and treatment of uncommon, distally located aneurysms. PMID:27195160

  9. Endoport-Assisted Microsurgical Treatment of a Ruptured Periventricular Aneurysm

    PubMed Central

    Chen, Ching-Jen; Caruso, James; Buell, Thomas; Crowley, R. Webster; Liu, Kenneth C.

    2016-01-01

    Background and Importance. Ruptured periventricular aneurysms in patients with moyamoya disease represent challenging pathologies. The most common methods of treatment include endovascular embolization and microsurgical clipping. However, rare cases arise in which the location and anatomy of the aneurysm make these treatment modalities particularly challenging. Clinical Presentation. We report a case of a 34-year-old female with moyamoya disease who presented with intraventricular hemorrhage. CT angiography and digital subtraction angiography revealed an aneurysm located in the wall of the atrium of the right lateral ventricle. Distal endovascular access was not possible, and embolization risked the sacrifice of arteries supplying critical brain parenchyma. Using the BrainPath endoport system, the aneurysm was able to be accessed. Since the fusiform architecture of the aneurysm prevented clip placement, the aneurysm was ligated with electrocautery. Conclusion. We demonstrate the feasibility of endoport-assisted approach for minimally invasive access and treatment of uncommon, distally located aneurysms. PMID:27195160

  10. A rare case of occult splenic rupture after left pneumonectomy.

    PubMed

    Acharya, Metesh N; George, Robert S; Loubani, Mahmoud

    2016-01-01

    Cardiopulmonary resuscitation (CPR) techniques are now well-established and play a crucial role in improving survival in cardiac arrest. Recognized complications associated with CPR include injury to the upper abdominal viscera, including the liver, stomach and spleen. We present a rare case of occult splenic rupture following cardiac arrest in a 63-year-old male immediately after left pneumonectomy. We discuss potential mechanisms predisposing the spleen to injury in this case, and highlight the difficulty of promptly identifying such a traumatic injury within the confines of a cardiac arrest scenario. Clinicians should be aware that anatomical changes following thoracic surgery may render the intra-abdominal viscera at increased risk of injury following CPR. PMID:27190201

  11. Rupture Process During the 2015 Illapel, Chile Earthquake: Zigzag-Along-Dip Rupture Episodes

    NASA Astrophysics Data System (ADS)

    Okuwaki, Ryo; Yagi, Yuji; Aránguiz, Rafael; González, Juan; González, Gabriel

    2016-04-01

    We constructed a seismic source model for the 2015 M W 8.3 Illapel, Chile earthquake, which was carried out with the kinematic waveform inversion method adopting a novel inversion formulation that takes into account the uncertainty in the Green's function, together with the hybrid backprojection method enabling us to track the spatiotemporal distribution of high-frequency (0.3-2.0 Hz) sources at high resolution by using globally observed teleseismic P-waveforms. A maximum slip amounted to 10.4 m in the shallow part of the seismic source region centered 72 km northwest of the epicenter and generated a following tsunami inundated along the coast. In a gross sense, the rupture front propagated almost unilaterally to northward from the hypocenter at <2 km/s, however, in detail the spatiotemporal slip distribution also showed a complex rupture propagation pattern: two up-dip rupture propagation episodes, and a secondary rupture episode may have been triggered by the strong high-frequency radiation event at the down-dip edge of the seismic source region. High-frequency sources tends to be distributed at deeper parts of the slip area, a pattern also documented in other subduction zone megathrust earthquakes that may reflect the heterogeneous distribution of fracture energy or stress drop along the fault. The weak excitation of high-frequency radiation at the termination of rupture may represent the gradual deceleration of rupture velocity at the transition zone of frictional property or stress state between the megathrust rupture zone and the swarm area.

  12. Stopping of earthquake ruptures at dilational fault jogs

    NASA Astrophysics Data System (ADS)

    Sibson, Richard H.

    1985-07-01

    Palaeoseismic studies over the past several years have indicated that segments of certain major faults tend to rupture at fairly regular intervals in characteristic earthquakes of about the same size1. This implies the presence of local structural controls which govern the nucleation and stopping of ruptures. Understanding rupture arrest is important, not only because it governs the size of characteristic earthquakes, but also because deceleration of ruptures results in the radiation of high-frequency energy leading to strong ground motion2. I show here that rapid opening of linking extensional fracture systems to allow passage of earthquake ruptures through dilational fault jogs in fluid-saturated crusts is opposed by transient suctional forces induced near the rupture tips3. Rupture arrest may then be followed by delayed slip transfer as fluid pressures re-equilibrate by diffusion.

  13. Brittle dynamic damage due to earthquake rupture

    NASA Astrophysics Data System (ADS)

    Bhat, Harsha; Thomas, Marion

    2016-04-01

    The micromechanical damage mechanics formulated by Ashby and Sammis, 1990, and generalized by Deshpande and Evans 2008 has been extended to allow for a more generalized stress state and to incorporate an experimentally motivated new crack growth (damage evolution) law that is valid over a wide range of loading rates. This law is sensitive to both the crack tip stress field and its time derivative. Incorporating this feature produces additional strain-rate sensitivity in the constitutive response. The model is also experimentally verified by predicting the failure strength of Dionysus-Pentelicon marble over wide range of strain rates. We then implement this constitutive response to understand the role of dynamic brittle off-fault damage on earthquake ruptures. We show that off-fault damage plays an important role in asymmetry of rupture propagation and is a source of high-frequency ground motion in the near source region.

  14. Recurrent spontaneous scleral rupture in Marfan's syndrome.

    PubMed

    Turaga, Kiranmaye; Senthil, Sirisha; Jalali, Subhadra

    2016-01-01

    The ocular manifestations of Marfan's syndrome (MS) range from ectopia lentis, microspherophakia, myopia, glaucoma and retinal detachment. Spontaneous scleral rupture is a rare complication and recurrent scleral perforation is extremely rare. We report a rare case of a 26-year-old male with MS who had sequential recurrent spontaneous scleral rupture which required surgical repair. He suffered from a similar problem 4 years later in both eyes in a different location, with overlying thin cystic blebs and hypotony maculopathy. Surgical repair with preserved scleral donor patch graft and conjunctival autograft in one eye, and conjunctival advancement in the other eye was performed. This helped stabilise the eyes, and resulted in complete visual recovery in both eyes. PMID:27199441

  15. Creep rupture behavior of Stirling engine materials

    NASA Technical Reports Server (NTRS)

    Titran, R. H.; Scheuerman, C. M.; Stephens, J. R.

    1985-01-01

    The automotive Stirling engine, being investigated jointly by the Department of Energy and NASA Lewis as an alternate to the internal combustion engine, uses high-pressure hydrogen as the working fluid. The long-term effects of hydrogen on the high temperature strength properties of materials is relatively unknown. This is especially true for the newly developed low-cost iron base alloy NASAUT 4G-A1. This iron-base alloy when tested in air has creep-rupture strengths in the directionally solidified condition comparable to the cobalt base alloy HS-31. The equiaxed (investment cast) NASAUT 4G-A1 has superior creep-rupture to the equiaxed iron-base alloy XF-818 both in air and 15 MPa hydrogen.

  16. Liquid salt environment stress-rupture testing

    DOEpatents

    Ren, Weiju; Holcomb, David E.; Muralidharan, Govindarajan; Wilson, Dane F.

    2016-03-22

    Disclosed herein are systems, devices and methods for stress-rupture testing selected materials within a high-temperature liquid salt environment. Exemplary testing systems include a load train for holding a test specimen within a heated inert gas vessel. A thermal break included in the load train can thermally insulate a load cell positioned along the load train within the inert gas vessel. The test specimen can include a cylindrical gage portion having an internal void filled with a molten salt during stress-rupture testing. The gage portion can have an inner surface area to volume ratio of greater than 20 to maximize the corrosive effect of the molten salt on the specimen material during testing. Also disclosed are methods of making a salt ingot for placement within the test specimen.

  17. SU-E-T-137: Dosimetric Validation for Pinnacle, Acuros, AAA, and Brainlab Algorithms with Induced Inhomogenieties

    SciTech Connect

    Lopez, P; Tambasco, M; LaFontaine, R; Burns, L

    2014-06-01

    Purpose: To compare the dosimetric accuracy of the Eclipse 11.0 Acuros XB and Anisotropic Analytical Algorithm (AAA), Pinnacle-3 9.2 Collapsed Cone Convolution, and the iPlan 4.1 Monte Carlo (MC) and Pencil Beam (PB) algorithms using measurement as the gold standard. Methods: Ion chamber and diode measurements were taken for 6, 10, and 18 MV beams in a phantom made up of slab densities corresponding to solid water, lung, and bone. The phantom was setup at source-to-surface distance of 100 cm, and the field sizes were 3.0 × 3.0, 5.0 × 5.0, and 10.0 × 10.0 cm2. Data from the planning systems were computed along the central axis of the beam. The measurements were taken using a pinpoint chamber and edge diode for interface regions. Results: The best agreement between data from the algorithms and our measurements occurs away from the slab interfaces. For the 6 MV beam, iPlan 4.1 MC software performs the best with 1.7% absolute average percent difference from measurement. For the 10 MV beam, iPlan 4.1 PB performs the best with 2.7% absolute average percent difference from measurement. For the 18 MV beam, Acuros performs the best with 2.0% absolute average percent difference from measurement. It is interesting to note that the steepest drop in dose occurred the at lung heterogeneity-solid water interface of the18 MV, 3.0 × 3.0 cm2 field size setup. In this situation, Acuros and AAA performed best with an average percent difference within −1.1% of measurement, followed by iPlan 4.1 MC, which was within 4.9%. Conclusion: This study shows that all of the algorithms perform reasonably well in computing dose in a heterogeneous slab phantom. Moreover, Acuros and AAA perform particularly well at the lung-solid water interfaces for higher energy beams and small field sizes.

  18. Megakaryocyte rupture for acute platelet needs

    PubMed Central

    Stritt, Simon

    2015-01-01

    Circulating platelets were thought to arise solely from the protrusion and fragmentation of megakaryocyte cytoplasm. Now, Nishimura et al. (2015. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201410052) show that platelet release from megakaryocytes can be induced by interleukin-1α (IL-1α) via a new rupture mechanism, which yields higher platelet numbers, occurs independently of the key regulator of megakaryopoiesis thrombopoietin, and may occur during situations of acute platelet need. PMID:25963815

  19. Megakaryocyte rupture for acute platelet needs.

    PubMed

    Nieswandt, Bernhard; Stritt, Simon

    2015-05-11

    Circulating platelets were thought to arise solely from the protrusion and fragmentation of megakaryocyte cytoplasm. Now, Nishimura et al. (2015. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201410052) show that platelet release from megakaryocytes can be induced by interleukin-1α (IL-1α) via a new rupture mechanism, which yields higher platelet numbers, occurs independently of the key regulator of megakaryopoiesis thrombopoietin, and may occur during situations of acute platelet need. PMID:25963815

  20. Fan-structure waves in shear ruptures

    NASA Astrophysics Data System (ADS)

    Tarasov, Boris

    2016-04-01

    This presentation introduces a recently identified shear rupture mechanism providing a paradoxical feature of hard rocks - the possibility of shear rupture propagation through the highly confined intact rock mass at shear stress levels significantly less than frictional strength. According to the fan-mechanism the shear rupture propagation is associated with consecutive creation of small slabs in the fracture tip which, due to rotation caused by shear displacement of the fracture interfaces, form a fan-structure representing the fracture head. The fan-head combines such unique features as: extremely low shear resistance (below the frictional strength), self-sustaining stress intensification in the rupture tip (providing easy formation of new slabs), and self-unbalancing conditions in the fan-head (making the failure process inevitably spontaneous and violent). An important feature of the fan-mechanism is the fact that for the initial formation of the fan-structure an enhanced local shear stress is required, however, after completion of the fan-structure it can propagate as a dynamic wave through intact rock mass at shear stresses below the frictional strength. Paradoxically low shear strength of pristine rocks provided by the fan-mechanism determines the correspondingly low transient strength of the lithosphere, which favours generation of new earthquake faults in the intact rock mass adjoining pre-existing faults in preference to frictional stick-slip instability along these faults. The new approach reveals an alternative role of pre-existing faults in earthquake activity: they represent local stress concentrates in pristine rock adjoining the fault where special conditions for the fan-mechanism nucleation are created, while further dynamic propagation of the new fault (earthquake) occurs at low field stresses even below the frictional strength.

  1. Functional orthosis post pectoralis muscle rupture.

    PubMed

    Moore, Jodi

    2015-01-01

    This author described her success at fabricating a chest compression orthosis for a patient who underwent repair of a pectoralis major muscle rupture. The repair occurred nine months prior to orthotic fabrication, but the patient continued to experience weakness and pain which limited motion. The design of the orthotic allowed him increased mobility and functional use. - Victoria Priganc, PhD, OTR, CHT, CLT, Practice Forum Editor. PMID:26043967

  2. An unusual presentation of bronchial rupture.

    PubMed

    Goktalay, Tugba; Yaldiz, Sadik; Ozgen Alpaydin, Aylin; Goktan, Cihan; Celik, Pinar

    2011-06-01

    Persistent hydropneumothorax was diagnosed in a 62-year-old female with a history of blunt trauma, although she was treated with chest tube and closed underwater seal drainage. Computed tomography and fiberoptic bronchoscopy findings were consistent with "fallen lung" syndrome. Fiberoptic bronchoscopy also found a cavitary lesion at the right tracheobronchial angle. Forceps biopsy of the cavitary lesion indicated bronchogenic carcinoma. Our final diagnosis was tracheobronchial complete rupture and fallen lung syndrome secondary to malignancy. PMID:21333086

  3. Wrapped Wire Detects Rupture Of Pressure Vessel

    NASA Technical Reports Server (NTRS)

    Hunt, James B.

    1990-01-01

    Simple, inexpensive technique helps protect against damage caused by continuing operation of equipment after rupture or burnout of pressure vessel. Wire wrapped over area on outside of vessel where breakthrough most likely. If wall breaks or burns, so does wire. Current passing through wire ceases, triggering cutoff mechanism stopping flow in vessel to prevent further damage. Applied in other situations in which pipes or vessels fail due to overpressure, overheating, or corrosion.

  4. Rupture directivity of moderate earthquakes in northern California

    USGS Publications Warehouse

    Seekins, Linda C.; Boatwright, John

    2010-01-01

    We invert peak ground velocity and acceleration (PGV and PGA) to estimate rupture direction and rupture velocity for 47 moderate earthquakes (3.5≥M≥5.4) in northern California. We correct sets of PGAs and PGVs recorded at stations less than 55–125 km, depending on source depth, for site amplification and source–receiver distance, then fit the residual peak motions to the unilateral directivity function of Ben-Menahem (1961). We independently invert PGA and PGV. The rupture direction can be determined using as few as seven peak motions if the station distribution is sufficient. The rupture velocity is unstable, however, if there are no takeoff angles within 30° of the rupture direction. Rupture velocities are generally subsonic (0.5β–0.9β); for stability, we limit the rupture velocity at v=0.92β, the Rayleigh wave speed. For 73 of 94 inversions, the rupture direction clearly identifies one of the nodal planes as the fault plane. The 35 strike-slip earthquakes have rupture directions that range from nearly horizontal (6 events) to directly updip (5 events); the other 24 rupture partly along strike and partly updip. Two strike-slip earthquakes rupture updip in one inversion and downdip in the other. All but 1 of the 11 thrust earthquakes rupture predominantly updip. We compare the rupture directions for 10 M≥4.0 earthquakes to the relative location of the mainshock and the first two weeks of aftershocks. Spatial distributions of 8 of 10 aftershock sequences agree well with the rupture directivity calculated for the mainshock.

  5. Cyclooxygenase-2 Inhibition Attenuates Abdominal Aortic Aneurysm Progression in Hyperlipidemic Mice

    PubMed Central

    Ghoshal, Sarbani; Loftin, Charles D.

    2012-01-01

    Abdominal aortic aneurysms (AAAs) are a chronic inflammatory disease that increase the risk of life-threatening aortic rupture. In humans, AAAs have been characterized by increased expression of cyclooxygenase-2 and the inactivation of COX-2 prior to disease initiation reduces AAA incidence in a mouse model of the disease. The current study examined the effectiveness of selective cyclooxygenase-2 (COX-2) inhibition on reducing AAA progression when administered after the initiation of AAA formation. AAAs were induced in hyperlipidemic apolipoprotein E-deficient mice by chronic angiotensin II (AngII) infusion and the effect of treatment with the COX-2 inhibitor celecoxib was examined when initiated at different stages of the disease. Celecoxib treatment that was started 1 week after initiating AngII infusion reduced AAA incidence by 61% and significantly decreased AAA severity. Mice treated with celecoxib also showed significantly reduced aortic rupture and mortality. Treatment with celecoxib that was started at a late stage of AAA development also significantly reduced AAA incidence and severity. Celecoxib treatment significantly increased smooth muscle alpha-actin expression in the abdominal aorta and did not reduce expression of markers of macrophage-dependent inflammation. These findings indicate that COX-2 inhibitor treatment initiated after formation of AngII-induced AAAs effectively reduces progression of the disease in hyperlipidemic mice. PMID:23209546

  6. Single Event Gate Rupture in EMCCD technology

    NASA Astrophysics Data System (ADS)

    Evagora, A. M.; Murray, N. J.; Holland, A. D.; Burt, D.

    2012-12-01

    The high electric fields (typically 3 MV/cm2 interpoly field) utilised in Electron Multiplying Charged Coupled Devices (EMCCDs) reveal a potential vulnerability from Single Event Phenomena (SEP), in particular Single Event Gate Rupture (SEGR). SEGR is where a conduction path between two conductive areas of the CCD is produced, causing device failure. If EMCCDs are to be used for space applications the susceptibility to these events needs to be explored. A positive result from such an investigation can increase the technology readiness level of the device moving it another step closer to being used in space. Testing undertaken at the CYClotron of LOuvain la NEuve (CYCLONE), using the Heavy Ion Facility (HIF), conclusively showed EMCCD technology to have resilience to heavy ions that surpassed initial expectations. The simulations undertaken prior to experiment suggested gate rupture would occur at 20-40 MeV cm2/mg, however Linear Energy Transfers (LETs) greater than 100 MeV cm2/mg proved to not cause a rupture event. Within the radiation belts heavy ions with an LET greater than 60 MeV cm2/mg are not very common when compared to the fluxes used at the HIF. Possible reasons for this result are discussed in this work, leading to a conclusion that EMCCD technology is a secure choice for space flight.

  7. Carotid artery rupture and cervicofacial actinomycosis.

    PubMed

    Kummer, Anne; Lhermitte, Benoît; Ödman, Micaela; Grabherr, Silke; Mangin, Patrice; Palmiere, Cristian

    2012-11-01

    Cervicofacial actinomycosis is an uncommon, progressive infection caused by bacilli of the Actinomyces genus. Actinomyces are common commensal saprophytes in the oral cavity which may have medical importance as facultative pathogens. Subsequent to local injuries to the oral mucosa, they may penetrate the deep tissues and be responsible for suppurative or granulomatous infections. We herein report a case of a 65-year-old man who underwent surgery followed by chemotherapy and radiotherapy for a tonsillar carcinoma. An ulcerous lesion in the base of the tongue developed and spread to the carotid artery wall. The man died of a massive hemorrhage due to left carotid artery rupture. Postmortem computed tomography angiography performed prior to autopsy allowed the precise localization of the source of bleeding to be detected. Postmortem biochemical investigations confirmed the presence of inflammation associated with local bacterial infection. Histological investigations revealed the rupture of the left carotid artery surrounded by numerous colonies of Actinomyces. Acute and chronic inflammation with tissue necrosis as well as post-actinic, fibrotic changes were also found in the tissues surrounding the ruptured artery wall. PMID:22819527

  8. Rupture models with dynamically determined breakdown displacement

    USGS Publications Warehouse

    Andrews, D.J.

    2004-01-01

    The critical breakdown displacement, Dc, in which friction drops to its sliding value, can be made dependent on event size by specifying friction to be a function of variables other than slip. Two such friction laws are examined here. The first is designed to achieve accuracy and smoothness in discrete numerical calculations. Consistent resolution throughout an evolving rupture is achieved by specifying friction as a function of elapsed time after peak stress is reached. Such a time-weakening model produces Dc and fracture energy proportional to the square root of distance rupture has propagated in the case of uniform stress drop. The second friction law is more physically motivated. Energy loss in a damage zone outside the slip zone has the effect of increasing Dc and limiting peak slip velocity (Andrews, 1976). This article demonstrates a converse effect, that artificially limiting slip velocity on a fault in an elastic medium has a toughening effect, increasing fracture energy and Dc proportionally to rupture propagation distance in the case of uniform stress drop. Both the time-weakening and the velocity-toughening models can be used in calculations with heterogeneous stress drop.

  9. Rupture of plasma membrane under tension.

    PubMed

    Tan, Samuel Chun Wei; Yang, Tianyi; Gong, Yingxue; Liao, Kin

    2011-04-29

    We present a study on the rupture behavior of single NIH 3T3 mouse fibroblasts under tension using micropipette aspiration. Membrane rupture was characterized by breaking and formation of an enclosed membrane linked to a tether at the cell apex. Three different rupture modes, namely: single break, initial multiple breaks, and continuous multiple breaks, were observed under similar loading condition. The measured mean tensile strengths of plasma membrane were 3.83 ± 1.94 and 3.98 ± 1.54mN/m for control cells and cells labeled with TubulinTracker, respectively. The tensile strength data was described by Weibull distribution. For the control cells, the Weibull modulus and characteristic strength were 1.86 and 4.40 mN/m, respectively; for cells labeled with TubulinTracker, the Weibull modulus and characteristic strength were 2.68 and 4.48 mN/m, respectively. Based on the experimental data, the estimated average transmembrane proteins-lipid cleavage strength was 2.64 ± 0.64 mN/m. From the random sampling of volume ratio of transmembrane proteins in cell membrane, we concluded that the Weibull characteristic of plasma membrane strength was likely to be originated from the variation in transmembrane proteins-lipid interactions. PMID:21288526

  10. [Traumatic rupture of the thoracic aorta].

    PubMed

    Glock, Y; Roux, D; Soula, P; Cerene, A; Fournial, G

    1996-01-01

    This is a retrospective analysis of 50 postraumatic aortic rupture (1968-1996, 39 males, mean age: 34.5). Group A is composed of 35 patients with an acute aortic rupture and a prompt diagnosis. Group B includes 13 patients with a chronic rupture. All patients from group A had a severe politraumatism with abdominal, cranial, extremities or hip fractures. Mediastinal thickening with or without hemothorax indicated an angiography or a transesophageal echocardiography lately. In group A, 36 patients have been operated on urgently (12-24 hours); cardiopulmonary bypass was performed on 20 patients; an aorto-aortical bypass was done in 27 cases and a direct suture in the remaining 9. In group B, cardiopulmonary bypass was performed on 9 patients; a aorto-aortical bypass was done in 11 cases and a direct suture in 2. Overall hospital mortality was 16%; 19% in group A and 7.6% in group B. Ischemic paraplejia appeared in 5 patients (10%), all from group A. No false aneurysm developed after 4.5 years of follow-up (3-135 months) in the 38 survivors. The usefulness of transesophageal echocardiography, the importance of medular protection and the utility of several interventionist radiologic techniques are discussed. PMID:9053930

  11. Intersonic and Supersonic ruptures in a model of dynamic rupture in a layered medium

    NASA Astrophysics Data System (ADS)

    Ma, X.; Elbanna, A. E.

    2014-12-01

    The velocity structure in the lithosphere is quite complex and is rarely homogeneous. Wave reflection, transmission, and diffraction from the boundaries of the different layers and inclusions are expected to lead to a rich dynamic response and significantly affect rupture propagation on embedded faults. Here, we report our work on modeling dynamic rupture in an elastic domain with an embedded soft (stiff) layer as a first step towards modeling rupture propagation in realistic velocity structures. We use the Finite Element method (Pylith) to simulate rupture on a 2D in-plane fault embedded in an elastic full space. The simulated domain is 30 km wide and 100km long. Absorbing boundary conditions are used around the edges of the domain to simulate an infinite extension in all directions. The fault operates under linear slip-weakening friction law. We initiate the rupture by artificially overstressing a localized region near the left edge of the fault. We consider embedded soft/stiff layers with 20% to 60% reduction/increase of wave velocity respectively. The embedded layers are placed at different distances from the fault surface. We observed that the existence of a soft layer significantly shortens the transition length to supershear propagation through the Burridge-Andrews mechanism. The higher the material contrast, the shorter the transition length to supershear propagation becomes. We also observe that supershear rupture could be generated at pretress values that are lower than what is theoretically predicted for a homogeneous medium. We find that the distance from the lower boundary of the soft layer to the fault surface has a stronger influence on the supershear transition length as opposed to the thickness of the soft layer. In the existence of an embedded stiffer layer we found that rupture could propagate faster than the fault zone P-wave speed. In this case, the propagating rupture generate two Mach cones; one is associated with the shear wave, and the

  12. Spontaneous subarachnoid hemorrhage due to ruptured cavernous internal carotid artery aneurysm after medical prolactinoma treatment.

    PubMed

    Khalsa, Siri Sahib; Hollon, Todd C; Shastri, Ravi; Trobe, Jonathan D; Gemmete, Joseph J; Pandey, Aditya S

    2016-01-01

    Aneurysms of the cavernous segment of the internal carotid artery (ICA) are believed to have a low risk of subarachnoid haemorrhage (SAH), given the confines of the dural rings and the anterior clinoid process. The risk may be greater when the bony and dural protection has been eroded. We report a case of spontaneous SAH from rupture of a cavernous ICA aneurysm in a patient whose large prolactinoma had markedly decreased in size as the result of cabergoline treatment. After passing a balloon test occlusion, the patient underwent successful endovascular vessel deconstruction. This case suggests that an eroding skull base lesion may distort normal anterior cranial base anatomy and allow communication between the cavernous ICA and subarachnoid space. The potential for SAH due to cavernous ICA aneurysm rupture should be recognised in patients with previous pituitary or other skull base lesions adjacent to the cavernous sinus. PMID:27277584

  13. Targeting the AAA ATPase p97 as an approach to treat cancer through disruption of protein homeostasis

    PubMed Central

    Anderson, Daniel J.; Le Moigne, Ronan; Djakovic, Stevan; Kumar, Brajesh; Rice, Julie; Wong, Steve; Wang, Jinhai; Yao, Bing; Valle, Eduardo; von Soly, Szerenke Kiss; Madriaga, Antonett; Soriano, Ferdie; Menon, Mary-Kamala; Wu, Zhi Yong; Kampmann, Martin; Chen, Yuwen; Weissman, Jonathan S.; Aftab, Blake T.; Yakes, F. Michael; Shawver, Laura; Zhou, Han-Jie; Wustrow, David; Rolfe, Mark

    2016-01-01

    Summary p97 is a AAA-ATPase with multiple cellular functions, one of which is critical regulation of protein homeostasis pathways. We describe the characterization of CB-5083, a potent, selective and orally bioavailable inhibitor of p97. Treatment of tumor cells with CB-5083 leads to accumulation of poly-ubiquitinated proteins, retention of endoplasmic reticulum associated degradation (ERAD) substrates and generation of irresolvable proteotoxic stress leading to activation of the apoptotic arm of the unfolded protein response (UPR). In xenograft models, CB-5083 causes modulation of key p97-related pathways, induces apoptosis and has antitumor activity in a broad range of both hematological and solid tumor models. Molecular determinants of CB-5083 activity include expression of genes in the ERAD pathway providing a potential strategy for patient selection. PMID:26555175

  14. Structural Characterization of a Newly Identified Component of α-Carboxysomes: The AAA+ Domain Protein CsoCbbQ.

    PubMed

    Sutter, Markus; Roberts, Evan W; Gonzalez, Raul C; Bates, Cassandra; Dawoud, Salma; Landry, Kimberly; Cannon, Gordon C; Heinhorst, Sabine; Kerfeld, Cheryl A

    2015-01-01

    Carboxysomes are bacterial microcompartments that enhance carbon fixation by concentrating ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and its substrate CO2 within a proteinaceous shell. They are found in all cyanobacteria, some purple photoautotrophs and many chemoautotrophic bacteria. Carboxysomes consist of a protein shell that encapsulates several hundred molecules of RuBisCO, and contain carbonic anhydrase and other accessory proteins. Genes coding for carboxysome shell components and the encapsulated proteins are typically found together in an operon. The α-carboxysome operon is embedded in a cluster of additional, conserved genes that are presumably related to its function. In many chemoautotrophs, products of the expanded carboxysome locus include CbbO and CbbQ, a member of the AAA+ domain superfamily. We bioinformatically identified subtypes of CbbQ proteins and show that their genes frequently co-occur with both Form IA and Form II RuBisCO. The α-carboxysome-associated ortholog, CsoCbbQ, from Halothiobacillus neapolitanus forms a hexamer in solution and hydrolyzes ATP. The crystal structure shows that CsoCbbQ is a hexamer of the typical AAA+ domain; the additional C-terminal domain, diagnostic of the CbbQ subfamily, structurally fills the inter-monomer gaps, resulting in a distinctly hexagonal shape. We show that CsoCbbQ interacts with CsoCbbO and is a component of the carboxysome shell, the first example of ATPase activity associated with a bacterial microcompartment. PMID:26538283

  15. Structural Characterization of a Newly Identified Component of α-Carboxysomes: The AAA+ Domain Protein CsoCbbQ

    SciTech Connect

    Sutter, Markus; Roberts, Evan W.; Gonzalez, Raul C.; Bates, Cassandra; Dawoud, Salma; Landry, Kimberly; Cannon, Gordon C.; Heinhorst, Sabine; Kerfeld, Cheryl A.

    2015-11-05

    Carboxysomes are bacterial microcompartments that enhance carbon fixation by concentrating ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and its substrate CO2 within a proteinaceous shell. They are found in all cyanobacteria, some purple photoautotrophs and many chemoautotrophic bacteria. Carboxysomes consist of a protein shell that encapsulates several hundred molecules of RuBisCO, and contain carbonic anhydrase and other accessory proteins. Genes coding for carboxysome shell components and the encapsulated proteins are typically found together in an operon. The α-carboxysome operon is embedded in a cluster of additional, conserved genes that are presumably related to its function. In many chemoautotrophs, products of the expanded carboxysome locus include CbbO and CbbQ, a member of the AAA+ domain superfamily. We bioinformatically identified subtypes of CbbQ proteins and show that their genes frequently co-occur with both Form IA and Form II RuBisCO. The α-carboxysome-associated ortholog, CsoCbbQ, from Halothiobacillus neapolitanus forms a hexamer in solution and hydrolyzes ATP. The crystal structure shows that CsoCbbQ is a hexamer of the typical AAA+ domain; the additional C-terminal domain, diagnostic of the CbbQ subfamily, structurally fills the inter-monomer gaps, resulting in a distinctly hexagonal shape. Finally, we show that CsoCbbQ interacts with CsoCbbO and is a component of the carboxysome shell, the first example of ATPase activity associated with a bacterial microcompartment.

  16. Structural Characterization of a Newly Identified Component of α-Carboxysomes: The AAA+ Domain Protein CsoCbbQ

    DOE PAGESBeta

    Sutter, Markus; Roberts, Evan W.; Gonzalez, Raul C.; Bates, Cassandra; Dawoud, Salma; Landry, Kimberly; Cannon, Gordon C.; Heinhorst, Sabine; Kerfeld, Cheryl A.

    2015-11-05

    Carboxysomes are bacterial microcompartments that enhance carbon fixation by concentrating ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and its substrate CO2 within a proteinaceous shell. They are found in all cyanobacteria, some purple photoautotrophs and many chemoautotrophic bacteria. Carboxysomes consist of a protein shell that encapsulates several hundred molecules of RuBisCO, and contain carbonic anhydrase and other accessory proteins. Genes coding for carboxysome shell components and the encapsulated proteins are typically found together in an operon. The α-carboxysome operon is embedded in a cluster of additional, conserved genes that are presumably related to its function. In many chemoautotrophs, products of the expanded carboxysome locusmore » include CbbO and CbbQ, a member of the AAA+ domain superfamily. We bioinformatically identified subtypes of CbbQ proteins and show that their genes frequently co-occur with both Form IA and Form II RuBisCO. The α-carboxysome-associated ortholog, CsoCbbQ, from Halothiobacillus neapolitanus forms a hexamer in solution and hydrolyzes ATP. The crystal structure shows that CsoCbbQ is a hexamer of the typical AAA+ domain; the additional C-terminal domain, diagnostic of the CbbQ subfamily, structurally fills the inter-monomer gaps, resulting in a distinctly hexagonal shape. Finally, we show that CsoCbbQ interacts with CsoCbbO and is a component of the carboxysome shell, the first example of ATPase activity associated with a bacterial microcompartment.« less

  17. Three semidominant barley mutants with single amino acid substitutions in the smallest magnesium chelatase subunit form defective AAA+ hexamers

    PubMed Central

    Hansson, A.; Willows, R. D.; Roberts, T. H.; Hansson, M.

    2002-01-01

    Many enzymes of the bacteriochlorophyll and chlorophyll biosynthesis pathways have been conserved throughout evolution, but the molecular mechanisms of the key steps remain unclear. The magnesium chelatase reaction is one of these steps, and it requires the proteins BchI, BchD, and BchH to catalyze the insertion of Mg2+ into protoporphyrin IX upon ATP hydrolysis. Structural analyses have shown that BchI forms hexamers and belongs to the ATPases associated with various cellular activities (AAA+) family of proteins. AAA+ proteins are Mg2+-dependent ATPases that normally form oligomeric ring structures in the presence of ATP. By using ATPase-deficient BchI subunits, we demonstrate that binding of ATP is sufficient to form BchI oligomers. Further, ATPase-deficient BchI proteins can form mixed oligomers with WT BchI. The formation of BchI oligomers is not sufficient for magnesium chelatase activity when combined with BchD and BchH. Combining WT BchI with ATPase-deficient BchI in an assay disrupts the chelatase reaction, but the presence of deficient BchI does not inhibit ATPase activity of the WT BchI. Thus, the ATPase of every WT segment of the hexamer is autonomous, but all segments of the hexamer must be capable of ATP hydrolysis for magnesium chelatase activity. We suggest that ATP hydrolysis of each BchI within the hexamer causes a conformational change of the hexamer as a whole. However, hexamers containing ATPase-deficient BchI are unable to perform this ATP-dependent conformational change, and the magnesium chelatase reaction is stalled in an early stage. PMID:12357035

  18. Structural Characterization of a Newly Identified Component of α-Carboxysomes: The AAA+ Domain Protein CsoCbbQ

    PubMed Central

    Sutter, Markus; Roberts, Evan W.; Gonzalez, Raul C.; Bates, Cassandra; Dawoud, Salma; Landry, Kimberly; Cannon, Gordon C.; Heinhorst, Sabine; Kerfeld, Cheryl A.

    2015-01-01

    Carboxysomes are bacterial microcompartments that enhance carbon fixation by concentrating ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and its substrate CO2 within a proteinaceous shell. They are found in all cyanobacteria, some purple photoautotrophs and many chemoautotrophic bacteria. Carboxysomes consist of a protein shell that encapsulates several hundred molecules of RuBisCO, and contain carbonic anhydrase and other accessory proteins. Genes coding for carboxysome shell components and the encapsulated proteins are typically found together in an operon. The α-carboxysome operon is embedded in a cluster of additional, conserved genes that are presumably related to its function. In many chemoautotrophs, products of the expanded carboxysome locus include CbbO and CbbQ, a member of the AAA+ domain superfamily. We bioinformatically identified subtypes of CbbQ proteins and show that their genes frequently co-occur with both Form IA and Form II RuBisCO. The α-carboxysome-associated ortholog, CsoCbbQ, from Halothiobacillus neapolitanus forms a hexamer in solution and hydrolyzes ATP. The crystal structure shows that CsoCbbQ is a hexamer of the typical AAA+ domain; the additional C-terminal domain, diagnostic of the CbbQ subfamily, structurally fills the inter-monomer gaps, resulting in a distinctly hexagonal shape. We show that CsoCbbQ interacts with CsoCbbO and is a component of the carboxysome shell, the first example of ATPase activity associated with a bacterial microcompartment. PMID:26538283

  19. Coupling geodynamic earthquake cycles and dynamic ruptures

    NASA Astrophysics Data System (ADS)

    van Zelst, Iris; van Dinther, Ylona; Gabriel, Alice-Agnes; Heuret, Arnauld

    2016-04-01

    Studying the seismicity in a subduction zone and its effects on tsunamis requires diverse modelling methods that span spatial and temporal scales. Hundreds of years are necessary to build the stresses and strengths on a fault, while consequent earthquake rupture propagation is determined by both these initial fault conditions and the feedback of seismic waves over periods of seconds up to minutes. This dynamic rupture displaces the sea floor, thereby causing tsunamis. The aim of the ASCETE (Advanced Simulations of Coupled Earthquake and Tsunami Events) project is to study all these aspects and their interactions. Here, we present preliminary results of the first aspects in this modelling chain: the coupling of a seismo-thermo-mechanical (STM) code to the dynamic rupture model SeisSol. STM models of earthquake cycles have the advantage of solving multiple earthquake events in a self-consistent manner concerning stress, strength and geometry. However, the drawback of these models is that they often lack in spatial or temporal resolution and do not include wave propagation. In contrast, dynamic rupture models solve for frictional failure coupled to seismic wave propagation. We use the software package SeisSol (www.seissol.org) based on an ADER-DG discretization allowing high-order accuracy in space and time as well as flexible tetrahedral meshing. However, such simulations require assumptions on the initial fault stresses and strengths and its geometry, which are hard to constrain due to the lack of near-field observations and the complexity of coseismic conditions. By adapting the geometry as well as the stress and strength properties of the self-consistently developing non-finite fault zones from the geodynamic models as initial conditions for the dynamic rupture models, the advantages of both methods are exploited and modelling results may be compared. Our results show that a dynamic rupture can be triggered spontaneously and that the propagating rupture is

  20. [Quadriceps tendon insufficiency and rupture : Treatment options in total knee arthroplasty].

    PubMed

    Thiele, K; von Roth, P; Pfitzner, T; Preininger, B; Perka, C

    2016-05-01

    Quadriceps tendon injuries and insufficiencies in total knee arthroplasty are rare, but are followed by a devastating complication that left untreated leads to a complete loss of function of the knee. This review article summarizes the functional anatomy, risk factors, and the prevalence and diagnosis of quadriceps tendon injuries, in addition to the possible management options for partial and complete ruptures. The treatment options are adapted according to the extent of the loss of function (partial, complete) and the duration of the injury (acute vs chronic). Furthermore, the choice of treatment should take into account the quality and availability of primary tissue, the patient's general health, along with their likely functional requirements. Conservative treatment is often justified in partial ruptures with good results. Complete ruptures require surgical intervention and multiple operative techniques are described. Treatment options for acute ruptures include direct primary repair with autogenous or synthetic tissue augmentation. In the case of chronic insufficiency and a lack of soft-tissue surroundings, reconstruction with the aid of a muscle flap or allograft tissue can be considered. All surgical intervention techniques used so far have been fraught with complications and rarely lead to satisfactory results. A new surgical approach to the reconstruction and augmentation of the extensor mechanism consists of the use of a synthetic mesh. The technique is described here in detail. PMID:27125235

  1. Treatment of a Ruptured Vertebrobasilar Fusiform Aneurysm Using Pipeline Embolization Device

    PubMed Central

    Tan, Lee A.; Lopes, Demetrius K.

    2013-01-01

    Treatment options of ruptured vertebrobasilar fusiform aneurysms (VFA) are limited and often carry significant mortality and morbidity. We report the use of Pipeline Embolization Device (PED) to successfully treat a patient with a ruptured vertebrobasilar fusiform aneurysm (VFA) who presented with subarachnoid hemorrhage (SAH). A 73 year-old man with a history of cardiac stent placement seven days earlier presented with Hunt-Hess II SAH. He was taking aspirin and clopidogrel. Computed tomography angiogram revealed a large vertebrobasilar fusiform aneurysm. Microsurgical treatment options are technically challenging and carry high risk. He underwent endovascular treatment of the ruptured VFA using overlapping PEDs. Five PEDs were placed in a telescoping fashion to reconstruct the affected portions of the left vertebral and basilar arteries. An additional 2-mm blister aneurysm in the right vertebral artery was also discovered during the conventional cerebral angiography and was treated with one additional PED. The patient remained neurologically intact after the procedure. He was continued on aspirin and clopidogrel. Follow-up magnetic resonance imaging at three months demonstrated patency of the stents without any evidence of ischemic change. Follow-up conventional cerebral angiogram at six months demonstrated thrombosis of the VFA and reconstruction of the vertebrobasilar system. The patient remained clinically well. An endovascular approach using PEDs can be a safe and effective treatment option for ruptured VFA in selected cases. PMID:23593603

  2. Vitamins C and E: missing links in preventing preterm premature rupture of membranes?

    PubMed

    Woods, J R; Plessinger, M A; Miller, R K

    2001-07-01

    We propose that generation of reactive oxygen species may be a potentially reversible pathophysiologic pathway leading to preterm premature rupture of the membranes. Reactive oxygen species generated by the body's response to diverse insults such as infection, cigarette smoking, bleeding, or cocaine use can activate collagenolytic enzymes and impair fetal membrane integrity. Vitamin E, a lipid-soluble antioxidant, inhibits membrane-damaging effects of reactive oxygen species-induced lipid peroxidation. Vitamin C, a water-soluble antioxidant in plasma, stimulates and protects collagen synthesis while recycling vitamin E. Prior evidence shows that (1) damage by reactive oxygen species can impair fetal membrane integrity, (2) reduced midgestation levels of vitamin C are associated with preterm premature rupture of membranes, and (3) these vitamins can be safely and effectively absorbed and delivered to gestational tissues. Current prenatal vitamin preparations contain vitamins C and E in concentrations that are less than 1/3 and 1/10, respectively; these levels have been suggested for effective antioxidant protection. We hypothesize that increased dietary consumption or supplementation of vitamins C and E during pregnancy may reduce physiologically the risks of that portion of preterm premature rupture of membranes that is mediated by excessive or undamped peroxidation of fetal membranes. This hypothesis, if confirmed, should stimulate initiation of therapeutic trials to test the efficacy of enhanced supplementation with vitamins C and E during pregnancy to prevent preterm premature rupture of membranes. PMID:11483896

  3. Protrusion of hepatocellular carcinoma is a predictor of early recurrence in hepatectomy patients after spontaneous rupture

    PubMed Central

    Han, Seung Rim; Choi, Gyu-Seong; Park, Jae Berm; Kwon, Choon Hyuck David; Kim, Sung Joo; Joh, Jae-Won

    2016-01-01

    Purpose The factors related to early-onset tumor recurrence in patients with spontaneously ruptured hepatocellular carcinoma (HCC) after hepatectomy remain unclear. The aims of the present study were to compare characteristics between early and late recurrence groups in spontaneously ruptured HCC patients who received curative hepatectomy and to identify risk factors for mortality. Methods We selected 19 patients who had been diagnosed with spontaneously ruptured HCC and who were treated with curative liver resection between 1998 and 2013. The 19 patients were divided into 2 groups: the early recurrence group of patients who experienced tumor recurrence within 12 months after hepatectomy, and the late recurrence group of patients who experienced recurrence after 12 months or who did not experience recurrence. Results The median tumor size was 7.4 cm, and there were no cases of postoperative mortality. Patient survival rates at 1, 3, and 5 years were 78.9%, 58.6%, and 58.6%, respectively. The incidence of tumor protrusion in the early recurrence group was higher than that in the late recurrence group (100% vs. 30%, respectively, P = 0.003). There were no statistically significant differences in other factors between the 2 groups. Multivariate analysis showed that greater than 30% protrusion of the tumor was a predictor of patient survival. Conclusion The results from the present study suggests that spontaneously ruptured HCC patients with protrusion should be frequently monitored after hepatectomy in order to achieve early detection of tumor recurrence and improve survival. PMID:27433460

  4. Exposure to Ambient Air Pollution and Premature Rupture of Membranes.

    PubMed

    Wallace, Maeve E; Grantz, Katherine L; Liu, Danping; Zhu, Yeyi; Kim, Sung Soo; Mendola, Pauline

    2016-06-15

    Premature rupture of membranes (PROM) is a major factor that predisposes women to preterm delivery. Results from previous studies have suggested that there are associations between exposure to air pollution and preterm birth, but evidence of a relationship with PROM is sparse. Modified Community Multiscale Air Quality models were used to estimate mean exposures to particulate matter less than 10 µm or less than 2.5 µm in aerodynamic diameter, nitrogen oxides, carbon monoxide, sulfur dioxide, and ozone among 223,375 singleton deliveries in the Air Quality and Reproductive Health Study (2002-2008). We used log-linear models with generalized estimating equations to estimate adjusted relative risks and 95% confidence intervals for PROM per each interquartile-range increase in pollutants across the whole pregnancy, on the day of delivery, and 5 hours before delivery. Whole-pregnancy exposures to carbon monoxide and sulfur dioxide were associated with an increased risk of PROM (for carbon monoxide, relative risk (RR) = 1.09, 95% confidence interval (CI): 1.04, 1.14; for sulfur dioxide, RR = 1.15, 95% CI: 1.06, 1.25) but not preterm PROM. Ozone exposure increased the risk of PROM on the day of delivery (RR = 1.06, 95% CI: 1.02, 1.09) and 1 day prior (RR = 1.04, 95% CI: 1.01, 1.07). In the 5 hours preceding delivery, there were 3%-7% increases in risk associated with exposure to ozone and particulate matter less than 2.5 µm in aerodynamic diameter and inverse associations with exposure to carbon monoxide and nitrogen oxides. Acute and long-term air pollutant exposures merit further study in relation to PROM. PMID:27188941

  5. Missed Iatrogenic Bladder Rupture Following Normal Vaginal Delivery

    PubMed Central

    Baheti, Vidyasagar H; Patwardhan, Sujata K

    2015-01-01

    Bladder rupture following caesarian section is well documented complications. Intraperitoneal bladder rupture following normal vaginal delivery is very rare. Hereby, we present a case report of intraperitoneal bladder rupture presented late following normal vaginal delivery. We report a case of spontaneous intraperitoneal urinary bladder rupture following uneventful outlet forceps delivery in a 22-year-old primi gravid woman with gestational diabetes mellitus and fetal macrosomia who presented with large urinary ascites, anuria and renal failure. Emergent exploratory laparotomy with repair of the intraperitoneal bladder rupture helped to prevent its potential complications. Postpartum patients who undergo episiotomy or perineal repair may land up in unnoticed urinary retention which may rarely terminate in spontaneous urinary bladder rupture. Awareness of its manifestations amongst emergency physician would help to initiate appropriate timely management. PMID:26557563

  6. Missed Iatrogenic Bladder Rupture Following Normal Vaginal Delivery.

    PubMed

    Baheti, Vidyasagar H; Wagaskar, Vinayak G; Patwardhan, Sujata K

    2015-10-01

    Bladder rupture following caesarian section is well documented complications. Intraperitoneal bladder rupture following normal vaginal delivery is very rare. Hereby, we present a case report of intraperitoneal bladder rupture presented late following normal vaginal delivery. We report a case of spontaneous intraperitoneal urinary bladder rupture following uneventful outlet forceps delivery in a 22-year-old primi gravid woman with gestational diabetes mellitus and fetal macrosomia who presented with large urinary ascites, anuria and renal failure. Emergent exploratory laparotomy with repair of the intraperitoneal bladder rupture helped to prevent its potential complications. Postpartum patients who undergo episiotomy or perineal repair may land up in unnoticed urinary retention which may rarely terminate in spontaneous urinary bladder rupture. Awareness of its manifestations amongst emergency physician would help to initiate appropriate timely management. PMID:26557563

  7. [SURGICAL TREATMENT OF PATIENTS WITH URETERAL RUPTURES].

    PubMed

    Komjakov, B K; Guliev, B G

    2015-01-01

    The aim of the study was to analyze the causes of ureteral ruptures and the types surgical procedures used for their management. Over the period from 2006 to 2014, 7 patients with ureteral ruptures underwent surgical treatment in the Mechnikov N-WSMU clinic. All of them were males aged 50 to 71 years. In all cases, the ureter was injured during ureteroscopy and contact lithotripsy. In two patients the right ureter was cut off at the border of the upper and middle third, in four--at 3-4 cm below pyeloureteral segment, one patient diagnosed with a complete separation of the ureter from the kidney pelvis. Patients, who have suffered a detachment of the ureter in other hospitals, previously underwent surgical exploration of the retroperitoneal space, drainage of the kidney by pyelonephrostomy (5) and ureterocutaneostomy (1). In a case of a patient with an injury that occurred in our clinic, laparoscopic nephrectomy with autologous renal transplantation was carried out. Five patients with extended ureter defects underwent ileo-ureteroplasty. The patient with left ureterocutaneostomy underwent nephrovesical bypass. Patency of the upper urinary tract and kidney function were restored in all patients, all of them were relieved from external drains. The duration of the intestinal plastic averaged 160 minutes, laparoscopic nephrectomy with autologous transplantation--210 min and nephrovesical bypass--110 min. Blood transfusion was required only in autologous graft patient. The ureteral rupture is a serious complication of ureteral endourological procedures in upper urinary tract. It requires such complicated reconstructive operations as autologous transplantation of the kidney or intestinal ureteroplasty. PMID:26390553

  8. Isolated unilateral rupture of the alar ligament.

    PubMed

    Wong, Sui-To; Ernest, Kimberly; Fan, Grace; Zovickian, John; Pang, Dachling

    2014-05-01

    Only 6 cases of isolated unilateral rupture of the alar ligament have been previously reported. The authors report a new case and review the literature, morbid anatomy, and pathogenesis of this rare injury. The patient in their case, a 9-year-old girl, fell head first from a height of 5 feet off the ground. She presented with neck pain, a leftward head tilt, and severe limitation of right rotation, extension, and right lateral flexion of the neck. Plain radiographs and CT revealed no fracture but a shift of the dens toward the right lateral mass of C-1. Magnetic resonance imaging of the cervical spine showed signal hyperintensity within the left dens-atlas space on both T1- and T2-weighted sequences and interruption of the expected dark signal representing the left alar ligament, suggestive of its rupture. After 12 weeks of immobilization in a Guilford brace, MRI showed lessened dens deviation, and the patient attained full and painless neck motion. Including the patient in this case, the 7 patients with this injury were between 5 and 21 years old, sustained the injury in traffic accidents or falls, presented with marked neck pain, and were treated with external immobilization. All patients had good clinical outcome. The mechanism of injury is hyperflexion with rotation. Isolated unilateral alar ligament rupture is a diagnosis made by excluding associated fracture, dislocation, or disruption of other major ligamentous structures in the craniovertebral junction. CT and MRI are essential in establishing the diagnosis. External immobilization is adequate treatment. PMID:24679079

  9. Dynamic stress changes during earthquake rupture

    USGS Publications Warehouse

    Day, S.M.; Yu, G.; Wald, D.J.

    1998-01-01

    We assess two competing dynamic interpretations that have been proposed for the short slip durations characteristic of kinematic earthquake models derived by inversion of earthquake waveform and geodetic data. The first interpretation would require a fault constitutive relationship in which rapid dynamic restrengthening of the fault surface occurs after passage of the rupture front, a hypothesized mechanical behavior that has been referred to as "self-healing." The second interpretation would require sufficient spatial heterogeneity of stress drop to permit rapid equilibration of elastic stresses with the residual dynamic friction level, a condition we refer to as "geometrical constraint." These interpretations imply contrasting predictions for the time dependence of the fault-plane shear stresses. We compare these predictions with dynamic shear stress changes for the 1992 Landers (M 7.3), 1994 Northridge (M 6.7), and 1995 Kobe (M 6.9) earthquakes. Stress changes are computed from kinematic slip models of these earthquakes, using a finite-difference method. For each event, static stress drop is highly variable spatially, with high stress-drop patches embedded in a background of low, and largely negative, stress drop. The time histories of stress change show predominantly monotonic stress change after passage of the rupture front, settling to a residual level, without significant evidence for dynamic restrengthening. The stress change at the rupture front is usually gradual rather than abrupt, probably reflecting the limited resolution inherent in the underlying kinematic inversions. On the basis of this analysis, as well as recent similar results obtained independently for the Kobe and Morgan Hill earthquakes, we conclude that, at the present time, the self-healing hypothesis is unnecessary to explain earthquake kinematics.

  10. Kinetics of hole nucleation in biomembrane rupture

    NASA Astrophysics Data System (ADS)

    Evans, Evan; Smith, Benjamin A.

    2011-09-01

    The core component of a biological membrane is a fluid-lipid bilayer held together by interfacial-hydrophobic and van der Waals interactions, which are balanced for the most part by acyl chain entropy confinement. If biomembranes are subjected to persistent tensions, an unstable (nanoscale) hole will emerge at some time to cause rupture. Because of the large energy required to create a hole, thermal activation appears to be requisite for initiating a hole and the activation energy is expected to depend significantly on mechanical tension. Although models exist for the kinetic process of hole nucleation in tense membranes, studies of membrane survival have failed to cover the ranges of tension and lifetime needed to critically examine nucleation theory. Hence, rupturing giant (~20 μm) membrane vesicles ultra-slowly to ultra-quickly with slow to fast ramps of tension, we demonstrate a method to directly quantify kinetic rates at which unstable holes form in fluid membranes, at the same time providing a range of kinetic rates from <0.01 to >100 s-1. Measuring lifetimes of many hundreds of vesicles, each tensed by precision control of micropipette suction, we have determined the rates of failure for vesicles made from several synthetic phospholipids plus 1:1 mixtures of phospho- and sphingo-lipids with cholesterol, all of which represent prominent constituents of eukaryotic cell membranes. Plotted on a logarithmic scale, the failure rates for vesicles are found to rise dramatically with an increase in tension. Converting the experimental profiles of kinetic rates into changes of activation energy versus tension, we show that the results closely match expressions for thermal activation derived from a combination of meso-scale theory and molecular-scale simulations of hole formation. Moreover, we demonstrate a generic approach to transform analytical fits of activation energies obtained from rupture experiments into energy landscapes characterizing the process of hole

  11. Vascular changes in the ruptured Achilles tendon and paratenon.

    PubMed

    Kvist, M; Józsa, L; Järvinen, M

    1992-01-01

    Thirty patients with ruptures of the Achilles tendon were studied. There were 21 men and 9 women with an average age of 36 years. Specimens from the tendon and paratenon in 24 were examined histologically. Tissue samples of 20 were studied by electron microscopy. Marked degenerative, obliterative and/or inflammatory vascular changes were found in all the ruptured tendons and their paratenon. Our findings indicate that poor vascularity play a role in the aetiology of rupture of the Achilles tendon. PMID:1473893

  12. Cohesive Zone Length of Gabbro at Supershear Rupture Velocity

    NASA Astrophysics Data System (ADS)

    Fukuyama, E.; Xu, S.; Mizoguchi, K.; Yamashita, F.

    2014-12-01

    We investigated the shear strain field ahead of a supershear rupture. The strain data was obtained during large-scale biaxial friction experiments conducted at NIED in March 2013. We conducted friction experiments using a pair of meter-scale gabbro rock specimens whose simulated fault area was 1.5m x 0.1m. We applied 2.6MPa normal stress and loading velocity of 0.1mm/s. At the long side of the fault edge, which is parallel to the slip direction, 32 2-component semi-conductor strain gauges were installed at an interval of 50mm and 10mm off the fault. The data are conditioned by high frequency strain amplifiers (<0.5MHz) and continuously recorded at an interval of 1MHz with 16-bit resolution. Many stick slip events were observed and a unilateral rupture event was chosen in this analysis that propagated with supershear rupture velocity. One of the reasons for this selection was that the strain field ahead of the supershear rupture was not contaminated by elastic waves. Focusing on the rupture front, stress concentration was observed and sharp stress drop occurred immediately inside the rupture. We found that the stress concentration becomes mild as the rupture propagates and length of the stress concentration area becomes longer. This observation is quite interesting because in this experiment the rupture propagated at a constant speed close to root two times the shear wave velocity and thus a longer stress concentration region suggests more energy dissipation. We could speculate that such longer stress concentration area suggests longer plastic region ahead of the rupture (or longer cohesive distance). I.e. the cohesive zone length becomes longer as the rupture propagates to maintain constant rupture velocity propagation. We empirically obtained the relation Lc = 1.8x10^-5 L for 0.1ruptured length.

  13. A Rare Case of Adductor Longus Muscle Rupture

    PubMed Central

    van de Kimmenade, R. J. L. L.; van Bergen, C. J. A.; van Deurzen, P. J. E.; Verhagen, R. A. W.

    2015-01-01

    An adductor longus muscle rupture is a rare injury. This case report describes a 32-year-old patient with an adductor longus rupture. The trauma mechanism was a hyperabduction movement during a soccer game. Nonoperative treatment was initiated. After a follow-up of 4 years, the patient was without pain but a small swelling was still visible. This report describes the anatomy, pathophysiology, and evidence-based treatment of adductor longus rupture. PMID:25918663

  14. Rupture of non-communicating rudimentary uterine horn pregnancy.

    PubMed

    Dhar, Hansa

    2008-01-01

    Unicornuate uterus with rudimentary horn is a rare type of uterine malformation associated with obstetrical complications. Rupture of pregnant rudimentary horn is the usual presentation resulting in severe haemoperitoneum with increased maternal morbidity, and at times, mortality. A case of ruptured rudimentary horn pregnancy in a 24-year-old, second gravida, is reported. Exploratory laparotomy revealed a ruptured rudimentary horn pregnancy of 14 weeks gestation with haemoperitoneum. Excision of the rudimentary horn was done and an uneventful recovery followed. PMID:18452672

  15. Experimental observation of ruptures propagating on heterogeneous interfaces

    NASA Astrophysics Data System (ADS)

    Campillo, M.; Latour, S.; Voisin, C.; Catheline, S.; Renard, F.; Larose, E. F.

    2013-12-01

    We present experimental observations of a propagating rupture interacting with one or several mechanical heterogeneities. We developed a friction laboratory experiment where a soft elastic solid slides past a rigid flat plate. The system is coupled to an original medical imaging technique, ultrasound speckle interferometry, that allows observing the rupture dynamics along the interface as well as the emitted elastic shear wavefield into the solid body. We compare the dynamics of propagating rupture for an homogeneous flat interface and for three cases of heterogeneous sliding surfaces: 1) an interface with a single point-like barrier made of a small rock pebble, 2) an interface with a single linear barrier that joins the edges of the faults in a direction perpendicular to slip 3) an interface with multiple barriers disposed on half of its surface area, creating an heterogeneous zone. We obtain experimental observations of dynamic effects that have been predicted by numerical dynamic rupture simulations and provide experimental observations of the following phenomena: a barrier can stop or delay the rupture propagation; a linear single barrier can change the rupture velocity, increasing or decreasing it; we observe transition from subshear to supershear propagation due to the linear barrier; a large heterogeneous area slows down the rupture propagation. We observe a strong variability of the rupture dynamics occurring for identical frictional conditions, that we impute to memory effects caused by the heterogeneity of the stress field due to both the loading conditions and the remaining stress field due to previous rupture events. These experiments therefore confirm previously reported numerical simulations of ruptures along heterogeneous interfaces. When comparing with natural observations or earthquake ruptures, our data provide some phenomenological insights to explain the complexity of the rupture history inferred from the pattern of seismic radiations.

  16. A rare case of adductor longus muscle rupture.

    PubMed

    van de Kimmenade, R J L L; van Bergen, C J A; van Deurzen, P J E; Verhagen, R A W

    2015-01-01

    An adductor longus muscle rupture is a rare injury. This case report describes a 32-year-old patient with an adductor longus rupture. The trauma mechanism was a hyperabduction movement during a soccer game. Nonoperative treatment was initiated. After a follow-up of 4 years, the patient was without pain but a small swelling was still visible. This report describes the anatomy, pathophysiology, and evidence-based treatment of adductor longus rupture. PMID:25918663

  17. Anisotropy in rupture lines of paper sheets

    NASA Astrophysics Data System (ADS)

    Menezes-Sobrinho, I. L.; Couto, M. S.; Ribeiro, I. R. B.

    2005-06-01

    We have experimentally investigated the fracture process in paper samples submitted to a uniaxial force. Five types of paper sheets (newsprint, towel, sulfite, silk, and couche papers) were fractured along two orthogonal orientations. In order to characterize the rupture lines of the paper sheets we utilized the Hurst exponent. Our results indicate a dependence of the Hurst exponent on the orientation of the paper sheets for samples of newsprint and, probably, towel and silk papers. For the other types of paper the Hurst exponent does not depend on the direction of crack propagation.

  18. Complex earthquake rupture and local tsunamis

    USGS Publications Warehouse

    Geist, E.L.

    2002-01-01

    In contrast to far-field tsunami amplitudes that are fairly well predicted by the seismic moment of subduction zone earthquakes, there exists significant variation in the scaling of local tsunami amplitude with respect to seismic moment. From a global catalog of tsunami runup observations this variability is greatest for the most frequently occuring tsunamigenic subduction zone earthquakes in the magnitude range of 7 < Mw < 8.5. Variability in local tsunami runup scaling can be ascribed to tsunami source parameters that are independent of seismic moment: variations in the water depth in the source region, the combination of higher slip and lower shear modulus at shallow depth, and rupture complexity in the form of heterogeneous slip distribution patterns. The focus of this study is on the effect that rupture complexity has on the local tsunami wave field. A wide range of slip distribution patterns are generated using a stochastic, self-affine source model that is consistent with the falloff of far-field seismic displacement spectra at high frequencies. The synthetic slip distributions generated by the stochastic source model are discretized and the vertical displacement fields from point source elastic dislocation expressions are superimposed to compute the coseismic vertical displacement field. For shallow subduction zone earthquakes it is demonstrated that self-affine irregularities of the slip distribution result in significant variations in local tsunami amplitude. The effects of rupture complexity are less pronounced for earthquakes at greater depth or along faults with steep dip angles. For a test region along the Pacific coast of central Mexico, peak nearshore tsunami amplitude is calculated for a large number (N = 100) of synthetic slip distribution patterns, all with identical seismic moment (Mw = 8.1). Analysis of the results indicates that for earthquakes of a fixed location, geometry, and seismic moment, peak nearshore tsunami amplitude can vary by a

  19. Anisotropy in rupture lines of paper sheets.

    PubMed

    Menezes-Sobrinho, I L; Couto, M S; Ribeiro, I R B

    2005-06-01

    We have experimentally investigated the fracture process in paper samples submitted to a uniaxial force. Five types of paper sheets (newsprint, towel, sulfite, silk, and couche papers) were fractured along two orthogonal orientations. In order to characterize the rupture lines of the paper sheets we utilized the Hurst exponent. Our results indicate a dependence of the Hurst exponent on the orientation of the paper sheets for samples of newsprint and, probably, towel and silk papers. For the other types of paper the Hurst exponent does not depend on the direction of crack propagation. PMID:16089834

  20. Blunt traumatic rupture of the right ventricle, with intrapericardial rupture of the diaphragm: successful surgical repair.

    PubMed

    Le Treut, Y P; Herve, L; Cardon, J M; Boutboul, R; Bricot, R

    1981-07-01

    The authors report a case of chest injury causing rupture of the right ventricle and diaphragm, discovered during laparotomy for haemoperitoneum. This type of injury to the heart has rarely been cited in the literature since survival rates are low and the diagnosis often overlooked. PMID:7319634

  1. Closed proximal muscle rupture of the biceps brachii in wakeboarders.

    PubMed

    Pascual-Garrido, Cecilia; Swanson, Britta L; Bannar, Stephen M

    2012-06-01

    Closed proximal muscle rupture of the biceps brachii is a rare injury. In this report, two cases of closed proximal muscle rupture of the biceps brachii after wakeboard traumas are described. Both patients presented with a swollen arm, weakness during flexion, and a mass in the affected forearm. Magnetic resonance imaging showed displacement of the biceps brachii into the forearm. The rupture was successfully treated with muscle removal in one case and muscle repair in the other. In patients with a wakeboard trauma and similar presentations, closed proximal muscle rupture of the biceps brachii should be suspected. PMID:21877295

  2. Rupture of giant vertebrobasilar aneurysm following flow diversion: mechanical stretch as a potential mechanism for early aneurysm rupture.

    PubMed

    Fox, Benjamin; Humphries, William Edward; Doss, Vinodh T; Hoit, Daniel; Elijovich, Lucas; Arthur, Adam S

    2014-01-01

    A patient with a giant symptomatic vertebrobasilar aneurysm was treated by endoscopic third ventriculostomy for obstructive hydrocephalus followed by treatment of the aneurysm by flow diversion using a Pipeline Embolization Device. After an uneventful procedure and initial periprocedural period, the patient experienced an unexpected fatal subarachnoid hemorrhage 1 week later. Autopsy demonstrated extensive subarachnoid hemorrhage and aneurysm rupture (linear whole wall rupture). The patent Pipeline Embolization Device was in its intended location, as was the persistent coil occlusion of the distal left vertebral artery. The aneurysm appeared to rupture in a linear manner and contained a thick large expansile clot that seemed to disrupt or rupture the thin aneurysm wall directly opposite the basilar artery/Pipeline Embolization Device. We feel the pattern of aneurysm rupture in our patient supports the idea that the combination of flow diversion and the resulting growing intra-aneurysmal thrombus can create a mechanical force with the potential to cause aneurysm rupture. PMID:25355741

  3. Rupture of giant vertebrobasilar aneurysm following flow diversion: mechanical stretch as a potential mechanism for early aneurysm rupture.

    PubMed

    Fox, Benjamin; Humphries, William Edward; Doss, Vinodh T; Hoit, Daniel; Elijovich, Lucas; Arthur, Adam S

    2015-11-01

    A patient with a giant symptomatic vertebrobasilar aneurysm was treated by endoscopic third ventriculostomy for obstructive hydrocephalus followed by treatment of the aneurysm by flow diversion using a Pipeline Embolization Device. After an uneventful procedure and initial periprocedural period, the patient experienced an unexpected fatal subarachnoid hemorrhage 1 week later. Autopsy demonstrated extensive subarachnoid hemorrhage and aneurysm rupture (linear whole wall rupture). The patent Pipeline Embolization Device was in its intended location, as was the persistent coil occlusion of the distal left vertebral artery. The aneurysm appeared to rupture in a linear manner and contained a thick large expansile clot that seemed to disrupt or rupture the thin aneurysm wall directly opposite the basilar artery/Pipeline Embolization Device. We feel the pattern of aneurysm rupture in our patient supports the idea that the combination of flow diversion and the resulting growing intra-aneurysmal thrombus can create a mechanical force with the potential to cause aneurysm rupture. PMID:25361560

  4. Percutaneous, Minimally Invasive Repair of Traumatic and Simultaneous Rupture of Both Achilles Tendons: A Case Report.

    PubMed

    Zietek, Pawel; Karaczun, Maciej; Kruk, Bartosz; Szczypior, Karina

    2016-01-01

    Achilles injury is a common musculoskeletal disorder. Bilateral rupture of the Achilles tendon, however, is much less common and usually occurs spontaneously. Complete, traumatic, and bilateral ruptures are rare and typically require long periods of immobilization before the patient can return to full weightbearing. A 52-year-old male was hospitalized for bilateral traumatic rupture to both Achilles tendons. No risk factors for tendon rupture were found. Blood samples revealed no peripheral blood pathologic features. Both tendons were repaired with percutaneous, minimally invasive surgery using the Achillon(®) tendon suture system. Rehabilitation was begun 4 weeks later. An ankle-foot orthosis was prescribed to provide ankle support with an adjustable range of movement, and active plantar flexion was set at 0° to 30°. The patient remained non-weightbearing with the ankle-foot orthosis device and performed active range-of-motion exercises. At 8 weeks after surgery, we recommended that he begin walking with partial weightbearing using a foot-tibial orthosis with the range of motion set to 45° plantar flexion and 15° dorsiflexion. At 10 weeks postoperatively, he was encouraged to return to full weightbearing on both feet. Beginning rehabilitation as soon as possible after minimally invasive surgery, compared with 6 weeks of immobilization after surgery, provided a rapid resumption to full weightbearing. We emphasize the clinical importance of a safe, simple treatment program that can be followed for a patient with damage to the Achilles tendons. To our knowledge, ours is the first report of minimally invasive repair of bilateral simultaneous traumatic rupture of the Achilles tendon. PMID:26002678

  5. Characteristics of Ground Motions from Large-Scale Dynamic Rupture Simulations

    NASA Astrophysics Data System (ADS)

    Shi, Z.; Day, S. M.

    2012-12-01

    We investigate the characteristics of ground motions generated using an all-physics-based deterministic approach. The rupture events are simulated as dynamic ruptures along rough faults using large-scale three-dimensional models. The fault roughness assumed in our study follows self-similar fractal distribution with the roughness wavelength scales spanning three orders of magnitude from ~10^2 m to ~10^5 m. Frictional sliding on the fault is governed by a rate- and-state friction with strongly rate-weakening property and the inelastic yielding of the off-fault bulk material is subject to Drucker-Prager viscoplasticity. Our simulation results show that the fault roughness promotes the development of self-healing rupture pulses and causes loss of rupture coherence. The resulting rupture irregularity lead to ground motions of considerable complexity. Ground accelerations that show extensive high-frequency oscillations exhibit a rich variety of phases and near-flat power spectra between a few tenths of one Hz to slightly less than 10 Hz. The patterns of fault-parallel, fault-normal, vertical and geometric-mean PGAs all show considerable level of variability that appears to be quantitatively similar to that found in earthquake strong motion records. We also computed the orientation-independent RotD50 response spectra of the ground accelerations for representative periods from 0.1 to 3.0 seconds. Compared to the Ground Motion Prediction Equations for the Next Generation Attenuation project (Power et al., 2008), these RotD50 response spectra are highly consistent with those empirical estimates, within the epistemic uncertainty, giving credence to the usefulness of our approach. Our study will contribute to the better understanding of the theoretical aspects of ground motion and hopefully provide useful guidance for the future development of the seismic risk analysis in practice.

  6. [Right atrium rupture due to blunt trauma].

    PubMed

    Suzuki, Kazuhiro; Thuboi, H; Okada, H

    2008-03-01

    We report 2 cases of surgical treatment of blunt cardiac trauma. The postoperative course was uneventful in either case. Pericardial drainage in patients with cardiac rupture should be performed with preparation for thoracotomy. Case 1: A 34-year-old male, hit in the chest by a collapsing 700-kg steel rod, was transported to our hospital via ambulance. The patient was diagnosed as having a cardiac rupture by echocardiography and underwent emergency thoracotomy. The right atrium near the inferior vena cava (IVC) was damaged, though bleeding from the wound had already ceased. No suture hemostusis was needed. Case 2: A 63-year-old female was hit by a car and transported to our hospital due to blunt trauma to the chest. Low blood pressure and chest computed tomography demonstrated cardiac tamponade, and subxiphoid pericardial drainage was performed. Blood pressure was recovered, but persistent hemorrhage necessitated emergency thoracotomy, which revealed a laceration at the right atrium near IVC. The injury was sutured to achieve complete hemostasis. PMID:18323181

  7. The repetition of large-earthquake ruptures.

    PubMed Central

    Sieh, K

    1996-01-01

    This survey of well-documented repeated fault rupture confirms that some faults have exhibited a "characteristic" behavior during repeated large earthquakes--that is, the magnitude, distribution, and style of slip on the fault has repeated during two or more consecutive events. In two cases faults exhibit slip functions that vary little from earthquake to earthquake. In one other well-documented case, however, fault lengths contrast markedly for two consecutive ruptures, but the amount of offset at individual sites was similar. Adjacent individual patches, 10 km or more in length, failed singly during one event and in tandem during the other. More complex cases of repetition may also represent the failure of several distinct patches. The faults of the 1992 Landers earthquake provide an instructive example of such complexity. Together, these examples suggest that large earthquakes commonly result from the failure of one or more patches, each characterized by a slip function that is roughly invariant through consecutive earthquake cycles. The persistence of these slip-patches through two or more large earthquakes indicates that some quasi-invariant physical property controls the pattern and magnitude of slip. These data seem incompatible with theoretical models that produce slip distributions that are highly variable in consecutive large events. Images Fig. 3 Fig. 7 Fig. 9 PMID:11607662

  8. Probability of rupture of multiple fault segments

    USGS Publications Warehouse

    Andrews, D.J.; Schwerer, E.

    2000-01-01

    Fault segments identified from geologic and historic evidence have sometimes been adopted as features limiting the likely extends of earthquake ruptures. There is no doubt that individual segments can sometimes join together to produce larger earthquakes. This work is a trial of an objective method to determine the probability of multisegment ruptures. The frequency of occurrence of events on all conjectured combinations of adjacent segments in northern California is found by fitting to both geologic slip rates and to an assumed distribution of event sizes for the region as a whole. Uncertainty in the shape of the distribution near the maximum magnitude has a large effect on the solution. Frequencies of individual events cannot be determined, but it is possible to find a set of frequencies to fit a model closely. A robust conclusion for the San Francisco Bay region is that large multisegment events occur on the San Andreas and San Gregorio faults, but single-segment events predominate on the extended Hayward and Calaveras strands of segments.

  9. How is a stick slip rupture initiated?

    NASA Astrophysics Data System (ADS)

    Fukuyama, E.; Mizoguchi, K.; Yamashita, F.; Kawakata, H.; Takizawa, S.

    2013-12-01

    We investigated the initiation process of stick slip events that occurred during large scale rock friction experiments conducted on the large scale shaking table at NIED (Fukuyama et al., 2012, AGU Fall meeting). We used a pair of Indian gabbro rock samples stacked vertically and applied normal and shear forces. The sliding area between the samples is 1.5m in length and 0.1m in width. We conducted a sequence of experiments using the same rock sample, and before each experiment we removed gouge particles created during the previous experiment by a brush and a cleaner. Here, we show the experiments under constant slip velocity of 0.1mm/s with constant normal stress of 2.7MPa (LB04-003) or 6.7MPa (LB04-005); the final displacement reached 0.04m. We used 44 acoustic sensors (PZT, vertical mode, 0.5MHz resonance frequency), 32 2-comp strain gouges (SGs) for shear strain and 16 1-comp SGs for normal strain measurements, with 48 0.5MHz dynamic SG amplifiers. We also used a 2MN load cell for shear force measurement and three 0.4MN load cells for vertical forces. Data are recorded continuously at an interval of 10MHz for PZT and 1MHz for other sensors. Just after the shear force applied, many stick slip events (SEs) occurred at an interval of a few seconds. By looking carefully at the PZT and SG array data during an SE, we found that one SE consists of many micro stick slip events (MSEs), which can be grouped into two (the former and the latter). These two groups correspond to the acceleration and deceleration stage of the SE. In LB04-005 (6.7MPa normal stress), a clear nucleation phase can be detected that initiated at a narrow area, propagate slowly (~20m/s) and accelerated. Then, a seismic rupture started to propagate at a velocity of ~3km/s (subshear) or ~6.5km/s (supershear). Detailed features are shown in Mizoguchi et al. (this meeting). It should be noted that this seismic rupture initiated at a narrow area inside the nucleation zone and sometimes after a certain

  10. Children with ANSD fitted with hearing aids applying the AAA Pediatric Amplification Guideline: Current Practice and Outcomes

    PubMed Central

    Walker, Elizabeth A.; McCreery, Ryan W.; Spratford, Meredith; Roush, Patricia A.

    2015-01-01

    Background Up to 15% of children with permanent hearing loss have auditory neuropathy spectrum disorder (ANSD), which involves normal outer hair cell function and disordered afferent neural activity in the auditory nerve or brainstem. Given the varying presentations of ANSD in children, there is a need for more evidence-based research on appropriate clinical interventions for this population. Purpose This study compared the speech production, speech perception, and language outcomes of children with auditory neuropathy spectrum disorder (ANSD) who are hard of hearing and children with similar degrees of mild to moderately-severe sensorineural hearing loss (SNHL), all of whom were fitted with bilateral hearing aids based on the American Academy of Audiology (AAA) pediatric amplification guidelines. Research design Speech perception and communication outcomes data were gathered in a prospective accelerated longitudinal design, with entry into the study between six months and seven years of age. Three sites were involved in participant recruitment: Boys Town National Research Hospital, the University of North Carolina at Chapel Hill, and the University of Iowa. Study sample: The sample consisted of 12 children with ANSD and 22 children with SNHL. The groups were matched based on better-ear pure-tone average, better-ear aided speech intelligibility index, gender, maternal education level, and newborn hearing screening result (i.e., pass or refer). Data collection and analysis Children and their families participated in an initial baseline visit, followed by visits twice a year for children under age 2 years and once a year for children older than 2 years. Paired-sample t-tests were used to compare children with ANSD to children with SNHL. Results Paired t-tests indicated no significant differences between the ANSD and SNHL groups on language and articulation measures. Children with ANSD displayed functional speech perception skills in quiet. Although the number of

  11. Rupture of splenic artery aneurysm in primipara five days after cesarean section: case report and review of the literature.

    PubMed

    Barišić, Tatjana; Šutalo, Nikica; Letica, Ludvig; Kordić, Andrea Vladimira

    2015-11-01

    Splenic artery aneurysm (SAA) is a rare and usually asymptomatic vascular anomaly which carries the risk of rupture and fatal hemorrhage. It is more common in women and is usually associated with pregnancy. We present the case of rupture of SAA, 5 days after giving birth by cesarean section, which was diagnosed with Multi-Slice Computed Tomografy (MSCT) angiography and was successfully operated in the second emergency laparotomy, with the final good outcome for the mother. This case indicates that in case of sudden bleeding in the abdomen, with the development of hypovolemic shock, especially in the peripartum period, should be suspected rupture of SAA. The paper presents a critical review of this case, with a review of the literature. PMID:26373746

  12. [Hemoperitoneum caused by rupture of a benign tumor of the liver in women taking oral contraceptives. 2 cases].

    PubMed

    Nicodeme, J P; Levy, J B; Gendrel, T; Costet, H; Prestat, J; Reynes, M; James, J M

    1976-06-01

    2 cases of rupture of benign liver tumors in women who had received oral contraceptive (OC) treatment for over 7 years are reported. Although the number of cases of benign liver tumor is very small, it has been increasing in recent years. The role of OCs in determining them is still unproven, and the risk appears to be extremely low (between 1 in 500,000 and 1 in 1,000,000); however, it is possible that favor the growth of preexisting lesions or the occurrence of rupture with hemorrhages. It is concluded that the possibility of such cases must be considered by physicians, and that early detection and surgery are required in order to remove the tumor before its rupture and consequent hemorrhage. PMID:934872

  13. Successful management of a ruptured mycotic pseudoaneurysm following pancreas transplantation using bovine pericardial patch: a case report.

    PubMed

    Yiannoullou, P; van Dellen, D; Khambalia, H; Forgacs, B; Tavakoli, A; Murray, D; Augustine, T

    2014-01-01

    Arterial mycotic pseudoaneurysms are a rare complication of pancreas transplantation. Rupture results in catastrophic hemorrhage with a high risk of mortality. Definitive management is complicated by an extensive arterial defect within a contaminated surgical field. Synthetic vascular grafts often fail due to subsequent graft infection whereas primary repair often results in arterial stenosis. Arterial ligation may be required to prevent exsanguination. A 41-year-old man, type 1 diabetic with associated renal failure, underwent successful simultaneous pancreas and kidney transplantation. He presented, 9 months following transplantation, with life-threatening rectal bleeding secondary to a ruptured mycotic pseudoaneurysm. This was successfully managed with a bovine pericardial patch (BPP) repair of the arterial defect and enteric diversion following graft pancreatectomy. He remains well with no vascular insufficiency 18 months following the procedure. A ruptured mycotic pseudoaneurysm following transplantation carries a significant risk of mortality and represents a surgical challenge as conventional techniques using synthetic materials often fail due to the contaminated field. A BPP offers good handling characteristics, excellent hemostatic properties and a favorable profile of infection risk in comparison with synthetic grafts. This case highlights its use as a treatment for a post-transplantation ruptured mycotic pseudoaneurysm. PMID:25131098

  14. Risk Stratification of Patients with Peripheral Arterial Disease and Abdominal Aortic Aneurysm Using Aortic Augmentation Index

    PubMed Central

    Beckmann, Marianne; Husmann, Marc

    2015-01-01

    Background Central augmentation index (cAIx) is an indicator for vascular stiffness. Obstructive and aneurysmatic vascular disease can affect pulse wave propagation and reflection, causing changes in central aortic pressures. Aim To assess and compare cAIx in patients with peripheral arterial disease (PAD) and / or abdominal aortic aneurysm (AAA). Methods cAIx was assessed by radial applanation tonometry (Sphygmocor) in a total of 184 patients at a tertiary referral centre. Patients were grouped as having PAD only, AAA only, or both AAA and PAD. Differences in cAIx measurements between the three patient groups were tested by non-parametric tests and stepwise multivariate linear regression analysis to investigate associations with obstructive or aneurysmatic patterns of vascular disease. Results In the study sample of 184 patients, 130 had PAD only, 20 had AAA only, and 34 patients had both AAA and PAD. Mean cAIx (%) was 30.5 ± 8.2 across all patients. It was significantly higher in females (35.2 ± 6.1, n = 55) than males (28.4 ± 8.2, n = 129), and significantly higher in patients over 80 years of age (34.4 ± 6.9, n = 22) than in those under 80 years (30.0 ± 8.2, n = 162). Intergroup comparison revealed a significant difference in cAIx between the three patient groups (AAA: 27.3 ± 9.5; PAD: 31.4 ± 7.8; AAA & PAD: 28.8 ± 8.5). cAIx was significantly lower in patients with AAA, higher in patients with both AAA and PAD, and highest in patients with PAD only (beta = 0.21, p = 0.006). Conclusion Non-invasive assessment of arterial stiffness in high-risk patients indicates that cAIx differs according to the pattern of vascular disease. Measurements revealed significantly higher cAIx values for patients with obstructive peripheral arterial disease than for patients with aneurysmatic disease. PMID:26452151

  15. Cigarette Smoke and Inflammation: Role in Cerebral Aneurysm Formation and Rupture

    PubMed Central

    Chalouhi, Nohra; Ali, Muhammad S.; Starke, Robert M.; Jabbour, Pascal M.; Tjoumakaris, Stavropoula I.; Gonzalez, L. Fernando; Rosenwasser, Robert H.; Koch, Walter J.; Dumont, Aaron S.

    2012-01-01

    Smoking is an established risk factor for subarachnoid hemorrhage yet the underlying mechanisms are largely unknown. Recent data has implicated a role of inflammation in the development of cerebral aneurysms. Inflammation accompanying cigarette smoke exposure may thus be a critical pathway underlying the development, progression, and rupture of cerebral aneurysms. Various constituents of the inflammatory response appear to be involved including adhesion molecules, cytokines, reactive oxygen species, leukocytes, matrix metalloproteinases, and vascular smooth muscle cells. Characterization of the molecular basis of the inflammatory response accompanying cigarette smoke exposure will provide a rational approach for future targeted therapy. In this paper, we review the current body of knowledge implicating cigarette smoke-induced inflammation in cerebral aneurysm formation/rupture and attempt to highlight important avenues for future investigation. PMID:23316103

  16. Pregnancy with a ruptured renal artery aneurysm: management concerns and endovascular management.

    PubMed

    Yadav, Siddharth; Sharma, Sanjay; Singh, Prabhjot; Nayak, Brusabhanu

    2015-01-01

    Renal artery aneurysm (RAA) affects <0.01% of the general population. Rupture of RAA is a rare catastrophe that can complicate pregnancy and is associated with high maternal and fetal mortality. Presentation is usually acute with severe flank pain, with or without haematuria, and haemodynamic instability requiring exploration and nephrectomy. A 26-year-old pregnant woman had sudden onset of gross haematuria and on evaluation was found to have a left RAA with an intrapelvic rupture and thinned out renal parenchyma. In view of the high risk of surgery, she was managed with endovascular placement of an Amplatzer type II vascular plug. Immediate and complete occlusion of blood flow was achieved and nephrectomy was avoided. Follow-up Doppler ultrasound revealed a reduced 5 cm mass in the left renal fossa with no internal flow and plug in position. She is currently on follow-up with 3-6 monthly ultrasonography not requiring any intervention. PMID:26504094

  17. [Complete urethral rupture with symphysis injury and anterior pelvic ring fracture during spontaneous delivery].

    PubMed

    Klotz, T; Derakhshani, P; Vorreuther, R; Engelmann, U

    1998-01-01

    We report on a complete longitudinal rupture of the urethra in combination with a rupture of the pubic symphysis and pelvic fracture during spontaneous vaginal delivery. Only after stabilisation of the pelvic fracture by external skeletal fixation adaptation of the urethra was possible. Three weeks later after removing of the transurethral catheter a mild stress incontinence could be observed. In the follow up one year later the patient was completely continent. The cosmetic result was satisfactory. There was no cystocele. An unclear haematuria after delivery needs a meticulous urological examination. Early repair of urethral disruption minimize the risk of severe incontinence. Coordinated care between the trauma surgeon and urologist is required for successful treatment of this rare combined injury after birth. PMID:9540189

  18. [Therapeutic strategies for postinfarction left ventricular free wall rupture].

    PubMed

    Koyanagi, Toshiya; Shimokawa, T; Ida, T; Kasegawa, H; Tobaru, T; Sumiyoshi, T

    2005-04-01

    We treated 93 patients who developed left ventricular free wall rupture after acute myocardial infarction. Medical management including pericardial drainage was performed in 78 patients (84%), but 67 of them died. All 11 surviving patients showed an oozing type rupture. Surgical repair was performed in 15 patients (16%). As a result, 9 patients died and 6 survived. All but 1 of the patients who died presented with a blow-out rupture. Blow-out type rupture occurred in 3 and oozing type rupture in 3 of the surviving patients. One patient with blow-out type rupture underwent implantation of a left ventricular assist device following percutaneous cardiopulmonary support (PCPS), because of low output syndrome after the operation. The device was successfully removed 7 days after implantation. In all of the 3 patients with oozing type rupture, sutureless technique was successfully performed using fibrin-glue or fibrin-glue sheet fixation. After a mean follow-up period of 7 years after operation, 5 of 6 are still alive. To improve the clinical outcome of left ventricular free wall rupture, it is important for surgeons to closely liaise with physicians, to perform surgical repair as soon as possible, and to utilize a circulatory support system after operation. Therefore, we developed a new PCPS system compatible with emergency cardiac surgery and a new left ventricular assist system draining via the left ventricle. PMID:15828243

  19. An Epigastric Heteropagus Twin with Ruptured Giant Omphalocele

    PubMed Central

    Dar, Sajid Hameed; Iqbal, Javaid; Latif, Tariq; Iqbal, Asif

    2014-01-01

    We present a case of heteropagus twins attached to the epigastric region. The neonate also had ruptured giant omphalocoele with most of gut and liver lying outside the abdominal cavity. Patient had uneventful surgery for separation of twins and repair of ruptured omphalocoele. PMID:26023494

  20. Ruptured bicornuate uterus mimicking ectopic pregnancy: A case report.

    PubMed

    Singh, Nisha; Singh, Uma; Verma, Manju Lata

    2013-01-01

    Ruptured uterus presenting in first trimester of pregnancy is extremely uncommon and should raise the suspicion of uterine malformations. We report a case of a 24-year-old primigravida with 10 weeks of gestation presenting with acute abdomen and hemoperitoneum. Laparotomy revealed bicornuate uterus with ruptured rudimentary horn. The incidence, diagnosis and management of such cases is discussed. PMID:22691311

  1. Simultaneous bilateral quadriceps tendon rupture while playing basketball.

    PubMed

    Shah, M; Jooma, N

    2002-04-01

    Simultaneous bilateral quadriceps tendon rupture is an uncommon injury in healthy people and only a few cases have been reported in athletes. This is the first report of a patient with simultaneous bilateral quadriceps tendon rupture incurred while playing basketball. The injury was surgically repaired and the patient had a good functional outcome. PMID:11916903

  2. Late rupture of extensor pollicis longus after wrist arthroscopy.

    PubMed

    Fortems, Y; Mawhinney, I; Lawrence, T; Trial, I A; Stanley, J K

    1995-06-01

    The first cases of impending rupture of the extensor pollicis longus after wrist arthroscopy are reported and the etiology is compared with extensor pollicis longus ruptures after nondisplaced or minimally displaced Colles fractures. Both cases were treated with extensor indices proprius to extensor pollicis longus transfer with good clinical results. PMID:7632309

  3. The Resolution of Ruptures in the Therapeutic Alliance.

    ERIC Educational Resources Information Center

    Safran, Jeremy D.; Muran, J. Christopher

    1996-01-01

    A rupture in the therapeutic alliance is a deterioration in the quality of the relationship between patient and therapist; it is an interpersonal marker that indicates an opportunity for exploring and understanding the processes that maintain a maladaptive interpersonal schema. Outlines features of a research program on ruptures in the therapeutic…

  4. Diverse rupture processes in the 2015 Peru deep earthquake doublet

    PubMed Central

    Ye, Lingling; Lay, Thorne; Kanamori, Hiroo; Zhan, Zhongwen; Duputel, Zacharie

    2016-01-01

    Earthquakes in deeply subducted oceanic lithosphere can involve either brittle or dissipative ruptures. On 24 November 2015, two deep (606 and 622 km) magnitude 7.5 and 7.6 earthquakes occurred 316 s and 55 km apart. The first event (E1) was a brittle rupture with a sequence of comparable-size subevents extending unilaterally ~50 km southward with a rupture speed of ~4.5 km/s. This earthquake triggered several aftershocks to the north along with the other major event (E2), which had 40% larger seismic moment and the same duration (~20 s), but much smaller rupture area and lower rupture speed than E1, indicating a more dissipative rupture. A minor energy release ~12 s after E1 near the E2 hypocenter, possibly initiated by the S wave from E1, and a clear aftershock ~165 s after E1 also near the E2 hypocenter, suggest that E2 was likely dynamically triggered. Differences in deep earthquake rupture behavior are commonly attributed to variations in thermal state between subduction zones. However, the marked difference in rupture behavior of the nearby Peru doublet events suggests that local variations of stress state and material properties significantly contribute to diverse behavior of deep earthquakes. PMID:27386585

  5. Diverse rupture processes in the 2015 Peru deep earthquake doublet.

    PubMed

    Ye, Lingling; Lay, Thorne; Kanamori, Hiroo; Zhan, Zhongwen; Duputel, Zacharie

    2016-06-01

    Earthquakes in deeply subducted oceanic lithosphere can involve either brittle or dissipative ruptures. On 24 November 2015, two deep (606 and 622 km) magnitude 7.5 and 7.6 earthquakes occurred 316 s and 55 km apart. The first event (E1) was a brittle rupture with a sequence of comparable-size subevents extending unilaterally ~50 km southward with a rupture speed of ~4.5 km/s. This earthquake triggered several aftershocks to the north along with the other major event (E2), which had 40% larger seismic moment and the same duration (~20 s), but much smaller rupture area and lower rupture speed than E1, indicating a more dissipative rupture. A minor energy release ~12 s after E1 near the E2 hypocenter, possibly initiated by the S wave from E1, and a clear aftershock ~165 s after E1 also near the E2 hypocenter, suggest that E2 was likely dynamically triggered. Differences in deep earthquake rupture behavior are commonly attributed to variations in thermal state between subduction zones. However, the marked difference in rupture behavior of the nearby Peru doublet events suggests that local variations of stress state and material properties significantly contribute to diverse behavior of deep earthquakes. PMID:27386585

  6. Rupture of Right Hepatic Duct into Hydatid Cyst

    PubMed Central

    Laskou, Styliani; Papavramidis, Theodossis S.; Pliakos, Ioannis; Kotidis, Eustathios; Kesisoglou, Isaak; Papavramidis, Spiros T.

    2012-01-01

    Echinococcal disease can develop anywhere in the human body. The liver represents its most frequent location. Hepatic hydatid cysts may rupture into the biliary tract, thorax, peritoneum, viscera, digestive tract or skin. We report a rare case with rupture of the right hepatic duct into a hydatid cyst in a woman with known hydatid disease and choledocholithiasis. The increased intra-luminal pressure in the biliary tree caused the rupture into the adjacent hydatid cyst. The creation of the fistula between the right hepatic duct and the hydatid cyst decompressed the biliary tree, decreased the bilirubin levels and offered a temporary resolution of the obstructive jaundice. Rupture of a hydatid cyst into the biliary tree usually leads to biliary colic, cholangitis and jaundice. However, in case of obstructive jaundice due to choledocholithiasis, it is possible that the cyst may rupture by other way around while offering the patient a temporary relief from his symptoms. PMID:22876065

  7. Material contrast does not predict earthquake rupture propagation direction

    USGS Publications Warehouse

    Harris, R.A.; Day, S.M.

    2005-01-01

    Earthquakes often occur on faults that juxtapose different rocks. The result is rupture behavior that differs from that of an earthquake occurring on a fault in a homogeneous material. Previous 2D numerical simulations have studied simple cases of earthquake rupture propagation where there is a material contrast across a fault and have come to two different conclusions: 1) earthquake rupture propagation direction can be predicted from the material contrast, and 2) earthquake rupture propagation direction cannot be predicted from the material contrast. In this paper we provide observational evidence from 70 years of earthquakes at Parkfield, CA, and new 3D numerical simulations. Both the observations and the numerical simulations demonstrate that earthquake rupture propagation direction is unlikely to be predictable on the basis of a material contrast. Copyright 2005 by the American Geophysical Union.

  8. [Missed traumatic diaphragmatic rupture--a legal insurance problem].

    PubMed

    Fabian, W; Reimer, H

    1991-08-01

    Even nowadays traumatic ruptures of the diaphragm cause diagnostic difficulties. Especially diaphragmatic ruptures of the so-called "late-type" are accompanied by uncharacteristic abdominal or cardio-respiratory complaints. These complaints depend on the type and the volume of the prolapsed organs. By hearing the classic previous history and symptoms the expert has to consider the diagnosis. Beside the previous history, the clinical evidents, the thoracic as well as the abdominal survey radiography, further informations can be given by Gastrointestinal passage with Gastrographin, by Colon contrast fluid enema and by abdominal CT. If there are no general contraindications, diaphragmatic ruptures have to be treated by surgery. There after patients are usually without complaints. Insurance-law-problems are unnecessarily created by "not identifying" fresh diaphragmatic ruptures and by "not considering" the possibility of "late-type" ruptures. PMID:1949474

  9. Roles of the N domain of the AAA+ Lon protease in substrate recognition, allosteric regulation and chaperone activity.

    PubMed

    Wohlever, Matthew L; Baker, Tania A; Sauer, Robert T

    2014-01-01

    Degron binding regulates the activities of the AAA+ Lon protease in addition to targeting proteins for degradation. The sul20 degron from the cell-division inhibitor SulA is shown here to bind to the N domain of Escherichia coli Lon, and the recognition site is identified by cross-linking and scanning for mutations that prevent sul20-peptide binding. These N-domain mutations limit the rates of proteolysis of model sul20-tagged substrates and ATP hydrolysis by an allosteric mechanism. Lon inactivation of SulA in vivo requires binding to the N domain and robust ATP hydrolysis but does not require degradation or translocation into the proteolytic chamber. Lon-mediated relief of proteotoxic stress and protein aggregation in vivo can also occur without degradation but is not dependent on robust ATP hydrolysis. In combination, these results demonstrate that Lon can function as a protease or a chaperone and reveal that some of its ATP-dependent biological activities do not require translocation. PMID:24205897

  10. Disassembly of mitotic checkpoint complexes by the joint action of the AAA-ATPase TRIP13 and p31comet

    PubMed Central

    Eytan, Esther; Wang, Kexi; Miniowitz-Shemtov, Shirly; Sitry-Shevah, Danielle; Kaisari, Sharon; Yen, Tim J.; Liu, Song-Tao; Hershko, Avram

    2014-01-01

    The mitotic (or spindle assembly) checkpoint system delays anaphase until all chromosomes are correctly attached to the mitotic spindle. When the checkpoint is active, a Mitotic Checkpoint Complex (MCC) assembles and inhibits the ubiquitin ligase Anaphase-Promoting Complex/Cyclosome (APC/C). MCC is composed of the checkpoint proteins Mad2, BubR1, and Bub3 associated with the APC/C activator Cdc20. When the checkpoint signal is turned off, MCC is disassembled and the checkpoint is inactivated. The mechanisms of the disassembly of MCC are not sufficiently understood. We have previously observed that ATP hydrolysis is required for the action of the Mad2-binding protein p31comet to disassemble MCC. We now show that HeLa cell extracts contain a factor that promotes ATP- and p31comet-dependent disassembly of a Cdc20–Mad2 subcomplex and identify it as Thyroid Receptor Interacting Protein 13 (TRIP13), an AAA-ATPase known to interact with p31comet. The joint action of TRIP13 and p31comet also promotes the release of Mad2 from MCC, participates in the complete disassembly of MCC and abrogates checkpoint inhibition of APC/C. We propose that TRIP13 plays centrally important roles in the sequence of events leading to MCC disassembly and checkpoint inactivation. PMID:25092294

  11. Thyroid Hormone Receptor Interacting Protein 13 (TRIP13) AAA-ATPase Is a Novel Mitotic Checkpoint-silencing Protein*

    PubMed Central

    Wang, Kexi; Sturt-Gillespie, Brianne; Hittle, James C.; Macdonald, Dawn; Chan, Gordon K.; Yen, Tim J.; Liu, Song-Tao

    2014-01-01

    The mitotic checkpoint (or spindle assembly checkpoint) is a fail-safe mechanism to prevent chromosome missegregation by delaying anaphase onset in the presence of defective kinetochore-microtubule attachment. The target of the checkpoint is the E3 ubiquitin ligase anaphase-promoting complex/cyclosome. Once all chromosomes are properly attached and bioriented at the metaphase plate, the checkpoint needs to be silenced. Previously, we and others have reported that TRIP13 AAA-ATPase binds to the mitotic checkpoint-silencing protein p31comet. Here we show that endogenous TRIP13 localizes to kinetochores. TRIP13 knockdown delays metaphase-to-anaphase transition. The delay is caused by prolonged presence of the effector for the checkpoint, the mitotic checkpoint complex, and its association and inhibition of the anaphase-promoting complex/cyclosome. These results suggest that TRIP13 is a novel mitotic checkpoint-silencing protein. The ATPase activity of TRIP13 is essential for its checkpoint function, and interference with TRIP13 abolished p31comet-mediated mitotic checkpoint silencing. TRIP13 overexpression is a hallmark of cancer cells showing chromosomal instability, particularly in certain breast cancers with poor prognosis. We suggest that premature mitotic checkpoint silencing triggered by TRIP13 overexpression may promote cancer development. PMID:25012665

  12. The linker region plays a regulatory role in assembly and activity of the Vps4 AAA ATPase.

    PubMed

    Shestakova, Anna; Curtiss, Matt; Davies, Brian A; Katzmann, David J; Babst, Markus

    2013-09-13

    The AAA-type ATPase Vps4 functions with components of the ESCRT (endosomal sorting complex required for transport) machinery in membrane fission events that are essential for endosomal maturation, cytokinesis, and the formation of retroviruses. A key step in these events is the assembly of monomeric Vps4 into the active ATPase complex, which is aided in part by binding of Vps4 via its N-terminal MIT (microtubule interacting and trafficking) domain to its substrate ESCRT-III. We found that the 40-amino acid linker region between the MIT and the ATPase domain of Vps4 is not required for proper function but plays a role in regulating Vps4 assembly and ATPase activity. Deletion of the linker is expected to bring the MIT domains into close proximity to the central pore of the Vps4 complex. We propose that this localization of the MIT domain in linker-deleted Vps4 mimics a repositioning of the MIT domain normally caused by binding of Vps4 to ESCRT-III. This structure would allow the Vps4 complex to engage ESCRT-III subunits with both the pore and the MIT domain simultaneously, which might be essential for the ATP-driven disassembly of ESCRT-III. PMID:23913684

  13. Structural insights into the Escherichia coli lysine decarboxylases and molecular determinants of interaction with the AAA+ ATPase RavA

    PubMed Central

    Kandiah, Eaazhisai; Carriel, Diego; Perard, Julien; Malet, Hélène; Bacia, Maria; Liu, Kaiyin; Chan, Sze W. S.; Houry, Walid A.; Ollagnier de Choudens, Sandrine; Elsen, Sylvie; Gutsche, Irina

    2016-01-01

    The inducible lysine decarboxylase LdcI is an important enterobacterial acid stress response enzyme whereas LdcC is its close paralogue thought to play mainly a metabolic role. A unique macromolecular cage formed by two decamers of the Escherichia coli LdcI and five hexamers of the AAA+ ATPase RavA was shown to counteract acid stress under starvation. Previously, we proposed a pseudoatomic model of the LdcI-RavA cage based on its cryo-electron microscopy map and crystal structures of an inactive LdcI decamer and a RavA monomer. We now present cryo-electron microscopy 3D reconstructions of the E. coli LdcI and LdcC, and an improved map of the LdcI bound to the LARA domain of RavA, at pH optimal for their enzymatic activity. Comparison with each other and with available structures uncovers differences between LdcI and LdcC explaining why only the acid stress response enzyme is capable of binding RavA. We identify interdomain movements associated with the pH-dependent enzyme activation and with the RavA binding. Multiple sequence alignment coupled to a phylogenetic analysis reveals that certain enterobacteria exert evolutionary pressure on the lysine decarboxylase towards the cage-like assembly with RavA, implying that this complex may have an important function under particular stress conditions. PMID:27080013

  14. Regulation of the transcriptional activator NtrC1: structural studies of the regulatory and AAA+ ATPase domains

    PubMed Central

    Lee, Seok-Yong; De La Torre, Armando; Yan, Dalai; Kustu, Sydney; Nixon, B. Tracy; Wemmer, David E.

    2003-01-01

    Transcription by σ54 RNA polymerase depends on activators that contain ATPase domains of the AAA+ class. These activators, which are often response regulators of two-component signal transduction systems, remodel the polymerase so that it can form open complexes at promoters. Here, we report the first crystal structures of the ATPase domain of an activator, the NtrC1 protein from the extreme thermophile Aquifex aeolicus. This domain alone, which is active, crystallized as a ring-shaped heptamer. The protein carrying both the ATPase and adjacent receiver domains, which is inactive, crystallized as a dimer. In the inactive dimer, one residue needed for catalysis is far from the active site, and extensive contacts among the domains prevent oligomerization of the ATPase domain. Oligomerization, which completes the active site, depends on surfaces that are buried in the dimer, and hence, on a rearrangement of the receiver domains upon phosphorylation. A motif in the ATPase domain known to be critical for coupling energy to remodeling of polymerase forms a novel loop that projects from the middle of an α helix. The extended, structured loops from the subunits of the heptamer localize to a pore in the center of the ring and form a surface that could contact σ54. PMID:14561776

  15. Multiple sequence signals direct recognition and degradation of protein substrates by the AAA+ protease HslUV.

    PubMed

    Sundar, Shankar; McGinness, Kathleen E; Baker, Tania A; Sauer, Robert T

    2010-10-29

    Proteolysis is important for protein quality control and for the proper regulation of many intracellular processes in prokaryotes and eukaryotes. Discerning substrates from other cellular proteins is a key aspect of proteolytic function. The Escherichia coli HslUV protease is a member of a major family of ATP-dependent AAA+ degradation machines. HslU hexamers recognize and unfold native protein substrates and then translocate the polypeptide into the degradation chamber of the HslV peptidase. Although a wealth of structural information is available for this system, relatively little is known about mechanisms of substrate recognition. Here, we demonstrate that mutations in the unstructured N-terminal and C-terminal sequences of two model substrates alter HslUV recognition and degradation kinetics, including changes in V(max). By introducing N- or C-terminal sequences that serve as recognition sites for specific peptide-binding proteins, we show that blocking either terminus of the substrate interferes with HslUV degradation, with synergistic effects when both termini are obstructed. These results support a model in which one terminus of the substrate is tethered to the protease and the other terminus is engaged by the translocation/unfolding machinery in the HslU pore. Thus, degradation appears to consist of discrete steps, which involve the interaction of different terminal sequence signals in the substrate with different receptor sites in the HslUV protease. PMID:20837023

  16. Spatial distribution of nematodes in three banana ( Musa AAA) root parts considering two root thickness in three farm management systems

    NASA Astrophysics Data System (ADS)

    Araya, M.; De Waele, D.

    2004-10-01

    The spatial location of the banana ( Musa AAA) root parasitic nematodes within three root parts considering two root thickness was determined in three commercial farm management systems, which differ in weed and nematode management. Roots in each farm management system were classified in thick (>5 mm-d) and thin (1 ≤ 5 mm-d) roots. From each root type, the epidermis, the cortical parenchyma (CP) and the vascular cylinder (VC) were separated by fingernail, and nematodes were extracted by maceration of each root part. Independent of the farm management system, and for either root thickness, highest numbers of Radopholus similis per gram of root was found in the CP, followed by the epidermis and VC. The highest number of Helicotylencus spp., Pratylenchus spp. and the total nematode population per gram of root was found in the epidermis. Considering the number of nematodes per root part, the highest number of R. similis and total nematodes was located in the CP, while Helicotylenchus spp. and Pratylenchus spp. were concentrated in the epidermis. These patterns were approximately reproduced in the two root thickness and in the three farm management systems. This behavior suggests that injection of systemic nematicides into the plant pseudostem to replace the granular applications on surface soil might be promissory.

  17. Loss of the m-AAA protease subunit AFG₃L₂ causes mitochondrial transport defects and tau hyperphosphorylation.

    PubMed

    Kondadi, Arun Kumar; Wang, Shuaiyu; Montagner, Sara; Kladt, Nikolay; Korwitz, Anne; Martinelli, Paola; Herholz, David; Baker, Michael J; Schauss, Astrid C; Langer, Thomas; Rugarli, Elena I

    2014-05-01

    The m-AAA protease subunit AFG₃L₂ is involved in degradation and processing of substrates in the inner mitochondrial membrane. Mutations in AFG₃L₂ are associated with spinocerebellar ataxia SCA28 in humans and impair axonal development and neuronal survival in mice. The loss of AFG₃L₂ causes fragmentation of the mitochondrial network. However, the pathogenic mechanism of neurodegeneration in the absence of AFG₃L₂ is still unclear. Here, we show that depletion of AFG₃L₂ leads to a specific defect of anterograde transport of mitochondria in murine cortical neurons. We observe similar transport deficiencies upon loss of AFG₃L₂ in OMA1-deficient neurons, indicating that they are not caused by OMA1-mediated degradation of the dynamin-like GTPase OPA1 and inhibition of mitochondrial fusion. Treatment of neurons with antioxidants, such as N-acetylcysteine or vitamin E, or decreasing tau levels in axons restored mitochondrial transport in AFG₃L₂-depleted neurons. Consistently, tau hyperphosphorylation and activation of ERK kinases are detected in mouse neurons postnatally deleted for Afg3l2. We propose that reactive oxygen species signaling leads to cytoskeletal modifications that impair mitochondrial transport in neurons lacking AFG₃L₂. PMID:24681487

  18. In-situ monitoring of blood glucose level for dialysis machine by AAA-battery-size ATR Fourier spectroscopy

    NASA Astrophysics Data System (ADS)

    Hosono, Satsuki; Sato, Shun; Ishida, Akane; Suzuki, Yo; Inohara, Daichi; Nogo, Kosuke; Abeygunawardhana, Pradeep K.; Suzuki, Satoru; Nishiyama, Akira; Wada, Kenji; Ishimaru, Ichiro

    2015-07-01

    For blood glucose level measurement of dialysis machines, we proposed AAA-battery-size ATR (Attenuated total reflection) Fourier spectroscopy in middle infrared light region. The proposed one-shot Fourier spectroscopic imaging is a near-common path and spatial phase-shift interferometer with high time resolution. Because numerous number of spectral data that is 60 (= camera frame rare e.g. 60[Hz]) multiplied by pixel number could be obtained in 1[sec.], statistical-averaging improvement realize high-accurate spectral measurement. We evaluated the quantitative accuracy of our proposed method for measuring glucose concentration in near-infrared light region with liquid cells. We confirmed that absorbance at 1600[nm] had high correlations with glucose concentrations (correlation coefficient: 0.92). But to measure whole-blood, complex light phenomenon caused from red blood cells, that is scattering and multiple reflection or so, deteriorate spectral data. Thus, we also proposed the ultrasound-assisted spectroscopic imaging that traps particles at standing-wave node. Thus, if ATR prism is oscillated mechanically, anti-node area is generated around evanescent light field on prism surface. By elimination complex light phenomenon of red blood cells, glucose concentration in whole-blood will be quantify with high accuracy. In this report, we successfully trapped red blood cells in normal saline solution with ultrasonic standing wave (frequency: 2[MHz]).

  19. FY05 LDRD Fianl Report Investigation of AAA+ protein machines that participate in DNA replication, recombination, and in response to DNA damage LDRD Project Tracking Code: 04-LW-049

    SciTech Connect

    Sawicka, D; de Carvalho-Kavanagh, M S; Barsky, D; Venclovas, C

    2006-12-04

    The AAA+ proteins are remarkable macromolecules that are able to self-assemble into nanoscale machines. These protein machines play critical roles in many cellular processes, including the processes that manage a cell's genetic material, but the mechanism at the molecular level has remained elusive. We applied computational molecular modeling, combined with advanced sequence analysis and available biochemical and genetic data, to structurally characterize eukaryotic AAA+ proteins and the protein machines they form. With these models we have examined intermolecular interactions in three-dimensions (3D), including both interactions between the components of the AAA+ complexes and the interactions of these protein machines with their partners. These computational studies have provided new insights into the molecular structure and the mechanism of action for AAA+ protein machines, thereby facilitating a deeper understanding of processes involved in DNA metabolism.

  20. Management of distal biceps and triceps ruptures.

    PubMed

    Blackmore, Susan M; Jander, Ryan M; Culp, Randall W

    2006-01-01

    The management of distal biceps and triceps ruptures is reviewed. Epidemiology, clinical presentation, evaluation, surgical management, nonoperative management, and rehabilitation rationale and techniques are presented. Although various surgical repair techniques are used, none has been shown to produce superior clinical outcomes. The literature is lacking information to provide evidence-based decisions regarding rehabilitation strategies. Prospective studies comparing types and timing of repairs and timing and techniques for a postoperative program are needed. As that information is not yet available, the rehabilitation plan outlined in this article is based on timetables for healing tissue, strength of repair, prevention of complications, consideration of patient's medical history and injury history, and review of the literature. Familiarity with the different treatment options assists the surgeon and therapist tailor a therapy program that is optimal for each individual patient. PMID:16713863

  1. Can Severe Kyphoscoliosis Lead to Aorta Rupture?

    PubMed

    Kotopoulos, Constantinos; Karakasi, Maria Valeria; Kapetanakis, Stylianos; Pavlidis, Pavlos

    2016-09-01

    Neurofibromatosis type 1 is a polysystemic disease presenting with a multifaceted clinical picture. Clinical manifestations may present in the skin, as well as in the skeletal and cardiovascular system. The present study aims to describe and examine the case of a 46-year-old woman, who suffered from neurofibromatosis type 1 and died abruptly in the emergency room. The forensic examination attributed her death to traumatic rupture of the thoracic aorta resulting from an acute angulation that her vertebral column formed in the thoracic region (severe kyphosis). Outspread cutaneous neurofibromas, severe scoliosis, and osteoporosis (brittle bones) were observed during the autopsy. No atherosclerotic lesions were detected in the aortic lumen. To the authors' knowledge, no similar case has been reported throughout relevant literature. PMID:27323279

  2. Unresponsive primipara after rupture of membranes.

    PubMed

    Buechel, Johanna; Berset, Andreas; Lehmann, Michael A; Lapaire, Olav

    2015-01-01

    Amniotic fluid embolism, also called anaphylactoid syndrome of pregnancy, is a rare but severe problem in obstetrics. It occurs in 8/100,000 births and the maternal mortality is up to 90%. We report the case of a patient with amniotic fluid embolism who was transferred to our hospital. The initial presentation was an unresponsive patient after spontaneous rupture of the membranes. The massive hypotension and coagulopathy as well as fetal bradycardia of 60 bpm led, after stabilisation of the mother, to an emergency caesarean section. The neonate expired hours later, despite neonatological intensive care. During the operation, we had to deal with massive bleeding due to the coagulopathy. Through interdisciplinary teamwork including Bakri postpartum balloon insertion through the obstetrics team, uterine artery embolism by the interventional radiologists and transfusion of blood products, the maternal life was saved and the patient was discharged 9 days after admission. PMID:25883261

  3. [The different genotypes of MTHFR 1298A>C and PON1 -108C>T polymorphisms confer the increased risk of the abdominal aortic aneurysm in the smoking and nonsmoking persons].

    PubMed

    Strauss, Ewa; Waliszewski, Krzysztof; Pawlak, Andrzej L

    2005-01-01

    In abdominal aortic aneurysm (AAA) both the etiology and the pathogenesis are of the multifactorial character. The genetic component in the determination of this disease is proven by its familial occurrence. Smoking represents the best recognized risk factor of the AAA development. Increased concentrations of homocysteine (Hcy) in plasma are the common finding in these patients. It is assumed that the Hcy thiolactone, the most reactive metabolite of Hcy, may participate in the aortic wall destruction in AAA. The polymorphic variants of the methylenetetrahydrofolate reductase (MTHFR 677C>T and 1298A>C) influence tissue concentrations of the Hcy. Paraoxonase (PON1), the enzyme associated in plasma with the HDL fraction, as lactonase detoxicates the Hcy thiolactone. The promotor polymorphism of PON1 - 108C>T gene may determine the lower activity of this enzyme. In the case-control study of 106 patients with AAA and 97 healthy persons, the effects of selected genetic and nongenetic risk factors on development of AAA were assessed, considering the possibilities of interaction between them. It was found, that the arterial hypertension, cigarette smoking and the lower HDL fraction are independent risk factors of AAA. The arterial hypertension was a risk factor both in the smoking and the nonsmoking males, whereas the lower HDL fraction has been the risk factor only for the smoking men. By the multivariate analysis in the nonsmoking males the MTHFR 1298 AC and CC genotypes increased the risk of AAA development 4,8-fold in relation to the MTHFR 1298 AA nonsmoking males. In reference to the genotypes of the expected high impact on the metabolism of Hcy and of Hcy thiolactone, the genotypes of MTHFR 677TT and PON1 -108CT and TT were more frequent in smoking ones, but the difference was not significant. This observation fits with the assumption that the influence of smoking on the occurrence of AAA prevails over that of genetic variability. When the patients age was considered

  4. Bacterial DNA findings in ruptured and unruptured intracranial aneurysms.

    PubMed

    Pyysalo, Mikko J; Pyysalo, Liisa M; Pessi, Tanja; Karhunen, Pekka J; Lehtimäki, Terho; Oksala, Niku; Öhman, Juha E

    2016-05-01

    Objective Chronic inflammation has earlier been detected in ruptured intracranial aneurysms. A previous study detected both dental bacterial DNA and bacterial-driven inflammation in ruptured intracranial aneurysm walls. The aim of this study was to compare the presence of oral and pharyngeal bacterial DNA in ruptured and unruptured intracranial aneurysms. The hypothesis was that oral bacterial DNA findings would be more common and the amount of bacterial DNA would be higher in ruptured aneurysm walls than in unruptured aneurysm walls. Materials and methods A total of 70 ruptured (n = 42) and unruptured (n = 28) intracranial aneurysm specimens were obtained perioperatively in aneurysm clipping operations. Aneurysmal sac tissue was analysed using a real-time quantitative polymerase chain reaction to detect bacterial DNA from several oral species. Both histologically non-atherosclerotic healthy vessel wall obtained from cardiac by-pass operations (LITA) and arterial blood samples obtained from each aneurysm patient were used as control samples. Results Bacterial DNA was detected in 49/70 (70%) of the specimens. A total of 29/42 (69%) of the ruptured and 20/28 (71%) of the unruptured aneurysm samples contained bacterial DNA of oral origin. Both ruptured and unruptured aneurysm tissue samples contained significantly more bacterial DNA than the LITA control samples (p-values 0.003 and 0.001, respectively). There was no significant difference in the amount of bacterial DNA between the ruptured and unruptured samples. Conclusion Dental bacterial DNA can be found using a quantitative polymerase chain reaction in both ruptured and unruptured aneurysm walls, suggesting that bacterial DNA plays a role in the pathogenesis of cerebral aneurysms in general, rather than only in ruptured aneurysms. PMID:26777430

  5. Elements in nucleotide sensing and hydrolysis of the AAA+ disaggregation machine ClpB: a structure-based mechanistic dissection of a molecular motor

    SciTech Connect

    Zeymer, Cathleen Barends, Thomas R. M.; Werbeck, Nicolas D.; Schlichting, Ilme; Reinstein, Jochen

    2014-02-01

    High-resolution crystal structures together with mutational analysis and transient kinetics experiments were utilized to understand nucleotide sensing and the regulation of the ATPase cycle in an AAA+ molecular motor. ATPases of the AAA+ superfamily are large oligomeric molecular machines that remodel their substrates by converting the energy from ATP hydrolysis into mechanical force. This study focuses on the molecular chaperone ClpB, the bacterial homologue of Hsp104, which reactivates aggregated proteins under cellular stress conditions. Based on high-resolution crystal structures in different nucleotide states, mutational analysis and nucleotide-binding kinetics experiments, the ATPase cycle of the C-terminal nucleotide-binding domain (NBD2), one of the motor subunits of this AAA+ disaggregation machine, is dissected mechanistically. The results provide insights into nucleotide sensing, explaining how the conserved sensor 2 motif contributes to the discrimination between ADP and ATP binding. Furthermore, the role of a conserved active-site arginine (Arg621), which controls binding of the essential Mg{sup 2+} ion, is described. Finally, a hypothesis is presented as to how the ATPase activity is regulated by a conformational switch that involves the essential Walker A lysine. In the proposed model, an unusual side-chain conformation of this highly conserved residue stabilizes a catalytically inactive state, thereby avoiding unnecessary ATP hydrolysis.

  6. Structure of RavA MoxR AAA+ protein reveals the design principles of a molecular cage modulating the inducible lysine decarboxylase activity

    PubMed Central

    El Bakkouri, Majida; Gutsche, Irina; Kanjee, Usheer; Zhao, Boyu; Yu, Miao; Goret, Gael; Schoehn, Guy; Burmeister, Wim P.; Houry, Walid A.

    2010-01-01

    The MoxR family of AAA+ ATPases is widespread throughout bacteria and archaea but remains poorly characterized. We recently found that the Escherichia coli MoxR protein, RavA (Regulatory ATPase variant A), tightly interacts with the inducible lysine decarboxylase, LdcI/CadA, to form a unique cage-like structure. Here, we present the X-ray structure of RavA and show that the αβα and all-α subdomains in the RavA AAA+ module are arranged as in magnesium chelatases rather than as in classical AAA+ proteins. RavA structure also contains a discontinuous triple-helical domain as well as a β-barrel-like domain forming a unique fold, which we termed the LARA domain. The LARA domain was found to mediate the interaction between RavA and LdcI. The RavA structure provides insights into how five RavA hexamers interact with two LdcI decamers to form the RavA-LdcI cage-like structure. PMID:21148420

  7. Genomic organization and mapping of the mouse P26s4 ATPase gene: A member of the remarkably conserved AAA gene family

    SciTech Connect

    Hoyle, J.; Fisher, E.M.C.

    1996-01-01

    The eukaryotic genome contains a large family of ATPases in which each member has at least one highly conserved domain of approximately 200 amino acids with an ATP binding motif (the {open_quotes}AAA{close_quotes} domain). AAA ATPases play diverse roles in the cell and are of considerable interest to researchers investigating a number of different phenomena, including control of the cell cycle. We have characterized the mouse P26s4 AAA ATPase gene that encodes a subunit of the 26S protease, a multimeric complex that is responsible for the ubiquitin- and ATP-dependent degradation of specific proteins. The normal functioning of eukaryotic cells depends on this pathway to remove regulatory proteins such as cyclins or signal transduction molecules from the intracellular environment, with the appropriate timing to allow normal cell division and development. We have isolated mouse P26s4 cDNAs and mapped the P26s4 gene to chromosome 12. We have analyzed the intron-exon structure of the P26s4 genomic locus and have determined that the gene contains at least 10 introns, the first of which separates the start methionine from the rest of the coding sequence. 18 refs., 2 figs.

  8. Substrate delivery by the AAA+ ClpX and ClpC1 unfoldases activates the mycobacterial ClpP1P2 peptidase

    PubMed Central

    Schmitz, Karl R.; Sauer, Robert T.

    2014-01-01

    Summary Mycobacterial Clp-family proteases function via collaboration of the heteromeric ClpP1P2 peptidase with a AAA+ partner, ClpX or ClpC1. These enzymes are essential for M. tuberculosis viability and are validated antibacterial drug targets, but the requirements for assembly and regulation of functional proteolytic complexes are poorly understood. Here, we report the reconstitution of protein degradation by mycobacterial Clp proteases in vitro and describe novel features of these enzymes that distinguish them from orthologs in other bacteria. Both ClpX and ClpC1 catalyze ATP-dependent unfolding and degradation of native protein substrates in conjunction with ClpP1P2, but neither mediates protein degradation with just ClpP1 or ClpP2. ClpP1P2 alone has negligible peptidase activity, but is strongly stimulated by translocation of protein substrates into ClpP1P2 by either AAA+ partner. Interestingly, our results support a model in which both binding of a AAA+ partner and protein-substrate delivery are required to stabilize active ClpP1P2. Our model has implications for therapeutically targeting ClpP1P2 in dormant M. tuberculosis, and our reconstituted systems should facilitate identification of novel Clp protease inhibitors and activators. PMID:24976069

  9. Fall of blood ionized calcium on watching a provocative TV program and its prevention by active absorbable algal calcium (AAA Ca).

    PubMed

    Fujita, T; Ohgitani, S; Nomura, M

    1999-01-01

    In December 1997, more than 680 children developed convulsive seizures while watching a notorious audiovisually provocative TV program, "Pocket Monster." Emotional stimulation via hyperventilation may cause respiratory alkalosis, fall of blood ionized calcium (Ca), and sensitization of the nervous system to excessive emotional stress. A study was therefore undertaken to follow the changes of blood ionized Ca in eight healthy volunteers after watching the "Pocket Monster" and also a quiet program, "Classical Music," as a control for 20min from 4 P.M. Although neither marked hyperventilation nor convulsions developed in any of these adult volunteers, blood ionized Ca showed a significantly more pronounced fall during and after watching "Pocket Monster," and their plasma intact parathyroid hormone (iPTH) was significantly higher 120min after the beginning of "Pocket Monster" than the "Classical Music" program. Plasma total Ca, pH, and albumin were free of detectable changes. Ingestion of 600mg Ca as active absorbable algal Ca (AAA Ca) with high bioavailability completely prevented the fall of ionized Ca and suppressed iPTH. Plama osteocalcin was also significantly suppressed after ingestion of AAA Ca. It may be worthwhile to ingest AAA Ca before anticipated emotional stress such as watching a provocative TV program to prevent possible neuromuscular instability. PMID:10340641

  10. Air travel of patients with abdominal aortic aneurysm: urgent air medical evacuation and nonurgent commercial air repatriation.

    PubMed

    Barros, Andrew; Haffner, Faith; Duchateau, François-Xavier; Huff, J Stephen; Verner, Laurent; O'Connor, Robert E; Brady, William J

    2014-01-01

    Abdominal aortic aneurysm (AAA) presents across a spectrum of severity. Although some resources suggest a theoretic risk for rupture related to air travel, this claim remains unproven. In fact, there are little data from which to make evidence-based recommendations. Air medical evacuation of a patient with either an AAA at risk of imminent rupture or status post recent rupture can be performed, assuming that local surgical care is not available and that transfer is taking the patient to a higher level of medical intervention. Furthermore, medical opinion suggests that patients with asymptomatic and/or surgically corrected AAA can safely travel by commercial aircraft for nonurgent reasons, assuming that other issues including postoperative needs are appropriately addressed. In this discussion, answers to the following issues are sought: flight safety for urgent evacuation and nonurgent repatriation scenarios, waiting time to fly nonurgently after AAA diagnosis, and the need for medical accompaniment. PMID:24787514

  11. The biaxial biomechanical behavior of abdominal aortic aneurysm tissue.

    PubMed

    O'Leary, Siobhan A; Healey, Donagh A; Kavanagh, Eamon G; Walsh, Michael T; McGloughlin, Tim M; Doyle, Barry J

    2014-12-01

    Rupture of the abdominal aortic aneurysm (AAA) occurs when the local wall stress exceeds the local wall strength. Knowledge of AAA wall mechanics plays a fundamental role in the development and advancement of AAA rupture risk assessment tools. Therefore, the aim of this study is to evaluate the biaxial mechanical properties of AAA tissue. Multiple biaxial test protocols were performed on AAA samples harvested from 28 patients undergoing open surgical repair. Both the Tangential Modulus (TM) and stretch ratio (λ) were recorded and compared in both the circumferential (ϴ) and longitudinal (L) directions at physiologically relevant stress levels, the influence of patient specific factors such as sex, age AAA diameter and status were examined. The biomechanical response was also fit to a hyperplastic material model. The AAA tissue was found to be anisotropic with a greater tendency to stiffen in the circumferential direction compared to the longitudinal direction. An anisotropic hyperelastic constitutive model represented the data well and the properties were not influenced by the investigated patient specific factors however, a future study utilizing a larger cohort of patients is warranted to confirm these findings. This work provides further insights on the biomechanical behavior of AAA and may be useful in the development of more reliable rupture risk assessment tools. PMID:25201606

  12. Chronic obstructive pulmonary disease effect on the prevalence and postoperative outcome of abdominal aortic aneurysms: A meta-analysis.

    PubMed

    Xiong, Jiang; Wu, Zhongyin; Chen, Chen; Guo, Wei

    2016-01-01

    Epidemiologic evidence suggested chronic obstructive pulmonary disease (COPD) might increase risk for abdominal aortic aneurysm (AAA). However, the association between COPD and AAA remains inconclusive. We searched PubMed and Cochrane databases until June 2015. Forty-eight articles were included for meta-analysis. COPD was found to be positively associated with AAA, regardless of study design and smoking status. AAA mortality is higher among COPD patients compared with non-COPD patients (postoperative [adjusted OR 2.11; 95% CI 1.33-3.34]; long-term [adjusted OR 1.70; 95% CI 1.37-2.12]). But the association between postoperative mortality and COPD was not found to be significant in patients underwent endovascular aneurysm repair (mixed OR 2.53; 95% CI 0.70-9.18). Rupture AAA may increase the postoperative mortality in COPD patients (rupture [adjusted OR 4.75; 95% CI 2.07-10.89]; non-rupture [adjusted OR 1.97; 95% CI 1.11-3.49]). The AAA postoperative morbidity was found to be positively associated with COPD (adjusted OR 1.59; 95% CI 1.14-2.21). Increased COPD severity may increase the long-term mortality (medical versus oxygen dependent: [OR 1.26; 95% CI 1.07-1.49] versus [OR 2.79; 95% CI 2.24-3.49]). In conclusion, COPD may increase the risk of AAA, morbidity and mortality of AAA patients underwent endovascular aortic repair. PMID:27112336

  13. Creep and rupture of an ODS alloy with high stress rupture ductility. [Oxide Dispersion Strengthened

    NASA Technical Reports Server (NTRS)

    Mcalarney, M. E.; Arsons, R. M.; Howson, T. E.; Tien, J. K.; Baranow, S.

    1982-01-01

    The creep and stress rupture properties of an oxide (Y2O3) dispersion strengthened nickel-base alloy, which also is strengthened by gamma-prime precipitates, was studied at 760 and 1093 C. At both temperatures, the alloy YDNiCrAl exhibits unusually high stress rupture ductility as measured by both elongation and reduction in area. Failure was transgranular, and different modes of failure were observed including crystallographic fracture at intermediate temperatures and tearing or necking almost to a chisel point at higher temperatures. While the rupture ductility was high, the creep strength of the alloy was low relative to conventional gamma prime strengthened superalloys in the intermediate temperature range and to ODS alloys in the higher temperature range. These findings are discussed with respect to the alloy composition; the strengthening oxide phases, which are inhomogeneously dispersed; the grain morphology, which is coarse and elongated and exhibits many included grains; and the second phase inclusion particles occurring at grain boundaries and in the matrix. The creep properties, in particular the high stress dependencies and high creep activation energies measured, are discussed with respect to the resisting stress model of creep in particle strengthened alloys.

  14. Antenatal Corticosteroids for Preterm Premature Rupture of Membranes: Single or Repeat Course?

    PubMed Central

    Brookfield, Kathleen F.; El-Sayed, Yasser Y.; Chao, Lisa; Berger, Victoria; Naqvi, Mariam; Butwick, Alexander J.

    2015-01-01

    Objective The aim of this article is to determine the risk of maternal chorioamnionitis and neonatal morbidity in women with preterm premature rupture of membranes (PPROM) exposed to one corticosteroid course versus a single repeat corticosteroid steroid course. Study Design Secondary analysis of a cohort of women with singleton pregnancies and PPROM. The primary outcome was a clinical diagnosis of maternal chorioamnionitis. Using multivariate logistic regression, we controlled for maternal age, race, body mass index, diabetes, gestational age at membrane rupture, preterm labor, and antibiotic administration. Neonatal morbidities were compared between groups controlling for gestational age at delivery. Results Of 1,652 women with PPROM, 1,507 women received one corticosteroid course and 145 women received a repeat corticosteroid course. The incidence of chorioamnionitis was similar between groups (single course = 12.3% vs. repeat course = 11.0%; p = 0.8). Women receiving a repeat corticosteroid course were not at increased risk of chorioamnionitis (adjusted odds ratio, 1.28; 95% confidence interval, 0.69–2.14). A repeat course of steroids was not associated with an increased risk of any neonatal morbidity. Conclusion Compared with a single steroid course, our findings suggest that the risk of maternal chorioamnionitis or neonatal morbidity may not be increased for women with PPROM receiving a repeat corticosteroid course. PMID:25545441

  15. Implementing the effect of the rupture directivity on PSHA maps: Application to the Marmara Region (Turkey)

    NASA Astrophysics Data System (ADS)

    Herrero, Andre; Spagnuolo, Elena; Akinci, Aybige; Pucci, Stefano

    2016-04-01

    In the present study we attempted to improve the seismic hazard assessment taking into account possible sources of epistemic uncertainty and the azimuthal variability of the ground motions which, at a particular site, is significantly influenced by the rupture mechanism and the rupture direction relative to the site. As a study area we selected Marmara Region (Turkey), especially the city of Istanbul which is characterized by one of the highest levels of seismic risk in Europe and the Mediterranean region. The seismic hazard in the city is mainly associated with two active fault segments which are located at about 20-30 km south of Istanbul. In this perspective first we proposed a methodology to incorporate this new information such as nucleation point in a probabilistic seismic hazard analysis (PSHA) framework. Secondly we introduced information about those fault segments by focusing on the fault rupture characteristics which affect the azimuthal variations of the ground motion spatial distribution i.e. source directivity effect and its influence on the probabilistic seismic hazard analyses (PSHA). An analytical model developed by Spudich and Chiou (2008) is used as a corrective factor that modifies the Next Generation Attenuation (NGA, Power et al. 2008) ground motion predictive equations (GMPEs) introducing rupture related parameters that generally lump together into the term directivity effect. We used the GMPEs as derived by the Abrahamson and Silva (2008) and the Boore and Atkinson (2008); our results are given in terms of 10% probability of exceedance of PSHA (at several periods from 0.5 s to 10 s) in 50 years on rock site condition; the correction for directivity introduces a significant contribution to the percentage ratio between the seismic hazards computed using the directivity model respect to the seismic hazard standard practice. In particular, we benefited the dynamic simulation from a previous study (Aochi & Utrich, 2015) aimed at evaluating the

  16. Blunt traumatic cardiac rupture. A 5-year experience.

    PubMed

    Brathwaite, C E; Rodriguez, A; Turney, S Z; Dunham, C M; Cowley, R

    1990-12-01

    Blunt traumatic cardiac rupture is associated with a high rate of mortality. A review of the computerized trauma registry (1983 to 1988) identified 32 patients with this injury (ages 19 to 65 years; mean age, 39.5 years; 21 men and 11 women). Twenty-one patients (65.6%) were injured in vehicular crashes, 3 (9.4%) in pedestrian accidents, 3 (9.4%) in motorcycle accidents; 3 (9.4%) sustained crush injury; 1 (3.1%) was injured by a fall; and 1 (3.1%) was kicked in the chest by a horse. Anatomic injuries included right atrial rupture (13[40.6%]), left atrial rupture (8 [25%]), right ventricular rupture (10[31.3%]), left ventricular rupture (4[12.5%]), and rupture of two cardiac chambers (3 [9.4%]). Diagnosis was made by thoracotomy in all 20 patients presenting in cardiac arrest. In the remaining 12 patients, the diagnosis was established in seven by emergency left anterolateral thoracotomy and in five by subxyphoid pericardial window. Seven of these 12 patients (58.3%) had clinical cardiac tamponade and significant upper torso cyanosis. The mean Injury Severity Score (ISS), Trauma Score (TS), and Glasgow Coma Scale (GCS) score were 33.8, 13.2, and 14.3, respectively, among survivors and 51.5, 8.3, and 7.0 for nonsurvivors. The overall mortality rate was 81.3% (26 of 32 patients), the only survivors being those presenting with vital signs (6 of 12 patients [50%]). All patients with rupture of two cardiac chambers or with ventricular rupture died. The mortality rate from myocardial rupture is very high. Rapid prehospital transportation, a high index of suspicion, and prompt surgical intervention contribute to survival in these patients. PMID:2256761

  17. Experimental verification of the Acuros XB and AAA dose calculation adjacent to heterogeneous media for IMRT and RapidArc of nasopharygeal carcinoma

    SciTech Connect

    Kan, Monica W. K.; Leung, Lucullus H. T.; So, Ronald W. K.; Yu, Peter K. N.

    2013-03-15

    Purpose: To compare the doses calculated by the Acuros XB (AXB) algorithm and analytical anisotropic algorithm (AAA) with experimentally measured data adjacent to and within heterogeneous medium using intensity modulated radiation therapy (IMRT) and RapidArc{sup Registered-Sign} (RA) volumetric arc therapy plans for nasopharygeal carcinoma (NPC). Methods: Two-dimensional dose distribution immediately adjacent to both air and bone inserts of a rectangular tissue equivalent phantom irradiated using IMRT and RA plans for NPC cases were measured with GafChromic{sup Registered-Sign} EBT3 films. Doses near and within the nasopharygeal (NP) region of an anthropomorphic phantom containing heterogeneous medium were also measured with thermoluminescent dosimeters (TLD) and EBT3 films. The measured data were then compared with the data calculated by AAA and AXB. For AXB, dose calculations were performed using both dose-to-medium (AXB{sub Dm}) and dose-to-water (AXB{sub Dw}) options. Furthermore, target dose differences between AAA and AXB were analyzed for the corresponding real patients. The comparison of real patient plans was performed by stratifying the targets into components of different densities, including tissue, bone, and air. Results: For the verification of planar dose distribution adjacent to air and bone using the rectangular phantom, the percentages of pixels that passed the gamma analysis with the {+-} 3%/3mm criteria were 98.7%, 99.5%, and 97.7% on the axial plane for AAA, AXB{sub Dm}, and AXB{sub Dw}, respectively, averaged over all IMRT and RA plans, while they were 97.6%, 98.2%, and 97.7%, respectively, on the coronal plane. For the verification of planar dose distribution within the NP region of the anthropomorphic phantom, the percentages of pixels that passed the gamma analysis with the {+-} 3%/3mm criteria were 95.1%, 91.3%, and 99.0% for AAA, AXB{sub Dm}, and AXB{sub Dw}, respectively, averaged over all IMRT and RA plans. Within the NP region where

  18. Combined uterine and urinary bladder rupture: an unusual complication of obstructed labor in a primigravida

    PubMed Central

    Takai, Idris Usman; Abubakar, Abdulkadir

    2016-01-01

    Background Combined uterine and urinary bladder rupture following prolonged obstructed labor is indeed a momentous uro-obstetric emergency. The urinary bladder involvement is distinctly rare in the absence of factors that predispose the bladder to be adherent to the lower uterine segment and is quite unusual in a primigravida. Objective To report a rare case of uterine rupture involving urinary bladder secondary to a prolonged obstructed labor in a primigravida from a low resource setting. Case A 17-year-old married unbooked primigravida who presented with a 3-day history of spontaneous onset of labor at term that was initially managed at home and later in a primary health care center where she had fundal pressure and oxytocin augmentation, respectively. The labor was complicated by combined uterine and urinary bladder rupture with sepsis. She was resuscitated and had exploratory laparotomy with uterine and urinary bladder repair. The postoperative period was uneventful and she was followed-up at the gynecology and family planning clinics. Conclusion There is a need for community reawakening on the inherent risks of teenage pregnancy, bad obstetric practices, and unsupervised pregnancy, labor, and delivery, particularly in the rural settings as in the index patient. A high index of suspicion and prompt appropriate intervention will reduce the sequel of morbidity and occasional mortality from this predicament. PMID:27499647

  19. [Successful endovascular repair of a ruptured thoracoabdominal aortic aneurysm with severe mural thrombus].

    PubMed

    Nakao, Yoshihisa; Akagi, Haruhiko; Irie, Hiroshi; Sakaguchi, Shoji; Sakai, Kei

    2014-11-01

    A 51-year-old man was transferred to our hospital on an emergency basis complaining of a sudden onset of severe left lumbar back pain. An emergency contrasted computed tomography showed a ruptured thoracoabdominal aortic aneurysm( rTAAA:Crawford classification type III). The ruptured site was near the aortic bifurcation, and the aneurysm had a relatively narrow segment with an extensive mural thrombus just below the renal arteries. Considering the high mortality of open surgery for the rTAAA and the poor general condition of the patient, we decided to perform endovascular aneurysm repair (EVAR) as a rescue procedure using the narrowed segment by the thrombus for a proximal landing zone. The abdominal part of the thoracoabdominal aortic aneurysm (TAAA) was successfully excluded with a stent graft to obtain complete hemostasis. The postoperative course was uneventful except for the need for hemodialysis. Even though there is a risk of developing late type 1 endoleak, this procedure can be a feasible option as a rescue procedure or a bridge to radical open surgery for ruptured TAAA in a specially anatomical setting like this case. PMID:25391465

  20. Rupture Synchronicity in Complex Fault Systems

    NASA Astrophysics Data System (ADS)

    Milner, K. R.; Jordan, T. H.

    2013-12-01

    While most investigators would agree that the timing of large earthquakes within a fault system depends on stress-mediated interactions among its elements, much of the debate relevant to time-dependent forecasting has been centered on single-fault concepts, such as characteristic earthquake behavior. We propose to broaden this discussion by quantifying the multi-fault concept of rupture synchronicity. We consider a finite set of small, fault-spanning volumes {Vk} within a fault system of arbitrary (fractal) complexity. We let Ck be the catalog of length tmax comprising Nk discrete times {ti(k)} that mark when the kth volume participates in a rupture of magnitude > M. The main object of our analysis is the complete set of event time differences {τij(kk') = ti(k) - tj(k')}, which we take to be a random process with an expected density function ρkk'(t). When k = k', we call this function the auto-catalog density function (ACDF); when k ≠ k', we call it the cross-catalog density function (CCDF). The roles of the ACDF and CCDF in synchronicity theory are similar to those of autocorrelation and cross-correlation functions in time-series analysis. For a renewal process, the ACDF can be written in terms of convolutions of the interevent-time distribution, and many of its properties (e.g., large-t asymptote) can be derived analytically. The interesting information in the CCDF, like that in the ACDF, is concentrated near t = 0. If two catalogs are completely asynchronous, the CCDF collapses to an asymptote given by the harmonic mean of the ACDF asymptotes. Synchronicity can therefore be characterized by the variability of the CCDF about this asymptote. The brevity of instrumental catalogs makes the identification of synchronicity at large M difficult, but we will illustrate potentially interesting behaviors through the analysis of a million-year California catalog generated by the earthquake simulator, RSQSim (Deiterich & Richards-Dinger, 2010), which we sampled at a

  1. Ruptured ileocolic artery aneurysm: an unusual cause of hemoperitoneum.

    PubMed

    Siddiqui, Zakaur R; Yousif, Omer F; Halliday, Mark W; Hubaishah, Nasser A; Adam, Khalid A

    2012-01-01

    Ruptured aneurysm of a branch of ileocolic artery is a rare finding and is an unusual cause of haemoperitoneum. Rapid diagnosis, and surgical or endovascular intervention are necessary to avoid devastating consequences and high mortality rates following an emergency operation after rupture. Resection is a good choice for surgical intervention for some aneurysms that are not suitable for endovascular repair. This report describes the case of a middle-aged man with a ruptured superior mesenteric artery branch aneurysm and his subsequent surgical management. PMID:23006464

  2. Ruptured Ileocolic Artery Aneurysm: An Unusual Cause of Hemoperitoneum

    PubMed Central

    Siddiqui, Zakaur R.; Yousif, Omer F.; Halliday, Mark W.; Hubaishah, Nasser A.; Adam, Khalid A.

    2012-01-01

    Ruptured aneurysm of a branch of ileocolic artery is a rare finding and is an unusual cause of haemoperitoneum. Rapid diagnosis, and surgical or endovascular intervention are necessary to avoid devastating consequences and high mortality rates following an emergency operation after rupture. Resection is a good choice for surgical intervention for some aneurysms that are not suitable for endovascular repair. This report describes the case of a middle-aged man with a ruptured superior mesenteric artery branch aneurysm and his subsequent surgical management. PMID:23006464

  3. Rupture of the triceps tendon - A case series.

    PubMed

    Jaiswal, Atin; Kacchap, Naiman-Deep; Tanwar, Yashwant-Singh; Kumar, Devendra; Kumar, Birendra

    2016-08-01

    Triceps rupture is the least common among all tendon injuries. The usual mechanism of injury is a fall on an outstretched hand, although direct contact injuries have also been reported to cause this injury. The diagnosis of acute triceps tendon rupture may be missed, which can result in prolonged disability and delayed operative management. We presented three cases of acute triceps tendon rupture each at different site showing the spectrum of injury to the muscle and mechanism of injury and management were also discussed. PMID:27578383

  4. Infective splenic rupture presenting with symptoms of a pulmonary embolism.

    PubMed

    Shah, M; Muquit, S; Azam, B

    2008-12-01

    Splenic rupture following infectious mononucleosis is rare. The case history is presented of a man who presented with sudden onset pleuritic left chest pain. An ultrasound scan of the abdomen showed an enlarged spleen with an abnormal echo pattern and a CT scan of the abdomen showed severe splenic rupture. The patient remembered that he had been unwell 2 weeks earlier with flu-like symptoms and enlarged cervical lymph nodes. Serological examination was positive for Ebstein-Barr virus, confirming the diagnosis of splenic rupture following splenomegaly due to infectious mononucleosis. Management was initially conservative but he became haemodynamically unstable and an emergency splenectomy was performed. PMID:19033515

  5. Frictional melting during the rupture of the 1994 bolivian earthquake

    PubMed

    Kanamori; Anderson; Heaton

    1998-02-01

    The source parameters of the 1994 Bolivian earthquake (magnitude Mw = 8.3) suggest that the maximum seismic efficiency eta was 0.036 and the minimum frictional stress was 550 bars. Thus, the source process was dissipative, which is consistent with the observed slow rupture speed, only 20% of the local S-wave velocity. The amount of nonradiated energy produced during the Bolivian rupture was comparable to, or larger than, the thermal energy of the 1980 Mount St. Helens eruption and was sufficient to have melted a layer as thick as 31 centimeters. Once rupture was initiated, melting could occur, which reduces friction and promotes fault slip. PMID:9452378

  6. The rupture of a single liquid aluminium alloy film.

    PubMed

    Heim, K; García-Moreno, F; Vinod Kumar, G S; Rack, A; Banhart, J

    2014-07-14

    The present study is based on the idea of understanding the rupture of films in metal foams by studying free standing metallic films as a model system. Liquid dynamics, the velocity of the rupturing material as well as the behaviour of ceramic particles inside the melt were analysed optically ex situ and by synchrotron X-ray radiography in situ. It was found that the resistance of films to rupture is mainly based on the interaction between solid particles and an immobile oxide skin, the formation of which depends on the oxygen content of the surrounding atmosphere and the presence of magnesium. PMID:24854899

  7. A yeast gene, MGS1, encoding a DNA-dependent AAA(+) ATPase is required to maintain genome stability.

    PubMed

    Hishida, T; Iwasaki, H; Ohno, T; Morishita, T; Shinagawa, H

    2001-07-17

    Changes in DNA superhelicity during DNA replication are mediated primarily by the activities of DNA helicases and topoisomerases. If these activities are defective, the progression of the replication fork can be hindered or blocked, which can lead to double-strand breaks, elevated recombination in regions of repeated DNA, and genome instability. Hereditary diseases like Werner's and Bloom's Syndromes are caused by defects in DNA helicases, and these diseases are associated with genome instability and carcinogenesis in humans. Here we report a Saccharomyces cerevisiae gene, MGS1 (Maintenance of Genome Stability 1), which encodes a protein belonging to the AAA(+) class of ATPases, and whose central region is similar to Escherichia coli RuvB, a Holliday junction branch migration motor protein. The Mgs1 orthologues are highly conserved in prokaryotes and eukaryotes. The Mgs1 protein possesses DNA-dependent ATPase and single-strand DNA annealing activities. An mgs1 deletion mutant has an elevated rate of mitotic recombination, which causes genome instability. The mgs1 mutation is synergistic with a mutation in top3 (encoding topoisomerase III), and the double mutant exhibits severe growth defects and markedly increased genome instability. In contrast to the mgs1 mutation, a mutation in the sgs1 gene encoding a DNA helicase homologous to the Werner and Bloom helicases suppresses both the growth defect and the increased genome instability of the top3 mutant. Therefore, evolutionarily conserved Mgs1 may play a role together with RecQ family helicases and DNA topoisomerases in maintaining proper DNA topology, which is essential for genome stability. PMID:11459965

  8. Hansenula polymorpha Pex1p and Pex6p are peroxisome-associated AAA proteins that functionally and physically interact.

    PubMed

    Kiel, J A; Hilbrands, R E; van der Klei, I J; Rasmussen, S W; Salomons, F A; van der Heide, M; Faber, K N; Cregg, J M; Veenhuis, M

    1999-08-01

    We have cloned the Hansenula polymorpha PEX1 and PEX6 genes by functional complementation of the corresponding peroxisome-deficient (pex) mutants. The gene products, HpPex1p and HpPex6p, are ATPases which both belong to the AAA protein family. Cells deleted for either gene (Deltapex1 or Deltapex6) were characterized by the presence of small peroxisomal remnants which contained peroxisomal membrane proteins and minor amounts of matrix proteins. The bulk of the matrix proteins, however, resided in the cytosol. In cell fractionation studies HpPex1p and HpPex6p co-sedimented with the peroxisomal membrane protein HpPex3p in both wild-type cells and in Deltapex4, Deltapex8 or Deltapex14 cells. Both proteins are loosely membrane-bound and face the cytosol. Furthermore, HpPex1p and HpPex6p physically and functionally interact in vivo. Overexpression of PEX6 resulted in defects in peroxisomal matrix protein import. By contrast, overexpression of PEX1 was not detrimental to the cells. Interestingly, co-overproduction of HpPex1p rescued the protein import defect caused by HpPex6p overproduction. Overproduced HpPex1p and HpPex6p remained predominantly membrane-bound, but only partially co-localized with the peroxisomal membrane protein HpPex3p. Our data indicate that HpPex1p and HpPex6p function in a protein complex associated with the peroxisomal membrane and that overproduced, mislocalized HpPex6p prevents HpPex1p from reaching its site of activity. PMID:10455230

  9. Frequency of concomitant ischemic heart disease and risk factor analysis for an early postoperative myocardial infarction after elective abdominal aortic aneurysm repair

    PubMed Central

    Han, Seung Rim; Heo, Seon-Hee; Woo, Shin-Young; Park, Yang Jin; Kim, Dong Ik; Yang, Jeonghoon; Choi, Seung-Hyuk; Kim, Duk-Kyung

    2016-01-01

    Purpose We aimed to see the frequency of concomitant ischemic heart disease (IHD) in Korean patients with abdominal aortic aneurysm (AAA) and to determine risk factors for an early postoperative acute myocardial infarction (PAMI) after elective open or endovascular AAA repair. Methods We retrospectively reviewed a database of patients who underwent elective AAA repair over the past 11 years. Patients were classified into 3 groups: control group; group I, medical IHD treatment; group II, invasive IHD treatment. Rates of PAMI and mortality at 30 days were compiled and compared between groups according to the type of AAA repair. Results Six hundred two elective repairs of infrarenal or juxtarenal AAAs were enrolled in this study. The patients were classified into control group (n = 398, 66.1%), group I (n = 73, 12.1%) and group II (n = 131, 21.8%). PAMI developed more frequently after open surgical repair (OSR) than after endovascular aneurysm repair (EVAR) (5.4% vs. 1.3%, P = 0.012). In OSR patients (n = 373), PAMI developed 2.1% in control group, 18.0% in group I and 7.1% in group II (P < 0.001). In EVAR group (n = 229), PAMI developed 0.6% in control group, 4.3% in group I and 2.2% in group II (P = 0.211). On the multivariable analysis of risk factors of PAMI, PAMI developed more frequently in patients with positive functional stress test. Conclusion The prevalence of concomitant IHD was 34% in Korean AAA patients. The risk of PAMI was significantly higher after OSR compared to EVAR and in patients with IHD compared to control group. Though we found some risk factors for PAMI, these were not applied to postoperative mortality rate. PMID:26942161

  10. Is Cadmium Exposure Associated with the Burden, Vulnerability and Rupture of Human Atherosclerotic Plaques?

    PubMed Central

    Sallsten, Gerd; Lundh, Thomas; Barregard, Lars

    2015-01-01

    The general population is exposed to cadmium from food and smoking. Cadmium is a widely spread toxic pollutant that seems to be associated with cardiovascular diseases, although little is known if it contributes to the occurrence of atherosclerotic plaques and the process whereby plaques become vulnerable and are prone to rupture. We tested the hypotheses that cadmium exposure is associated not only with an increased subclinical burden of atherosclerotic plaques in different vascular territories and early signs of plaque vulnerability, but also with cadmium content and plaque-rupture in the clinical phase of the disease. Ultrasound technique was used to measure plaque prevalence and echogenicity in the carotid and femoral arteries in a population sample of women (n = 599) in whom blood cadmium was measured. In addition cadmium was measured in snap-frozen endarterectomies and whole blood obtained from patients who were referred to surgery because of symptomatic carotid plaques (n = 37). Sixteen endarterectomies were divided into three parts corresponding to different flow conditions and plaque vulnerability. In the population sample blood cadmium was associated with the number of vascular territories with plaques (p = 0.003 after adjustment for potential confounders). The cadmium concentrations in symptomatic plaques were 50-fold higher in plaque tissue than in blood. Cadmium levels in blood and plaque correlated, also after adjustment for smoking and other cardiovascular risk factors (p<0.001). Compared with the other parts of the plaque, the cadmium content was double as high in the part where plaque rupture usually occurs. In conclusion, the results show that cadmium exposure is associated with the burden of subclinical atherosclerosis in middle-aged women with different degrees of glucose tolerance, and that the content of cadmium in symptomatic plaques in patients is related to that in blood, but much higher, and preferentially located in the part of plaque

  11. Use of the Pipeline Embolization Device to Treat Recently Ruptured Dissecting Cerebral Aneurysms

    PubMed Central

    Chan, Robert S.K.; Mak, Calvin H.K.; Wong, Alain K.S.; Chan, Kwong Yau; Leung, Kar Ming

    2014-01-01

    Summary The Pipeline embolization device (PED) is one of the flow-diverting stents approved for the treatment of unruptured large or wide-necked cerebral aneurysms in 2011 1. Its use has now been extended to the treatment of recently ruptured dissecting cerebral aneurysm, carotid pseudoaneurysm from radiation injury, and blister aneurysms 2,3. We aimed to evaluate the effectiveness of utilizing the PED as a primary treatment for ruptured dissecting intracranial aneurysms. A single center retrospective review was conducted for all patients primarily treated with PED for acute subarachnoid hemorrhage (SAH) from ruptured dissecting cerebral aneurysms between December 2010 and February 2013. Patients were followed up with CT angiogram (CTA) or digital subtraction angiogram (DSA). Eight patients with a total of eight dissecting aneurysms were identified. The mean duration from SAH to treatment was 2.5 days. Six of the aneurysms arose from vertebral arteries and two from the basilar artery. Immediate check-DSA confirmed satisfactory contrast stasis in all eight cases, and complete aneurysmal obliteration was achieved at six months. There were two (25%) procedure-related complications, but no major procedure-related complications, such as thromboembolic events or rebleeding from aneurysm were encountered. The PED is a feasible treatment option for ruptured dissecting cerebral aneurysms in acute phase. According to our experience, using PED as flow-diverters in acute SAH does not significantly increase the complication risks or mortality rate if the antiplatelet regime is carefully monitored. Future studies shall evaluate the optimal antiplatelet regimen for using the PED in the acute phase. PMID:25207906

  12. Bulkhead rupture disc for solid propellant missiles

    SciTech Connect

    Hibler, D.R. Sr.; Sigle, S.P. Jr.

    1988-04-19

    A missile bulkhead rupture disc assembly for disposition between a first stage of propellant and a second stage of propellant and for enabling release of the second stage of propellant subsequent to release of the first stage of propellant is described comprising: a generally circular element comprised of a frangible material and having a first burst pattern with a line of weakness completely circumscribing a central portion of the element. The central portion of the element having structure defines an aperture. The element has a second burst pattern comprising lines of weakness each extending in a substantially radial direction outwardly from the line of weakness of the first burst pattern. Each adjacent pair of the lines of weakness of the second burst pattern is spaced from each other and defines generally sector-shaped segments of the elements. The frangible material of the element has a tensile strength of a certain, first value in the vicinity of the line of weakness of the first burst pattern, and the frangible material of the element has a tensile strength in the vicinity of the lines of weakness of the second burst pattern of a second value which is higher than the first certain value.

  13. Stress-rupture strength of alloy 718

    SciTech Connect

    Kennedy, R.L.; Cao, W.D.; Thomas, W.M.

    1996-03-01

    Alloy 718 is the most widely used of the nickel-base superalloys in aerospace applications such as compressor and turbine disks, cases, compressor blades and fasteners in aircraft gas-turbine engines. Since the development of the superalloy by Inco Alloys International over 30 years ago, researchers have made many slight modifications in chemical composition, and have refined process techniques to achieve further improvements in performance. Relatively little information on the effects of phosphorus has been published, and the available information is contradictory. However, phosphorus in superalloys is generally considered detrimental, and by specification is controlled to a low maximum value (0.015% max, for example, in AMS5662 E). This lack of data is the basis of a study by Teledyne Allvac to determine the effects of the interaction of phosphorus, boron, and carbon on the mechanical properties, processing characteristics, and microstructure of Allvac 718. Results show that a significant improvement in stress-rupture properties over those of a commercial Alloy 718 material is possible by optimizing phosphorus, boron, and carbon additions.

  14. Extracellular Matrix Dynamics and Fetal Membrane Rupture

    PubMed Central

    Strauss,, Jerome F.

    2013-01-01

    The extracellular matrix (ECM) plays an important role in determining cell and organ function: (1) it is an organizing substrate that provides tissue tensile strength; (2) it anchors cells and influences cell morphology and function via interaction with cell surface receptors; and (3) it is a reservoir for growth factors. Alterations in the content and the composition of the ECM determine its physical and biological properties, including strength and susceptibility to degradation. The ECM components themselves also harbor cryptic matrikines, which when exposed by conformational change or proteolysis have potent effects on cell function, including stimulating the production of cytokines and matrix metalloproteinases (MMPs). Collectively, these properties of the ECM reflect a dynamic tissue component that influences both tissue form and function. This review illustrates how defects in ECM synthesis and metabolism and the physiological process of ECM turnover contribute to changes in the fetal membranes that precede normal parturition and contribute to the pathological events leading to preterm premature rupture of membranes (PPROM). PMID:22267536

  15. Extracellular matrix dynamics and fetal membrane rupture.

    PubMed

    Strauss, Jerome F

    2013-02-01

    The extracellular matrix (ECM) plays an important role in determining cell and organ function: (1) it is an organizing substrate that provides tissue tensile strength; (2) it anchors cells and influences cell morphology and function via interaction with cell surface receptors; and (3) it is a reservoir for growth factors. Alterations in the content and the composition of the ECM determine its physical and biological properties, including strength and susceptibility to degradation. The ECM components themselves also harbor cryptic matrikines, which when exposed by conformational change or proteolysis have potent effects on cell function, including stimulating the production of cytokines and matrix metalloproteinases (MMPs). Collectively, these properties of the ECM reflect a dynamic tissue component that influences both tissue form and function. This review illustrates how defects in ECM synthesis and metabolism and the physiological process of ECM turnover contribute to changes in the fetal membranes that precede normal parturition and contribute to the pathological events leading to preterm premature rupture of membranes (PPROM). PMID:22267536

  16. [Bronchial rupture in blunt thoracic trauma].

    PubMed

    López Espadas, F; Zabalo, M; Encinas, M; Díaz Regañón, G; Pagola, M A; González Fernández, C

    2000-12-01

    In closed chest trauma, bronchial rupture is an unusual but potentially serious complication, with an associated mortality rate of 30%. Recent decades have seen an increase in incidence parallel to greater use of transport. Eighty percent of injuries are located 2.5 cm from the carina. Diagnosis is based on clinical signs, imaging and bronchoscopy. Subcutaneous emphysema and respiratory insufficiency are the most common findings. Images show the presence of pneumothorax, pneumomediastinum or both. Bronchoscopy is the diagnostic method of choice and must be performed early. Treatment consists of reestablishing anatomical continuity of the tracheobronchial tree by surgical repair if the lesion affects more than a third of the circumference and/or pneumothorax is not resolved after two chest drainages. This type of injury should be recognized and treated early, both to restore lung function and to prevent associated complications caused by delay. However, initial findings are seldom specific, requiring the physician to display a high degree of suspicion and explaining why diagnosis often comes late. PMID:11171438

  17. Distal embolization as a presenting symptom of aortic aneurysms.

    PubMed

    Baxter, B T; McGee, G S; Flinn, W R; McCarthy, W J; Pearce, W H; Yao, J S

    1990-08-01

    The records of 302 patients who underwent abdominal aortic aneurysm (AAA) repair between 1985 and 1990 were reviewed. Two hundred and forty-eight patients (82%) were asymptomatic, while 32 patients (11%) had ruptured aneurysms. During this period, 15 patients (5%) presented with distal embolization as the first manifestation of their AAA. The preoperative embolic event resulted in limb-threatening ischemia in 3 patients, digital ischemia in 11, and calf myonecrosis in 1. CT scan was performed in 14 of 15 patients demonstrating irregular, heterogeneous thrombus within the AAA. Only two of the AAAs were larger than 5 cm. Angiography demonstrated occlusive lesions but was not diagnostic for AAA in seven patients and resulted in three episodes of embolization. AAA was repaired with a tube graft in 4 patients while a bifurcated graft was required in 11 patients for aneurysmal (in 4 patients) and occlusive disease (in 7 patients) of the iliac arteries. All cases employed a transperitoneal approach, systemic heparin, and distal occlusion prior to aortic clamping. Complications included three major (below-knee) and five minor amputations, developing or worsening renal failure in five patients (33%), and death in two (13%). In comparison, mortality was 5% for elective repair and 66% for rupture during this same period. CT scan was safer and more informative than angiography. The morbidity of patients with AAA presenting with emboli is comparable with rupture. The risk of embolization does not correlate with size and indicates the potentially dangerous nature of small AAAs. PMID:2200293

  18. Co-existence of a rare dyspnea with pericardial diaphragmatic rupture and pericardial rupture: a case report.

    PubMed

    Öz, Necdet; Kargı, Ahmet Bülent; Zeybek, Arife

    2015-06-01

    Pericardial-diaphragmatic rupture is a rare condition which occurs after blunt trauma and involves the herniation of abdominal organs into the pericardium. A 77-year-old female patient presenting with complaints of palpitation and difficulty in breathing was admitted to the emergency room. Left lateral thoracotomy revealed the herniation of abdominal organs into the thorax. A pericardial-diaphragmatic rupture and a pericardial rupture were found to co-exist. The diaphragm and the pericardium were repaired primarily. The case is presented here because herniation of abdominal organs into the pleural cavity through the pericardium is a rare condition. PMID:26336505

  19. Co-existence of a rare dyspnea with pericardial diaphragmatic rupture and pericardial rupture: a case report

    PubMed Central

    Kargı, Ahmet Bülent; Zeybek, Arife

    2015-01-01

    Pericardial-diaphragmatic rupture is a rare condition which occurs after blunt trauma and involves the herniation of abdominal organs into the pericardium. A 77-year-old female patient presenting with complaints of palpitation and difficulty in breathing was admitted to the emergency room. Left lateral thoracotomy revealed the herniation of abdominal organs into the thorax. A pericardial-diaphragmatic rupture and a pericardial rupture were found to co-exist. The diaphragm and the pericardium were repaired primarily. The case is presented here because herniation of abdominal organs into the pleural cavity through the pericardium is a rare condition. PMID:26336505

  20. An update on the etiology of abdominal aortic aneurysms: implications for future diagnostic testing.

    PubMed

    Miner, Grace H; Faries, Peter L; Costa, Kevin D; Hanss, Basil G; Marin, Michael L

    2015-10-01

    Abdominal aortic aneurysm (AAA) disease is multifactorial with both environmental and genetic risk factors. The current research in AAA revolves around genetic profiles and expression studies in both human and animal models. Variants in genes involved in extracellular matrix degradation, inflammation, the renin-angiotensin system, cell growth and proliferation and lipid metabolism have been associated with AAA using a variety of study designs. However, the results have been inconsistent and without a standard animal model for validation. Thus, despite the growing body of knowledge, the specific variants responsible for AAA development, progression and rupture have yet to be determined. This review explores some of the more significant genetic studies to provide an overview of past studies that have influenced the current understanding of AAA etiology. Expanding our understanding of disease pathogenesis will inform research into novel diagnostics and therapeutics and ultimately to improve outcomes for patients with AAA. PMID:26401919

  1. Staged Management of a Ruptured Internal Mammary Artery Aneurysm

    PubMed Central

    Kwon, O Young; Kim, Gun Jik; Oh, Tak Hyuk; Lee, Young Ok; Lee, Sang Cjeol; Cho, Jun Yong

    2016-01-01

    The rupture of an internal mammary artery (IMA) aneurysm in a patient with type 1 neurofibromatosis (NF-1) is a rare but life-threatening complication requiring emergency management. A 50-year-old man with NF-1 was transferred to the emergency department of Kyungpook National University Hospital, where an IMA aneurysmal rupture and hemothorax were diagnosed and drained. The IMA aneurysmal rupture and hemothorax were successfully repaired by staged management combining endovascular treatment and subsequent video-assisted thoracoscopic surgery (VATS). The patient required cardiopulmonary cerebral resuscitation, the staged management of coil embolization, and a subsequent VATS procedure. This staged approach may be an effective therapeutic strategy in cases of IMA aneurysmal rupture. PMID:27066438

  2. [Spontaneous rupture of mediastinal cystic teratoma (case report)].

    PubMed

    Ege, Gürkan; Akman, Haluk; Kuzucu, Kismet; Kalayci, Göksel

    2004-06-01

    Teratomas are rare tumors in the mediastinum. Benign cystic teratomas of anterior mediastinum are rarely complicated by rupture into an adjacent body cavity. Such rupture, however, is usually associated with life-threatening complications. We present a case with spontaneous rupture of mediastinal cystic teratoma. The patient was evaluated with chest radiograph, computed tomography (CT) and magnetic resonance imaging (MRI). A complex mass including predominantly cystic components was detected in the left anterior mediastinum. After surgery, pathologic diagnosis was reported as mature cystic teratoma. High levels of amylase and lipase were detected in both the cystic fluid and serum. This finding supported the hypothesis of autolysis for the explanation of rupture. In addition, carbohydrate antigen (CA) 19-9, CA 125 and carcinoembryonic antigen (CEA) levels were high in the cystic fluid. PMID:15236127

  3. Staged Management of a Ruptured Internal Mammary Artery Aneurysm.

    PubMed

    Kwon, O Young; Kim, Gun Jik; Oh, Tak Hyuk; Lee, Young Ok; Lee, Sang Cjeol; Cho, Jun Yong

    2016-04-01

    The rupture of an internal mammary artery (IMA) aneurysm in a patient with type 1 neurofibromatosis (NF-1) is a rare but life-threatening complication requiring emergency management. A 50-year-old man with NF-1 was transferred to the emergency department of Kyungpook National University Hospital, where an IMA aneurysmal rupture and hemothorax were diagnosed and drained. The IMA aneurysmal rupture and hemothorax were successfully repaired by staged management combining endovascular treatment and subsequent video-assisted thoracoscopic surgery (VATS). The patient required cardiopulmonary cerebral resuscitation, the staged management of coil embolization, and a subsequent VATS procedure. This staged approach may be an effective therapeutic strategy in cases of IMA aneurysmal rupture. PMID:27066438

  4. Delayed aortic rupture resulting from postoperative superficial sternal wound infection

    PubMed Central

    Kim, Su Wan; Chang, Jee Won

    2016-01-01

    While deep sternal wound infection (DSWI) after cardiac surgery is a significant contributor to patient morbidity and mortality, superficial sternal wound infection (SSWI) mostly has a benign course. We report a mortality case of aortic rupture resulting from SSWI after cardiac surgery. A 50-year-old male underwent an aortic valve replacement (AVR). Three months after the valve operation, he presented with severe dyspnea, which had never before been observed, and chest computed tomography revealed an ascending aortic rupture with large hematoma compressing the main pulmonary artery. We performed an emergent operation for aortic rupture that possibly originated from the SSWI. Postoperatively, the patient died of hypovolemic shock due to recurrent aortic rupture despite efforts to resuscitate him. PMID:27499988

  5. Subacute cardiac rupture complicating myocardial infarction. A case report.

    PubMed

    Rosato, G; Santomauro, M; Stanco, G; Petillo, F; Sauro, R; Chiariello, M; Spampinato, N; Rotiroti, D

    1996-02-01

    The authors have focused this study on the emergence of subacute ventricular free wall rupture in a seventy-six-year-old patient admitted to hospital for inferior acute myocardial infarction. After six days he showed clinical signs of bradycardia and hypotension evolving to electromechanical dissociation. Given an adequate pharmacologic therapy, the patient was submitted to echocardiography, which was believed to be consistent with myocardial rupture, showing a moderate to large pericardial effusion. Pericardiocentesis of 150 mL of bloody fluid resulted in a further improvement in his hemodynamics. The patient underwent cardiac surgery with repair of the myocardial rupture through a large diaphragmatic infarction by a Dacron polyester fiber graft and pacemaker placement. In conclusion the authors confirm the relevant role of clinical data such as persistent chest pain and hemodynamic instability and the value of echocardiography in identifying subacute myocardial free wall rupture after an episode of acute myocardial infarction. PMID:8595015

  6. Acute Bilateral Traumatic Achilles Tendon Rupture – A Rare Presentation

    PubMed Central

    Jhaveri, Maulik; Golwala, Paresh; Merh, Aditya; Patel, Amit

    2016-01-01

    The Achilles tendon is the strongest tendon in the body, which is commonly ruptured in male athletes. Bilateral rupture of the Achilles tendon is a rare condition with very few reported cases in the literature. It poses a challenge in management, and hence, we report a case with traumatic bilateral Achilles tendon rupture in a young male patient and its management. One side was treated conservatively as the rupture was partial and the other side, which had a complete tear, was operated. At nine months follow-up, the patient has had a satisfactory result and is now bearing full weight without any problems. We suggest this method of treatment to be worthwhile for this unusual entity. PMID:27588227

  7. Endobronchial Cartilage Rupture: A Rare Cause of Lobar Collapse.

    PubMed

    Dasa, Osama; Siddiqui, Nauman; Ruzieh, Mohammed; Javaid, Toseef

    2016-01-01

    Endobronchial cartilage rupture is a rare clinical condition, which can present in patients with severe emphysema with sudden onset shortness of breath. We present a case of a 62-year-old male who presented to our emergency department with sudden onset shortness of breath. Chest X-ray showed lung hyperinflation and a right lung field vague small density. Chest Computed Tomography confirmed the presence of right middle lobe collapse. Bronchoscopy revealed partial right middle lobe atelectasis and an endobronchial cartilage rupture. Endobronchial cartilage rupture is a rare condition that can present as sudden onset shortness of breath due to lobar collapse in patients with emphysema and can be triggered by cough. Bronchoscopic findings include finding a collapsed lung lobe and a visible ruptured endobronchial cartilage. A high index of suspicion, chest imaging, and early bronchoscopy can aid in the diagnosis and help prevent complications. PMID:27525149

  8. Neglected bilateral rupture of the patellar tendon: A case report.

    PubMed

    Cherrad, Taoufik; Louaste, Jamal; Kasmaoui, El Houcine; Bousbaä, Hicham; Rachid, Khaled

    2015-12-01

    Simultaneous bilateral rupture of the patellar tendon (PT) is extremely rare and is generally associated to some chronic diseases. When the rupture becomes chronic, it is more difficult to repair that as it remained untreated. The diagnosis, which is clinical, is often delayed, guided by standard radiography and confirmed by ultrasound or MRI. The management of a bilateral neglected, chronic patellar tendon rupture must address some serious difficulties: the proximally retracted patella, the reconstruction of the patellar tendon, finally, the temporary protection of this repair. We report a case of neglected bilateral rupture of the patellar tendon in a chronic hemodialysis patient, treated with a plastic surgery of the ipsilateral quadriceps tendon. PMID:26566349

  9. Endobronchial Cartilage Rupture: A Rare Cause of Lobar Collapse

    PubMed Central

    Siddiqui, Nauman; Javaid, Toseef

    2016-01-01

    Endobronchial cartilage rupture is a rare clinical condition, which can present in patients with severe emphysema with sudden onset shortness of breath. We present a case of a 62-year-old male who presented to our emergency department with sudden onset shortness of breath. Chest X-ray showed lung hyperinflation and a right lung field vague small density. Chest Computed Tomography confirmed the presence of right middle lobe collapse. Bronchoscopy revealed partial right middle lobe atelectasis and an endobronchial cartilage rupture. Endobronchial cartilage rupture is a rare condition that can present as sudden onset shortness of breath due to lobar collapse in patients with emphysema and can be triggered by cough. Bronchoscopic findings include finding a collapsed lung lobe and a visible ruptured endobronchial cartilage. A high index of suspicion, chest imaging, and early bronchoscopy can aid in the diagnosis and help prevent complications. PMID:27525149

  10. CT of ruptured aneurysm of aberrant right subclavian artery.

    PubMed

    Vega, A; Ortíz, A; Longo, J M; Pagola, M A

    1987-01-01

    This paper presents the first description of a ruptured aneurysm of an aberrant right subclavian artery. CT clearly demonstrated the vascular malformation as well as the existence of a bilateral hemothorax. PMID:3102065

  11. Acute Patellar Tendon Rupture after Total Knee Arthroplasty Revision

    PubMed Central

    Rhee, Seung Joon; Pham, The Hien

    2015-01-01

    Patellar tendon rupture is a catastrophic complication following total knee arthroplasty (TKA). Though revision TKA has been suspected of being a predisposing factor for the occurrence of patellar tendon rupture, there are few reports on patellar tendon rupture after revision TKA. Here, we present a case of acute patellar tendon rupture that occurred after TKA revision. In the patient, the patellar tendon was so thin and could not be repaired, and accordingly was sutured end to end. We used the anterior tibialis tendon allograft to augment the poor quality patellar tendon tissue. Fixation of the allograft was done by using the bone tunnel created through tibial tuberosity and suturing the allograft to the patellar tendon and quadriceps tendon. The patient was instructed to wear a full extension knee splint and was kept non-weight bearing for 6 weeks after operation. Full knee extension could be achieved 6 weeks postoperatively. PMID:26060612

  12. Ultrasound Screening for Abdominal Aortic Aneurysm

    PubMed Central

    2006-01-01

    Executive Summary Objective The aim of this review was to assess the effectiveness of ultrasound screening for asymptomatic abdominal aortic aneurysm (AAA). Clinical Need Abdominal aortic aneurysm is a localized abnormal dilatation of the aorta greater than 3 cm. In community surveys, the prevalence of AAA is reported to be between 2% and 5.4%. Abdominal aortic aneurysms are found in 4% to 8% of older men and in 0.5% to 1.5% of women aged 65 years and older. Abdominal aortic aneurysms are largely asymptomatic. If left untreated, the continuing extension and thinning of the vessel wall may eventually result in rupture of the AAA. Often rupture may occur without warning, causing acute pain. Rupture is always life threatening and requires emergency surgical repair of the ruptured aorta. The risk of death from ruptured AAA is 80% to 90%. Over one-half of all deaths attributed to a ruptured aneurysm take place before the patient reaches hospital. In comparison, the rate of death in people undergoing elective surgery is 5% to 7%; however, symptoms of AAA rarely occur before rupture. Given that ultrasound can reliably visualize the aorta in 99% of the population, and its sensitivity and specificity for diagnosing AAA approaches 100%, screening for aneurysms is worth considering as it may reduce the incidence of ruptured aneurysms and hence reduce unnecessary deaths caused by AAA-attributable mortality. Review Strategy The Medical Advisory Secretariat used its standard search strategy to retrieve international health technology assessments and English-language journal articles from selected databases to determine the effectiveness of ultrasound screening for abdominal aortic aneurysms. Case reports, letters, editorials, nonsystematic reviews, non-human studies, and comments were excluded. Questions asked: Is population-based AAA screening effective in improving health outcomes in asymptomatic populations? Is AAA screening acceptable to the population? Does this affect the

  13. Milking-Like Effect as the First Clue of Left Ventricular Free Wall Rupture.

    PubMed

    Bastante, Teresa; Rivero, Fernando; Cuesta, Javier; Aguilera, María Cruz; Rodríguez, Daniel; Benedicto, Amparo; Alfonso, Fernando

    2016-08-01

    Left ventricular free wall rupture (FWR) is a rare but dreadful complication after acute myocardial infarction (AMI). A coronary "milking-like" effect has been previously related to ventricular pseudoaneurysm or true aneurysm but not yet with other mechanical complications such as left ventricular FWR. We describe 2 patients with AMI showing a coronary milking-like effect in the infarct-related artery at the time of primary percutaneous coronary intervention. Left ventricular FWR eventually developed and the patients died. We propose that a coronary milking-like effect in the infarct-related artery is a marker of patients at high risk for this life-threatening mechanical complication. PMID:27084073

  14. Association of Oversized Tracheal Tubes and Cuff Overinsufflation With Postintubation Tracheal Ruptures

    PubMed Central

    Sudhoff, Tobias H.; Seidl, Rainer O.; Estel, Barbara

    2015-01-01

    Objectives Postintubation tracheal ruptures (PTR) are rare but cause severe complications. Our objective was to investigate the tracheal pattern of injury resulting from cuff inflation of the tracheal tube, to study the two main factors responsible for PTR (cuff overinsufflation and inapplicable tube sizes), and to explain the context, why small women are particularly susceptible to PTR. Methods Experimental study performed on 28 fresh human laryngotracheal specimens (16 males, 12 females) within 24 hours post autopsy. Artificial ventilation was simulated by using an underwater construction and a standard tracheal tube. Tube sizes were selected according to our previously published nomogram. Tracheal lesions were detected visually and tracheal diameters measured. The influence of body size, sex difference and appropriate tube size were investigated according to patient height. Results In all 28 cases, the typical tracheal lesion pattern was a longitudinal median rupture of the posterior trachea. Appropriate tube sizes according to body size caused PTR with significantly higher cuff pressure when compared with oversized tubes. An increased risk of PTR was found in shorter patients, when oversized tubes were used. Sex difference did not have any significant influence. Conclusion This experimental model provides information about tracheal patterns in PTR for the first time. The model confirms by experiment the observations of case series in PTR patients, and therefore emphasizes the importance of correct tube size selection according to patient height. This minimizes the risk of PTR, especially in shorter patients, who have an increased risk of PTR when oversized tubes are used. PMID:26622963

  15. Retrograde approach for closure of ruptured sinus of Valsalva.

    PubMed

    Jayaranganath, M; Subramanian, Anand; Manjunath, Cholenahally Nanjappa

    2010-07-01

    Though ruptured sinuses of Valsalva have been traditionally managed surgically, they are amenable to transcatheter closure. Various devices have been used for closure of these defects. We describe a novel technique of closure of a ruptured right sinus of Valsalva into the right ventricular outflow tract. A muscular ventricular septal defect occluder was deployed retrogradely, without resorting to the usual antegrade technique involving formation of an arteriovenous loop. PMID:20603510

  16. A support-operator method for 3-D rupture dynamics

    NASA Astrophysics Data System (ADS)

    Ely, Geoffrey P.; Day, Steven M.; Minster, Jean-Bernard

    2009-06-01

    We present a numerical method to simulate spontaneous shear crack propagation within a heterogeneous, 3-D, viscoelastic medium. Wave motions are computed on a logically rectangular hexahedral mesh, using the generalized finite-difference method of Support Operators (SOM). This approach enables modelling of non-planar surfaces and non-planar fault ruptures. Our implementation, the Support Operator Rupture Dynamics (SORD) code, is highly scalable, enabling large-scale, multiprocessors calculations. The fault surface is modelled by coupled double nodes, where rupture occurs as dictated by the local stress conditions and a frictional failure law. The method successfully performs test problems developed for the Southern California Earthquake Center (SCEC)/U.S. Geological Survey (USGS) dynamic earthquake rupture code validation exercise, showing good agreement with semi-analytical boundary integral method results. We undertake further dynamic rupture tests to quantify numerical errors introduced by shear deformations to the hexahedral mesh. We generate a family of meshes distorted by simple shearing, in the along-strike direction, up to a maximum of 73°. For SCEC/USGS validation problem number 3, grid-induced errors increase with mesh shear angle, with the logarithm of error approximately proportional to angle over the range tested. At 73°, rms misfits are about 10 per cent for peak slip rate, and 0.5 per cent for both rupture time and total slip, indicating that the method (which, up to now, we have applied mainly to near-vertical strike-slip faulting) is also capable of handling geometries appropriate to low-angle surface-rupturing thrust earthquakes. Additionally, we demonstrate non-planar rupture effects, by modifying the test geometry to include, respectively, cylindrical curvature and sharp kinks.

  17. First report of splenic rupture following deep enteroscopy.

    PubMed

    Girelli, Carlo Maria; Pometta, Roberta; Facciotto, Corinna; Mella, Roberto; Bernasconi, Giordano

    2016-05-10

    Splenic rupture is a rare complication of diagnostic and therapeutic gastrointestinal endoscopy procedures. Herein, we report for the first time a case of splenic rupture following therapeutic retrograde double-balloon enteroscopy, which occurred in an 85-year-old man who was treated for recurrent mid-intestinal bleeding that resulted from ileal angioectasia. This patient promptly underwent an operation and eventually recovered. PMID:27170840

  18. First report of splenic rupture following deep enteroscopy

    PubMed Central

    Girelli, Carlo Maria; Pometta, Roberta; Facciotto, Corinna; Mella, Roberto; Bernasconi, Giordano

    2016-01-01

    Splenic rupture is a rare complication of diagnostic and therapeutic gastrointestinal endoscopy procedures. Herein, we report for the first time a case of splenic rupture following therapeutic retrograde double-balloon enteroscopy, which occurred in an 85-year-old man who was treated for recurrent mid-intestinal bleeding that resulted from ileal angioectasia. This patient promptly underwent an operation and eventually recovered. PMID:27170840

  19. Traumatic rupture of arachnoid cyst with subdural hygroma.

    PubMed

    Rajesh, A; Bramhaprasad, V; Purohit, A K

    2012-01-01

    Intracranial arachnoid cysts developing in relation to the cerebral hemispheres and middle cranial fossa are usually incidental or asymptomatic. However, most of the clinically active cysts present with seizures because of chronic compression. Presentation as raised intracranial pressure due to cyst rupture into the subdural space is a rare clinical entity. We herein present a case of an asymptomatic arachnoid cyst with rupture into the subdural space bilaterally and presenting as raised intracranial pressure. PMID:22837775

  20. A Tuboovarian Abscess Associated with a Ruptured Spleen

    PubMed Central

    Li, Jennifer S.; Sheele, Johnathan Michael

    2016-01-01

    We report the first case of a tuboovarian abscess complicated by a ruptured spleen. Our patient was a 27-year-old female with human immunodeficiency virus (HIV) who presented to the emergency department (ED) with complaints of urinary symptoms and diarrhea. After being diagnosed with a tuboovarian abscess (TOA), she received antibiotics and was admitted to the gynecology service. Shortly thereafter she developed hemorrhagic shock, necessitating a splenectomy and salpingooophorectomy from a ruptured spleen. PMID:26904315