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Sample records for necrosis causing failure

  1. Radiation necrosis causing failure of automatic ventilation during sleep with central sleep apnea

    International Nuclear Information System (INIS)

    Udwadia, Z.F.; Athale, S.; Misra, V.P.; Wadia, N.H.

    1987-01-01

    A patient operated upon for a midline cerebellar hemangioblastoma developed failure of automatic respiration during sleep, together with central sleep apnea syndrome, approximately two years after receiving radiation therapy to the brain. Clinical and CT scan findings were compatible with a diagnosis of radiation necrosis as the cause of his abnormal respiratory control

  2. Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure

    Directory of Open Access Journals (Sweden)

    Honglei eWeng

    2015-06-01

    Full Text Available Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called second pathway of liver regeneration. The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

  3. Two sides of one coin: massive hepatic necrosis and progenitor cell-mediated regeneration in acute liver failure.

    Science.gov (United States)

    Weng, Hong-Lei; Cai, Xiaobo; Yuan, Xiaodong; Liebe, Roman; Dooley, Steven; Li, Hai; Wang, Tai-Ling

    2015-01-01

    Massive hepatic necrosis is a key event underlying acute liver failure, a serious clinical syndrome with high mortality. Massive hepatic necrosis in acute liver failure has unique pathophysiological characteristics including extremely rapid parenchymal cell death and removal. On the other hand, massive necrosis rapidly induces the activation of liver progenitor cells, the so-called "second pathway of liver regeneration." The final clinical outcome of acute liver failure depends on whether liver progenitor cell-mediated regeneration can efficiently restore parenchymal mass and function within a short time. This review summarizes the current knowledge regarding massive hepatic necrosis and liver progenitor cell-mediated regeneration in patients with acute liver failure, the two sides of one coin.

  4. Acute renal failure caused by Klebsiella pneumoniae pyelonephritis

    NARCIS (Netherlands)

    Creyghton, W. M.; Lobatto, S.; Weening, J. J.

    2001-01-01

    We report a 34-year-old male patient without prior medical history who presented with acute renal failure due to acute bacterial pyelonephritis. Both blood and urine cultures grew Klebsiella pneumoniae. Although a kidney biopsy revealed extensive necrosis and no viable glomeruli, renal function

  5. Trigger wrist caused by avascular necrosis of the capitate: a case report.

    Science.gov (United States)

    Matsui, Yuichiro; Kawamura, Daisuke; Kida, Hiroaki; Hatanaka, Kanako C; Iwasaki, Norimasa

    2018-03-27

    Trigger wrist is a rare condition first described by Marti in 1960, and various causes have been reported. The condition mostly occurs with finger flexion and extension, and rarely with flexion and extension of the wrist itself. Avascular necrosis of the capitate is also a rare condition, first described by Jönsson in 1942. While some reports of this condition have been published, little is known about its etiology. Therefore, no established treatment exists. We report a case of trigger wrist caused by avascular necrosis of the capitate. A 16-year-old right-handed male who was a high school handball player was referred to our department from a nearby hospital 5 months after the onset of pain in the dorsal aspect of the right wrist, with an unknown cause. At the previous hospital, imaging findings led to a diagnosis of avascular necrosis of the capitate, and conservative treatment with a wrist brace did not improve the pain. At the initial visit to our department, the patient was noted to have a painful trigger wrist that was brought on by wrist flexion and extension. Preoperative imaging findings led to a diagnosis of trigger wrist caused by capitolunate instability secondary to avascular necrosis of the capitate. We performed a partial excision of the proximal capitate with tendon ball interposition. Two years after surgery, the patient's clinical outcome was favorable, with no recurrence of wrist pain or triggering. Both trigger wrist and avascular necrosis of the capitate are rare disorders. When a patient presents with painful triggering at the wrist, surgeons must bear in mind that avascular necrosis of the capitate may result in this phenomenon. We recommend partial excision of the proximal capitate with tendon ball interposition for the treatment of this lesion.

  6. The diagnostic value of contrast-enhanced CT in Acute bilateral renal cortical necrosis: a case report

    International Nuclear Information System (INIS)

    Choi, Pil Youb; Lee, Su Han; Lee, Woo Dong

    1996-01-01

    Acute renal cortical necrosis in which there is destruction of the renal cortex and sparing of the renal medulla, is a relatively rare cause of acute renal failure. A definitive diagnosis of acute renal cortical necrosis is based on renal biopsy, but on CT(computed tomography) the rather specific contrast-enhanced appearance of acute renal cortical necrosis has been described. As renal biopsy is not available, contrast-enhanced CT is a useful, noninvasive investigate modality for the early diagnosis of acute renal cortical necrosis. We report the characteristic CT findings of acute renal cortical necrosis in a patient with acute renal failure following an operation for abdominal trauma

  7. A Rare Cause of Acute Abdomen: Idiopathic Isolated Cecal Necrosis

    Directory of Open Access Journals (Sweden)

    Ender Özer

    2015-03-01

    Full Text Available Idiopathic isolated cecal necrosis is a clinical problem characterized by right-sided inferior abdominal pain. It is rarely seen, develops due to decreased blood flow to the colon and, imitates acute appendicitis. Its clinical signs are similar to many illnesses causing sensitivity in the right inferior quadrant and, the diagnosis is generally determined during surgery. An 86-year-old male patient presented with the complaints of abdominal pain, trichiniasis, nausea and vomiting. Surgical intervention was decided when physical examination and laboratory results were taken into consideration. After diagnostic laparoscopy, right hemicolectomy was performed because of cecal necrosis. While the mortality and morbidity rates for ischemic bowel disease are high, prognosis for early diagnosed patients with isolated cecal necrosis is better, provided that timely surgical treatment is decided.

  8. Electrical failure analysis for root-cause determination

    International Nuclear Information System (INIS)

    Riddle, J.

    1990-01-01

    This paper outlines a practical failure analysis sequence. Several technical definitions are required. A failure is defined as a component that was operating in a system where the system malfunctioned and the replacement of the device restored system functionality. The failure mode is the malfunctioning behavior of the device. The failure mechanism is the underlying cause or source of the failure mode. The failure mechanism is the root cause of the failure mode. The failure analysis procedure needs to be adequately refined to result in the determination of the cause of failure to the degree that corrective action or design changes will prevent recurrence of the failure mode or mechanism. An example of a root-cause determination analysis performed for a nuclear power industry customer serves to illustrate the analysis methodology

  9. Governing of common cause failures

    International Nuclear Information System (INIS)

    Bock, H.W.

    1998-01-01

    Agreed strategy is to govern common cause failures by the application of diversity, to assure that the overall plant safety objectives are met even in the case that a common cause failure of a system with all redundant trains is assumed. The presented strategy aims on the application of functional diversity without the implementation of equipment diversity. In the focus are the design criteria which have to be met for the design of independent systems in such a way that the time-correlated failure of such independent systems according a common cause can be excluded deterministically. (author)

  10. Common cause failures of reactor pressure components

    International Nuclear Information System (INIS)

    Mankamo, T.

    1978-01-01

    The common cause failure is defined as a multiple failure event due to a common cause. The existence of common failure causes may ruin the potential advantages of applying redundancy for reliability improvement. Examples relevant to large mechanical components are presented. Preventive measures against common cause failures, such as physical separation, equipment diversity, quality assurance, and feedback from experience are discussed. Despite the large number of potential interdependencies, the analysis of common cause failures can be done within the framework of conventional reliability analysis, utilizing, for example, the method of deriving minimal cut sets from a system fault tree. Tools for the description and evaluation of dependencies between components are discussed: these include the model of conditional failure causes that are common to many components, and evaluation of the reliability of redundant components subjected to a common load. (author)

  11. Acute renal failure in pregnancy, its causes and outcome, 1 year study at sheikh zayed hospital lahore

    International Nuclear Information System (INIS)

    Rashid, H.; Akram, M.

    2013-01-01

    Objective: The objective of this study was to deter-mine the frequency, etiology, clinical course and out-come of pregnancy related acute renal failure. Type of Study: Observational and prospective hospital based study. Place of Study: Department of Nephrology, Shaikh Zayed Hospital Lahore. Duration of Study: One year from November 2010 - October 2011. Patients and Methods: Total 210 patients of Acute renal failure (ARF) were admitted with 92 (44%) males and 118 (56%) females during this period of which 40 (19%) females were pregnancy related ARF that were included in this study. A Predesigned proforma was used. The clinical history and physical examination was carried out. Relevant laboratory tests were performed. Renal biopsy was done in few cases. The final outcome was recorded. Twenty four (24) patients were from rural community of Punjab province and remaining (16) were from urban areas. Results: Pregnancy related ARF occurred in forty (40) patients. Twenty two (55%) were multipara and 18 (45%) were primigravida. Their age was between 29 +- 4.5 years. Majority 32 (80%) patients had not received any antenatal care as compared to 8 (20%) patients who had adequate antenatal care. Twelve cases (15%) presented in their first and second trimester of pregnancy while 28 (70%) patients developed ARF in their third trimester or the puerperium. Twenty four (60%) patients were anuric. Antepartum haemorrhage (APH) in 2 (5%) cases, postpartum haemorrhage (PPH) in 6 (15%) cases, Septic abortion in 6 (15%), puerperal sepsis in 8 (20%) and DIC in 4 (10%) cases, Intra-uterine fetal death (IUD) in 12 (30%) and HELLPS in 2 (5%) cases. Sepsis was the commonest cause of ARF. Thirty four (85%) patients received hemodialysis and 6 (15%) did not require any dialysis. Commonest clinical diagnosis was acute tubular necrosis (ATN). Complete recovery was seen in 8 (20%) cases .Acute renal cortical necrosis was seen in 14 (35%) cases and 18 (45%) patients had patchy cortical necrosis

  12. Common cause failure analysis methodology for complex systems

    International Nuclear Information System (INIS)

    Wagner, D.P.; Cate, C.L.; Fussell, J.B.

    1977-01-01

    Common cause failure analysis, also called common mode failure analysis, is an integral part of a complex system reliability analysis. This paper extends existing methods of computer aided common cause failure analysis by allowing analysis of the complex systems often encountered in practice. The methods presented here aid in identifying potential common cause failures and also address quantitative common cause failure analysis

  13. Structures for common-cause failure analysis

    International Nuclear Information System (INIS)

    Vaurio, J.K.

    1981-01-01

    Common-cause failure methodology and terminology have been reviewed and structured to provide a systematical basis for addressing and developing models and methods for quantification. The structure is based on (1) a specific set of definitions, (2) categories based on the way faults are attributable to a common cause, and (3) classes based on the time of entry and the time of elimination of the faults. The failure events are then characterized by their likelihood or frequency and the average residence time. The structure provides a basis for selecting computational models, collecting and evaluating data and assessing the importance of various failure types, and for developing effective defences against common-cause failure. The relationships of this and several other structures are described

  14. Importance analysis for the systems with common cause failures

    International Nuclear Information System (INIS)

    Pan Zhijie; Nonaka, Yasuo

    1995-01-01

    This paper extends the importance analysis technique to the research field of common cause failures to evaluate the structure importance, probability importance, and β-importance for the systems with common cause failures. These importance measures would help reliability analysts to limit the common cause failure analysis framework and find efficient defence strategies against common cause failures

  15. A huge bladder calculus causing acute renal failure.

    Science.gov (United States)

    Komeya, Mitsuru; Sahoda, Tamami; Sugiura, Shinpei; Sawada, Takuto; Kitami, Kazuo

    2013-02-01

    A 81-year-old male was referred to our emergency outpatient unit due to acute renal failure. The level of serum creatinine was 276 μmol/l. A CT scan showed bilateral hydronephroureter, large bladder stone (7 cm × 6 cm × 6 cm) and bladder wall thickness. He was diagnosed as post renal failure due to bilateral hydronephroureter. Large bladder stone is thought to be the cause of bilateral hydronephroureter and renal failure. To improve renal failure, we performed open cystolithotomy and urethral catheterization. Three days after the surgery, the level of serum creatinine decreased to 224 μmol/l. He was discharged from our hospital with uneventful course. Bladder calculus is thought to be a rare cause of renal failure. We summarize the characteristics of bladder calculus causing renal failure. We should keep that long-term pyuria and urinary symptom, and repeated urinary tract infection can cause huge bladder calculus and renal failure in mind.

  16. Common-Cause Failure Analysis in Event Assessment

    International Nuclear Information System (INIS)

    Rasmuson, D.M.; Kelly, D.L.

    2008-01-01

    This paper reviews the basic concepts of modeling common-cause failures (CCFs) in reliability and risk studies and then applies these concepts to the treatment of CCF in event assessment. The cases of a failed component (with and without shared CCF potential) and a component being unavailable due to preventive maintenance or testing are addressed. The treatment of two related failure modes (e.g. failure to start and failure to run) is a new feature of this paper, as is the treatment of asymmetry within a common-cause component group

  17. Data needs for common cause failure analysis

    International Nuclear Information System (INIS)

    Parry, G.W.; Paula, H.M.; Rasmuson, D.; Whitehead, D.

    1990-01-01

    The procedures guide for common cause failure analysis published jointly by USNRC and EPRI requires a detailed historical event analysis. Recent work on the further development of the cause-defense picture of common cause failures introduced in that guide identified the information that is necessary to perform the detailed analysis in an objective manner. This paper summarizes these information needs

  18. Antiretroviral Drug as a Cause of Bilateral Avascular Necrosis of the ...

    African Journals Online (AJOL)

    Background: Avascular necrosis (AVN) is one of the most dreadful disease conditions of the hip which may be very difficult to treat if not detected early. Protease inhibitor is useful in combined antiretroviral therapy but now being reported as one of the causes of AVN. In this case report, we present a case of bilateral ...

  19. Partial pulp necrosis caused by excessive orthodontic force

    Directory of Open Access Journals (Sweden)

    Min-Young Kim

    2011-03-01

    Full Text Available As the dental pulp is encased with a rigid, noncompliant shell, changes in pulpal blood flow or vascular tissue pressure can have serious implication for the health of pulp. Numerous studies have demonstrated that orthodontic force application may influence both blood flow and cellular metabolism, leading degenerative and/or inflammatory responses in the dental pulp. The aim of this case report is to present a case about tooth with chronic periapical abscess which showed normal vital responses. Excessive orthodontic force is thought to be the prime cause of partial pulp necrosis. Owing to remaining vital tissue, wrong dianosis can be made, and tooth falsely diagnosed as vital may be left untreated, causing the necrotic tissue to destroy the supporting tissuses. Clinician should be able to utilize various diagnostic tools for the precise diagnosis, and be aware of the endodontic-orthodontic inter-relationship.

  20. Root cause of failure analysis and the system engineer

    International Nuclear Information System (INIS)

    Coppock, M.S.; Hartwig, A.W.

    1990-01-01

    In an industry where ever-increasing emphasis is being placed on root cause of failure determination, it is imperative that a successful nuclear utility have an effective means of identifying failures and performing the necessary analyses. The current Institute of Nuclear Power Operations (INPO) good practice, OE-907, root-cause analysis, gives references to methodology that will help determine breakdowns in procedures, programs, or design but gives very little guidance on how or when to perform component root cause of failure analyses. The system engineers of nuclear utilities are considered the focal point for their respective systems and are required by most programs to investigate component failures. The problem that the system engineer faces in determining a component root cause of failures lies in acquisition of the necessary data to identify the need to perform the analysis and in having the techniques and equipment available to perform it. The system engineers at the Palo Verde nuclear generating station routinely perform detailed component root cause of failure analyses. The Palo Verde program provides the system engineers with the information necessary to identify when a component root cause of failure is required. Palo Verde also has the necessary equipment on-site to perform the analyses

  1. Extension of myocardial necrosis differently affects MIBG retention in heart failure caused by ischaemic heart disease or by dilated cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Marini, Cecilia; Giorgetti, Assuero; Gimelli, Alessia; Kusch, Annette; Sereni, Nadia; Marzullo, Paolo; Sambuceti, Gianmario [CNR Institute of Clinical Physiology, Pisa (Italy); L' Abbate, Antonio [Scuola Superiore di Studi Universitari Sant' Anna, Pisa (Italy)

    2005-06-01

    This study aims to investigate the relationship between cardiac sympathetic nervous function (CSNF) and myocardial perfusion/function in patients with heart failure (HF) due to dilated cardiomyopathy (DCM) or ischaemic heart disease (CAD). Twenty patients (10 DCM, 10 CAD, 17 males, age 69{+-}5 years) with NYHA class IIIb HF were studied. CSNF was evaluated by early/delayed {sup 123}I-metaiodobenzylguanidine (MIBG) uptake and regional washout (WO). Myocardial perfusion and function were evaluated by {sup 99m}Tc-tetrofosmin gated single-photon emission tomography (G-SPECT) using a 20-segment model for 400 segments. In each segment, regional MIBG WO was computed as (count density in early images-count density in delayed images/count density in early images) x 100. DCM and CAD showed similar summed rest perfusion score (6.7{+-}5 vs 9.5{+-}5, p=NS) and mean ejection fraction values (29{+-}7% vs 30{+-}9%, p=NS). By contrast, the summed thickening score was higher in DCM than in CAD patients (26{+-}7 vs 17{+-}6, p<0.05). QGS analysis identified akinesis/dyskinesis in 129/137 (94%) severely hypoperfused segments which were considered as damaged. According to the underlying aetiology of HF, marked differences in regional MIBG WO were observed. In fact, within the CAD group, regional MIBG WO was lower in reference than in damaged segments (38{+-}21% vs 46{+-}19%, p<0.05). By contrast, in DCM patients, regional MIBG WO was faster in reference than in damaged segments (49{+-}18% vs 41{+-}30%, p<0.05). When the two groups were directly compared, regional MIBG WO from damaged areas was similar irrespective of the underlying disease, while it was faster in DCM than in CAD patients from reference segments. These data confirm the hypothesis that the presence of myocardial necrosis in HF due to CAD and the consequent loss of neuronal endings cause alterations in regional MIBG WO different from those observed in DCM. (orig.)

  2. Tumor Necrosis Factor Inhibitor Primary Failure Predicts Decreased Ustekinumab Efficacy in Psoriasis Patients.

    Science.gov (United States)

    Sorensen, Eric P; Fanucci, Kristina A; Saraiya, Ami; Volf, Eva; Au, Shiu-chung; Argobi, Yahya; Mansfield, Ryan; Gottlieb, Alice B

    2015-08-01

    Additional studies are needed to examine the efficacy of ustekinumab in psoriasis patients who have previously been exposed to tumor necrosis factor inhibitors (TNFi). To examine the predictive effect of TNFi primary failure and the number of TNFi exposures on the efficacy of ustekinumab in psoriasis treatment. This retrospective study examined 44 psoriasis patients treated at the Tufts Medical Center Department of Dermatology between January 2008 and July 2014. Patients were selected if they were treated with ustekinumab and had ≥ 1 previous TNFi exposure. The following subgroups were compared: patients with vs without a previous TNFi primary failure, and patients with one vs multiple previous TNFi exposures. The efficacy measure used was the previously validated Simple Measure for Assessing Psoriasis Activity (S-MAPA), which is calculated by the product of the body surface area and physician global assessment. The primary outcome was the percentage improvement S-MAPA from course baseline at week 12 of ustekinumab treatment. Secondary outcomes were the psoriasis clearance, primary failure, and secondary failure rates with ustekinumab treatment. Patients with a previous TNFi primary failure had a significantly lower percentage improvement in S-MAPA score at week 12 of ustekinumab treatment compared with patients without TNFi primary failure (36.2% vs 61.1%, P=.027). Multivariate analysis demonstrated that this relationship was independent of patient demographics and medical comorbidities. Patients with multiple TNFi exposures had a non-statistically significant lower percentage S-MAPA improvement at week 12 (40.5% vs 52.9%, P=.294) of ustekinumab treatment compared with patients with a single TNFi exposure. Among psoriasis patients previously exposed to TNFi, a history of a previous TNFi primary failure predicts a decreased response to ustekinumab independent of patient demographics and medical comorbidities.

  3. BACFIRE, Minimal Cut Sets Common Cause Failure Fault Tree Analysis

    International Nuclear Information System (INIS)

    Fussell, J.B.

    1983-01-01

    1 - Description of problem or function: BACFIRE, designed to aid in common cause failure analysis, searches among the basic events of a minimal cut set of the system logic model for common potential causes of failure. The potential cause of failure is called a qualitative failure characteristics. The algorithm searches qualitative failure characteristics (that are part of the program input) of the basic events contained in a set to find those characteristics common to all basic events. This search is repeated for all cut sets input to the program. Common cause failure analysis is thereby performed without inclusion of secondary failure in the system logic model. By using BACFIRE, a common cause failure analysis can be added to an existing system safety and reliability analysis. 2 - Method of solution: BACFIRE searches the qualitative failure characteristics of the basic events contained in the fault tree minimal cut set to find those characteristics common to all basic events by either of two criteria. The first criterion can be met if all the basic events in a minimal cut set are associated by a condition which alone may increase the probability of multiple component malfunction. The second criterion is met if all the basic events in a minimal cut set are susceptible to the same secondary failure cause and are located in the same domain for that cause of secondary failure. 3 - Restrictions on the complexity of the problem - Maxima of: 1001 secondary failure maps, 101 basic events, 10 cut sets

  4. Coordination failure caused by sunspots

    DEFF Research Database (Denmark)

    Beugnot, Julie; Gürgüç, Zeynep; Øvlisen, Frederik Roose

    2012-01-01

    on the efficient equilibrium, we consider sunspots as a potential reason for coordination failure. We conduct an experiment with a three player 2x2x2 game in which coordination on the efficient equilibrium is easy and should normally occur. In the control session, we find almost perfect coordination on the payoff......-dominant equilibrium, but in the sunspot treatment, dis-coordination is frequent. Sunspots lead to significant inefficiency, and we conclude that sunspots can indeed cause coordination failure....

  5. Acute Liver Failure from Tumor Necrosis Factor-α Antagonists: Report of Four Cases and Literature Review.

    Science.gov (United States)

    Kok, Beverley; Lester, Erica L W; Lee, William M; Hanje, A James; Stravitz, R Todd; Girgis, Safwat; Patel, Vaishali; Peck, Joshua R; Esber, Christopher; Karvellas, Constantine J

    2018-03-21

    Tumor necrosis factor-α antagonists (anti-TNF-α) have been associated with drug-induced liver injury. However, cases of anti-TNF-α-associated acute liver failure have only been rarely reported. To identify cases of anti-TNF-α-associated acute liver failure and evaluate patterns of liver injury and common characteristics to the cases. The United States Acute Liver Failure Study Group database was searched from 1998 to 2014. Four subjects were identified. A PubMed search for articles that reported anti-TNF-α-associated acute liver failure identified five additional cases. The majority of individuals affected were female (eight of nine cases). Age of individual ranged from 20 to 53 years. The most common anti-TNF-α agent associated with acute liver failure was infliximab (n = 8). The latency between initial drug exposure and acute liver failure ranged from 3 days to over a year. Of the nine cases, six required emergency LT. Liver biopsy was obtained in seven cases with a preponderance toward cholestatic-hepatitic features; none showed clear autoimmune features. Anti-TNF-α-associated acute liver failure displays somewhat different characteristics compared with anti-TNF-α-induced drug-induced liver injury. Infliximab was implicated in the majority of cases. Cholestatic-hepatitic features were frequently found on pre-transplant and explant histology.

  6. Seismically induced common cause failures in PSA of nuclear power plants

    International Nuclear Information System (INIS)

    Ravindra, M.K.; Johnson, J.J.

    1991-01-01

    In this paper, a research project on the seismically induced common cause failures in nuclear power plants performed for Toshiba Corp. is described. The objective of this research was to develop the procedure for estimating the common cause failure probabilities of different nuclear power plant components using the combination of seismic experience data, the review of sources of dependency, sensitivity studies and engineering judgement. The research project consisted of three tasks: the investigation of damage instances in past earthquakes, the analysis of multiple failures and their root causes, and the development of the methodology for assessing seismically induced common cause failures. The details of these tasks are explained. In this paper, the works carried out in the third task are described. A methodology for treating common cause failures and the correlation between component failures is formulated; it highlights the modeling of event trees taking into account common cause failures and the development of fault trees considering the correlation between component failures. The overview of seismic PSA, the quantification methods for dependent failures and Latin Hypercube sampling method are described. (K.I.)

  7. Investigations of inter-system common cause failures

    International Nuclear Information System (INIS)

    Nonclerca, P.; Gallois, M.; Vasseur, D.

    2012-01-01

    Intra-system common-cause failures (CCF) are widely studied and addressed in existing PSA models, but the information and studies that incorporate the potential for inter-system CCF is limited. However, the French Safety Authority has requested that EDF investigate the possibility of common-cause failure across system boundaries for Flamanville 3 (an EPR design). Also, the modeling of inter-system CCF, or the proof that their impact is negligible, would satisfy Capability Category III for one of the requirements in the ASME/ANS PRA standard in the U.S. EDF and EPRI have been working on a method to assess when it is necessary to take into account inter-system CCF in a PSA model between 2008 and 2010. This method is based both on the likelihood of inter-system CCF and on its demonstrated potential impact on CDF (core damage frequency). This method was first applied on pumps in different systems of the 900 MWe series plants. The second application concerned the motor-operated valves across different systems, using the same PSA model. This second application helped us refine the method, which was not optimal when the number of concerned components is very large. Since then, the method has been successfully applied on the pumps and 10 kV breakers of the EPR power plant in Flamanville. This paper describes the method and the results obtained in some of these studies. All studies have shown either that components in different systems, when they were not already part of a common cause failure group in the model, are not susceptible to common causes of failure, or that the potential for inter-system common-cause failure is negligible regarding the overall risk. (authors)

  8. Facial fat necrosis following autologous fat transfer and its management

    Directory of Open Access Journals (Sweden)

    Sweta Rai

    2014-01-01

    Full Text Available Autologous fat transfer (AFT is an increasingly popular cosmetic procedure practiced by dermatologic surgeons worldwide. As this is an office based procedure performed under local or tumescent anaesthesia with fat transferred within the same individual and limited associated down time its is considered relatively safe and risk free in the cosmetic surgery arena. We describe a case of AFT related fat necrosis causing significant facial dysmorphia and psychosocial distress. We also discuss the benefits and risks of AFT highlighting common causes of fat graft failure.

  9. Nuclear medicine in acute and chronic renal failure

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, R.A.; Byun, K.J.

    1982-07-01

    The diagnostic value of renal scintiscans in patients with acute or chronic renal failure has not been emphasized other than for the estimation of renal size. /sup 131/I OIH, /sup 67/gallium, /sup 99m/TcDTPA, glucoheptonate and DMSA all may be valuable in a variety of specific settings. Acute renal failure due to acute tubular necrosis, hepatorenal syndrome, acute interstitial nephritis, cortical necrosis, renal artery embolism, or acute pyelonephritis may be recognized. Data useful in the diagnosis and management of the patient with obstructive or reflux nephropathy may be obtained. Radionuclide studies in patients with chronic renal failure may help make apparent such causes as renal artery stenosis, chronic pyelonephritis or lymphomatous kidney infiltration. Future correlation of scanning results with renal pathology promises to further expand nuclear medicine's utility in the noninvasive diagnosis of renal disease.

  10. Nuclear medicine in acute and chronic renal failure

    International Nuclear Information System (INIS)

    Sherman, R.A.; Byun, K.J.

    1982-01-01

    The diagnostic value of renal scintiscans in patients with acute or chronic renal failure has not been emphasized other than for the estimation of renal size. 131 I OIH, 67 gallium, /sup 99m/TcDTPA, glucoheptonate and DMSA all may be valuable in a variety of specific settings. Acute renal failure due to acute tubular necrosis, hepatorenal syndrome, acute interstitial nephritis, cortical necrosis, renal artery embolism, or acute pyelonephritis may be recognized. Data useful in the diagnosis and management of the patient with obstructive or reflux nephropathy may be obtained. Radionuclide studies in patients with chronic renal failure may help make apparent such causes as renal artery stenosis, chronic pyelonephritis or lymphomatous kidney infiltration. Future correlation of scanning results with renal pathology promises to further expand nuclear medicine's utility in the noninvasive diagnosis of renal disease

  11. A new method for explicit modelling of single failure event within different common cause failure groups

    International Nuclear Information System (INIS)

    Kančev, Duško; Čepin, Marko

    2012-01-01

    Redundancy and diversity are the main principles of the safety systems in the nuclear industry. Implementation of safety components redundancy has been acknowledged as an effective approach for assuring high levels of system reliability. The existence of redundant components, identical in most of the cases, implicates a probability of their simultaneous failure due to a shared cause—a common cause failure. This paper presents a new method for explicit modelling of single component failure event within multiple common cause failure groups simultaneously. The method is based on a modification of the frequently utilised Beta Factor parametric model. The motivation for development of this method lays in the fact that one of the most widespread softwares for fault tree and event tree modelling as part of the probabilistic safety assessment does not comprise the option for simultaneous assignment of single failure event to multiple common cause failure groups. In that sense, the proposed method can be seen as an advantage of the explicit modelling of common cause failures. A standard standby safety system is selected as a case study for application and study of the proposed methodology. The results and insights implicate improved, more transparent and more comprehensive models within probabilistic safety assessment.

  12. Choice of therapeutic tactics after failure of the first tumor necrosis factor-α inhibitor

    Directory of Open Access Journals (Sweden)

    N. V. Chichasova

    2017-01-01

    Full Text Available The paper discusses whether the effect of different biological agents (BAs can be achieved in patients with active rheumatoid arthritis (RA when they inadequately respond to therapy with tumor necrosis factor-α (TNF-α inhibitors. It gives data on the efficacy of BAs with another mechanism of action (abatacept, tocilizumab, and rituximab and on the comparable efficacy of golimumab (GLM in this group of patients. It is shown that the effect of GLM therapy does not depend on the reasons for discontinuation of a previously used TNF-α inhibitors (inefficacy, adverse events, etc.. It is conclusion that GLM is effective after failure of one or two TNF-α inhibitors.

  13. Serial MR observation of cortical laminar necrosis caused by brain infarction

    Energy Technology Data Exchange (ETDEWEB)

    Komiyama, M.; Nakajima, H.; Nishikawa, M.; Yasui, T. [Department of Neurosurgery, Osaka City General Hospital (Japan)

    1998-12-01

    To examine the chronological changes characteristic of cortical laminar necrosis caused by brain infarction, 16 patients were repeatedly examined using T1-, T2-weighted spin-echo, T2{sup *}-weighted gradient echo, fluid attenuated inversion recovery (FLAIR) images, and contrast enhanced T1-weighted images at 1.0 or 1.5 T. High intensity cortical lesions were visible on the T1-weighted images from 2 weeks after ictus and became prominent at 1 to 3 months, then became less apparent, but occasionally remained at high intensity for 2 years. High intensity cortical lesions on FLAIR images became prominent from 1 month, and then became less prominent from 1 year, but occasionally remained at high intensity for 2 years. Subcortical lesions did not display high intensity on T1-weighted images at any stage. On FLAIR images, subcortical lesions initially showed slightly high intensity and then low intensity from 6 months due to encephalomalacia. Cortical lesions showed prominent contrast enhancement from 2 weeks to 3 months, but subcortical lesions were prominent from 2 weeks only up to 1 month. T2*-weighted images disclosed haemosiderin in 3 of 7 patients, but there was no correlation with cortical short T1 lesions. Cortical laminar necrosis showed characteristic chronological signal changes on T1-weighted images and FLAIR images. Cortical short T1 lesions were found not to be caused by haemorrhagic infarction. (orig.) With 5 figs., 1 tab., 9 refs.

  14. Short term effects of milrinone on biomarkers of necrosis, apoptosis, and inflammation in patients with severe heart failure

    Science.gov (United States)

    Lanfear, David E; Hasan, Reema; Gupta, Ramesh C; Williams, Celeste; Czerska, Barbara; Tita, Cristina; Bazari, Rasha; Sabbah, Hani N

    2009-01-01

    Introduction Inotropes are associated with adverse outcomes in heart failure (HF), raising concern they may accelerate myocardial injury. Whether biomarkers of myocardial necrosis, inflammation and apoptosis change in response to acute milrinone administration is not well established. Methods Ten patients with severe HF and reduced cardiac output who were to receive milrinone were studied. Blood samples were taken just before initiation of milrinone and after 24 hours of infusion. Dosing was at the discretion of the patient's attending physician (range 0.25–0.5 mcg/kg/min). Plasma measurements of troponin, myoglobin, N-terminal-pro-BNP, interleukin-6, tumor necrosis factor-α, soluble Fas, and soluble Fas-ligand were performed at both time points. Results Troponin was elevated at baseline in all patients (mean 0.1259 ± 0.17 ng/ml), but there was no significant change after 24 hours of milrinone (mean 0.1345 ± 0.16 ng/ml, p = 0.44). There were significant improvements in interleukin-6, tumor necrosis factor-α, soluble Fas, and soluble Fas-ligand (all p milrinone did not result in exacerbation of myocardial injury but instead was associated with salutary effects on other biomarkers. PMID:19640280

  15. Reliability-based failure cause assessment of collapsed bridge during construction

    International Nuclear Information System (INIS)

    Choi, Hyun-Ho; Lee, Sang-Yoon; Choi, Il-Yoon; Cho, Hyo-Nam; Mahadevan, Sankaran

    2006-01-01

    Until now, in many forensic reports, the failure cause assessments are usually carried out by a deterministic approach so far. However, it may be possible for the forensic investigation to lead to unreasonable results far from the real collapse scenario, because the deterministic approach does not systematically take into account any information on the uncertainties involved in the failures of structures. Reliability-based failure cause assessment (reliability-based forensic engineering) methodology is developed which can incorporate the uncertainties involved in structural failures and structures, and to apply them to the collapsed bridge in order to identify the most critical failure scenario and find the cause that triggered the bridge collapse. Moreover, to save the time and cost of evaluation, an algorithm of automated event tree analysis (ETA) is proposed and possible to automatically calculate the failure probabilities of the failure events and the occurrence probabilities of failure scenarios. Also, for reliability analysis, uncertainties are estimated more reasonably by using the Bayesian approach based on the experimental laboratory testing data in the forensic report. For the applicability, the proposed approach is applied to the Hang-ju Grand Bridge, which collapsed during construction, and compared with deterministic approach

  16. Yogi Detox Tea: A Potential Cause of Acute Liver Failure.

    Science.gov (United States)

    Kesavarapu, Keerthana; Kang, Mitchell; Shin, Jaewook James; Rothstein, Kenneth

    2017-01-01

    We present a case of acute fulminant liver failure from a liver detoxification tea. We present a 60-year-old female with weakness, lethargy, scleral icterus, jaundice, and worsening mental status. She drank herbal tea three times a day for 14 days prior to symptom development. Liver tests were elevated. Remaining laboratory tests and imaging were negative for other etiologies. An ultrasound-guided liver biopsy showed submassive necrosis. A literature search on the ingredients shows six ingredients as having hepatotoxic effects and remaining ingredients as having very sparse hepatoprotective data. Healthcare professionals should discuss herbal medication and tea use and report adverse effects.

  17. Common cause failure investigations using the European Reliability Data System

    International Nuclear Information System (INIS)

    Games, A.M.; Breewood, M.; Amendola, A.; Keller, A.Z.

    1984-01-01

    The European Reliability Data System (ERDS) has provided data for use in investigations into common cause failures (CCFs) in nuclear power plants. These investigations have been made on two levels, at a system and inter-system level. Data have been used from the Component Event Data Bank and from the Licensee Event Report Files, both part of the ERDS. The two studies required different methodologies although both commenced with a temporal sorting procedure for the failure events. The studies demonstrated that different types of common cause failure necessitate different search algorithms, and thus a data search must be closely related to an appropriate CCF classification system, which in the first instance would not be based on causes of failure. (author)

  18. Estimation of common cause failure parameters for diesel generators

    International Nuclear Information System (INIS)

    Tirira, J.; Lanore, J.M.

    2002-10-01

    This paper presents a summary of some results concerning the feedback analysis of French Emergency diesel generator (EDG). The database of common cause failure for EDG has been updated. The data collected covers a period of 10 years. Several latent common cause failure (CCF) events counting in tens are identified. In fact, in this number of events collected, most are potential CCF. From events identified, 15% events are characterized as complete CCF. The database is organised following the structure proposed by 'International Common Cause Data Exchange' (ICDE project). Events collected are analyzed by failure mode and degree of failure. Qualitative analysis of root causes, coupling factors and corrective actions are studied. The exercise of quantitative analysis is in progress for evaluating CCF parameters taking into account the average impact vector and the rate of the independent failures. The interest of the average impact vector approach is that it makes it possible to take into account a wide experience feedback, not limited to complete CCF but including also many events related to partial or potential CCF. It has to be noted that there are no finalized quantitative conclusions yet to be drawn and analysis is in progress for evaluating diesel CCF parameters. In fact, the numerical coding CCF representation of the events uses a part of subjective analysis, which requests a complete and detailed event examination. (authors)

  19. [Acetaminophen (paracetamol) causing renal failure: report on 3 pediatric cases].

    Science.gov (United States)

    Le Vaillant, J; Pellerin, L; Brouard, J; Eckart, P

    2013-06-01

    Renal failure secondary to acetaminophen poisoning is rare and occurs in approximately 1-2 % of patients with acetaminophen overdose. The pathophysiology is still being debated, and renal acetaminophen toxicity consists of acute tubular necrosis, without complication if treated promptly. Renal involvement can sometimes occur without prior liver disease, and early renal manifestations usually occur between the 2nd and 7th day after the acute acetaminophen poisoning. While therapy is exclusively symptomatic, sometimes serious metabolic complications can be observed. The monitoring of renal function should therefore be considered as an integral part of the management of children with acute, severe acetaminophen intoxication. We report 3 cases of adolescents who presented with acute renal failure as a result of voluntary drug intoxication with acetaminophen. One of these 3 girls developed severe renal injury without elevated hepatic transaminases. None of the 3 girls' renal function required hemodialysis, but one of the 3 patients had metabolic complications after her acetaminophen poisoning. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. Fulminant Epstein-Barr virus - infectious mononucleosis in an adult with liver failure, splenic rupture, and spontaneous esophageal bleeding with ensuing esophageal necrosis: a case report.

    Science.gov (United States)

    Busch, Daniel; Hilswicht, Sarah; Schöb, Dominik S; von Trotha, Klaus T; Junge, Karsten; Gassler, Nikolaus; Truong, Son; Neumann, Ulf P; Binnebösel, Marcel

    2014-02-05

    Infectious mononucleosis is a clinical syndrome most commonly associated with primary Epstein-Barr virus infection. The majority of patients with infectious mononucleosis recovers without apparent sequelae. However, infectious mononucleosis may be associated with several acute complications. In this report we present a rare case of esophageal rupture that has never been described in the literature before. We present the case of an 18-year-old Caucasian man affected by severe infectious mononucleosis complicated by fulminant hepatic failure, splenic rupture and esophageal necrosis. Although primary Epstein-Barr virus infection is rarely fatal, fulminant infection may occur - in this case leading to hepatic failure, splenic rupture and esophageal necrosis, subsequently making several surgical interventions necessary. We show here that infectious mononucleosis is not only a strictly medical condition, but can also lead to severe surgical complications.

  1. Thrombotic microangiopathy: An unusual cause of renal failure in rheumatoid arthritis.

    Science.gov (United States)

    Sakthirajan, R; Dhanapriya, J; Dineshkumar, T; Gopalakrishnan, N; Murugan, S; Balasubramaniyan, T

    2017-01-01

    Rheumatoid arthritis (RA) is one of the commonest rheumatological diseases. Renal involvement is not common but can occur as a result of chronic inflammation as part of disease process or drug toxicity. Thrombotic microangiopathy (TMA) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and organ failure of variable severity. Only a few cases of TMA in patients with RA were reported to date. We describe a 45-year-old female patient with RA who presented with oliguria and edema. Renal biopsy showed TMA with patchy cortical necrosis. She improved with hemodialysis and plasmapheresis.

  2. Thrombotic microangiopathy: An unusual cause of renal failure in rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    R Sakthirajan

    2017-01-01

    Full Text Available Rheumatoid arthritis (RA is one of the commonest rheumatological diseases. Renal involvement is not common but can occur as a result of chronic inflammation as part of disease process or drug toxicity. Thrombotic microangiopathy (TMA is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and organ failure of variable severity. Only a few cases of TMA in patients with RA were reported to date. We describe a 45-year-old female patient with RA who presented with oliguria and edema. Renal biopsy showed TMA with patchy cortical necrosis. She improved with hemodialysis and plasmapheresis.

  3. Yogi Detox Tea: A Potential Cause of Acute Liver Failure

    Directory of Open Access Journals (Sweden)

    Keerthana Kesavarapu

    2017-01-01

    Full Text Available We present a case of acute fulminant liver failure from a liver detoxification tea. We present a 60-year-old female with weakness, lethargy, scleral icterus, jaundice, and worsening mental status. She drank herbal tea three times a day for 14 days prior to symptom development. Liver tests were elevated. Remaining laboratory tests and imaging were negative for other etiologies. An ultrasound-guided liver biopsy showed submassive necrosis. A literature search on the ingredients shows six ingredients as having hepatotoxic effects and remaining ingredients as having very sparse hepatoprotective data. Healthcare professionals should discuss herbal medication and tea use and report adverse effects.

  4. Analysis Method of Common Cause Failure on Non-safety Digital Control System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yun Goo; Oh, Eun Gse [KHNP, Daejeon (Korea, Republic of)

    2014-08-15

    The effects of common cause failure on safety digital instrumentation and control system had been considered in defense in depth analysis with safety analysis method. However, the effects of common cause failure on non-safety digital instrumentation and control system also should be evaluated. The common cause failure can be included in credible failure on the non-safety system. In the I and C architecture of nuclear power plant, many design feature has been applied for the functional integrity of control system. One of that is segmentation. Segmentation defenses the propagation of faults in the I and C architecture. Some of effects from common cause failure also can be limited by segmentation. Therefore, in this paper there are two type of failure mode, one is failures in one control group which is segmented, and the other is failures in multiple control group because that the segmentation cannot defense all effects from common cause failure. For each type, the worst failure scenario is needed to be determined, so the analysis method has been proposed in this paper. The evaluation can be qualitative when there is sufficient justification that the effects are bounded in previous safety analysis. When it is not bounded in previous safety analysis, additional analysis should be done with conservative assumptions method of previous safety analysis or best estimation method with realistic assumptions.

  5. Computer aided approach to qualitative and quantitative common cause failure analysis for complex systems

    International Nuclear Information System (INIS)

    Cate, C.L.; Wagner, D.P.; Fussell, J.B.

    1977-01-01

    Common cause failure analysis, also called common mode failure analysis, is an integral part of a complete system reliability analysis. Existing methods of computer aided common cause failure analysis are extended by allowing analysis of the complex systems often encountered in practice. The methods aid in identifying potential common cause failures and also address quantitative common cause failure analysis

  6. Common cause failures - a dilemma in perspective

    International Nuclear Information System (INIS)

    Smith, A.M.; Watson, I.A.

    1980-01-01

    This paper identifies the broad spectrum of common cause failure (CCF) definitions used by various authors. These definitions, as applied to real aircraft and nuclear reactor failure events, lead to a divergence of interpretation and a resultant confusion that obscures meaningful progress in CCF analysis. A new definition is proposed, explained, and tested against the examples. Technical as well as administrative practices are cited as ways to control or eliminate the product defects that lead to CCF. (author)

  7. Femoral Head Avascular Necrosis Is Not Caused by Arthroscopic Posterolateral Femoroplasty.

    Science.gov (United States)

    Rupp, Robert E; Rupp, Sasha N

    2016-05-01

    This study was conducted to identify the risk of avascular necrosis of the femoral head after arthroscopic femoroplasty extending to the posterolateral femoral neck, the source of the primary blood supply to the femoral head. Cam lesions of femoroacetabular impingement are typically anterior along the junction of the femoral head and neck. However, anatomic variations can involve the posterolateral vascular region of the femoral head and neck. Femoroplasty involving this vascular region can lead to injury to the blood supply to the femoral head, with subsequent avascular necrosis. If the posterolateral portion of the cam lesion is preserved, persistent femoroacetabular impingement may occur. A retrospective review identified 112 patients who underwent arthroscopic femoroplasty for femoroacetabular impingement over a 2-year period. Of these patients, 14 had femoroplasty that extended to the posterolateral femoral head. Of this group, 5 had undergone magnetic resonance imaging (MRI) after femoroplasty and the other 9 were contacted to undergo MRI of the hip to evaluate for avascular necrosis. A radiologist and the senior author evaluated all MRI scans specifically for avascular necrosis of the femoral head. All procedures were performed by the senior author. Mean age of the 14 patients (8 women and 6 men) with femoroplasty that extended into the posterolateral vascular region of the femoral head was 44 years (range, 23-69 years). All 14 patients underwent MRI evaluation of the affected hip a mean of 25 months (range, 7-44 months) after femoroplasty. No MRI scans showed evidence of avascular necrosis of the femoral head. Femoroplasty of the posterolateral vascular region of the femoral head is not associated with avascular necrosis. Patients with femoroacetabular impingement and a cam lesion extending to the posterolateral femoral head can undergo femoroplasty of this region without the development of avascular necrosis. [Orthopedics. 2016; 39(3):177-180.]. Copyright

  8. Short term effects of milrinone on biomarkers of necrosis, apoptosis, and inflammation in patients with severe heart failure

    Directory of Open Access Journals (Sweden)

    Tita Cristina

    2009-07-01

    Full Text Available Abstract Introduction Inotropes are associated with adverse outcomes in heart failure (HF, raising concern they may accelerate myocardial injury. Whether biomarkers of myocardial necrosis, inflammation and apoptosis change in response to acute milrinone administration is not well established. Methods Ten patients with severe HF and reduced cardiac output who were to receive milrinone were studied. Blood samples were taken just before initiation of milrinone and after 24 hours of infusion. Dosing was at the discretion of the patient's attending physician (range 0.25–0.5 mcg/kg/min. Plasma measurements of troponin, myoglobin, N-terminal-pro-BNP, interleukin-6, tumor necrosis factor-α, soluble Fas, and soluble Fas-ligand were performed at both time points. Results Troponin was elevated at baseline in all patients (mean 0.1259 ± 0.17 ng/ml, but there was no significant change after 24 hours of milrinone (mean 0.1345 ± 0.16 ng/ml, p = 0.44. There were significant improvements in interleukin-6, tumor necrosis factor-α, soluble Fas, and soluble Fas-ligand (all p Conclusion In conclusion, among patients with severe HF and low cardiac output, ongoing myocardial injury is common, and initiation of milrinone did not result in exacerbation of myocardial injury but instead was associated with salutary effects on other biomarkers.

  9. Exploitation of a component event data bank for common cause failure analysis

    International Nuclear Information System (INIS)

    Games, A.M.; Amendola, A.; Martin, P.

    1985-01-01

    Investigations into using the European Reliability Data System Component Event Data Bank for common cause failure analysis have been carried out. Starting from early exercises where data were analyzed without computer aid, different types of linked multiple failures have been identified. A classification system is proposed based on this experience. It defines a multiple failure event space wherein each category defines causal, modal, temporal and structural links between failures. It is shown that a search algorithm which incorporates the specific interrogative procedures of the data bank can be developed in conjunction with this classification system. It is concluded that the classification scheme and the search algorithm are useful organizational tools in the field of common cause failures studies. However, it is also suggested that the use of the term common cause failure should be avoided since it embodies to many different types of linked multiple failures

  10. Revision of unicompartmental knee arthroplasty: implants used and causes of failure

    Directory of Open Access Journals (Sweden)

    Alan de Paula Mozella

    2014-04-01

    Full Text Available OBJECTIVE: to determine the causes of unicondylar knee arthroplasty failures, as well as identify the implants used and the need of bone grafting in patients undergoing revision UKA in Center of Knee Surgery at the Instituto Nacional de Traumatologia e Ortopedia (INTO in the period between January 1990 and January 2013.METHODS: a retrospective analysis of the medical documentation and imaging, determining the cause of failure of UKA and the time of its occurrence, as well as prosthetic components implanted during the review and the need for bone grafting.RESULTS: in this study, 27 UKA failures in 26 patients were included. Collapse of one or more components was the main cause of failure, occurring in 33% of patients. Aseptic failure was identified in 30% of cases, progression of osteoarthrosis in 15%, infection and pain 7% each, and osteolysis and polyethylene failure in 4% each. Early failure occurred in 41% of all revisions of UKA and late failure in 59%. 23 patients have undergone revision of UK.CONCLUSION: in 35% of revisions the use of bone grafting was needed in tibial area; in 3 cases we needed allograft from Tissue Bank. We did not use metal increase in any of the revision. In one patient we used implant constraint for instability.

  11. A pragmatic approach to estimate alpha factors for common cause failure analysis

    International Nuclear Information System (INIS)

    Hassija, Varun; Senthil Kumar, C.; Velusamy, K.

    2014-01-01

    Highlights: • Estimation of coefficients in alpha factor model for common cause analysis. • A derivation of plant specific alpha factors is demonstrated. • We examine sensitivity of common cause contribution to total system failure. • We compare beta factor and alpha factor models for various redundant configurations. • The use of alpha factors is preferable, especially for large redundant systems. - Abstract: Most of the modern technological systems are deployed with high redundancy but still they fail mainly on account of common cause failures (CCF). Various models such as Beta Factor, Multiple Greek Letter, Binomial Failure Rate and Alpha Factor exists for estimation of risk from common cause failures. Amongst all, alpha factor model is considered most suitable for high redundant systems as it arrives at common cause failure probabilities from a set of ratios of failures and the total component failure probability Q T . In the present study, alpha factor model is applied for the assessment of CCF of safety systems deployed at two nuclear power plants. A method to overcome the difficulties in estimation of the coefficients viz., alpha factors in the model, importance of deriving plant specific alpha factors and sensitivity of common cause contribution to the total system failure probability with respect to hazard imposed by various CCF events is highlighted. An approach described in NUREG/CR-5500 is extended in this study to provide more explicit guidance for a statistical approach to derive plant specific coefficients for CCF analysis especially for high redundant systems. The procedure is expected to aid regulators for independent safety assessment

  12. First description of necrosis in leaves and pseudo-bulbs of Oncidium orchids caused by Burkholderia gladioli in São Paulo State, Brazil

    Science.gov (United States)

    A necrosis of orchid leaves and pseudobulbs was observed in a commercial orchid nursery in Mogi das Cruzes, Sao Paulo, Brazil. The symptoms were water-soaked, brown lesions that can develop into large areas of necrosis that extend throughout the entire plant, ultimately causing death. Bacteria were...

  13. Causes and effects of vital instrumentation and control power supply bus failures

    International Nuclear Information System (INIS)

    Muhlheim, M.D.; Murphy, G.A.

    1987-01-01

    This article presents the results of a study in which the objective was to evaluate nuclear power-plant operating experience to identify the causes and the effects of vital instrumentation and control (I and C) power supply bus failures. Vital I and C power is normally provided to essential instrumentation and controls through either vital d-c or a-c power supply systems. The vital d-c power supply system generally provides control power for starting the diesel generators, for operating electrical circuit breakers, and for controlling various logic circuits. The vital d-c power system also supplies vital a-c power through an inverter. The vital a-c power supply system generally feeds the reactor protection system channels, the engineered safety features actuation system channels, and critical instrumentation in the control room. The leading cause of vital bus failures is inverter failures; other causes are human errors, battery charger failures, and miscellaneous failures. The effects of these failures are that the margin of safety can be degraded by (1) denying key information to the operators, (2) inducing plant transients, (3) causing safety injection actuations, and (4) causing the loss of shutdown cooling flow

  14. A multiple shock model for common cause failures using discrete Markov chain

    International Nuclear Information System (INIS)

    Chung, Dae Wook; Kang, Chang Soon

    1992-01-01

    The most widely used models in common cause analysis are (single) shock models such as the BFR, and the MFR. But, single shock model can not treat the individual common cause separately and has some irrational assumptions. Multiple shock model for common cause failures is developed using Markov chain theory. This model treats each common cause shock as separately and sequently occuring event to implicate the change in failure probability distribution due to each common cause shock. The final failure probability distribution is evaluated and compared with that from the BFR model. The results show that multiple shock model which minimizes the assumptions in the BFR model is more realistic and conservative than the BFR model. The further work for application is the estimations of parameters such as common cause shock rate and component failure probability given a shock,p, through the data analysis

  15. Common cause failure: enhancing defenses against root cause and coupling factor

    Energy Technology Data Exchange (ETDEWEB)

    Kaushik, Poorva; Kim, Sok Chul [KINS, Daejeon (Korea, Republic of)

    2016-10-15

    A Common Cause Failure(CCF) event refers to a specific class of dependent events that result from co-existence of two main factors: Susceptibility of components to fail or become unavailable due to particular root cause of failure, and coupling factor coupling mechanism) that creates the condition for multiple components getting affected. PSA (Probabilistic Safety Assessment) operating experience of Nuclear Power Plants have demonstrated that dependent events such as CCF events are major contributor to risk during operation. From cost-benefit consideration, putting significant design modifications in place to prevent CCF would not be desirable in terms of risk management regulatory effectiveness and efficiency. The aim of this study was to propose feasible defenses against CCF from cost benefit consideration to enhance the safety. This study provides the CDM and CFDM of EDG. Defenses employed against cause and coupling factor can be easily employed in operation and maintenance programme of NPP and are not an additional cost burden. Such enhancement of defense against the CCF can give a modest improvement in CDF. This approach is specifically helpful in plants that are already under operation and significant modifications are not economically feasible.

  16. Patient-reported causes of heart failure in a large European sample

    DEFF Research Database (Denmark)

    Timmermans, Ivy; Denollet, Johan; Pedersen, Susanne S.

    2018-01-01

    ), psychosocial (35%, mainly (work-related) stress), and natural causes (32%, mainly heredity). There were socio-demographic, clinical and psychological group differences between the various categories, and large discrepancies between prevalence of physical risk factors according to medical records and patient...... distress (OR = 1.54, 95% CI = 0.94–2.51, p = 0.09), and behavioral causes and a less threatening view of heart failure (OR = 0.64, 95% CI = 0.40–1.01, p = 0.06). Conclusion: European patients most frequently reported comorbidities, smoking, stress, and heredity as heart failure causes, but their causal......Background: Patients diagnosed with chronic diseases develop perceptions about their disease and its causes, which may influence health behavior and emotional well-being. This is the first study to examine patient-reported causes and their correlates in patients with heart failure. Methods...

  17. The multi-class binomial failure rate model for the treatment of common-cause failures

    International Nuclear Information System (INIS)

    Hauptmanns, U.

    1995-01-01

    The impact of common cause failures (CCF) on PSA results for NPPs is in sharp contrast with the limited quality which can be achieved in their assessment. This is due to the dearth of observations and cannot be remedied in the short run. Therefore the methods employed for calculating failure rates should be devised such as to make the best use of the few available observations on CCF. The Multi-Class Binomial Failure Rate (MCBFR) Model achieves this by assigning observed failures to different classes according to their technical characteristics and applying the BFR formalism to each of these. The results are hence determined by a superposition of BFR type expressions for each class, each of them with its own coupling factor. The model thus obtained flexibly reproduces the dependence of CCF rates on failure multiplicity insinuated by the observed failure multiplicities. This is demonstrated by evaluating CCFs observed for combined impulse pilot valves in German NPPs. (orig.) [de

  18. Acute massive gastric dilatation causing ischaemic necrosis and perforation of the stomach.

    Science.gov (United States)

    Moslim, Maitham A; Mittal, Jay; Falk, Gavin A; Ustin, Jeffrey S; Morris-Stiff, Gareth

    2017-06-15

    Acute massive gastric dilatation (AMGD) is a rare distinctive condition but associates with high morbidity and mortality. Though usually seen in patients with eating disorders, many aetiologies of AMGD have been described. The distension has been reported to cause gastric necrosis with or without perforation, usually within 1-2 days of an inciting event of AMGD.We report the case of a 58-year-old male who presented with gastric perforation associated with AMGD 11 days after surgical relief of a proximal small bowel obstruction. The AMGD arose from a closed loop obstruction between a tumour at the gastro-oesophageal junction and a small bowel obstruction as a result of volvulus around a jejunal feeding tube.To our knowledge, this is the first case of a closed loop obstruction of this aetiology reported in the literature, and the presentation of this patient's AMGD was notable for the delayed onset of gastric necrosis. The patient underwent an exploratory laparotomy and a partial gastrectomy to excise a portion of his perforated stomach. Surgeons should be aware of the possibility of delayed ischaemic gastric perforation in cases of AMGD. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. Effects of Common Cause Failure on Electrical Systems

    International Nuclear Information System (INIS)

    Pepper, Kevin

    2015-01-01

    The essential electrical systems of reactor designs have developed progressively with an increased focus on the use of redundant, segregated and independent safety system equipment 'trains'. In this arrangement, essential safety functions associated with safe shutdown and cooling of the reactor are replicated on near identical electrical systems with each of the trains of safety system equipment supported by a fully rated standby generator. Development in designs has seen the number of trains increased to enable maintenance to be undertaken with reactors at power, improving the economics of the units whilst maintaining nuclear safety. This paper provides a background to common cause failure and provides examples where supporting guidance and international experience is available. It also highlights the regulatory guidance available to UK licensees. Recent examples of common cause failures on plant in the UK are presented together with an issue identified during the recent Generic Design Assessment review of new reactor designs within the UK. It was identified that one design was claiming a very low probability of failure associated with the loss of a single break and no-break voltage level, orders of magnitude below the target figure within ONR's Safety Assessment Principles. On closer scrutiny it was established that a significant safety function provided from identical low voltage switchboards would be lost in the event of a common cause failure affecting these boards. The paper will explain the action that has been taken by the requesting party to improve the resilience of the design and how this impacts on the ONR reliability targets for reactor designs within the UK. (authors)

  20. Insights About Emergency Diesel Generator Failures from the USNRC's Common Cause Failure Database

    International Nuclear Information System (INIS)

    Mosleh, A.; Rasmuson, D.; Marshall, F.; Wierman, T.

    1999-01-01

    The US Nuclear Regulatory Commission has sponsored development of a database of common cause failure events for use in commercial nuclear power plant risk and reliability analyses. This paper presents a summary of the results from analysis of the emergency diesel generator data from the database. The presentation is limited to the overall insights, the design and manufacturing cause and the instrumentation and control sub-system

  1. Data analysis using the Binomial Failure Rate common cause model

    International Nuclear Information System (INIS)

    Atwood, C.L.

    1983-09-01

    This report explains how to use the Binomial Failure Rate (BFR) method to estimate common cause failure rates. The entire method is described, beginning with the conceptual model, and covering practical issues of data preparation, treatment of variation in the failure rates, Bayesian estimation of the quantities of interest, checking the model assumptions for lack of fit to the data, and the ultimate application of the answers

  2. Atrial Fibrillation and Heart Failure - Cause or Effect?

    Science.gov (United States)

    Prabhu, Sandeep; Voskoboinik, Aleksandr; Kaye, David M; Kistler, Peter M

    2017-09-01

    There are emerging epidemics of atrial fibrillation (AF) and heart failure in most developed countries, with a significant health burden. Due to many shared pathophysiological mechanisms, which facilitate the maintenance of each condition, AF and heart failure co-exist in up to 30% of patients. In the circumstance where known structural causes of heart failure (such as myocardial infarction) are absent, patients presenting with both conditions present a unique challenge, particularly as the temporal relationship of each condition can often remain elusive from the clinical history. The question of whether the AF is driving, or significantly contributing to the left ventricular (LV) dysfunction, rather than merely a consequence of heart failure, has become ever more pertinent, especially as catheter ablation now offers a significant advancement over existing rhythm control strategies. This paper will review the inter-related physiological drivers of AF and heart failure before considering the implications from the outcomes of recent clinical trials in patients with AF and heart failure. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  3. ICDE project report: collection and analysis of common-cause failure of check valves

    International Nuclear Information System (INIS)

    Theiss, Klaus; Hessel, Philippe; Werner, Wolfgang

    2003-05-01

    This report documents a study performed on the set of Common Cause Failure (CCF) events of Check Valves (CVs). The events studied here were derived from the International CCF Data Exchange (ICDE) database. Organizations from Canada, Finland, France, Germany, Netherlands, Sweden, Switzerland and the United States contributed with data to this data exchange. This study examines 94 CCF events of CVs reported in the ICDE database by tabulating the data and observing trends. The database contains general information about event attributes like root cause, coupling factor, detection method and corrective action taken. As part of this study, most of these events were reviewed in more detail and characterized by failure cause and failure symptom categories. The study itself begins with an overview of the entire data set in chapter 5. Charts are provided for each of the above-mentioned event attributes. This chapter forms the baseline for chapter 6. The intention of chapter 6 is to give the reader a deeper qualitative insight in the database content beyond that obtained from using the event coding only. Chapter 7 contains the summary of the study results and the conclusions derived from. Approximately 8% of all ICDE events of CVs were complete CCFs (all redundant components had failed). The number of partial CCF events (at least two of the redundant components failed) accounted for 24%. In the remaining 68% of the ICDE events, less than two components had failed completely, and the other components of the observed group only suffered from small defects, incipient degradation or were not affected at all. However, it was found that for more than 75% of the ICDE events the causal factors had a high probability to be shared by all the redundant components. 88 of the 94 reported ICDE events were reviewed in some more detail in Section 6 of this report with respect to failure causes, failure symptoms and failure mechanism. All events classified with a low 'shared cause factor

  4. MRI Findings of Pericardial Fat Necrosis: Case Report

    International Nuclear Information System (INIS)

    Lee, Hyo Hyeok; Ryu, Dae Shick; Jung, Sang Sig; Jung, Seung Mun; Choi, Soo Jung; Shin, Dae Hee

    2011-01-01

    Pericardial fat necrosis is an infrequent cause of acute chest pain and this can mimic acute myocardial infarction and acute pericarditis. We describe here a patient with the magnetic resonance imaging (MRI) findings of pericardial fat necrosis and this was correlated with the computed tomography (CT) findings. The MRI findings may be helpful for distinguishing pericardial fat necrosis from other causes of acute chest pain and from the fat-containing tumors in the cardiophrenic space of the anterior mediastinum.

  5. Dialysis Arteriovenous Fistula Failure and Angioplasty: Intimal Hyperplasia and Other Causes of Access Failure

    Science.gov (United States)

    Duque, Juan C.; Tabbara, Marwan; Martinez, Laisel; Cardona, Jose; Vazquez-Padron, Roberto I; Salman, Loay H

    2016-01-01

    Arteriovenous fistula (AVF) is the preferred hemodialysis access type because it has better patency rates and fewer complications than other access types. However, primary failure remains a common problem impeding AVF maturation and adding to patients’ morbidity and mortality. Juxta-anastomotic (or inflow) stenosis is the most common reason leading to primary failure, and percutaneous transluminal angioplasty (PTA) continues to be the gold standard treatment with excellent success rates. Intimal hyperplasia (IH) has been traditionally blamed as the main pathophysiologic culprit, but new evidence raises doubts regarding the contribution of IH alone to primary failure. We report a 64-year-old man with a two-stage brachio-basilic AVF that was complicated by failure four months after creation. Angiogram showed multiple juxta-anastomotic and mid-fistula stenotic lesions. PTA was successful in assisting maturation and subsequently cannulating AVF for hemodialysis treatment. We failed to identify the underlying cause of stenosis as biopsy specimens from fistula tissue obtained at the time of transposition revealed no occlusive IH. This case emphasizes the need for additional research on factors contributing to AVF failure besides IH, and highlights the need for more therapeutic options to reduce AVF failure rate. PMID:28084215

  6. Possible cause underlying gastric necrosis and perforation: Celiac artery thrombosis

    Directory of Open Access Journals (Sweden)

    Ahmet Peker

    2017-12-01

    Full Text Available In this article, we are sharing a case of a 76-year-old woman with known hypertension, atrial fibrillation,diabetes mellitus, coronary artery disease, who is presenting with stomach necrosis and perforation possibly due to celiac artery thrombosis after newly developed abdominal pain and bloody vomiting. In our case, emergency surgery was planned and the patient refused the operation and was lost at 48 hours of clinical follow-up. We aimed to discuss the etiology of celiac artery thrombosis, briefly. We believe that necrosis and perforation of the stomach due to celiac artery thrombosis deserves to be shared because it is a rare and difficult case to manage.

  7. Ultrasonic scalpel causes greater depth of soft tissue necrosis compared to monopolar electrocautery at standard power level settings in a pig model

    Science.gov (United States)

    2012-01-01

    Background Ultrasonic scalpel (UC) and monopolar electrocautery (ME) are common tools for soft tissue dissection. However, morphological data on the related tissue alteration are discordant. We developed an automatic device for standardized sample excision and compared quality and depth of morphological changes caused by UC and ME in a pig model. Methods 100 tissue samples (5 × 3 cm) of the abdominal wall were excised in 16 pigs. Excisions were randomly performed manually or by using the self-constructed automatic device at standard power levels (60 W cutting in ME, level 5 in UC) for abdominal surgery. Quality of tissue alteration and depth of coagulation necrosis were examined histopathologically. Device (UC vs. ME) and mode (manually vs. automatic) effects were studied by two-way analysis of variance at a significance level of 5%. Results At the investigated power level settings UC and ME induced qualitatively similar coagulation necroses. Mean depth of necrosis was 450.4 ± 457.8 μm for manual UC and 553.5 ± 326.9 μm for automatic UC versus 149.0 ± 74.3 μm for manual ME and 257.6 ± 119.4 μm for automatic ME. Coagulation necrosis was significantly deeper (p < 0.01) when UC was used compared to ME. The mode of excision (manual versus automatic) did not influence the depth of necrosis (p = 0.85). There was no significant interaction between dissection tool and mode of excision (p = 0.93). Conclusions Thermal injury caused by UC and ME results in qualitatively similar coagulation necrosis. The depth of necrosis is significantly greater in UC compared to ME at investigated standard power levels. PMID:22361346

  8. BDD-based reliability evaluation of phased-mission systems with internal/external common-cause failures

    International Nuclear Information System (INIS)

    Xing, Liudong; Levitin, Gregory

    2013-01-01

    Phased-mission systems (PMS) are systems in which multiple non-overlapping phases of operations (or tasks) are accomplished in sequence for a successful mission. Examples of PMS abound in applications such as aerospace, nuclear power, and airborne weapon systems. Reliability analysis of a PMS must consider statistical dependence across different phases as well as dynamics in system configuration, failure criteria, and component behavior. This paper proposes a binary decision diagrams (BDD) based method for the reliability evaluation of non-repairable binary-state PMS with common-cause failures (CCF). CCF are simultaneous failure of multiple system elements, which can be caused by some external factors (e.g., lightning strikes, sudden changes in environment) or by propagated failures originating from some elements within the system. Both the external and internal CCF is considered in this paper. The proposed method is combinatorial, exact, and is applicable to PMS with arbitrary system structures and component failure distributions. An example with different CCF scenarios is analyzed to illustrate the application and advantages of the proposed method. -- Highlights: ► Non-repairable phased-mission systems with common-cause failures are analyzed. ► Common-cause failures caused by internal or external factors are considered. ► A combinatorial algorithm based on binary decision diagrams is suggested

  9. Levamisole-Contaminated Cocaine: An Emergent Cause of Vasculitis and Skin Necrosis

    Directory of Open Access Journals (Sweden)

    Osama Souied

    2014-01-01

    Full Text Available The prevalence of cocaine adulterated with levamisole-induced vasculitis is increasing and physicians should be aware of this unique entity. There have been many reports of cutaneous vasculitis syndrome caused by cocaine which is contaminated with levamisole. Levamisole was used as an antihelminth drug and later was rescinded from use in humans due to adverse effects. Through this paper, we will report a 39-year-old crack cocaine user who presented with purpuric rash and skin necrosis of his ear lobes. Levamisole-induced vasculitis syndrome was suspected. A urine toxicology screen was positive for cocaine, opiates, and marijuana. Blood work revealed positive titres of ANA and p-ANCA, as well as anti-cardiolipin antibody. Biopsy taken from the left ear showed focal acute inflammation, chronic inflammation with thrombus formation, and extravasated blood cells. Treatment was primarily supportive with wound care.

  10. Climate change and the causes of dam failures in Australia

    International Nuclear Information System (INIS)

    Lewis, B.

    2007-01-01

    As a result of poor dam construction methods in Australia and significant droughts occurring over the past 60 years, there is a danger that mistakes made during previous droughts will be repeated. Dams were often built in soils of very low moisture content to ensure a properly compacted bank. As a result of these poor construction methods, the drought years have produced an unusually high number of dam failures. This paper discussed the causes of dam failures such as dispersive clays and defects in associated structures. The discussion on dispersive clays included cracking, piping, tunneling, and slides. Dispersive clays occur in soils whose clay minerals separate into single grains when placed in contact with water and are associated with high soil erodability and their distribution often coincides with the occurrence of erosion gullying, rilling and piping. Dispersive clays in a dam embankment can result in the leaching out of material from the embankment with consequent erosion and failure. Defects in associated structures that were discussed included spillway blockage and outlet pipe blockage. It was concluded that dam failures are seldom due to one particular cause but rather due to one weakness triggering another. It was concluded that failures are difficult and expensive to remedy. 9 refs., 4 figs

  11. 'NTA', a locally named unclear condition that causes failure to thrive ...

    African Journals Online (AJOL)

    'NTA', a locally named unclear condition that causes failure to thrive amongst under five children in southeastern Nigeria: An assessment of mothers' and caregivers' perception of its causes and management.

  12. A hybrid of fuzzy FMEA-AHP to determine factors affecting alternator failure causes

    Directory of Open Access Journals (Sweden)

    Reza Kiani Aslani

    2014-09-01

    Full Text Available This paper presents a method to determine factors influencing alternator failure causes. Failure Mode and Effects Analysis (FMEA is one of the first systematic techniques for failure analysis based on three factors including Probability (P, Severity (S and Detection (D. Traditional FMEA method considers equal weights for all three factors, however, in read-world cases; one may wish to consider various weights. The proposed study develops a mathematical model to determine optimal weights based on analytical hierarchy process technique. The implementation of the proposed study has been demonstrated for a read-world case study of alternator failure causes.

  13. α-Decomposition for estimating parameters in common cause failure modeling based on causal inference

    International Nuclear Information System (INIS)

    Zheng, Xiaoyu; Yamaguchi, Akira; Takata, Takashi

    2013-01-01

    The traditional α-factor model has focused on the occurrence frequencies of common cause failure (CCF) events. Global α-factors in the α-factor model are defined as fractions of failure probability for particular groups of components. However, there are unknown uncertainties in the CCF parameters estimation for the scarcity of available failure data. Joint distributions of CCF parameters are actually determined by a set of possible causes, which are characterized by CCF-triggering abilities and occurrence frequencies. In the present paper, the process of α-decomposition (Kelly-CCF method) is developed to learn about sources of uncertainty in CCF parameter estimation. Moreover, it aims to evaluate CCF risk significances of different causes, which are named as decomposed α-factors. Firstly, a Hybrid Bayesian Network is adopted to reveal the relationship between potential causes and failures. Secondly, because all potential causes have different occurrence frequencies and abilities to trigger dependent failures or independent failures, a regression model is provided and proved by conditional probability. Global α-factors are expressed by explanatory variables (causes’ occurrence frequencies) and parameters (decomposed α-factors). At last, an example is provided to illustrate the process of hierarchical Bayesian inference for the α-decomposition process. This study shows that the α-decomposition method can integrate failure information from cause, component and system level. It can parameterize the CCF risk significance of possible causes and can update probability distributions of global α-factors. Besides, it can provide a reliable way to evaluate uncertainty sources and reduce the uncertainty in probabilistic risk assessment. It is recommended to build databases including CCF parameters and corresponding causes’ occurrence frequency of each targeted system

  14. Analysis of events with common cause failures (CCF) from the international common cause failure date exchange (ICDE); Analyse von Ereignissen mit gemeinsam verursachten Ausfaellen (GVA) aus dem internationalen GVA-Datenaustauschprojekt ICDE

    Energy Technology Data Exchange (ETDEWEB)

    Brueck, Benjamin; Kreuser, Albert; Simon, Julia; Stiller, Jan

    2014-08-15

    Common-cause-failure (CCF) events can significantly impact the availability of safety systems of nuclear power plants. In recognition of this, CCF data are systematically being collected and analyzed in several countries. A comprehensive evaluation of CCF events derived only from the operating experience in German nuclear power plants is not sufficient due to the low probability of occurrence of such events. Therefore it is necessary to make use of the operating experience of other countries using similar technology. In order to be able to use the CCF operating experience from other countries in the aim to carry on the development of the bases for evaluation of CCF GRS decisively co-initiated the setting up of an international common-cause failure working group. This working group has elaborated the project ''International Common-Cause Failure Data Exchange'' (ICDE). The project's objective is to organize a broad exchange of information concerning observed events with relevance to common-cause failures. The tasks for preparation and evaluation of information of the ICDE working group serve for confirmation and extension of the common-cause failure knowledge with regards to probabilistic safety analyses, the better understanding of causes and mechanisms of common-cause failures and the evaluation of preventive measures against the occurrence of common-cause failures. The objectives of the exchange on a long term basis are to - improve the comprehension of CCF events and their causes and their prevention, - generate qualitative insights into the root causes of CCF events which can then be used to derive and assess preventive measures against the occurrence of such events or their consequences, - establish an efficient feedback of experience gained in connection with observed common-cause failure phenomena which could be used e.g. for the development of indicators for risk based inspections, - provide quantitative information regarding the

  15. Root cause analysis of SI line-seated thermal sleeve separation failures

    International Nuclear Information System (INIS)

    Jo, Jong Chull; Jhung, Myung Jo; Kim, Hho Jung

    2004-01-01

    At conventional pressurized water reactors, a thermal sleeve (named simply 'sleeve' hereafter) is seated inside the nozzle part of each Safety Injection (SI) branch pipe to prevent and relieve potential excessive transient thermal stress in the nozzle wall when a cold water is injected during the safety injection mode Recently, mechanical failures that the sleeves are separated from the SI branch pipe and fall into the connected cold leg main pipe were occurred in sequence at Yonggwang units 5 and 6 and Ulchin unit 5. There were many activities and efforts to figure out the causes of those failures with experts' reasoning, but the proposed causes were derived from superficial views rather than physically concrete grounds or analysis results. The prerequisites to find out the root causes of failure mechanism will be to identify the flow situation in the pipe junction area connecting the cold leg with the SI pipe and to know the vibration characteristics of sleeves. This paper investigates the flow field in the pipe junction thru a numerical simulation and vibration characteristics of thermal sleeves thru a modal analysis, from which the root causes of sleeve separation mechanism are analyzed

  16. Failure cause and failure rate evaluation on pumps of BWR plants in PSA. Hypothesis testing for typical or plant specific failure rate of pumps

    International Nuclear Information System (INIS)

    Sanada, Takahiro; Nakamura, Makoto

    2009-01-01

    In support of domestic nuclear industry effort to gather and analyze failure data of components concerning nuclear power plants, Nuclear Information Archives (NUCIA) are published for useful information to help PSA. This report focuses on NUCIA pertaining to pumps in domestic nuclear power plants, and provides the reliable estimation on failure rate of pumps resulting from failure cause analysis and hypothesis testing of classified and plant specific failure rate of pumps for improving quality in PSA. The classified and plant specific failure rate of pumps are estimated by analyzing individual domestic nuclear power plant's data of 26 Boiling Water Reactors (BWRs) concerning functionally structurally classified pump failures reported from beginning of commercial operation to March 31, 2007. (author)

  17. Biomechanical comparisons between a new avascular necrosis of femaral head stem based on Chinese patients with avascular necrosis and two other designs.

    Science.gov (United States)

    Zhang, Qiang; Cheng, Cheng-Kung; Wei, Hung-Wen; Dong, Xiang; Chen, Yi-Ting; Lai, Yu-Shu; Wang, Yan

    2013-01-01

    There is a relatively high failure rate of the femoral component in patients with avascular necrosis at the intermediate-term follow-up. Improving the geometrical fit of the femoral stem against the medullary canal may help to provide long-term survivorship of the hip replacement for patients with avascular necrosis. We designed a specific stem, based on morphometric studies of proximal femoral canals in Chinese avascular necrosis patients and evaluated the stem by finite element analyses, comparing the novel stem with two commercially available and commonly used stems. The morphometric data from avascular necrosis patients showed specific geometric differences in the proximal femoral canal, including profile curves in both the sagittal and coronary planes than the patients with femoral neck fracture. The shorter stemmed prostheses (Fitmore(®) and our stem) performed better than the longer stemmed prosthesis (VerSys(®)). This is the first study to investigate the femoral geometries of Chinese avascular necrosis patients. Our stem provides better stability and is theoretically beneficial to bone ingrowth, which may increase the long-term stability and fixation of the implant.

  18. Histopathological investigation of radiation necrosis. Coagulation necrosis in the irradiated and non-irradiated brain tumors and in the normal brain tissue

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, N [Niigata Univ. (Japan). Brain Research Inst.

    1977-01-01

    Eighty four irradiated tumors (including 59 gliomas) and the surrounding brain tissue were analyzed. In 'normal' brain tissue, typical coagulation necrosis attributable to irradiation was observed in the cerebral white matter, presenting a whitish-yellow color but no remarkable changes in volume. Histologically there was complete desintegration of myelin and axon. Vascular changes included hyalinous thickening, concentric cleavage, fibrinoid degeneration, adventitial fibrosis and edema of small arteries, fibrin thrombi or occlusion of arterioles and capillaries, and telangiectasia of small veins and venules. While other tumors showed hyalinous or fibrous scar tissue and decrease in volume, the gliomas maintained their original volume without residual tumor cells. Massive coagulation necrosis was occasionally found even in full volume, non-irradiated gliomas (controls), although the changes were fewer and not so varied as in typical radiation necrosis. With small dosages, it was difficult to judge whether the necrosis was caused by irradiation or occurred spontaneously. Coagulation necrosis in tumor tissue was found in 25 of 59 cases (42%) of irradiated gliomas, but in only 2 of 49 cases (4%) of the nonirradiated gliomas. In 49 cases no coagulation necrosis of the surrounding tissue was found. Although histopathological judgement is difficult, it is suggested that there is a significant correlation between coagulation necrosis and irradiation. Discussion of the relationship between coagulation necrosis and NSD (nominal standard dose) led to the conclusion that coagulation necrosis will not be caused by irradiation of less than 1400 rets in NSD.

  19. Long-term effects as the cause of failure in electronic components

    International Nuclear Information System (INIS)

    Renz, H.; Kreichgauer, H.

    1989-01-01

    After a brief presentation of the utilisation properties of electronic components, their failure rates are discussed with particular reference to the socalled bath-tub curve. The main emphasis is on the construction and manufacture of integrated circuits and the possible types and causes of failure arising from the individual manufacturing stages (layout faults, internal corrosion, masking and etching errors, leakage currents, inadequate heat removal, etc.). A technical insurance assessment is then provided of the long-term failures associated with technological matters. (orig.) [de

  20. ICDE project report: collection and analysis of common-cause failures of batteries

    International Nuclear Information System (INIS)

    2003-12-01

    This report documents a study performed on the set of Common Cause Failure (CCF) events of batteries (BT). the events studied here were derived from the International CCF Data Exchange (ICDE) database, with contributions from organizations from several countries. 50 events in the ICDE database were studied by tabulating the data and observing the trends. The data span a period from 1980 through 2000. The database contains general information about event attributes such as root cause, coupling factor, common cause component group (CCCG) size, and corrective action. The objective of the report was also to develop the failure mechanisms and phenomena involved in the events, their relationship to the root causes, and possibilities for improvement

  1. Cation dyshomeostasis and cardiomyocyte necrosis: the Fleckenstein hypothesis revisited

    Science.gov (United States)

    Borkowski, Brian J.; Cheema, Yaser; Shahbaz, Atta U.; Bhattacharya, Syamal K.; Weber, Karl T.

    2011-01-01

    An ongoing loss of cardiomyocytes to apoptotic and necrotic cell death pathways contributes to the progressive nature of heart failure. The pathophysiological origins of necrotic cell loss relate to the neurohormonal activation that accompanies acute and chronic stressor states and which includes effector hormones of the adrenergic nervous system. Fifty years ago, Albrecht Fleckenstein and coworkers hypothesized the hyperadrenergic state, which accompanies such stressors, causes cardiomyocyte necrosis based on catecholamine-initiated excessive intracellular Ca2+ accumulation (EICA), and mitochondrial Ca2+ overloading in particular, in which the ensuing dysfunction and structural degeneration of these organelles leads to necrosis. In recent years, two downstream factors have been identified which, together with EICA, constitute a signal–transducer–effector pathway: (i) mitochondria-based induction of oxidative stress, in which the rate of reactive oxygen metabolite generation exceeds their rate of detoxification by endogenous antioxidant defences; and (ii) the opening of the mitochondrial inner membrane permeability transition pore (mPTP) followed by organellar swelling and degeneration. The pathogenesis of stress-related cardiomyopathy syndromes is likely related to this pathway. Other factors which can account for cytotoxicity in stressor states include: hypokalaemia; ionized hypocalcaemia and hypomagnesaemia with resultant elevations in parathyroid hormone serving as a potent mediator of EICA; and hypozincaemia with hyposelenaemia, which compromise antioxidant defences. Herein, we revisit the Fleckenstein hypothesis of EICA in leading to cardiomyocyte necrosis and the central role played by mitochondria. PMID:21398641

  2. External dacryocystorhinostomy in consultants and fellows - a comparison of the causes of failure.

    Science.gov (United States)

    Sullivan, L; Fearnley, T; Al-Maskari, A; El-Hindy, N; Kalantzis, G; Chang, B Y

    2015-01-01

    Failure of primary dacryocystorhinostomy (DCR) often requires revision surgery to inspect the cause of failure and re-establish anatomic patency. This study aims to specifcally compare the anatomical causes of failure noted during revision DCR of primary external DCR (EX-DCR) and compare the difference between consultants and fellows. A retrospective review of 37 patients who underwent revision of a primary external approach DCR over a 7-year-period in a University Hospital. All primary surgery was performed by either a consultant surgeon or senior oculoplastic fellow. Details of the initial pathology prior to primary DCR and grade of operating surgeon were collected along with perioperative surgical findings. The cause of failure of the initial surgery was classified according to perioperative findings. Failure was classified as either inappropriately sized/located ostium or fibrous/membranous soft tissue obstruction of the newly created ostium. The cause of failure of the initial surgery was soft tissue obstruction in 43.3% and an inappropriately sized/located ostium in 56.7%. In those patients whose primary surgery was performed by a consultant, 73.3% were found to have a soft tissue obstruction and 26.7% were found to have an inappropriately sized/ located ostium. In contrast, if initial surgery was performed by a fellow, 22.7% were found to have a soft tissue obstruction and 77.3% an inappropriately sized/ located ostium (p =0.002). Where the primary surgeon has been a trainee there is a trend toward inadequately sized or located ostium being the most likely causative factor in failure of primary EX-DCR.  Hippokratia 2015; 19 (3): 216-218.

  3. Fuel failure in water reactors: Causes and mitigation. Proceedings of a technical meeting

    International Nuclear Information System (INIS)

    2003-03-01

    The objective of this technical meeting (TM) was to review the present knowledge of the causes and mechanisms of fuel failure in water reactors during normal operational conditions. Emphasis has been given to analysis of failure causes and their mitigation by means of design as well as plant and core operation including strategies for operation with failed fuel. Some information on detection techniques (on-line monitoring and diagnostics, flux tilting, sipping techniques, etc) has also been presented. This TM presented also the progress on the above-mentioned subjects since the last meeting held in 1992 (Dimitrovgrad, Russian Federation). The topics covered in the papers were as follows: Experience feedback on fuel reliability (8 papers); Strategies to avoid or mitigate fuel failures (4 papers); Experimental studies on fuel failures and degradation mechanisms (4 papers); Modelling of fuel failure mechanisms (3 papers); Detection and monitoring during operation or outage (4 papers); Modelling and assessment of fuel failures (3 papers)

  4. Procedures for treating common cause failures in safety and reliability studies: Procedural framework and examples

    International Nuclear Information System (INIS)

    Mosleh, A.; Fleming, K.N.; Parry, G.W.; Paula, H.M.; Worledge, D.H.; Rasmuson, D.M.

    1988-01-01

    This report presents a framework for the inclusion of the impact of common cause failures in risk and reliability evaluations. Common cause failures are defined as that cutset of dependent failures for which causes are not explicitly included in the logic model as basic events. The emphasis here is on providing procedures for a practical, systematic approach that can be used to perform and clearly document the analysis. The framework comprises four major stages: (1) System Logic Model Development; (2) Identification of Common Cause Component Groups; (3) Common Cause Modeling and Data Analysis; and (4) System Quantification and Interpretation of Results. The framework and the methods discussed for performing the different stages of the analysis integrate insights obtained from engineering assessments of the system and the historical evidence from multiple failure events into a systematic, reproducible, and defensible analysis. 22 figs., 34 tabs

  5. MRI study of avascular necrosis of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Simizu, Koh; Suguro, Toru; Tsuchiya, Akihiro; Moriya, Hideshige; Nishikawa, Satoru; Arimizu, Noboru [Chiba Univ. (Japan). School of Medicine

    1990-10-01

    Magnetic resonance (MR) images of 70 joints were reviewed in 38 patients with avascular necrosis of the knee or hip joint, whose ages ranged from 19 to 62 years with an average of 41 years. According to causes, steroid induced avascular necrosis was the commonest, accounting for 87% of cases. The remainer of the cases were alcoholic avascular necrosis (8%) and idiopathic avascular necrosis (5%). Steroid induced avascular necrosis was greatly different from idiopathic avascular necrosis in view of clinical manifestations, common sites, and complications of femur head necrosis. Idiopathic avascular necrosis was common in the central part of internal condyle and was confined to one joint. Steroid induced avascular necrosis was common in the posterior part of external condyle and was frequently associated with multiple necroses of the diaphysis. Seventy five percent of the cases were associated with avascular necrosis of the knee. The diagnostic accuracy of the other imaging modalities in avascular necrosis was low (33% for plain roentgenography and 50% for RI examination). Thus, MR was the imaging procedure of choice for detecting avascular necrotic lesions. (N.K.).

  6. MRI study of avascular necrosis of the knee

    International Nuclear Information System (INIS)

    Simizu, Koh; Suguro, Toru; Tsuchiya, Akihiro; Moriya, Hideshige; Nishikawa, Satoru; Arimizu, Noboru

    1990-01-01

    Magnetic resonance (MR) images of 70 joints were reviewed in 38 patients with avascular necrosis of the knee or hip joint, whose ages ranged from 19 to 62 years with an average of 41 years. According to causes, steroid induced avascular necrosis was the commonest, accounting for 87% of cases. The remainer of the cases were alcoholic avascular necrosis (8%) and idiopathic avascular necrosis (5%). Steroid induced avascular necrosis was greatly different from idiopathic avascular necrosis in view of clinical manifestations, common sites, and complications of femur head necrosis. Idiopathic avascular necrosis was common in the central part of internal condyle and was confined to one joint. Steroid induced avascular necrosis was common in the posterior part of external condyle and was frequently associated with multiple necroses of the diaphysis. Seventy five percent of the cases were associated with avascular necrosis of the knee. The diagnostic accuracy of the other imaging modalities in avascular necrosis was low (33% for plain roentgenography and 50% for RI examination). Thus, MR was the imaging procedure of choice for detecting avascular necrotic lesions. (N.K.)

  7. Uncertainties and quantification of common cause failure rates and probabilities for system analyses

    International Nuclear Information System (INIS)

    Vaurio, Jussi K.

    2005-01-01

    Simultaneous failures of multiple components due to common causes at random times are modelled by constant multiple-failure rates. A procedure is described for quantification of common cause failure (CCF) basic event probabilities for system models using plant-specific and multiple-plant failure-event data. Methodology is presented for estimating CCF-rates from event data contaminated with assessment uncertainties. Generalised impact vectors determine the moments for the rates of individual systems or plants. These moments determine the effective numbers of events and observation times to be input to a Bayesian formalism to obtain plant-specific posterior CCF-rates. The rates are used to determine plant-specific common cause event probabilities for the basic events of explicit fault tree models depending on test intervals, test schedules and repair policies. Three methods are presented to determine these probabilities such that the correct time-average system unavailability can be obtained with single fault tree quantification. Recommended numerical values are given and examples illustrate different aspects of the methodology

  8. Endodontic treatment failure caused by arsen utilization as the devitalization material

    Directory of Open Access Journals (Sweden)

    Endang Sukartini

    2008-07-01

    Full Text Available Root canal treatment diagnoses as pulpitis irreversible can be treated in a non-vital condition with devitalization material. Arsenic is one of devitalization material that used in inflammatory pulp tissue before it is going to endodontic treatment. The long-term use of it or the leak of using this arsenic can cause the toxic effect of the pulp tissue. The case is going to report is about the damage of gingival tissue and alveolar that caused by the uncarefullness using of arsenic. Inappropriate arsenic applications cause the leak that able to spread to gingival tissue and will become necrosis. Now a day, the using of arsenic begin to leave because of the toxicity sad effect. This report is going to report how much the damage using arsenic trioxide (As2O3 and the effort from the leakness.

  9. Indomethacin induced avascular necrosis of head of femur

    Science.gov (United States)

    Prathapkumar, K; Smith, I; Attara, G

    2000-01-01

    Chemically induced avascular necrosis of bone is a well documented entity. Indomethacin is one of the causes of this condition but is often difficult to recognise. Review of the literature shows that only one case of indomethacin induced avascular necrosis has been reported in the English language between 1966 and the present.
The case of a young healthy man, who developed avascular necrosis of head of femur after prolonged administration of indomethacin, is reported here.


Keywords: indomethacin; avascular necrosis PMID:10964124

  10. Dependency Analysis Guidance Nordic/German Working Group on Common Cause Failure analysis. Phase 2, Development of Harmonized Approach and Applications for Common Cause Failure Quantification

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Guenter; Johanson, Gunnar; Lindberg, Sandra; Vaurio, Jussi

    2009-03-15

    The Regulatory Code SSMFS 2008:1 of Swedish Radiation Safety Authority (SSM) includes requirements regarding the performance of probabilistic safety assessments (PSA), as well as PSA activities in general. Therefore, the follow-up of these activities is part of the inspection tasks of SSM. According to the SSMFS 2008:1, the safety analyses shall be based on a systematic identification and evaluation of such events, event sequences and other conditions which may lead to a radiological accident. The research report Nordic/German Working Group on Common cause Failure analysis. Phase 2 project report: Development of Harmonized Approach and Applications for Common Cause Failure Quantification has been developed under a contract with the Nordic PSA Group (NPSAG) and its German counterpart VGB, with the aim to create a common experience base for defence and analysis of dependent failures i.e. Common Cause Failures CCF. Phase 2 in this project if a deepened data analyses of CCF events and a demonstration on how the so called impact vectors can be constructed and on how CCF parameters are estimated. The word Guidance in the report title is used in order to indicate a common methodological guidance accepted by the NPSAG, based on current state of the art concerning the analysis of dependent failures and adapted to conditions relevant for Nordic sites. This will make it possible for the utilities to perform cost effective improvements and analyses. The report presents a common attempt by the authorities and the utilities to create a methodology and experience base for defence and analysis of dependent failures. The performed benchmark application has shown how important the interpretation of base data is to obtain robust CCF data and data analyses results. Good features were found in all benchmark approaches. The obtained experiences and approaches should now be used in harmonised procedures. A next step could be to develop and agree on event and formula driven impact vector

  11. Dependency Analysis Guidance Nordic/German Working Group on Common Cause Failure analysis. Phase 2, Development of Harmonized Approach and Applications for Common Cause Failure Quantification

    International Nuclear Information System (INIS)

    Becker, Guenter; Johanson, Gunnar; Lindberg, Sandra; Vaurio, Jussi

    2009-03-01

    The Regulatory Code SSMFS 2008:1 of Swedish Radiation Safety Authority (SSM) includes requirements regarding the performance of probabilistic safety assessments (PSA), as well as PSA activities in general. Therefore, the follow-up of these activities is part of the inspection tasks of SSM. According to the SSMFS 2008:1, the safety analyses shall be based on a systematic identification and evaluation of such events, event sequences and other conditions which may lead to a radiological accident. The research report Nordic/German Working Group on Common cause Failure analysis. Phase 2 project report: Development of Harmonized Approach and Applications for Common Cause Failure Quantification has been developed under a contract with the Nordic PSA Group (NPSAG) and its German counterpart VGB, with the aim to create a common experience base for defence and analysis of dependent failures i.e. Common Cause Failures CCF. Phase 2 in this project if a deepened data analyses of CCF events and a demonstration on how the so called impact vectors can be constructed and on how CCF parameters are estimated. The word Guidance in the report title is used in order to indicate a common methodological guidance accepted by the NPSAG, based on current state of the art concerning the analysis of dependent failures and adapted to conditions relevant for Nordic sites. This will make it possible for the utilities to perform cost effective improvements and analyses. The report presents a common attempt by the authorities and the utilities to create a methodology and experience base for defence and analysis of dependent failures. The performed benchmark application has shown how important the interpretation of base data is to obtain robust CCF data and data analyses results. Good features were found in all benchmark approaches. The obtained experiences and approaches should now be used in harmonised procedures. A next step could be to develop and agree on event and formula driven impact vector

  12. Microscopic polyangiitis: Atypical presentation with extensive small bowel necrosis, diffuse alveolar hemorrhage, and renal failure

    Directory of Open Access Journals (Sweden)

    Justin M. Segraves, M.D.

    2017-01-01

    Full Text Available Microscopic polyangiitis is an uncommon systemic vasculitis of varying severity that is associated with myeloperoxidase (MPO and perinuclear antineutrophil cytoplasmic (p-ANCA antibodies. The most commonly affected organs are the lungs and kidneys. We report on a very unusual case of microscopic polyangiitis presenting with severe mesenteric ischemia in addition to diffuse alveolar hemorrhage and acute renal failure. The patient was initially diagnosed with acute pancreatitis at an outside facility given his severe abdominal pain and elevated pancreatic enzymes. Further investigations after transfer to our facility determined that the patient was actually suffering from a severe exacerbation of previously diagnosed microscopic polyangiitis. He quickly developed diffuse alveolar hemorrhage (DAH necessitating intubation and acute kidney injury (AKI requiring dialysis. He subsequently developed mesenteric ischemia and bowel necrosis resulting in emergent laparotomy and extensive small bowel resection. Physicians need to be aware that microscopic polyangiitis can very rarely present with severe involvement of the abdominal viscera and mesenteric vessels. Severe disease necessitates the use of high dose IV steroids, rituximab or cyclophosphamide, and plasma exchange (PLEX.

  13. Microscopic polyangiitis: Atypical presentation with extensive small bowel necrosis, diffuse alveolar hemorrhage, and renal failure.

    Science.gov (United States)

    Segraves, Justin M; Iyer, Vivek N

    2017-01-01

    Microscopic polyangiitis is an uncommon systemic vasculitis of varying severity that is associated with myeloperoxidase (MPO) and perinuclear antineutrophil cytoplasmic (p-ANCA) antibodies. The most commonly affected organs are the lungs and kidneys. We report on a very unusual case of microscopic polyangiitis presenting with severe mesenteric ischemia in addition to diffuse alveolar hemorrhage and acute renal failure. The patient was initially diagnosed with acute pancreatitis at an outside facility given his severe abdominal pain and elevated pancreatic enzymes. Further investigations after transfer to our facility determined that the patient was actually suffering from a severe exacerbation of previously diagnosed microscopic polyangiitis. He quickly developed diffuse alveolar hemorrhage (DAH) necessitating intubation and acute kidney injury (AKI) requiring dialysis. He subsequently developed mesenteric ischemia and bowel necrosis resulting in emergent laparotomy and extensive small bowel resection. Physicians need to be aware that microscopic polyangiitis can very rarely present with severe involvement of the abdominal viscera and mesenteric vessels. Severe disease necessitates the use of high dose IV steroids, rituximab or cyclophosphamide, and plasma exchange (PLEX).

  14. The root cause analysis of 9DVN002ZV fan failure in Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    Guan Jianjun; Zhang Mingjia

    2005-01-01

    Extensive investigations and detailed analysis of the failure reason of 9DVN002ZV fan in Daya Bay Nuclear Power Station showed that the fan destroy was caused by the failure of non-drive end bear. The direct cause of this bearing' failure was its improper assembly caused by improper maintenance procedure, and the root cause was too small internal radial clearance after mounting. The factor affecting bearing internal radial clearance, the relationship between clearance and operating life time and fan failure process were discussed. (authors)

  15. DRESS syndrome secondary to ibuprofen as a cause of hyperacute liver failure

    Directory of Open Access Journals (Sweden)

    Valentín Roales-Gómez

    2014-08-01

    Full Text Available Acute liver failure has a high mortality and its most frequent cause in Spain is viral infection. In this article, we present a case of fulminant liver failure. The failure is secondary to an idiosyncratic reaction to ibuprofen, an entity included in the DRESS syndrome. This syndrome plays a key role in the differential diagnosis of acute liver failure, since its unfortunate course often requires liver transplantation as the only useful therapeutic weapon. This case illustrates the need for an efficient coordination between hospitals as a key factor for improving the prognosis.

  16. Clinical and CT imaging features of abdominal fat necrosis

    International Nuclear Information System (INIS)

    Zhao Jinkun; Bai Renju

    2013-01-01

    Fat necrosis is a common pathological change at abdominal cross-sectional imaging, and it may cause abdominal pain, mimic pathological change of acute abdomen, or be asymptomatic and accompany other pathophysiologic processes. Fat necrosis is actually the result of steatosis by metabolism or mechanical injury. Common processes that are present in fat necrosis include epiploic appendagitis, infarction of the greater omentum, pancreatitis, and fat necrosis related to trauma or ischemia. As a common fat disease, fat necrosis should be known by clinicians and radiologists. Main content of this text is the clinical symptoms and CT findings of belly fat necrosis and related diseases. (authors)

  17. RIP3-dependent necrosis induced inflammation exacerbates atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Lingjun, E-mail: menglingjun@nibs.ac.cn [College of Biological Sciences, China Agricultural University, Beijing 100094 (China); National Institute of Biological Sciences, Beijing 102206 (China); Jin, Wei [Institute for Immunology, Tsinghua University, Beijing 100084 (China); Wang, Yuhui [Institute of Cardiovascular Sciences, Health Science Center, Peking University, Beijing 100191 (China); Huang, Huanwei; Li, Jia; Zhang, Cai [National Institute of Biological Sciences, Beijing 102206 (China)

    2016-04-29

    Atherothrombotic vascular disease is already the leading cause of mortality worldwide. Atherosclerosis shares features with diseases caused by chronic inflammation. More attention should concentrates on the innate immunity effect atherosclerosis progress. RIP3 (receptor-interacting protein kinase 3) act through the transcription factor named Nr4a3 (Nuclear orphan receptors) to regulate cytokine production. Deletion RIP3 decreases IL-1α production. Injection of anti-IL-1α antibody protects against the progress of atherosclerosis in ApoE −/− mice. RIP3 as a molecular switch in necrosis, controls macrophage necrotic death caused inflammation. Inhibiting necrosis will certainly reduce atherosclerosis through limit inflammation. Necrotic cell death caused systemic inflammation exacerbated cardiovascular disease. Inhibition of necrosis may yield novel therapeutic targets for treatment in years to come. - Highlights: • RIP3 regulate the Nr4a3 to control cytokine production. • Deletion RIP3 decreases IL-1a production. • Injection anti-IL-1a antibody protects against the progress of atherosclerosis. • RIP3 controls macrophage necrotic dead caused inflammation.

  18. RIP3-dependent necrosis induced inflammation exacerbates atherosclerosis

    International Nuclear Information System (INIS)

    Meng, Lingjun; Jin, Wei; Wang, Yuhui; Huang, Huanwei; Li, Jia; Zhang, Cai

    2016-01-01

    Atherothrombotic vascular disease is already the leading cause of mortality worldwide. Atherosclerosis shares features with diseases caused by chronic inflammation. More attention should concentrates on the innate immunity effect atherosclerosis progress. RIP3 (receptor-interacting protein kinase 3) act through the transcription factor named Nr4a3 (Nuclear orphan receptors) to regulate cytokine production. Deletion RIP3 decreases IL-1α production. Injection of anti-IL-1α antibody protects against the progress of atherosclerosis in ApoE −/− mice. RIP3 as a molecular switch in necrosis, controls macrophage necrotic death caused inflammation. Inhibiting necrosis will certainly reduce atherosclerosis through limit inflammation. Necrotic cell death caused systemic inflammation exacerbated cardiovascular disease. Inhibition of necrosis may yield novel therapeutic targets for treatment in years to come. - Highlights: • RIP3 regulate the Nr4a3 to control cytokine production. • Deletion RIP3 decreases IL-1a production. • Injection anti-IL-1a antibody protects against the progress of atherosclerosis. • RIP3 controls macrophage necrotic dead caused inflammation.

  19. Mandibular bone necrosis after use of paraformaldehyde-containing paste

    Directory of Open Access Journals (Sweden)

    Chi-hwan Lee

    2016-11-01

    Full Text Available Paraformaldehyde has been used in the past as a pulpotomy agent. However, it has a severe cytotoxic effect and may cause alveolar bone necrosis. Depulpin, a devitalizing agent containing 49% paraformaldehyde, is no longer used frequently due to its severe side effects. In the two cases described in the present study, Depulpin was used as a devitalizing agent during root canal treatment. It caused a gradual loss of sensibility in adjacent teeth, gingival necrosis, and osteomyelitis. This case report demonstrates the serious side effects of using a paraformaldehyde-containing paste as a devitalizing agent for pulp, particularly mandibular bone necrosis.

  20. Scrub typhus causing neonatal hepatitis with acute liver failure-A case series.

    Science.gov (United States)

    Vajpayee, Shailja; Gupta, R K; Gupta, M L

    2017-05-01

    Neonatal hepatitis with acute liver failure due to varied etiology including various infections is reported in the past. Scrub typhus as a cause of neonatal hepatitis has rarely been reported in literature. A high index of clinical suspicion is required for early diagnosis and timely treatment. Severity and prognosis of the disease varies widely because several different strains of Orientia tsutsugamushi exist with different virulence. Delayed diagnosis can result in complication and significant morbidity and mortality. Here, we report three cases of neonatal hepatitis with acute liver failure caused by scrub typhus to increase awareness.

  1. A COCAP program for the statistical analysis of common cause failure parameters

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Baehyeuk; Jae, Moosung [Hanyang Univ., Seoul (Korea, Republic of). Dept. of Nuclear Engineering

    2016-03-15

    Probabilistic Safety Assessment (PSA) based applications and regulations are becoming more important in the field of nuclear energy. According to the results of a PSA in Korea, the common cause failure evaluates CDF (Core Damage Frequency) as one of the significant factors affecting redundancy of NPPs. The purpose of the study is to develop a COCAP (Common Cause Failure parameter Analysis for PSA) program for the accurate use of the alpha factor model parameter data provided by other countries and for obtaining the indigenous CCF data of NPPs in Korea through Bayesian updating.

  2. Common Cause Failure Analysis for the Digital Plant Protection System

    International Nuclear Information System (INIS)

    Kagn, Hyun Gook; Jang, Seung Cheol

    2005-01-01

    Safety-critical systems such as nuclear power plants adopt the multiple-redundancy design in order to reduce the risk from the single component failure. The digitalized safety-signal generation system is also designed based on the multiple-redundancy strategy which consists of more redundant components. The level of the redundant design of digital systems is usually higher than those of conventional mechanical systems. This higher redundancy would clearly reduce the risk from the single failure of components, but raise the importance of the common cause failure (CCF) analysis. This research aims to develop the practical and realistic method for modeling the CCF in digital safety-critical systems. We propose a simple and practical framework for assessing the CCF probability of digital equipment. Higher level of redundancy causes the difficulty of CCF analysis because it results in impractically large number of CCF events in the fault tree model when we use conventional CCF modeling methods. We apply the simplified alpha-factor (SAF) method to the digital system CCF analysis. The precedent study has shown that SAF method is quite realistic but simple when we consider carefully system success criteria. The first step for using the SAF method is the analysis of target system for determining the function failure cases. That is, the success criteria of the system could be derived from the target system's function and configuration. Based on this analysis, we can calculate the probability of single CCF event which represents the CCF events resulting in the system failure. In addition to the application of SAF method, in order to accommodate the other characteristics of digital technology, we develop a simple concept and several equations for practical use

  3. Trial application of the candidate root cause categorization scheme and preliminary assessment of selected data bases for the root causes of component failures program

    International Nuclear Information System (INIS)

    Bruske, S.Z.; Cadwallader, L.C.; Stepina, P.L.

    1985-04-01

    The objective of the Nuclear Regulatory Commission's (NRC) Root Causes of Component Failures Program is to develop and apply a categorization scheme for identifying root causes of failures for components that comprise safety and safety support systems of nuclear power plants. Results from this program will provide valuable input in the areas of probabilistic risk assessment, reliability assurance, and application of risk assessments in the inspection program. This report presents the trial application and assessment of the candidate root cause categorization scheme to three failure data bases: the In-Plant Reliability Data System (IPRDS), the Licensee Event Report (LER) data base, and the Nuclear Plant Reliability Data System (NPRDS). Results of the trial application/assessment show that significant root cause information can be obtained from these failure data bases

  4. Obstetric acute renal failure 1956-1987.

    Science.gov (United States)

    Turney, J H; Ellis, C M; Parsons, F M

    1989-06-01

    A total of 142 women with severe acute renal failure (ARF) resulting from obstetric causes was treated by dialysis at a single centre from 1956 to 1987. One-year survival was 78.6%, which compares favourably with other causes of ARF. Abortion, haemorrhage and preclampsia comprised 95% of cases, with survival being best (82.9%) with abortion. Survival was adversely affected by increasing age. Acute cortical necrosis (12.7% of patients) carried 100% mortality after 6 years. Follow-up of survivors showed normal renal function up to 31 years following ARF; 25-year patient survival was 71.6%. Improvements in obstetric care and the disappearance of illegal abortions have resulted in a dramatic decline in the incidence of obstetric ARF.

  5. Acute Unilateral Vestibular Failure Does Not Cause Spatial Hemineglect.

    Directory of Open Access Journals (Sweden)

    Julian Conrad

    Full Text Available Visuo-spatial neglect and vestibular disorders have common clinical findings and involve the same cortical areas. We questioned (1 whether visuo-spatial hemineglect is not only a disorder of spatial attention but may also reflect a disorder of higher cortical vestibular function and (2 whether a vestibular tone imbalance due to an acute peripheral dysfunction can also cause symptoms of neglect or extinction. Therefore, patients with an acute unilateral peripheral vestibular failure (VF were tested for symptoms of hemineglect.Twenty-eight patients with acute VF were assessed for signs of vestibular deficits and spatial neglect using clinical measures and various common standardized paper-pencil tests. Neglect severity was evaluated further with the Center of Cancellation method. Pathological neglect test scores were correlated with the degree of vestibular dysfunction determined by the subjective visual vertical and caloric testing.Three patients showed isolated pathological scores in one or the other neglect test, either ipsilesionally or contralesionally to the VF. None of the patients fulfilled the diagnostic criteria of spatial hemineglect or extinction.A vestibular tone imbalance due to unilateral failure of the vestibular endorgan does not cause spatial hemineglect, but evidence indicates it causes mild attentional deficits in both visual hemifields.

  6. Intravenous Milrinone Infusion Improves Congestive Heart Failure Caused by Diastolic Dysfunction

    Science.gov (United States)

    Albrecht, Carlos A.; Giesler, Gregory M.; Kar, Biswajit; Hariharan, Ramesh; Delgado, Reynolds M.

    2005-01-01

    Although there have been significant advances in the medical treatment of heart failure patients with impaired systolic function, very little is known about the diagnosis and treatment of diastolic dysfunction. We report the cases of 3 patients in New York Heart Association functional class IV who had echocardiographically documented diastolic dysfunction as the main cause of heart failure. All 3 patients received medical therapy with long-term milrinone infusion. PMID:16107121

  7. Bevacizumab for the Treatment of Gammaknife Radiosurgery-Induced Brain Radiation Necrosis.

    Science.gov (United States)

    Ma, Yifang; Zheng, Chutian; Feng, Yiping; Xu, Qingsheng

    2017-09-01

    Radiation necrosis is one of the complications of Gammaknife radiosurgery. The traditional treatment of radiation necrosis carries a high risk of failure, Bevacizumab is an antiangiogenic monoclonal antibody against vascular endothelial growth factor, a known mediator of cerebral edema. It can be used to successfully treat brain radiation necrosis. Two patients with a history of small cell lung cancer presented with metastatic disease to the brain. They underwent Gammaknife radiosurgery to brain metastases. Several months later, magnetic resonance imaging showed radiation necrosis with significant surrounding edema. The patients had a poor response to treatment with dexamethasone. They were eventually treated with bevacizumab (5 mg/kg every 2 weeks, 7.5 mg/kg every 3 weeks, respectively), and the treatment resulted in significant clinical and radiographic improvement. Bevacizumab can be successfully used to treat radiation necrosis induced by Gammaknife radiosurgery in patients with cerebral metastases. It is of particular benefit in patients with poor reaction to corticosteroids and other medications.

  8. Investigation into Cause of High Temperature Failure of Boiler Superheater Tube

    Science.gov (United States)

    Ghosh, D.; Ray, S.; Roy, H.; Shukla, A. K.

    2015-04-01

    The failure of the boiler tubes occur due to various reasons like creep, fatigue, corrosion and erosion. This paper highlights a case study of typical premature failure of a final superheater tube of 210 MW thermal power plant boiler. Visual examination, dimensional measurement, chemical analysis, oxide scale thickness measurement, microstructural examination are conducted as part of the investigations. Apart from these investigations, sulfur print, Energy Dispersive spectroscopy (EDS) and X ray diffraction analysis (XRD) are also conducted to ascertain the probable cause of failure of final super heater tube. Finally it has been concluded that the premature failure of the super heater tube can be attributed to the combination of localized high tube metal temperature and loss of metal from the outer surface due to high temperature corrosion. The corrective actions have also been suggested to avoid this type of failure in near future.

  9. Anti-glomerular basement membrane: A rare cause of renal failure in children

    Directory of Open Access Journals (Sweden)

    Indira Agarwal

    2017-01-01

    Full Text Available Anti-glomerular basement membrane (GBM disease is a rare cause of acute renal failure and known to have bad prognosis regarding renal functions recovery and patient survival specially when diagnosed late and presents with severe renal failure that requires dialysis. We report a case of 11-year-old child with acute renal failure secondary to anti-GBM disease and associated with antineutrophil cytoplasmic antibody-positive vasculitis. He was treated with plasmapheresis, steroids, and cyclophosphamide with recovery of his kidney functions.

  10. On the value of redundancy subject to common-cause failures: Toward the resolution of an on-going debate

    International Nuclear Information System (INIS)

    Hoepfer, V.M.; Saleh, J.H.; Marais, K.B.

    2009-01-01

    Common-cause failures (CCF) are one of the more critical and challenging issues for system reliability and risk analyses. Academic interest in modeling CCF, and more broadly in modeling dependent failures, has steadily grown over the years in the number of publications as well as in the sophistication of the analytical tools used. In the past few years, several influential articles have shed doubts on the relevance of redundancy arguing that 'redundancy backfires' through common-cause failures, and that the latter dominate unreliability, thus defeating the purpose of redundancy. In this work, we take issue with some of the results of these publications. In their stead, we provide a nuanced perspective on the (contingent) value of redundancy subject to common-cause failures. First, we review the incremental reliability and MTTF provided by redundancy subject to common-cause failures. Second, we introduce the concept and develop the analytics of the 'redundancy-relevance boundary': we propose this redundancy-relevance boundary as a design-aid tool that provides an answer to the following question: what level of redundancy is relevant or advantageous given a varying prevalence of common-cause failures? We investigate the conditions under which different levels of redundancy provide an incremental MTTF over that of the single component in the face of common-cause failures. Recognizing that redundancy comes at a cost, we also conduct a cost-benefit analysis of redundancy subject to common-cause failures, and demonstrate how this analysis modifies the redundancy-relevance boundary. We show how the value of redundancy is contingent on the prevalence of common-cause failures, the redundancy level considered, and the monadic cost-benefit ratio. Finally we argue that general unqualified criticism of redundancy is misguided, and efforts are better spent for example on understanding and mitigating the potential sources of common-cause failures rather than deriding the concept

  11. Procedures for treating common cause failures in safety and reliability studies: Analytical background and techniques

    International Nuclear Information System (INIS)

    Mosleh, A.; Fleming, K.N.; Parry, G.W.; Paula, H.M.; Worledge, D.H.; Rasmuson, D.M.

    1989-01-01

    Volume I of this report presents a framework for the inclusion of the impact of common cause failures in risk and reliability evaluations. Common cause failures are defined as that subset of dependent failures for which causes are not explicitly included in the logic model as basic events. The emphasis here is on providing procedures for a practical, systematic approach that can be used to perform and clearly document the analysis. The framework and the methods discussed for performing the different stages of the analysis integrate insights obtained from engineering assessments of the system and the historical evidence from multiple failure events into a systematic, reproducible, and defensible analysis. This document, Volume 2, contains a series of appendices that provide additional background and methodological detail on several important topics discussed in Volume I

  12. Systemic arteriovenous malformations as a cause of cardiac failure: Treatment with embolization

    International Nuclear Information System (INIS)

    Smith, E.J.; Hemingway, A.P.; Allison, D.J.

    1987-01-01

    Massive cogenital systemic arteriovenous malformations (AVMs) present considerable management problems for clinicians. Their size, position, and vascularity make successful surgical reaction impossible. Attempts at resection produce only temporary relief of symptoms and cause further disfigurement. Large AVMs give rise to pain, swelling, and distal ischaemia, can erode bone, and give rise to life-threatening hemorrhage, and a massive left or right shunt causes high-output cardiac failure and death. Ten patients (age range, 5-50 years; mean 26 years) have massive AVMs giving rise to high-output cardiac failure (26-28 liters). These patients (seven male, three female), have undergone a total of 43 embolization procedures. The advent of nonionic contrast media, digital subtraction angiography, steel coils, and balloons allows us to successfully treat these patients who until recently were condemned to die in high-output cardiac failure

  13. Causes of Contractor's Business Failure in Developing Countries: The Case of Palestine

    Directory of Open Access Journals (Sweden)

    Sherif Mohamed

    2006-12-01

    Full Text Available The construction industry has unique characteristics that sharply distinguish it from other sectors of the economy. It is fragmented, very sensitive to the economic cycles and political environment, and has a significantly high rate of business failure. Business failure, collapse and bankruptcy are common terms in the industry due to the many risks inherited in how the industry operates. Throughout the world, the relative ease of entry gives rise to a large number of contracting firms competing fiercely in the market exposing many of them to business failure, Palestine is no exception. The objectives of this paper are to report on a research study which aims at exploring the causes of contractor's business failure in Palestine, and investigating their severity from the contractor's point of view. The study's results shows that the main causes of business failure are delay in collecting debt from clients (donors, border closure, heavy dependence on bank loans and payment of high interest on these loans, lack of capital, absence of industry regulations, low profit margin due to high competition, awarding contracts by client to the lowest bidder, and lack of experience in contract management. Based on these findings, recommendations to the Palestinian National Authority (PNA and local contractors are presented in this paper.

  14. Estimation Procedure of Common Cause Failure Parameters for CAFE-PSA

    International Nuclear Information System (INIS)

    Kang, Dae Il; Hwang, M. J.; Han, S. H.

    2009-03-01

    Detailed common cause failure (CCF) analysis generally needs the data for CCF events from other nuclear power plants because the CCF events rarely occur. Since 2002, KAERI has participated in the international common cause failure data exchange (ICDE) project to get data for CCF events. The operation office of the ICDE project sent about 400 CCF event data for emergency diesel generators, motor operated valves, check valves, pumps, and breakers to KAERI in 2009. However, there was no program available to analyze the ICDE CCF event data. Therefore, we developed the CAFE-PSA (common CAuse Failure Event analysis program for PSA) to estimate CCF parameters by using the ICDE CCF event data. With CAFE-PSA, the CCF events in the ICDE database can be qualitatively and quantitatively analyzed. The qualitative analysis results of the ICDE CCF data, by using the CAFE-PSA, showed that the major root cause of CCF events, for motor operated valves, check valves, and pumps, was the fault of their internal parts, and that for emergency diesel generators and breakers was the inadequacy of design/manufacture or construction. The quantitative analysis results of the ICDE CCF data, by using the CAFE-PSA, showed that the estimated Alpha Factors of components, mentioned above, were lower than those previously used in the PSA for domestic nuclear power plants, but were higher than those in USNRC 2007 CCF data. Through performing qualitative and quantitative analysis of the ICDE CCF data, by using the CAFE-PSA, a plan for coping with CCF events for design and operation of nuclear power plants can be produced and reasonable values for CCF parameters can be estimated. In addition, it is expected that the technical adequacy of PSA can be improved

  15. Severe ischemic bowel necrosis caused by terlipressin during treatment of hepatorenal syndrome

    Directory of Open Access Journals (Sweden)

    Hae Rim Kim

    2013-12-01

    Full Text Available Terlipressin is a vasopressin analogue that is widely used in the treatment of hepatorenal syndrome or variceal bleeding. Because it acts mainly on splanchnic vessels, terlipressin has a lower incidence of severe ischemic complications than does vasopressin. However, it can still lead to serious complications such as myocardial infarction, skin necrosis, or bowel ischemia. Herein we report a case of severe ischemic bowel necrosis in a 46-year-old cirrhotic patient treated with terlipressin. Although the patient received bowel resection, death occurred due to ongoing hypotension and metabolic acidosis. Attention should be paid to patients complaining of abdominal pain during treatment with terlipressin.

  16. MDEP Generic Common Position No DICWG-01. Common position on the treatment of common cause failure caused by software within digital safety systems

    International Nuclear Information System (INIS)

    2013-01-01

    Common cause failures (CCF)2 have been a significant safety concern for nuclear power plant systems. The increasing dependence on software-in safety systems for nuclear power plants has increased the safety significance of CCF caused by software, when software in redundant channels or portions of safety systems has some common dependency. For example, the effect of systematic failures can lead to a loss of safety in many ways: unwanted actuations, a safety function is not provided when needed. Therefore, nuclear power plants should be systematically protected from the effects of common cause failures caused by software in DI and C safety systems. Software for nuclear power plant safety systems should be of the high quality necessary to help assure against the loss of safety (i.e. developed with high-quality engineering practices, commensurate quality assurance applied, with continuous improvement through corrective actions based on lessons learned from operating experience). However, demonstrating adequate software quality only through verification and validation activities and controls on the development process has proved to be problematic. Therefore, this common position provides guidance for the assessment of the potential for CCF for software. It is recognized that programmable logic devices do not execute software in the conventional sense; however, the application development process using these devices have many similarities with software development, and the deficiencies that may be introduced during the application development process may induce errors in the programmable logic devices that can result in common cause failures of these devices of a type similar to software common cause failure. Although deficiencies with the potential to give rise to software common cause failures can be introduced at all phases of the software life cycle, this common position will only consider the potential for software common cause failures within digital safety system

  17. A robust Bayesian approach to modeling epistemic uncertainty in common-cause failure models

    International Nuclear Information System (INIS)

    Troffaes, Matthias C.M.; Walter, Gero; Kelly, Dana

    2014-01-01

    In a standard Bayesian approach to the alpha-factor model for common-cause failure, a precise Dirichlet prior distribution models epistemic uncertainty in the alpha-factors. This Dirichlet prior is then updated with observed data to obtain a posterior distribution, which forms the basis for further inferences. In this paper, we adapt the imprecise Dirichlet model of Walley to represent epistemic uncertainty in the alpha-factors. In this approach, epistemic uncertainty is expressed more cautiously via lower and upper expectations for each alpha-factor, along with a learning parameter which determines how quickly the model learns from observed data. For this application, we focus on elicitation of the learning parameter, and find that values in the range of 1 to 10 seem reasonable. The approach is compared with Kelly and Atwood's minimally informative Dirichlet prior for the alpha-factor model, which incorporated precise mean values for the alpha-factors, but which was otherwise quite diffuse. Next, we explore the use of a set of Gamma priors to model epistemic uncertainty in the marginal failure rate, expressed via a lower and upper expectation for this rate, again along with a learning parameter. As zero counts are generally less of an issue here, we find that the choice of this learning parameter is less crucial. Finally, we demonstrate how both epistemic uncertainty models can be combined to arrive at lower and upper expectations for all common-cause failure rates. Thereby, we effectively provide a full sensitivity analysis of common-cause failure rates, properly reflecting epistemic uncertainty of the analyst on all levels of the common-cause failure model

  18. Piroxicam induced submassive necrosis of the liver.

    Science.gov (United States)

    Paterson, D; Kerlin, P; Walker, N; Lynch, S; Strong, R

    1992-01-01

    Several widely used non-steroidal anti-inflammatory drugs have been reported as causing severe hepatitis. Three cases of severe acute hepatitis have been reported in association with piroxicam. A fatal submassive necrosis that occurred in a 68 year old lady who had received piroxicam for 15 months is described. A 48 year old man who developed submassive hepatic necrosis six weeks after beginning piroxicam but was successfully treated with orthotopic liver transplantation is also reported. Piroxicam may induce submassive necrosis of the liver, probably as an idiosyncratic reaction. Images Figure 1 Figure 2 Figure 3 PMID:1446877

  19. Intracellular serpins, firewalls and tissue necrosis.

    Science.gov (United States)

    Marciniak, Stefan J; Lomas, David A

    2008-02-01

    Luke and colleagues have recently attributed a new role to a member of the serpin superfamily of serine proteinase inhibitors. They have used Caenorhabditis elegans to show that an intracellular serpin is crucial for maintaining lysosomal integrity. We examine the role of this firewall in preventing necrosis and attempt to integrate this with current theories of stress-induced protein degradation. We discuss how mutant serpins cause disease either through polymerization or now, perhaps, by unleashing necrosis.

  20. Centrifuge model test of rock slope failure caused by seismic excitation. Plane failure of dip slope

    International Nuclear Information System (INIS)

    Ishimaru, Makoto; Kawai, Tadashi

    2008-01-01

    Recently, it is necessary to assess quantitatively seismic safety of critical facilities against the earthquake induced rock slope failure from the viewpoint of seismic PSA. Under these circumstances, it is essential to evaluate more accurately the possibilities of rock slope failure and the potential failure boundary, which are triggered by earthquake ground motions. The purpose of this study is to analyze dynamic failure characteristics of rock slopes by centrifuge model tests for verification and improvement of the analytical methods. We conducted a centrifuge model test using a dip slope model with discontinuities limitated by Teflon sheets. The centrifugal acceleration was 50G, and the acceleration amplitude of input sin waves increased gradually at every step. The test results were compared with safety factors of the stability analysis based on the limit equilibrium concept. Resultant conclusions are mainly as follows: (1) The slope model collapsed when it was excited by the sine wave of 400gal, which was converted to real field scale, (2) Artificial discontinuities were considerably concerned in the collapse, and the type of collapse was plane failure, (3) From response acceleration records observed at the slope model, we can say that tension cracks were generated near the top of the slope model during excitation, and that might be cause of the collapse, (4) By considering generation of the tension cracks in the stability analysis, correspondence of the analytical results and the experimental results improved. From the obtained results, we need to consider progressive failure in evaluating earthquake induced rock slope failure. (author)

  1. Rin4 causes hybrid necrosis and race-specific resistance in an interspecific lettuce hybrid.

    Science.gov (United States)

    Jeuken, Marieke J W; Zhang, Ningwen W; McHale, Leah K; Pelgrom, Koen; den Boer, Erik; Lindhout, Pim; Michelmore, Richard W; Visser, Richard G F; Niks, Rients E

    2009-10-01

    Some inter- and intraspecific crosses may result in reduced viability or sterility in the offspring, often due to genetic incompatibilities resulting from interactions between two or more loci. Hybrid necrosis is a postzygotic genetic incompatibility that is phenotypically manifested as necrotic lesions on the plant. We observed hybrid necrosis in interspecific lettuce (Lactuca sativa and Lactuca saligna) hybrids that correlated with resistance to downy mildew. Segregation analysis revealed a specific allelic combination at two interacting loci to be responsible. The allelic interaction had two consequences: (1) a quantitative temperature-dependent autoimmunity reaction leading to necrotic lesions, lethality, and quantitative resistance to an otherwise virulent race of Bremia lactucae; and (2) a qualitative temperature-independent race-specific resistance to an avirulent race of B. lactucae. We demonstrated by transient expression and silencing experiments that one of the two interacting genes was Rin4. In Arabidopsis thaliana, RIN4 is known to interact with multiple R gene products, and their interactions result in hypersensitive resistance to Pseudomonas syringae. Site-directed mutation studies on the necrosis-eliciting allele of Rin4 in lettuce showed that three residues were critical for hybrid necrosis.

  2. Digoxin Use and Lower 30-day All-cause Readmission for Medicare Beneficiaries Hospitalized for Heart Failure

    NARCIS (Netherlands)

    Ahmed, Ali; Bourge, Robert C.; Fonarow, Gregg C.; Patel, Kanan; Morgan, Charity J.; Fleg, Jerome L.; Aban, Inmaculada B.; Love, Thomas E.; Yancy, Clyde W.; Deedwania, Prakash; van Veldhuisen, Dirk J.; Filippatos, Gerasimos S.; Anker, Stefan D.; Allman, Richard M.

    BACKGROUND: Heart failure is the leading cause for hospital readmission, the reduction of which is a priority under the Affordable Care Act. Digoxin reduces 30-day all-cause hospital admission in chronic systolic heart failure. Whether digoxin is effective in reducing readmission after

  3. A cause-defense approach to the understanding and analysis of common cause failures

    International Nuclear Information System (INIS)

    Paula, Henrique M.; Campbell, David J.; Parry, Gareth W.; Mitchell, Donald B.; Rasmuson, Dale M.

    1990-03-01

    For improved reliability and safety, nuclear power plants are designed with redundant safety systems, many of which also have redundant trains of equipment within the system. However, the very high reliability theoretically achievable through the use of redundancy is often compromised by single events that can individually render redundant components unavailable (common cause failure [CCF] events). As evidenced by the results of probabilistic risk assessments (PRAs) and by historical experience with nuclear power plant operations, CCF events are usually major contributors to the risk posed by nuclear power plant operation. Thus, it is important that PRAs recognize the potential for CCF events and realistically account for CCF contributions to system unavailability and plant risk. Much progress has been made over the years in the area of CCF analysis, including the development of both qualitative and quantitative analysis methods. Until now, however, CCF methodologies have not explicitly and systematically accounted for the impact of plant-specific defenses, such as design features and operational and maintenance policies, in place to reduce the likelihood of failure occurrences at nuclear power plants. Recognizing the importance of this issue, the NRC has funded a research effort that has focused on developing the cause-defense methodology for CCF analysis and prevention. This report presents the results of this research. Specifically, this report discusses the development of (1) procedures for identifying the potential for CCF events at individual nuclear power plants and (2) cause-defense matrices for analysis of CCF events. Also, new concepts and more precise definitions are introduced to enhance CCF terminology and interpretation of historical event data. (author)

  4. Radiology of renal failure

    International Nuclear Information System (INIS)

    Griffiths, H.J.

    1990-01-01

    This book covers most aspects of imaging studies in patients with renal failure. The initial chapter provides basic information on contrast agents, intravenous urography, and imaging findings in the urinary tract disorders responsible for renal failure and in patients who have undergone transplantation. It illustrates common gastro-intestinal abnormalities seen on barium studies in patients with renal failure. It illustrates the cardiopulmonary complications of renal failure and offers advice for radiologic differentiation. It details different aspects of skeletal changes in renal failure, including a basic description of the pathophysiology of the changes; many excellent illustrations of classic bone changes, arthritis, avascular necrosis, and soft-tissue calcifications; and details of bone mineral analysis

  5. The pacemaker-twiddler's syndrome: an infrequent cause of pacemaker failure.

    Science.gov (United States)

    Salahuddin, Mohammad; Cader, Fathima Aaysha; Nasrin, Sahela; Chowdhury, Mashhud Zia

    2016-01-20

    The pacemaker-twiddler's syndrome is an uncommon cause of pacemaker malfunction. It occurs due to unintentional or deliberate manipulation of the pacemaker pulse generator within its skin pocket by the patient. This causes coiling of the lead and its dislodgement, resulting in failure of ventricular pacing. More commonly reported among elderly females with impaired cognition, the phenomenon usually occurs in the first year following pacemaker implantation. Treatment involves repositioning of the dislodged leads and suture fixation of the lead and pulse generator within its pocket. An 87 year old Bangladeshi lady who underwent a single chamber ventricular pacemaker (VVI mode: i.e. ventricle paced, ventricle sensed, inhibitory mode) implantation with the indication of complete heart block, and presented to us again 7 weeks later, with syncopal attacks. She admitted to repeatedly manipulating the pacemaker generator in her left pectoral region. Physical examination revealed a heart rate of 42 beats/minute, blood pressure 140/80 mmHg and bilateral crackles on lung auscultation. She had no cognitive deficit. An immediate electrocardiogram showed complete heart block with pacemaker spikes and failure to capture. Chest X-ray showed coiled and retracted right ventricular lead and rotated pulse generator. An emergent temporary pace maker was set at a rate of 60 beats per minute. Subsequently, she underwent successful lead repositioning with strong counselling to avoid further twiddling. Twiddler's syndrome should be considered as a cause of pacemaker failure in elderly patients presenting with bradyarrythmias following pacemaker implantation. Chest X-ray and electrocardiograms are simple and easily-available first line investigations for its diagnosis. Lead repositioning is required, however proper patient education and counselling against further manipulation is paramount to long-term management.

  6. Bullous lesions, sweat gland necrosis and rhabdomyolysis in alcoholic coma

    Directory of Open Access Journals (Sweden)

    Neelakandhan Asokan

    2014-01-01

    Full Text Available A 42-year-old male developed hemorrhagic bullae and erosions while in alcohol induced coma. The lesions were limited to areas of the body in prolonged contact with the ground in the comatose state. He developed rhabdomyolysis, progressing to acute renal failure (ARF. Histopathological examination of the skin showed spongiosis, intraepidermal vesicles, and necrosis of eccrine sweat glands with denudation of secretory epithelial lining cells. With supportive treatment and hemodialysis, the patient recovered in 3 weeks time. This is the first reported case of bullous lesions and sweat gland necrosis occurring in alcohol-induced coma complicated by rhabdomyolysis and ARF.

  7. Avascular Necrosis

    Science.gov (United States)

    ... Financial Reports Watchdog Ratings Feedback Contact Select Page Avascular Necrosis Home > Cancer Resources > Late Effects of Treatment > Avascular Necrosis Avascular necrosis (AVN) is a disorder resulting from ...

  8. Diclofenac inhibits tumor necrosis factor-α-induced nuclear factor-κB activation causing synergistic hepatocyte apoptosis.

    Science.gov (United States)

    Fredriksson, Lisa; Herpers, Bram; Benedetti, Giulia; Matadin, Quraisha; Puigvert, Jordi C; de Bont, Hans; Dragovic, Sanja; Vermeulen, Nico P E; Commandeur, Jan N M; Danen, Erik; de Graauw, Marjo; van de Water, Bob

    2011-06-01

    Drug-induced liver injury (DILI) is an important clinical problem. It involves crosstalk between drug toxicity and the immune system, but the exact mechanism at the cellular hepatocyte level is not well understood. Here we studied the mechanism of crosstalk in hepatocyte apoptosis caused by diclofenac and the proinflammatory cytokine tumor necrosis factor α (TNF-α). HepG2 cells were treated with diclofenac followed by TNF-α challenge and subsequent evaluation of necrosis and apoptosis. Diclofenac caused a mild apoptosis of HepG2 cells, which was strongly potentiated by TNF-α. A focused apoptosis machinery short interference RNA (siRNA) library screen identified that this TNF-α-mediated enhancement involved activation of caspase-3 through a caspase-8/Bid/APAF1 pathway. Diclofenac itself induced sustained activation of c-Jun N-terminal kinase (JNK) and inhibition of JNK decreased both diclofenac and diclofenac/TNF-α-induced apoptosis. Live cell imaging of GFPp65/RelA showed that diclofenac dampened the TNF-α-mediated nuclear factor kappaB (NF-κB) translocation oscillation in association with reduced NF-κB transcriptional activity. This was associated with inhibition by diclofenac of the TNF-α-induced phosphorylation of the inhibitor of NF-κB alpha (IκBα). Finally, inhibition of IκB kinase β (IKKβ) with BMS-345541 as well as stable lentiviral short hairpin RNA (shRNA)-based knockdown of p65/RelA sensitized hepatocytes towards diclofenac/TNF-α-induced cytotoxicity. Together, our data suggest a model whereby diclofenac-mediated stress signaling suppresses TNF-α-induced survival signaling routes and sensitizes cells to apoptosis. Copyright © 2011 American Association for the Study of Liver Diseases.

  9. Benchmark exercise of the European Community on common cause failure

    International Nuclear Information System (INIS)

    Doerre, P.

    1986-09-01

    This report summarizes experiences and results of the contractor's contribution to the 'Second Reliability Benchmark Exercise of the European Community on Common Cause Failure' (CCF-RBE). The choice of a method for the treatment of dependent failures in a given reliability analysis depends on the purpose and aim of this analysis as well as on quality and extent of the available data, which may also influence the necessary degree of detail of the analysis. When data are applied to a system with different degree of redundancy, two types of errors have to be avoided which lead to extremely pessimistic assessments. (orig.) With 20 refs., 3 tabs., 1 fig [de

  10. The causes, consequences, and treatment of left or right heart failure

    Directory of Open Access Journals (Sweden)

    Peteiro J

    2011-04-01

    Full Text Available Pablo Pazos-López, Jesús Peteiro-Vázquez, Ana Carcía-Campos, Lourdes García-Bueno, Juan Pablo Abugattas de Torres, Alfonso Castro-BeirasDepartment of Cardiology, Complejo hospitalario Universitario A Coruña, A Coruña, SpainAbstract: Chronic heart failure (HF is a cardiovascular disease of cardinal importance because of several factors: a an increasing occurrence due to the aging of the population, primary and secondary prevention of cardiovascular events, and modern advances in therapy, b a bad prognosis: around 65% of patients are dead within 5 years of diagnosis, c a high economic cost: HF accounts for 1% to 2% of total health care expenditure. This review focuses on the main causes, consequences in terms of morbidity, mortality and costs and treatment of HF.Keywords: heart failure, cause, consequence, treatment

  11. Neutrophil Extracellular Trap-Related Extracellular Histones Cause Vascular Necrosis in Severe GN.

    Science.gov (United States)

    Kumar, Santhosh V R; Kulkarni, Onkar P; Mulay, Shrikant R; Darisipudi, Murthy N; Romoli, Simone; Thomasova, Dana; Scherbaum, Christina R; Hohenstein, Bernd; Hugo, Christian; Müller, Susanna; Liapis, Helen; Anders, Hans-Joachim

    2015-10-01

    Severe GN involves local neutrophil extracellular trap (NET) formation. We hypothesized a local cytotoxic effect of NET-related histone release in necrotizing GN. In vitro, histones from calf thymus or histones released by neutrophils undergoing NETosis killed glomerular endothelial cells, podocytes, and parietal epithelial cells in a dose-dependent manner. Histone-neutralizing agents such as antihistone IgG, activated protein C, or heparin prevented this effect. Histone toxicity on glomeruli ex vivo was Toll-like receptor 2/4 dependent, and lack of TLR2/4 attenuated histone-induced renal thrombotic microangiopathy and glomerular necrosis in mice. Anti-glomerular basement membrane GN involved NET formation and vascular necrosis, whereas blocking NET formation by peptidylarginine inhibition or preemptive anti-histone IgG injection significantly reduced all aspects of GN (i.e., vascular necrosis, podocyte loss, albuminuria, cytokine induction, recruitment or activation of glomerular leukocytes, and glomerular crescent formation). To evaluate histones as a therapeutic target, mice with established GN were treated with three different histone-neutralizing agents. Anti-histone IgG, recombinant activated protein C, and heparin were equally effective in abrogating severe GN, whereas combination therapy had no additive effects. Together, these results indicate that NET-related histone release during GN elicits cytotoxic and immunostimulatory effects. Furthermore, neutralizing extracellular histones is still therapeutic when initiated in established GN. Copyright © 2015 by the American Society of Nephrology.

  12. The mechanism and characteristics of ground movement and strata failure caused by mining

    Energy Technology Data Exchange (ETDEWEB)

    Tianquan, L. (Central Coal Mining Research Institute, Beijing (China))

    1988-01-01

    Analyzes strata movement and ground subsidence caused by underground coal mining. Five types of strata failure during and after underground coal mining are comparatively evaluated: caving zone, fractured zone, bending zone, arched caving, bending with continuous ground movement, sinkhole formation. Effects of coal seam thickness, dip angle, coal panel dimensions, rock stratification and mechanical properties on dimensions and distribution of failure zones in rock strata are investigated. Strata movement during level and steep seam mining is comparatively evaluated. Causes of continuous ground surface deformation and discontinuous deformation are analyzed. Rock strata properties and water influx, which influence sinkhole hazards, are discussed.

  13. Preliminary Analysis of the Common Cause Failure Events for Domestic Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kang, Daeil; Han, Sanghoon

    2007-01-01

    It is known that the common cause failure (CCF) events have a great effect on the safety and probabilistic safety assessment (PSA) results of nuclear power plants (NPPs). However, the domestic studies have been mainly focused on the analysis method and modeling of CCF events. Thus, the analysis of the CCF events for domestic NPPs were performed to establish a domestic database for the CCF events and to deliver them to the operation office of the international common cause failure data exchange (ICDE) project. This paper presents the analysis results of the CCF events for domestic nuclear power plants

  14. Acute tubulo-interstitial nephritis leading to acute renal failure following multiple hornet stings

    Directory of Open Access Journals (Sweden)

    Bambery Pradeep

    2006-11-01

    Full Text Available Abstract Background Hornet stings are generally associated with local and occasionally anaphylactic reactions. Rarely systemic complications like acute renal failure can occur following multiple stings. Renal failure is usually due to development of acute tubular necrosis as a result of intravascular haemolysis, rhabdomyolysis or shock. Rarely it can be following development of acute tubulo-interstitial nephritis. Case presentation We describe a young male, who was stung on face, head, shoulders and upper limbs by multiple hornets (Vespa orientalis. He developed acute renal failure as a result of acute tubulo-interstitial nephritis and responded to steroids. Conclusion Rare causes of acute renal failure like tubulo-interstitial nephritis should be considered in a patient with persistent oliguria and azotemia following multiple hornet stings. Renal biopsy should be undertaken early, as institution of steroid therapy may help in recovery of renal function

  15. ICDE project report on collection and analysis of common-cause failures of centrifugal pumps

    International Nuclear Information System (INIS)

    2000-01-01

    Several member countries of OECD/NEA decided to establish the International Common-Cause Failure Data Exchange (ICDE) Project to encourage multilateral co-operation in the collection and analysis of data relating to Common-Cause Failure (CCF) events. The project was initiated in August 1994 in Sweden and was discussed at meetings in both Sweden and France in 1995. A coding benchmark exercise was defined which was evaluated at meetings held in Germany and in the US in 1996. Subsequently, the exchange of centrifugal pump data was defined; the first phase of this exchange was evaluated at meetings in Switzerland and in France in 1997. The objectives of the ICDE Project are: - to collect and analyse CCF events in the long term so as to better understand such events, their causes, and their prevention, - to generate qualitative insights into the root causes of CCF events which can then be used to derive approaches or mechanisms for their prevention or for mitigating their consequences, - to establish a mechanism for the efficient feedback of experience gained on CCF phenomena, including the development of defences against their occurrence, such as indicators for risk based inspections. The ICDE Project is envisaged as including all possible events of interest, comprising complete, partial and incipient CCF events, called 'ICDE events' in the following. The Project covers the key components of the main safety systems, like centrifugal pumps, diesel generators, motor operated valves, power operated relief valves, safety relief valves, check valves, RPS circuit breakers, batteries and transmitters. Data are collected in an MS ACCESS based databank implemented and maintained at ES-Konsult, Sweden, by NEA appointed clearinghouse. The databank is regularly updated. The clearinghouse and the project group operate it. In the modelling of common-cause failures in systems consisting of several redundant components, two kinds of events are distinguished: a) Unavailability of a

  16. Acute Necrotizing Esophagitis Followed by Duodenal Necrosis

    Science.gov (United States)

    del Hierro, Piedad Magdalena

    2011-01-01

    Acute Necrotizing Esophagitis is an uncommon pathology, characterized by endoscopic finding of diffuse black coloration in esophageal mucosa and histological presence of necrosis in patients with upper gastrointestinal bleeding. The first case of acute necrotizing esophagitis followed by duodenal necrosis, in 81 years old woman with a positive history of Type 2 Diabetes Mellitus, Hypertension, and usual intake of Nonsteroidal Anti-inflammatory drugs, is reported. Although its etiology remains unknown, the duodenal necrosis suggests that ischemia could be the main cause given that the branches off the celiac axis provide common blood supply to the distal esophageal and duodenal tissue. The massive gastroesophagic reflux and NSAID intake could be involved. PMID:27957030

  17. Preliminary review of critical shutdown heat removal items for common cause failure susceptibility on LMFBR's. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Allard, L.T.; Elerath, J.G.

    1976-02-01

    This document presents a common cause failure analysis for Critical LMFBR Shutdown Heat Removal Systems. The report is intended to outline a systematic approach to defining areas with significant potential for common causes of failure, and ultimately provide inputs to the reliability prediction model. A preliminary evaluation of postulatd single initiating causes resulting in multiple failures of LMFBR-SHRS items is presented in Appendix C. This document will be periodically updated to reflect new information and activity.

  18. Finite Element Creep-Fatigue Analysis of a Welded Furnace Roll for Identifying Failure Root Cause

    Science.gov (United States)

    Yang, Y. P.; Mohr, W. C.

    2015-11-01

    Creep-fatigue induced failures are often observed in engineering components operating under high temperature and cyclic loading. Understanding the creep-fatigue damage process and identifying failure root cause are very important for preventing such failures and improving the lifetime of engineering components. Finite element analyses including a heat transfer analysis and a creep-fatigue analysis were conducted to model the cyclic thermal and mechanical process of a furnace roll in a continuous hot-dip coating line. Typically, the roll has a short life, modeling heat convection from hot air inside the furnace. The creep-fatigue analysis was performed by inputting the predicted temperature history and applying mechanical loads. The analysis results showed that the failure was resulted from a creep-fatigue mechanism rather than a creep mechanism. The difference of material properties between the filler metal and the base metal is the root cause for the roll failure, which induces higher creep strain and stress in the interface between the weld and the HAZ.

  19. Collections and Analyses of Common Cause Failure Data for the Korea Standard and Westinghouse Type NPPs

    International Nuclear Information System (INIS)

    Kang, Dae Il; Han, S. H.

    2007-04-01

    The analyses of the CCF events for domestic NPPs were performed to establish the domestic database for the CCF events and to deliver supply them to the operation office of the international common cause failure data exchange (ICDE) project. We collected and analyzed the CCF events of emergency diesel generators, centrifugal pumps, motor-operated valves, check valves, circuit breakers for the Korean Standard Type nuclear power plants (NPPs), Yonggwang Units 3 and 4 and Ulchin Units 3 and 4, and the Westinghouse type NPPs, Kori Unit 3 and 4 and Yonggwang Units 1 and 2. First, the components to be collected and analyzed were classified into the common cause component groups (CCCGs) according to the ICDE coding guidelines. Next, the CCF events were identified based on reviews of the component database for the PSA and its related documents, and consultations with NPP staff. Fourteen CCF events were identified. The ratio of the number of CCF events to that of individual failure events was identified as approximately 10 percentages. However, an in depth review of the CCF events showed that most failure severities of them were identified as partial CCF events, which can be interpreted as some component failures within the CCCGs. Root causes of the CCF events were identified as 9 internal part failures, 2 human errors, 2 design deficiencies, 1 procedure inadequacy. It could be concluded that the major root causes of the CCF events were internal piece part failures

  20. Acute-on-chronic liver failure: causes, clinical characteristics and predictors of mortality

    International Nuclear Information System (INIS)

    Ali, A.; Luck, N.H.

    2017-01-01

    Objective: To determine the causes, characteristics and predictors of mortality in patients with acute-on-chronic liver failure (ACLF). Study Design: Cross-sectional study. Place and Duration of Study:Department of Hepatogastroenterology, Sindh Institute of Urology and Transplantation, Karachi, from July 2014 to June 2016. Methodology:All patients with acute-on-chronic liver disease (ACLD) with ages > 12 were included. Patients with ACLF, as defined by the Asian Pacific Association for the Study of Liver (APASL, 2014) were identified. Predictors of mortality were identified using chi-square or Fisher's exact test. Results: Included in the study were 72 patients with mean age of 36.71 years, 46 (63.9%) being males. Among them, 61 developed ACLF. Commonest causes of chronic liver disease (CLD) were chronic viral hepatitis (37, 51.4%) and autoimmune hepatitis (14, 19.4%). Commonest causes of acute liver injury (ALI) were acute viral hepatitis (24, 33.3%) and drug induced liver injury (DILI) (17, 23.6%). Among those with ACLF, 24 (39.3%) patients died with median survival of 17.1 +-13.5 days. Mortality was significantly associated with Child Turcotte Pugh (CTP) score =>13 (p=0.010), model for end-stage liver disease (MELD) score =>30 (p=0.001), age >40 years (p=0.036), organ failures (OF) =>3 (p 3, CTP =>13, MELD =>30, age >40 years, PSE, renal failure and urosepsis. (author)

  1. Rin4 Causes Hybrid Necrosis and Race-Specific Resistance in an Interspecific Lettuce Hybrid[W

    Science.gov (United States)

    Jeuken, Marieke J.W.; Zhang, Ningwen W.; McHale, Leah K.; Pelgrom, Koen; den Boer, Erik; Lindhout, Pim; Michelmore, Richard W.; Visser, Richard G.F.; Niks, Rients E.

    2009-01-01

    Some inter- and intraspecific crosses may result in reduced viability or sterility in the offspring, often due to genetic incompatibilities resulting from interactions between two or more loci. Hybrid necrosis is a postzygotic genetic incompatibility that is phenotypically manifested as necrotic lesions on the plant. We observed hybrid necrosis in interspecific lettuce (Lactuca sativa and Lactuca saligna) hybrids that correlated with resistance to downy mildew. Segregation analysis revealed a specific allelic combination at two interacting loci to be responsible. The allelic interaction had two consequences: (1) a quantitative temperature-dependent autoimmunity reaction leading to necrotic lesions, lethality, and quantitative resistance to an otherwise virulent race of Bremia lactucae; and (2) a qualitative temperature-independent race-specific resistance to an avirulent race of B. lactucae. We demonstrated by transient expression and silencing experiments that one of the two interacting genes was Rin4. In Arabidopsis thaliana, RIN4 is known to interact with multiple R gene products, and their interactions result in hypersensitive resistance to Pseudomonas syringae. Site-directed mutation studies on the necrosis-eliciting allele of Rin4 in lettuce showed that three residues were critical for hybrid necrosis. PMID:19855048

  2. A fatal case of immune hyperhemolysis with bone marrow necrosis in a patient with sickle cell disease

    Directory of Open Access Journals (Sweden)

    Matthew S. Karafin

    2017-03-01

    Full Text Available In patients with sickle cell disease, hyperhemolysis is a rare but life-threatening complication of transfusion. In this case report, we describe a 61 year-old woman with hemoglobin sickle cell (SC disease and history of alloimmunization who developed hyperhemolysis associated with a transfusion. She was found to have a warm and a clinically-significant cold autoantibody. Severe anemia (Hb 2.7 g/dL with reticulocytopenia and thrombocytopenia prompted a bone marrow biopsy, which demonstrated extensive bone marrow necrosis. Despite treatment, the bone marrow failure did not improve and the patient died on hospital day 38. This case illustrates the potential risks of transfusion in a patient with sickle cell disease, especially one with previous hemolytic reactions. While uncommon, hyperhemolysis can cause death, in this case by extensive bone marrow necrosis. In patients with sickle cell disease, judicious use of red cell transfusions with phenotypically-matched units can diminish, but never completely abrogate, the risks associated with transfusion.

  3. Common cause failure rate estimates for diesel generators in nuclear power plants

    International Nuclear Information System (INIS)

    Steverson, J.A.; Atwood, C.L.

    1982-01-01

    Common cause fault rates for diesel generators in nuclear power plants are estimated, using Licensee Event Reports for the years 1976 through 1978. The binomial failure rate method, used for obtaining the estimates, is briefly explained. Issues discussed include correct classification of common cause events, grouping of the events into homogeneous data subsets, and dealing with plant-to-plant variation

  4. Acute renal failure after rifampicin

    Directory of Open Access Journals (Sweden)

    Adriana Weinberg

    1984-12-01

    Full Text Available A patient with miliary tuberculosis and a chronic urogenital focus is described, who had a borderline renal function at diagnosis and developed overt renal failure upon daily treatment with rifampin (RMP, isoniazid (INH and ethambutol (EMB. This is the first Brazilian report of BMP induced renal damage. A renal biopsy taken on the third day of oliguria showed recent tubular necrosis with acute interstitial inflammation and granuloma formation. The aspect of the granulomatous lesion hightly suggested drug etiology because of the lack of palisading, high incidence of neutrophils and absence of facid-fast bacilli. This is the first presentation of an acute granulomatous interstitial nephritis probably due to RMP. Furthermore the pathogenesis of the renal damage caused by tuberculosis and RMP are discussed.

  5. Diseases causing acute renal failure in a tertiary care hospital

    International Nuclear Information System (INIS)

    Khan, G.; Hussain, K.; Rehman, A.

    2011-01-01

    Objective: This study was done to evaluate frequency of acute renal failure ( ARF ), its causes and out come of the patients. Study Design: Descriptive analytic study Place and Duration of Study: March to Dec 2007 at Combined Military Hospital Lahore. Patients and Methods: All patients, admitted in different wards of the hospital, who developed acute renal failure (doubling of serum creatinine measured on two occasions 12 hours apart), were included in this study. Results: A total of 39 patients were included in the study. Males were 19 (48.71%) and 20 (51.28%) were female. Mean age of patients was 40.2 years (SD=18.0). The major cause was acute Gastroenteritis seen in 23 (58.97%) cases. Others developed ARF due to, Abruptio Placentae 5 (12.82%), Postoperative 5 (12.82%), Eclampsia 3 (7.69%) and Drug induced 3 (7.69%) . Oliguric phase developed in 28 (71.79%) patients and lasted for 8.45 +- 4.16 days. Of these 17 (60.71%) patients had acute gastroenteritis. Conclusion: Gastroenteritis is the most common and important cause of ARF though gynaecological and surgical etiologies must be kept in mind. It is evident that the gynaecological and surgical patients need critical peri-partum and peri-operative monitoring to prevent development of ARF. Early institution of therapy will prevent subsequent morbidity associated with this disease. (author)

  6. ξ common cause failure model and method for defense effectiveness estimation

    International Nuclear Information System (INIS)

    Li Zhaohuan

    1991-08-01

    Two issues have been dealt. One is to develop an event based parametric model called ξ-CCF model. Its parameters are expressed in the fraction of the progressive multiplicities of failure events. By these expressions, the contribution of each multiple failure can be presented more clearly. It can help to select defense tactics against common cause failures. The other is to provide a method which is based on the operational experience and engineering judgement to estimate the effectiveness of defense tactics. It is expressed in terms of reduction matrix for a given tactics on a specific plant in the event by event form. The application of practical example shows that the model in cooperation with the method can simply estimate the effectiveness of defense tactics. It can be easily used by the operators and its application may be extended

  7. (m, M) Machining system with two unreliable servers, mixed spares and common-cause failure

    OpenAIRE

    Jain, Madhu; Mittal, Ragini; Kumari, Rekha

    2015-01-01

    This paper deals with multi-component machine repair model having provision of warm standby units and repair facility consisting of two heterogeneous servers (primary and secondary) to provide repair to the failed units. The failure of operating and standby units may occur individually or due to some common cause. The primary server may fail partially following full failure whereas secondary server faces complete failure only. The life times of servers and operating/standby units and their re...

  8. Causes of liver failure and impact analysis of prognostic risk factors

    Directory of Open Access Journals (Sweden)

    WU Xiaoqing

    2013-04-01

    Full Text Available ObjectiveTo perform a retrospective analysis of patients with liver failure to investigate the causative factors and related risk factors that may affect patient prognosis. MethodsThe clinical, demographic, and laboratory data of 79 consecutive patients diagnosed with liver failure and treated at our hospital between January 2010 and January 2012 (58 males and 21 females; age range: 16-74 years old were collected from the medical records. To identify risk factors of liver failure, the patient variables were assessed by Student’s t-test (continuous variables or Chi-squared test (categorical variables. Multivariate logistic regression analysis was used to investigate the relation between patient outcome and independent risk factors. ResultsThe 79 cases of liver failure were grouped according to disease severity: acute liver failure (n=6; 5 died, subacute liver failure (n=35; 19 died, and chronic liver failure (n=38; 28 died. The overall rate of death was 66%. The majority of cases (81% were related to hepatitis B virus infection. While the three groups of liver failure severity did not show significant differences in sex, mean age, occupation, presence of potassium disorder, total bilirubin (TBil or total cholesterol (CHO at admission, or lowest recorded level of CHO during hospitalization, there were significant intergroup differences in highest recorded TBil level, prothrombin activity (PTA at admission, and highest and lowest recorded PTA, and highest recorded level of CHO. Five independent risk factors were identified: the highest recorded TBil level during hospitalization, presence of infection, hepatorenal syndrome, gastrointestinal bleeding, and hepatic encephalopathy. ConclusionThe major cause of liver failure in this cohort of patients was hepatitis infection, and common biomarkers of liver function, such as TBil, CHO and PTA, may indicate patients with poor prognosis despite clinical intervention. Complications should be addressed as

  9. Acute Hepatopancreatic Necrosis Disease-Causing Vibrio parahaemolyticus Strains Maintain an Antibacterial Type VI Secretion System with Versatile Effector Repertoires.

    Science.gov (United States)

    Li, Peng; Kinch, Lisa N; Ray, Ann; Dalia, Ankur B; Cong, Qian; Nunan, Linda M; Camilli, Andrew; Grishin, Nick V; Salomon, Dor; Orth, Kim

    2017-07-01

    Acute hepatopancreatic necrosis disease (AHPND) is a newly emerging shrimp disease that has severely damaged the global shrimp industry. AHPND is caused by toxic strains of Vibrio parahaemolyticus that have acquired a "selfish plasmid" encoding the deadly binary toxins PirA vp /PirB vp To better understand the repertoire of virulence factors in AHPND-causing V. parahaemolyticus , we conducted a comparative analysis using the genome sequences of the clinical strain RIMD2210633 and of environmental non-AHPND and toxic AHPND isolates of V. parahaemolyticus Interestingly, we found that all of the AHPND strains, but none of the non-AHPND strains, harbor the antibacterial type VI secretion system 1 (T6SS1), which we previously identified and characterized in the clinical isolate RIMD2210633. This finding suggests that the acquisition of this T6SS might confer to AHPND-causing V. parahaemolyticus a fitness advantage over competing bacteria and facilitate shrimp infection. Additionally, we found highly dynamic effector loci in the T6SS1 of AHPND-causing strains, leading to diverse effector repertoires. Our discovery provides novel insights into AHPND-causing pathogens and reveals a potential target for disease control. IMPORTANCE Acute hepatopancreatic necrosis disease (AHPND) is a serious disease that has caused severe damage and significant financial losses to the global shrimp industry. To better understand and prevent this shrimp disease, it is essential to thoroughly characterize its causative agent, Vibrio parahaemolyticus Although the plasmid-encoded binary toxins PirA vp /PirB vp have been shown to be the primary cause of AHPND, it remains unknown whether other virulent factors are commonly present in V. parahaemolyticus and might play important roles during shrimp infection. Here, we analyzed the genome sequences of clinical, non-AHPND, and AHPND strains to characterize their repertoires of key virulence determinants. Our studies reveal that an antibacterial type

  10. The Extracellular Matrix Regulates Granuloma Necrosis in Tuberculosis.

    Science.gov (United States)

    Al Shammari, Basim; Shiomi, Takayuki; Tezera, Liku; Bielecka, Magdalena K; Workman, Victoria; Sathyamoorthy, Tarangini; Mauri, Francesco; Jayasinghe, Suwan N; Robertson, Brian D; D'Armiento, Jeanine; Friedland, Jon S; Elkington, Paul T

    2015-08-01

    A central tenet of tuberculosis pathogenesis is that caseous necrosis leads to extracellular matrix destruction and bacterial transmission. We reconsider the underlying mechanism of tuberculosis pathology and demonstrate that collagen destruction may be a critical initial event, causing caseous necrosis as opposed to resulting from it. In human tuberculosis granulomas, regions of extracellular matrix destruction map to areas of caseous necrosis. In mice, transgenic expression of human matrix metalloproteinase 1 causes caseous necrosis, the pathological hallmark of human tuberculosis. Collagen destruction is the principal pathological difference between humanised mice and wild-type mice with tuberculosis, whereas the release of proinflammatory cytokines does not differ, demonstrating that collagen breakdown may lead to cell death and caseation. To investigate this hypothesis, we developed a 3-dimensional cell culture model of tuberculosis granuloma formation, using bioelectrospray technology. Collagen improved survival of Mycobacterium tuberculosis-infected cells analyzed on the basis of a lactate dehydrogenase release assay, propidium iodide staining, and measurement of the total number of viable cells. Taken together, these findings suggest that collagen destruction is an initial event in tuberculosis immunopathology, leading to caseous necrosis and compromising the immune response, revealing a previously unappreciated role for the extracellular matrix in regulating the host-pathogen interaction. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. PACC information management code for common cause failures analysis

    International Nuclear Information System (INIS)

    Ortega Prieto, P.; Garcia Gay, J.; Mira McWilliams, J.

    1987-01-01

    The purpose of this paper is to present the PACC code, which, through an adequate data management, makes the task of computerized common-mode failure analysis easier. PACC processes and generates information in order to carry out the corresponding qualitative analysis, by means of the boolean technique of transformation of variables, and the quantitative analysis either using one of several parametric methods or a direct data-base. As far as the qualitative analysis is concerned, the code creates several functional forms for the transformation equations according to the user's choice. These equations are subsequently processed by boolean manipulation codes, such as SETS. The quantitative calculations of the code can be carried out in two different ways: either starting from a common cause data-base, or through parametric methods, such as the Binomial Failure Rate Method, the Basic Parameters Method or the Multiple Greek Letter Method, among others. (orig.)

  12. Rhabdomyolysis with acute tubular necrosis following occupational inhalation of thinners.

    Science.gov (United States)

    Ngajilo, D; Ehrlich, R

    2017-07-01

    Thinners are mixtures of organic solvents commonly containing toluene, xylene, acetone, hexane, benzene and methyl isobutyl ketone. This report describes a case of rhabdomyolysis with acute tubular necrosis and renal failure, most likely attributable to toluene, following occupational exposure to thinners while cleaning a steel water tank. These adverse health effects have previously been reported following acute poisoning or intentional inhalation by drug abusers, but rarely in the occupational setting. Poor working conditions, lack of health and safety training and delayed treatment contributed to the onset and severity of the patient's complications. This case emphasizes the need for strict control measures, including adequate ventilation, training on working in confined spaces, appropriate personal protective equipment and emergency rescue procedures in such settings. In addition, rhabdomyolysis, acute tubular necrosis and renal failure should be added to safety data material as possible complications of excessive inhalation of thinners. © The Author 2017. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Necrostatin-1 protects against reactive oxygen species (ROS-induced hepatotoxicity in acetaminophen-induced acute liver failure

    Directory of Open Access Journals (Sweden)

    Kenji Takemoto

    2014-01-01

    Full Text Available Excessive acetaminophen (APAP use is one of the most common causes of acute liver failure. Various types of cell death in the damaged liver are linked to APAP-induced hepatotoxicity, and, of these, necrotic cell death of hepatocytes has been shown to be involved in disease pathogenesis. Until recently, necrosis was commonly considered to be a random and unregulated form of cell death; however, recent studies have identified a previously unknown form of programmed necrosis called receptor-interacting protein kinase (RIPK-dependent necrosis (or necroptosis, which is controlled by the kinases RIPK1 and RIPK3. Although RIPK-dependent necrosis has been implicated in a variety of disease states, including atherosclerosis, myocardial organ damage, stroke, ischemia–reperfusion injury, pancreatitis, and inflammatory bowel disease. However its involvement in APAP-induced hepatocyte necrosis remains elusive. Here, we showed that RIPK1 phosphorylation, which is a hallmark of RIPK-dependent necrosis, was induced by APAP, and the expression pattern of RIPK1 and RIPK3 in the liver overlapped with that of CYP2E1, whose activity around the central vein area has been demonstrated to be critical for the development of APAP-induced hepatic injury. Moreover, a RIPK1 inhibitor ameliorated APAP-induced hepatotoxicity in an animal model, which was underscored by significant suppression of the release of hepatic enzymes and cytokine expression levels. RIPK1 inhibition decreased reactive oxygen species levels produced in APAP-injured hepatocytes, whereas CYP2E1 expression and the depletion rate of total glutathione were unaffected. Of note, RIPK1 inhibition also conferred resistance to oxidative stress in hepatocytes. These data collectively demonstrated a RIPK-dependent necrotic mechanism operates in the APAP-injured liver and inhibition of this pathway may be beneficial for APAP-induced fulminant hepatic failure.

  14. Diencephalic syndrome: a frequently neglected cause of failure to thrive in infants.

    Science.gov (United States)

    Kim, Ahlee; Moon, Jin Soo; Yang, Hye Ran; Chang, Ju Young; Ko, Jae Sung; Seo, Jeong Kee

    2015-01-01

    Diencephalic syndrome is an uncommon cause of failure to thrive in early childhood that is associated with central nervous system neoplasms in the hypothalamic-optic chiasmatic region. It is characterized by complex signs and symptoms related to hypothalamic dysfunction; such nonspecific clinical features may delay diagnosis of the brain tumor. In this study, we analyzed a series of cases in order to define characteristic features of diencephalic syndrome. We performed a retrospective study of 8 patients with diencephalic syndrome (age, 5-38 months). All cases had presented to Seoul National University Children's Hospital between 1995 and 2013, with the chief complaint of poor weight gain. Diencephalic syndrome with central nervous system (CNS) neoplasm was identified in 8 patients. The mean age at which symptoms were noted was 18±10.5 months, and diagnosis after symptom onset was made at the mean age of 11±9.7 months. The mean z score was -3.15±1.14 for weight, -0.12±1.05 for height, 1.01±1.58 for head circumference, and -1.76±1.97 for weight-for-height. Clinical features included failure to thrive (n=8), hydrocephalus (n=5), recurrent vomiting (n=5), strabismus (n=2), developmental delay (n=2), hyperactivity (n=1), nystagmus (n=1), and diarrhea (n=1). On follow-up evaluation, 3 patients showed improvement and remained in stable remission, 2 patients were still receiving chemotherapy, and 3 patients were discharged for palliative care. Diencephalic syndrome is a rare cause of failure to thrive, and diagnosis is frequently delayed. Thus, it is important to consider the possibility of a CNS neoplasm as a cause of failure to thrive and to ensure early diagnosis.

  15. Reliability and Availability Analysis of Some Systems with Common-Cause Failures Using SPICE Circuit Simulation Program

    Directory of Open Access Journals (Sweden)

    Muhammad Taher Abuelma'atti

    1999-01-01

    Full Text Available The effectiveness of SPICE circuit simulation program in calculating probabilities, reliability, steady-state availability and mean-time to failure of repairable systems described by Markov models is demonstrated. Two examples are presented. The first example is a warm standby system with common-cause failures and human errors. The second example is a non-identical unit parallel system with common-cause failures. In both cases recourse to numerical solution is inevitable to obtain the Laplace transforms of the probabilities. Results obtained using SPICE are compared with previously published results obtained using the Laplace transform method. Full SPICE listings are included.

  16. A modified GO-FLOW methodology with common cause failure based on Discrete Time Bayesian Network

    International Nuclear Information System (INIS)

    Fan, Dongming; Wang, Zili; Liu, Linlin; Ren, Yi

    2016-01-01

    Highlights: • Identification of particular causes of failure for common cause failure analysis. • Comparison two formalisms (GO-FLOW and Discrete Time Bayesian network) and establish the correlation between them. • Mapping the GO-FLOW model into Bayesian network model. • Calculated GO-FLOW model with common cause failures based on DTBN. - Abstract: The GO-FLOW methodology is a success-oriented system reliability modelling technique for multi-phase missions involving complex time-dependent, multi-state and common cause failure (CCF) features. However, the analysis algorithm cannot easily handle the multiple shared signals and CCFs. In addition, the simulative algorithm is time consuming when vast multi-state components exist in the model, and the multiple time points of phased mission problems increases the difficulty of the analysis method. In this paper, the Discrete Time Bayesian Network (DTBN) and the GO-FLOW methodology are integrated by the unified mapping rules. Based on these rules, the multi operators can be mapped into DTBN followed by, a complete GO-FLOW model with complex characteristics (e.g. phased mission, multi-state, and CCF) can be converted to the isomorphic DTBN and easily analyzed by utilizing the DTBN. With mature algorithms and tools, the multi-phase mission reliability parameter can be efficiently obtained via the proposed approach without considering the shared signals and the various complex logic operation. Meanwhile, CCF can also arise in the computing process.

  17. Upgrade of Common Cause Failure Modelling of NPP Krsko PSA

    International Nuclear Information System (INIS)

    Vukovic, I.; Mikulicic, V.; Vrbanic, I.

    2006-01-01

    Over the last thirty years the probabilistic safety assessments (PSA) have been increasingly applied in technical engineering practice. Various failure modes of system of concern are mathematically and explicitly modelled by means of fault tree structure. Statistical independence of basic events from which the fault tree is built is not acceptable for an event category referred to as common cause failures (CCF). Based on overview of current international status of modelling of common cause failures in PSA several steps were made related to primary technical basis for methodology and data used for CCF model upgrade project in NPP Krsko (NEK) PSA. As a primary technical basis for methodological aspects of CCF modelling in Krsko PSA the following documents were considered: NUREG/CR-5485, NUREG/CR-4780, and Westinghouse Owners Group documents (WOG) WCAP-15674 and WCAP-15167. Use of these documents is supported by the most relevant guidelines and standards in the field, such as ASME PRA Standard and NRC Regulatory Guide 1.200. WCAP documents are in compliance with NUREG/CR-5485 and NUREG/CR-4780. Additionally, they provide WOG perspective on CCF modelling, which is important to consider since NEK follows WOG practice in resolving many generic and regulatory issues. It is, therefore, desirable that NEK CCF methodology and modelling is in general accordance with recommended WOG approaches. As a primary basis for CCF data needed to estimate CCF model parameters and their uncertainty, the main used documents were: NUREG/CR-5497, NUREG/CR-6268, WCAP-15167, and WCAP-16187. Use of NUREG/CR-5497 and NUREG/CR-6268 as a source of data for CCF parameter estimating is supported by the most relevant industry and regulatory PSA guides and standards currently existing in the field, including WOG. However, the WCAP document WCAP-16187 has provided a basis for CCF parameter values specific to Westinghouse PWR plants. Many of events from NRC / INEEL database were re-classified in WCAP

  18. What causes treatment failure - the patient, primary care, secondary care or inadequate interaction in the health services?

    Directory of Open Access Journals (Sweden)

    Lange Ove

    2011-05-01

    Full Text Available Abstract Background Optimal treatment gives complete relief of symptoms of many disorders. But even if such treatment is available, some patients have persisting complaints. One disorder, from which the patients should achieve complete relief of symptoms with medical or surgical treatment, is gastroesophageal reflux disease (GERD. Despite the fact that such treatment is cheap, safe and easily available; some patients have persistent complaints after contact with the health services. This study evaluates the causes of treatment failure. Methods Twelve patients with GERD and persistent complaints had a semi-structured interview which focused on the patients' evaluation of treatment failure. The interviews were taped, transcribed and evaluated by 18 physicians, (six general practitioners, six gastroenterologists and six gastrointestinal surgeons who completed a questionnaire for each patient. The questionnaires were scored, and the relative responsibility for the failure was attributed to the patient, primary care, secondary care and interaction in the health services. Results Failing interaction in the health services was the most important cause of treatment failure, followed by failure in primary care, secondary care and the patient himself; the relative responsibilities were 35%, 28%, 27% and 10% respectively. There was satisfactory agreement about the causes between doctors with different specialities, but significant inter-individual differences between the doctors. The causes of the failures differed between the patients. Conclusions Treatment failure is a complex problem. Inadequate interaction in the health services seems to be important. Improved communication between parts of the health services and with the patients are areas of improvement.

  19. Structural and functional alterations of catalase induced by acriflavine, a compound causing apoptosis and necrosis.

    Science.gov (United States)

    Attar, Farnoosh; Khavari-Nejad, Sarah; Keyhani, Jacqueline; Keyhani, Ezzatollah

    2009-08-01

    Acriflavine is an antiseptic agent causing both apoptosis and necrosis in yeast. In this work, its effect on the structure and function of catalase, a vital enzyme actively involved in protection against oxidative stress, was investigated. In vitro kinetic studies showed that acriflavine inhibited the enzymatic activity in a competitive manner. The residual activity detectable after preincubation of catalase (1.5 nmol/L) with various concentrations of acriflavine went from 50% to 20% of the control value as the acriflavine concentration increased from 30 to 90 micromol/L. Correlatively with the decrease in activity, alterations in the enzyme's conformation were observed as indicated by fluorescence spectroscopy, circular dichroism spectroscopy, and electronic absorption spectroscopy. The enzyme's intrinsic fluorescence obtained upon excitation at either 297 nm (tryptophan residues) or 280 nm (tyrosine and tryptophan residues) decreased as a function of acriflavine concentration. Circular dichroism studies showed alterations of the protein structure by acriflavine with up to 13% decrease in alpha helix, 16% increase in beta-sheet content, 17% increase in random coil, and 4% increase in beta turns. Spectrophotometric studies showed a blueshift and modifications in the chromicity of catalase at 405 nm, corresponding to an absorbance band due to the enzyme's prosthetic group. Thus, acriflavine induced in vitro a profound change in the structure of catalase so that the enzyme could no longer function. Our results showed that acriflavine, a compound producing apoptosis and necrosis, can have a direct effect on vital functions in cells by disabling key enzymes.

  20. Acute tubular necrosis in a patient with paroxysmal nocturnal hemoglobinuria

    Directory of Open Access Journals (Sweden)

    Eranga S Wijewickrama

    2013-01-01

    Full Text Available Acute renal failure (ARF is a well-recognized complication of paroxysmal nocturnal hemoglobinuria (PNH. The predominant mechanism is intravascular hemolysis resulting in massive hemoglobinuria ARF. We report a case of acute tubular necrosis (ATN developed in the absence of overwhelming evidence of intravascular hemolysis in a 21-year-old man with anemia, who was eventually diagnosed to have PNH. The patient presented with rapidly deteriorating renal functions in the background of iron deficiency anemia, which was attributed to reflux esophagitis. There was no clinical or laboratory evidence of intravascular hemolysis. Renal biopsy revealed ATN with deposition of hemosiderin in the proximal tubular epithelial cells. Diagnosis of PNH was confirmed with a positive Ham′s test and flow cytometry. Our case emphasizes the need to consider ATN as a possible cause for ARF in patients suspected to have PNH even in the absence of overwhelming evidence of intravascular hemolysis.

  1. Mandibular Bone and Soft Tissues Necrosis Caused by an Arsenical Endodontic Preparation Treated with Piezoelectric Device

    Directory of Open Access Journals (Sweden)

    A. Giudice

    2013-01-01

    Full Text Available This paper describes a case of wide mandibular bone necrosis associated with significant soft tissues injury after using an arsenical endodontic preparation in the right lower second molar for endodontic purpose. Authors debate about the hazardous effects of the arsenic paste and the usefulness of piezosurgery for treatment of this drug related bone necrosis.

  2. Oxidative stress and cardiomyocyte necrosis with elevated serum troponins: pathophysiologic mechanisms.

    Science.gov (United States)

    Robinson, Antwon D; Ramanathan, Kodangudi B; McGee, Jesse E; Newman, Kevin P; Weber, Karl T

    2011-08-01

    The progressive nature of heart failure is linked to multiple factors, including an ongoing loss of cardiomyocytes and necrosis. Necrotic cardiomyocytes leave behind several footprints: the spillage of their contents leading to elevations in serum troponins; and morphologic evidence of tissue repair with scarring. The pathophysiologic origins of cardiomyocyte necrosis relates to neurohormonal activation, including the adrenergic nervous system. Catecholamine-initiated excessive intracellular Ca accumulation and mitochondria Ca overloading in particular initiate a mitochondriocentric signal-transducer-effector pathway to necrosis and which includes the induction of oxidative stress and opening of their inner membrane permeability transition pore. Hypokalemia, ionized hypocalcemia and hypomagnesemia, where consequent elevations in parathyroid hormone further account for excessive intracellular Ca accumulation, hypozincemia and hyposelenemia each compromise metalloenzyme-based antioxidant defenses. The necrotic loss of cardiomyocytes and adverse structural remodeling of myocardium is related to the central role played by a mitochondriocentric pathway initiated by neurohormonal activation.

  3. Glutaric Aciduria type I and acute renal failure — Coincidence or causality?

    Directory of Open Access Journals (Sweden)

    Ben Pode-Shakked

    2014-01-01

    Full Text Available Glutaric Aciduria type I (GA-I is a rare organic acidemia, caused by mutations in the GCDH gene, and characterized by encephalopathic crises with neurological sequelae. We report herein a patient with GA-I who presented with severe acute renal failure requiring dialysis, following an acute diarrheal illness. Histopathological evaluation demonstrated acute tubular necrosis, and molecular diagnosis revealed the patient to be homozygous for a previously unreported mutation, p.E64D. As renal impairment is not part of the clinical spectrum typical to GA-I, possible associations of renal failure and the underlying inborn error of metabolism are discussed, including recent advancements made in the understanding of the renal transport of glutaric acid and its derivatives during metabolic disturbance in GA-I.

  4. Pathogenesis of apical periodontitis and the causes of endodontic failures.

    Science.gov (United States)

    Nair, P N R

    2004-11-01

    Apical periodontitis is a sequel to endodontic infection and manifests itself as the host defense response to microbial challenge emanating from the root canal system. It is viewed as a dynamic encounter between microbial factors and host defenses at the interface between infected radicular pulp and periodontal ligament that results in local inflammation, resorption of hard tissues, destruction of other periapical tissues, and eventual formation of various histopathological categories of apical periodontitis, commonly referred to as periapical lesions. The treatment of apical periodontitis, as a disease of root canal infection, consists of eradicating microbes or substantially reducing the microbial load from the root canal and preventing re-infection by orthograde root filling. The treatment has a remarkably high degree of success. Nevertheless, endodontic treatment can fail. Most failures occur when treatment procedures, mostly of a technical nature, have not reached a satisfactory standard for the control and elimination of infection. Even when the highest standards and the most careful procedures are followed, failures still occur. This is because there are root canal regions that cannot be cleaned and obturated with existing equipments, materials, and techniques, and thus, infection can persist. In very rare cases, there are also factors located within the inflamed periapical tissue that can interfere with post-treatment healing of the lesion. The data on the biological causes of endodontic failures are recent and scattered in various journals. This communication is meant to provide a comprehensive overview of the etio-pathogenesis of apical periodontitis and the causes of failed endodontic treatments that can be visualized in radiographs as asymptomatic post-treatment periapical radiolucencies.

  5. Tsunamis caused by submarine slope failures along western Great Bahama Bank.

    Science.gov (United States)

    Schnyder, Jara S D; Eberli, Gregor P; Kirby, James T; Shi, Fengyan; Tehranirad, Babak; Mulder, Thierry; Ducassou, Emmanuelle; Hebbeln, Dierk; Wintersteller, Paul

    2016-11-04

    Submarine slope failures are a likely cause for tsunami generation along the East Coast of the United States. Among potential source areas for such tsunamis are submarine landslides and margin collapses of Bahamian platforms. Numerical models of past events, which have been identified using high-resolution multibeam bathymetric data, reveal possible tsunami impact on Bimini, the Florida Keys, and northern Cuba. Tsunamis caused by slope failures with terminal landslide velocity of 20 ms -1 will either dissipate while traveling through the Straits of Florida, or generate a maximum wave of 1.5 m at the Florida coast. Modeling a worst-case scenario with a calculated terminal landslide velocity generates a wave of 4.5 m height. The modeled margin collapse in southwestern Great Bahama Bank potentially has a high impact on northern Cuba, with wave heights between 3.3 to 9.5 m depending on the collapse velocity. The short distance and travel time from the source areas to densely populated coastal areas would make the Florida Keys and Miami vulnerable to such low-probability but high-impact events.

  6. Adrenal Insufficiency as a Cause of Acute Liver Failure: A Case Report

    Directory of Open Access Journals (Sweden)

    Jamshid Vafaeimanesh

    2013-01-01

    Full Text Available Introduction. Many diseases and conditions can contribute to elevated liver enzymes. Common causes include viral and autoimmune hepatitis, fatty liver, and bile duct diseases, but, in uncommon cases like liver involvement in endocrine disorders, liver failure is also seen. Adrenal insufficiency is the rarest endocrine disorder complicating the liver. In the previously reported cases of adrenal insufficiency, mild liver enzymes elevation was seen but we report a case with severe elevated liver enzymes and liver failure due to adrenal insufficiency. Based on our knowledge, this is the first report in this field. Case Report. A 39-year-old woman was referred to emergency ward due to drowsiness and severe fatigue. Her laboratory tests revealed prothrombin time: 21 sec, alanine aminotransferase (ALT: 2339 IU/L, aspartate aminotransferase (AST: 2002 IU/L, and ALP: 90 IU/L. No common cause of liver involvement was discovered, and eventually, with diagnosis of adrenal insufficiency and corticosteroid therapy, liver enzymes and function became normal. Finally, the patient was discharged with good general condition. Conclusion. With this report, we emphasize adrenal insufficiency (primary or secondary as a reason of liver involvement in unexplainable cases and recommend that any increase in the liver enzymes, even liver failure, in these patients should be observed.

  7. Control of spread of Augusta disease caused by tobacco necrosis virus in tulip by composting residual waste of small bulbs, tunics, roots and soil debris

    NARCIS (Netherlands)

    Asjes, C.J.; Barnhoorn, G.J.

    2002-01-01

    In this study the elimination of the infectious virus/fungus complex of tobacco necrosis virus (TNV; cause of Augusta disease in tulip) and Olpidium brassicae in different soil types and residual waste material of soil debris, small tulip bulbs, roots and tunics by temperature treatments of

  8. Electrical failure during cardiopulmonary bypass: an evaluation of incidence, causes, management and guidelines for preventative measures.

    LENUS (Irish Health Repository)

    Hargrove, M

    2012-02-03

    The incidence of electrical failure during cardiopulmonary bypass (CPB) has been reported to occur in approximately 1 per 1000 cases. While the resultant morbidity and mortality is low, electrical failure is a life-threatening scenario. We report three major electrical failures during CPB in a patient population of 3500 over a 15-year period. These cases involved mains failure and generator shut down, mains failure and generator power surge, and failure of the uninterruptable power supply (UPS), which caused protected sockets to shut down. Protocols for preventative maintenance, necessary equipment, battery backup and guidelines for the successful management of such accidents during CPB are discussed.

  9. A case of systemic lupus erythematosus presenting as bilateral avascular necrosis of femur.

    Science.gov (United States)

    Adikari, Madura; Gunawardane, Aloka; Illangantilaka, Sachithra; Atukorale, Himantha; Rubasinghe, Jeevanie

    2016-08-05

    Avascular necrosis occur as a result of diverse etiology. Chronic inflammatory conditions such as systemic lupus erythematosus considered as a recognize cause. Many cases were reported in systemic lupus erythematosus after treating with corticosteroids. We report a case of a corticosteroid naïve patient presented as bilateral avascular necrosis of femoral head and later progressed to a case of systemic lupus erythematosus. A 26 year old lady presented with right sided hip pain and diagnosed as avascular necrosis of the femoral head. After 6 months she presented a similar pain in left hip, which revealed avascular necrosis of left femoral head as well. A probable cause for her clinical presentation could not be found after extensive clinical and laboratory evaluation. Patient reported high erythrocyte sedimentation rate persistently, and over the next few years progressed as a case of systemic lupus erythematosus. Above case illustrated avascular necrosis could be an early musculoskeletal manifestation of systemic lupus erythematosus even in the absence of corticosteroid administration.

  10. Acute Compartment Syndrome Which Causes Rhabdomyolysis by Carbon Monoxide Poisoning and Sciatic Nerve Injury Associated with It: A Case Report.

    Science.gov (United States)

    Ji, Jung-Woo

    2017-09-01

    Rhabdomyolysis is most frequently caused by soft tissue injury with trauma to the extremities. Non-traumatic rhabdomyolysis may be caused by alcohol or drug abuse, infection, collagen disease, or intensive exercise, but incidence is low. In particular, rhabdomyolysis resulting from carbon monoxide poisoning is especially rare. If caught before death, carbon monoxide poisoning has been shown to cause severe muscle necrosis and severe muscle damage leading to acute renal failure. In cases of carbon-monoxide-induced rhabdomyolsis leading to acute compartment syndrome in the buttocks and sciatic nerve injury are rare. We have experience treating patients with acute compartment syndrome due to rhabdomyolysis following carbon monoxide poisoning. We report the characteristic features of muscle necrosis observed during a decompression operation and magnetic resonance imaging findings with a one-year follow-up in addition to a review of the literature.

  11. Implant failure caused by non-union of bisphosphonate-associated subtrochanteric femur fracture.

    LENUS (Irish Health Repository)

    O'Neill, Barry James

    2014-04-03

    Bisphosphonate use has been identified as a contributory factor in atypical subtrochanteric fracture of the femur. These fractures are commonly treated with an intramedullary device. We present a case of implant failure of an intrameduallary device caused by non-union of an atypical subtrochanteric fracture.

  12. Failure cause analysis and improvement for magnetic component cabinet

    International Nuclear Information System (INIS)

    Ge Bing

    1999-01-01

    The magnetic component cabinet is an important thermal control device fitted on the nuclear power. Because it used a self-saturation amplifier as a primary component, the magnetic component cabinet has some boundness. For increasing the operation safety on the nuclear power, the author describes a new scheme. In order that the magnetic component cabinet can be replaced, the new type component cabinet is developed. Integrate circuit will replace the magnetic components of every function parts. The author has analyzed overall failure cause for magnetic component cabinet and adopted some measures

  13. Common cause failure data collection and analysis for safety-related components of TRIGA SSR-14MW Pitesti, Romania

    International Nuclear Information System (INIS)

    Radu, G.; Mladin, D.

    2003-01-01

    This paper presents a study performed on the set of common cause failures (CCF) of safety-related components of the research reactor TRIGA SSR-14 MW Pitesti. The data collected cover a period of 20 years, from 1979 to 2000. The sources of data are Shift Supervisor Reports, Work Authorizations, and Reactor Log Books. Events collected are analyzed by failure mode and degrees of failure. Qualitative analysis of root causes, coupling factors and corrective actions and quantitative analysis of CCF events are studied. The objective of this work is to develop qualitative insights in the nature of the reported events and to build a site-specific common cause events database. (author)

  14. Successful Treatment of Fibrosing Organising Pneumonia Causing Respiratory Failure with Mycophenolic Acid.

    Science.gov (United States)

    Paul, Christina; Lin-Shaw, Ammy; Joseph, Mariamma; Kwan, Keith; Sergiacomi, Gianluigi; Mura, Marco

    2016-01-01

    Organising pneumonia (OP) is usually promptly responsive to corticosteroid treatment. We describe a series of 3 cases of severe, progressive, biopsy-proven fibrosing OP causing respiratory failure. All cases presented with peribronchial and subpleural consolidations, had a fibro-inflammatory infiltrative component in the alveolar septa, and only had a partial and unsatisfactory response to corticosteroids. However, they responded to mycophenolic acid (MPA) treatment with resolution of respiratory failure as well as clinical and functional improvement. MPA as an additional treatment option for aggressive forms of fibrosing OP and interstitial lung disease needs to be further explored. © 2016 S. Karger AG, Basel.

  15. Pathological features of cerebral radiation necrosis - Part I

    International Nuclear Information System (INIS)

    Lefaix, J.L.

    1992-01-01

    Cerebral radiation necrosis is a major hazard of radiation therapy involving delivery of high doses of radiation to the brain. It is generally irreversible and frequently leads to death from brain necrosis. Necrosis has been reported with total doses of 50-60 Gy, delivered in conventional fractions of 1.7 to 2 Gy daily. Signs and symptoms depend upon the volume of brain irradiated and are frequently those of an intracranial mass. Injury tends to be more severe in white matter and may be present as an area of gliosis or frank necrosis. Possible causes include some direct effect of radiation on glial cells, vascular changes and the action of an immunological mechanism. The weight of evidence suggests that demyelination is important in the early delayed reaction, and that vascular changes gradually become more important in the late delayed reactions, several months to years after treatment. Late delayed radiation injuries of the brain and spinal cord are reviewed in man, dog, monkey and rat

  16. Ultrasonic scalpel causes greater depth of soft tissue necrosis compared to monopolar electrocautery at standard power level settings in a pig model.

    Science.gov (United States)

    Homayounfar, Kia; Meis, Johanna; Jung, Klaus; Klosterhalfen, Bernd; Sprenger, Thilo; Conradi, Lena-Christin; Langer, Claus; Becker, Heinz

    2012-02-23

    Ultrasonic scalpel (UC) and monopolar electrocautery (ME) are common tools for soft tissue dissection. However, morphological data on the related tissue alteration are discordant. We developed an automatic device for standardized sample excision and compared quality and depth of morphological changes caused by UC and ME in a pig model. 100 tissue samples (5 × 3 cm) of the abdominal wall were excised in 16 pigs. Excisions were randomly performed manually or by using the self-constructed automatic device at standard power levels (60 W cutting in ME, level 5 in UC) for abdominal surgery. Quality of tissue alteration and depth of coagulation necrosis were examined histopathologically. Device (UC vs. ME) and mode (manually vs. automatic) effects were studied by two-way analysis of variance at a significance level of 5%. At the investigated power level settings UC and ME induced qualitatively similar coagulation necroses. Mean depth of necrosis was 450.4 ± 457.8 μm for manual UC and 553.5 ± 326.9 μm for automatic UC versus 149.0 ± 74.3 μm for manual ME and 257.6 ± 119.4 μm for automatic ME. Coagulation necrosis was significantly deeper (p power levels.

  17. Oxidative burst-dependent NETosis is implicated in the resolution of necrosis-associated sterile inflammation

    Directory of Open Access Journals (Sweden)

    Mona Helena Biermann

    2016-12-01

    Full Text Available Necrosis is associated with a profound inflammatory response. The regulation of necrosis-associated inflammation, particularly the mechanisms responsible for resolution of inflammation are incompletely characterized. Nanoparticles are known to induce plasma membrane damage and necrosis followed by sterile inflammation. We observed that injection of metabolically inert nanodiamonds resulted in paw edema in WT and Ncf1** mice. However, while inflammation quickly resolved in WT mice, it persisted over several weeks in Ncf1** mice indicating failure of resolution of inflammation. Mechanistically, NOX2-dependent reactive oxygen species (ROS production and formation of neutrophil extracellular traps (NETs were essential for the resolution of necrosis-induced inflammation: Hence, by evaluating the fate of the particles at the site of inflammation, we observed that Ncf1** mice deficient in NADPH-dependent ROS failed to generate granulation tissue therefore being unable to trap the nanodiamonds. These data suggest that NOX2-dependent NETosis is crucial for preventing the chronification of the inflammatory response to tissue necrosis by forming NETosis-dependent barriers between the necrotic and healthy surrounding tissue.

  18. Root cause analysis of pump valve failures of three membrane pump systems

    NARCIS (Netherlands)

    Buijs, L.J.; Eijk, A.; Hooft, L. van

    2014-01-01

    This paper will present the root cause analysis and the solution of fatigue failures of the pump valves of three membrane pump systems installed on a chemical plant of Momentive in Pernis, the Netherlands. The membrane pumps were installed approximately 30 years ago. Each system has encountered

  19. Identification of Modeling Approaches To Support Common-Cause Failure Analysis

    International Nuclear Information System (INIS)

    Korsah, Kofi; Wood, Richard Thomas

    2015-01-01

    Experience with applying current guidance and practices for common-cause failure (CCF) mitigation to digital instrumentation and control (I&C) systems has proven problematic, and the regulatory environment has been unpredictable. The impact of CCF vulnerability is to inhibit I&C modernization and, thereby, challenge the long-term sustainability of existing plants. For new plants and advanced reactor concepts, the issue of CCF vulnerability for highly integrated digital I&C systems imposes a design burden resulting in higher costs and increased complexity. The regulatory uncertainty regarding which mitigation strategies are acceptable (e.g., what diversity is needed and how much is sufficient) drives designers to adopt complicated, costly solutions devised for existing plants. The conditions that constrain the transition to digital I&C technology by the U.S. nuclear industry require crosscutting research to resolve uncertainty, demonstrate necessary characteristics, and establish an objective basis for qualification of digital technology for usage in Nuclear Power Plant (NPP) I&C applications. To fulfill this research need, Oak Ridge National Laboratory is conducting an investigation into mitigation of CCF vulnerability for nuclear-qualified applications. The outcome of this research is expected to contribute to a fundamentally sound, comprehensive technical basis for establishing the qualification of digital technology for nuclear power applications. This report documents the investigation of modeling approaches for representing failure of I&C systems. Failure models are used when there is a need to analyze how the probability of success (or failure) of a system depends on the success (or failure) of individual elements. If these failure models are extensible to represent CCF, then they can be employed to support analysis of CCF vulnerabilities and mitigation strategies. Specifically, the research findings documented in this report identify modeling approaches that

  20. Identification of Modeling Approaches To Support Common-Cause Failure Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Korsah, Kofi [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wood, Richard Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-06-01

    Experience with applying current guidance and practices for common-cause failure (CCF) mitigation to digital instrumentation and control (I&C) systems has proven problematic, and the regulatory environment has been unpredictable. The impact of CCF vulnerability is to inhibit I&C modernization and, thereby, challenge the long-term sustainability of existing plants. For new plants and advanced reactor concepts, the issue of CCF vulnerability for highly integrated digital I&C systems imposes a design burden resulting in higher costs and increased complexity. The regulatory uncertainty regarding which mitigation strategies are acceptable (e.g., what diversity is needed and how much is sufficient) drives designers to adopt complicated, costly solutions devised for existing plants. The conditions that constrain the transition to digital I&C technology by the U.S. nuclear industry require crosscutting research to resolve uncertainty, demonstrate necessary characteristics, and establish an objective basis for qualification of digital technology for usage in Nuclear Power Plant (NPP) I&C applications. To fulfill this research need, Oak Ridge National Laboratory is conducting an investigation into mitigation of CCF vulnerability for nuclear-qualified applications. The outcome of this research is expected to contribute to a fundamentally sound, comprehensive technical basis for establishing the qualification of digital technology for nuclear power applications. This report documents the investigation of modeling approaches for representing failure of I&C systems. Failure models are used when there is a need to analyze how the probability of success (or failure) of a system depends on the success (or failure) of individual elements. If these failure models are extensible to represent CCF, then they can be employed to support analysis of CCF vulnerabilities and mitigation strategies. Specifically, the research findings documented in this report identify modeling approaches that

  1. Questioning the Role of Requirements Engineering in the Causes of Safety-Critical Software Failures

    Science.gov (United States)

    Johnson, C. W.; Holloway, C. M.

    2006-01-01

    Many software failures stem from inadequate requirements engineering. This view has been supported both by detailed accident investigations and by a number of empirical studies; however, such investigations can be misleading. It is often difficult to distinguish between failures in requirements engineering and problems elsewhere in the software development lifecycle. Further pitfalls arise from the assumption that inadequate requirements engineering is a cause of all software related accidents for which the system fails to meet its requirements. This paper identifies some of the problems that have arisen from an undue focus on the role of requirements engineering in the causes of major accidents. The intention is to provoke further debate within the emerging field of forensic software engineering.

  2. Bevacizumab as a treatment option for radiation-induced cerebral necrosis

    Energy Technology Data Exchange (ETDEWEB)

    Matuschek, Christiane; Boelke, Edwin; Budach, Wilfried [Univ. Hospital Duesseldorf (Germany). Dept. of Radiation Oncology; Nawatny, Jens [Univ. Hospital Duesseldorf (Germany). Dept. of Radiology; Hoffmann, Thomas K. [Duisburg-Essen Univ., Essen (Germany). Dept. of Otorhinolaryngology; Peiper, Matthias; Orth, Klaus [Hospital Essen-Sued, Essen (Germany). Dept. of Surgery; Gerber, Peter Arne [Univ. Hospital Duesseldorf (Germany). Dept. of Dermatology; Rusnak, Ethelyn [State Univ. of New York, Buffalo, NY (United States). Dept. of Anesthesiology; Lammering, Guido [Univ. Hospital Duesseldorf (Germany). Dept. of Radiation Oncology; MAASTRO Clinic, Maastricht (Netherlands). Radiation Oncology

    2011-02-15

    Radiation necrosis of normal CNS tissue represents one of the main risk factors of brain irradiation, occurring more frequently and earlier at higher total doses and higher doses per fraction. At present, it is believed that the necrosis results due to increasing capillary permeability caused by cytokine release leading to extracellular edema. This process is sustained by endothelial dysfunction, tissue hypoxia, and subsequent necrosis. Consequently, blocking the vascular endothelial growth factor (VEGF) at an early stage could be an option to reduce the development of radiation necrosis by decreasing the vascular permeability. This might help to reverse the pathological mechanisms, improve the symptoms and prevent further progression. A patient with radiation-induced necrosis was treated with an anti-VEGF antibody (bevacizumab), in whom neurologic signs and symptoms improved in accordance with a decrease in T1-weighted fluid-attenuated inversion recovery signals. Our case report together with the current literature suggests bevacizumab as a treatment option for patients with symptoms and radiological signs of cerebral necrosis induced by radiotherapy. (orig.)

  3. Bevacizumab as a treatment option for radiation-induced cerebral necrosis

    International Nuclear Information System (INIS)

    Matuschek, Christiane; Boelke, Edwin; Budach, Wilfried; Nawatny, Jens; Hoffmann, Thomas K.; Peiper, Matthias; Orth, Klaus; Gerber, Peter Arne; Rusnak, Ethelyn; Lammering, Guido; MAASTRO Clinic, Maastricht

    2011-01-01

    Radiation necrosis of normal CNS tissue represents one of the main risk factors of brain irradiation, occurring more frequently and earlier at higher total doses and higher doses per fraction. At present, it is believed that the necrosis results due to increasing capillary permeability caused by cytokine release leading to extracellular edema. This process is sustained by endothelial dysfunction, tissue hypoxia, and subsequent necrosis. Consequently, blocking the vascular endothelial growth factor (VEGF) at an early stage could be an option to reduce the development of radiation necrosis by decreasing the vascular permeability. This might help to reverse the pathological mechanisms, improve the symptoms and prevent further progression. A patient with radiation-induced necrosis was treated with an anti-VEGF antibody (bevacizumab), in whom neurologic signs and symptoms improved in accordance with a decrease in T1-weighted fluid-attenuated inversion recovery signals. Our case report together with the current literature suggests bevacizumab as a treatment option for patients with symptoms and radiological signs of cerebral necrosis induced by radiotherapy. (orig.)

  4. CSB-PGBD3 Mutations Cause Premature Ovarian Failure.

    Directory of Open Access Journals (Sweden)

    Yingying Qin

    2015-07-01

    Full Text Available Premature ovarian failure (POF is a rare, heterogeneous disorder characterized by cessation of menstruation occurring before the age of 40 years. Genetic etiology is responsible for perhaps 25% of cases, but most cases are sporadic and unexplained. In this study, through whole exome sequencing in a non-consanguineous family having four affected members with POF and Sanger sequencing in 432 sporadic cases, we identified three novel mutations in the fusion gene CSB-PGBD3. Subsequently functional studies suggest that mutated CSB-PGBD3 fusion protein was impaired in response to DNA damage, as indicated by delayed or absent recruitment to damaged sites. Our data provide the first evidence that mutations in the CSB-PGBD3 fusion protein can cause human disease, even in the presence of functional CSB, thus potentially explaining conservation of the fusion protein for 43 My since marmoset. The localization of the CSB-PGBD3 fusion protein to UVA-induced nuclear DNA repair foci further suggests that the CSB-PGBD3 fusion protein, like many other proteins that can cause POF, modulates or participates in DNA repair.

  5. Genetic and serological typing of European infectious haematopoietic necrosis virus (IHNV) isolates

    DEFF Research Database (Denmark)

    Johansson, Tove; Einer-Jensen, Katja; Batts, William

    2009-01-01

    Infectious haematopoietic necrosis virus (IHNV) causes the lethal disease infectious haematopoietic necrosis (IHN) in juvenile salmon and trout. The nucleocapsid (N) protein gene and partial glycoprotein (G) gene (nucleotides 457 to 1061) of the European isolates IT-217A, FR-32/87, DE-DF 13/98 11...

  6. Differential diagnosis of metastases in bone scans: chemotherapy induced bone necrosis

    International Nuclear Information System (INIS)

    Reuland, P.

    1999-01-01

    Aim: Influenced by the incorrect diagnosis of a bone metastasis caused by bone necrosis we evaluated reasons and frequency of bone necrosis in patients referred for bone scanning in follow-up of tumors. Methods: Bone scans performed within two years on patients with primary bone tumors or tumors metastatic to bone were reviewed in respect to the final diagnosis bone necrosis. Results: We found the cases of three young patients who presented the appearance of hot spots on bone scintigrams which were finally diagnosed as bone necrosis. In two cases the diagnosis was based on histological findings, in one case the diagnosis was made evident by follow-up. All the three patients had been treated by chemotherapy and presented no other reason for the development of bone necrosis. Enhanced tracer uptake in all sites decreased within eight weeks up to two years without therapy. Conclusion: Single and multiple hot spots after chemotherapy may be originated by bone necrosis but mimikry metastases. (orig.) [de

  7. Procedures for treating common cause failures in safety and reliability studies: Volume 2, Analytic background and techniques: Final report

    International Nuclear Information System (INIS)

    Mosleh, A.; Fleming, K.N.; Parry, G.W.; Paula, H.M.; Worledge, D.H.; Rasmuson, D.M.

    1988-12-01

    This report presents a framework for the inclusion of the impact of common cause failures in risk and reliability evaluations. Common cause failures are defined as that subset of dependent failures for which causes are not explicitly included in the logic model as basic events. The emphasis here is on providing procedures for a practical, systematic approach that can be used to perform and clearly document the analysis. The framework and the methods discussed for performing the different stages of the analysis integrate insights obtained from engineering assessments of the system and the historical evidence from multiple failure events into a systematic, reproducible, and defensible analysis. This document, Volume 2, contains a series of appendices that provide additional background and methodological detail on several important topics discussed in Volume 1

  8. Genome sequencing and transposon mutagenesis of Burkholderia seminalis TC3.4.2R3 identify genes contributing to suppression of orchid necrosis caused by B. gladioli

    Science.gov (United States)

    Thirty six strains of Burkholderia spp. isolated from sugarcane were evaluated for biological control of leaf and pseudobulb necrosis of orchid caused by B. gladioli. Twenty nine of the sugarcane strains suppressed the disease in greenhouse assays. We generated a draft genomic sequence of one suppr...

  9. Renal and post-renal causes of acute renal failure in children

    International Nuclear Information System (INIS)

    Jamal, A.; Ramzan, A.

    2004-01-01

    Objective: To identify the causes of acute renal failure (ARF) in pediatric population along with the identification of the age and gender most affected by the failure. Subjects and Methods: The study included children under the age of 12 years who presented with signs and symptoms suggestive of ARF (oliguria/anuria, vomiting, acidotic breathing etc.) along with raised blood urea nitrogen (BUN) serum creatinine and metabolic acidosis as shown by arterial blood gases (ABGs). Patients were divided into two group on the basis of age; group A consisting of 0-2 years and group B from >2 years. Patients presenting with transient pre-renal azotaemia were excluded from the study. After providing initial emergency cover, detailed history, physical examination and investigations were carried out according to a proforma specially designed to ascertain the cause of ARF. Patients were managed for ARF as per standard recommendations and investigations completed or repeated as and when required. Results: A total of 119 patients with ARF were admitted in the ward over a period of two years constituting 1.36% of the total admissions and 16.39% of the admissions due to renal pathology. Mean age of presentation was 4.5 years 16.7% of the patients under the age of 5 years. Male predominance was noted in all ages with an overall male to female ratio of 2.3:1. Most common cause leading to ARF in younger age group was found to be hemolytic uremic syndrome [25(54.34%)] followed by septicemia [7(15.21 %)]. In older patients renal calculus disease was the most common [22(30.13%)] underlying pathology followed by pre-existing, undiagnosed chronic renal failure [16(21.91 %)]. Conclusion: ARF is fairly cotton in children especially under the age of 5 years showing a male predominance. More than 90% of the cases can be prevented by improving primary health care and by early and prompt treatment of infections. (author)

  10. Avascular necrosis of bilateral femoral heads in a patient with Fabry's disease.

    LENUS (Irish Health Repository)

    O'Neill, Francis

    2012-07-13

    The underlying cause of avascular necrosis (AVN) of the femoral head is often not apparent. We report the case of a 26 year old builder with a four month history of bilateral hip pain, and a diagnosis of bilateral femoral head avascular necrosis. Fabry\\'s disease was identified as the probable cause. Since 2001, enzyme replacement therapy for Fabry\\'s disease has become available, with a potential to influence the disease process, and this is of potential importance to clinicians treating AVN.

  11. [The role of core decompression for the treatment of femoral head avascular necrosis in renal transplant recipients].

    Science.gov (United States)

    Zivcić-Cosić, Stela; Stalekar, Hrvoje; Mamula, Mihaela; Miletić, Damir; Orlić, Lidija; Racki, Sanjin; Cicvarić, Tedi

    2012-10-01

    Avascular bone necrosis is a relatively rare but significant complication in renal transplant recipients because it causes progressive pain and invalidity. It can be the consequence of the action of numerous causative factors, but it is mostly connected to corticosteroid treatment.The underlying pathophysiologic mechanism is a diminished blood flow to the bone leading to necrosis and bone destruction. During the past 25-years period, 570 renal transplantations and five combined kidney and pancreas transplantations were performed in our centre. A part of the patients was lost to follow-up due to the separation of Croatia from the former Republic of Yugoslavia. After transplantation, we revealed aseptic necrosis of the femoral head in five female patients. All patients had a history of treatment with pulse doses of corticosteroids. At transplantation the average age of the patients was 52.2 yrs (range 46 to 62 yrs), and dialytic treatment before transplantation lasted in average 9.2 yrs (range 2.5 to 21.2 yrs). The period between renal transplantation and the development of clinical signs of avascular bone necrosis lasted in average 1.2 yrs (range 0.3 to 2.3 yrs). We will demonstrate our 62-year old female patient with terminal renal failure caused by post-streptococcal glomerulonephritis, who was treated with peritoneal dialysis 2.5 years before renal transplantation. Twenty months before renal transplantation the patient received pulse doses of corticosteroids, together with immunoglobulins and plasmapheresis, for the treatment of an acute polyradiculoneuritis Guillaine Barré. After transplantation a standard immunosuppressive protocol was applied which included tacrolimus, mycophenolate mofetil, corticosteroids and induction with basiliximab. Four months after transplantation the patient started to feel pain in the right hip after longer standing, in addition to the earlier long-lasting problems caused by bilateral coxarthrosis. The pelvic radiograph showed

  12. Complex bladder-exstrophy-epispadias management: Causes of failure of initial bladder closure

    Directory of Open Access Journals (Sweden)

    Kouame Dibi Bertin

    2014-01-01

    Full Text Available The success of the initial closure of the complex bladder-exstrophy remains a challenge in pediatric surgery. This study describes a personal experience of the causes of failure of the initial closure and operative morbidity during the surgical treatment of bladder-exstrophy complex. From April 2000 to March 2014, four patients aged 16 days to 7 years and 5 months underwent complex exstrophy-epispadias repair with pelvic osteotomies. There were three males and one female. Three of them had posterior pelvic osteotomy, one had anterior innominate osteotomy. Bladder Closure: Bladder closure was performed in three layers. Our first patient had initial bladder closure with polyglactin 4/0 (Vicryl ® 4/0, concerning the last three patients, initial bladder closure was performed with polydioxanone 4/0 (PDS ® 4/0. The bladder was repaired leaving the urethral stent and ureteral stents for full urinary drainage for three patients. In one case, only urethral stent was left, ureteral drainage was not possible, because stents sizes were more important than the ureteral diameter. Out of a total of four patients, initial bladder closure was completely achieved for three patients. At the immediate postoperative follow-up, two patients presented a complete disunion of the abdominal wall and bladder despite an appropriate postoperative care. The absorbable braided silk (polyglactin used for the bladder closure was considered as the main factor in the failure of the bladder closure. The second cause of failure of the initial bladder closure was the incomplete urine drainage, ureteral catheterisation was not possible because the catheters sizes were too large compared with the diameters of the ureters. The failure of the initial bladder-exstrophy closure may be reduced by a closure with an absorbable monofilament silk and efficient urine drainage via ureteral catheterisation.

  13. Power distribution gradients in WWER type cores and fuel failure root causes

    Energy Technology Data Exchange (ETDEWEB)

    Mikuš, Ján M., E-mail: JanMikus.nrc@hotmail.com

    2014-02-15

    Highlights: • Power (fission rate) distribution gradients can represent fuel failure root causes. • Positions with above gradients were investigated in WWER type cores on reactor LR-0. • Above gradients were evaluated near core heterogeneities and construction materials. • Results can be used for code validation and fuel failure occurrence investigation. - Abstract: Neutron flux non-uniformity and gradients of neutron current resulting in corresponding power (fission rate) distribution changes can represent root causes of the fuel failure. Such situation can be expected in vicinity of some core heterogeneities and construction materials. Since needed data cannot be obtained from nuclear power plant (NPP), results of some benchmark type experiments performed on light water, zero-power research reactor LR-0 were used for investigation of the above phenomenon. Attention was focused on determination of the spatial power distribution changes in fuel assemblies (FAs): Containing fuel rods (FRs) with Gd burnable absorber in WWER-440 and WWER-1000 type cores, Neighboring the core blanket and dummy steel assembly simulators on the periphery of the WWER-440 standard and low leakage type cores, resp., Neighboring baffle in WWER-1000 type cores, and Neighboring control rod (CR) in WWER-440 type cores, namely (a) power peak in axial power distribution in periphery FRs of the adjacent FAs near the area between CR fuel part and butt joint to the CR absorbing part and (b) decrease in radial power distribution in FRs near CR absorbing part. An overview of relevant experimental results from reactor LR-0 and some information concerning leaking FAs on NPP Temelín are presented. Obtained data can be used for code validation and subsequently for the fuel failure occurrence investigation.

  14. Predictors of mortality and the provision of dialysis in patients with acute tubular necrosis. The Auriculin Anaritide Acute Renal Failure Study Group.

    Science.gov (United States)

    Chertow, G M; Lazarus, J M; Paganini, E P; Allgren, R L; Lafayette, R A; Sayegh, M H

    1998-04-01

    To explore the natural history of critically ill patients with acute renal failure due to acute tubular necrosis, we evaluated 256 patients enrolled in the placebo arm of a randomized clinical trial. Death and the composite outcome, death or the provision of dialysis, were determined with follow-up to 60 d. The relative risks (RR) and 95% confidence intervals (95% CI) associated with routinely available demographic, clinical, and laboratory variables were estimated using proportional hazards regression. Ninety-three (36%) deaths were documented; an additional 52 (20%) patients who survived received dialysis. Predictors of mortality included male gender (RR, 2.01; 95% CI, 1.21 to 3.36), oliguria (RR, 2.25; 95% CI, 1.43 to 3.55), mechanical ventilation (RR, 1.86; 95% CI, 1.18 to 2.93), acute myocardial infarction (RR, 3.14; 95% CI, 1.85 to 5.31), acute stroke or seizure (RR, 3.08; 95% CI, 1.56 to 6.06), chronic immunosuppression (RR, 2.37; 95% CI, 1.16 to 4.88), hyperbilirubinemia (RR, 1.06; 95% CI, 1.03 to 1.08 per 1 mg/dl increase in total bilirubin) and metabolic acidosis (RR, 0.95; 95% CI, 0.90 to 0.99 per 1 mEq/L increase in serum bicarbonate concentration). Predictors of death or the provision of dialysis were oliguria (RR, 5.95; 95% CI, 3.96 to 8.95), mechanical ventilation (RR, 1.53; 95% CI, 1.07 to 2.21), acute myocardial infarction (RR, 1.95; 95% CI, 1.24 to 3.07), arrhythmia (RR, 1.51; 95% CI, 1.04 to 2.19), and hypoalbuminemia (RR, 0.56; 95% CI, 0.42 to 0.74 per 1 g/dl increase in serum albumin concentration). Neither mortality nor the provision of dialysis was related to patient age. These observations can be used to estimate risk early in the course of acute tubular necrosis. Furthermore, these and related models may be used to adjust for case-mix variation in quality improvement efforts, and to objectively stratify patients in future intervention trials aimed at favorably altering the course of hospital-acquired acute renal failure.

  15. Fuel element failures caused by iodine stress corrosion

    International Nuclear Information System (INIS)

    Videm, K.; Lunde, L.

    1976-01-01

    Sections of unirradiated cladding tubes were plugged in both ends by mechanical seals and internally pressurized with argon containing iodine. The time to failure and the strain at failure as a function of stress was determined for tubing with different heat treatments. Fully annealed tubes suffer cracking at the lowest stress but exhibit the largest strains at failure. Elementary iodine is not necessary for stress corrosion: small amounts of iodides of zirconium, iron and aluminium can also give cracking. Moisture, however, was found to act as an inhibitor. A deformation threshold exists below which stress corrosion failure does not occur regardless of the exposure time. This deformation limit is lower the harder the tube. The deformation at failure is dependent on the deformation rate and has a minimum at 0.1%/hr. At higher deformation rates the failure deformation increases, but only slightly for hard tubes. Fuel was over-power tested at ramp rates varying between 0.26 to 30 W/cm min. For one series of fuel pins the failure deformations of 0.8% at high ramp rates were in good agreement with predictions based on stress corrosion experiments. For another series of experiments the failure deformation was surprisingly low, about 0.2%. (author)

  16. Investigating the Causes of Heart Failure based on Persian Medicine Point of View

    Directory of Open Access Journals (Sweden)

    R Ghods

    2017-07-01

    CONCLUSION: Several factors are mentioned as the cause of heart failure or heart weakness in PM, only a few of which are considered in modern medicine. However, some of these less considered theories can be used as new assumptions to prevent and control this disease

  17. Expanding arch aneurysm causing a "kink" in a Bentall graft and heart failure.

    Science.gov (United States)

    Al-Mohaissen, Maha A; Skarsgard, Peter; Khoo, Clarence; Virani, Sean A; Munt, Brad; Leipsic, Jonathon; Ignaszewski, Andrew

    2012-07-01

    Marfan syndrome is associated with a high incidence of aortic root aneurysm and life-threatening aortic dissection. With the successful use of surgical aortic root replacement, dissection-related mortality has been significantly reduced. We present the case of a patient with Marfan syndrome who presented with heart failure secondary to an unusual graft-related complication 14 years after a Bentall procedure. Investigations revealed a supra-aortic stenosis resulting from a kink in the Bentall graft caused by pressure from an expanding aortic arch aneurysm. The patient underwent surgery with improvement in his ejection fraction and heart failure symptoms.

  18. The difference in causes of early and late ultrafiltration failure in peritoneal dialysis

    NARCIS (Netherlands)

    Smit, Watske; Parikova, Alena; Struijk, Dirk G.; Krediet, Raymond T.

    2005-01-01

    OBJECTIVE: Ultrafiltration failure (UFF) is a major complication of peritoneal dialysis. Although it seems associated with long-term treatment, it can also occur in recently started patients. To identify the causes of this complication in patients with early and late UFF we studied a group of 48

  19. Star fruit (Averrhoa carambola) intoxication: an important cause of consciousness disturbance in patients with renal failure.

    Science.gov (United States)

    Chang, Chin-Tung; Chen, Yung-Chang; Fang, Ji-Tseng; Huang, Chiu-Ching

    2002-05-01

    Star fruit intoxication is a rare cause of consciousness disturbance in patients with renal failure. Most cases in the literature are uremic patients on maintenance dialysis. We present a patient with chronic renal failure, who was not on dialysis program yet, suffered from star fruit intoxication with presentation of consciousness disturbance and successfully managed by a session of hemodialysis.

  20. Bilateral streptococcal corneoscleritis complicating β irradiation induced scleral necrosis

    International Nuclear Information System (INIS)

    Moriarty, A.P.; Crawford, G.J.; McAllister, I.L.; Constable, I.J.

    1993-01-01

    Bacterial corneoscleritis may complicate scleral necrosis induced by β irradiation following pterygium removal. Previous cases have been unilateral. The authors report a case of severe bilateral corneoscleritis caused by Streptococcus pneumoniae. (author)

  1. Rin4 Causes Hybrid Necrosis and Race-Specific Resistance in an Interspecific Lettuce Hybrid

    NARCIS (Netherlands)

    Jeuken, M.J.W.; Zhang, N.; McHale, L.K.; Pelgrom, K.T.B.; Boer, den E.; Lindhout, P.; Michelmore, R.; Visser, R.G.F.; Niks, R.E.

    2009-01-01

    Some inter- and intraspecific crosses may result in reduced viability or sterility in the offspring, often due to genetic incompatibilities resulting from interactions between two or more loci. Hybrid necrosis is a postzygotic genetic incompatibility that is phenotypically manifested as necrotic

  2. Nephrotic Syndrome and Acute Renal Failure Apparently Induced by Sunitinib

    Directory of Open Access Journals (Sweden)

    Ying-Shou Chen

    2009-10-01

    Full Text Available We report a case of nephrotic syndrome and acute renal failure apparently induced by sunitinib. A 67-year-old man with a history of metastatic renal cell carcinoma presented with progressive kidney dysfunction with proteinuria, general edema, and body weight gain of 21 kg after undergoing 3 weeks of sunitinib therapy. The patient had taken no other over-the-counter medications, and all other possible causes of nephrotic syndrome were excluded. The Naranjo Adverse Drug Reaction Probability Scale score for this event was 6, indicating a high probability that the observed presentations were associated with use of the drug. However, despite the discontinuation of sunitinib, his condition deteriorated, and hemodialysis was initiated for respiratory distress. A renal biopsy was performed, which revealed ischemic acute tubular necrosis with minimal change nephropathy. In conclusion, nephrologists and oncologists should be aware that nephrotic syndrome with ischemic acute tubular necrosis is a possible adverse effect of sunitinib. For early diagnosis of this condition and to avoid renal damage, we recommend differential diagnosis of serum creatinine and proteinuria in patients undergoing sunitinib therapy.

  3. Cytokines and Organ Failure in Acute Pancreatitis

    DEFF Research Database (Denmark)

    Malmstrøm, Marie Louise; Hansen, Mark Berner; Andersen, Anders Møller

    2012-01-01

    Objectives: We aimed at synchronously examining the early time course of 4 proinflammatory cytokines as predictive factors for development of organ failure in patients with acute pancreatitis (AP). Methods: Interleukin (IL) 6, IL-8, IL-18, and tumor necrosis factor > were measured on admission...

  4. Renal papillary necrosis

    Science.gov (United States)

    ... asking your provider. Alternative Names Necrosis - renal papillae; Renal medullary necrosis Images Kidney anatomy Kidney - blood and urine flow References Bushinsky DA, Monk RD. Nephrolithiasis and nephrocalcinosis. ...

  5. Analysis approach for common cause failure on non-safety digital control system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yun Goo; Oh, Eungse [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of)

    2014-05-15

    The effects of common cause failure (CCF) on safety digital instrumentation and control (I and C) system had been considered in defense in depth and diversity coping analysis with safety analysis method. For the non-safety system, single failure had been considered for safety analysis. IEEE Std. 603-1991, Clause 5.6.3.1(2), 'Isolation' states that no credible failure on the non-safety side of an isolation device shall prevent any portion of a safety system from meeting its minimum performance requirements during and following any design basis event requiring that safety function. The software CCF is one of the credible failure on the non-safety side. In advanced digital I and C system, same hardware component is used for different control system and the defect in manufacture or common external event can generate CCF. Moreover, the non-safety I and C system uses complex software for its various function and software quality assurance for the development process is less severe than safety software for the cost effective design. Therefore the potential defects in software cannot be ignored and the effect of software CCF on non-safety I and C system is needed to be evaluated. This paper proposes the general process and considerations for the analysis of CCF on non-safety I and C system.

  6. Probabilistic common cause failure modeling for auxiliary feedwater system after the introduction of flood barriers

    International Nuclear Information System (INIS)

    Zheng, Xiaoyu; Yamaguchi, Akira; Takata, Takashi

    2013-01-01

    Causal inference is capable of assessing common cause failure (CCF) events from the viewpoint of causes' risk significance. Authors proposed the alpha decomposition method for probabilistic CCF analysis, in which the classical alpha factor model and causal inference are integrated to conduct a quantitative assessment of causes' CCF risk significance. The alpha decomposition method includes a hybrid Bayesian network for revealing the relationship between component failures and potential causes, and a regression model in which CCF parameters (global alpha factors) are expressed by explanatory variables (causes' occurrence frequencies) and parameters (decomposed alpha factors). This article applies this method and associated databases needed to predict CCF parameters of auxiliary feedwater (AFW) system when defense barriers against internal flood are introduced. There is scarce operation data for functionally modified safety systems and the utilization of generic CCF databases is of unknown uncertainty. The alpha decomposition method has the potential of analyzing the CCF risk of modified AFW system reasonably based on generic CCF databases. Moreover, the sources of uncertainty in parameter estimation can be studied. An example is presented to demonstrate the process of applying Bayesian inference in the alpha decomposition process. The results show that the system-specific posterior distributions for CCF parameters can be predicted. (author)

  7. Anastomoses of the Ovarian and Uterine Arteries: A Potential Pitfall and Cause of Failure of Uterine Embolization

    International Nuclear Information System (INIS)

    Matson, Matthew; Nicholson, Anthony; Belli, Anna-Maria

    2000-01-01

    Four women with symptomatic uterine fibroids were treated by uterine artery embolization (UAE). In all cases both uterine arteries were embolized via a single femoral puncture with polyvinyl alcohol using a selective catheter technique. In three cases, the ovarian artery was not visible on the initial angiogram before embolization, but appeared after the second uterine artery had been treated. In one case of clinical failure following UAE, a repeat angiogram demonstrated filling of the fibroids from the ovarian artery. Anastomoses between uterine and ovarian arteries may cause problems for radiologists performing UAE and are a potential cause of treatment failure

  8. Common cause failure and systems interactions issues - an overview

    International Nuclear Information System (INIS)

    Worledge, D.H.; Chu, B.B.; Conradi, L.L.; Smith, A.M.

    1985-01-01

    Common cause failures (CCFs) and systems interactions (SIs) are two concerns which have received significant attention over the years. Although many large and varied efforts have been directed toward these concerns, their resolution is less than satisfactory. Problems continue to exist, both in terms of understanding the basic issues represented by these concerns, and the perceived need for protection against their potentially harmful effects. This paper presents the results of recent EPRI work to provide a basis of understanding of these issues. Based on that improved understanding, a more appropriate way of defining and approaching the underlying technical questions is suggested. The current means of addressing the CCF and SI concerns are discussed and areas of additional activity needed to allow a more effective resolution are identified

  9. Galen's vein aneurysm as cause of heart failure

    International Nuclear Information System (INIS)

    Echeverria, Claudia; Cassalett, Gabriel; Franco, Jaime; Carrillo, Gustavo

    2005-01-01

    We present the case of a newborn admitted to the intensive care unit with a heart failure of difficult medical management. A large ductus arteriosus was found. It was surgically corrected, but the heart failure persisted and did not improve with medical treatment. Incidentally, a big Galen's vein aneurysm was found. Galen's vein aneurysm is a rare congenital pathology, originated by a fusion defect of the internal cerebral veins. Due to its low resistance, it produces a picture of high-output heart failure. Large defects may contain 50% to 60% of cardiac output. An aneurysm may be suspected in each newborn or infant with clinical picture of heart failure and right cardiac chamber dilation without any evidence of structural cardiac anomaly

  10. Risk factors of avascular necrosis of the femoral head and fixation failure in patients with valgus angulated femoral neck fractures over the age of 50 years.

    Science.gov (United States)

    Song, Hyung Keun; Choi, Ho June; Yang, Kyu Hyun

    2016-12-01

    The aim of our study was to identify the risk factors for avascular necrosis of the femoral head (AVN) and fixation failure (FF) after screw osteosynthesis in patients with valgus angulated femoral neck fractures. We conducted a retrospective study of 308 patients (mean age, 72.5 years, range, 50-97 years), with a mean follow-up of 21.4 months (range, 12-64 months). The risk for failure in treatment (FIT) associated with patient- and fracture-related factors was evaluated by logistic regression analyses. FIT was identified in 32 cases (10.3%): 22 cases (7.1%) of AVN and 10 cases (3.2%) of FF. Initial valgus tilt>15° (p=0.023), posterior tilt>15° (p=0.012), and screw sliding distance (p=0.037) were significantly associated with FIT. FIT occurred in 7 patients (5.2%) with B1.2.1 fractures and 17 patients (48.6%) with B1.1.2 fractures (p15° (B1.1.2) compared to patients with 15° are reasonable candidates for primary arthroplasty due to high risk of FIT. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Random safety auditing, root cause analysis, failure mode and effects analysis.

    Science.gov (United States)

    Ursprung, Robert; Gray, James

    2010-03-01

    Improving quality and safety in health care is a major concern for health care providers, the general public, and policy makers. Errors and quality issues are leading causes of morbidity and mortality across the health care industry. There is evidence that patients in the neonatal intensive care unit (NICU) are at high risk for serious medical errors. To facilitate compliance with safe practices, many institutions have established quality-assurance monitoring procedures. Three techniques that have been found useful in the health care setting are failure mode and effects analysis, root cause analysis, and random safety auditing. When used together, these techniques are effective tools for system analysis and redesign focused on providing safe delivery of care in the complex NICU system. Copyright 2010 Elsevier Inc. All rights reserved.

  12. Acute cardiac failure in neuroleptic malignant syndrome.

    LENUS (Irish Health Repository)

    Sparrow, Patrick

    2012-02-03

    We present a case of rapid onset acute cardiac failure developing as part of neuroleptic malignant syndrome in a 35-year-old woman following treatment with thioridazine and lithium. Post mortem histology of cardiac and skeletal muscle showed similar changes of focal cellular necrosis and vacuolation suggesting a common disease process.

  13. Presentation of common cause failures in fault tree structure of Krsko PSA : an historical overview

    International Nuclear Information System (INIS)

    Vrbanic, I.; Kosutic, I.; Vukovic, I.; Simic, Z.

    2003-01-01

    Failure of multiple components due to a common cause represents one of the most important issues in evaluation of system reliability or unavailability. The frequency of such events has relatively low expectancy, when compared to random failures, which affect individual components. However, in many cases the consequence is a direct loss of safety system or mitigative safety function. For this reason, the modeling of a common cause failure (CCF) and its presentation in fault tree structure is of the uttermost importance in probabilistic safety analyses (PSA). During the past decade, PSA model of Krsko NPP has undergone many small changes and a couple of major ones in fulfilling its basic purpose, which was serving as a tool for providing an appropriate information on the risk associated with actual plant design and operation. All changes to Krsko PSA model were undertaken in order to make it a better tool and / or to make it represent the plant in more accurate manner. The paper provides an overview of changes in CCF modeling in the fault tree structure from the initial PSA model development till present. (author)

  14. Delayed brain radiation necrosis: pathological review and new molecular targets for treatment.

    Science.gov (United States)

    Furuse, Motomasa; Nonoguchi, Naosuke; Kawabata, Shinji; Miyatake, Shin-Ichi; Kuroiwa, Toshihiko

    2015-12-01

    Delayed radiation necrosis is a well-known adverse event following radiotherapy for brain diseases and has been studied since the 1930s. The primary pathogenesis is thought to be the direct damage to endothelial and glial cells, particularly oligodendrocytes, which causes vascular hyalinization and demyelination. This primary pathology leads to tissue inflammation and ischemia, inducing various tissue protective responses including angiogenesis. Macrophages and lymphocytes then infiltrate the surrounding areas of necrosis, releasing inflammatory cytokines such as interleukin (IL)-1α, IL-6, and tumor necrosis factor (TNF)-α. Microglia also express these inflammatory cytokines. Reactive astrocytes play an important role in angiogenesis, expressing vascular endothelial growth factor (VEGF). Some chemokine networks, like the CXCL12/CXCR4 axis, are upregulated by tissue inflammation. Hypoxia may mediate the cell-cell interactions among reactive astrocytes, macrophages, and microglial cells around the necrotic core. Recently, bevacizumab, an anti-VEGF antibody, has demonstrated promising results as an alternative treatment for radiation necrosis. The importance of VEGF in the pathophysiology of brain radiation necrosis is being recognized. The discovery of new molecular targets could facilitate novel treatments for radiation necrosis. This literature review will focus on recent work characterizing delayed radiation necrosis in the brain.

  15. Airway necrosis after salvage esophagectomy

    International Nuclear Information System (INIS)

    Tanaka, Norimitsu; Hokamura, Nobukazu; Tachimori, Yuji

    2010-01-01

    Salvage esophagectomy is the sole curative intent treatment for patients with persistent or recurrent locoregional disease after definitive chemoradiotherapy (CRT) for esophageal carcinoma. However, salvage esophagectomy is a very high-risk operation, and airway necrosis is a fatal complication. Between 1997 and 2007, 49 patients with thoracic esophageal cancer underwent salvage esophagectomy after definitive CRT. We retrospectively compared patients with and without airway necrosis, and investigated operative procedures related to airway necrosis. Airway necrosis occurred in five patients (10.2%), of four patients (80%) died during their hospitalization. Airway necrosis seemed to be closely related to operative procedures, such as resection of bronchial artery and cervical and subcarinal lymph node dissection. Bronchogastric fistula following necrosis of gastric conduit occured in 2 patients reconstructed through posterior mediastinal route. Airway necrosis is a highly lethal complication after salvage esophagectomy. It is important in salvage esophagectomy to take airway blood supply into consideration sufficiently and to reconstruct through retrosternal route to prevent bronchogastric fistula. (author)

  16. Failure of azithromycin 2.0 g in the treatment of gonococcal urethritis caused by high-level resistance in California.

    Science.gov (United States)

    Gose, Severin O; Soge, Olusegun O; Beebe, James L; Nguyen, Duylinh; Stoltey, Juliet E; Bauer, Heidi M

    2015-05-01

    We report a treatment failure to azithromycin 2.0 g caused by a urethral Neisseria gonorrhoeae isolate with high-level azithromycin resistance in California. This report describes the epidemiological case investigation and phenotypic and genetic characterization of the treatment failure isolate.

  17. Common-cause failure analysis of McGuire Unit 2 auxiliary feedwater system

    International Nuclear Information System (INIS)

    Rasmuson, D.M.; Shepherd, J.C.; Fowler, R.D.; Summitt, R.L.; Logan, B.W.

    1982-01-01

    A powerful method for qualitative common cause failure analysis (CCFA) of nuclear power plant systems was developed by EG and G Idaho at the Idaho National Engineering Laboratory. As a cooperative project to demonstrate and evaluate the usefulness of the method, the Duke Power Company agreed to allow a CCFA of the auxiliary feedwater system (AFWS) in their McGuire Nuclear Station Unit 2. The results of the CCFA are the subject of this discussion

  18. Tumor necrosis factor in sepsis: mediator of multiple organ failure or essential part of host defense?

    NARCIS (Netherlands)

    van der Poll, T.; Lowry, S. F.

    1995-01-01

    Tumor necrosis factor-alpha (TNF) exerts numerous influences which, in association with severe infection, subserve both detrimental as well as beneficial host responses. The current review addresses recent insights into the structure and function of this pleiotropic cytokine, with a particular

  19. Causes of failure to control hypertension in people over 65 years of age

    Directory of Open Access Journals (Sweden)

    Alireza Khosravi

    2012-03-01

    Full Text Available BACKGROUND: Hypertension is a major cause of cardiovascular diseases whose prevalence increases by 10% for every 10 years after 50 years of age. This study aimed to investigate the causes of failure to control blood pressure in people aged over 65 years old. METHODS: This descriptive case-control study was conducted on 200 participants aged over 65 years old who were diagnosed with hypertension through a routine travel check-up for pilgrimage to Mecca in Amin Hospital, Isfahan, Iran during 2003. Following the medical examinations and blood pressure measurements according to the World Health Organization (WHO standards, the participants were divided into two groups of controlled blood pressure (case and uncontrolled blood pressure (control. A questionnaire was filled in for each participant and the data was analyzed using chi-square and student-t tests. RESULTS: The mean age was 70.7 ± 5.2 and 69 ± 4.9 in case and control groups, respectively. Less than half of the participants in the case group took anti-hypertensive medicine, out of which 87.5% were treated by a physician and 12.5% practiced self-therapy. In addition, 25% took their medicine regularly and 55% expressed a lack of motivation as the cause of discontinuing their medication. Furthermore, patients with controlled blood pressure had significantly better knowledge and performance than the case group (P < 0.05. CONCLUSION: The most common causes of failure to control blood pressure were poor knowledge, inappropriate practice in diet, stress, smoking, and irregular intake of medication. Keywords: Hypertension, Cardiovascular Diseases, Antihypertensive Agents, Diet Therapy    

  20. The Aznalcollar (Spain) tailings pond failure of 1998 and the ecological disaster of Guadiamar river: causes, effects and lessons

    International Nuclear Information System (INIS)

    Ayala-Carcedo, F. J.

    2004-01-01

    On 1998 a large tailings pond confined by a rock fill dyke in the Aznalcollar metallic mine near Sevilla, at the SW of Spain, failed with a big impact on public opinion due to potential environmental Impact on Donana National Park,a key natural space for birds migration between Europea and Africa. The accident is placed in a comparative way with others in the world, the causes of failure, its dynamics and the spill are analysed and also the actual ecological impacts related to the tailings and acid waters scattered by the Agrio and Guadiamar rivers. The lessons for future design and location of these type of deposits and water dams are also presented. The accident very quick, was caused by shear failure of the foundation formation, a miocene over consolidated marly clay, known as Guadalquivir blue marl, through a vertical point and a bedding plane, as a result of a progressive failure process under high pore pressure. Dynamic liquefaction of tailings due to sudden vertical movement towards the void created by the initial movement was a key factor to increase the outwards movement of the dyke, broken by the movement, and the tailings spill. The double dyke failure (main dyke and internal one) produced a tailings spill with solid and liquid flow. The dynamics of these flows is presented and also the combination of factors driving to failure. the problem posed by the successive human institutional failures, a necessary cause driving to no consideration of the possibility of the progressive failure in these formations, known from 1964, is also analysed. (Author) 67 refs

  1. Cerebral radiation necrosis: limits and prospects of experimental models

    International Nuclear Information System (INIS)

    Lefaix, J.L.

    1992-01-01

    Cerebral radiation necrosis is the major CNS hazard of clinical treatment therapy involving delivery of high doses of radiation to the brain. It is generally irreversible and frequently leads to death from brain necrosis. Necrosis has been reported with total doses of 60 Gy, delivered in conventional fractions. Symptoms depend upon the volume of brain irradiated and are frequently those of an intracranial mass and may be present as an area of gliosis or frank necrosis. Possible causes include some direct effect of radiation on glial cells, vascular changes and the action of an immunological mechanism. The weight of evidence suggests that demyelination is important in the early delayed reaction, and that vascular changes gradually become more important in the late delayed reactions, from several months to years after treatment. The advent of sophisticated radiographic technologies such as computed tomography, magnetic resonance imaging and spectroscopy, and positron emission tomography have facilitated serial non invasive examination of morphologic or physiologic parameters within the brain after irradiation. Limits and prospects of these technologies are reviewed in experimental animal models of late radiation injuries of the brain, which were carried out in many species ranging from mouse to monkey

  2. Study of the Atucha I nuclear power plant's residual heat removal system unavailability through the fault tree analysis and common cause failures

    International Nuclear Information System (INIS)

    Terrado, C.A.

    1991-06-01

    The present essay offers a comprehensive research of the Atucha I nuclear power plant's residual heat removal system unavailability, including Fault Tree Analysis and Common Cause Failures (CCF) treatment. The study is developed within the Event Tree perspective that considers the loss of external electrical power of the initiating event. The event was constructed by the Safety Evaluations Division of the Ezeiza Atomic Center in Argentina. According to the Event Tree, the research includes system demand during plant operation with 132 KV and emergency generation (Diesel motor generators). The system unavailability assessment is approached in two different ways: a) Considering independent failures only. b) Taking into account the existence of Common Cause Events, and modeling dependent failures. The Fault Tree quantification is played using the AIEA PSAPACK Code. The assessment data base is compiled from plant specific records and generic data bases like TECDOC 478. After Fault Tree model logic development, some general procedures used in common cause failures treating are applied to pick up another set of solutions. The results of the study are: a) Four Fault Trees have been developed to model the abovementioned system: 132 KV and emergency generation, both including and excluding CCF. b) The following unavailability values were obtained: 132 KV independent failures only: 7 10 -4 . Emergency generation independent failures only: 1.53 10 -2 . 132 KV dependent and independent failures: 3.6 10 -3 . Emergency generation dependent and independent failures: 1.74 10 -2 . The major conclusions obtained from the precedent results are: a) When using 132 KV system configuration, minimal cut sets involving common cause failures represents 81%from total system unavailability. b) The dependent failures treatment is an important task to be considered in safety assessments in order to reach more realistic values. (Author) [es

  3. Root cause analysis underscores the importance of understanding, addressing, and communicating cold chain equipment failures to improve equipment performance.

    Science.gov (United States)

    Lennon, Pat; Atuhaire, Brian; Yavari, Shahrzad; Sampath, Vidya; Mvundura, Mercy; Ramanathan, Nithya; Robertson, Joanie

    2017-04-19

    Vaccine cold chain equipment (CCE) in developing countries is often exposed to harsh environmental conditions, such as extreme temperatures and humidity, and is subject to many additional challenges, including intermittent power supply, insufficient maintenance capacity, and a scarcity of replacement parts. Together, these challenges lead to high failure rates for refrigerators, potentially damaging vaccines and adversely affecting immunization coverage. Providing a sustainable solution for improving CCE performance requires an understanding of the root causes of failure. Project teams conducted small-scale studies to determine the root causes of CCE failure in selected locations in Uganda and Mozambique. The evaluations covered 59 failed refrigerators and freezers in Uganda and 27 refrigerators in Mozambique. In Uganda, the vast majority of failures were due to a cooling unit fault in one widely used refrigerator model. In Mozambique, 11 of the 27 problems were attributable to solar refrigerators with batteries that were unable to hold a charge, and another eight problems were associated with a need to adjust thermostat settings. The studies showed that tracking and evaluation of equipment performance and failure can yield important, actionable information for a range of stakeholders, including local CCE technicians, the ministry of health, equipment manufacturers, and international partners such as the United Nations Children's Fund, World Health Organization, and Gavi, the Vaccine Alliance. Collaborative efforts to systematically collect and communicate data on CCE performance and causes of failure will help to improve the efficiency and reach of immunization programs in low- and middle-income countries. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  4. Non-compaction cardiomyopathy – an unusual cause of heart failure

    Directory of Open Access Journals (Sweden)

    Jure Dolenc

    2011-03-01

    Full Text Available Introduction: Non-compaction cardiomyopathy is a rare inborn anomaly caused by disorder of endomyocardial morphogenesis. The diagnosis is based on echocardiographic criteria. The prevalence in the adult population is not known. The symptoms are atypical. Three main groups of clinical signs exist: heart failure, thromobembolic events and arrhythmias. In the group of patients with reduced left ventricular function the prognosis is poor and the treatment options are limited. Patients and methods: In the recent 10 years, 7 patients with non-compaction cardiomyopathy were diagnosed at the Department of Cardiology of the University Medical Centre Ljubljana. Results: All seven patients were males, their mean age at the last follow-up being 39 ± 20.3 years (range 20 to 70 years. Five patients were diagnosed in adulthood. All of them fulfilled the echocardiographic diagnostic criteria of noncompaction cardiomyopathy. Five patients had depressed function of both ventricles, two patients had isolated left ventricular dysfunction. Three patients had decreased left ventricular ejection fraction, six patients showed left ventricular diastolic dysfunction. Only three patients had normal physical capacity. Two patients presented with clinical signs of overt heart failure. During follow-up, one patient died from heart failure. We observed thromboembolic events in one patient. Three patients suffered from nonsustained ventricular tachycardias and two patients had rhythm conduction abnormalities. Conclusions: Non-compaction cardiomyopathy is a rare disorder. We observed all common complications in our group of patients. The majority of patients displayed dysfunction of the affected ventricle and the dysfunction was more pronounced in older patients. Treatment of complications is an important factor in long-term survival of these patients.

  5. Operational Failures Caused by Arrogant Leaders

    National Research Council Canada - National Science Library

    Parrington, James R

    2008-01-01

    .... The failures of the Japanese and U.S. militaries directly resulted from the professional arrogance exhibited by Admiral Yamamoto and Secretary Rumsfeld as they deliberately limited the scope of their strategic thinking to how their...

  6. Cheyne-Stokes respiration in patients with congestive heart failure: causes and consequences

    OpenAIRE

    Lorenzi-Filho,Geraldo; Genta,Pedro R; Figueiredo,Adelaide C.; Inoue,Daniel

    2005-01-01

    Cheyne-Stokes respiration is a form of periodic breathing in which central apneas and hypopneas alternate with periods of hyperventilation, producing a waxing and waning pattern of tidal volume. This review focuses on the causes and consequences of Cheyne-Stokes respiration in patients with congestive heart failure, in whom the prevalence is strikingly high and ranges from 30% to 50%. Several factors have been implicated in the genesis of Cheyne-Stokes respiration, including low cardiac outpu...

  7. Sensitivity study of state-of-the-art common cause failure analysis

    International Nuclear Information System (INIS)

    Guey, Ching

    2004-01-01

    Common cause failures (CCFs) have been touted as one of the major contributors of plant risk due to its pervasive nature and somewhat conservative approaches taken in most Probabilistic Risk Assessment (PRA) studies. The objectives of this study are twofold: First, to gain a better understanding on the impact of various CCF failure probability on the overall plant risk. Secondly, to appreciate the state-of-the-art CCF modelling and data limitations for applications to a full-scale plant risk assessment. The sensitivity study of varying the CCF parameters for different cases indicates that CCF data differences based on the various cases commonly adopted in the PRAs yield core damage frequency variations between 8.5% to -25.6% of the baseline case. It appears that only if CCFs are guaranteed to occur, the core damage frequency would change significantly, by approximately a factor of 5. This suggests that prevention of CCFs is more important than dwelling on the analytical differences in the finer interpretation of the operating experience to develop the CCF parameters. (author)

  8. Drug immunogenicity in patients with inflammatory arthritis and secondary failure to tumour necrosis factor inhibitor therapies: the REASON study.

    Science.gov (United States)

    Balsa, Alejandro; Sanmarti, Raimon; Rosas, José; Martin, Victor; Cabez, Ana; Gómez, Susana; Montoro, María

    2018-04-01

    The aims were to evaluate the prevalence of anti-drug antibodies (ADA) in patients with RA or SpA experiencing secondary failure to anti-TNF therapy and to correlate ADA presence with anti-TNF concentration and clinical response. This was a cross-sectional, observational study of patients with active RA or SpA experiencing secondary failure to etanercept (ETN), infliximab (INF) or adalimumab (ADL). Concomitant non-biologic DMARDs were permitted. Serum anti-TNF and ADA levels were measured with two-site ELISA. Among 570 evaluable patients, those with RA (n = 276) were mostly female (80 vs 39%), older (56 vs 48 years), received concomitant DMARDs (83 vs 47%) and had maintained good clinical disease control for longer (202 vs 170 weeks) compared with patients with SpA (n = 294). ADA were found in 114/570 (20.0%) patients; 51/188 (27.1%) against INF and 63/217 (29.0%) against ADL; none against ETN. Of these 114 patients, 92 (81%) had no detectable serum drug concentrations. Proportionately more patients with SpA (31.3%) had anti-INF antibodies than those with RA (21.1%; P = 0.014). A significantly lower proportion of patients receiving concomitant DMARDs (16.5%) developed ADA than those on monotherapy (26.4%; P reasons for secondary treatment failure, but not the only one. Further investigations are needed to determine other causes of anti-TNF failure.

  9. Risk-based decision making to manage water quality failures caused by combined sewer overflows

    Science.gov (United States)

    Sriwastava, A. K.; Torres-Matallana, J. A.; Tait, S.; Schellart, A.

    2017-12-01

    Regulatory authorities set certain environmental permit for water utilities such that the combined sewer overflows (CSO) managed by these companies conform to the regulations. These utility companies face the risk of paying penalty or negative publicity in case they breach the environmental permit. These risks can be addressed by designing appropriate solutions such as investing in additional infrastructure which improve the system capacity and reduce the impact of CSO spills. The performance of these solutions is often estimated using urban drainage models. Hence, any uncertainty in these models can have a significant effect on the decision making process. This study outlines a risk-based decision making approach to address water quality failure caused by CSO spills. A calibrated lumped urban drainage model is used to simulate CSO spill quality in Haute-Sûre catchment in Luxembourg. Uncertainty in rainfall and model parameters is propagated through Monte Carlo simulations to quantify uncertainty in the concentration of ammonia in the CSO spill. A combination of decision alternatives such as the construction of a storage tank at the CSO and the reduction in the flow contribution of catchment surfaces are selected as planning measures to avoid the water quality failure. Failure is defined as exceedance of a concentration-duration based threshold based on Austrian emission standards for ammonia (De Toffol, 2006) with a certain frequency. For each decision alternative, uncertainty quantification results into a probability distribution of the number of annual CSO spill events which exceed the threshold. For each alternative, a buffered failure probability as defined in Rockafellar & Royset (2010), is estimated. Buffered failure probability (pbf) is a conservative estimate of failure probability (pf), however, unlike failure probability, it includes information about the upper tail of the distribution. A pareto-optimal set of solutions is obtained by performing mean

  10. Individualized monitoring of drug bioavailability and immunogenicity in rheumatoid arthritis patients treated with the tumor necrosis factor alpha inhibitor infliximab

    DEFF Research Database (Denmark)

    Bendtzen, Klaus; Geborek, Pierre; Svenson, Morten

    2006-01-01

    Infliximab, an anti-tumor necrosis factor alpha (anti-TNFalpha) antibody, is effective in the treatment of several immunoinflammatory diseases. However, many patients experience primary or secondary response failure, suggesting that individualization of treatment regimens may be beneficial...

  11. Correlation of MRI Biomarkers with Tumor Necrosis in Hras5 Tumor Xenograft in Athymic Rats

    Directory of Open Access Journals (Sweden)

    Daniel P. Bradley

    2007-05-01

    Full Text Available Magnetic resonance imaging (MRI can measure the effects of therapies targeting the tumor vasculature and has demonstrated that vascular-damaging agents (VDA induce acute vascular shutdown in tumors in human and animal models. However, at subtherapeutic doses, blood flow may recover before the induction of significant levels of necrosis. We present the relationship between changes in MRI biomarkers and tumor necrosis. Multiple MRI measurements were taken at 4.7 T in athymic rats (n = 24 bearing 1.94 ± 0.2-cm3 subcutaneous Hras5 tumors (ATCC 41000 before and 24 hours after clinically relevant doses of the VDA, ZD6126 (0-10 mg/kg, i.v.. We measured effective transverse relaxation rate (R2*, initial area under the gadolinium concentration-time curve (IAUGC60/150, equivalent enhancing fractions (EHF60/150, time constant (Ktrans, proportion of hypoperfused voxels as estimated from fit failures in Ktrans analysis, and signal intensity (SI in T2-weighted MRI (T2W. ZD6126 treatment induced < 90% dose-dependent tumor necrosis at 10 mg/kg; correspondingly, SI changes were evident from T2W MRI. Although R2* did not correlate, other MRI biomarkers significantly correlated with necrosis at doses of ≥ 5 mg/kg ZD6126. These data on Hras5 tumors suggest that the quantification of hypoperfused voxels might provide a useful biomarker of tumor necrosis.

  12. Causes and consequences of nonpersistence with heart failure medication.

    LENUS (Irish Health Repository)

    Mockler, Mary

    2012-02-01

    Persistence with therapy may be more easily and objectively identified in the clinical setting than compliance and recent work has shown it to be linked to mortality in heart failure (HF). The aim of this study was to determine the extent, causes, and clinical impact of nonpersistence with disease-modifying therapy in a retrospective cohort study of 183 patients with systolic HF participating in a disease management program. The main outcome measurements were reasons\\/determinants of nonpersistence and its impact on hospitalizations. Fifty-three patients (29%) had 74 separate occurrences of nonpersistence with disease-modifying therapy. There was no medical reason for discontinuing medications in 50% of occurrences, whereas medication was discontinued for an adverse reaction in 30% and for a justified medical reason in 15% of occurrences. Nonpersistence was a significant predictor of all-cause readmission (hazard ratio 3.20, 95% confidence interval 1.74 to 11.37) and cardiovascular readmission (hazard ratio 4.45, 95% confidence interval 1.74 to 11.37). In the adjusted model, there was no significantly increased risk of HF readmission (hazard ratio 2.41, 95% confidence interval 0.88 to 6.62). In conclusion, nonpersistence with HF therapy is common, is often not medically justified, and is associated with an increased risk of hospitalization.

  13. OECD/NEA International Common Cause Failure Data Exchange (ICDE) project - insights and lessons learnt

    International Nuclear Information System (INIS)

    Johanson, G.; Kreuser, A.; Pyy, P.; Rasmuson, D.; Werner, W.

    2006-01-01

    Events initiated by common-cause-failure (CCF) can significantly affect the availability and reliability of nuclear power plant safety systems. In recognition of this, CCF data are systematically collected and analysed in the International Common-Cause Data Exchange (ICDE) Project, which was initiated in August 1994. Since April 1998, the NEA has formally operated the project. Currently eleven countries participate in the project. The ICDE collects all events where two or more identical, redundant components of a group, fulfilling the same function, have failed or were impaired due to a shared cause (ICDE events). Complete CCFs, i. e. failure of all identical, redundant components in the group due to a shared cause are an important subset of the collected data. Currently, data exchange and analysis covers the following components: centrifugal pumps, diesel generators, motor-operated valves, safety and relief valves, check valves, reactor protection system components (level measurement, control rod drives, etc), circuit breakers, and batteries. The main findings of the ICDE reports issued by 2005 show averaged over all components that about two thirds of all complete CCF events involve faulty actions by plant personnel and contractors. The single largest contribution is from faulty testing and maintenance work due to deficient and/or incomplete procedures. Other important causes are insufficient testing and requalification of components or systems after maintenance, repair, modifications or backfitting work, as well as operator errors of commission. The probability that a reported ICDE event is a complete CCF decreases strongly with increasing number of redundant components, demonstrating the effectiveness of redundancy as a powerful defence against CCFs. However, complete CCFs cannot be completely prevented by high redundancy only. (orig.)

  14. Pathological investigation of radiation necrosis

    International Nuclear Information System (INIS)

    Nakamura, Nishio; Yoshimura, Noriaki; Ikuta, Fusahiro

    1975-01-01

    The brain and spinal cord of an 18-year-old male, who suffered from cerebellar medulloblastoma with subarachnoid spread, had been irradiated by a large amount of Linac X-ray: 14,450 rads to the lower thoracic segments and 7,400 rads to the lumbar segments. The tumor at the roof of the 4th ventricle had disseminated along the ventricular system but was limited to the subarachnoid space of the cervical spinal cord. No remarkable changes were found in the volume or consistency of the thoracic and lumbar cord. Elasticity of the lower thoracic segment was greatly diminished and the cut surfaces were yellowish white and fragile. Microscopically extensive coagulation necrosis was observed with complete disintegration of myelin and axon. Vascular changes were most prominent in the smaller vessels, eg. hyalinous thickening, concentric cleavage, adventitial fibrosis and edema of small artery perivascular spaces, fibrin thrombi occulusion of arterioles and capillaries, and telangiectasia. In the lumbar spinal cord, moderate neuronal degeneration and protoplasmic astrocytosis were observed. Changes in the lumbar posterior white column were considered to be not only secondary degeneration but also a primary lesion caused by irradiation. Liquefactive necrosis in the gray matter of the cervical cord was thought to be a nonspecific circulatory disturbance because of the absence of vascular changes. Vascular changes were thought to be very important in the histological diagnosis of radiation myelopathy and it was supposed that increased permeability of the vessel walls was a factor in coagulation necrosis. They considered this case to have typical histology of radiation myelopathy. (Evans, J.)

  15. [Avascular necrosis of the femoral head].

    Science.gov (United States)

    Porubský, Peter; Trč, Tomáš; Havlas, Vojtěch; Smetana, Pavel

    Avascular necrosis of the femoral head in adults is not common, but not too rare diseases. In orthopedic practice, it is one of the diseases that are causing implantation of hip replacement at a relatively early age. In the early detection and initiation of therapy can delay the implantation of prosthesis for several years, which is certainly more convenient for the patient and beneficial. This article is intended to acquaint the reader with the basic diagnostic procedures and therapy.

  16. Urinary creatinine to serum creatinine ratio and renal failure index in dogs infected with Babesia canis.

    Science.gov (United States)

    Zygner, Wojciech; Gójska-Zygner, Olga; Wesołowska, Agnieszka; Wędrychowicz, Halina

    2013-09-01

    Urinary creatinine to serum creatinine (UCr/SCr) ratio and renal failure index (RFI) are useful indices of renal damage. Both UCr/SCr ratio and RFI are used in differentiation between prerenal azotaemia and acute tubular necrosis. In this work the authors calculated the UCr/SCr ratio and RFI in dogs infected with Babesia canis and the values of these indices in azotaemic dogs infected with the parasite. The results of this study showed significantly lower UCr/SCr ratio in dogs infected with B. canis than in healthy dogs. Moreover, in azotaemic dogs infected with B. canis the UCr/SCr ratio was significantly lower and the RFI was significantly higher than in non-azotaemic dogs infected with B. canis. The calculated correlation between RFI and duration of the disease before diagnosis and treatment was high, positive and statistically significant (r = 0.89, p caused by B. canis in Poland acute tubular necrosis may develop.

  17. International common-cause failure data exchange. ICDE general coding guidelines - Technical note

    International Nuclear Information System (INIS)

    Johanson, Gunnar; Werner, Wolfgang; Concepcion Capote, Marina; Kreuser, Albert; Rasmuson, Dale; Jonsson, Esther; Pereira Pagan, Begona; Tirira, Jorge; Morris, Ian; Morales, Rosa; Oxberry, Anna; Kreuser, Albert

    2004-01-01

    Several Member countries of the Nuclear Energy Agency of the Organisation for Economic Co-operation and Development (OECD/NEA) have established the International Common-Cause Failure Data Exchange Project (ICDE Project) to encourage multilateral co-operation in the collection and analysis of data relating to Common-Cause Failure (CCF) events. The objectives of the ICDE Project are to: a) Collect and analyse CCF events over the long term so as to better understand such events, their causes, and their prevention; b) Generate qualitative insights into the root causes of CCF events which can then be used to derive approaches or mechanisms for their prevention or for mitigating their consequences; c) Establish a mechanism for the efficient feedback of experience gained in connection with CCF phenomena, including the development of defences against their occurrence, such as indicators for risk based inspections; and d) Record event attributes to facilitate quantification of CCF frequencies when so decided by the Project Working Group. The ICDE Project is envisaged to comprise all possible events of interest, including both complete and partial ICDE events. The ICDE Project will cover the key components of the main safety systems. Presently, the components listed below are included in the ICDE Project. Data have been collected for the six first components in the list: Centrifugal pumps, Diesel generators, Motor operated valves, Safety relief valves/power operated relief valves, Check valves, Batteries, Level measurement, Breakers, Control rod drive assemblies. Others will be added to this list later on. In this component coding guidelines, explanations on the ICDE General coding format are given. The guide reflects present experience with the data format and with the collected data. Further interpretations and clarifications will be added, should they become necessary. For each component analysed in the ICDE project, separate coding guidance is provided in the appendices

  18. Hypokalemic muscular paralysis causing acute respiratory failure due to rhabdomyolysis with renal tubular acidosis in a chronic glue sniffer.

    Science.gov (United States)

    Kao, K C; Tsai, Y H; Lin, M C; Huang, C C; Tsao, C Y; Chen, Y C

    2000-01-01

    A 34-year-old male was admitted to the emergency department with the development of quadriparesis and respiratory failure due to hypokalemia after prolonged glue sniffing. The patient was subsequently given mechanical ventilatory support for respiratory failure. He was weaned from the ventilator 4 days later after potassium replacement. Toluene is an aromatic hydrocarbon found in glues, cements, and solvents. It is known to be toxic to the nervous system, hematopoietic system, and causes acid-base and electrolyte disorders. Acute respiratory failure with hypokalemia and rhabdomyolysis with acute renal failure should be considered as potential events in a protracted glue sniffing.

  19. Acute liver failure caused by hepatitis E virus genotype 3 and 4: A systematic review and pooled analysis.

    Science.gov (United States)

    Haffar, Samir; Shalimar; Kaur, Ravinder J; Wang, Zhen; Prokop, Larry J; Murad, Mohammad H; Bazerbachi, Fateh

    2018-04-19

    Acute liver failure caused by hepatitis E virus genotype 3 and 4 has been rarely described. Because of the presence of a short golden therapeutic window in patients with viral acute liver failure from other causes, it is possible that early recognition and treatment might reduce the morbidity and mortality. We performed a systematic review and pooled analysis of acute liver failure caused by hepatitis E virus genotype 3 and 4. Two reviewers appraised studies after searching multiple databases on June 12th, 2017. Appropriate tests were used to compare hepatitis E virus genotype 3 vs 4, suspected vs confirmed genotypes, hepatitis E virus-RNA positive vs negative, and to discern important mortality risk factors. We identified 65 patients, with median age 58 years (range: 3-79), and a male to female ratio of 1.2:1. The median bilirubin, ALT, AST and alkaline phosphatase (expressed by multiplication of the upper limit of normal) levels were 14.8, 45.3, 34.8 and 1.63 respectively. Antihepatitis E virus IgG, antihepatitis E virus IgM and hepatitis E virus-RNA were positive in 84%, 91% and 86% of patients respectively. The median interval from symptoms onset to acute liver failure was 23 days, and 16 patients underwent liver transplantation. Final outcome was reported in 58 patients and mortality was 46%. Age was a predictor of poor prognosis in multivariate analysis. No important differences were found between patients infected with genotype 3 vs 4, patients with confirmed vs suspected genotypes, or patients with positive vs negative RNA. Acute liver failure caused by hepatitis E virus genotype 3 and 4 is rare, similar between genotypes, occurs commonly in middle-aged/elderly patients and has a very high mortality. Age is predictive of poor prognosis in multivariate analysis. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. External Dacryocystorhinostomy; Success Rate and Causes of Failure in Endoscopic and Pathologic Evaluations.

    Science.gov (United States)

    Ghasemi, Hassan; Asghari Asl, Sajedeh; Yarmohammadi, Mohammad Ebrahim; Jafari, Farhad; Izadi, Pupak

    2017-01-01

    External dacryocystorhinostomy (DCR) is the method of choice to treat nasolacrimal duct (NLD) obstruction and the other approaches are compared with it, with a failure rate of 4% to 13%. The current study aimed to assess the causes of failure in external DCR by postoperative endoscopic and pathological evaluation. The current retrospective cross sectional study followed-up113 patients with external DCR and silicone intubation for three months. Silicone tubes were removed after the third months. Failure was confirmed based on the clinical findings and irrigation test. Paranasal sinus computed tomography (CT) scanning, and endoscopic and pathological evaluations were performed in the failed cases. Totally, 113 patients underwent external DCR. The patients included 71 females and 42 males. The mean age of the patients was 55.91 years; ranged from 18 to 86. Epiphora was the most common complaint before surgery (90.3%). Clinically, epiphora continued in 17 cases (15%), of which 94.11% had at least one sinus CT abnormality and 82.35% had at least one endoscopic abnormality. The most common endoscopic findings were deviated septum (70.6%), scar tissue (52.94%), concha bullosa (46.9%), septal adhesion (47.05%), enlarged middle turbinate (41.2%), and sump syndrome (11.7%). The failure was significantly associated with the chronicity of the initial symptoms (P-value=0.00). Pathologically, there were significant relationship amongst the failure rate, scar formation, and allergic rhinitis (P-values =0.00 and <0.05, respectively). Preoperative endonasal evaluation and consultation with an otolaryngologist can improve surgical outcomes and help to have a better conscious to intranasal abnormalities before external DCR surgery.

  1. Successful Treatment of Anterior Tracheal Necrosis after Total Thyroidectomy Using Vacuum-Assisted Closure Therapy

    Directory of Open Access Journals (Sweden)

    Grégory Philippe

    2012-01-01

    Full Text Available Total thyroidectomy involving the adjacent structures of the trachea can cause tracheal damage such as early tracheal necrosis. The authors describe the first case of anterior tracheal necrosis following total thyroidectomy treated using vacuum-assisted closure device. After two weeks of VAC  therapy, there was no evidence of ongoing infection and the trachea was partially closed around a tracheotomy cannula, removed after 3 months. The use of a VAC  therapy to reduce and close the tracheal rent and to create a rapid granulation tissue over tracheal structure appeared as a good opportunity after anterior tracheal necrosis.

  2. United Kingdom nationwide study of avascular necrosis of the jaws including bisphosphonate-related necrosis.

    Science.gov (United States)

    Rogers, S N; Palmer, N O A; Lowe, D; Randall, C

    2015-02-01

    We aimed to record all new patients who presented to departments of oral surgery, oral medicine, and oral and maxillofacial surgery, and to dental hospitals in the UK, with avascular necrosis of the jaws including bisphosphonate-related necrosis (BRONJ) over a 2-year period (1 June 2009-31 May 2011). They were eligible irrespective of age, cause, or coexisting conditions. Data on incidence, clinical characteristics, risk factors, and coexisting conditions were collected. A total of 383 cases were registered: 369 were described as BRONJ, 5 as avascular necrosis, and 9 were unknown. Bisphosphonates had been given orally in 207 (56%), intravenously in 125 (34%), both orally and intravenously in 27 (7%), and was unknown in 9 (2%); one had been given denosumab. The main risk factor was dental extraction, and the mandible was commonly affected. The median duration of administration until onset of BRONJ was 3 years in those treated intravenously and 4 years in those treated orally. Levels of engagement with the study varied between regions, and extrapolation from the 2 most involved (Merseyside and Northern Ireland) found around 8.2-12.8 cases/million/year, which is 508-793 patients/year across the UK. To our knowledge this is one of the first studies to estimate national rates of BRONJ. It confirms that the risk and incidence are low. With changes in trends for antiresorptive bone medication, and increasing numbers of elderly people, it would be useful to repeat the registration in the future. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  3. Combinatorial analysis of systems with competing failures subject to failure isolation and propagation effects

    International Nuclear Information System (INIS)

    Xing Liudong; Levitin, Gregory

    2010-01-01

    This paper considers the reliability analysis of binary-state systems, subject to propagated failures with global effect, and failure isolation phenomena. Propagated failures with global effect are common-cause failures originated from a component of a system/subsystem causing the failure of the entire system/subsystem. Failure isolation occurs when the failure of one component (referred to as a trigger component) causes other components (referred to as dependent components) within the same system to become isolated from the system. On the one hand, failure isolation makes the isolated dependent components unusable; on the other hand, it prevents the propagation of failures originated from those dependent components. However, the failure isolation effect does not exist if failures originated in the dependent components already propagate globally before the trigger component fails. In other words, there exists a competition in the time domain between the failure of the trigger component that causes failure isolation and propagated failures originated from the dependent components. This paper presents a combinatorial method for the reliability analysis of systems subject to such competing propagated failures and failure isolation effect. Based on the total probability theorem, the proposed method is analytical, exact, and has no limitation on the type of time-to-failure distributions for the system components. An illustrative example is given to demonstrate the basics and advantages of the proposed method.

  4. rCBF in radiation necrosis as measured by xenon-enhanced CT

    International Nuclear Information System (INIS)

    Nakamura, Osamu; Nomura, Kazuhiro; Segawa, Hiromu; Nakagomi, Tadayoshi; Tanaka, Hideki; Yoshimasu, Norio; Takakura, Kintomo.

    1986-01-01

    We experienced a case of radiation necrosis in which the necrosis occurred two and a half years after radiation therapy against craniopharyngioma. In this case, we evaluated the regional cerebral blood flow (rCBF) by means of the Xe-enhanced CT method and studied the change in rCBF in comparison with the rCBF pattern of brain tumors or cerebral infarctions. In general, rCBF decreased in accordance with the low-density area in a conventional CT scan. The decrease in rCBF was most significant in the white matter, but the rCBF in the thinned cortex was also lowered. On the contrary, that of the basal ganglia was almost completely preserved. The rCBF pattern was different from those of brain tumors or diffuse cerebral infarction caused by the occlusion of the main arteries and was thought to be characteristic of radiation necrosis. Differential diagnosis between radiation necrosis and the recurrence of brain tumor has been thought to be difficult, but with this rCBF analysis the possibility of differential diagnosis between the two lesions was clearly indicated. (author)

  5. PHYSIOPATHOLOGY OF ACUTE RENAL FAILURE.NEW CLUES FOR AN OLD DILEMMA

    Directory of Open Access Journals (Sweden)

    Carlos G. Musso

    2008-01-01

    Full Text Available Acute renal failure (ARF is the term used to describe the sustained and abrupt reduction of the glomerular filtration, which causes the retention of waste products that come from the metabolism. Normally, the mechanisms potentially involved in ARF are divided into: pre-renal, parenchymatous, and post-renal. Regarding the etiology of the parenchymatous ARF, it would seem to be the sum of multiple pathogenic variables such as: tubular necrosis and apoptosis, alteration of the filtration barrier, retrodifusion of glomerular filtration, intrarenal vasoconstriction, contraction of the mesangium, intratubular obstruction, intersticial swelling, activation of proteolytic enzymes, and so on. Because of the above exposed data, only a multicausal perspective would seem to be adequate to understand and solve this syndrome.

  6. Programmed Necrosis: A Prominent Mechanism of Cell Death following Neonatal Brain Injury

    Directory of Open Access Journals (Sweden)

    Raul Chavez-Valdez

    2012-01-01

    Full Text Available Despite the introduction of therapeutic hypothermia, neonatal hypoxic ischemic (HI brain injury remains a common cause of developmental disability. Development of rational adjuvant therapies to hypothermia requires understanding of the pathways of cell death and survival modulated by HI. The conceptualization of the apoptosis-necrosis “continuum” in neonatal brain injury predicts mechanistic interactions between cell death and hydrid forms of cell death such as programmed or regulated necrosis. Many of the components of the signaling pathway regulating programmed necrosis have been studied previously in models of neonatal HI. In some of these investigations, they participate as part of the apoptotic pathways demonstrating clear overlap of programmed death pathways. Receptor interacting protein (RIP-1 is at the crossroads between types of cellular death and survival and RIP-1 kinase activity triggers formation of the necrosome (in complex with RIP-3 leading to programmed necrosis. Neuroprotection afforded by the blockade of RIP-1 kinase following neonatal HI suggests a role for programmed necrosis in the HI injury to the developing brain. Here, we briefly review the state of the knowledge about the mechanisms behind programmed necrosis in neonatal brain injury recognizing that a significant proportion of these data derive from experiments in cultured cell and some from in vivo adult animal models. There are still more questions than answers, yet the fascinating new perspectives provided by the understanding of programmed necrosis in the developing brain may lay the foundation for new therapies for neonatal HI.

  7. Maxillary Necrosis: A Sequelae of Fungal Osteomyelitis

    Directory of Open Access Journals (Sweden)

    K Anbarasi

    2010-01-01

    Full Text Available Osteomyelitis is designated to a variety of bone diseases having inflammation as a common denominator. Persistent infection progresses to inflammation of marrow space, haversian system and periostium of affected region. Thrombosis of endothelial vessels cause necrosis and sequestrum formation. Both pyogenic and nonpyogenic infections of jaw lead to this condition. Immunosuppressed patients are more prone to mycelial infections, whereas their occurrence in immunocompetent individuals are highly unusual.

  8. Inflammatory cascades driven by tumor necrosis factor-alpha play a major role in the progression of acute liver failure and its neurological complications.

    Directory of Open Access Journals (Sweden)

    Anne Chastre

    Full Text Available Acute liver failure (ALF due to ischemic or toxic liver injury is a clinical condition that results from massive loss of hepatocytes and may lead to hepatic encephalopathy (HE, a serious neuropsychiatric complication. Although increased expression of tumor necrosis factor-alpha (TNF-α in liver, plasma and brain has been observed, conflicting results exist concerning its roles in drug-induced liver injury and on the progression of HE. The present study aimed to investigate the therapeutic value of etanercept, a TNF-α neutralizing molecule, on the progression of liver injury and HE in mice with ALF resulting from azoxymethane (AOM hepatotoxicity.Mice were administered saline or etanercept (10 mg/kg; i.p. 30 minutes prior to, or up to 6 h after AOM. Etanercept-treated ALF mice were sacrificed in parallel with vehicle-treated comatose ALF mice and controls. AOM induced severe hepatic necrosis, leading to HE, and etanercept administered prior or up to 3 h after AOM significantly delayed the onset of coma stages of HE. Etanercept pretreatment attenuated AOM-induced liver injury, as assessed by histological examination, plasma ammonia and transaminase levels, and by hepatic glutathione content. Peripheral inflammation was significantly reduced by etanercept as shown by decreased plasma IL-6 (4.1-fold; p<0.001 and CD40L levels (3.7-fold; p<0.001 compared to saline-treated ALF mice. Etanercept also decreased IL-6 levels in brain (1.2-fold; p<0.05, attenuated microglial activation (assessed by OX-42 immunoreactivity, and increased brain glutathione concentrations.These results indicate that systemic sequestration of TNF-α attenuates both peripheral and cerebral inflammation leading to delayed progression of liver disease and HE in mice with ALF due to toxic liver injury. These results suggest that etanercept may provide a novel therapeutic approach for the management of ALF patients awaiting liver transplantation.

  9. Classic Bartter syndrome: a rare cause of failure to thrive in a child

    OpenAIRE

    Vieira, Helena; Mendes, Leonor; Mendes, Patricia; da Silva, José Esteves

    2012-01-01

    Bartter syndrome is a group of rare autosomal-recessive disorders caused by a defect in distal tubule transport of sodium and chloride. Blood gases and plasma electrolytes raise suspicion of this diagnosis and the definitive diagnosis is made by genetic study. Early treatment improves prognosis. The authors present the case of an 11-month-old child with early failure to thrive and severe regurgitation. Blood gases revealed hypochloraemic metabolic alkalosis, hyponatraemia and hypokalaemia. Bl...

  10. Reliability analysis of the auxiliary feedwater system of Angra-1 including common cause failures using the multiple greek letter model

    International Nuclear Information System (INIS)

    Lapa, Celso Marcelo Franklin.

    1996-05-01

    The use of redundancy to increase the reliability of industrial systems make them subject to the occurrence of common cause events. The industrial experience and the results of safety analysis studies have indicated that common cause failures are the main contributors to the unreliability of plants that have redundant systems, specially in nuclear power plants. In this Thesis procedures are developed in order to include the impact of common cause failures in the calculation of the top event occurrence probability of the Auxiliary Feedwater System in a typical two-loop Nuclear Power Plant (PWR). For this purpose the Multiple Greek Letter Model is used. (author). 14 refs., 10 figs., 11 tabs

  11. Avascular necrosis of femoral heads post-adrenal surgery for Cushing's syndrome: a rare presentation.

    LENUS (Irish Health Repository)

    2012-01-31

    Avascular necrosis (AVN) is a well-recognized complication of patients on high-dose steroids for a long time. Exogenous hypercortisolism is a well known cause of AVN and a number of cases have been reported. Cushing\\'s syndrome describes hypercortisolism of any cause endogenous or exogenous. A variety of traumatic and non-traumatic factors contribute to the aetiology of AVN although exogenous glucocorticoids administration and alcoholism are among the most common non-traumatic causes. AVN secondary to endogenous hypercortisolism is rare and very few case reports are available describing this complication. No literature is available on AVN presenting post-adrenal surgery. Here we present a young woman who presented with avascular necrosis of both hips 1 year after adrenalectomy for Cushing\\'s syndrome.

  12. Progressive skin necrosis of a huge occipital encephalocele

    Science.gov (United States)

    Andarabi, Yasir; Nejat, Farideh; El-Khashab, Mostafa

    2008-01-01

    Objects: Progressive skin necrosis of giant occipital encephalocoele is an extremely rare complication found in neonates. Infection and ulceration of the necrosed skin may lead to meningitis or sepsis. We present here a neonate with giant occipital encephalocoele showing progressive necrosis during the first day of his life. Methods: A newborn baby was found to have a huge mass in the occipital region, which was covered by normal pink-purplish skin. During the last hours of the first day of his life, the sac started becoming ulcerated accompanied with a rapid color change in the skin, gradually turning darker and then black. The neonate was taken up for urgent excision and repair of the encephalocele. Two years after the operation, he appears to be well-developed without any neurological problems. Conclusion: Necrosis may have resulted from arterial or venous compromise caused by torsion of the pedicle during delivery or after birth. The high pressure inside the sac associated with the thin skin of the encephalocoele may be another predisposing factor. In view of the risk of ulceration and subsequent infection, urgent surgery of the necrotizing encephalocele is suggested. PMID:19753210

  13. Progressive skin necrosis of a huge occipital encephalocele

    Directory of Open Access Journals (Sweden)

    Andarabi Yasir

    2008-01-01

    Full Text Available Objects: Progressive skin necrosis of giant occipital encephalocoele is an extremely rare complication found in neonates. Infection and ulceration of the necrosed skin may lead to meningitis or sepsis. We present here a neonate with giant occipital encephalocoele showing progressive necrosis during the first day of his life. Methods: A newborn baby was found to have a huge mass in the occipital region, which was covered by normal pink-purplish skin. During the last hours of the first day of his life, the sac started becoming ulcerated accompanied with a rapid color change in the skin, gradually turning darker and then black. The neonate was taken up for urgent excision and repair of the encephalocele. Two years after the operation, he appears to be well-developed without any neurological problems. Conclusion: Necrosis may have resulted from arterial or venous compromise caused by torsion of the pedicle during delivery or after birth. The high pressure inside the sac associated with the thin skin of the encephalocoele may be another predisposing factor. In view of the risk of ulceration and subsequent infection, urgent surgery of the necrotizing encephalocele is suggested.

  14. [Avascular necrosis of the femoral head in a patient with severe aplastic anaemia].

    Science.gov (United States)

    Plichta, Piotr; Pawelec, Katarzyna

    2011-01-01

    Avascular necrosis (AVN) is a pathological condition associated with numerous processes. Most frequent causes of ischaemia of the femoral head include trauma, corticosteroid therapy, radiation therapy, alcoholism, Gaucher's disease, systemic lupus erythematosus, rheumatoid arthritis. Corticosteroid therapy is considered the most frequent risk factor for developing avascular necrosis. In this paper we report a case of a 19-year old female patient who developed avascular necrosis of the right femoral head following treatment of severe aplastic anaemia. Clinical symptoms included groin pain and fever, painful abduction and internal rotation, tenderness over the right hip joint. The plain X-ray was not specific. However magnetic resonance imaging of the hip revealed changes characteristic for avascular necrosis. Conservative treatment was administrated. Two years after the onset of first clinical symptoms the patient is able to walk without pain, although the range of motion of the right hip joint is partially diminished. We evaluated the possible risk factors of AVN, diagnostic methods and prognosis. The onset of avascular necrosis should be considered as one of the relevant complications in patients with severe aplastic anaemia following immunosuppressive treatment.

  15. Usefulness of multimodality imaging for detection of myocardial infarction in patients with advanced kidney failure: case report

    Energy Technology Data Exchange (ETDEWEB)

    Veras, Mariana Ferreira; Azevedo, Jader Cunha de; Gamarski, Moisés; Mesquita, Evandro Tinoco; Mesquita, Cláudio Tinoco, E-mail: fvmari@gmail.com [Hospital Procardíaco, Rio de Janeiro, RJ (Brazil); Alves, José Galvão [Centro Universitário de Volta Redonda, RJ (Brazil)

    2016-01-15

    The third universal definition of acute myocardial infarction (AMI) is based on the elevation of troponin in association with ischemic symptoms, electrocardiographic changes and imaging findings. In patients with chest pain, the diagnosis of AMI is performed by dosing serum markers of myocardial necrosis, particularly troponins, by means of changes in 12 - lead electrocardiogram (ECG) or by identifying changes in the contractile dynamics of the left ventricle to the transthoracic echocardiogram. In some cases, confounding factors may hamper the diagnosis, such as: (a) presence of previous changes in the baseline ECG, especially LBBB; (b) elevations of myocardial necrosis markers (MNM) resulting from situations other than AMI and; (c) old changes in contractility detected by transthoracic ECG. Serum cardiac troponin (Tn) is the most specific and most used MNM for the diagnosis of AMI. Nevertheless, in some situations troponin elevation may not be due to an AMI, as in cases of acute pulmonary embolism, acute pericarditis, severe heart failure, myocarditis, and sepsis and kidney failure. Patients with kidney failure have high probability of concurrent cardiovascular disease. Furthermore, the cross-reacting proteins interfering with skeletal muscle, analytical imprecision and interactions with the dialysis membrane may cause elevation of troponin in 7% to 17% of patients with kidney failure. When in doubt about diagnosis of AMI, {sup 99m}Technetium pyrophosphate myocardial scintigraphy ({sup 99m}Tc-PYP) stands out as a noninvasive method capable of identifying areas of myocardial necrosis, thus helping in the diagnosis of AMI. {sup 99m}Tc-labeled phosphonate agents undergo chemical absorption with calcium. A large influx of calcium occurs during the evolutionary process of AMI. The calcium flows into the intracellular space and myocardial concentration of {sup 99m}Tc-PYP follows such increase, with a maximum peak uptake about 48 to 72 hours after the acute event. The

  16. Causes analysis on the failure of government environmental responsibility—Based on the perspective of law and economics

    Science.gov (United States)

    Fa, L. N.

    2017-11-01

    As the important Environmental Interests of Subjects, government behooves to undertake the corresponding responsibility of Pollution Control and Environmental Protection. The current situations in our country, however, appear as government environmental responsibility failure. Based on the analysis of law and economics, this article reaches the conclusion through game analysis, principle-agency relationship and utility theory that the prisoners dilemma of environmental interest game between government and enterprise, and the inherent defect of the principal-agency relationship between central government and local government are the inherent causes of government environmental responsibility failure. Many officials tends to graft and corrupt to maximum their own benefit, thus leading to the government failure among environmental pollution treatment and the environmental responsibility to undertake.

  17. Fulminant Hepatic Failure Attributed to Ackee Fruit Ingestion in a Patient with Sickle Cell Trait

    Directory of Open Access Journals (Sweden)

    Dianne E. Grunes

    2012-01-01

    Full Text Available We report a case of fulminant liver failure resulting in emergent liver transplantation following 3 weeks of nausea, vomiting, and malaise from Jamaican Vomiting Sickness. Jamaican Vomiting Sickness is caused by ingestion of the unripe arils of the Ackee fruit, its seeds and husks. It is characterized by acute gastrointestinal illness and hypoglycemia. In severe cases, central nervous system depression can occur. In previous studies, histologic sections taken from patients with Jamaican Vomiting Sickness have shown hepatotoxicity similar to that seen in Reye syndrome and/or acetaminophen toxicity. We highlight macroscopic and microscopic changes in the liver secondary to hepatoxicity of Ackee fruit versus those caused by a previously unknown sickle cell trait. We discuss the clinical variables and the synergistic hepatotoxic effect of Ackee fruit and ischemic injury from sickled red blood cells, causing massive hepatic necrosis in this patient.

  18. The standard deviation of extracellular water/intracellular water is associated with all-cause mortality and technique failure in peritoneal dialysis patients.

    Science.gov (United States)

    Tian, Jun-Ping; Wang, Hong; Du, Feng-He; Wang, Tao

    2016-09-01

    The mortality rate of peritoneal dialysis (PD) patients is still high, and the predicting factors for PD patient mortality remain to be determined. This study aimed to explore the relationship between the standard deviation (SD) of extracellular water/intracellular water (E/I) and all-cause mortality and technique failure in continuous ambulatory PD (CAPD) patients. All 152 patients came from the PD Center between January 1st 2006 and December 31st 2007. Clinical data and at least five-visit E/I ratio defined by bioelectrical impedance analysis were collected. The patients were followed up till December 31st 2010. The primary outcomes were death from any cause and technique failure. Kaplan-Meier analysis and Cox proportional hazards models were used to identify risk factors for mortality and technique failure in CAPD patients. All patients were followed up for 59.6 ± 23.0 months. The patients were divided into two groups according to their SD of E/I values: lower SD of E/I group (≤0.126) and higher SD of E/I group (>0.126). The patients with higher SD of E/I showed a higher all-cause mortality (log-rank χ (2) = 10.719, P = 0.001) and technique failure (log-rank χ (2) = 9.724, P = 0.002) than those with lower SD of E/I. Cox regression analysis found that SD of E/I independently predicted all-cause mortality (HR  3.551, 95 % CI 1.442-8.746, P = 0.006) and technique failure (HR  2.487, 95 % CI 1.093-5.659, P = 0.030) in CAPD patients after adjustment for confounders except when sensitive C-reactive protein was added into the model. The SD of E/I was a strong independent predictor of all-cause mortality and technique failure in CAPD patients.

  19. Common cause failure analysis of the rodded scram system of the Arkansas Nuclear One-Unit 1 Plant

    International Nuclear Information System (INIS)

    Montague, D.F.; Campbell, D.J.; Flanagan, G.F.

    1986-10-01

    This study demonstrates the use of a formal method for common cause failure analysis in a reliability analysis of the Arkansas Nuclear One - Unit 1 rodded scram system. The scram system failure of interest is loss of capability of the system to shut the reactor down when required. The results of this analysis support the ATWS program sponsored by the US Nuclear Regulatory Commission. The methods used in this analysis support the NRC's Risk Methods Integration and Evaluation Program (RMIEP)

  20. Classic Bartter syndrome: a rare cause of failure to thrive in a child.

    Science.gov (United States)

    Vieira, Helena; Mendes, Leonor; Mendes, Patricia; da Silva, José Esteves

    2012-06-28

    Bartter syndrome is a group of rare autosomal-recessive disorders caused by a defect in distal tubule transport of sodium and chloride. Blood gases and plasma electrolytes raise suspicion of this diagnosis and the definitive diagnosis is made by genetic study. Early treatment improves prognosis. The authors present the case of an 11-month-old child with early failure to thrive and severe regurgitation. Blood gases revealed hypochloraemic metabolic alkalosis, hyponatraemia and hypokalaemia. Blood pressure was normal and polyuria was documented. She began therapy with potassium chloride supplementation and indomethacin. There was clinical improvement and plasma potassium and bicarbonate normalised. The molecular study confirmed it was the classic form of Bartter syndrome. Despite being rare in clinical practice, which may lead to unnecessary medical investigation and diagnosis delay, in a child with failure to thrive, hypochloraemic metabolic alkalosis and hypokalaemia, this diagnosis must be considered.

  1. Analysis of the cause of failure in nonsurgical endodontic treatment by microscopic inspection during endodontic microsurgery.

    Science.gov (United States)

    Song, Minju; Kim, Hyeon-Cheol; Lee, Woocheol; Kim, Euiseong

    2011-11-01

    This study examined the clinical causes of failure and the limitation of a previous endodontic treatment by an inspection of the root apex and resected root surface at 26× magnification during endodontic microsurgery. The data were collected from patients in the Department of Conservative Dentistry at the Dental College, Yonsei University in Seoul, Korea between March 2001 and January 2011. All root-filled cases with symptomatic or asymptomatic apical periodontitis were enrolled in this study. All surgical procedures were performed by using an operating microscope. The surface of the apical root to be resected or the resected root surface after methylene blue staining was examined during the surgical procedure and recorded carefully with 26× magnification to determine the state of the previous endodontic treatment by using an operating microscope. Among the 557 cases with periapical surgery, 493 teeth were included in this study. With the exclusion of unknown cases, the most common possible cause of failure was perceived leakage around the canal filling material (30.4%), followed by a missing canal (19.7%), underfilling (14.2%), anatomical complexity (8.7%), overfilling (3.0%), iatrogenic problems (2.8%), apical calculus (1.8%), and cracks (1.2%). The frequency of possible failure causes differed according to the tooth position (P < .001). An appreciation of the root canal anatomy by using an operating microscope in nonsurgical endodontic treatment can make the prognosis more predictable and favorable. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. Skin Necrosis with Oculomotor Nerve Palsy Due to a Hyaluronic Acid Filler Injection

    Directory of Open Access Journals (Sweden)

    Jae Il Lee

    2017-07-01

    Full Text Available Performing rhinoplasty using filler injections, which improve facial wrinkles or soft tissues, is relatively inexpensive. However, intravascular filler injections can cause severe complications, such as skin necrosis and visual loss. We describe a case of blepharoptosis and skin necrosis caused by augmentation rhinoplasty and we discuss the patient’s clinical progress. We describe the case of a 25-year-old female patient who experienced severe pain, blepharoptosis, and decreased visual acuity immediately after receiving a filler injection. Our case suggests that surgeons should be aware of nasal vascularity before performing an operation, and that they should avoid injecting fillers at a high pressure and/or in excessive amounts. Additionally, filler injections should be stopped if the patient complains of severe pain, and appropriate measures should be taken to prevent complications caused by intravascular filler injections.

  3. Sedation for pediatric radiological procedures: analysis of potential causes of sedation failure and paradoxical reactions

    International Nuclear Information System (INIS)

    Karian, V.E.; Burrows, P.E.; Connor, L.; Zurakowski, D.; Mason, K.P.

    1999-01-01

    Background. Sedation for diagnostic imaging and interventional radiologic procedures in pediatrics has greatly increased over the past decade. With appropriate patient selection and monitoring, serious adverse effects are infrequent, but failure to sedate and paradoxical reactions do occur. Objective. The purpose of this study was to determine, among patients undergoing sedation for radiologic procedures, the incidence of sedation failure and paradoxical reaction to pentobarbital and to identify potentially correctable causes. Materials and methods. Records of 1665 patients who were sedated in the radiology department from 1 November 1997 to 1 July 1998 were reviewed. Patients failing sedation or experiencing paradoxical reaction were compared with respect to sex, age group, diagnosis, scan type, time of day, NPO status, use of IV contrast and type of sedation agent using the Fisher exact test, Pearson chi-square, analysis of variance (ANOVA), the Student t-test, and logistic regression. Results. Data analysis revealed a sedation failure rate of 1 % and paradoxical reaction rate of 1.2 %. Stepwise multiple logistic regression revealed that the only significant independent multivariate predictor of failure was the need for the administration of a combination of pentobarbital, fentanyl, and midazolam IV. Conclusion. The low rate of sedation failure and paradoxical reactions to pentobarbital was near optimal and probably cannot be improved with the currently available sedatives. (orig.)

  4. Sedation for pediatric radiological procedures: analysis of potential causes of sedation failure and paradoxical reactions

    Energy Technology Data Exchange (ETDEWEB)

    Karian, V.E.; Burrows, P.E.; Connor, L. [Dept. of Radiology, Children' s Hospital, Boston, MA (United States); Zurakowski, D. [Dept. of Biostatistics, Children' s Hospital, Boston, MA (United States); Mason, K.P. [Dept. of Anesthesiology, Children' s Hospital, Boston, MA (United States)

    1999-11-01

    Background. Sedation for diagnostic imaging and interventional radiologic procedures in pediatrics has greatly increased over the past decade. With appropriate patient selection and monitoring, serious adverse effects are infrequent, but failure to sedate and paradoxical reactions do occur. Objective. The purpose of this study was to determine, among patients undergoing sedation for radiologic procedures, the incidence of sedation failure and paradoxical reaction to pentobarbital and to identify potentially correctable causes. Materials and methods. Records of 1665 patients who were sedated in the radiology department from 1 November 1997 to 1 July 1998 were reviewed. Patients failing sedation or experiencing paradoxical reaction were compared with respect to sex, age group, diagnosis, scan type, time of day, NPO status, use of IV contrast and type of sedation agent using the Fisher exact test, Pearson chi-square, analysis of variance (ANOVA), the Student t-test, and logistic regression. Results. Data analysis revealed a sedation failure rate of 1 % and paradoxical reaction rate of 1.2 %. Stepwise multiple logistic regression revealed that the only significant independent multivariate predictor of failure was the need for the administration of a combination of pentobarbital, fentanyl, and midazolam IV. Conclusion. The low rate of sedation failure and paradoxical reactions to pentobarbital was near optimal and probably cannot be improved with the currently available sedatives. (orig.)

  5. Advanced Heart Failure

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Advanced Heart Failure Updated:May 9,2017 When heart failure (HF) ... Making This content was last reviewed May 2017. Heart Failure • Home • About Heart FailureCauses and Risks for ...

  6. Causes of failure with Szabo technique - an analysis of nine cases.

    Science.gov (United States)

    Jain, Rajendra Kumar; Padmanabhan, T N C; Chitnis, Nishad

    2013-01-01

    The objective of this case series is to identify and define causes of failure of Szabo technique in rapid-exchange monorail system for ostial lesions. From March 2009 to March 2011, 42 patients with an ostial lesion were treated percutaneously at our institution using Szabo technique in a monorail stent system. All patients received unfractionated heparin during intervention. Loading dose of clopidogrel, followed by clopidogrel and aspirin was administered. In 57% of patients, drug-eluting stents were used and in 42.8% patients bare metal stents. The stent was advanced over both wires, the target wire and the anchor wire. The anchor wire, which was passed through the proximal trailing strut of the stent helps to achieve precise stenting. The procedure was considered to be successful if stent was placed precisely covering the lesion and without stent loss or anchor wire prolapsing. Of the total 42 patients, the procedure was successful in 33, while failed in 9. Majority of failures were due to wire entanglement, which was fixed successfully in 3 cases by removing and reinserting the anchor wire. Out of other three failures, in one stent dislodgment occurred, stent could not cross the lesion in one and in another anchor wire got looped and prolapsed into target vessel. This case series shows that the Szabo technique, in spite of some difficulties like wire entanglement, stent dislodgement and resistance during stent advancement, is a simple and feasible method for treating variety of ostial lesions precisely compared to conventional angioplasty. Copyright © 2013 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

  7. Diversity Strategies to Mitigate Postulated Common Cause Failure Vulnerabilities

    International Nuclear Information System (INIS)

    Wood, Richard Thomas

    2010-01-01

    This paper describes an approach to establish effective mitigating strategies that can resolve potential common-cause failure (CCF) vulnerabilities in instrumentation and control (I and C) systems at nuclear power plants. A particular objective in the development of these strategies, which consist of combinations of diversity attributes and their associated criteria, is to address the unique characteristics of digital technology that can contribute to CCF concerns. The research approach employed to establish diversity strategies involves investigation of available documentation on diversity usage and experience from nuclear power and non-nuclear industries, capture of expert knowledge and lessons learned, determination of common practices, and assessment of the nature of CCFs and compensating diversity attributes. The resulting diversity strategies address considerations such as the effect of technology choices, the nature of CCF vulnerabilities, and the prospective impact of each diversity type. In particular, the impact of each attribute and criterion on the purpose, process, product, and performance aspects of diverse systems are considered.

  8. Acute renal failure requiring dialysis--a 5 year series.

    Science.gov (United States)

    Hooi, L S

    1997-09-01

    A retrospective review of 246 patients with established acute renal failure (ARF) needing dialysis from 1990-1994 is reported from Hospital Sultanah Aminah, Johor Bahru. Peritoneal dialysis was more commonly used than haemodialysis or haemofiltration. Patients on mechanical ventilation in Intensive Care Unit (ICU) who were hypercatabolic and fluid overloaded were treated with haemofiltration. Males outnumbered females by a ratio of 1.5:1. The majority were Malays (61.4%). Most patients were from the district of Johor Bahru, but 41.5% were from other districts in the Johor state. The mean age was 47.1 years (SD 18.2). The ARF was caused by acute tubular necrosis in 55.3%, post-renal obstruction in 22.8%, nephrotoxins in 5.7% and other causes in 16.2%. The proportions of patients referred from the medical, surgical and obstetric and gynaecology units were 50.8%, 45.5% and 3.7% respectively. The mortality rate was 48%. Patients with established ARF should be dialysed early as they tolerate uraemia poorly. Prevention is by prompt treatment of patients with sepsis, avoidance of hypovolaemia and nephrotoxic drugs.

  9. Targeting of regulated necrosis in kidney disease

    Directory of Open Access Journals (Sweden)

    Diego Martin-Sanchez

    2018-03-01

    Full Text Available The term acute tubular necrosis was thought to represent a misnomer derived from morphological studies of human necropsies and necrosis was thought to represent an unregulated passive form of cell death which was not amenable to therapeutic manipulation. Recent advances have improved our understanding of cell death in acute kidney injury. First, apoptosis results in cell loss, but does not trigger an inflammatory response. However, clumsy attempts at interfering with apoptosis (e.g. certain caspase inhibitors may trigger necrosis and, thus, inflammation-mediated kidney injury. Second, and most revolutionary, the concept of regulated necrosis emerged. Several modalities of regulated necrosis were described, such as necroptosis, ferroptosis, pyroptosis and mitochondria permeability transition regulated necrosis. Similar to apoptosis, regulated necrosis is modulated by specific molecules that behave as therapeutic targets. Contrary to apoptosis, regulated necrosis may be extremely pro-inflammatory and, importantly for kidney transplantation, immunogenic. Furthermore, regulated necrosis may trigger synchronized necrosis, in which all cells within a given tubule die in a synchronized manner. We now review the different modalities of regulated necrosis, the evidence for a role in diverse forms of kidney injury and the new opportunities for therapeutic intervention. Resumen: La idea de que el término necrosis tubular aguda supone una denominación inapropiada se deriva de estudios morfológicos de necropsias humanas. La opinión generalizada ha sido que la necrosis representa una forma pasiva de muerte celular no regulada que no es susceptible de manipulación terapéutica. Los recientes avances han mejorado nuestra comprensión de la muerte celular en la lesión renal aguda. En primer lugar, la apoptosis origina una pérdida celular, pero no desencadena una respuesta inflamatoria. Sin embargo, los intentos rudimentarios de interferir en la apoptosis

  10. Numerical modelling of solid transport caused by an extreme flood: Case of the Hamiz dam failure (Algeria

    Directory of Open Access Journals (Sweden)

    Haddad Ali

    2017-07-01

    Full Text Available Study of solid transport caused by the flow of an extreme flood such as the propagation of dam failure wave aims to simulate the hydrodynamics behaviour of the solid particles contained in the valley during the flood passage. With this intention, we have developed a numerical model which is based on the resolution of the one-dimensional Saint Venant–Exner equations by the implicit finite difference scheme. Numerical stability of liquid phase calculation is checked by the Courant number and De Vries condition for the solid phase. The model has been applied to the Hamiz dam (Algeria which is built in the semi arid zone and presents a major risk of failure. The simulation of several scenarios of dam failure has allowed us to trace the cartography of sediment transport in the valley which is induced by the flood of dam failure.

  11. Analysis of cause-specific failure endpoints using simple proportions: an example from a randomized controlled clinical trial in early breast cancer

    International Nuclear Information System (INIS)

    Panzarella, Tony; Meakin, J. William

    1998-01-01

    Purpose: To describe a statistically valid method for analyzing cause-specific failure data based on simple proportions, that is easy to understand and apply, and outline under what conditions its implementation is well-suited. Methods and Materials: In the comparison of treatment groups, time to first failure (in any site) was analyzed first, followed by an analysis of the pattern of first failure, preferably at the latest complete follow-up time common to each group. Results: A retrospective analysis of time to contralateral breast cancer in 777 early breast cancer patients was undertaken. Patients previously treated by mastectomy plus radiation therapy to the chest wall and regional nodal areas were randomized to receive further radiation and prednisone (R+P), radiation alone (R), or no further treatment (NT). Those randomized to R+P had a statistically significantly delayed time to first failure compared to the group randomized to NT (p = 0.0008). Patients randomized to R also experienced a delayed time to first failure compared to NT, but the difference was not statistically significant (p 0.14). At 14 years from the date of surgery (the latest common complete follow-up time) the distribution of first failures was statistically significantly different between R+P and NT (p = 0.005), but not between R and NT (p = 0.09). The contralateral breast cancer first failure rate at 14 years from surgery was 7.2% for NT, 4.6% for R, and 3.7% for R+P. The corresponding Kaplan-Meier estimates were 13.2%, 8.2%, and 5.4%, respectively. Conclusion: Analyzing cause-specific failure data using methods developed for survival endpoints is problematic. We encourage the use of the two-step analysis strategy described when, as in the example presented, competing causes of failure are not likely to be statistically independent, and when a treatment comparison at a single time-point is clinically relevant and feasible; that is, all patients have complete follow-up to this point

  12. Rooting out causes in failure analysis; Risk analysis

    Energy Technology Data Exchange (ETDEWEB)

    Keith, Graeme

    2010-07-01

    The Deepwater Horizon disaster was a terrible reminder of the consequences of equipment failure on facilities operating in challenging environments. Thankfully catastrophes on the scale of the Deepwater Horizon are rare, but equipment failure is a daily occurrence on installations around the globe. The consequences range from short unexpected downtime, to a total stop on production. from a brief burst of flaring to lasting environmental damage and from the momentary discomfiture of a worker to incapability or death. (Author)

  13. Taxonomy for Common-Cause Failure Vulnerability and Mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Richard Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Korsah, Kofi [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mullens, James Allen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pullum, Laura L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Applying current guidance and practices for common-cause failure (CCF) mitigation to digital instrumentation and control (I&C) systems has proven problematic, and the regulatory environment has been unpredictable. The potential for CCF vulnerability inhibits I&C modernization, thereby challenging the long-term sustainability of existing plants. For new plants and advanced reactor concepts, concern about CCF vulnerability in highly integrated digital I&C systems imposes a design burden that results in higher costs and increased complexity. The regulatory uncertainty in determining which mitigation strategies will be acceptable (e.g., what diversity is needed and how much is sufficient) drives designers to adopt complicated, costly solutions devised for existing plants. To address the conditions that constrain the transition to digital I&C technology by the US nuclear industry, crosscutting research is needed to resolve uncertainty, demonstrate necessary characteristics, and establish an objective basis for qualification of digital technology for nuclear power plant (NPP) I&C applications. To fulfill this research need, Oak Ridge National Laboratory is investigating mitigation of CCF vulnerability for nuclear-qualified applications. The outcome of this research is expected to contribute to a fundamentally sound, comprehensive basis to qualify digital technology for nuclear power applications. This report documents the development of a CCF taxonomy. The basis for the CCF taxonomy was generated by determining consistent terminology and establishing a classification approach. The terminology is based on definitions from standards, guides, and relevant nuclear power industry technical reports. The classification approach is derived from identified classification schemes focused on I&C systems and key characteristics, including failure modes. The CCF taxonomy provides the basis for a systematic organization of key systems aspects relevant to analyzing the potential for

  14. Heart Failure

    Science.gov (United States)

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...

  15. Delayed Recognition of Deterioration of Patients in General Wards Is Mostly Caused by Human Related Monitoring Failures: A Root Cause Analysis of Unplanned ICU Admissions.

    Directory of Open Access Journals (Sweden)

    Louise S van Galen

    Full Text Available An unplanned ICU admission of an inpatient is a serious adverse event (SAE. So far, no in depth-study has been performed to systematically analyse the root causes of unplanned ICU-admissions. The primary aim of this study was to identify the healthcare worker-, organisational-, technical,- disease- and patient- related causes that contribute to acute unplanned ICU admissions from general wards using a Root-Cause Analysis Tool called PRISMA-medical. Although a Track and Trigger System (MEWS was introduced in our hospital a few years ago, it was implemented without a clear protocol. Therefore, the secondary aim was to assess the adherence to a Track and Trigger system to identify deterioration on general hospital wards in patients eventually transferred to the ICU.Retrospective observational study in 49 consecutive adult patients acutely admitted to the Intensive Care Unit from a general nursing ward. 1. PRISMA-analysis on root causes of unplanned ICU admissions 2. Assessment of protocol adherence to the early warning score system.Out of 49 cases, 156 root causes were identified. The most frequent root causes were healthcare worker related (46%, which were mainly failures in monitoring the patient. They were followed by disease-related (45%, patient-related causes (7, 5%, and organisational root causes (3%. In only 40% of the patients vital parameters were monitored as was instructed by the doctor. 477 vital parameter sets were found in the 48 hours before ICU admission, in only 1% a correct MEWS was explicitly documented in the record.This in-depth analysis demonstrates that almost half of the unplanned ICU admissions from the general ward had healthcare worker related root causes, mostly due to monitoring failures in clinically deteriorating patients. In order to reduce unplanned ICU admissions, improving the monitoring of patients is therefore warranted.

  16. Electrical remodeling of cardiac myocytes from mice with heart failure due to the overexpression of tumor necrosis factor-alpha.

    Science.gov (United States)

    Petkova-Kirova, Polina S; Gursoy, Erdal; Mehdi, Haider; McTiernan, Charles F; London, Barry; Salama, Guy

    2006-05-01

    Mice that overexpress the inflammatory cytokine tumor necrosis factor-alpha in the heart (TNF mice) develop heart failure characterized by atrial and ventricular dilatation, decreased ejection fraction, atrial and ventricular arrhythmias, and increased mortality (males > females). Abnormalities in Ca2+ handling, prolonged action potential duration (APD), calcium alternans, and reentrant atrial and ventricular arrhythmias were previously observed with the use of optical mapping of perfused hearts from TNF mice. We therefore tested whether altered voltage-gated outward K+ and/or inward Ca2+ currents contribute to the altered action potential characteristics and the increased vulnerability to arrhythmias. Whole cell voltage-clamp recordings of K+ currents from left ventricular myocytes of TNF mice revealed an approximately 50% decrease in the rapidly activating, rapidly inactivating transient outward K+ current Ito and in the rapidly activating, slowly inactivating delayed rectifier current IK,slow1, an approximately 25% decrease in the rapidly activating, slowly inactivating delayed rectifier current IK,slow2, and no significant change in the steady-state current Iss compared with controls. Peak amplitudes and inactivation kinetics of the L-type Ca2+ current ICa,L were not altered. Western blot analyses revealed a reduction in the proteins underlying Kv4.2, Kv4.3, and Kv1.5. Thus decreased K+ channel expression is largely responsible for the prolonged APD in the TNF mice and may, along with abnormalities in Ca2+ handling, contribute to arrhythmias.

  17. When the heart kills the liver: acute liver failure in congestive heart failure

    Directory of Open Access Journals (Sweden)

    Saner FH

    2009-12-01

    Full Text Available Abstract Congestive heart failure as a cause of acute liver failure is rarely documented with only a few cases. Although the pathophysiology is poorly understood, there is rising evidence, that low cardiac output with consecutive reduction in hepatic blood flow is a main causing factor, rather than hypotension. In the setting of acute liver failure due to congestive heart failure, clinical signs of the latter can be absent, which requires an appropriate diagnostic approach. As a reference center for acute liver failure and liver transplantation we recorded from May 2003 to December 2007 202 admissions with the primary diagnoses acute liver failure. 13/202 was due to congestive heart failure, which was associated with a mortality rate of 54%. Leading cause of death was the underlying heart failure. Asparagine transaminase (AST, bilirubin, and international normalized ratio (INR did not differ significantly in surviving and deceased patients at admission. Despite both groups had signs of cardiogenic shock, the cardiac index (CI was significantly higher in the survival group on admission as compared with non-survivors (2.1 L/min/m2 vs. 1.6 L/min/m2, p = 0.04. Central venous - and pulmonary wedge pressure did not differ significantly. Remarkable improvement of liver function was recorded in the group, who recovered from cardiogenic shock. In conclusion, patients with acute liver failure require an appropriate diagnostic approach. Congestive heart failure should always be considered as a possible cause of acute liver failure.

  18. Intraperitoneal administration of high doses of polyethylene glycol (PEG) causes hepatic subcapsular necrosis and low-grade peritonitis with a rise in hepatic biomarkers

    International Nuclear Information System (INIS)

    Pellegrini, Giovanni; Starkey Lewis, Phil J.; Palmer, Luke; Hetzel, Udo; Goldring, Christopher E.; Park, B. Kevin; Kipar, Anja; Williams, Dominic P.

    2013-01-01

    Polyethylene glycols (PEGs) are commonly employed as excipients in preclinical studies and in vitro experiments to dissolve poorly hydrosoluble drugs. Their use is generally considered safe in both animals and humans; however, limited data is available concerning the safety of PEGs when administered parenterally. The results of our investigation demonstrate that PEG-400 can have an irritant effect on serosal surfaces and causes subcapsular hepatocellular necrosis in mice when administered intraperitoneally at a high dose (4 mL/kg). Accordingly, levels of serum biomarkers of liver injury need to be carefully interpreted in studies where PEG is administered intraperitoneally and always in association with the results of the histological assessment

  19. Ischemic necrosis and osteochondritis

    International Nuclear Information System (INIS)

    Weissman, S.D.

    1989-01-01

    Osteonecrosis indicates that ischemic death of the cellular constituents of bone and marrow has occurred. Historically, this first was thought to be related to sepsis in the osseous segments. However, continued studies led to the use of the term aseptic necrosis. Subsequent observations indicated that the necrotic areas of bone were not only aseptic, but were also avascular. This led to the terms ischemic necrosis, vascular necrosis and bone infarction. Ischemic necrosis of bone is discussed in this chapter. It results from a significant reduction in or obliteration of blood supply to the affected area. The various bone cells, including osteocytes, osteoclasts, and osteoblasts, usually undergo anoxic death in 12 to 48 hours after blood supply is cut off. The infarct that has thus developed in three-dimensional and can be divided into a number of zones: a central zone of cell death; an area of ischemic injury, most severe near the zone of cell death, and lessening as it moves peripherally; an area of active hyperemia and the zone of normal unaffected tissue. Once ischemic necrosis has begun, the cellular damage provokes an initial inflammatory response, which typically is characterized by vasodilatation, transudation of fluid and fibrin, and local infiltration of flammatory cells. This response can be considered the first stage in repair of the necrotic area

  20. Evaluation of Causes of Retaining Wall Failure

    Directory of Open Access Journals (Sweden)

    Mu'azu Mohammed ABDULLAHI

    2009-07-01

    Full Text Available Retaining structures are vital geotechnical structure, because the topography of the earth surface is a combination of plain, sloppy and undulating terrain. The retaining wall resists thrust of a bank of earth as well as providing soil stability of a change of ground elevation. Earth pressures on retaining wall are designed from theories of Soil Mechanics, but unfortunately the engineers using them do not always realize the significance of the assumption in their development. This is usually accompanied by with failure and partial failures because of designed based on rules and formulae that fit only limited conditions. In addition there are also problems of using bad backfill materials without taking precautionary measures against built–up of hydrostatic pressure by provision of drainage and also poor workmanship.

  1. Serum and Urinary Levels of Tumor Necrosis Factor-Alpha in Renal Transplant Patients.

    Science.gov (United States)

    Senturk Ciftci, Hayriye; Demir, Erol; Savran Karadeniz, Meltem; Tefik, Tzevat; Yazici, Halil; Nane, Ismet; Savran Oguz, Fatma; Aydin, Filiz; Turkmen, Aydin

    2017-12-18

    Allograft rejection is an important cause of early and long-term graft loss in kidney transplant recipients. Tumor necrosis factor-alpha promotes T-cell activation, the key reaction leading to allograft rejection. Here, we investigated whether serum and urinary tumor necrosis factor-alpha levels can predict allograft rejection. This study included 65 living related-donor renal transplant recipients with mean follow-up of 26 ± 9 months. Serum and urinary tumor necrosis factor-alpha levels were measured at pretransplant and at posttransplant time points (days 1 and 7 and months 3 and 6); serum creatinine levels were also monitored during posttransplant follow-up. Standard enzyme-linked immunoabsorbent assay was used to detect tumor necrosis factor-alpha levels. Clinical variables were monitored. Nine of 65 patients (13.8%) had biopsy-proven rejection during follow-up. Preoperative serum and urinary tumor necrosis factor-alpha levels were not significantly different when we compared patients with and without rejection. Serum tumor necrosis factor-alpha levels (in pg/mL) were significantly higher in the allograft rejection versus nonrejection group at day 7 (11.5 ± 4.7 vs 15.4 ± 5.8; P = .029) and month 1 (11.1 ± 4.8 vs 17.8 ± 10.9; P =.003). Urinary tumor necrosis factor-alpha levels (in pg/mL) were also elevated in the allograft rejection versus the nonrejection group at days 1 (10.2 ± 2.5 vs 14.1 ± 6.8; P = .002) and 7 (9.8 ± 2.2 vs 14.5 ± 2.7; P tumor necrosis factor-alpha has a role in diagnosing renal transplant rejection. Serum and urinary tumor necrosis factor-alpha levels may be a possible predictor for allograft rejection.

  2. Types of Heart Failure

    Science.gov (United States)

    ... Introduction Types of Heart Failure Classes of Heart Failure Heart Failure in Children Advanced Heart FailureCauses and ... and procedures related to heart disease and stroke. Heart Failure Questions to Ask Your Doctor Use these questions ...

  3. Two types of bone necrosis in the Middle Triassic Pistosaurus longaevus bones: the results of integrated studies

    Science.gov (United States)

    Surmik, Dawid; Rothschild, Bruce M.; Dulski, Mateusz; Janiszewska, Katarzyna

    2017-07-01

    Avascular necrosis, diagnosed on the basis of either a specific pathological modification of the articular surfaces of bone or its radiologic appearance in vertebral centra, has been recognized in many Mesozoic marine reptiles as well as in present-day marine mammals. Its presence in the zoological and paleontologic record is usually associated with decompression syndrome, a disease that affects secondarily aquatic vertebrates that could dive. Bone necrosis can also be caused by infectious processes, but it differs in appearance from decompression syndrome-associated aseptic necrosis. Herein, we report evidence of septic necrosis in the proximal articular surface of the femur of a marine reptile, Pistosaurus longaevus, from the Middle Triassic of Poland and Germany. This is the oldest recognition of septic necrosis associated with septic arthritis in the fossil record so far, and the mineralogical composition of pathologically altered bone is described herein in detail. The occurrence of septic necrosis is contrasted with decompression syndrome-associated avascular necrosis, also described in Pistosaurus longaevus bone from Middle Triassic of Germany.

  4. Classes of Heart Failure

    Science.gov (United States)

    ... Introduction Types of Heart Failure Classes of Heart Failure Heart Failure in Children Advanced Heart FailureCauses and ... and Advanced HF • Tools and Resources • Personal Stories Heart Failure Questions to Ask Your Doctor Use these questions ...

  5. International Common Cause Failure Data Exchange (ICDE). General Coding Guidelines - Updated Version, October 2011

    International Nuclear Information System (INIS)

    Johanson, Gunnar; Werner, Wolfgang; Capote, Marina Concepcion; Kreuser, Albert

    2012-01-01

    Several OECD/NEA member countries have established the International Common-Cause Failure Data Exchange Project ('ICDE Project') to encourage multilateral cooperation in the collection and analysis of data relating to Common-Cause Failure (CCF) events. The objectives of the ICDE Project are to: a) Collect and analyse CCF events over the long term so as to better understand such events, their causes, and their prevention. b) Generate qualitative insights into the root causes of CCF events which can then be used to derive approaches or mechanisms for their prevention or for mitigating their consequences. c) Establish a mechanism for the efficient feedback of experience gained in connection with CCF phenomena, including the development of defenses against their occurrence, such as indicators for risk based inspections. d) Record event attributes to facilitate quantification of CCF frequencies when so decided by the Project Working Group. The ICDE Project is envisaged to comprise all possible events of interest, including both complete and partial ICDE events. The ICDE Project will cover the key components of the main safety systems. Presently, the components listed below are included in the ICDE Project. Data have been collected for the six first components in the list: Centrifugal pumps, Diesel generators, Motor operated valves, Safety relief valves/power operated relief valves, Check valves, Batteries, Level measurement, Breakers, Control rod drive assemblies. Others will be added to this list later on. In this component coding guidelines, explanations on the ICDE general coding format are given. The guide reflects present experience with the data format and with the collected data. Further interpretations and clarifications will be added, should they become necessary. For each component analysed in the ICDE project, separate coding guidance is provided in the appendices ICDECG 01-06, specifying details relevant to the respective components

  6. Skin-Reducing Mastectomy in Immediate Reconstruction: How to Limit Complications and Failures.

    Science.gov (United States)

    Pechevy, Lolita; Carloni, Raphael; Guerid, Samia; Vincent, Pierre-Luc; Toussoun, Gilles; Delay, Emmanuel

    2017-06-01

    In hypertrophic and/or very ptotic breasts, skin-reducing mastectomy (SRM) is challenging and the risk of complications is high. Few publications have reported the use of an autologous latissimus dorsi flap (ALDF) in this indication. Most studies opt for implant reconstructions, with a high failure rate. We aimed to identify and present the technical refinements that reduce the risk of reconstruction failure in patients with hypertrophic and/or ptotic breasts with breast cancer or at risk of breast cancer after SRM with immediate breast reconstruction (IBR) utilizing an ALDF. Our retrospective study, covering a period of 18 years, included a series of 60 patients with hypertrophic and/or ptotic breasts who underwent 67 SRM and IBR procedures utilizing an ALDF. The complications were recorded and the risk factors analyzed. Sixty-seven SRMs were reviewed. Forty-nine procedures were performed with an inverted-T scar technique and 18 with a vertical scar technique. The nipple-areola complex (NAC) was preserved in 10 cases. There were eight (11.9%) cases of minor mastectomy flap necrosis after skin-reducing reconstructions, 16 (23.8%) wound dehiscences, no infections, no breast seromas, and no reconstruction failures. Smoking increased the risk of minor mastectomy flap necrosis (P = 0.048) and wound dehiscence (P = 0.002). Previous radiotherapy was associated with minor mastectomy flap necrosis (P = 0.001). The use of an ALDF together with technical refinements that preserve the vascular supply of the skin envelope leads to successful IBR with consistently good aesthetic results. Above all, it avoids failure of the reconstruction in very large or ptotic breasts. © 2017 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com

  7. Overview of management of acute renal failure and its evaluation; a case analysis

    Directory of Open Access Journals (Sweden)

    Nazar Chaudhary Muhammad Junaid

    2015-01-01

    Full Text Available The annual incidence is about 150 per million in the UK, but this figure is six times greater in the >80 years old group. Prerenal azotemia is considered as the most serious reason in community or hospital acquired acute renal failure (ARF. A 67-year-old middle age male was admitted to the hospital with a chief complaint of generalized weakness, volume depletion and dysuria. He has treated with metronidazole for diarrhoea caused by Clostridium difficile considered as the precipitating factor for the ARF. The patient has severe osteoarthritis and takes high dose non-steroidal anti-inflammatory drugs from the last two years. He also complains for obstructive sleep apnea (OSA and obesity. He has controlled hypertension was on lisinopril to control blood pressure. ARF is quite common, occurring in 80 million populations. Urinary obstruction should be excluded (a cause in around 5-10 of cases because this is readily reversible if it is diagnosed early. A renal US will be sufficient to identify obstruction in 95 of cases. Most cases of ARF are expected to pre renal failure/acute tubular necrosis (ATN 70-80%. Risk factor for development for at ATN are old age, drugs (non-steroidal anti-inflammatory drugs, gentamicin, sepsis, and chronic kidney disease and must be considered.

  8. Enteral feeding via jejunostomy as a cause of intestinal perforation and necrosis

    Directory of Open Access Journals (Sweden)

    María Victoria Vieiro-Medina

    Full Text Available Background: Jejunostomy for enteral feeding is excellent for patients who cannot manage oral intake, with a low complication rate. A Foley catheter, Ryle tube, Kerh tube or needle-catheter (Jejuno-Cath® are commonly used. It is a safe procedure but it can lead to severe complications. Case report: We present two cases: firstly, an 80 year old male who was admitted to the Emergency Room with a bowel perforation secondary to Jejuno-Cath® for enteral feeding after a subtotal gastrectomy with Roux-en-Y reconstruction; and secondly, a 53 year old male who was admitted to the Emergency Room due to gastric perforation developing multiple complications, including bowel necrosis and enteral feeding impaction. Discussion: We have reviewed the recent literature with regard to this rare complication.

  9. Colonic Necrosis in a 4-Year-Old with Hyperlipidemic Acute Pancreatitis

    Directory of Open Access Journals (Sweden)

    Tiffany J. Patton

    2016-01-01

    Full Text Available Here we report the case of a 4-year-old male with severe acute pancreatitis due to hyperlipidemia, who presented with abdominal pain, metabolic abnormalities, and colonic necrosis. This colonic complication was secondary to the extension of a large peripancreatic fluid collection causing direct serosal autodigestion by pancreatic enzymes. Two weeks following the initial presentation, the peripancreatic fluid collection developed into a mature pancreatic pseudocyst, which was percutaneously drained. To our knowledge, this is the youngest documented pediatric case of colonic necrosis due to severe pancreatitis and the first descriptive pediatric case of a colonic complication due to hyperlipidemia-induced acute pancreatitis.

  10. Causes of failure with Szabo technique – An analysis of nine cases

    Science.gov (United States)

    Jain, Rajendra Kumar; Padmanabhan, T.N.C.; Chitnis, Nishad

    2013-01-01

    Objective The objective of this case series is to identify and define causes of failure of Szabo technique in rapid-exchange monorail system for ostial lesions. Methods and results From March 2009 to March 2011, 42 patients with an ostial lesion were treated percutaneously at our institution using Szabo technique in a monorail stent system. All patients received unfractionated heparin during intervention. Loading dose of clopidogrel, followed by clopidogrel and aspirin was administered. In 57% of patients, drug-eluting stents were used and in 42.8% patients bare metal stents. The stent was advanced over both wires, the target wire and the anchor wire. The anchor wire, which was passed through the proximal trailing strut of the stent helps to achieve precise stenting. The procedure was considered to be successful if stent was placed precisely covering the lesion and without stent loss or anchor wire prolapsing. Of the total 42 patients, the procedure was successful in 33, while failed in 9. Majority of failures were due to wire entanglement, which was fixed successfully in 3 cases by removing and reinserting the anchor wire. Out of other three failures, in one stent dislodgment occurred, stent could not cross the lesion in one and in another anchor wire got looped and prolapsed into target vessel. Conclusion This case series shows that the Szabo technique, in spite of some difficulties like wire entanglement, stent dislodgement and resistance during stent advancement, is a simple and feasible method for treating variety of ostial lesions precisely compared to conventional angioplasty. PMID:23809379

  11. Regorafenib impairs mitochondrial functions, activates AMP-activated protein kinase, induces autophagy, and causes rat hepatocyte necrosis.

    Science.gov (United States)

    Weng, Zuquan; Luo, Yong; Yang, Xi; Greenhaw, James J; Li, Haibo; Xie, Liming; Mattes, William B; Shi, Qiang

    2015-01-02

    The tyrosine kinase inhibitor regorafenib was approved by regulatory agencies for cancer treatment, albeit with strong warnings of severe hepatotoxicity included in the product label. The basis of this toxicity is unknown; one possible mechanism, that of mitochondrial damage, was tested. In isolated rat liver mitochondria, regorafenib directly uncoupled oxidative phosphorylation (OXPHOS) and promoted calcium overload-induced swelling, which were respectively prevented by the recoupler 6-ketocholestanol (KC) and the mitochondrial permeability transition (MPT) pore blocker cyclosporine A (CsA). In primary hepatocytes, regorafenib uncoupled OXPHOS, disrupted mitochondrial inner membrane potential (MMP), and decreased cellular ATP at 1h, and triggered MPT at 3h, which was followed by necrosis but not apoptosis at 7h and 24h, all of which were abrogated by KC. The combination of the glycolysis enhancer fructose plus the mitochondrial ATPase synthase inhibitor oligomycin A abolished regorafenib induced necrosis at 7h. This effect was not seen at 24h nor with the fructose or oligomycin A separately. CsA in combination with trifluoperazine, both MPT blockers, showed similar effects. Two compensatory mechanisms, activation of AMP-activated protein kinase (AMPK) to ameliorate ATP shortage and induction of autophagy to remove dysfunctional mitochondria, were found to be mobilized. Hepatocyte necrosis was enhanced either by the AMPK inhibitor Compound C or the autophagy inhibitor chloroquine, while autophagy inducer rapamycin was strongly cytoprotective. Remarkably, all toxic effects were observed at clinically-relevant concentrations of 2.5-15μM. These data suggest that uncoupling of OXPHOS and the resulting ATP shortage and MPT induction are the key mechanisms for regorafenib induced hepatocyte injury, and AMPK activation and autophagy induction serve as pro-survival pathways against such toxicity. Published by Elsevier Ireland Ltd.

  12. Mycobacterium tuberculosis infection causes different levels of apoptosis and necrosis in human macrophages and alveolar epithelial cells.

    Science.gov (United States)

    Danelishvili, Lia; McGarvey, Jeffery; Li, Yong-Jun; Bermudez, Luiz E

    2003-09-01

    Mycobacterium tuberculosis interacts with macrophages and epithelial cells in the alveolar space of the lung, where it is able to invade and replicate in both cell types. M. tuberculosis-associated cytotoxicity to these cells has been well documented, but the mechanisms of host cell death are not well understood. We examined the induction of apoptosis and necrosis of human macrophages (U937) and type II alveolar epithelial cells (A549) by virulent (H37Rv) and attenuated (H37Ra) M. tuberculosis strains. Apoptosis was determined by both enzyme-linked immunosorbent assay (ELISA) and TdT-mediated dUTP nick end labelling (TUNEL) assay, whereas necrosis was evaluated by the release of lactate dehydrogenase (LDH). Both virulent and attenuated M. tuberculosis induced apoptosis in macrophages; however, the attenuated strain resulted in significantly more apoptosis than the virulent strain after 5 days of infection. In contrast, cytotoxicity of alveolar cells was the result of necrosis, but not apoptosis. Although infection with M. tuberculosis strains resulted in apoptosis of 14% of the cells on the monolayer, cell death associated with necrosis was observed in 59% of alveolar epithelial cells after 5 days of infection. Infection with M. tuberculosis suppressed apoptosis of alveolar epithelial cells induced by the kinase inhibitor, staurosporine. Because our findings suggest that M. tuberculosis can modulate the apoptotic response of macrophages and epithelial cells, we carried out an apoptosis pathway-specific cDNA microarray analysis of human macrophages and alveolar epithelial cells. Whereas the inhibitors of apoptosis, bcl-2 and Rb, were upregulated over 2.5-fold in infected (48 h) alveolar epithelial cells, the proapoptotic genes, bad and bax, were downregulated. The opposite was observed when U937 macrophages were infected with M. tuberculosis. Upon infection of alveolar epithelial cells with M. tuberculosis, the generation of apoptosis, as determined by the

  13. Data bank international of events of failure of common cause ICDE; Banco de datos internacional de sucesos de fallo de causa comum (ICDE)

    Energy Technology Data Exchange (ETDEWEB)

    Morales Castellanos, M. R.; Fernandez Andujar, B.; Pereira Pagan, M. B.

    2013-07-01

    Common Cause Failure (CCF) is a dependent event in which two or more components fail simultaneously or within a short space of time as a direct result of a shared common cause. Due to the low frequency of this type of events, some Member States of the Agency of Nuclear Energy (NEA) of the Organization for Cooperation and Economic Development (OECD) decided to create the project International Common-Cause Failure Data Exchange (ICDE) in order to encourage multilateral cooperation in the collection and analysis of data relating to CCF events.

  14. CCF-RBE common cause failure reliability benchmark exercise

    International Nuclear Information System (INIS)

    Poucet, A.; Amendola, A.; Cacciabue, P.C.

    1987-01-01

    This report summarizes results, obtained by the participants in the Reliability Benchmark Exercise on Common Cause Failures (CCF-RBE). The reference power plant of the CCF-RBE was the NPP at Grohnde (KWG): it is a 1300 MW PWR plant of KWU design and operated by the utility Preussen Elektra. The systems studied were the Start-up and Shut-down system (RR/RL) and the Emergency Feedwater System (RS) both systems that can feed water into the steam generators in the emergency power mode. The CCF-RBE was organized in two phases: 1. The first phase: during which all participants have performed an analysis on the complete system as defined by the assumed boundaries, i.e. the Start-up and Shut-down system (RR/RL) and the Emergency Feedwater System (RS). 2. The second phase: in which the scope was limited to the RS system. This limitation in scope was agreed upon in the discussion on the results of the first phase, which showed that, within the boundaries of the exercise, RR/RL and RS systems could be considered independent of each other. This report gives an overview of the works carried out, the results obtained and the conclusions and lessons that could be drawn from the CCF-RBE

  15. HIV reservoirs and immune surveillance evasion cause the failure of structured treatment interruptions: a computational study.

    Directory of Open Access Journals (Sweden)

    Emiliano Mancini

    Full Text Available Continuous antiretroviral therapy is currently the most effective way to treat HIV infection. Unstructured interruptions are quite common due to side effects and toxicity, among others, and cannot be prevented. Several attempts to structure these interruptions failed due to an increased morbidity compared to continuous treatment. The cause of this failure is poorly understood and often attributed to drug resistance. Here we show that structured treatment interruptions would fail regardless of the emergence of drug resistance. Our computational model of the HIV infection dynamics in lymphoid tissue inside lymph nodes, demonstrates that HIV reservoirs and evasion from immune surveillance themselves are sufficient to cause the failure of structured interruptions. We validate our model with data from a clinical trial and show that it is possible to optimize the schedule of interruptions to perform as well as the continuous treatment in the absence of drug resistance. Our methodology enables studying the problem of treatment optimization without having impact on human beings. We anticipate that it is feasible to steer new clinical trials using computational models.

  16. Superimposition of maximal stress and necrosis areas at the top of the femoral head in hip aseptic osteonecrosis.

    Science.gov (United States)

    Escudier, J-C; Ollivier, M; Donnez, M; Parratte, S; Lafforgue, P; Argenson, J-N

    2018-05-01

    Recent reports described possible mechanical factors in the development and aggravation of osteonecrosis of the femoral head (OFH), but these have yet to be confirmed on dedicated mechanical study. We therefore developed a 3D finite element model based on in-vivo data from patients with incipient OFH, with a view to determining whether the necrosis area was superimposed on the maximal stress area on the femoral head. The location of the necrosis area is determined by stress on the femoral head. All patients from the rheumatology department with early stage OFH in our center were investigated. Analysis of CT scans showed stress distribution on the head by 3D finite elements models, enabling determination of necrosis volume within the maximal stress area and of the percentage intersection of necrosis within the stress area (%I n/s: necrosis volume in stress area divided by total stress area volume and multiplied by 100) and of stress within the necrosis area (%I s/n: stress volume in necrosis area divided by total necrosis area volume and multiplied by 100). Nineteen of the 161 patients assessed retrospectively for the period between 2006 and 2015 had incipient unilateral OFH, 10 of whom (4 right, 6 left) had CT scans of sufficient quality for inclusion. Mean age was 52 years (range, 37-81 years). Mean maximal stress was 1.63MPa, mean maximal exported stress volume was 2,236.9 mm 3 and mean necrosis volume 6,291.1 mm 3 . Mean %I n/s was 83% and mean %I s/n 35%, with no significant differences according to gender, age, side or stress volume. There was a strong inverse correlation between necrosis volume and %I s/n (R 2 =-0.92) and a strong direct correlation between exported stress volume and %I s/n (R 2 =0.55). %I s/n was greater in small necrosis (stress area on the femoral head. The present results need confirmation by larger-scale studies. We consider it essential to take account of these mechanical parameters to reduce failure rates in conservative treatment of

  17. Dose and time relations in Hg(++)-induced tubular necrosis and regeneration

    DEFF Research Database (Denmark)

    Nielsen, J B; Andersen, H R; Andersen, O

    1994-01-01

    relationship is caused by a dose-related induction of kidney damage leading to increasing leakage of mercury through the kidneys. Histopathologic investigation revealed extensive necrosis of the proximal tubules in kidneys from mice exposed to 100 mumole HgCl2/kg or higher doses. Moreover, maximum renal damage...

  18. Genetic ablation of soluble tumor necrosis factor with preservation of membrane tumor necrosis factor is associated with neuroprotection after focal cerebral ischemia

    DEFF Research Database (Denmark)

    Madsen, Pernille M; Clausen, Bettina H; Degn, Matilda

    2016-01-01

    Microglia respond to focal cerebral ischemia by increasing their production of the neuromodulatory cytokine tumor necrosis factor, which exists both as membrane-anchored tumor necrosis factor and as cleaved soluble tumor necrosis factor forms. We previously demonstrated that tumor necrosis factor...... reduced infarct volumes at one and five days after stroke. This was associated with improved functional outcome after experimental stroke. No changes were found in the mRNA levels of tumor necrosis factor and tumor necrosis factor-related genes (TNFR1, TNFR2, TACE), pro-inflammatory cytokines (IL-1β, IL-6...... knockout mice display increased lesion volume after focal cerebral ischemia, suggesting that tumor necrosis factor is neuroprotective in experimental stroke. Here, we extend our studies to show that mice with intact membrane-anchored tumor necrosis factor, but no soluble tumor necrosis factor, display...

  19. Avascular Necrosis of the Capitate

    OpenAIRE

    Bekele, Wosen; Escobedo, Eva; Allen, Robert

    2011-01-01

    Avascular necrosis of the capitate is a rare entity. The most common reported etiology is trauma. We report a case of avascular necrosis of the capitate in a patient with chronic wrist pain that began after a single episode of remote trauma.

  20. False-positive breast screening due to fat necrosis following mammography

    International Nuclear Information System (INIS)

    Cawson, Jennifer N.; Malara, Frank A.

    2004-01-01

    Traumatic fat necrosis can result in a spectrum of imaging appearances that range from characteristically benign to those indistinguishable from malignancy. In such cases, biopsy might be required for diagnosis. The present case demonstrates a suspicious mammographic mass lesion appearing following a haematoma caused by a previous screening mammogram Copyright (2004) Blackwell Publishing Asia Pty Ltd

  1. SERCA2 Haploinsufficiency in a Mouse Model of Darier Disease Causes a Selective Predisposition to Heart Failure

    Directory of Open Access Journals (Sweden)

    Vikram Prasad

    2015-01-01

    Full Text Available Null mutations in one copy of ATP2A2, the gene encoding sarco/endoplasmic reticulum Ca2+-ATPase isoform 2 (SERCA2, cause Darier disease in humans, a skin condition involving keratinocytes. Cardiac function appears to be unimpaired in Darier disease patients, with no evidence that SERCA2 haploinsufficiency itself causes heart disease. However, SERCA2 deficiency is widely considered a contributing factor in heart failure. We therefore analyzed Atp2a2 heterozygous mice to determine whether SERCA2 haploinsufficiency can exacerbate specific heart disease conditions. Despite reduced SERCA2a levels in heart, Atp2a2 heterozygous mice resembled humans in exhibiting normal cardiac physiology. When subjected to hypothyroidism or crossed with a transgenic model of reduced myofibrillar Ca2+-sensitivity, SERCA2 deficiency caused no enhancement of the disease state. However, when combined with a transgenic model of increased myofibrillar Ca2+-sensitivity, SERCA2 haploinsufficiency caused rapid onset of hypertrophy, decompensation, and death. These effects were associated with reduced expression of the antiapoptotic Hax1, increased levels of the proapoptotic genes Chop and Casp12, and evidence of perturbations in energy metabolism. These data reveal myofibrillar Ca2+-sensitivity to be an important determinant of the cardiac effects of SERCA2 haploinsufficiency and raise the possibility that Darier disease patients are more susceptible to heart failure under certain conditions.

  2. Ketoconazole attenuates radiation-induction of tumor necrosis factor

    Energy Technology Data Exchange (ETDEWEB)

    Hallahan, D.E.; Virudachalam, S.; Kufe, D.W.; Weichselbaum, R.R. [Dana Farber Cancer Institute, Boston, MA (United States)

    1994-07-01

    Previous work has demonstrated that inhibitors of phospholipase A2 attenuate ionizing radiation-induced arachidonic acid production, protein kinase C activation, and prevent subsequent induction of the tumor necrosis factor gene. Because arachidonic acid contributes to radiation-induced tumor necrosis factor expression, the authors analyzed the effects of agents which alter arachidonate metabolism on the regulation of this gene. Phospholipase A2 inhibitors quinicrine, bromphenyl bromide, and pentoxyfylline or the inhibitor of lipoxygenase (ketoconazole) or the inhibitor of cycloxygenase (indomethacine) were added to cell culture 1 h prior to irradiation. Radiation-induced tumor necrosis factor gene expression was attenuated by each of the phospholipase A2 inhibitors (quinicrine, bromphenylbromide, and pentoxyfylline). Furthermore, ketoconazole attenuated X ray induced tumor necrosis factor gene expression. Conversely, indomethacin enhanced tumor necrosis factor expression following irradiation. The finding that radiation-induced tumor necrosis factor gene expression was attenuated by ketoconazole suggests that the lipoxygenase pathway participates in signal transduction preceding tumor necrosis factor induction. Enhancement of tumor necrosis factor expression by indomethacin following irradiation suggests that prostaglandins produced by cyclooxygenase act as negative regulators of tumor necrosis factor expression. Inhibitors of tumor necrosis factor induction ameliorate acute and subacute sequelae of radiotherapy. The authors propose therefore, that ketoconazole may reduce acute radiation sequelae such as mucositis and esophagitis through a reduction in tumor necrosis factor induction or inhibition of phospholipase A2 in addition to its antifungal activity. 25 refs., 2 figs.

  3. Avascular Necrosis of the Capitate

    Science.gov (United States)

    Bekele, Wosen; Escobedo, Eva; Allen, Robert

    2011-01-01

    Avascular necrosis of the capitate is a rare entity. The most common reported etiology is trauma. We report a case of avascular necrosis of the capitate in a patient with chronic wrist pain that began after a single episode of remote trauma. PMID:22470799

  4. Inhibition of the release of soluble tumor necrosis factor receptors in experimental endotoxemia by an anti-tumor necrosis factor-alpha antibody

    NARCIS (Netherlands)

    Jansen, J.; van der Poll, T.; Levi, M. [=Marcel M.; ten Cate, H.; Gallati, H.; ten Cate, J. W.; van Deventer, S. J.

    1995-01-01

    The role of tumor necrosis factor-alpha in the shedding of soluble tumor necrosis factor receptors in endotoxemia was investigated. The appearance of the soluble tumor necrosis factor receptors was assessed in four healthy volunteers following an intravenous injection of tumor necrosis factor-alpha

  5. Mortality Caused by Bath Exposure of Zebrafish (Danio rerio) Larvae to Nervous Necrosis Virus Is Limited to the Fourth Day Postfertilization.

    Science.gov (United States)

    Morick, Danny; Faigenbaum, Or; Smirnov, Margarita; Fellig, Yakov; Inbal, Adi; Kotler, Moshe

    2015-05-15

    Nervous necrosis virus (NNV) is a member of the Betanodavirus genus that causes fatal diseases in over 40 species of fish worldwide. Mortality among NNV-infected fish larvae is almost 100%. In order to elucidate the mechanisms responsible for the susceptibility of fish larvae to NNV, we exposed zebrafish larvae to NNV by bath immersion at 2, 4, 6, and 8 days postfertilization (dpf). Here, we demonstrate that developing zebrafish embryos are resistant to NNV at 2 dpf due to the protection afforded by the egg chorion and, to a lesser extent, by the perivitelline fluid. The zebrafish larvae succumbed to NNV infection during a narrow time window around the 4th dpf, while 6- and 8-day-old larvae were much less sensitive, with mortalities of 24% and 28%, respectively. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. NecroQuant: quantitative assessment of radiological necrosis

    Science.gov (United States)

    Hwang, Darryl H.; Mohamed, Passant; Varghese, Bino A.; Cen, Steven Y.; Duddalwar, Vinay

    2017-11-01

    Clinicians can now objectively quantify tumor necrosis by Hounsfield units and enhancement characteristics from multiphase contrast enhanced CT imaging. NecroQuant has been designed to work as part of a radiomics pipelines. The software is a departure from the conventional qualitative assessment of tumor necrosis, as it provides the user (radiologists and researchers) a simple interface to precisely and interactively define and measure necrosis in contrast-enhanced CT images. Although, the software is tested here on renal masses, it can be re-configured to assess tumor necrosis across variety of tumors from different body sites, providing a generalized, open, portable, and extensible quantitative analysis platform that is widely applicable across cancer types to quantify tumor necrosis.

  7. East coast fever caused by Theileria parva is characterized by macrophage activation associated with vasculitis and respiratory failure

    Science.gov (United States)

    Respiratory failure and death in East Coast Fever (ECF), a clinical syndrome of African cattle caused by the apicomplexan parasite Theileria parva, has historically been attributed to pulmonary infiltration by infected lymphocytes. However, immunohistochemical staining of tissue from T. parva infect...

  8. A Markov Model for Commen-Cause Failures

    DEFF Research Database (Denmark)

    Platz, Ole

    1984-01-01

    A continuous time four-state Markov chain is shown to cover several of the models that have been used for describing dependencies between failures of components in redundant systems. Among these are the models derived by Marshall and Olkin and by Freund and models for one-out-of-three and two...

  9. What caused the failures of the solenoid valve screws

    International Nuclear Information System (INIS)

    Vassallo, T.P.; Mumford, J.R.; Hossain, F.

    2001-01-01

    At Seabrook Station on May 5,1998 following a lengthy purge of the pressurizer steam space through Containment isolation sample valve 1-RC-FV-2830, the UL status light associated with this solenoid valve did not come on when the valve was closed from the plant's main control board. The UL status light is used to confirm valve closure position to satisfy the plant's Technical Specification requirements. The incorrect valve position indication on the main control board was initially believed to have resulted from excessive heat from a failed voltage control module that did not reduce the voltage to the valve's solenoid coil. This conclusion was based on a similar event that occurred in November of 1996. Follow-up in-plant testing of the valve determined that the voltage control module had not failed and was functioning satisfactorily. Subsequent investigations determined the root cause of the event to be excessive heat-up of the valve caused by high process fluid temperature and an excessively long purge of the pressurizer. The excessive heat-up of the valve from the high temperature process fluid weakened the magnetic field strength of the valve stem magnet to the extent that the UL status light reed switch would not actuate when the valve was closed. Since the voltage control module was tested and found to be functioning properly it was not replaced. Only the UL status light reed switch was replaced with a more sensitive reed that would respond better to a reduced magnetic field strength that results from a hot magnet. During reed switch replacement, three terminal block screws in the valve housing were found fractured and three other terminal block screws fractured during determination of the electrical conductors. This paper describes the initial plant event and ensuing laboratory tests and examinations that were performed to determine the root cause of the failure of the terminal block screws from the Containment isolation sample solenoid valve. (author)

  10. Programmed necrosis and necroptosis – molecular mechanisms

    Directory of Open Access Journals (Sweden)

    Agata Giżycka

    2015-12-01

    Full Text Available Programmed necrosis has been proven vital for organism development and homeostasis maintenance. Its regulatory effects on functional activity of the immune system, as well as on pathways regulating the death mechanisms in cells with diminished apoptotic activity, including malignant cells, have been confirmed. There is also increasing evidence indicating necrosis involvement in many human pathologies. Contrary to previous beliefs, necrosis is not only a passive, pathological, gene-independent process. However, the current knowledge regarding molecular regulation of programmed necrosis is scarce. In part this is due to the multiplicity and complexity of signaling pathways involved in programmed necrosis, as well as the absence of specific cellular markers identifying this process, but also the ambiguous and imprecise international terminology. This review presents the current state of the art on molecular mechanisms of programmed necrosis. In particular, its specific and frequent form, necroptosis, is discussed. The role of RIP1 and RIP3 kinases in this process is presented, as well as the diverse pathways induced by ligation of tumor necrosis factor α, to its receptor, TNFR1, i.e. cell survival, apoptosis or necroptosis.

  11. MerTK receptor cleavage promotes plaque necrosis and defective resolution in atherosclerosis

    NARCIS (Netherlands)

    Cai, Bishuang; Thorp, Edward B.; Doran, Amanda C.; Sansbury, Brian E.; Daemen, Mat J. A. P.; Dorweiler, Bernhard; Spite, Matthew; Fredman, Gabrielle; Tabas, Ira

    2017-01-01

    Atherothrombotic vascular disease is often triggered by a distinct type of atherosclerotic lesion that displays features of impaired inflammation resolution, notably a necrotic core and thinning of a protective fibrous cap that overlies the core. A key cause of plaque necrosis is defective clearance

  12. [Developmental radicular groove as a cause of endodontic failure].

    Science.gov (United States)

    Fabra Campos, H; Millet Part, J

    1989-01-01

    A clinical case of apical injury on an upper lateral incisor with endodontical and surgical failures in its treatment is presented. Extraction of the incisor and its study at the stereoscopic microscope showed the existence of a developmental groove running from the cingulum to the end of the root, establishing a communication between the crevice and the apical part of the tooth. Bacterial infection through the groove could provide an explanation for treatment failure.

  13. Heart failure - surgeries and devices

    Science.gov (United States)

    ... surgery; HF - surgery; Intra-aortic balloon pumps - heart failure; IABP - heart failure; Catheter based assist devices - heart failure ... problem may cause heart failure or make heart failure worse. Heart valve surgery may be needed to repair or ...

  14. Hyperbilirubinemia and rapid fatal hepatic failure in severe combined immunodeficiency caused by adenosine deaminase deficiency (ADA-SCID).

    Science.gov (United States)

    Kühl, J S; Schwarz, K; Münch, A; Schmugge, M; Pekrun, A; Meisel, C; Wahn, V; Ebell, W; von Bernuth, H

    2011-03-01

    Adenosin deaminase (ADA) deficiency is the cause for Severe Combined Immunodeficiency (SCID) in about 15% of patients with SCID, often presenting as T (-)B (-)NK (-)SCID. Treatment options for ADA-SCID are enzyme replacement, bone marrow transplantation or gene therapy. We here describe the first patient with ADA-SCID and fatal hepatic failure despite bone marrow transplantation from a 10/10 HLA identical related donor. As patients with ADA-SCID may be at yet underestimated increased risk for rapid hepatic failure we speculate whether hepatitis in ADA-SCID should lead to the immediate treatment with enzyme replacement by pegylated ADA. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Adenosine triphosphate hydrolysis reduces neutrophil infiltration and necrosis in partial-thickness scald burns in mice.

    Science.gov (United States)

    Bayliss, Jill; Delarosa, Sara; Wu, Jianfeng; Peterson, Jonathan R; Eboda, Oluwatobi N; Su, Grace L; Hemmila, Mark; Krebsbach, Paul H; Cederna, Paul S; Wang, Stewart C; Xi, Chuanwu; Levi, Benjamin

    2014-01-01

    Extracellular adenosine triphosphate (ATP), present in thermally injured tissue, modulates the inflammatory response and causes significant tissue damage. The authors hypothesize that neutrophil infiltration and ensuing tissue necrosis would be mitigated by removing ATP-dependent signaling at the burn site. Mice were subjected to 30% TBSA partial-thickness scald burn by dorsal skin immersion in a water bath at 60 or 20°C (nonburn controls). In the treatment arm, an ATP hydrolyzing enzyme, apyrase, was applied directly to the site immediately after injury. Skin was harvested after 24 hours and 5 days for hematoxylin and eosin stain, elastase, and Ki-67 staining. Tumor necrosis factor (TNF)-α and interferon (IFN)-β expression were measured through quantitative real-time polymerase chain reaction. At 24 hours, the amount of neutrophil infiltration was different between the burn and burn + apyrase groups (P burn group at 24 hours and 5 days. TNF-α and IFN-β expression at 24 hours in the apyrase group was lower than in the burn group (P burn site allays the neutrophil response to thermal injury and reduces tissue necrosis. This decrease in inflammation and tissue necrosis is at least partially because of TNF-α and IFN-β signaling. Apyrase could be used as topical inflammatory regulators to quell the injury caused by inflammation.

  16. Estimation of the common cause failure probabilities on the component group with mixed testing scheme

    International Nuclear Information System (INIS)

    Hwang, Meejeong; Kang, Dae Il

    2011-01-01

    Highlights: ► This paper presents a method to estimate the common cause failure probabilities on the common cause component group with mixed testing schemes. ► The CCF probabilities are dependent on the testing schemes such as staggered testing or non-staggered testing. ► There are many CCCGs with specific mixed testing schemes in real plant operation. ► Therefore, a general formula which is applicable to both alternate periodic testing scheme and train level mixed testing scheme was derived. - Abstract: This paper presents a method to estimate the common cause failure (CCF) probabilities on the common cause component group (CCCG) with mixed testing schemes such as the train level mixed testing scheme or the alternate periodic testing scheme. In the train level mixed testing scheme, the components are tested in a non-staggered way within the same train, but the components are tested in a staggered way between the trains. The alternate periodic testing scheme indicates that all components in the same CCCG are tested in a non-staggered way during the planned maintenance period, but they are tested in a staggered way during normal plant operation. Since the CCF probabilities are dependent on the testing schemes such as staggered testing or non-staggered testing, CCF estimators have two kinds of formulas in accordance with the testing schemes. Thus, there are general formulas to estimate the CCF probability on the staggered testing scheme and non-staggered testing scheme. However, in real plant operation, there are many CCCGs with specific mixed testing schemes. Recently, Barros () and Kang () proposed a CCF factor estimation method to reflect the alternate periodic testing scheme and the train level mixed testing scheme. In this paper, a general formula which is applicable to both the alternate periodic testing scheme and the train level mixed testing scheme was derived.

  17. Mastectomy skin necrosis after microsurgical breast reconstruction.

    Science.gov (United States)

    Vargas, Christina R; Koolen, Pieter G; Anderson, Katarina E; Paul, Marek A; Tobias, Adam M; Lin, Samuel J; Lee, Bernard T

    2015-10-01

    Mastectomy skin necrosis represents a significant clinical morbidity after immediate breast reconstruction. In addition to aesthetic deformity, necrosis of the native mastectomy skin may require debridement, additional reconstruction, or prolonged wound care and potentially delay oncologic treatment. This study aims to evaluate patient and procedural characteristics to identify predictors of mastectomy skin necrosis after microsurgical breast reconstruction. A retrospective review was performed of all immediate microsurgical breast reconstructions performed at a single academic center. Patient records were queried for age, diabetes, active smoking, previous breast surgery, preoperative radiation, preoperative chemotherapy, body mass index, mastectomy type, mastectomy weight, flap type, autologous flap type, and postoperative mastectomy skin flap necrosis. There were 746 immediate autologous microsurgical flaps performed by three plastic surgeons at our institution during the study period. The incidence of mastectomy skin flap necrosis was 13.4%. Univariate analysis revealed a significantly higher incidence of mastectomy skin necrosis in patients with higher mastectomy weight (P mastectomy type. Multivariate analysis demonstrated statistically significant associations between mastectomy skin necrosis and both increasing mastectomy weight (odds ratio 1.348 per quartile increase, P = 0.009) and diabetes (odds ratio 2.356, P = 0.011). Increasing mastectomy weight and coexisting diabetes are significantly associated with postoperative mastectomy skin necrosis after microsurgical reconstruction. These characteristics should be considered during patient counseling, procedure selection, operative planning, and intraoperative tissue viability assessment. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Heart Failure in Women

    Science.gov (United States)

    Bozkurt, Biykem; Khalaf, Shaden

    2017-01-01

    Heart failure is an important cause of morbidity and mortality in women, and they tend to develop it at an older age compared to men. Heart failure with preserved ejection fraction is more common in women than in men and accounts for at least half the cases of heart failure in women. When comparing men and women who have heart failure and a low left ventricular ejection fraction, the women are more symptomatic and have a similarly poor outcome. Overall recommendations for guideline-directed medical therapies show no differences in treatment approaches between men and women. Overall, women are generally underrepresented in clinical trials for heart failure. Further studies are needed to shed light into different mechanisms, causes, and targeted therapies of heart failure in women. PMID:29744014

  19. Accelerated avascular necrosis after single intra-articular injection of corticosteroid into the hip joint

    OpenAIRE

    Kassam, A M

    2010-01-01

    Avascular necrosis (AVN) involves destruction of the hip joint. Long-term use of steroids has been shown to cause AVN. This article presents a case of intra-articular injection of steroid causing a rapid onset of AVN in the hip joint. Bone histology at time of total hip replacement showed evidence of AVN and no evidence of infection.

  20. Sensitivity analysis on the effect of software-induced common cause failure probability in the computer-based reactor trip system unavailability

    International Nuclear Information System (INIS)

    Kamyab, Shahabeddin; Nematollahi, Mohammadreza; Shafiee, Golnoush

    2013-01-01

    Highlights: ► Importance and sensitivity analysis has been performed for a digitized reactor trip system. ► The results show acceptable trip unavailability, for software failure probabilities below 1E −4 . ► However, the value of Fussell–Vesley indicates that software common cause failure is still risk significant. ► Diversity and effective test is founded beneficial to reduce software contribution. - Abstract: The reactor trip system has been digitized in advanced nuclear power plants, since the programmable nature of computer based systems has a number of advantages over non-programmable systems. However, software is still vulnerable to common cause failure (CCF). Residual software faults represent a CCF concern, which threat the implemented achievements. This study attempts to assess the effectiveness of so-called defensive strategies against software CCF with respect to reliability. Sensitivity analysis has been performed by re-quantifying the models upon changing the software failure probability. Importance measures then have been estimated in order to reveal the specific contribution of software CCF in the trip failure probability. The results reveal the importance and effectiveness of signal and software diversity as applicable strategies to ameliorate inefficiencies due to software CCF in the reactor trip system (RTS). No significant change has been observed in the rate of RTS failure probability for the basic software CCF greater than 1 × 10 −4 . However, the related Fussell–Vesley has been greater than 0.005, for the lower values. The study concludes that consideration of risk associated with the software based systems is a multi-variant function which requires compromising among them in more precise and comprehensive studies

  1. Etiology and outcome of acute renal failure in pregnancy.

    Science.gov (United States)

    Hassan, Irfana; Junejo, Abdul Manan; Dawani, Manohar Lal

    2009-11-01

    To determine the etiology and outcome of Acute Renal Failure (ARF) in pregnancy. A case series. Nephrology Department of the Jinnah Postgraduate Medical Centre, Karachi, from August 2007 to July 2008. Pregnant women who were healthy previously and had developed ARF, diagnosed on oliguria (urine output 2 mg%) were included in the study. Percutaneous renal biopsy was performed for delayed recovery, i.e. after three weeks. Patients were followed up for a period of 6 months. Percentages were calculated for qualitative variables i.e. causes of ARF, mortality, morbidity and outcome in form of complete recovery, partial recovery, demise and non-recovery. A total of 43 patients with pregnancy-related ARF were included in the study. The puerperal group comprised 36 patients (83.7%). Haemorrhage was the etiology for ARF in 25 (58.1%), antepartum haemorrhage APH in 8 (18.6%) and postpartum haemorrhage PPH in 16 (37.2%) of patients. In 12 (27.9%), puerperal sepsis was the etiological factor, while 4 (9.3%) patients had DIC on presentation. Pre-eclampsia, eclampsia and HELLP syndrome accounted for 5 (11.6%). While 1 (2.3%) was diagnosed with hemolytic uremic syndrome and another one was diagnosed as ARF secondary to hypotension produced by hyperemesis gravidarum. Renal biopsy was performed in 31 patients showing that 10 had acute cortical necrosis and 21 had acute tubular necrosis. Maternal mortality was 16.2% (n=7). Of the 36 (83.7%) surviving patients, 18 (41.4%) had complete recovery of renal function; 12 (27.9%) had partial recovery; and 6 (13.9%) required chronic dialysis. Pregnancy-related ARF was associated with poor outcome. Antepartum and postpartum haemorrhage were the most common cause of ARF in pregnancy.

  2. Analysis of the prevalence and causes of ultrafiltration failure during long-term peritoneal dialysis: a cross-sectional study

    NARCIS (Netherlands)

    Smit, Watske; Schouten, Natalie; van den Berg, Nicole; Langedijk, Monique J.; Struijk, Dirk G.; Krediet, Raymond T.

    2004-01-01

    BACKGROUND: Ultrafiltration failure (UFF) is a major complication of peritoneal dialysis (PD). It can occur at any stage of PD, but develops in time and is, therefore, especially important in long-term treatment. To investigate its prevalence and to identify possible causes, we performed a

  3. Procedures for conducting common cause failure analysis in probabilistic safety assessment

    International Nuclear Information System (INIS)

    1992-05-01

    The principal objective of this report is to supplement the procedure developed in Mosleh et al. (1988, 1989) by providing more explicit guidance for a practical approach to common cause failures (CCF) analysis. The detailed CCF analysis following that procedure would be very labour intensive and time consuming. This document identifies a number of options for performing the more labour intensive parts of the analysis in an attempt to achieve a balance between the need for detail, the purpose of the analysis and the resources available. The document is intended to be compatible with the Agency's Procedures for Conducting Probabilistic Safety Assessments for Nuclear Power Plants (IAEA, 1992), but can be regarded as a stand-alone report to be used in conjunction with NUREG/CR-4780 (Mosleh et al., 1988, 1989) to provide additional detail, and discussion of key technical issues

  4. Recent insights from the international common-cause failure data exchange project

    Energy Technology Data Exchange (ETDEWEB)

    Kreuser, Albert [Gesellschaft fur Anlagen- und Reaktorsicherheit (GRS) gGmbH, Cologne (Germany); Johanson, Gunner [AF Industry, Stockholm (Sweden)

    2017-03-15

    Common-cause failure (CCF) events can significantly impact the availability of safety systems of nuclear power plants. For this reason, the International Common Cause Data Exchange (ICDE) project was initiated by several countries in 1994. Since 1997 it has been operated within the Organisation for Economic Co-operation and Development (OECD)/Nuclear Energy Agency (NEA) framework and has successfully been operated over six consecutive terms (the current term being 2015–2017). The ICDE project allows multiple countries to collaborate and exchange CCF data to enhance the quality of risk analyses, which include CCF modeling. As CCF events are typically rare, most countries do not experience enough CCF events to perform meaningful analyses. Data combined from several countries, however, have yielded sufficient data for more rigorous analyses. The ICDE project has meanwhile published 11 reports on the collection and analysis of CCF events of specific component types (centrifugal pumps, emergency diesel generators, motor operated valves, safety and relief valves, check valves, circuit breakers, level measurement, control rod drive assemblies, and heat exchangers) and two topical reports. This paper presents recent activities and lessons learnt from the data collection and the results of topical analysis on emergency diesel generator CCF impacting entire exposed population.

  5. Recent Insights from the International Common-Cause Failure Data Exchange Project

    Directory of Open Access Journals (Sweden)

    Albert Kreuser

    2017-03-01

    Full Text Available Common-cause failure (CCF events can significantly impact the availability of safety systems of nuclear power plants. For this reason, the International Common Cause Data Exchange (ICDE project was initiated by several countries in 1994. Since 1997 it has been operated within the Organisation for Economic Co-operation and Development (OECD/Nuclear Energy Agency (NEA framework and has successfully been operated over six consecutive terms (the current term being 2015–2017. The ICDE project allows multiple countries to collaborate and exchange CCF data to enhance the quality of risk analyses, which include CCF modeling. As CCF events are typically rare, most countries do not experience enough CCF events to perform meaningful analyses. Data combined from several countries, however, have yielded sufficient data for more rigorous analyses. The ICDE project has meanwhile published 11 reports on the collection and analysis of CCF events of specific component types (centrifugal pumps, emergency diesel generators, motor operated valves, safety and relief valves, check valves, circuit breakers, level measurement, control rod drive assemblies, and heat exchangers and two topical reports. This paper presents recent activities and lessons learnt from the data collection and the results of topical analysis on emergency diesel generator CCF impacting entire exposed population.

  6. Managing Feelings about Heart Failure

    Science.gov (United States)

    ... About Heart Failure Module 6: Managing Feelings About Heart Failure Download Module Order Hardcopy Heart failure can cause ... professional help for emotional problems. Common Feelings About Heart Failure It is common for people to feel depressed ...

  7. Assessment of the causes of failures of roto-dynamic equipment in Cirus

    International Nuclear Information System (INIS)

    Rao, K.N.; Singh, S.; Ganeshan, P.

    1994-01-01

    As a part of Cirus reactor life extension program study, a service life evaluation of critical roto-dynamic equipment in Cirus such as primary coolant pumps, and their concrete foundation structures, pressurised water loop pumps, main air compressors and supply and exhaust fans, was performed. An assessment of the causes of failures of roto-dynamic equipment in Cirus was done. Based on assessment of the degradation mitigating features and comparison to similar roto-dynamic equipment and their concrete foundation structures, it was concluded that life extension of these roto-dynamic equipment and their structures is feasible. To support this conclusion a program involving: a) non-destructive testing, b) surveillance and monitoring and, c) preventive maintenance is recommended. (author). 4 refs

  8. An informatics-based approach to reducing heart failure all-cause readmissions: the Stanford heart failure dashboard.

    Science.gov (United States)

    Banerjee, Dipanjan; Thompson, Christine; Kell, Charlene; Shetty, Rajesh; Vetteth, Yohan; Grossman, Helene; DiBiase, Aria; Fowler, Michael

    2017-05-01

    Reduction of 30-day all-cause readmissions for heart failure (HF) has become an important quality-of-care metric for health care systems. Many hospitals have implemented quality improvement programs designed to reduce 30-day all-cause readmissions for HF. Electronic medical record (EMR)-based measures have been employed to aid in these efforts, but their use has been largely adjunctive to, rather than integrated with, the overall effort. We hypothesized that a comprehensive EMR-based approach utilizing an HF dashboard in addition to an established HF readmission reduction program would further reduce 30-day all-cause index hospital readmission rates for HF. After establishing a quality improvement program to reduce 30-day HF readmission rates, we instituted EMR-based measures designed to improve cohort identification, intervention tracking, and readmission analysis, the latter 2 supported by an electronic HF dashboard. Our primary outcome measure was the 30-day index hospital readmission rate for HF, with secondary measures including the accuracy of identification of patients with HF and the percentage of patients receiving interventions designed to reduce all-cause readmissions for HF. The HF dashboard facilitated improved penetration of our interventions and reduced readmission rates by allowing the clinical team to easily identify cohorts with high readmission rates and/or low intervention rates. We significantly reduced 30-day index hospital all-cause HF readmission rates from 18.2% at baseline to 14% after implementation of our quality improvement program ( P  = .045). Implementation of our EMR-based approach further significantly reduced 30-day index hospital readmission rates for HF to 10.1% ( P for trend = .0001). Daily time to screen patients decreased from 1 hour to 15 minutes, accuracy of cohort identification improved from 83% to 94.6% ( P  = .0001), and the percentage of patients receiving our interventions, such as patient education

  9. Heart Failure

    OpenAIRE

    McMurray, John; Ponikowski, Piotr

    2011-01-01

    Heart failure occurs in 3% to 4% of adults aged over 65 years, usually as a consequence of coronary artery disease or hypertension, and causes breathlessness, effort intolerance, fluid retention, and increased mortality. The 5-year mortality in people with systolic heart failure ranges from 25% to 75%, often owing to sudden death following ventricular arrhythmia. Risks of cardiovascular events are increased in people with left ventricular systolic dysfunction (LVSD) or heart failure.

  10. Regulation of Tumor Progression by Programmed Necrosis

    Directory of Open Access Journals (Sweden)

    Su Yeon Lee

    2018-01-01

    Full Text Available Rapidly growing malignant tumors frequently encounter hypoxia and nutrient (e.g., glucose deprivation, which occurs because of insufficient blood supply. This results in necrotic cell death in the core region of solid tumors. Necrotic cells release their cellular cytoplasmic contents into the extracellular space, such as high mobility group box 1 (HMGB1, which is a nonhistone nuclear protein, but acts as a proinflammatory and tumor-promoting cytokine when released by necrotic cells. These released molecules recruit immune and inflammatory cells, which exert tumor-promoting activity by inducing angiogenesis, proliferation, and invasion. Development of a necrotic core in cancer patients is also associated with poor prognosis. Conventionally, necrosis has been thought of as an unregulated process, unlike programmed cell death processes like apoptosis and autophagy. Recently, necrosis has been recognized as a programmed cell death, encompassing processes such as oncosis, necroptosis, and others. Metabolic stress-induced necrosis and its regulatory mechanisms have been poorly investigated until recently. Snail and Dlx-2, EMT-inducing transcription factors, are responsible for metabolic stress-induced necrosis in tumors. Snail and Dlx-2 contribute to tumor progression by promoting necrosis and inducing EMT and oncogenic metabolism. Oncogenic metabolism has been shown to play a role(s in initiating necrosis. Here, we discuss the molecular mechanisms underlying metabolic stress-induced programmed necrosis that promote tumor progression and aggressiveness.

  11. A standardized model for predicting flap failure using indocyanine green dye

    Science.gov (United States)

    Zimmermann, Terence M.; Moore, Lindsay S.; Warram, Jason M.; Greene, Benjamin J.; Nakhmani, Arie; Korb, Melissa L.; Rosenthal, Eben L.

    2016-03-01

    Techniques that provide a non-invasive method for evaluation of intraoperative skin flap perfusion are currently available but underutilized. We hypothesize that intraoperative vascular imaging can be used to reliably assess skin flap perfusion and elucidate areas of future necrosis by means of a standardized critical perfusion threshold. Five animal groups (negative controls, n=4; positive controls, n=5; chemotherapy group, n=5; radiation group, n=5; chemoradiation group, n=5) underwent pre-flap treatments two weeks prior to undergoing random pattern dorsal fasciocutaneous flaps with a length to width ratio of 2:1 (3 x 1.5 cm). Flap perfusion was assessed via laser-assisted indocyanine green dye angiography and compared to standard clinical assessment for predictive accuracy of flap necrosis. For estimating flap-failure, clinical prediction achieved a sensitivity of 79.3% and a specificity of 90.5%. When average flap perfusion was more than three standard deviations below the average flap perfusion for the negative control group at the time of the flap procedure (144.3+/-17.05 absolute perfusion units), laser-assisted indocyanine green dye angiography achieved a sensitivity of 81.1% and a specificity of 97.3%. When absolute perfusion units were seven standard deviations below the average flap perfusion for the negative control group, specificity of necrosis prediction was 100%. Quantitative absolute perfusion units can improve specificity for intraoperative prediction of viable tissue. Using this strategy, a positive predictive threshold of flap failure can be standardized for clinical use.

  12. Quantitative analysis of Common cause failures in systems with a high level of redundancies

    International Nuclear Information System (INIS)

    Pereira Pagan, B.; Lopez Fdez-Quevedo, C.; Gomez, F.; Cuallado, G.

    1996-01-01

    The importance of common cause failures in plants with systems featuring a high level of redundancies, and the difficulty implied by the lack of data on specific KWU design plants have been taken into account right from the beginning of the PSA. for this reason it has been necessary to analyse the different methodologies by establishing a procedure based on the documentation available, studying its applicability and solving problems arising from of the lack of information needed to make reliable statistical estimates. It was finally decided to systematically use the alpha parameter method. In case where this was not possible, the modified Beta factor method was used, and if there were no data available for the type of component considered, generic alpha values were used. this process required the definition of certain criteria to maintain coherent parameter estimates. The final result shows the impact of the number of redundancies considered in the estimated failure probability or rare. This process is valid for any size of system modelled. (Author)

  13. Celiac artery trunk thrombosis presenting as acute liver failure

    International Nuclear Information System (INIS)

    Akbarian, M.A.; Kahrom, M.; Kahrom, H.

    2011-01-01

    Acute mesenteric ischemia is a life-threatening vascular emergency that requires early diagnosis and intervention to adequately restore mesenteric blood flow and to prevent bowel necrosis and patient death. While, almost always superior and inferior mesenteric arteries are involved, we report a 57-year-old male with an unusual celiac artery trunk thrombosis leading to gastero-duodenal and hepato-splenic infarction, and presenting an acute liver failure. (author)

  14. Nonacetaminophen Drug-Induced Acute Liver Failure.

    Science.gov (United States)

    Thomas, Arul M; Lewis, James H

    2018-05-01

    Acute liver failure of all causes is diagnosed in between 2000 and 2500 patients annually in the United States. Drug-induced acute liver failure is the leading cause of acute liver failure, accounting for more than 50% of cases. Nonacetaminophen drug injury represents 11% of all cases in the latest registry from the US Acute Liver Failure Study Group. Although rare, acute liver failure is clinically dramatic when it occurs, and requires a multidisciplinary approach to management. In contrast with acetaminophen-induced acute liver failure, non-acetaminophen-induced acute liver failure has a more ominous prognosis with a lower liver transplant-free survival. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. The Causes of Failure of the European Constitution From the Perspective of the Constitution-Making Process

    Directory of Open Access Journals (Sweden)

    Robert Podolnjak

    2006-01-01

    Full Text Available The basic argument of the article is that the main causes of failure of the European Constitution stem from an inadequate preparation and implementation of a complex procedure of constitution-making for a federation of countries on a continental scale. This process includes the issues of temporal aspects of constitutionmaking, the subject of constitution-making, the text of the constitution, the strategy of constitutional ratifi cation and the constitution-makers themselves. The principal causes of failure of the European Constitution will be presented in the form of certain preliminary assumptions, which will then be examined in the light of certain comparative experiences of constitution-making in two federal systems – the American and the Swiss system. The primary mistakes of the European constitution-making are refl ected in the lack of an appropriate moment for making the constitution, in the vagueness of the document in terms of its constitutional or contractual quality, in the creation of a text of the Constitution which is completely incomprehensible to the average citizen, in the making of the Constitution without a vision or ambition, in the complete lack of any strategy of ratifi cation of the Constitution, in the insistence on the direct participation of the people in the adoption of the Constitution, which is legally and politically considered primarily an international treaty, and in badly managed media presentation and defence of the Constitution before the European public. The most important mistakes, crucial to the failure of the Constitution, are the ambivalent approach of the European constitutionmakers to the mode of ratifi cation of the Constitution, and their disregard of the constitution-making experience of other federal countries.

  16. What caused Chicago bank failures in the Great Depression? A look at the 1920s.

    OpenAIRE

    Natacha Postel-Vinay

    2015-01-01

    This paper reassesses the causes of Chicago bank failures during the Great Depression by tracking the evolution of their balance sheets in the 1920s. I find that all Chicago banks suffered tremendous deposit withdrawals; however banks that failed earlier in the 1930s had invested more in mortgages in the 1920s. The main problem with mortgages was their lack of liquidity, not their quality. Banks heavily engaged in mortgages did not have enough liquid assets to face the withdrawals and failed....

  17. [Necrosis in fingers and toes following local anaesthesia with adrenaline--an urban legend?].

    Science.gov (United States)

    Finsen, Vilhjalmur

    2013-09-17

    It is often maintained that a local anaesthetic (usually lidocaine) with adrenaline must not be used in fingers and toes because it may cause necrosis due to vascular spasm in end arteries. This review article is an attempt to find evidence to support this warning. Relevant literature was found by means of searches in PubMed limited downwards to 1946 and in EMBASE from 1980 to 2012, and in reference lists. Five review articles on finger necrosis following local anaesthesia concluded that lidocaine with adrenaline does not entail a risk of ischaemic injury. One article found 48 reported cases of finger necrosis in the period 1880 to 2000. Most were from the first half of the 1900s, and none involved lidocaine. Gangrene of part of the finger tip has subsequently been described in one patient with Raynaud's syndrome. No cases of necrosis have been described in a large number of reported accidents in which EpiPen injections contained the same quantity of adrenaline as is found in 60 ml lidocaine with adrenaline. Over a quarter of a million reports have been made of operations on feet, hands, fingers and toes anaesthetised with lidocaine with adrenaline without resulting necrosis. There are no grounds for the warning against using lidocaine with adrenaline in fingers and toes. This anaesthetic offers considerable practical advantages. Care should be taken with infected fingers or fingers with poor circulation.

  18. Fatal Fulminant Hepatic Failure from Adenovirus in Allogeneic Bone Marrow Transplant Patients

    Directory of Open Access Journals (Sweden)

    Jatin M. Vyas

    2012-01-01

    Full Text Available We report two cases of fatal hepatic failure in patients who received matched unrelated bone marrow transplantation. Both patients presented with high fevers, abnormal liver functions tests, and hypodense lesions in the liver by CT scan. Histologic examination of postmortem liver samples demonstrated extensive necrosis, and immunohistochemistry was positive for adenovirus.

  19. Acute respiratory failure caused by organizing pneumonia secondary to antineoplastic therapy for non-Hodgkin's lymphoma

    Science.gov (United States)

    Santana, Adriell Ramalho; Amorim, Fábio Ferreira; Soares, Paulo Henrique Alves; de Moura, Edmilson Bastos; Maia, Marcelo de Oliveira

    2012-01-01

    Interstitial lung diseases belong to a group of diseases that typically exhibit a subacute or chronic progression but that may cause acute respiratory failure. The male patient, who was 37 years of age and undergoing therapy for non-Hodgkin's lymphoma, was admitted with cough, fever, dyspnea and acute hypoxemic respiratory failure. Mechanical ventilation and antibiotic therapy were initiated but were associated with unfavorable progression. Thoracic computed tomography showed bilateral pulmonary "ground glass" opacities. Methylprednisolone pulse therapy was initiated with satisfactory response because the patient had used three drugs related to organizing pneumonia (cyclophosphamide, doxorubicin and rituximab), and the clinical and radiological symptoms were suggestive. Organizing pneumonia may be idiopathic or linked to collagen diseases, drugs and cancer and usually responds to corticosteroid therapy. The diagnosis was anatomopathological, but the patient's clinical condition precluded performing a lung biopsy. Organizing pneumonia should be a differential diagnosis in patients with apparent pneumonia and a progression that is unfavorable to antimicrobial treatment. PMID:23917942

  20. Methylene Blue Dye-Induced Skin Necrosis in Immediate Breast Reconstruction: Evaluation and Management

    Directory of Open Access Journals (Sweden)

    Ji Hwan Lee

    2014-05-01

    Full Text Available Background For early breast cancer patients, skin-sparing mastectomy or nipple-sparing mastectomy with sentinel lymph node biopsy has become the mainstream treatment for immediate breast reconstruction in possible cases. However, a few cases of skin necrosis caused by methylene blue dye (MBD used for sentinel lymph node localization have been reported. Methods Immediate breast reconstruction using a silicone implant was performed on 35 breasts of 34 patients after mastectomy. For sentinel lymph node localization, 1% MBD (3 mL was injected into the subareolar area. The operation site was inspected in the postoperative evaluation. Results Six cases of immediate breast reconstruction using implants were complicated by methylene blue dye. One case of local infection was improved by conservative treatment. In two cases, partial necrosis and wound dehiscence of the incision areas were observed; thus, debridement and closure were performed. Of the three cases of wide skin necrosis, two cases underwent removal of the dead tissue and implants, followed by primary closure. In the other case, the breast implant was salvaged using latissimus dorsi musculocutaneous flap reconstruction. Conclusions The complications were caused by MBD toxicity, which aggravated blood disturbance and skin tension after implant insertion. When planning immediate breast reconstruction using silicone implants, complications of MBD should be discussed in detail prior to surgery, and appropriate management in the event of complications is required.

  1. Clinical characteristics and causes of heart failure adherence to treatment guidelines and mortality of patients with acute heart failure: Experience at Groote Schuur Hospital Cape Town South Africa

    Directory of Open Access Journals (Sweden)

    P Szymanski

    2018-02-01

    Full Text Available Background. There is limited information on acute heart failure (AHF and its treatment in sub-Saharan Africa.Objective. To describe the clinical characteristics and causes of heart failure (HF, adherence to HF treatment guidelines, and mortality of patients with AHF presenting to Groote Schuur Hospital (GSH, Cape Town, South Africa.Methods. This sub-study of The Sub-Saharan Africa Survey of Heart Failure (THESUS-HF was a prospective and observational survey that focused on the enrolment and follow-up of additional patients with AHF presenting to GSH and entered into the existing registry after publication of the primary THESUS-HF article in 2012. The patients were classified into prevalent (existing or incident (new cases of HF.Results. Of the 119 patients included, 69 (58.0% were female and the mean (standard deviation age was 49.9 (16.3 years. The majority of prevalent cases were patients of mixed ancestry (63.3%, and prevalent cases had more hypertension (70.0%, diabetes mellitus (36.7%, hyperlipidaemia (33.3% and ischaemic heart disease (IHD (36.7% than incident cases. The top five causes of HF were cardiomyopathy (20.2%, IHD (19.3%, rheumatic valvular heart disease (RHD (18.5%, cor pulmonale (11.8% and hypertension (10.1%, with the remaining 20.1% consisting of miscellaneous causes including pericarditis, toxins and congenital heart disease. Most patients received renin-angiotensin system blockers and loop diuretics on discharge. There was a low rate of beta-blocker, aldosterone antagonist and digoxin use. Rehospitalisation within 180 days occurred in 25.2% of cases. In-hospital mortality was 8.4% and the case fatality rate at 6 months was 26.1%.Conclusion. In Cape Town, the main causes of AHF are cardiomyopathy, IHD and RHD. AHF affects a young population and is associated with a high rate of rehospitalisation and mortality. There is serious under-use of beta-blockers, aldosterone antagonists and digoxin. Emphasis on the rigorous

  2. [Establishment of a D-galactosamine/lipopolysaccharide induced acute-on-chronic liver failure model in rats].

    Science.gov (United States)

    Liu, Xu-hua; Chen, Yu; Wang, Tai-ling; Lu, Jun; Zhang, Li-jie; Song, Chen-zhao; Zhang, Jing; Duan, Zhong-ping

    2007-10-01

    To establish a practical and reproducible animal model of human acute-on-chronic liver failure for further study of the pathophysiological mechanism of acute-on-chronic liver failure and for drug screening and evaluation in its treatment. Immunological hepatic fibrosis was induced by human serum albumin in Wistar rats. In rats with early-stage cirrhosis (fibrosis stage IV), D-galactosamine and lipopolysaccharide were administered. Mortality and survival time were recorded in 20 rats. Ten rats were sacrificed at 4, 8, and 12 hours. Liver function tests and plasma cytokine levels were measured after D-galactosamine/lipopolysaccharide administration and liver pathology was studied. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Most of the rats treated with human albumin developed cirrhosis and fibrosis, and 90% of them died from acute liver failure after administration of D-galactosamine/lipopolysaccharide, with a mean survival time of (16.1+/-3.7) hours. Liver histopathology showed massive or submassive necrosis of the regenerated nodules, while fibrosis septa were intact. Liver function tests were compatible with massive necrosis of hepatocytes. Plasma level of TNFalpha increased significantly, parallel with the degree of the hepatocytes apoptosis. Plasma IL-10 levels increased similarly as seen in patients with acute-on-chronic liver failure. We established an animal model of acute-on-chronic liver failure by treating rats with human serum albumin and later with D-galactosamine and lipopolysaccharide. TNFalpha-mediated liver cell apoptoses plays a very important role in the pathogenesis of acute liver failure.

  3. THE PATHOLOGY OF BONE MARROW FAILURE

    OpenAIRE

    Leguit , Roos; Van Den Tweel , Jan G

    2010-01-01

    Abstract An important indication for bone marrow investigation is the presence of bone marrow failure, which manifests itself as (pan)cytopenia. The causes of cytopenia are varied and differ considerable between childhood and adulthood. In the paediatric age group, inherited bone marrow failure syndromes are important causes of bone marrow failure but they play only a minor role in later life. This review gives a comprehensive overview of bone marrow failure disorders in children a...

  4. Walled-off pancreatic necrosis and other current concepts in the radiological assessment of acute pancreatitis

    International Nuclear Information System (INIS)

    Cunha, Elen Freitas de Cerqueira; Rocha, Manoel de Souza; Pereira, Fabio Payao; Blasbalg, Roberto; Baroni, Ronaldo Hueb

    2014-01-01

    Acute pancreatitis is an inflammatory condition caused by intracellular activation and extravasation of inappropriate proteolytic enzymes determining destruction of pancreatic parenchyma and peripancreatic tissues. This is a fairly common clinical condition with two main presentations, namely, endematous pancreatitis - a less severe presentation - and necrotizing pancreatitis - the most severe presentation that affects a significant part of patients. The radiological evaluation, particularly by computed tomography, plays a fundamental role in the definition of the management of severe cases, especially regarding the characterization of local complications with implications in the prognosis and in the definition of the therapeutic approach. New concepts include the subdivision of necrotizing pancreatitis into the following presentations: pancreatic parenchymal necrosis with concomitant peripancreatic tissue necrosis, and necrosis restricted to peripancreatic tissues. Moreover, there was a systematization of the terms acute peripancreatic fluid collection, pseudocyst, post-necrotic pancreatic/peripancreatic fluid collections and walled-off pancreatic necrosis. The knowledge about such terms is extremely relevant to standardize the terminology utilized by specialists involved in the diagnosis and treatment of these patients. (author)

  5. Walled-off pancreatic necrosis and other current concepts in the radiological assessment of acute pancreatitis

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Elen Freitas de Cerqueira [Image Memorial/DASA and Diagnoson Medicina Diagnostica, Salvador, BA (Brazil); Rocha, Manoel de Souza; Pereira, Fabio Payao; Blasbalg, Roberto; Baroni, Ronaldo Hueb [Universidade de Sao Paulo (FM/USPU), Sao Paulo, SP (Brazil). Faculdade de Medicina

    2014-05-15

    Acute pancreatitis is an inflammatory condition caused by intracellular activation and extravasation of inappropriate proteolytic enzymes determining destruction of pancreatic parenchyma and peripancreatic tissues. This is a fairly common clinical condition with two main presentations, namely, endematous pancreatitis - a less severe presentation - and necrotizing pancreatitis - the most severe presentation that affects a significant part of patients. The radiological evaluation, particularly by computed tomography, plays a fundamental role in the definition of the management of severe cases, especially regarding the characterization of local complications with implications in the prognosis and in the definition of the therapeutic approach. New concepts include the subdivision of necrotizing pancreatitis into the following presentations: pancreatic parenchymal necrosis with concomitant peripancreatic tissue necrosis, and necrosis restricted to peripancreatic tissues. Moreover, there was a systematization of the terms acute peripancreatic fluid collection, pseudocyst, post-necrotic pancreatic/peripancreatic fluid collections and walled-off pancreatic necrosis. The knowledge about such terms is extremely relevant to standardize the terminology utilized by specialists involved in the diagnosis and treatment of these patients. (author)

  6. Spectrum of pathological lesions in acute renal failure

    International Nuclear Information System (INIS)

    Kazi, J.I.; Mubarak, M.; Akhter, F.; Ahmed, E.; Naqvi, R.; Naqvi, S.A.; Rizvi, S.A.H.

    2003-01-01

    Objective: To determine the spectrum of pathological lesions in percutaneous renal biopsies of patients with acute renal failure (ARF) and to compare our findings with reported literature. Results: A total of 158 patients were studied. Of these 57 were males and 101 females. Mean age of the patients in this series were 30.7 years with a range of 6 to 75 years. Of these 61 (38.6%) had acute tubular necrosis, 36 (22.7%) acute cortical necrosis and 49(31%) patients had various types of glomerculonephriits (GN). Eight patients (5%) had acute tubulointerstitial nephritis, 3(1.8%) acute pyelonephritis and one patient had mucormycosis. Conclusion: This study showed that even in the selected population of biopsied ARF cases, there was a high prevalence of ischemic renal disease. A substantial number of cases in unexplained ARF on renal biopsy were due to various forms of glomerulonephritis. (author)

  7. Acrolein Can Cause Cardiovascular Disease: A Review.

    Science.gov (United States)

    Henning, Robert J; Johnson, Giffe T; Coyle, Jayme P; Harbison, Raymond D

    2017-07-01

    Acrolein is a highly reactive unsaturated aldehyde that is formed during the burning of gasoline and diesel fuels, cigarettes, woods and plastics. In addition, acrolein is generated during the cooking or frying of food with fats or oils. Acrolein is also used in the synthesis of many organic chemicals and as a biocide in agricultural and industrial water supply systems. The total emissions of acrolein in the United States from all sources are estimated to be 62,660 tons/year. Acrolein is classified by the Environmental Protection Agency as a high-priority air and water toxicant. Acrolein can exert toxic effects following inhalation, ingestion, and dermal exposures that are dose dependent. Cardiovascular tissues are particularly sensitive to the toxic effects of acrolein based primarily on in vitro and in vivo studies. Acrolein can generate free oxygen radical stress in the heart, decrease endothelial nitric oxide synthase phosphorylation and nitric oxide formation, form cytoplasmic and nuclear protein adducts with myocyte and vascular endothelial cell proteins and cause vasospasm. In this manner, chronic exposure to acrolein can cause myocyte dysfunction, myocyte necrosis and apoptosis and ultimately lead to cardiomyopathy and cardiac failure. Epidemiological studies of acrolein exposure and toxicity should be developed and treatment strategies devised that prevent or significantly limit acrolein cardiovascular toxicity.

  8. Virological failure and all-cause mortality in HIV-positive adults with low-level viremia during antiretroviral treatment.

    Directory of Open Access Journals (Sweden)

    Olof Elvstam

    Full Text Available Although most HIV-infected individuals achieve undetectable viremia during antiretroviral therapy (ART, a subset have low-level viremia (LLV of varying duration and magnitude. The impact of LLV on treatment outcomes is unclear. We investigated the association between LLV and virological failure and/or all-cause mortality among Swedish patients receiving ART.HIV-infected patients from two Swedish HIV centers were identified from the nationwide register InfCare HIV. Subjects aged ≥15 years with triple agent ART were included at 12 months after treatment initiation if ≥2 following viral load measurements were available. Patients with 2 consecutive HIV RNA values ≥1000 copies/mL at this time point were excluded. Participants were stratified into four categories depending on viremia profiles: permanently suppressed viremia (<50 copies/mL, LLV 50-199 copies/mL, LLV 200-999 copies/mL and viremia ≥1000 copies/mL. Association between all four viremia categories and all-cause death was calculated using survival analysis with viremia as a time-varying covariate, so that patients could change viremia category during follow-up. Association between the three lower categories and virological failure (≥2 consecutive measurements ≥1000 copies/mL was calculated in a similar manner.LLV 50-199 copies/mL was recorded in 70/1015 patients (6.9% and LLV 200-999 copies/mL in 89 (8.8% during 7812 person-years of follow-up (median 6.5 years. LLV 200-999 copies/mL was associated with virological failure (adjusted hazard ratio 3.14 [95% confidence interval 1.41-7.03, p<0.01], whereas LLV 50-199 copies/mL was not (1.01 [0.34-4.31, p = 0.99]; median follow-up 4.5 years. LLV 200-999 copies/mL had an adjusted mortality hazard ratio of 2.29 (0.98-5.32, p = 0.05 and LLV 50-199 copies/mL of 2.19 (0.90-5.37, p = 0.09.In this Swedish cohort followed during ART for a median of 4.5 years, LLV 200-999 copies/mL was independently associated with virological failure. Patients

  9. Comparing Two Different Approaches to the Modeling of the Common Cause Failures in Fault Trees

    International Nuclear Information System (INIS)

    Vukovic, I.; Mikulicic, V.; Vrbanic, I.

    2002-01-01

    The potential for common cause failures in systems that perform critical functions has been recognized as very important contributor to risk associated with operation of nuclear power plants. Consequentially, modeling of common cause failures (CCF) in fault trees has become one among the essential elements in any probabilistic safety assessment (PSA). Detailed and realistic representation of CCF potential in fault tree structure is sometimes very challenging task. This is especially so in the cases where a common cause group involves more than two components. During the last ten years the difficulties associated with this kind of modeling have been overcome to some degree by development of integral PSA tools with high capabilities. Some of them allow for the definition of CCF groups and their automated expanding in the process of Boolean resolution and generation of minimal cutsets. On the other hand, in PSA models developed and run by more traditional tools, CCF-potential had to be modeled in the fault trees explicitly. With explicit CCF modeling, fault trees can grow very large, especially in the cases when they involve CCF groups with 3 or more members, which can become an issue for the management of fault trees and basic events with traditional non-integral PSA models. For these reasons various simplifications had to be made. Speaking in terms of an overall PSA model, there are also some other issues that need to be considered, such as maintainability and accessibility of the model. In this paper a comparison is made between the two approaches to CCF modeling. Analysis is based on a full-scope Level 1 PSA model for internal initiating events that had originally been developed by a traditional PSA tool and later transferred to a new-generation PSA tool with automated CCF modeling capabilities. Related aspects and issues mentioned above are discussed in the paper. (author)

  10. Accelerated reliability demonstration under competing failure modes

    International Nuclear Information System (INIS)

    Luo, Wei; Zhang, Chun-hua; Chen, Xun; Tan, Yuan-yuan

    2015-01-01

    The conventional reliability demonstration tests are difficult to apply to products with competing failure modes due to the complexity of the lifetime models. This paper develops a testing methodology based on the reliability target allocation for reliability demonstration under competing failure modes at accelerated conditions. The specified reliability at mission time and the risk caused by sampling of the reliability target for products are allocated for each failure mode. The risk caused by degradation measurement fitting of the target for a product involving performance degradation is equally allocated to each degradation failure mode. According to the allocated targets, the accelerated life reliability demonstration test (ALRDT) plans for the failure modes are designed. The accelerated degradation reliability demonstration test plans and the associated ALRDT plans for the degradation failure modes are also designed. Next, the test plan and the decision rules for the products are designed. Additionally, the effects of the discreteness of sample size and accepted number of failures for failure modes on the actual risks caused by sampling for the products are investigated. - Highlights: • Accelerated reliability demonstration under competing failure modes is studied. • The method is based on the reliability target allocation involving the risks. • The test plan for the products is based on the plans for all the failure modes. • Both failure mode and degradation failure modes are considered. • The error of actual risks caused by sampling for the products is small enough

  11. Somatic versus cognitive symptoms of depression as predictors of all-cause mortality and health status in chronic heart failure

    DEFF Research Database (Denmark)

    Schiffer, Angélique A; Pelle, Aline J; Smith, Otto R F

    2009-01-01

    Depression is a predictor of adverse health outcomes in chronic heart failure (CHF), but it is not known whether specific symptoms drive this relationship. We examined the impact of somatic/affective, cognitive/affective, and total depressive symptoms on all-cause mortality and health status in CHF....

  12. 99mTc-HDP Bone Scan Findings of Acute Rhabdomyolysis of Lumbar Multifidus and Thigh Muscles and Bone Scan and US Signs of Acute Tubular Necrosis in Excessive Rabbit's Leaping: A Case Report

    International Nuclear Information System (INIS)

    Bahk, Yong Whee; Kim, Jang Min

    2008-01-01

    Marked rhabdomyolysis (RML) complicated by acute tubular necrosis is not a rare disease. It is characterized by disintegration of skeletal muscle fibers due to a variety of causes including excessive physical exercise, trauma, operation, infection, bed-ridden life, alcohol, drugs, toxins, exhaustion and others. We report a case of RML with acute renal failure studied using magnification bone scan which specifically identified the muscles injured by excessive rabbit's leap. The injured muscles recognized were the multifidus of the lumbar spine and the anterior and posterior muscle groups of the thigh. In addition, 99 mTc-HDP bone scan findings of acute tubular necrosis correlated with that of the sonographic signs are described. Patient was treated simply with normal saline hydration and bed rest and uneventfully recovered to be discharged on the fourth hospital day. Lab data on the final hospital day: LDH=20 IU/L (normalized) and CPK=600 IU/L (still higher than normal), BUN=14.2 mg/dl (normalized) and creatinin=1.5 mg/dl (normalized) GOT=20 mg/dl (normalized) and GPT=72 mg/dl (higher than normal), respectively

  13. Unexpected causes of pulmonary hypertension in a previously healthy Thai rural man with right-sided heart failure

    OpenAIRE

    Angkananard, Teeranan; Chonmaitree, Piyanant; Petborom, Pichaya

    2014-01-01

    Patient Male, 52 Final Diagnosis: Pulmonary hypertension Symptoms: Diarrhea • dyspnea • jaundice Medication: — Clinical Procedure: — Specialty: Endocrinology and Metabolic Objective: Unusual clinical course Background: Hyperthyroidism is one of the important causes of high-output failure and reversible pulmonary artery hypertension. Severe pulmonary artery hypertension is rarely found in associated with hyperthyroidism due to the small number of cases reported. We present an interesting case ...

  14. Development of delayed radiation necrosis

    International Nuclear Information System (INIS)

    Ohara, ShigFeki; Takagi, Terumasa; Shibata, Taichiro; Nagai, Hajime.

    1983-01-01

    The authors discussed the developing process of delayed radiation necrosis of the brain from the case of a 42-year-old female who developed intracranial hypertension and left hemiparesis 5 and a half years after radiotherapy for pituitary adenoma. The initial sign of radiation necrosis was from a CT scan taken 3 and a half years after radiotherapy showing an irregular low density lesion in the right temporal lobe. CT scan 2 years later demonstrated displacement of the midline structures to the left and a larger low density lesion with partially high density in the right MCA territory that was enhanced with intravenous contrast medium. Recovery after a right temporal lobectomy and administration of steroid hormone were uneventful. Eight months later there were no signs of raised intracranial pressure nor of neurological deficits. Tissues obtained from the right temporal lobe at lobectomy revealed the characteristic changes of delayed radiation necrosis; a mixture of fresh, recent, and old vascular lesions in the same specimen. From these findings, it was speculated that delayed radiation necrosis might initially occur within several years after radiotherapy and might gradually take a progressive and extended course, even in cases whose clinical symptoms develop much later. (author)

  15. Image and Substance Failures in Regional Organisations: Causes, Consequences, Learning and Change?

    Directory of Open Access Journals (Sweden)

    Meng Hsuan Chou

    2016-08-01

    Full Text Available States often pool their sovereignty, capacity and resources to provide regionally specific public goods, such as security or trade rules, and regional organisations play important roles in international relations as institutions that attempt to secure peace and contribute to achieving other similar global policy goals. We observe failures occurring in these arrangements and activities in two areas: substance and image. To analytically account for this, we distinguish four modes of substance and image change and link these to specific types of failure and (lack of learning. To empirically ground and test our assumptions, we examine instances of image failure in ASEAN (political/security policy and substantive policy failure in EU labour migration policy. In so doing, this article contributes to several different fields of study and concepts that have hitherto rarely engaged with one another: analyses of policy failure from public policy, and regional integration concerns from area studies and international relations. We conclude with suggestions for ways forward to further analyse and understand failures at the international and supranational levels.

  16. Joint disorder; a contributory cause to reproductive failure in beef bulls?

    Directory of Open Access Journals (Sweden)

    Ekman Stina

    2007-11-01

    Full Text Available Abstract The lame sire, unsound for breeding, can cause substantial economic loss due to reduced pregnancies in the beef-producing herd. To test the hypothesis that joint disorder is a possible cause of infertility in beef sires, right and left hind limb bones from 34 beef sires were examined postmortem to identify lesions in the femorotibial, femoropatellar (stifle, tarsocrural, talocalcaneus, and proximal intertarsal (tarsal joints. The bulls were slaughtered during or after the breeding season due to poor fertility results. Aliquots of the cauda epididymal contents taken postmortem from 26 bulls were used for sperm morphology evaluation. As a control, hind limbs (but no semen samples from 11 beef bulls with good fertility results were included. Almost all infertile bulls (30/34 had lesions in at least one joint. Twenty-eight bulls (28/30, 93% had lesions in the stifle joint, and 24 (24/28, 86% of these were bilateral. Fourteen bulls (14/30, 47% had lesions in the tarsal joint, and 10 (10/14, 71% of these were bilateral. Four bulls (4/34, 12% had no lesions, three bulls (3/34, 9% had mild osteoarthritis (OA, 5 (5/34, 15% moderate OA, 17 (17/34, 50% severe OA and 5 (5/34, 15% deformed OA. Almost all OA lesions (97% were characterized as lesions secondary to osteochondrosis dissecans. All the bulls with satisfactory sperm morphology (n = 12/34 had joint lesions, with mostly severe or deformed bilateral lesions (83%. Consequently, the most likely cause of infertility in these 12 bulls was joint disease. Almost all control bulls (10/11 had OA lesions, but most of them were graded as mild (55% or moderate (36%. None of the control bulls had severe lesions or deformed OA. We suggest that joint lesions should be taken into consideration as a contributory cause of reproductive failure in beef sires without symptoms of lameness.

  17. Estimating flood inundation caused by dam failures

    Energy Technology Data Exchange (ETDEWEB)

    Mocan, N. [Crozier and Associates Inc., Collingwood, ON (Canada); Joy, D.M. [Guelph Univ., ON (Canada). School of Engineering; Rungis, G. [Grand River Conservation Authority, Cambridge, ON (Canada)

    2006-01-15

    Recent advancements in modelling inundation due to dam failures have allowed easier and more illustrative analyses of potential outcomes. This paper described new model and mapping capabilities available using the HEC-RAS hydraulic model in concert with geographic information systems (GIS). The study area was the upper reaches of Canagagigue Creek and the Woolwich Dam near Elmira, Ontario. A hydraulic analysis of a hypothetical dam failure was developed based on the summer probable maximum flood (PMF) event. Limits extended from Woolwich Dam to downstream of the Town of Elmira. An incoming summer PMF hydrograph was set as the upstream boundary condition in the upstream model. Simulation parameters include simulation time-step; implicit weighting factor; water surface calculation tolerance; and output calculation interval. Peak flows were presented, as well as corresponding flood inundation results through the Town of Elmira. The hydraulic model results were exported to a GIS in order to develop inundation maps for emergency management planning. Results from post-processing included inundation maps for each of the simulated time-steps as well as an inundation animation for the duration of the dam breach. It was concluded that the modelling tools presented in the study can be applied to other dam safety assessment projects in order to develop effective and efficient emergency preparedness plans through public consultation and the establishment of impact zones. 1 tab., 2 figs.

  18. Diarachidonoylphosphoethanolamine induces necrosis/necroptosis of malignant pleural mesothelioma cells.

    Science.gov (United States)

    Kaku, Yoshiko; Tsuchiya, Ayako; Kanno, Takeshi; Nakano, Takashi; Nishizaki, Tomoyuki

    2015-09-01

    The present study investigated 1,2-diarachidonoyl-sn-glycero-3-phosphoethanolamine (DAPE)-induced cell death in malignant pleural mesothelioma (MPM) cells. DAPE reduced cell viability in NCI-H28, NCI-H2052, NCI-H2452, and MSTO-211H MPM cell lines in a concentration (1-100μM)-dependent manner. In the flow cytometry using propidium iodide (PI) and annexin V (AV), DAPE significantly increased the population of PI-positive and AV-negative cells, corresponding to primary necrosis, and that of PI-positive and AV-positive cells, corresponding to late apoptosis/secondary necrosis, in NCI-H28 cells. DAPE-induced reduction of NCI-H28 cell viability was partially inhibited by necrostatin-1, an inhibitor of RIP1 kinase to induce necroptosis, or knocking-down RIP1. DAPE generated reactive oxygen species (ROS) followed by disruption of mitochondrial membrane potentials in NCI-H28 cells. DAPE-induced mitochondrial damage was attenuated by cyclosporin A, an inhibitor of cyclophilin D (CypD). DAPE did not affect expression and mitochondrial localization of p53 protein in NCI-H28 cells. DAPE significantly decreased intracellular ATP concentrations in NCI-H28 cells. Overall, the results of the present study indicate that DAPE induces necroptosis and necrosis of MPM cells; the former is mediated by RIP1 kinase and the latter is caused by generating ROS and opening CypD-dependent mitochondrial permeability transition pore, to reduce intracellular ATP concentrations. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Periodontitis in Chronic Heart Failure.

    Science.gov (United States)

    Fröhlich, Hanna; Herrmann, Kristina; Franke, Jennifer; Karimi, Alamara; Täger, Tobias; Cebola, Rita; Katus, Hugo A; Zugck, Christian; Frankenstein, Lutz

    2016-08-01

    Periodontal disease has been associated with an increased risk of cardiovascular events. The purpose of our study was to investigate whether a correlation between periodontitis and chronic heart failure exists, as well as the nature of the underlying cause. We enrolled 71 patients (mean age, 54 ± 13 yr; 56 men) who had stable chronic heart failure; all underwent complete cardiologic and dental evaluations. The periodontal screening index was used to quantify the degree of periodontal disease. We compared the findings to those in the general population with use of data from the 4th German Dental Health Survey. Gingivitis, moderate periodontitis, and severe periodontitis were present in 17 (24%), 17 (24%), and 37 (52%) patients, respectively. Severe periodontitis was more prevalent among chronic heart failure patients than in the general population. In contrast, moderate periodontitis was more prevalent in the general population (P periodontal disease was not associated with the cause of chronic heart failure or the severity of heart failure symptoms. Six-minute walking distance was the only independent predictor of severe periodontitis. Periodontal disease is highly prevalent in chronic heart failure patients regardless of the cause of heart failure. Prospective trials are warranted to clarify the causal relationship between both diseases.

  20. Mechanisms of tumor necrosis in photodynamic therapy with a chlorine photosensitizer: experimental studies

    Science.gov (United States)

    Privalov, Valeriy A.; Lappa, Alexander V.; Bigbov, Elmir N.

    2011-02-01

    A photodynamic therapy experiment on 118 inbred white mice with transplanted Ehrlich's tumor (mouse mammary gland adenocarcinoma) is performed to reveal mechanisms of necrosis formation. In 7-10 days the tumor of 1-1.5 cm diameter is formed under skin at the injection point, and PDT procedure is applied. There were used a chlorine type photosensitizer RadachlorineTM and 662 nm wavelength diode laser. The drug is injected by intravenously at the dose of 40 mg/kg; the irradiation is executed in 2-2.5 hours at the surface dose of about 200 J/cm2. Each of the mice had a photochemical reaction in form of destructive changes at the irradiation region with subsequent development of dry coagulation necrosis. After rejection of the necrosis there occurred epithelization of defect tissues in a tumor place. Histological investigations were conducted in different follow-up periods, in 5 and 30 min, 1, 3, 6, and 12 hours, 1, 3, 7 and 28 days after irradiation. They included optical microscopy, immune marker analysis, morphometry with measurements of volume density of epithelium, tumor stroma and necroses, vascular bed. The investigations showed that an important role in damaging mechanisms of photodynamic action belongs to hypoxic injuries of tumor mediated by micro vascular disorders and blood circulatory disturbances. The injuries are formed in a few stages: microcirculation angiospasm causing vessel paresis, irreversible stases in capillaries, diapedetic hemorrhages, thromboses, and thrombovasculitis. It is marked mucoid swelling and fibrinoid necrosis of vascular tissue. Progressive vasculitises result in total vessel obliteration and tumor necrosis.

  1. Fuel pin failure root causes and power distribution gradients in WWER cores

    International Nuclear Information System (INIS)

    Mikus, J.

    2008-01-01

    The purpose of this work is to investigate the influence of some core heterogeneities and reactor construction materials on space power distribution in WWER type cores, especially from viewpoint of the values and gradient occurrence that could result in static loads with some consequences, e.g., fuel pin (FP) or fuel assembly (FA) bowing and possible contribution to the FP failure root causes. Presented information were obtained by means of experiments on research reactor LR-0 concerning the: 1) Power distribution estimation on pellet surface of the FPs neighbouring a FP containing gadolinium (Gd 2 O 3 ) burnable absorber integrated into fuel in WWER-440 and -1000 type cores; 2) Power distribution measurement in periphery FAs neighbouring the baffle in WWER-1000 type cores and 3) Power distribution in FAs neighbouring the control rod absorbing part in a WWER-440 type core. (author)

  2. Radiation necrosis of the mandible: a 10 year study. Part II. Dental factors; onset, duration and management of necrosis

    International Nuclear Information System (INIS)

    Murray, C.G.; Herson, J.; Daly, T.E.; Zimmerman, S.

    1980-01-01

    In a review of patients receiving radiation for cancer in the oral region the rate of radiation necrosis of the mandible was found to be similar for patients who had dental extractions before radiation therapy and for the remainder of the dentate population. It was suggested that diseased teeth should be removed prior to irradiation and sufficient healing time should be allowed. Teeth should not be extracted after irradiation. Dental prostheses can be provided for most irradiated patients if adequate care is exercised. The probability of necrosis commencing was highest three to twelve months after the start of therapy; it diminished gradually after that period. The duration of necrosis was depicted as an exponential curve with a constant probability of necrosis termination at each time point after onset. In 46.8% of the patients in study II (1971-1975), the necrosis was healed by conservative means. This was a significant increase over study I (1966-1969), and a complementary reduction in the necessity for surgical intervention was also found

  3. Your Heart Failure Healthcare Team

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Your Heart Failure Healthcare Team Updated:May 9,2017 Patients with ... to the Terms and Conditions and Privacy Policy Heart Failure • Home • About Heart FailureCauses and Risks for ...

  4. Planning Ahead: Advanced Heart Failure

    Science.gov (United States)

    ... Venous Thromboembolism Aortic Aneurysm More Planning Ahead: Advanced Heart Failure Updated:May 9,2017 An important part of ... Care This content was last reviewed May 2017. Heart Failure • Home • About Heart FailureCauses and Risks for ...

  5. Systematic analysis and prevention of human originated common cause failures in relation to maintenance activities at Finnish nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Laakso, K. [VTT Industrial Systems, Espoo (Finland)

    2006-12-15

    The focus in human reliability analysis of nuclear power plants has traditionally been on human performance in disturbance conditions. On the other hand, human maintenance failures and design deficiencies, remained latent in the system, have an impact on the severity of a disturbance, e.g. by disabling safety-related equipment on demand. Especially common cause failures (CCFs) of safety related systems can affect the core damage risk to a significant extent. The topic has been addressed in Finnish studies, where experiences of latent human errors have been searched and analysed systematically from the maintenance history stored in the the power plant information systems of the Loviisa and Olkiluoto NPPs. Both the single and multiple errors (CCFs) were classified in detail and documented as error and event reports. The human CCFs involved human, organisational and technical factors. The review of the analysed single and multiple errors showed that instrumentation and control and electrical equipment are more prone to human error caused failure events than the other maintenance objects. The review of the analysed experience showed that most errors stem from the refuelling and maintenance outage periods. More than half of the multiple errors from the outages remained latent to the power operating periods. The review of the analysed multiple errors showed that difficulties with small plant modifications and planning of maintenance and operability were significant sources of common cause failures. The most dependent human errors originating from small modifications could be reduced by a more tailored planning and coverage of their start-up testing programs. Improvements could also be achieved by identifying better in work planning from the operating experiences those complex or intrusive repair and preventive maintenance work tasks and actions which are prone to errors. Such uncertain cases in important equipment require a more tailored work planning of the installation

  6. Systematic analysis and prevention of human originated common cause failures in relation to maintenance activities at Finnish nuclear power plants

    International Nuclear Information System (INIS)

    Laakso, K.

    2006-12-01

    The focus in human reliability analysis of nuclear power plants has traditionally been on human performance in disturbance conditions. On the other hand, human maintenance failures and design deficiencies, remained latent in the system, have an impact on the severity of a disturbance, e.g. by disabling safety-related equipment on demand. Especially common cause failures (CCFs) of safety related systems can affect the core damage risk to a significant extent. The topic has been addressed in Finnish studies, where experiences of latent human errors have been searched and analysed systematically from the maintenance history stored in the the power plant information systems of the Loviisa and Olkiluoto NPPs. Both the single and multiple errors (CCFs) were classified in detail and documented as error and event reports. The human CCFs involved human, organisational and technical factors. The review of the analysed single and multiple errors showed that instrumentation and control and electrical equipment are more prone to human error caused failure events than the other maintenance objects. The review of the analysed experience showed that most errors stem from the refuelling and maintenance outage periods. More than half of the multiple errors from the outages remained latent to the power operating periods. The review of the analysed multiple errors showed that difficulties with small plant modifications and planning of maintenance and operability were significant sources of common cause failures. The most dependent human errors originating from small modifications could be reduced by a more tailored planning and coverage of their start-up testing programs. Improvements could also be achieved by identifying better in work planning from the operating experiences those complex or intrusive repair and preventive maintenance work tasks and actions which are prone to errors. Such uncertain cases in important equipment require a more tailored work planning of the installation

  7. Technical Basis for Evaluating Software-Related Common-Cause Failures

    Energy Technology Data Exchange (ETDEWEB)

    Muhlheim, Michael David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wood, Richard [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    The instrumentation and control (I&C) system architecture at a nuclear power plant (NPP) incorporates protections against common-cause failures (CCFs) through the use of diversity and defense-in-depth. Even for well-established analog-based I&C system designs, the potential for CCFs of multiple systems (or redundancies within a system) constitutes a credible threat to defeating the defense-in-depth provisions within the I&C system architectures. The integration of digital technologies into the I&C systems provides many advantages compared to the aging analog systems with respect to reliability, maintenance, operability, and cost effectiveness. However, maintaining the diversity and defense-in-depth for both the hardware and software within the digital system is challenging. In fact, the introduction of digital technologies may actually increase the potential for CCF vulnerabilities because of the introduction of undetected systematic faults. These systematic faults are defined as a “design fault located in a software component” and at a high level, are predominately the result of (1) errors in the requirement specification, (2) inadequate provisions to account for design limits (e.g., environmental stress), or (3) technical faults incorporated in the internal system (or architectural) design or implementation. Other technology-neutral CCF concerns include hardware design errors, equipment qualification deficiencies, installation or maintenance errors, instrument loop scaling and setpoint mistakes.

  8. Bile acids induce necrosis in pancreatic stellate cells dependent on calcium entry and sodium‐driven bile uptake

    Science.gov (United States)

    Jakubowska, Monika A.; Gerasimenko, Julia V.; Gerasimenko, Oleg V.; Petersen, Ole H.

    2016-01-01

    Key points Acute biliary pancreatitis is a sudden and severe condition initiated by bile reflux into the pancreas.Bile acids are known to induce Ca2+ signals and necrosis in isolated pancreatic acinar cells but the effects of bile acids on stellate cells are unexplored.Here we show that cholate and taurocholate elicit more dramatic Ca2+ signals and necrosis in stellate cells compared to the adjacent acinar cells in pancreatic lobules; whereas taurolithocholic acid 3‐sulfate primarily affects acinar cells.Ca2+ signals and necrosis are strongly dependent on extracellular Ca2+ as well as Na+; and Na+‐dependent transport plays an important role in the overall bile acid uptake in pancreatic stellate cells.Bile acid‐mediated pancreatic damage can be further escalated by bradykinin‐induced signals in stellate cells and thus killing of stellate cells by bile acids might have important implications in acute biliary pancreatitis. Abstract Acute biliary pancreatitis, caused by bile reflux into the pancreas, is a serious condition characterised by premature activation of digestive enzymes within acinar cells, followed by necrosis and inflammation. Bile acids are known to induce pathological Ca2+ signals and necrosis in acinar cells. However, bile acid‐elicited signalling events in stellate cells remain unexplored. This is the first study to demonstrate the pathophysiological effects of bile acids on stellate cells in two experimental models: ex vivo (mouse pancreatic lobules) and in vitro (human cells). Sodium cholate and taurocholate induced cytosolic Ca2+ elevations in stellate cells, larger than those elicited simultaneously in the neighbouring acinar cells. In contrast, taurolithocholic acid 3‐sulfate (TLC‐S), known to induce Ca2+ oscillations in acinar cells, had only minor effects on stellate cells in lobules. The dependence of the Ca2+ signals on extracellular Na+ and the presence of sodium–taurocholate cotransporting polypeptide (NTCP) indicate a Na

  9. Defense-in-depth for common cause failure of nuclear power plant safety system software

    International Nuclear Information System (INIS)

    Tian Lu

    2012-01-01

    This paper briefly describes the development of digital I and C system in nuclear power plant, and analyses the viewpoints of NRC and other nuclear safety authorities on Software Common Cause Failure (SWCCF). In view of the SWCCF issue introduced by the digitized platform adopted in nuclear power plant safety system, this paper illustrated a diversified defence strategy for computer software and hardware. A diversified defence-in-depth solution is provided for digital safety system of nuclear power plant. Meanwhile, analysis on problems may be faced during application of nuclear safety license are analyzed, and direction of future nuclear safety I and C system development are put forward. (author)

  10. Preservation of Skin Integrity in Heart Failure

    OpenAIRE

    DEMİR BARUTCU, Canan

    2018-01-01

    Congestive heart failure is an international health problem with its high incidence, prevalence, morbidity and mortality rates. Congestive heart failure is the most common reason of hospitalization in patients older than 65 and it causes more than a million hospitalizations a year. Patients with congestive heart failure experience a number of complications due to physiopathologic reasons, side effects of drugs, accompanying comorbid diseases and limitations caused by congestive heart failure....

  11. Avascular necrosis of bone complicating corticosteroid replacement therapy.

    OpenAIRE

    Williams, P L; Corbett, M

    1983-01-01

    Two patients who developed widespread severe avascular necrosis of bone while on steroid replacement therapy are described. One, a diabetic, underwent yttrium-90 pituitary ablation for retinopathy and developed avascular necrosis within 18 months of starting prednisolone. The other, who had Addison's disease, developed avascular necrosis within 14 months of starting cortisol replacement therapy. Both cases came to bilateral total hip replacement.

  12. Tracheal stoma necrosis: a case repor

    Directory of Open Access Journals (Sweden)

    Pak S

    2017-04-01

    Full Text Available Acute tracheal dilatation, due to an overinflated cuff, has been reported early in the course of mechanical ventilation through an endotracheal tube. Tracheal stoma necrosis is a rare complication, but such can accompany acute tracheal dilation. Herein, we report a case of tracheal necrosis 9 days following tracheostomy placement in a 71-year old woman associated with overinflation of the tracheal tube cuff. This case report aims to 1 add to the scant body of knowledge about the diagnosis and management for the patients with tracheal stoma necrosis and 2 raise awareness for error-traps in interpreting diagnostic images, specifically satisfaction of search error, inattentional blindness error, and alliterative error.

  13. Association of myocardial cell necrosis with experimental cardiac hypertrophy

    Energy Technology Data Exchange (ETDEWEB)

    Revis, N W; Cameron, A J.V.

    1979-01-01

    Cardiac hypertrophy was induced in rabbits by injecting thyroxime or isoprenaline, or by surgically constricting the abdominal aorta. An increase in heart weight was associated with a change in the ratios of bound to free forms of five lysosomal enzymes, a change in serum creatine phosphokinase and lactate dehydrogenase, and a change in the morphology of the myocardial cells. Isoprenaline treatment for 5 days induced a maximal change in heart weight, in the ratio of lysosomal enzymes, and in the serum enzymes. Thyroxine treatment was required for 15 days before maximal changes in heart weight, ratio, and serum enzymes were observed. In contrast, coarctation of the aorta caused a progressive change in heart weight, in the ratio of lysosomal enzymes, and in serum enzymes. These results suggest that necrosis of the myocardial cells does indeed accompany cardiac hypertrophy. It was further observed that autophagosomes, degenerating mitochondria in the myocardial cells during the induction of cardiac hypertrophy, and myofibril lysis were found, all of which confirms the suggestion of myocardial cell necrosis in the experimentally enlarged heart.

  14. Skin Necrosis from Intra-articular Hyaluronic Acid Injection.

    Science.gov (United States)

    Kim, Whan B; Alhusayen, Raed O

    2015-01-01

    Tissue necrosis is a rare yet potentially serious complication of intra-articular (IA) hyaluronic acid (HA) injections for treatment of knee osteoarthritis. To report a case of a patient with cutaneous necrosis after IA HA injection for treatment of knee osteoarthritis, presenting as a livedoid violaceous patch on the right knee. We report a case of cutaneous necrosis as a rare complication of IA HA injection for treatment of knee osteoarthritis. A literature review was undertaken of similar cases. Use of HA IA injections in the treatment of osteoarthritis can result in similar skin necrosis at uncommon anatomic locations corresponding to the site of HA injection. Although tissue necrosis is a rare complication, physicians need to be aware of this possibility as a complication of HA IA injections in the treatment of osteoarthritis and should be mindful of potential treatment options to manage this adverse event. © 2014 Canadian Dermatology Association.

  15. Fulminant hepatic failure in children: Etiology, histopathology and MDCT findings

    International Nuclear Information System (INIS)

    Cakir, Banu; Kirbas, Ismail; Demirhan, Beyhan; Tarhan, Nefise Cagla; Bozkurt, Alper; Ozcay, Figen; Coskun, Mehmet

    2009-01-01

    Introduction: The purpose of this study is to determine the etiologies, histopathology and MDCT findings of children with fulminant hepatic failure admitted to our institution. Materials and methods: Between June 2004 and November 2006, 15 children with fulminant hepatic failure who underwent MDCT were included retrospectively in this study. Twelve patients had liver biopsies. The patients were divided into three groups as hyperacute (Group I), acute (Group II) and subacute (Group III) depending on onset of hepatic encephalopathy. Results: Hepatitis A in 4 patients, non-A, non-E hepatitis in 4; mushroom poisoning in 3; fulminant Wilson's disease in 2; autoimmune hepatitis in 1; and both hepatitis B and toxic hepatitis (with leflunomide treatment) in 1 patient were detected. MDCT of all three groups revealed diffuse reduction in hepatic attenuation in 11 patients; ascites in 9; periportal edema in 6; edema of gallbladder wall in 6; splenomegaly in 6; heterogeneous hepatic parenchyma in 6; hepatomegaly in 3; irregular contours of liver in 2; multiple micronodules in 1 and necrotic areas and regeneration in liver parenchyma in 2 patients. Histopathologic evaluation of liver biopsies showed massive hepatic necrosis, inflammatory cell infiltration and ductular proliferation in 8 patients, periportal edema in 6, edema of gallbladder wall in 5, regenerating nodules and fibrous septa consistent with cirrhotic pattern in 2, and regenerating nodules and necrotic areas in 2 patients. Conclusion: The most common MDCT findings in fulminant hepatic failure were diffuse reduction in hepatic attenuation and ascites. Massive hepatic necrosis was the most common histopathologic finding.

  16. Fulminant hepatic failure in children: Etiology, histopathology and MDCT findings

    Energy Technology Data Exchange (ETDEWEB)

    Cakir, Banu [Baskent University Faculty of Medicine Department of Radiology, Fevzi Cakmak Cd. 10, Sok. No: 45, Bahcelievler, Ankara 06490 (Turkey)], E-mail: banutopcu@yahoo.com; Kirbas, Ismail [Baskent University Faculty of Medicine Department of Radiology, Fevzi Cakmak Cd. 10, Sok. No: 45, Bahcelievler, Ankara 06490 (Turkey)], E-mail: drismailk@yahoo.com; Demirhan, Beyhan [Baskent University Faculty of Medicine Department of Pathology, Fevzi Cakmak Cd. 10, Sok. No: 45, Bahcelievler, Ankara 06490 (Turkey)], E-mail: beyhand@baskent-ank.edu.tr; Tarhan, Nefise Cagla [Baskent University Faculty of Medicine Department of Radiology, Fevzi Cakmak Cd. 10, Sok. No: 45, Bahcelievler, Ankara 06490 (Turkey)], E-mail: caglat@gmail.com; Bozkurt, Alper [Baskent University Faculty of Medicine Department of Radiology, Fevzi Cakmak Cd. 10, Sok. No: 45, Bahcelievler, Ankara 06490 (Turkey)], E-mail: abozkurt78@hotmail.com; Ozcay, Figen [Baskent University Faculty of Medicine Department of Pediatric Gastroenterology, Fevzi Cakmak Cd. 10, Sok. No: 45, Bahcelievler, Ankara 06490 (Turkey)], E-mail: fozcay@baskent.edu.tr; Coskun, Mehmet [Baskent University Faculty of Medicine Department of Radiology, Fevzi Cakmak Cd. 10, Sok. No: 45, Bahcelievler, Ankara 06490 (Turkey)], E-mail: mcoskun@baskent-ank.edu.tr

    2009-11-15

    Introduction: The purpose of this study is to determine the etiologies, histopathology and MDCT findings of children with fulminant hepatic failure admitted to our institution. Materials and methods: Between June 2004 and November 2006, 15 children with fulminant hepatic failure who underwent MDCT were included retrospectively in this study. Twelve patients had liver biopsies. The patients were divided into three groups as hyperacute (Group I), acute (Group II) and subacute (Group III) depending on onset of hepatic encephalopathy. Results: Hepatitis A in 4 patients, non-A, non-E hepatitis in 4; mushroom poisoning in 3; fulminant Wilson's disease in 2; autoimmune hepatitis in 1; and both hepatitis B and toxic hepatitis (with leflunomide treatment) in 1 patient were detected. MDCT of all three groups revealed diffuse reduction in hepatic attenuation in 11 patients; ascites in 9; periportal edema in 6; edema of gallbladder wall in 6; splenomegaly in 6; heterogeneous hepatic parenchyma in 6; hepatomegaly in 3; irregular contours of liver in 2; multiple micronodules in 1 and necrotic areas and regeneration in liver parenchyma in 2 patients. Histopathologic evaluation of liver biopsies showed massive hepatic necrosis, inflammatory cell infiltration and ductular proliferation in 8 patients, periportal edema in 6, edema of gallbladder wall in 5, regenerating nodules and fibrous septa consistent with cirrhotic pattern in 2, and regenerating nodules and necrotic areas in 2 patients. Conclusion: The most common MDCT findings in fulminant hepatic failure were diffuse reduction in hepatic attenuation and ascites. Massive hepatic necrosis was the most common histopathologic finding.

  17. Association of the Endobiont Double-Stranded RNA Virus LRV1 With Treatment Failure for Human Leishmaniasis Caused by Leishmania braziliensis in Peru and Bolivia

    Science.gov (United States)

    Adaui, Vanessa; Lye, Lon-Fye; Akopyants, Natalia S.; Zimic, Mirko; Llanos-Cuentas, Alejandro; Garcia, Lineth; Maes, Ilse; De Doncker, Simonne; Dobson, Deborah E.; Arevalo, Jorge; Dujardin, Jean-Claude; Beverley, Stephen M.

    2016-01-01

    Cutaneous and mucosal leishmaniasis, caused in South America by Leishmania braziliensis, is difficult to cure by chemotherapy (primarily pentavalent antimonials [SbV]). Treatment failure does not correlate well with resistance in vitro, and the factors responsible for treatment failure in patients are not well understood. Many isolates of L. braziliensis (>25%) contain a double-stranded RNA virus named Leishmaniavirus 1 (LRV1), which has also been reported in Leishmania guyanensis, for which an association with increased pathology, metastasis, and parasite replication was found in murine models. Here we probed the relationship of LRV1 to drug treatment success and disease in 97 L. braziliensis–infected patients from Peru and Bolivia. In vitro cultures were established, parasites were typed as L. braziliensis, and the presence of LRV1 was determined by reverse transcription–polymerase chain reaction, followed by sequence analysis. LRV1 was associated significantly with an increased risk of treatment failure (odds ratio, 3.99; P = .04). There was no significant association with intrinsic SbV resistance among parasites, suggesting that treatment failure arises from LRV1-mediated effects on host metabolism and/or parasite survival. The association of LRV1 with clinical drug treatment failure could serve to guide more-effective treatment of tegumentary disease caused by L. braziliensis. PMID:26123565

  18. Strategies to reduce the apical necrosis in vitro multiplication and rooting of Pistachio

    Directory of Open Access Journals (Sweden)

    Mariela Cid

    2016-07-01

    Full Text Available The pistachio (Pistacia sp. is one of the least exploited fruit among the main causes is the high cost of plant material by the difficulties of propagation of the species. The propagation in vitro offers great potential for the industry of this species by multiplication scale of selected clones. The aim of this study was to control the apical necrosis of outbreaks in the in vitro propagation Pistachio. From young shoots of plants of this species kept in growing houses, proceeded to disinfection with sodium hypochlorite 1% for different times. The apical and axillary buds were established in the culture medium Murashige and Skoog (1962 modified and supplemented with 1 mg/L Metatopolina. Different types of bottles, number and type of explants and culture media formulations for two subcultures multiplication and rooting were evaluated. Glass flask of 200 ml capacity, and line proliferates DKW medium achieved the lowest values apical necrosis. In the multiplication phase values were low in all treatments tested no statistical difference between them compared to rooting where apical necrosis reached higher values. The average DKW and prolific lines obtained lower values. MS medium modified crop, favored the number of segments rooted and DKW (Driver and Kuniyuki, 1984 the number of segments that sprouted, the latter having lower incidence of apical necrosis.

  19. Pathophysiology of infectious hematopoietic necrosis virus disease in rainbow trout: hematological and blood chemical changes in moribund fish

    Science.gov (United States)

    Amend, D.F.; Smith, L.

    1975-01-01

    Infectious hematopoietic necrosis (IHN) is a rhabdoviral disease of rainbow trout (Salmo gairdneri). Trout were injected with IHNV, and various hematological and biochemical measurements of clinically ill fish were compared to uninfected controls. Infected fish had reduced corpuscular counts, hemoglobin, and packed cell volume, but normal mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration. The percentage of immature erythrocytes was increased, but the percentage of leukocytes was unchanged. Differential leukocyte counts showed a significant decrease in neutrophils, increase in lymphocytes, but no change in monocytes. Unidentifiable necrobiotic cells were prevelant in blood smears and hematopoietic tissue imprints. Plasma bicarbonate, chloride, calcium, phosphorus, bilirubin, and osmolality were significantly reduced, but plasma glucose and anterior kidney ascorbate were unchanged. Plasma pH increased and the alpha fractions of the serum proteins were altered. No change was found in plasma enzymes, except that a LDH isozyme was significantly increased. The alkali reserve was diminished and alterations in acid-base and fluid balance occurred. Death probably resulted from a severe electrolyte and fluid imbalance caused by renal failure.

  20. Identification and characterization of Nip, necrosis-inducing virulence protein of Erwinia carotovora subsp. carotovora.

    Science.gov (United States)

    Mattinen, Laura; Tshuikina, Marina; Mäe, Andres; Pirhonen, Minna

    2004-12-01

    Erwinia carotovora subsp. carotovora is a gram-negative bacterium that causes soft rot disease of many cultivated crops. When a collection of E. carotovora subsp. carotovora isolates was analyzed on a Southern blot using the harpin-encoding gene hrpN as probe, several harpinless isolates were found. Regulation of virulence determinants in one of these, strain SCC3193, has been characterized extensively. It is fully virulent on potato and in Arabidopsis thaliana. An RpoS (SigmaS) mutant of SCC3193, producing elevated levels of secreted proteins, was found to cause lesions resembling the hypersensitive response when infiltrated into tobacco leaf tissue. This phenotype was evident only when bacterial cells had been cultivated on solid minimal medium at low pH and temperature. The protein causing'the cell death was purified and sequenced, and the corresponding gene was cloned. The deduced sequence of the necrosis-inducing protein (Nip) showed homology to necrosis- and ethylene-inducing elicitors of fungi and oomycetes. A mutant strain of E. carotovora subsp. carotovora lacking the nip gene showed reduced virulence in potato tuber assay but was unaffected in virulence in potato stem or on other tested host plants.

  1. Mecanismos del daño celular en la insuficiencia renal aguda Mechanisms of cell damage in acute renal failure

    Directory of Open Access Journals (Sweden)

    José Martínez

    1989-01-01

    Full Text Available

    Los mecanismos del da no celular en la insuficiencia renal aguda Incluyen alteraciones en la producción de energía, la permeabilidad celular y el transporte de calcio. Dichas alteraciones producen cambios progresivos en la estructura celular que pueden ser reversibles si desaparece la causa que llevó a la falla renal, excepto cuando se alcanza la fase final de la lesión de la membrana y se llega a necrosis celular. Este mismo fenómeno probablemente ocurre tambIén en situaciones clínicas.

    The mechanisms of cellular damage In acute renal failure Include alterations In energy production, cell membrane permeability and calcium transport. These changes lead to progressive damage of the whole cellular structure which In general can be reversible If the precipitating cause disappears, except when the final stages of cell membrane lesion take place and cellular necrosis has occurred. This phenomenon probably applies for the clinical settling as well.

  2. Bilateral avascular necrosis of the femoral head due to the use of heroin: A case report.

    Science.gov (United States)

    Ozkunt, Okan; Sarıyılmaz, Kerim; Sungur, Mustafa; Ilen, Ferhat; Dikici, Fatih

    2015-01-01

    Femoral head avascular necrosis is caused by disruption of the blood supply of the femoral head, which finally results in hip dysfunction. Non traumatic osteonecrosis may related with corticosteroid use, alcohol abuse, SLE, hemoglobinopathies or exposure to cytotoxic agents. But avascular necrosis of the femoral head (ANFH) due to heroin use is a rare condition. We report a patient with bilateral ANFH due to heroin use treated by simultaneous bilateral hip arthroplasty. 37 year-old male patient presented with bilateral hip pain that had been occurring for four years. The patient had no history of smoking, excessive drinking, using corticosteroid and the other drugs or trauma but used heroin for 10 years. In clinic and radiologic examination indicated advanced degenerative changes on both hip due to femoral head avascular necrosis. The patient was treated with simultaneous bilateral total hip arthroplasty. After 6 months postoperatively the active hip range of motion was painless. Avascular femoral head necrosis caused by the using of heroin is rare. Ultimately, osteonecrosis of the femoral head occurs through one final common pathway, which is decreased blood flow to the femoral head that leads bone ischemia and death. But it is still unknown that heroin's systemic effects. Intravenous drug use more as a serious problem for today. There is a need for comprehensive studies to demonstrate effects of heroin on bone and vascularity metabolism. Heroin use will be important problem for population. That's why is crucial to understand the effect of heroin. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Failure of endodontic treatment: The usual suspects.

    Science.gov (United States)

    Tabassum, Sadia; Khan, Farhan Raza

    2016-01-01

    Inappropriate mechanical debridement, persistence of bacteria in the canals and apex, poor obturation quality, over and under extension of the root canal filling, and coronal leakage are some of the commonly attributable causes of failure. Despite the high success rate of endodontic treatment, failures do occur in a large number of cases and most of the times can be attributed to the already stated causes. With an ever increasing number of endodontic treatments being done each day, it has become imperative to avoid or minimize the most fundamental of reasons leading to endodontic failure. This paper reviews the most common causes of endodontic failure along with radiographic examples.

  4. First report of natural infection of Vigna mungo var. silvestris L. by Groundnut bud necrosis virus, a tospovirus

    Directory of Open Access Journals (Sweden)

    Mohammad AKRAM

    2010-09-01

    Full Text Available In the autumn of 2008, Vigna mungo var. silvestris growing in the experimental field of the Indian Institute of Pulses Research, Kanpur, India, showed chlorosis around some lateral veins and vein branches (mainly near the leaflet margin, downward curling of the leaf margins, necrosis of the stems and petioles, and twisting of the leaflets. Disease incidence was 20%. Symptoms indicated that the cause was Groundnut bud necrosis virus. The virus was identified on the basis of the symptoms on the diagnostic host, and the reverse transcription polymerase chain reaction (RT-PCR using specific primers of the NSm and NP genes. To our knowledge this is the first report of Groundnut bud necrosis virus on V. mungo var. silvestris.

  5. Ovarian function after autologous bone marrow transplantation in childhood: high-dose busulfan is a major cause of ovarian failure.

    Science.gov (United States)

    Teinturier, C; Hartmann, O; Valteau-Couanet, D; Benhamou, E; Bougneres, P F

    1998-11-01

    We studied pubertal status and ovarian function in 21 girls aged 11-21 years who had earlier received 1.2-13 years (median 7 years) high-dose chemotherapy and autologous BMT without TBI for malignant tumors. Ten of them were given busulfan (600 mg/m2) and melphalan (140 mg/m2) with or without cyclophosphamide (3.6 g/m2). Eleven others did not receive busulfan. Twelve girls (57%) had clinical and hormonal evidence of ovarian failure. Among nine others who had completed normal puberty, six had normal gonadotropin levels, one had elevated gonadotropin levels and two had gonadotropin levels at the upper limit of normal. The 10 girls who received busulfan all developed severe and persistent ovarian failure. High-dose busulfan is therefore a major cause of ovarian failure even when given in the prepubertal period. These findings emphasize the need for long-term endocrine follow-up of these patients in order to initiate estrogen replacement therapy.

  6. High-Temperature Graphitization Failure of Primary Superheater Tube

    Science.gov (United States)

    Ghosh, D.; Ray, S.; Roy, H.; Mandal, N.; Shukla, A. K.

    2015-12-01

    Failure of boiler tubes is the main cause of unit outages of the plant, which further affects the reliability, availability and safety of the unit. So failure analysis of boiler tubes is absolutely essential to predict the root cause of the failure and the steps are taken for future remedial action to prevent the failure in near future. This paper investigates the probable cause/causes of failure of the primary superheater tube in a thermal power plant boiler. Visual inspection, dimensional measurement, chemical analysis, metallographic examination and hardness measurement are conducted as the part of the investigative studies. Apart from these tests, mechanical testing and fractographic analysis are also conducted as supplements. Finally, it is concluded that the superheater tube is failed due to graphitization for prolonged exposure of the tube at higher temperature.

  7. Precursor T-cell acute lymphoblastic leukemia presenting with bone marrow necrosis: a case report

    Directory of Open Access Journals (Sweden)

    Khoshnaw Najmaddin SH

    2012-10-01

    Full Text Available Abstract Introduction Bone marrow necrosis is a clinicopathological condition diagnosed most often at postmortem examination, but it is also seen during the course of malignancy and is not always associated with a poor prognosis. The morphological features of bone marrow necrosis are disruption of the normal marrow architecture and necrosis of myeloid tissue and medullary stroma. Non-malignant conditions associated with bone marrow necrosis are sickle cell anemia, infections, drugs (sulfasalazine, interferon α, all-trans retinoic acid, granulocyte colony-stimulating factor and fludarabine, disseminated intravascular coagulation, antiphospholipid antibody syndrome and acute graft versus host diseases. The malignant causes are leukemia, lymphoma and metastatic carcinomas. Herein we report the case of a patient with precursor T-cell acute lymphoblastic leukemia and bone marrow necrosis at initial presentation. Case presentation A 10-year-old Kurdish boy was presented with generalized bone pain and fever of 1 month’s duration which was associated with sweating, easy fatigability, nose bleeding, breathlessness and severe weight loss. On examination, we observed pallor, tachypnea, tachycardia, low blood pressure, fever, petechial hemorrhage, ecchymoses, tortuous dilated veins over the chest and upper part of abdomen, multiple small cervical lymph node enlargements, mildly enlarged spleen, palpable liver and gross abdominal distention. Blood analysis revealed pancytopenia and elevated lactate dehydrogenase and erythrocyte sedimentation rate. Imaging results showed mediastinal widening on a planar chest X-ray and diffuse focal infiltration of the axial bone marrow on magnetic resonance imaging of the lumbosacral vertebrae. Bone marrow aspiration and biopsy examination showed extensive bone marrow necrosis. Immunophenotyping analysis of the bone marrow biopsy confirmed T-cell acute lymphoblastic leukemia, as CD3 and terminal deoxynucleotidyl

  8. Acute Hepatopancreatic Necrosis Disease (AHPND) related microRNAs in Litopenaeus vannamei infected with AHPND-causing strain of Vibrio parahemolyticus.

    Science.gov (United States)

    Zheng, Zhihong; Aweya, Jude Juventus; Wang, Fan; Yao, Defu; Lun, Jingsheng; Li, Shengkang; Ma, Hongyu; Zhang, Yueling

    2018-05-08

    Acute hepatopancreatic necrosis disease (AHPND) has emerged as a major debilitating disease that causes massive shrimp death resulting in substantial economic losses in shrimp aquaculture. Given that several diseases and infections have been associated with microRNAs (miRNAs), we conducted a comparative transcriptomic analysis using the AHPND (VA) and non-AHPND (VN) strains of Vibrio parahemolyticus to identify miRNAs potentially involved in AHPND pathogenesis in Litopenaeus vannamei. A total of 83 miRNAs (47 upregulated and 36 downregulated) were significantly differentially expressed between the VA and VN challenged groups, while 222 target genes of these miRNAs were predicted. Functional enrichment analysis revealed that the miRNAs target genes were involved in multiple biological processes including metabolic pathways, amoebiasis, Vibrio cholerae infection etc. Finally, interaction network and qPCR (Real-time Quantitative PCR) analysis of 12 potential key AHPND-related miRNAs and their predicted target genes, revealed their possible involvement in modulating several immune-related processes in the pathogenesis of AHPND. We have shown using comparative transcriptomic analysis, miRNAs and their target genes that are responsive to AHPND V. parahemolyticus infection in shrimp, therefore suggesting their possible role in defense response to AHPND V. parahemolyticus infection.

  9. Avascular necrosis of the femoral head in HIV infected patients

    Directory of Open Access Journals (Sweden)

    Marcos Almeida Matos

    Full Text Available Avascular necrosis (AVN of the femoral head is an emerging complication in HIV infected patients. It has been suggested that the increased incidence of AVN in this population may be caused by an increased prevalence of predisposing factors for osteonecrosis, including protease inhibitors, hyperlipidemia, corticosteroid use, alcohol and intravenous drug abuse. The aim of this study was to assess the risk factors for avascular necrosis developing in the femoral head of HIV infected individuals. This study consisted of meta-analysis of the secondary data extracted from current literature. The selected articles allowed two study groups to be drawn up for comparison. Group 1 comprised 324 individuals infected by the HIV virus, who did not present femoral head AVN. Group 2 comprised 32 HIV positive patients, who presented femoral head AVN. The parameters used for analysis were as follows: age, gender, sexual preference, use of intravenous drugs, time of diagnosis, CD4+ cell count, use of antiretroviral agents and duration, serum cholesterol and serum triglycerides. The present study found a statistically significant association between hypertriglyceridemia, hypercholesterolemia, sexual preference and intravenous drug abuse. The authors concluded that femoral head osteonecrosis is associated with hyperlipidemia (hypercholesterolemia and hypertriglyceridemia and intravenous drug abuse. This study supports the hypothesis that protease inhibitors play a role in the development of osteonecrosis through a tendency to cause hyperlipidemia.

  10. ROLE OF THE MITOCHONDRION IN PROGRAMMED NECROSIS

    Directory of Open Access Journals (Sweden)

    Christopher eBaines

    2010-11-01

    Full Text Available In contrast to the programmed nature of apoptosis and autophagy, necrotic cell death has always been believed to be a random, uncontrolled process that leads to the accidental death of the cell. This dogma, however, is being challenged and the concept of necrosis also being programmed is gaining ground. In particular, mitochondria appear to play a pivotal role in the mediation of programmed necrosis. The purpose of this review, therefore, is to appraise the current concepts regarding the signaling mechanisms of programmed necrosis, with specific attention to the contribution of mitochondria to this process.

  11. Muscle necrosis in the extremities: evaluation with Tc-99m pyrophosphate scanning--a retrospective review

    International Nuclear Information System (INIS)

    Timmons, J.H.; Hartshorne, M.F.; Peters, V.J.; Cawthon, M.A.; Bauman, J.M.

    1988-01-01

    A retrospective review was done of 34 extremities studied between 1981 and 1985 with technetium-99m pyrophosphate scanning; 22 were subsequently amputated. Results of detailed pathologic examination or immediate postoperative examination of the resected extremity were available in 16 cases. In these cases, scanning had allowed correct prediction of the level of amputation and of the specific areas of muscle infarction in 13 cases. In the one case in which amputation was performed for infection rather than muscle necrosis, the lack of necrosis was correctly predicted with the scan. The limited results of this study indicate that the Tc-99m pyrophosphate scan allows the location of necrotic muscle to be predicted accurately and may therefore be a useful adjunct in determining the best level for ultimate amputation. Special caution is required in those cases in which muscle necrosis is due to acute causes (e.g., traumatic thrombosis) rather than chronic vascular disease

  12. Pill Properties that Cause Dysphagia and Treatment Failure

    Science.gov (United States)

    Fields, Jeremy; Go, Jorge T.; Schulze, Konrad S.

    2015-01-01

    Background Pills (tablets and capsules) are widely used to administer prescription drugs or to take supplements such as vitamins. Unfortunately, little is known about how much effort it takes Americans to swallow these various pills. More specifically, it is not known to what extent hard-to-swallow pills might affect treatment outcomes (eg, interfering with adherence to prescribed medications or causing clinical complications). It is also unclear which properties (eg, size, shape, or surface texture) Americans prefer or reject for their pills. To learn more about these issues, we interviewed a small group of individuals. Methods We invited individuals in waiting rooms of our tertiary health care center to participate in structured interviews about their pill-taking habits and any problems they have swallowing pills. We inquired which pill properties they believed caused swallowing problems. Participants scored capsules and pills of representative size, shape, and texture for swallowing effort and reported their personal preferences. Results Of 100 successive individuals, 99 participants completed the interview (65% women, mean age = 41 years, range = 23-77 years). Eighty-three percent took pills daily (mean 4 pills/d; 56% of those pills were prescribed by providers). Fifty-four percent of participants replied yes to the question, "Did you ever have to swallow a solid medication that was too difficult?" Four percent recounted serious complications: 1% pill esophagitis, 1% pill impaction, and 2% stopped treatments (antibiotic and prenatal supplement) because they could not swallow the prescribed pills. Half of all participants routinely resorted to special techniques (eg, plenty of liquids or repeated or forceful swallows). Sixty-one percent of those having difficulties cited specific pill properties: 27% blamed size (20% of problems were caused by pills that were too large whereas 7% complained about pills that were too small to sense); 12% faulted rough surface

  13. Predictive value of histologic tumor necrosis after radiation.

    Science.gov (United States)

    Chen, Y; Taghian, A G; Rosenberg, A E; O'Connell, J; Okunieff, P; Suit, H D

    2001-12-20

    Postsurgical evaluation of histologic changes of tumors after preoperative chemotherapy and/or radiotherapy has been a routine clinical practice of pathologists and oncologists. There appears to be secure evidence that the extent of tumor necrosis vs. viable tumor cells postchemotherapy is a clinically useful predictor of outcome. The significance of histologic tumor necrosis after radiotherapy, however, has not been clearly established and deserves further investigation. We investigated the correlation between histological extent of tumor necrosis, survival of tumor transplants, and radiation doses in an experimental model using three human tumor xenografts. Three human tumor cell lines were investigated: STS-26, SCC-21, and HGL-21. Tumors were grown subcutaneously in athymic nude mice and received external beam radiation of different doses. Tumors were excised 2 weeks postirradiation. One-half of the tumor was divided into 1-mm(3) fragments and transplanted to naive mice. The other half was examined for histologic tumor necrosis. Transplant survival was strongly correlated with radiation dose, TCD(p) (radiation dose that results in local tumor control in proportion, p, to irradiated tumors). In contrast, there was no clear association between transplant survival rate and the extent of tumor necrosis. The experimental model demonstrated a strong inverse correlation between radiation doses and tumor transplant survival. Histologic tumor necrosis did not correlate well with radiation doses or transplant survival rates. Despite common practices in histologic examination of tumors posttherapy, clinical interpretations and implications of histologic tumor necrosis after radiotherapy should be considered with caution. Copyright 2001 Wiley-Liss, Inc.

  14. Citrin deficiency: a novel cause of failure to thrive that responds to a high-protein, low-carbohydrate diet.

    Science.gov (United States)

    Dimmock, David; Kobayashi, Keiko; Iijima, Mikio; Tabata, Ayako; Wong, Lee-Jun; Saheki, Takeyori; Lee, Brendan; Scaglia, Fernando

    2007-03-01

    The proband was born at 36 weeks, appropriate for gestational age, to nonconsanguineous white parents. There was no evidence of hyperbilirubinemia or intrahepatic cholestasis in the neonatal period, and she had normal newborn screen results. She presented with 3 episodes of life-threatening bleeding and anemia. The diagnostic evaluation for her bleeding diathesis revealed an abnormal clotting profile with no biochemical evidence for hepatocellular damage. She was incidentally noted to have severe growth deceleration that failed to respond to 502 kJ/kg (120 kcal/kg) per day of protein-hydrolyzed formula. An extensive diagnostic workup for failure to thrive, which was otherwise normal, included plasma amino acid analysis that revealed hyperglutaminemia and citrulline levels within the reference range. Testing of a repeat sample revealed isolated hypercitrullinemia. No argininosuccinic acid was detected. Her ammonia level and urine orotic acid were within the reference ranges. Subsequent plasma amino acid analysis exhibited a profile suggestive of neonatal intrahepatic cholestasis caused by citrin deficiency with elevations in citrulline, methionine, and threonine. Western blotting of fibroblasts demonstrated citrin deficiency, and a deletion for exon 3 was found in the patient's coding DNA of the SLC25A13 gene. On the basis of the experience with adults carrying this condition, the patient was given a high-protein, low-carbohydrate diet. The failure to thrive and bleeding diathesis resolved. When compliance with the dietary prescription was relaxed, growth deceleration was again noted, although significant bleeding did not recur. This is the first report of an infant of Northern European descent with citrin deficiency. The later age at presentation with failure to thrive and bleeding diathesis and without obvious evidence of neonatal intrahepatic cholestasis expands the clinical spectrum of citrin deficiency. This case emphasizes the importance of continued dietary

  15. Do Foreign Language Learners Need Failures?

    Directory of Open Access Journals (Sweden)

    Joanna Kic-Drgas

    2016-06-01

    Full Text Available A lack of motivation, incomprehensible content and a high workload are only some of the causes leading to students’ failures in the learning process. Dealing with failures seems to have become a new core competence in the current world, which is why the definition and implementation of an appropriate strategy is essential for prospective learning results. The focus of the contribution is on the meaning of failure and sources of potential student failures in the foreign language learning at the university level. The results presented in the paper base on the survey conducted with English language students at Koszalin University of Technology. Students were asked to identify the field causing learning failures. The described survey delivers information about the sources of failures from learner’s point of view, which can be an incentive to develop and implement strategies to cope with failures in the ESP class.

  16. Giant cardiac fibroma: an unusual cause of failure to thrive.

    Science.gov (United States)

    Navarini, Susanne; Latzin, Philipp; Kadner, Alexander; Carrel, Thierry; Hutter, Damian

    2013-06-01

    Cardiac fibromas are extremely rare in the general pediatric population and may present with a wide spectrum of clinical signs, including life-threatening arrhythmias and sudden death. We report a 14-month-old boy who presented with failure to thrive as the only symptom. Echocardiography showed a large cardiac fibroma in the right ventricle. Cardiac magnetic resonance imaging confirmed the diagnosis. After complete surgical tumor resection, the boy showed normal catch-up growth. This case underlines the diversity of clinical features of cardiac tumors, which implies that they should be considered early in the differential diagnosis of infants with failure to thrive.

  17. Left atrial leiomyosarcoma as cause of heart failure

    International Nuclear Information System (INIS)

    Valdes Martin, Alexander

    2012-01-01

    The case of a 26 year-old patient with diagnosis of heart failure and presence of a mobile echogenic mass without calcification attached to the posterolateral area of the left atrium was reported. She underwent surgery and tissue examination evidenced a high-grade heart leiomyosarcoma. Postoperative course was satisfactory and her clinical state was rigorously monitored by oncology and heart specialists in the institution

  18. Widespread marrow necrosis during pregnancy

    International Nuclear Information System (INIS)

    Knickerbocker, W.J.; Quenville, N.F.

    1982-01-01

    Recently, a 22-year-old Caucasian female was referred to our Hospital two days post-partum. She had been feeling unwell during the last few days of her pregnancy and complained of multiple aches and pains, worst in the abdomen and lower back. Her admission platelet count was severely depressed and a bone biopsy showed extensive marrow necrosis with viable bony trabeculae. There was no evidence of vasculitis, vascular thrombosis, or malignancy. Widespread marrow necrosis in pregnancy followed by recovery, to our knowledge, has not been previously reported. (orig.)

  19. Skin Flap Necrosis After Mastectomy With Reconstruction: A Prospective Study.

    Science.gov (United States)

    Matsen, Cindy B; Mehrara, Babak; Eaton, Anne; Capko, Deborah; Berg, Anastasia; Stempel, Michelle; Van Zee, Kimberly J; Pusic, Andrea; King, Tari A; Cody, Hiram S; Pilewskie, Melissa; Cordeiro, Peter; Sclafani, Lisa; Plitas, George; Gemignani, Mary L; Disa, Joseph; El-Tamer, Mahmoud; Morrow, Monica

    2016-01-01

    Rates of mastectomy with immediate reconstruction are rising. Skin flap necrosis after this procedure is a recognized complication that can have an impact on cosmetic outcomes and patient satisfaction, and in worst cases can potentially delay adjuvant therapies. Many retrospective studies of this complication have identified variable event rates and inconsistent associated factors. A prospective study was designed to capture the rate of skin flap necrosis as well as pre-, intra-, and postoperative variables, with follow-up assessment to 8 weeks postoperatively. Uni- and multivariate analyses were performed for factors associated with skin flap necrosis. Of 606 consecutive procedures, 85 (14 %) had some level of skin flap necrosis: 46 mild (8 %), 6 moderate (1 %), 31 severe (5 %), and 2 uncategorized (0.3 %). Univariate analysis for any necrosis showed smoking, history of breast augmentation, nipple-sparing mastectomy, and time from incision to specimen removal to be significant. In multivariate models, nipple-sparing, time from incision to specimen removal, sharp dissection, and previous breast reduction were significant for any necrosis. Univariate analysis of only moderate or severe necrosis showed body mass index, diabetes, nipple-sparing mastectomy, specimen size, and expander size to be significant. Multivariate analysis showed nipple-sparing mastectomy and specimen size to be significant. Nipple-sparing mastectomy was associated with higher rates of necrosis at every level of severity. Rates of skin flap necrosis are likely higher than reported in retrospective series. Modifiable technical variables have limited the impact on rates of necrosis. Patients with multiple risk factors should be counseled about the risks, especially if they are contemplating nipple-sparing mastectomy.

  20. Hypopituitarism presenting as congestive heart failure

    Directory of Open Access Journals (Sweden)

    S Giri

    2017-01-01

    Full Text Available Sheehan's syndrome (SS develops as a result of ischemic pituitary necrosis due to severe postpartum hemorrhage and is characterized by various degrees of hypopituitarism. Although the occurrence of SS is now rare, it should still be considered in any woman with a history of peripartum hemorrhage who develops manifestations of pituitary hormone deficiency any time following the event. Appropriate hormone replacement therapy results in marked clinical improvement. We present an unusual case of SS in a young lady who continued to have normal menstruation after the index event, had two spontaneous pregnancies, and was diagnosed only 11 years later when she presented to us with acute heart failure.

  1. Dependent failures of diesel generators

    International Nuclear Information System (INIS)

    Mankamo, T.; Pulkkinen, U.

    1982-01-01

    This survey of dependent failures (common-cause failures) is based on the data of diesel generator failures in U. S. nuclear power plants as reported in Licensee Event Reports. Failures were classified into random and potentially dependent failures. All failures due to design errors, manufacturing or installation errors, maintenance errors, or deviations in the operational environment were classified as potentially dependent failures.The statistical dependence between failures was estimated from the relative portion of multiple failures. Results confirm the earlier view of the significance of statistical dependence, a strong dependence on the age of the diesel generator was found in each failure class excluding random failures and maintenance errors, which had a nearly constant frequency independent of diesel generator age

  2. The Process-Oriented Simulation (POS) model for common cause failures: recent progress

    International Nuclear Information System (INIS)

    Berg, H.P.; Goertz, R.; Schimetschka, E.; Kesten, J.

    2006-01-01

    A common-cause failure (CCF) model based on stochastic simulation has been developed to complement the established approaches and to overcome some of their shortcomings. Reflecting the models proximity to the CCF process it was called Process Oriented Simulation (POS) Model. In recent years, some progress has been made to render the POS model fit for practical applications comprising the development of parameter estimates and a number of test applications in areas where results were already available - especially from CCF benchmarks - and comparison can provide insights in strong and weak points of the different approaches. In this paper, a detailed description of the POS model is provided together with the approach to parameter estimation and representative test applications. It is concluded, that the POS model has a number of strengths - especially the feature to provide reasonable extrapolation to CCF groups with high degrees of redundancy - and thus a considerable potential to complement the insights obtained from existing modeling. (orig.)

  3. Risk factors for local failure requiring salvage neurosurgery after radiosurgery for brain metastases

    International Nuclear Information System (INIS)

    Weltman, Eduardo; Hanriot, Rodrigo de Morais; Prisco, Flavio Eduardo; Nadalin, Wladimir; Brandt, Reynaldo Andre; Moreira, Frederico Rafael

    2004-01-01

    Objective: the aim of this study is to select the risk factors for local failure requiring salvage neurosurgery in patients with brain metastases treated with stereotactic radiosurgery in a single institution. Methods: the follow-up of 123 patients, with 255 brain metastases treated with radiosurgery at the Radiation Oncology Department of the Hospital Israelita Albert Einstein from July 1993 to August 2001, was retrospectively analyzed. The criteria for salvage neurosurgery were tumor volume enlargement, or tumor persistence leading to severe neurological symptoms, life threatening situation or critical steroid dependence. We considered the case as local failure when the histopathologic evaluation showed morphologically preserved cancer cells (tumor recurrence, persistence or progression). We applied the Fisher's exact test to evaluate the statistical correlation between local failure and primary tumor histology, volume of the brain metastases, prescribed radiosurgery dose, and whole brain radiotherapy. Results: fourteen of 123 patients (11%) underwent salvage neurosurgery. Histology showed preserved cancer cells with necrosis and/or bleeding in 11 cases (9% of the total accrual), and only necrosis with or without bleeding (without preserved cancer cells) in three cases. The primary tumor histology among the 11 patients considered with active neoplasia was malignant melanoma in five cases (21% of the patients with melanoma), breast adenocarcinoma in three (16% of the patients with breast cancer), and other histology in the remaining three. Breast cancer diagnosis, non-elective whole brain irradiation, volume of the brain metastases, and the prescribed radiosurgery dose did not correlate with the risk of local failure. Patients treated with elective whole brain radiotherapy showed fewer local failures, when compared to all patients receiving whole brain radiotherapy, and to the patients not receiving this treatment, with incidence of failure in 4%,7% and 14

  4. Management of Postoperative Respiratory Failure.

    Science.gov (United States)

    Mulligan, Michael S; Berfield, Kathleen S; Abbaszadeh, Ryan V

    2015-11-01

    Despite best efforts, postoperative complications such as postoperative respiratory failure may occur and prompt recognition of the process and management is required. Postoperative respiratory failure, such as postoperative pneumonia, postpneumonectomy pulmonary edema, acute respiratory distress-like syndromes, and pulmonary embolism, are associated with high morbidity and mortality. The causes of these complications are multifactorial and depend on preoperative, intraoperative, and postoperative factors, some of which are modifiable. The article identifies some of the risk factors, causes, and treatment strategies for successful management of the patient with postoperative respiratory failure. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Implication of snail in metabolic stress-induced necrosis.

    Directory of Open Access Journals (Sweden)

    Cho Hee Kim

    2011-03-01

    Full Text Available Necrosis, a type of cell death accompanied by the rupture of the plasma membrane, promotes tumor progression and aggressiveness by releasing the pro-inflammatory and angiogenic cytokine high mobility group box 1. It is commonly found in the core region of solid tumors due to hypoxia and glucose depletion (GD resulting from insufficient vascularization. Thus, metabolic stress-induced necrosis has important clinical implications for tumor development; however, its regulatory mechanisms have been poorly investigated.Here, we show that the transcription factor Snail, a key regulator of epithelial-mesenchymal transition, is induced in a reactive oxygen species (ROS-dependent manner in both two-dimensional culture of cancer cells, including A549, HepG2, and MDA-MB-231, in response to GD and the inner regions of a multicellular tumor spheroid system, an in vitro model of solid tumors and of human tumors. Snail short hairpin (sh RNA inhibited metabolic stress-induced necrosis in two-dimensional cell culture and in multicellular tumor spheroid system. Snail shRNA-mediated necrosis inhibition appeared to be linked to its ability to suppress metabolic stress-induced mitochondrial ROS production, loss of mitochondrial membrane potential, and mitochondrial permeability transition, which are the primary events that trigger necrosis.Taken together, our findings demonstrate that Snail is implicated in metabolic stress-induced necrosis, providing a new function for Snail in tumor progression.

  6. Phylogeography of infectious haematopoietic necrosis virus in North America

    DEFF Research Database (Denmark)

    Kurath, G.; Garver, K.A.; Troyer, R.M.

    2003-01-01

    Infectious hematopoietic necrosis virus (IHNV) is a rhabdoviral pathogen that infects wild and cultured salmonid fish throughout the Pacific Northwest of North America. IHNV causes severe epidemics in young fish and can cause disease or occur asymptomatically in adults. In a broad survey of 323...... IHNV field isolates, sequence analysis of a 303 nucleotide variable region within the glycoprotein gene revealed a maximum nucleotide diversity of 8(.)6%, indicating low genetic diversity overall for this virus. Phylogenetic analysis revealed three major virus genogroups, designated U, M and L, which...... varied in topography and geographical range. Intragenogroup genetic. diversity measures indicated that the M genogroup had three- to fourfold more diversity than the other genogroups and suggested relatively rapid evolution of the M genogroup and stasis within the U genogroup. We speculate that factors...

  7. A Novel Composite PMMA-based Bone Cement with Reduced Potential for Thermal Necrosis.

    Science.gov (United States)

    Lv, Yang; Li, Ailing; Zhou, Fang; Pan, Xiaoyu; Liang, Fuxin; Qu, Xiaozhong; Qiu, Dong; Yang, Zhenzhong

    2015-06-03

    Percutaneous vertebroplasty (VP) and balloon kyphoplasty (BKP) are now widely used to treat patients who suffer painful vertebral compression fractures. In each of these treatments, a bone cement paste is injected into the fractured vertebral body/bodies, and the cement of choice is a poly(methyl methacrylate) (PMMA) bone cement. One drawback of this cement is the very high exothermic temperature, which, it has been suggested, causes thermal necrosis of surrounding tissue. In the present work, we prepared novel composite PMMA bone cement where microcapsules containing a phase change material (paraffin) (PCMc) were mixed with the powder of the cement. A PCM absorbs generated heat and, as such, its presence in the cement may lead to reduction in thermal necrosis. We determined a number of properties of the composite cement. Compared to the values for a control cement (a commercially available PMMA cement used in VP and BKP), each composite cement was found to have significantly lower maximum exothermic temperature, increased setting time, significantly lower compressive strength, significantly lower compressive modulus, comparable biocompatibility, and significantly smaller thermal necrosis zone. Composite cement containing 20% PCMc may be suitable for use in VP and BKP and thus deserves further evaluation.

  8. Failure probabilistic model of CNC lathes

    International Nuclear Information System (INIS)

    Wang Yiqiang; Jia Yazhou; Yu Junyi; Zheng Yuhua; Yi Shangfeng

    1999-01-01

    A field failure analysis of computerized numerical control (CNC) lathes is described. Field failure data was collected over a period of two years on approximately 80 CNC lathes. A coding system to code failure data was devised and a failure analysis data bank of CNC lathes was established. The failure position and subsystem, failure mode and cause were analyzed to indicate the weak subsystem of a CNC lathe. Also, failure probabilistic model of CNC lathes was analyzed by fuzzy multicriteria comprehensive evaluation

  9. Control rod trip failures; Salem 1, the cause, response, and potential fixes

    International Nuclear Information System (INIS)

    Hall, R.E.; Boccio, J.L.; Luckas, W.J.

    1984-01-01

    This chapter presents a systems and reliability analysis of recent nuclear reactor control rod failure-to-trip (or scram) events that have been experienced in the US commercial nuclear industry. The operational factors of hardware, procedures, and human error are considered in the analysis of transients without scram. The 1980 Browns Ferry 3 scram system failure is analyzed to contrast the two 1983 Salem 1 events. The details of the Salem control rod failure to trip are investigated and used to calculate the reactor protection system unavailabilities. The internal reactor trip breaker logic is reviewed as related to the Westinghouse DB-50 breaker application. The impact of test and maintenance on system challenges is discussed. It is concluded that although the failure to trip or scram represents a single class of initiators, the actual events of each transient are operationally unique and require individual human responses

  10. 4. Nuclear power plant component failures

    International Nuclear Information System (INIS)

    1990-01-01

    Nuclear power plant component failures are dealt with in relation to reliability in nuclear power engineering. The topics treated include classification of failures, analysis of their causes and impacts, nuclear power plant failure data acquisition and processing, interdependent failures, and human factor reliability in nuclear power engineering. (P.A.). 8 figs., 7 tabs., 23 refs

  11. Standard guide for corrosion-related failure analysis

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This guide covers key issues to be considered when examining metallic failures when corrosion is suspected as either a major or minor causative factor. 1.2 Corrosion-related failures could include one or more of the following: change in surface appearance (for example, tarnish, rust, color change), pin hole leak, catastrophic structural failure (for example, collapse, explosive rupture, implosive rupture, cracking), weld failure, loss of electrical continuity, and loss of functionality (for example, seizure, galling, spalling, swelling). 1.3 Issues covered include overall failure site conditions, operating conditions at the time of failure, history of equipment and its operation, corrosion product sampling, environmental sampling, metallurgical and electrochemical factors, morphology (mode) or failure, and by considering the preceding, deducing the cause(s) of corrosion failure. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibili...

  12. Reduced ovulation rate, failure to be mated and fertilization failure/embryo loss are the underlying causes of poor reproductive performance in juvenile ewes.

    Science.gov (United States)

    Edwards, Sara J; Smaill, Bronwyn; O'Connell, Anne R; Johnstone, Peter D; Stevens, David R; Quirke, Laurel D; Farquhar, Philip A; Juengel, Jennifer L

    2016-04-01

    A ewe that is mated as a juvenile (producing a lamb at 1 year of age) will produce an average of only 0.6 lambs to weaning, compared to an average of 1.2 lambs in adult ewes. Understanding the underlying causes of this low reproductive efficiency and designing methods to improve or mitigate these effects could potentially increase adoption of mating juvenile ewes. In Experiment 1, 2 Cohorts of ewes, born a year apart, were mated in order to lamb at 1 and 2 years of age and the performance of the ewes at each age was compared. Onset of puberty, mating by the fertile ram, ovulation rate, early pregnancy (day 30-35) litter size, number of lambs born and number of lambs weaned were measured. In juvenile ewes, by day 35 of pregnancy, 43% of ova had failed to become a viable embryo and this early loss was the largest contributor to the poor reproductive performance observed. Compared with young adult ewes, ovulation rate was lower (pewes with a greater ovulation rate (pewes, failure to mate with the ram, lower ovulation rate and increased fertilisation failure/embryo loss underlie their poor reproductive performance. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Difficult cases in heart failure: the challenge of neurocognitive dysfunction in severe heart failure.

    Science.gov (United States)

    Sangha, Sumadeep S; Uber, Patricia A; Park, Myung H; Scott, Robert L; Mehra, Mandeep R

    2002-01-01

    Often ignored, neurocognitive dysfunction in chronic heart failure represents a daunting morbidity progressing to loss of self-reliance. Although the precise mechanisms arbitrating the development of this disorder remain elusive, microembolization and cerebral hypoperfusion are implicated. Other causes of cognitive decline may include prior cardiac surgery, chronic hypertension, sleep disordered breathing, hyperhomocysteinemia, dementia of aging, and more traditional causes such as Alzheimer's disease. The discovery of neurocognitive defects in heart failure must prompt a well-constructed diagnostic evaluation to search for the underlying causes since this process may be at least partially reversible in many cases. Copyright 2002 CHF, Inc

  14. Update on Common-Cause Failure Experience and Mitigation Practices

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Richard Thomas [ORNL; Muhlheim, Michael David [ORNL; Pullum, Laura L [ORNL; Smith, Cyrus M [ORNL; Holcomb, David Eugene [ORNL; Korsah, Kofi [ORNL

    2014-04-01

    Experience in other industries has shown that digital technology can provide substantial benefits in terms of performance and reliability. However, the U.S. nuclear power industry has been slow to adopt the technology extensively in its instrumentation and control (I&C) applications because of inhibiting factors such as regulatory uncertainty, insufficient technological experience base, implementation complexity, limited availability of nuclear-qualified products and vendors, and inadequate definition of modernization cost recapture. Although there have been examples of digital technology usage in the nuclear power industry, challenges to the qualification of digital technology for high-integrity nuclear power plant (NPP) applications have severely constrained more widespread progress in achieving the benefits that are possible through the transition to digital. The U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) established the Advanced Sensors and Instrumentation (ASI) technology area under the Nuclear Energy Enabling Technologies (NEET) Program to coordinate the instrumentation and controls (I&C) research across DOE NE and to identify and lead efforts to address common needs. As part of the NEET ASI research program, the Digital Technology Qualification project was established. Under this project, the Oak Ridge National Laboratory (ORNL) is leading the investigation into mitigation of digital common-cause failure (CCF) vulnerabilities for nuclear-qualified applications. This technical report documents updated and expanded findings from research activities by ORNL. Specifically, the report describes CCF experience in the nuclear and nonnuclear industries, identifies the state of the practice for CCF mitigation through key examples, and presents conclusions from the determination of knowledge gaps.

  15. Patterns of severe acute renal failure in a referral center in Sudan: Excluding intensive care and major surgery patients

    International Nuclear Information System (INIS)

    Kaballo, Babikir G.; Khogali, Mohamed S.; Khalifa, Eman H.; Khalil, Eltahir A.G.; El-Hasaan, Ahmad M.; Abu-Aisha, H.

    2007-01-01

    Acute renal failure (ARF) is a common health problem worldwide. There is limited data on the pattern of ARF in Sudan. Moreover, glomerular diseases, which are a well known cause of ARF, have not been accurately and adequately diagnosed previously. A retrospective study on the patterns of ARF was carried out in a general nephrology referral center in Sudan during the period from February 2003 to February 2004.Patients from intensive care units with ARF and those who developed ARF after massive surgery were excluded from the study. Renal biopsy was performed when indicated and studied with light and immunofluorescent microscopy. Eighty-nine patients (57 (64%) cases were males and mean age was 39+-19.4 years) fulfilled the criteria for the diagnosis of advanced renal failure requiring renal function replacement therapy. Acute tubular necrosis (ATN) was diagnosed in 50 (56%) patients; 33 (66%) ATN patients had renal failure as a complication of volume depletion, fulminant infections (particularly malaria and typhoid fever) or snakebites, and 12 (13.4%) patients ingested paraphenylene-diamine (PPD) (hair/Henna dye) in suicidal attempts. Eight (9%) patients of the total study group had glomerural diseases and 11 (12.3%) had obstructive uropathy associated with ARF; cause of ARF could not be determined in 17 (19%) patients. Fifty-three (60%) patients recovered their renal function, six (6.7%) patients progressed to chronic kidney disease (CKD), 16(18%) died and 14(16%) were lost to follow-up. In conclusion, patients with ARF associated with ATN had a favorable prognosis except when ATN was associated PPD poisoning. (author)

  16. Patterns of severe acute renal failure in a referral center in Sudan: Excluding intensive care and major surgery patients

    Energy Technology Data Exchange (ETDEWEB)

    Kaballo, Babikir G; Khogali, Mohamed S [Nephrology Unit, Military Hospital, Omdurman (Sudan); Khalifa, Eman H [Faculty of Medical Laboratory Sciences, Univ. of Khartoum (Sudan); Khalil, Eltahir A.G.; El-Hasaan, Ahmad M [Institute of Endemic Diseases, Univ. of Khartoum (Sudan); Abu-Aisha, H [The National Ribat Univ., Khartoum (Sudan)

    2007-07-01

    Acute renal failure (ARF) is a common health problem worldwide. There is limited data on the pattern of ARF in Sudan. Moreover, glomerular diseases, which are a well known cause of ARF, have not been accurately and adequately diagnosed previously. A retrospective study on the patterns of ARF was carried out in a general nephrology referral center in Sudan during the period from February 2003 to February 2004.Patients from intensive care units with ARF and those who developed ARF after massive surgery were excluded from the study. Renal biopsy was performed when indicated and studied with light and immunofluorescent microscopy. Eighty-nine patients (57 (64%) cases were males and mean age was 39+-19.4 years) fulfilled the criteria for the diagnosis of advanced renal failure requiring renal function replacement therapy. Acute tubular necrosis (ATN) was diagnosed in 50 (56%) patients; 33 (66%) ATN patients had renal failure as a complication of volume depletion, fulminant infections (particularly malaria and typhoid fever) or snakebites, and 12 (13.4%) patients ingested paraphenylene-diamine (PPD) (hair/Henna dye) in suicidal attempts. Eight (9%) patients of the total study group had glomerural diseases and 11 (12.3%) had obstructive uropathy associated with ARF; cause of ARF could not be determined in 17 (19%) patients. Fifty-three (60%) patients recovered their renal function, six (6.7%) patients progressed to chronic kidney disease (CKD), 16(18%) died and 14(16%) were lost to follow-up. In conclusion, patients with ARF associated with ATN had a favorable prognosis except when ATN was associated PPD poisoning. (author)

  17. Interprofessional communication failures in acute care chains: How can we identify the causes?

    Science.gov (United States)

    van Leijen-Zeelenberg, Janneke E; van Raak, Arno J A; Duimel-Peeters, Inge G P; Kroese, Mariëlle E A L; Brink, Peter R G; Vrijhoef, Hubertus J M

    2015-01-01

    Although communication failures between professionals in acute care delivery occur, explanations for these failures remain unclear. We aim to gain a deeper understanding of interprofessional communication failures by assessing two different explanations for them. A multiple case study containing six cases (i.e. acute care chains) was carried out in which semi-structured interviews, physical artifacts and archival records were used for data collection. Data were entered into matrices and the pattern-matching technique was used to examine the two complementary propositions. Based on the level of standardization and integration present in the acute care chains, the six acute care chains could be divided into two categories of care processes, with the care chains equally distributed among the categories. Failures in communication occurred in both groups. Communication routines were embedded within organizations and descriptions of communication routines in the entire acute care chain could not be found. Based on the results, failures in communication could not exclusively be explained by literature on process typology. Literature on organizational routines was useful to explain the occurrence of communication failures in the acute care chains. Organizational routines can be seen as repetitive action patterns and play an important role in organizations, as most processes are carried out by means of routines. The results of this study imply that it is useful to further explore the role of organizational routines on interprofessional communication in acute care chains to develop a solution for failures in handover practices.

  18. Progressive outer retinal necrosis after rituximab and cyclophosphamide therapy.

    Science.gov (United States)

    Dogra, Mohit; Bajgai, Priya; Kumar, Ashok; Sharma, Aman

    2018-04-01

    We report a case of progressive outer retinal necrosis (PORN) in a patient of microscopic polyangitis (MPA), being treated with immunosuppressive drugs such as cyclophosphamide and rituximab. Her aqueous tap was positive for Varicella Zoster virus and she was treated with oral and intravitreal antivirals, along with discontinuation of one of the immunosuppressive agents, i.e. rituximab, which might have led to reactivation of the virus causing necrotizing retinitis lesions. Rituximab and cyclophosphamide are extremely potent drugs, which are necessary to manage immunological disorders such as MPA. However, they may predispose the patient to serious complications like viral infections, including PORN.

  19. Association of the Endobiont Double-Stranded RNA Virus LRV1 With Treatment Failure for Human Leishmaniasis Caused by Leishmania braziliensis in Peru and Bolivia.

    Science.gov (United States)

    Adaui, Vanessa; Lye, Lon-Fye; Akopyants, Natalia S; Zimic, Mirko; Llanos-Cuentas, Alejandro; Garcia, Lineth; Maes, Ilse; De Doncker, Simonne; Dobson, Deborah E; Arevalo, Jorge; Dujardin, Jean-Claude; Beverley, Stephen M

    2016-01-01

    Cutaneous and mucosal leishmaniasis, caused in South America by Leishmania braziliensis, is difficult to cure by chemotherapy (primarily pentavalent antimonials [Sb(V)]). Treatment failure does not correlate well with resistance in vitro, and the factors responsible for treatment failure in patients are not well understood. Many isolates of L. braziliensis (>25%) contain a double-stranded RNA virus named Leishmaniavirus 1 (LRV1), which has also been reported in Leishmania guyanensis, for which an association with increased pathology, metastasis, and parasite replication was found in murine models. Here we probed the relationship of LRV1 to drug treatment success and disease in 97 L. braziliensis-infected patients from Peru and Bolivia. In vitro cultures were established, parasites were typed as L. braziliensis, and the presence of LRV1 was determined by reverse transcription-polymerase chain reaction, followed by sequence analysis. LRV1 was associated significantly with an increased risk of treatment failure (odds ratio, 3.99; P = .04). There was no significant association with intrinsic Sb(V) resistance among parasites, suggesting that treatment failure arises from LRV1-mediated effects on host metabolism and/or parasite survival. The association of LRV1 with clinical drug treatment failure could serve to guide more-effective treatment of tegumentary disease caused by L. braziliensis. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  20. Heart failure and sudden cardiac death in heritable thoracic aortic disease caused by pathogenic variants in the SMAD3 gene.

    Science.gov (United States)

    Backer, Julie De; Braverman, Alan C

    2018-05-01

    Predominant cardiovascular manifestations in the spectrum of Heritable Thoracic Aortic Disease include by default aortic root aneurysms- and dissections, which may be associated with aortic valve disease. Mitral- and tricuspid valve prolapse are other commonly recognized features. Myocardial disease, characterized by heart failure and/or malignant arrhythmias has been reported in humans and in animal models harboring pathogenic variants in the Fibrillin1 gene. Description of clinical history of three cases from one family in Ghent (Belgium) and one family in St. Louis (US). We report on three cases from two families presenting end-stage heart failure (in two) and lethal arrhythmias associated with moderate left ventricular dilatation (in one). All three cases harbor a pathogenic variant in the SMAD3 gene, known to cause aneurysm osteoarthritis syndrome, Loeys-Dietz syndrome type 3 or isolated Heritable Thoracic Aortic Disease. These unusual presentations warrant awareness for myocardial disease in patients harboring pathogenic variants in genes causing Heritable Thoracic Aortic Disease and indicate the need for prospective studies in larger cohorts. © 2018 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.

  1. Clinical outcomes of isolated renal failure compared to other forms of organ failure in patients with severe acute pancreatitis.

    Science.gov (United States)

    Gougol, Amir; Dugum, Mohannad; Dudekula, Anwar; Greer, Phil; Slivka, Adam; Whitcomb, David C; Yadav, Dhiraj; Papachristou, Georgios I

    2017-08-07

    To assess differences in clinical outcomes of isolated renal failure (RF) compared to other forms of organ failure (OF) in patients with severe acute pancreatitis (SAP). Using a prospectively maintained database of patients with acute pancreatitis admitted to a tertiary medical center between 2003 and 2016, those with evidence of persistent OF were classified to renal, respiratory, cardiovascular, or multi-organ (2 or more organs). Data regarding demographics, comorbidities, etiology of acute pancreatitis, and clinical outcomes were prospectively recorded. Differences in clinical outcomes after development of isolated RF in comparison to other forms of OF were determined using independent t and Mann-Whitney U tests for continues variables, and χ 2 test for discrete variables. Among 500 patients with acute pancreatitis, 111 patients developed persistent OF: mean age was 54 years, and 75 (67.6%) were male. Forty-three patients had isolated OF: 17 (15.3%) renal, 25 (21.6%) respiratory, and 1 (0.9%) patient with cardiovascular failure. No differences in demographics, etiology of acute pancreatitis, systemic inflammatory response syndrome scores, or development of pancreatic necrosis were seen between patients with isolated RF vs isolated respiratory failure. Patients with isolated RF were less likely to require nutritional support (76.5% vs 96%, P = 0.001), ICU admission (58.8% vs 100%, P = 0.001), and had shorter mean ICU stay (2.4 d vs 15.7 d, P pancreatitis.

  2. Pentoxifylline Ameliorates Glomerular Basement Membrane Ultrastructural Changes Caused by Gentamicin Administration in Rats

    Directory of Open Access Journals (Sweden)

    Nenad Stojiljković

    2009-08-01

    Full Text Available Gentamicin is commonly used for the treatment of severe gram negative bacterial infections but inevi-tably cause renal failure during prolonged use. The aim of our study was to emphasize protective effects of pentoxifylline on glomerular basement membrane (GBM alterations induced by gentamicin in rats. Experiments were done on 40 male Wistar rats divided in three experimental groups. GM-group was treated daily with gentamicin in dose of 100 mg/kg during 8 days. PTX-group was treated daily with pentoxifylline in dose of 45 mg/kg and the same dose of gentamicin as in GM-group during 8 days. The control group received 1 ml/day saline intraperitoneally. Morphometric parameter measured during the analysis was glomerular basement membrane thickness. In GM-group of animals glomeruli were en-larged and GMB was diffusely and unequally thickened with neutrophil cells infiltration. In proximal tu-bules epithelial cells, vacuolization of cytoplasm with coagulation-type necrosis were observed. In PTX-group of animals glomeruli were somewhat enlarged and GBM was thickened only in some segments. Coagulation-type necrosis was not found. Blood urea and serum creatinine concentration in GM-group were significantly elevated in comparison with PTX-group while potassium level was decreased. Our results suggest that PTX has protective effects on GBM and proximal tubules in GM-treated rats.

  3. Bilateral acute retinal necrosis after herpetic meningitis

    Directory of Open Access Journals (Sweden)

    Katsura T

    2012-04-01

    Full Text Available Keisho Hirota1,2, Masayuki Akimoto1,3, Toshiaki Katsura21Department of Ophthalmology, Kyoto Medical Center, National Hospital Organization, 2Internal Medicine, Kyoto Medical Center, 3Clinical Research Center, Kyoto Medical Center, Kyoto, JapanPurpose: The report of a case of bilateral acute retinal necrosis after herpetic meningitis.Case report: A 47-year-old man was admitted with the chief complaint of persistent high fever and transient loss of consciousness. Although his general condition improved after intravenous acyclovir administration, the patient presented with visual loss in both eyes 4 days after admission. Visual acuity in his right eye was 20/200 and his left eye had light perception alone. Both eyes showed panretinal arteritis diagnosed as acute retinal necrosis. Panretinal photocoagulation was performed for both eyes. Progression of retinal detachment was prevented in both eyes; however, visual acuity of the left eye was totally lost because of neovascular glaucoma. Visual acuity of the right eye recovered to 20/20.Conclusion: Although cases of bilateral acute retinal necrosis have been reported after herpetic encephalitis, this condition is rare after herpetic meningitis. Prophylactic acyclovir therapy and early panretinal photocoagulation may prevent retinal detachment and improve the prognosis. Neurologists and ophthalmologists should be aware that not only herpetic encephalitis but also herpetic meningitis can lead to acute retinal necrosis within a very short interval.Keywords: acute retinal necrosis, herpetic meningitis, herpes simplex, varicella zoster virus

  4. Use if a soecuak sokubt ub reverse syrak artery flap to reduce venous congestion and flap necrosis

    International Nuclear Information System (INIS)

    Masood, T.; Ahmed, R.; Obaidullah, M.

    2016-01-01

    Background: Distally based sural fascio-cutaneous flap is a commonly performed plastic surgery procedure for the coverage of distal third of leg, ankle and foot defects. However congestion is the main complication of this flap which results into partial or complete loss of the flap. We devised a special splint to reduce this complication and retrospectively reviewed its effect on this complication between two groups. Methods: This retrospective study was carried out at Northwest General hospital between 1995 and 2012. Group-A included 30 patients who were managed without the splint between 1995 and 2005 and group B comprised of 35 patients were treated with the splint between 2006 and 2012. Complications like venous congestion, epidermolysis, and partial and complete flap failure were documented. Data were analyzed by SPSS.16.5 software. Chi- square test was used for data analysis. P value less than 0.05 was considered as the level of significance. Results: Total 65 patients were operated. Age of the patients ranged from 7 to 60 years. Road traffic accident and spoke wheel injury was the main cause of soft tissue loss in our patients. In group A 12 patients suffered from venous congestion. Out of 12, three patients had epidermolysis while partial flap necrosis occurred in 9 patients. Only 3 patients had venous congestion in group B. Two patients suffered from epidermolysis and one had partial flap necrosis. None of patient suffered from complete flap loss in both groups. Conclusion: Reverse sural artery flap continues to be a versatile flap for distal lower extremity reconstruction. By using a special splint to reduce pressure on the pedicle site as a modification, flap complication rate can be decreased significantly. (author)

  5. Heart failure - fluids and diuretics

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000112.htm Heart failure - fluids and diuretics To use the sharing features ... to Expect at Home When you have heart failure, your heart does not pump out enough blood. This causes ...

  6. An analytical model for interactive failures

    International Nuclear Information System (INIS)

    Sun Yong; Ma Lin; Mathew, Joseph; Zhang Sheng

    2006-01-01

    In some systems, failures of certain components can interact with each other, and accelerate the failure rates of these components. These failures are defined as interactive failure. Interactive failure is a prevalent cause of failure associated with complex systems, particularly in mechanical systems. The failure risk of an asset will be underestimated if the interactive effect is ignored. When failure risk is assessed, interactive failures of an asset need to be considered. However, the literature is silent on previous research work in this field. This paper introduces the concepts of interactive failure, develops an analytical model to analyse this type of failure quantitatively, and verifies the model using case studies and experiments

  7. [Short-term curative effects of Tantalum rod treatment in early avascular necrosis].

    Science.gov (United States)

    Ye, Fu-Sheng; Ni, Zhe-Ji; Chu, Xiao-Bing; He, Bang-Jian; Li, Ju; Tong, Pei-Jian

    2013-08-01

    To explore the recent clinical curative effect of Tantalum rod in treating the early avascular necrosis. From January 2008 to November 2008, the 25 patients (39 hips) with early avascular necrosis accepted tantalum rod placement and included 9 males (11 hips) and 16 females (28 hips) with an average age of 37 years old ranging from 18 to 74 years old. Four patients (6 hips) caused by Alcoholic, 6 patients (8 hips) by hormone, 2 cases (2 hips) by traumatic, 13 cases (23 hips) by idiopathic. Steinberg preoperative stage involved 7 hips in period I, 24 hips in period II, 8 hips in period III. Curative effect analysis included preoperative and postoperative Harris score, radiographic changes and hip replacement for follow-up to accept the end of the femoral head survival rate. All patients were followed up for 6 to 47 months (averaged 37.4 months). All 12 hips imaging appeard progress,including tantalum rod exit in 1 hip, hip hemiarthroplasty collapse in 3 hips, the area increased to avascular necrosis in 8 hips. Six hips accepted total hip replacement, including imaging progress in 5 hips (41.7%, 5/12), no imaging progress in 1 hip (3.7%,1/27). All hips' Kaplan-Meier survival curves showed 6-month survival rate was (97.4 +/- 2.5)% after tantalum stick insertion, 1-year survival rate was (94.7 +/- 3.6), and 2-year survival rate was (88.6 +/- 5.4)%, 3-year survival rate was (72.5 +/- 11.2). It is effective for treatment of avascular necrosis of femoral head in Steinberg I and II by Tantalum rod, and it can effectively relieve femoral head replacement time.

  8. The methodology of root cause analysis for equipment failure and its application at Guangdong nuclear power stations

    International Nuclear Information System (INIS)

    Gao Ligang; Lu Qunxian

    2004-01-01

    The methodology of Equipment Failure Root Cause Analysis (RCA) is described, as a systematic analysis methodology, it includes 9 steps. Its process is explained by some real examples, and the 6 precautions applying RCA is pointed out. The paper also summarizes the experience of RCA application at Daya Bay Nuclear Power Station, and the 7 key factors for RCA success is emphasized, that mainly concerns organization, objective, analyst, analysis technique, external technical supporting system, corrective actions developing and monitoring system for corrective actions. (authors)

  9. Infection and microleakage the caused of endodontic failure

    Directory of Open Access Journals (Sweden)

    Kurniasri Amas Achiar

    2008-03-01

    Full Text Available The success of endodontic treatment depends on the quality of endodontic treatment and the final restoration. The mean reason for endodontic treatment failure is usually microleakage. That is why it becomes one of the priorities for dental research to prevent microleakage. Infection during the root canal treatment can be prevented. First, by employing strict aseptic clinical techniques follows by cleaning all bacteria and preoperative necrotic pulp-tissue remnants from the root canal. Irrigants are essential in this phase. The shaping of the canal is also an important prerequisite for endodontic success. Removal of the smear layer can enhance seal ability. Second, obturation of the root canal should leave the tooth in the most biological inert condition possible, and it must prevent reinfection as well as the growth of any microorganisms remaining in the canal. The application of an antibacterial dressing between appointments is absolutely necessary or the root canal has to be obturated at the first appointment in order to deprive the microorganisms of nutrients and space to multiply. The temporary filling must be at least 3.5 mm thick. Failure occurs because of missed canals, iatrogenic events and radicular fractures have to be avoided. At the end, clinicians have to confirm that the root canal is cleaned and hermetically obturated because hermetic root canal filling will prevent the leakage of an irritant to the apical area.

  10. Subcutaneous fat necrosis of the newborn.

    Science.gov (United States)

    Oswalt, G C; Montes, L F; Cassady, G

    1978-08-01

    Subcutaneous fat necrosis of the newborn (SFNN) developed in a 1-week-old black boy. His mother had received numerous medications for eclampsia. Birth was by Caesarean section and complicated by meconium aspiration. There were numerous nodules over the back, buttocks and extremities that yielded a caseous-like material. Microscopically, these nodules showed crystallization and necrosis of the fat. Hypoglycemia, pneumonia, oliguria, thrombocytopenia, seizures and urinary infection were associated with the cutaneous problem and led to a fatal outcome 2 weeks after birth.

  11. Bioartificial liver and liver transplantation: new modalities for the treatment of liver failure

    Directory of Open Access Journals (Sweden)

    DING Yitao

    2017-09-01

    Full Text Available The main features of liver failure are extensive necrosis of hepatocytes, rapid disease progression, and poor prognosis, and at present, there are no effective drugs and methods for the treatment of liver failure. This article summarizes four treatment methods for liver failure, i.e., medical treatment, cell transplantation, liver transplantation, and artificial liver support therapy, and elaborates on the existing treatment methods. The current medical treatment regimen should be optimized; cell transplantation has not been used in clinical practice; liver transplantation is the most effective method, but it is limited by donor liver shortage and high costs; artificial liver can effectively remove toxic substances in human body. Therefore, this article puts forward artificial liver as a transition for liver transplantation; artificial liver can buy time for liver regeneration or liver transplantation and prolong patients′ survival time and thus has a promising future. The new treatment modality of bioartificial liver combined with liver transplantation may bring good news to patients with liver failure.

  12. 'Femoral head necrosis' in metabolic and hormonal osteopathies

    International Nuclear Information System (INIS)

    Heuck, F.H.W.; Treugut, H.

    1984-01-01

    The pathogenesis of bone necrosis is discussed with special attention and with respect to metabolic, hormonal, and vascular factors. The influence of statics and dynamics of the hip joint bones for the development of aseptic necrosis are discussed. 45 patients with ''idiopathic femoral head necroses'' were observed, including 6 cases of renal osteopathy following renal transplantation and immune suppression therapy, 14 cases of long term corticoid therapy, and 11 cases of liver diseases of different genesis. The femoral head necrosis understood as complication of an osteopathy. In our patients there were 31 males and 14 females - which means higher involvement of males. Plain radiological findings and CT-findings of changes of the femoral heat structure in different stages of the disease are described. Early diagnosis of metabolic and hormonal osteopathies is demanded for a joint keeping therapy of the beginning femoral head necrosis. (orig.) [de

  13. Patient-related predictors of implant failure after primary total hip replacement in the initial, short- and long-terms

    DEFF Research Database (Denmark)

    Johnsen, S.P.; Sørensen, H.T.; Lucht, Ulf

    2006-01-01

    replacement, an age of 80 years or more and hip replacement undertaken as a sequela of trauma, for avascular necrosis or paediatric conditions, were associated with an increased risk of failure. However, during six months to 8.6 years after surgery, being less than 60 years old was associated...

  14. Heart Failure in the Elderly

    NARCIS (Netherlands)

    B. Cost (Bernard)

    2000-01-01

    textabstractHeart failure is a clinical syndrome with various causes for which no universally accepted definition exists. Packer's definition of heart failure "representing a complex clinical syndrome characterised by abnonnalities of left ventricular function and neurohumoral regulation. which are

  15. CFD research on runaway transient of pumped storage power station caused by pumping power failure

    International Nuclear Information System (INIS)

    Zhang, L G; Zhou, D Q

    2013-01-01

    To study runaway transient of pumped storage power station caused by pumping power failure, three dimensional unsteady numerical simulations were executed on geometrical model of the whole flow system. Through numerical calculation, the changeable flow configuration and variation law of some parameters such as unit rotate speed,flow rate and static pressure of measurement points were obtained and compared with experimental data. Numerical results show that runaway speed agrees well with experimental date and its error was 3.7%. The unit undergoes pump condition, brake condition, turbine condition and runaway condition with flow characteristic changing violently. In runaway condition, static pressure in passage pulses very strongly which frequency is related to runaway speed

  16. Central oxygen pipeline failure

    African Journals Online (AJOL)

    surgical intensive care unit (ICU), with two patients on full ventilation and ... uncertainty around the cause of the failure and the restoration, .... soon as its level also falls below three tons. Should ... (properly checked and closed prior to each anaesthetic). ... in use at the time of the central oxygen pipeline failure at Tygerberg.

  17. Development of delayed radiation necrosis. Case report

    Energy Technology Data Exchange (ETDEWEB)

    Ohara, ShigFeki; Takagi, Terumasa [Meitetsu Hospital, Nagoya (Japan); Shibata, Taichiro; Nagai, Hajime

    1983-04-01

    The authors discussed the developing process of delayed radiation necrosis of the brain from the case of a 42-year-old female who developed intracranial hypertension and left hemiparesis 5 and a half years after radiotherapy for pituitary adenoma. The initial sign of radiation necrosis was from a CT scan taken 3 and a half years after radiotherapy showing an irregular low density lesion in the right temporal lobe. CT scan 2 years later demonstrated displacement of the midline structures to the left and a larger low density lesion with partially high density in the right MCA territory that was enhanced with intravenous contrast medium. Recovery after a right temporal lobectomy and administration of steroid hormone were uneventful. Eight months later there were no signs of raised intracranial pressure nor of neurological deficits. Tissues obtained from the right temporal lobe at lobectomy revealed the characteristic changes of delayed radiation necrosis; a mixture of fresh, recent, and old vascular lesions in the same specimen. From these findings, it was speculated that delayed radiation necrosis might initially occur within several years after radiotherapy and might gradually take a progressive and extended course, even in cases whose clinical symptoms develop much later.

  18. Acute renal failure in Yemeni patients

    Directory of Open Access Journals (Sweden)

    Muhamed Al Rohani

    2011-01-01

    Full Text Available Acute renal failure (ARF is defined as a rapid decrease in the glomerular filtration rate, occurring over a period of hours to days. The Science and Technology University Hospital, Sana′a, is a referral hospital that caters to patients from all parts of Yemen. The aim of this study is to have a deeper overview about the epidemiological status of ARF in Yemeni patients and to identify the major causes of ARF in this country. We studied 203 patients with ARF over a period of 24 months. We found that tropical infectious diseases constituted the major causes of ARF, seen in 45.3% of the patients. Malaria was the most important and dominant infectious disease causing ARF. Hypotension secondary to infection or cardiac failure was seen in 28.6% of the patients. Obstructive nephropathy due to urolithiasis or prostate enlargement was the cause of ARF in a small number of patients. ARF was a part of multi-organ failure in 19.7% of the patients, and was accompanied by a high mortality rate. Majority of the patients were managed conservatively, and only 39.9% required dialysis. Our study suggests that early detection of renal failure helps improve the outcome and return of renal function to normal. Mortality was high in patients with malaria and in those with associated hepatocellular failure.

  19. Development of a heat exchanger root-cause analysis methodology

    International Nuclear Information System (INIS)

    Jarrel, D.B.

    1989-01-01

    The objective of this work is to determine a generic methodology for approaching the accurate identification of the root cause of component failure. Root-cause determinations are an everyday challenge to plant personnel, but they are handled with widely differing degrees of success due to the approaches, levels of diagnostic expertise, and documentation. The criterion for success is simple: If the root cause of the failure has truly been determined and corrected, the same causal failure relationship will not be demonstrated again in the future. The approach to root-cause analysis (RCA) element definition was to first selectively choose and constrain a functionally significant component (in this case a component cooling water to service water heat exchanger) that has demonstrated prevalent failures. Then a root cause of failure analysis was performed by a systems engineer on a large number of actual failure scenarios. The analytical process used by the engineer was documented and evaluated to abstract the logic model used to arrive at the root cause. For the case of the heat exchanger, the actual root-cause diagnostic approach is described. A generic methodology for the solution of the root cause of component failure is demonstrable for this general heat exchanger sample

  20. A Case of Trapezium Avascular Necrosis Treated Conservatively.

    Science.gov (United States)

    Petsatodis, Evangelos; Ditsios, Konstantinos; Konstantinou, Panagiotis; Pinto, Iosafat; Kostretzis, Lazaros; Theodoroudis, Ioannis; Pilavaki, Mayia

    2017-01-01

    Avascular necrosis (AVN) of the bones of the wrist most commonly involves the lunate followed by the proximal pole of the scaphoid and the capitate. Trapezium avascular necrosis is extremely rare with only two cases reported in the literature, both of which were treated surgically. In this article, we report a unique case of trapezium avascular necrosis treated conservatively. A 38-year-old man complaining of a 4-month history of mild pain on the base of his right thumb. MRI scan was performed. The clinical presentation and the imaging findings indicated avascular osteonecrosis of the trapezium. The patient was treated with immobilization of the wrist joint for a period of six weeks. Three months later, the patient was free of symptoms and the MRI scan revealed a normal trapezium. AVN of trapezium is extremely rare. Our case shows that immobilization of an early stage avascular necrosis of the trapezium might be a treatment option.

  1. A Case of Trapezium Avascular Necrosis Treated Conservatively

    Directory of Open Access Journals (Sweden)

    Evangelos Petsatodis

    2017-01-01

    Full Text Available Introduction. Avascular necrosis (AVN of the bones of the wrist most commonly involves the lunate followed by the proximal pole of the scaphoid and the capitate. Trapezium avascular necrosis is extremely rare with only two cases reported in the literature, both of which were treated surgically. In this article, we report a unique case of trapezium avascular necrosis treated conservatively. Case Presentation. A 38-year-old man complaining of a 4-month history of mild pain on the base of his right thumb. MRI scan was performed. The clinical presentation and the imaging findings indicated avascular osteonecrosis of the trapezium. The patient was treated with immobilization of the wrist joint for a period of six weeks. Three months later, the patient was free of symptoms and the MRI scan revealed a normal trapezium. Conclusion. AVN of trapezium is extremely rare. Our case shows that immobilization of an early stage avascular necrosis of the trapezium might be a treatment option.

  2. Common Cause Failure Analysis of Control Rods and Drives in the Swedish and Finnish BWR Plants. Operating Experiences in 1983 - 2003

    Energy Technology Data Exchange (ETDEWEB)

    Mankamo, Tuomas [Avaplan Oy, Espoo (Finland)

    2006-11-15

    The control rod and drives in a Boiling Water Reactor (BWR) constitute a highly redundant system. The reliability of the system is determined by how well the design withstands dependencies, as Common Cause Failures (CCFs). This report upgrades an earlier data collection on CCFs of control rod and drives (SKI Report 1996:77) to more recent years, with the objective to report the data to ICDE project (International Common Cause Failure Data Exchange) and to the safety analysts in the Nordic countries. The operating experiences were analyzed at the BWRs of former Asea-Atom design, comprising 9 units in Sweden and Olkiluoto 1 and 2 in Finland, covering years 1983 - 2003. A new logical scheme was developed to classify interconnected failure modes of the two redundant functions for reactivity shutdown, fast hydraulic insertion and slower screw insertion of control rods. The scheme makes an explicit distinction between the different attributes of the failure event: - affected function - affected movement direction - detectability - criticality, i.e. inoperable control rod function versus only degraded functionality Another novel idea emerged for grouping the events according to generic failure mechanism. The generic classes will help to organize and structure the information efficiently, because in most cases within a class, the failure modes prove to be same, or there are only a few alternatives to chose from. From the set of 72 candidate cases, altogether 27 actual or more significant potential CCFs were screened out. Special emphasis was placed to identify any multiple failure or degradation indicating that adjacent rods would be more vulnerable to failure, because such phenomena are far more critical for reactivity shutdown as compared to failure of randomly placed rods. Only slight tendency of position dependence could be determined. Another positive insight is that the events, where foreign objects caused the jamming of rod insertion, were separated by both

  3. Anesthetic propofol overdose causes endothelial cytotoxicity in vitro and endothelial barrier dysfunction in vivo

    International Nuclear Information System (INIS)

    Lin, Ming-Chung; Chen, Chia-Ling; Yang, Tsan-Tzu; Choi, Pui-Ching; Hsing, Chung-Hsi; Lin, Chiou-Feng

    2012-01-01

    An overdose and a prolonged treatment of propofol may cause cellular cytotoxicity in multiple organs and tissues such as brain, heart, kidney, skeletal muscle, and immune cells; however, the underlying mechanism remains undocumented, particularly in vascular endothelial cells. Our previous studies showed that the activation of glycogen synthase kinase (GSK)-3 is pro-apoptotic in phagocytes during overdose of propofol treatment. Regarding the intravascular administration of propofol, we therefore hypothesized that propofol overdose also induces endothelial cytotoxicity via GSK-3. Propofol overdose (100 μg/ml) inhibited growth in human arterial and microvascular endothelial cells. After treatment, most of the endothelial cells experienced caspase-independent necrosis-like cell death. The activation of cathepsin D following lysosomal membrane permeabilization (LMP) determined necrosis-like cell death. Furthermore, propofol overdose also induced caspase-dependent apoptosis, at least in part. Caspase-3 was activated and acted downstream of mitochondrial transmembrane potential (MTP) loss; however, lysosomal cathepsins were not required for endothelial cell apoptosis. Notably, activation of GSK-3 was essential for propofol overdose-induced mitochondrial damage and apoptosis, but not necrosis-like cell death. Intraperitoneal administration of a propofol overdose in BALB/c mice caused an increase in peritoneal vascular permeability. These results demonstrate the cytotoxic effects of propofol overdose, including cathepsin D-regulated necrosis-like cell death and GSK-3-regulated mitochondrial apoptosis, on endothelial cells in vitro and the endothelial barrier dysfunction by propofol in vivo. Highlights: ► Propofol overdose causes apoptosis and necrosis in endothelial cells. ► Propofol overdose triggers lysosomal dysfunction independent of autophagy. ► Glycogen synthase kinase-3 facilitates propofol overdose-induced apoptosis. ► Propofol overdose causes an increase

  4. Anesthetic propofol overdose causes endothelial cytotoxicity in vitro and endothelial barrier dysfunction in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ming-Chung [Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan (China); Department of Anesthesiology, Chi Mei Medical Center, Liouying, Tainan, Taiwan (China); Chen, Chia-Ling [Center of Infectious Disease and Signaling Research, College of Medicine, National Cheng Kung University, Tainan, Taiwan (China); Yang, Tsan-Tzu; Choi, Pui-Ching [Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan (China); Hsing, Chung-Hsi [Department of Anesthesiology, Chi Mei Medical Center, Tainan, Taiwan (China); Department of Anesthesiology, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); Lin, Chiou-Feng, E-mail: cflin@mail.ncku.edu.tw [Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan (China); Center of Infectious Disease and Signaling Research, College of Medicine, National Cheng Kung University, Tainan, Taiwan (China); Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan (China); Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan (China)

    2012-12-01

    An overdose and a prolonged treatment of propofol may cause cellular cytotoxicity in multiple organs and tissues such as brain, heart, kidney, skeletal muscle, and immune cells; however, the underlying mechanism remains undocumented, particularly in vascular endothelial cells. Our previous studies showed that the activation of glycogen synthase kinase (GSK)-3 is pro-apoptotic in phagocytes during overdose of propofol treatment. Regarding the intravascular administration of propofol, we therefore hypothesized that propofol overdose also induces endothelial cytotoxicity via GSK-3. Propofol overdose (100 μg/ml) inhibited growth in human arterial and microvascular endothelial cells. After treatment, most of the endothelial cells experienced caspase-independent necrosis-like cell death. The activation of cathepsin D following lysosomal membrane permeabilization (LMP) determined necrosis-like cell death. Furthermore, propofol overdose also induced caspase-dependent apoptosis, at least in part. Caspase-3 was activated and acted downstream of mitochondrial transmembrane potential (MTP) loss; however, lysosomal cathepsins were not required for endothelial cell apoptosis. Notably, activation of GSK-3 was essential for propofol overdose-induced mitochondrial damage and apoptosis, but not necrosis-like cell death. Intraperitoneal administration of a propofol overdose in BALB/c mice caused an increase in peritoneal vascular permeability. These results demonstrate the cytotoxic effects of propofol overdose, including cathepsin D-regulated necrosis-like cell death and GSK-3-regulated mitochondrial apoptosis, on endothelial cells in vitro and the endothelial barrier dysfunction by propofol in vivo. Highlights: ► Propofol overdose causes apoptosis and necrosis in endothelial cells. ► Propofol overdose triggers lysosomal dysfunction independent of autophagy. ► Glycogen synthase kinase-3 facilitates propofol overdose-induced apoptosis. ► Propofol overdose causes an increase

  5. Heart Failure Questions to Ask Your Doctor

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Heart Failure Questions to Ask Your Doctor Updated:May 9, ... you? This content was last reviewed May 2017. Heart Failure • Home • About Heart FailureCauses and Risks for ...

  6. Compounds from multilayer plastic bags cause reproductive failures in artificial insemination.

    Science.gov (United States)

    Nerin, C; Ubeda, J L; Alfaro, P; Dahmani, Y; Aznar, M; Canellas, E; Ausejo, R

    2014-05-09

    High levels of reproductive failure were detected in some Spanish sow farms in the Spring of 2010. Regular returns to estrus and variable reductions in litter size were observed. The problem started suddenly and did not appear to be related to the quality of the ejaculates, disease, alterations of body condition or any other apparent reasons. Subsequent studies determined that the problem was the origin of the plastic bags used for semen storage. Chemical analysis of the suspicious bags identified unexpected compounds such as BADGE, a cyclic lactone and an unknown phthalate that leached into the semen at concentrations of 0.2 to 2.5 mg/L. Spermatozoa preserved in these bags passed all of the routine quality control tests, and no differences were observed between storage in the control and suspicious bags (p > 0.05). In vitro fecundation tests and endocrine profiler panel analysis (EPP) did not show any alterations, whereas the in vivo tests confirmed the described failure. This is the first described relationship between reproductive failure and toxic compounds released from plastic bags.

  7. Compounds from multilayer plastic bags cause reproductive failures in artificial insemination

    Science.gov (United States)

    Nerin, C.; Ubeda, J. L.; Alfaro, P.; Dahmani, Y.; Aznar, M.; Canellas, E.; Ausejo, R.

    2014-05-01

    High levels of reproductive failure were detected in some Spanish sow farms in the Spring of 2010. Regular returns to estrus and variable reductions in litter size were observed. The problem started suddenly and did not appear to be related to the quality of the ejaculates, disease, alterations of body condition or any other apparent reasons. Subsequent studies determined that the problem was the origin of the plastic bags used for semen storage. Chemical analysis of the suspicious bags identified unexpected compounds such as BADGE, a cyclic lactone and an unknown phthalate that leached into the semen at concentrations of 0.2 to 2.5 mg/L. Spermatozoa preserved in these bags passed all of the routine quality control tests, and no differences were observed between storage in the control and suspicious bags (p > 0.05). In vitro fecundation tests and endocrine profiler panel analysis (EPP) did not show any alterations, whereas the in vivo tests confirmed the described failure. This is the first described relationship between reproductive failure and toxic compounds released from plastic bags.

  8. Identification of avascular necrosis in the dysplastic proximal femoral epiphysis

    International Nuclear Information System (INIS)

    Mandell, G.A.; Harcke, H.T.; MacKenzie, W.G.; Bassett, G.S.; Scott, C.I. Jr.; Wills, J.S.

    1989-01-01

    Bilateral radiographic irregularities and deformities of the proximal femoral epiphyses are features of both multiple epiphyseal dysplasia and bilateral idiopathic avascular necrosis. In the past these entities have been difficult to differentiate. This report documents radiographically the occurrence of avascular necrosis in 10 patients with multiple epiphyseal dysplasia by recognizing the superimposition of sclerosis and subchondral fissuring on pre-existing symmetrically irregular proximal femoral ossification centers. Scintigraphic (photopenia) or magnetic resonance (loss of signal) criteria of avascular necrosis confirm its added presence and help to establish an imaging scheme to identify avascular necrosis superimposed on multiple epiphyseal dysplasia. (orig.)

  9. Identification of avascular necrosis in the dysplastic proximal femoral epiphysis

    Energy Technology Data Exchange (ETDEWEB)

    Mandell, G A; Harcke, H T [Alfred I. duPont Inst., Wilmington, DE (USA). Dept. of Medical Imaging; MacKenzie, W G; Bassett, G S [Alfred I. duPont Inst., Wilmington, DE (USA). Dept. of Orthopaedics; Scott, Jr, C I [Alfred I. duPont Inst., Wilmington, DE (USA). Dept. of Genetics; Wills, J S [Medical Center of Delaware, Newark, DE (USA). Dept. of Radiology

    1989-07-01

    Bilateral radiographic irregularities and deformities of the proximal femoral epiphyses are features of both multiple epiphyseal dysplasia and bilateral idiopathic avascular necrosis. In the past these entities have been difficult to differentiate. This report documents radiographically the occurrence of avascular necrosis in 10 patients with multiple epiphyseal dysplasia by recognizing the superimposition of sclerosis and subchondral fissuring on pre-existing symmetrically irregular proximal femoral ossification centers. Scintigraphic (photopenia) or magnetic resonance (loss of signal) criteria of avascular necrosis confirm its added presence and help to establish an imaging scheme to identify avascular necrosis superimposed on multiple epiphyseal dysplasia. (orig.).

  10. Experimental models of hepatotoxicity related to acute liver failure

    Energy Technology Data Exchange (ETDEWEB)

    Maes, Michaël [Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels (Belgium); Vinken, Mathieu, E-mail: mvinken@vub.ac.be [Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels (Belgium); Jaeschke, Hartmut [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City (United States)

    2016-01-01

    Acute liver failure can be the consequence of various etiologies, with most cases arising from drug-induced hepatotoxicity in Western countries. Despite advances in this field, the management of acute liver failure continues to be one of the most challenging problems in clinical medicine. The availability of adequate experimental models is of crucial importance to provide a better understanding of this condition and to allow identification of novel drug targets, testing the efficacy of new therapeutic interventions and acting as models for assessing mechanisms of toxicity. Experimental models of hepatotoxicity related to acute liver failure rely on surgical procedures, chemical exposure or viral infection. Each of these models has a number of strengths and weaknesses. This paper specifically reviews commonly used chemical in vivo and in vitro models of hepatotoxicity associated with acute liver failure. - Highlights: • The murine APAP model is very close to what is observed in patients. • The Gal/ET model is useful to study TNFα-mediated apoptotic signaling mechanisms. • Fas receptor activation is an effective model of apoptosis and secondary necrosis. • The ConA model is a relevant model of auto-immune hepatitis and viral hepatitis. • Multiple time point evaluation needed in experimental models of acute liver injury.

  11. Factors Causing Exclusive Breast Feeding Failure in a Pakistani Urban Population

    International Nuclear Information System (INIS)

    Farrukh, H.; Basheer, F.; Jalil, J.

    2013-01-01

    Objective: To determine the factors responsible for termination of exclusive breast feeding in our population. Location and Duration: A cross sectional study was conducted at Combined Military Hospital Quetta, from February 2010 to June 2010. Study design: Cross-sectional study. Sample Size: A total of 620 mothers carrying healthy infants were interviewed.Inclusion Criteria: Mothers who failed to exclusively breast feed their infants within first six months of life and started supplemental feeds. Data Collection Procedure: A semi-structured, preformed questionnaire was filled containing information about mothers age, infant sex and reasons for discontinuation of exclusive breast feeding. Data Analysis: Data was analyzed using SPSS version 18. Results: Mean maternal age was 25.87 years. Early failure was seen in 41.9%$ and late failure in 58.1% infants. Difficulties in initiating and establishing breast feeding (84%), knowledge deficit about breast feeding benefits (78.8%) and milk insufficiency (69.2%) were the main reasons for early failure. Deficient knowledge about exclusive breast feeding which included its WHO definition of six months and its benefits (88.9%) was the most common reason of addition of weaning diets after 4 months of age. Other significant factors found for failure were working mothers (21.3%), premature delivery (13.5%), early second pregnancy (16.1%), and perception of poor weight gain by infant while exclusively breast fed (19.4%). Conclusion: Exclusive breast feeding ensures the best possible health of an infant. Dedicated efforts are required at national level for dissemination and promotion of knowledge about exclusive breast feeding. (author)

  12. Centrifuge model test of rock slope failure caused by seismic excitation. Applicability to the stability evaluation method of safety factors against sliding

    International Nuclear Information System (INIS)

    Ishimaru, Makoto; Kawai, Tadashi

    2010-01-01

    The purposes of this study are to analyze dynamic failure characteristics of slopes in discontinuous rock mass with brittle fracture by centrifuge model tests and to study applicability to the equivalent linear analysis against dynamic sliding failure of rock slopes. We conducted centrifuge model test using a dip slope model with discontinuities imitated by Teflon sheets. The centrifugal acceleration was 30G, and the acceleration amplitudes of input sin waves were increased gradually at every step. The test results were compared with safety factors of the sliding surface based on the equivalent linear analysis. The following results were obtained: (1) The slope model collapsed when it was excited by the sine wave of 350gal, which was converted to real field scale. (2) Artificial discontinuities considerably affected the collapse, and the type of collapse was plane failure. (3) From response displacement records measured at the slope model, the failure around toe of the slope model probably caused the collapse. (4) The evaluation of safety factors against sliding based on the equivalent linear analysis were conservative compared with the experimental results. (author)

  13. Circuit card failures and industry mitigation strategy

    Energy Technology Data Exchange (ETDEWEB)

    Mondal, U. [Candu Owners Group, Toronto, Ontario (Canada)

    2012-07-01

    In recent years the nuclear industry has experienced an increase in circuit card failures due to ageing of components, inadequate Preventive Maintenance (PM), lack of effective circuit card health monitoring, etc. Circuit card failures have caused loss of critical equipment, e.g., electro hydraulic governors, Safety Systems, resulting in loss of function and in some cases loss of generation. INPO completed a root cause analysis of 40 Reactor Trips/Scrams in US reactors and has recommended several actions to mitigate Circuit Card failures. Obsolescence of discrete components has posed many challenges in conducting effective preventative maintenance on circuit cards. In many cases, repairs have resulted in installation of components that compromise performance of the circuit cards. Improper termination and worn edge connectors have caused intermittent contacts contributing to circuit card failures. Traditionally, little attention is paid to relay functions and preventative maintenance of relay. Relays contribute significantly to circuit card failures and have dominated loss of generation across the power industry. The INPO study recommended a number of actions to mitigate circuit card failures, such as; identification of critical components and single point vulnerabilities; strategic preventative maintenance; protection of circuit boards against electrostatic discharge; limiting power cycles; performing an effective burn-in prior to commissioning of the circuit cards; monitoring performance of DC power supplies; limiting cabinet temperatures; managing of component aging/degradation mechanism, etc. A subcommittee has been set up under INPO sponsorship to understand the causes of circuit card failure and to develop an effective mitigation strategy. (author)

  14. Direct therapeutic applications of calcium electroporation to effectively induce tumor necrosis

    DEFF Research Database (Denmark)

    Frandsen, Stine Krog; Gissel, Hanne; Hojman, Pernille

    2012-01-01

    in vivo. Calcium electroporation elicited dramatic antitumor responses in which 89% of treated tumors were eliminated. Histologic analyses indicated complete tumor necrosis. Mechanistically, calcium electroporation caused acute ATP depletion likely due to a combination of increased cellular use of ATP......, decreased production of ATP due to effects on the mitochondria, as well as loss of ATP through the permeabilized cell membrane. Taken together, our findings offer a preclinical proof of concept for the use of electroporation to load cancer cells with calcium as an efficient anticancer treatment...

  15. {sup 99m}Tc-HDP Bone Scan Findings of Acute Rhabdomyolysis of Lumbar Multifidus and Thigh Muscles and Bone Scan and US Signs of Acute Tubular Necrosis in Excessive Rabbit's Leaping: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Bahk, Yong Whee; Kim, Jang Min [Sung Ae Hospital, Seoul (Korea, Republic of)

    2008-06-15

    Marked rhabdomyolysis (RML) complicated by acute tubular necrosis is not a rare disease. It is characterized by disintegration of skeletal muscle fibers due to a variety of causes including excessive physical exercise, trauma, operation, infection, bed-ridden life, alcohol, drugs, toxins, exhaustion and others. We report a case of RML with acute renal failure studied using magnification bone scan which specifically identified the muscles injured by excessive rabbit's leap. The injured muscles recognized were the multifidus of the lumbar spine and the anterior and posterior muscle groups of the thigh. In addition, {sup 99}mTc-HDP bone scan findings of acute tubular necrosis correlated with that of the sonographic signs are described. Patient was treated simply with normal saline hydration and bed rest and uneventfully recovered to be discharged on the fourth hospital day. Lab data on the final hospital day: LDH=20 IU/L (normalized) and CPK=600 IU/L (still higher than normal), BUN=14.2 mg/dl (normalized) and creatinin=1.5 mg/dl (normalized) GOT=20 mg/dl (normalized) and GPT=72 mg/dl (higher than normal), respectively.

  16. Subcutaneous encapsulated fat necrosis

    DEFF Research Database (Denmark)

    Aydin, Dogu; Berg, Jais O

    2016-01-01

    We have described subcutaneous encapsulated fat necrosis, which is benign, usually asymptomatic and underreported. Images have only been published on two earlier occasions, in which the necrotic nodules appear "pearly" than the cloudy yellow surface in present case. The presented image may help...

  17. Avascular necrosis of bone following renal transplantation | Naiker ...

    African Journals Online (AJOL)

    Alcohol conswnption and radiological evidence of osteoporosis were more prevalent in the avascular necrosis group (42,8% v. 29,0% and 28,5% v. 7,2% respectively). Avascular necrosis did not correlate with age, sex, renal function at 1 year or severe secondary hyperparathyroidism. This study suggests that corticosteroid ...

  18. [A right sided colon volvulus with necrosis in a young patient. A case reported].

    Science.gov (United States)

    Márquez-Díaz, Adrián; Ramírez-Ortega, Miguel Angel

    2010-01-01

    Colon volvulus (CV) is the twisting or rotation of an intestinal segment over the mesenterium, which causes occlusion and vascular compromise. It is a frequent disease in individuals over 65 years-old. We report a young patient with right CV and necrosis. A 17 year-old male with clinical findings of acute abdomen presented in the emergency room. During the surgical procedure, a right sided was found, CV with ileocecal valve and caecum ischemia and right colon necrosis with mesenteric vessels thrombosis. The case presented begun with sudden abdominal pain, with intestinal occlusion data, and widespread peritoneal rebound tenderles which suggested an intestinal occlusion. A simple abdomen Rx showed prominent right side colon distention with air levels in small bowel and a "coffee bean" image, suggestive of CVA hemicolectomy with termino-lateral ileocolic anastomosis was performed. Right-sided CV is considered as congenital in origin. They corresponded to 21% of cases in Mexico, with an average age of presentation at 62 years. The CV represents 10% of the causes of large bowel obstruction in Mexico. This is the first case in young people reported in Mexican literature.

  19. Epidemiological characteristics of infectious hematopoietic necrosis virus (IHNV): a review.

    Science.gov (United States)

    Dixon, Peter; Paley, Richard; Alegria-Moran, Raul; Oidtmann, Birgit

    2016-06-10

    Infectious hematopoietic necrosis virus (IHNV, Rhabdoviridae), is the causative agent of infectious hematopoietic necrosis (IHN), a disease notifiable to the World Organisation for Animal Health, and various countries and trading areas (including the European Union). IHNV is an economically important pathogen causing clinical disease and mortalities in a wide variety of salmonid species, including the main salmonid species produced in aquaculture, Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss). We reviewed the scientific literature on IHNV on a range of topics, including geographic distribution; host range; conditions required for infection and clinical disease; minimum infectious dose; subclinical infection; shedding of virus by infected fish; transmission via eggs; diagnostic tests; pathogen load and survival of IHNV in host tissues. This information is required for a range of purposes including import risk assessments; parameterisation of disease models; for surveillance planning; and evaluation of the chances of eradication of the pathogen to name just a few. The review focuses on issues that are of relevance for the European context, but many of the data summarised have relevance to IHN globally. Examples for application of the information is presented and data gaps highlighted.

  20. Progressive outer retinal necrosis after rituximab and cyclophosphamide therapy

    Directory of Open Access Journals (Sweden)

    Mohit Dogra

    2018-01-01

    Full Text Available We report a case of progressive outer retinal necrosis (PORN in a patient of microscopic polyangitis (MPA, being treated with immunosuppressive drugs such as cyclophosphamide and rituximab. Her aqueous tap was positive for Varicella Zoster virus and she was treated with oral and intravitreal antivirals, along with discontinuation of one of the immunosuppressive agents, i.e. rituximab, which might have led to reactivation of the virus causing necrotizing retinitis lesions. Rituximab and cyclophosphamide are extremely potent drugs, which are necessary to manage immunological disorders such as MPA. However, they may predispose the patient to serious complications like viral infections, including PORN.

  1. Necrosis, a regulated mechanism of cell death La necrosis, un mecanismo regulado de muerte celular

    Directory of Open Access Journals (Sweden)

    Mauricio Rojas López

    2010-05-01

    Full Text Available

    Three types of cellular death have been defined by morphological and biochemical criteria: apoptosis, necrosis and autophagy. Apoptosis is a regulated cell death, mainly mediated by caspases; autophagy induces degradation of intracellular damaged organelles through the formation of vesicles that fuse with hydrolytic vacuoles.

     

    Necrosis has been traditionally defined by the rupture the cytoplasmic membrane with subsequent release of intracellular material, triggering localized inflammatory Intrinsic cellular activities and the events preceding cellular collapse are critical to determine the type of tissue damage.

     

    The fact that all three types of cellular death can coexist in any organ and tissue with different availabilities of ATP, suggests that necrosis can be conceived as an active event and that to some extent it may be regulated. Alterations in the structure of proteins and in the

  2. Magnetic Resonance Imaging of Therapy-Induced Necrosis Using Gadolinium-Chelated Polyglutamic Acids

    International Nuclear Information System (INIS)

    Jackson, Edward F.; Esparza-Coss, Emilio; Wen Xiaoxia; Ng, Chaan S.; Daniel, Sherita L.; Price, Roger E.; Rivera, Belinda; Charnsangavej, Chusilp; Gelovani, Juri G.; Li Chun

    2007-01-01

    Purpose: Necrosis is the most common morphologic alteration found in tumors and surrounding normal tissues after radiation therapy or chemotherapy. Accurate measurement of necrosis may provide an early indication of treatment efficacy or associated toxicity. The purpose of this report is to evaluate the selective accumulation of polymeric paramagnetic magnetic resonance (MR) contrast agents-gadolinium p-aminobenzyl-diethylenetriaminepentaacetic acid-poly(glutamic acid) (L-PG-DTPA-Gd and D-PG-DTPA-Gd)-in necrotic tissue. Methods and Materials: Two different solid tumor models, human Colo-205 xenograft and syngeneic murine OCA-1 ovarian tumors, were used in this study. Necrotic response was induced by treatment with poly(L-glutamic acid)-paclitaxel conjugate (PG-TXL). T 1 -weighted spin-echo images were obtained immediately and up to 4 days after contrast injection and compared with corresponding histologic specimens. Two low-molecular-weight contrast agents, DTPA-Gd and oligomeric(L-glutamic acid)-DTPA-Gd, were used as nonspecific controls. Results: Initially, there was minimal tumor enhancement after injection of either L-PG-DTPA-Gd or D-PG-DTPA-Gd, but rapid enhancement after injection of low-molecular-weight agents. However, polymeric contrast agents, but not low-molecular-weight contrast agents, caused sustained enhancement in regions of tumor necrosis in both tumors treated with PG-TXL and untreated tumors. These data indicate that high molecular weight, rather than in vivo biodegradation, is necessary for the specific localization of polymeric MR contrast agents to necrotic tissue. Moreover, biotinylated L-PG-DTPA-Gd colocalized with macrophages in the tumor necrotic areas, suggesting that selective accumulation of L- and D-PG-DTPA-Gd in necrotic tissue was mediated through residing macrophages. Conclusions: Our data suggest that MR imaging with PG-DTPA-Gd may be a useful technique for noninvasive characterization of treatment-induced necrosis

  3. Forensic study into the causes of premature failures in asphalt pavements in Tanzania

    CSIR Research Space (South Africa)

    Anochie-Boateng, Joseph

    2015-11-01

    Full Text Available Tanzania is faced with challenges of premature failures in roads and highways. Some asphalt pavements fail prematurely in less than five years of their expected 20 years design life cycle. These failures have been identified as mostly permanent...

  4. A rare case of avascular necrosis in sickle cell trait: a case report.

    Science.gov (United States)

    Sanders, William J

    2018-01-01

    Sickle cell trait is usually an asymptomatic presentation of a patient with slightly different hemoglobin molecule makeup than normal. It is similar to a more serious disease, sickle cell disease, in which a person's hemoglobin is mutated in such a way that causes their red blood cells to easily change shape in certain environmental and internal states; this causes red blood cells to adhere to the walls and occlude the lumen of the arteries in which they travel, leading to downstream effects secondary to ischemia. Sickle cell trait does not have these ischemic effects, usually. In this case, a young African American female patient presents to the clinic with severe right hip pain. Her past medical history includes sickle cell trait and asthma. She has not been symptomatic of her asthma for years and is not on therapy for it. The pain has lasted for several months and has not improved with anti-inflammatory medication. There is severe pain with internal and external rotation of the hip. The neurovascularity of the lower extremities is intact bilaterally. MRI of the femur shows stage 2 or 3 avascular necrosis of the femoral head, while X-rays of the femur are unremarkable. Non weight-bearing for several weeks was unsuccessful; shortly thereafter, the patient underwent core decompression of the right femoral head as well as starting bisphosphonates. The patient improved temporarily but regressed shortly thereafter. Her avascular necrosis worsened radiographically over the next several months. At this point, the only other option would be to do a total hip arthroplasty, but the patient may need several more throughout her lifetime due to the lifespan of the artificial replacement. There have only been scarce reports of avascular necrosis in patients with sickle cell trait. This manuscript presents such a case and includes the trials and tribulations associated with its management.

  5. [Acute unclassified leukemia with bone marrow necrosis].

    Science.gov (United States)

    Uoshima, N; Yamazaki, N; Iinuma, S; Kimura, S; Wada, K; Kobayashi, Y; Ozawa, M; Horiuchi, H; Maruo, N; Kondo, M

    1991-01-01

    Massive bone marrow necrosis was seen in a 42-year-old male with acute leukemia. In December, 1988, on admission, laboratory data revealed pancytopenia and a high level of serum LDH and ALKP. Bone marrow aspiration resulted in dry-tap and showed bone marrow necrosis in the bone marrow biopsy specimen. A bone marrow scintigraphy with 111In faintly visualized the bone marrow but visualized area was expanded in the extremities compared with normal subjects. The second bone marrow biopsy showed proliferation of blasts. In the middle of March, blasts began to appear in peripheral blood. The blasts were cytochemically negative for POX, Es, PAS, AcP, TdT and had surface markers CD3-, CD19-, CD33-, CD13-, LCA-, HLA-DR-. Even by investigation on rearrangement of the immunoglobulin heavy chain region, an origin of the blasts could not be determined. In April, the number of blasts in peripheral blood increased and hepatosplenomegaly developed rapidly. Therefore, he was put on the chemotherapy with vincristine and prednisolone, but he died of cerebral hemorrhage. The autopsy revealed widespread bone marrow necrosis. It has rarely been reported that massive bone marrow necrosis is found prior to the occurrence of acute unclassified leukemia.

  6. Neurological Respiratory Failure

    Directory of Open Access Journals (Sweden)

    Mohan Rudrappa

    2018-01-01

    Full Text Available West Nile virus infection in humans is mostly asymptomatic. Less than 1% of neuro-invasive cases show a fatality rate of around 10%. Acute flaccid paralysis of respiratory muscles leading to respiratory failure is the most common cause of death. Although the peripheral nervous system can be involved, isolated phrenic nerve palsy leading to respiratory failure is rare and described in only two cases in the English literature. We present another case of neurological respiratory failure due to West Nile virus-induced phrenic nerve palsy. Our case reiterates the rare, but lethal, consequences of West Nile virus infection, and the increase of its awareness among physicians.

  7. Avascular necrosis of the trapezoid bone following carpometacarpal arthroplasty.

    Science.gov (United States)

    Kane, Patrick; Waryasz, Greg; Katarincic, Julie

    2014-03-03

    A 58-year-old female developed avascular necrosis of her trapezoid approximately 3 months after undergoing carpometacarpal arthroplasty. The patient was treated conservatively with immobilization and had complete resolution of her clinical symptoms during her year of follow-up. Additionally, radiographic examination showed complete restoration of the height of her trapezoid approximately 1 year after the index procedure. Avascular necrosis of the trapezoid is extremely rare with very few cases described in the literature. This is the first description of avascular necrosis following carpometacarpal arthroplasty.

  8. The inflammatory biomarker YKL-40 as a new prognostic marker for all-cause mortality in patients with heart failure

    DEFF Research Database (Denmark)

    Harutyunyan, Marina; Christiansen, Michael; Johansen, Julia S

    2011-01-01

    peptide (NT-proBNP) could be a new prognostic biomarker for all-cause mortality in patients with HF. METHODS AND RESULTS: A total of 717 of the 1000 patients with severe left ventricular systolic dysfunction included in the EchoCardiography and Heart Outcome Study were included in Denmark and had blood...... YKL-40 II to IV quartiles, respectively following multivariable adjustment for cardiovascular risk factors (age, left ventricular ejection fraction, gender, history of heart failure, ischemic heart disease, chronic pulmonary disease, diabetes mellitus, stroke, hypertension, NT-proBNP, hs......-CRP, and renal function). CONCLUSION: Serum YKL-40 is significantly associated with all-cause mortality in patients with HF and could potentially be a new prognostic biomarker in these patients....

  9. Recurrent implantation failure: definition and management.

    Science.gov (United States)

    Coughlan, C; Ledger, W; Wang, Q; Liu, Fenghua; Demirol, Aygul; Gurgan, Timur; Cutting, R; Ong, K; Sallam, H; Li, T C

    2014-01-01

    Recurrent implantation failure refers to failure to achieve a clinical pregnancy after transfer of at least four good-quality embryos in a minimum of three fresh or frozen cycles in a woman under the age of 40 years. The failure to implant may be a consequence of embryo or uterine factors. Thorough investigations should be carried out to ascertain whether there is any underlying cause of the condition. Ovarian function should be assessed by measurement of antral follicle count, FSH and anti-Mu¨llerian hormone. Increased sperm DNA fragmentation may be a contributory cause. Various uterine pathology including fibroids, endometrial polyps, congenital anomalies and intrauterine adhesions should be excluded by ultrasonography and hysteroscopy. Hydrosalpinges are a recognized cause of implantation failure and should be excluded by hysterosalpingogram; if necessary, laparoscopy should be performed to confirm or refute the diagnosis. Treatment offered should be evidence based, aimed at improving embryo quality or endometrial receptivity. Gamete donation or surrogacy may be necessary if there is no realistic chance of success with further IVF attempts. Copyright © 2013. Published by Elsevier Ltd.

  10. Effect of pimobendan or benazepril hydrochloride on survival times in dogs with congestive heart failure caused by naturally occurring myxomatous mitral valve disease: the QUEST study.

    Science.gov (United States)

    Häggström, J; Boswood, A; O'Grady, M; Jöns, O; Smith, S; Swift, S; Borgarelli, M; Gavaghan, B; Kresken, J-G; Patteson, M; Ablad, B; Bussadori, C M; Glaus, T; Kovacević, A; Rapp, M; Santilli, R A; Tidholm, A; Eriksson, A; Belanger, M C; Deinert, M; Little, C J L; Kvart, C; French, A; Rønn-Landbo, M; Wess, G; Eggertsdottir, A V; O'Sullivan, M L; Schneider, M; Lombard, C W; Dukes-McEwan, J; Willis, R; Louvet, A; DiFruscia, R

    2008-01-01

    Myxomatous mitral valve disease (MMVD) continues to be an important cause of morbidity and mortality in geriatric dogs despite conventional therapy. Pimobendan in addition to conventional therapy will extend time to sudden cardiac death, euthanasia for cardiac reasons, or treatment failure when compared with conventional therapy plus benazepril in dogs with congestive heart failure (CHF) attributable to MMVD. Two hundred and sixty client-owned dogs in CHF caused by MMVD were recruited from 28 centers in Europe, Canada, and Australia. A prospective single-blinded study with dogs randomized to PO receive pimobendan (0.4-0.6 mg/kg/d) or benazepril hydrochloride (0.25-1.0 mg/kg/d). The primary endpoint was a composite of cardiac death, euthanized for heart failure, or treatment failure. Eight dogs were excluded from analysis. One hundred and twenty-four dogs were randomized to pimobendan and 128 to benazepril. One hundred and ninety dogs reached the primary endpoint; the median time was 188 days (267 days for pimobendan, 140 days for benazepril hazard ratio = 0.688, 95% confidence limits [CL]=0.516-0.916, P= .0099). The benefit of pimobendan persisted after adjusting for all baseline variables. A longer time to reach the endpoint was also associated with being a Cavalier King Charles Spaniel, requiring a lower furosemide dose, and having a higher creatinine concentration. Increases in several indicators of cardiac enlargement (left atrial to aortic root ratio, vertebral heart scale, and percentage increase in left ventricular internal diameter in systole) were associated with a shorter time to endpoint, as was a worse tolerance for exercise. Pimobendan plus conventional therapy prolongs time to sudden death, euthanasia for cardiac reasons, or treatment failure in dogs with CHF caused by MMVD compared with benazepril plus conventional therapy.

  11. Complete Atrioventricular Block Complicating Mitral Infective Endocarditis Caused by Streptococcus Agalactiae.

    Science.gov (United States)

    Arai, Masaru; Nagashima, Koichi; Kato, Mahoto; Akutsu, Naotaka; Hayase, Misa; Ogura, Kanako; Iwasawa, Yukino; Aizawa, Yoshihiro; Saito, Yuki; Okumura, Yasuo; Nishimaki, Haruna; Masuda, Shinobu; Hirayama, Astushi

    2016-09-08

    BACKGROUND Infective endocarditis (IE) involving the mitral valve can but rarely lead to complete atrioventricular block (CAVB). CASE REPORT A 74-year-old man with a history of infective endocarditis caused by Streptococcus gordonii (S. gordonii) presented to our emergency room with fever and loss of appetite, which had lasted for 5 days. On admission, results of serologic tests pointed to severe infection. Electrocardiography showed normal sinus rhythm with first-degree atrioventricular block and incomplete right bundle branch block, and transthoracic echocardiography and transesophageal echocardiography revealed severe mitral regurgitation caused by posterior leaflet perforation and 2 vegetations (5 mm and 6 mm) on the tricuspid valve. The patient was initially treated with ceftriaxone and gentamycin because blood and cutaneous ulcer cultures yielded S. agalactiae. On hospital day 2, however, sudden CAVB requiring transvenous pacing occurred, and the patient's heart failure and infection worsened. Although an emergent surgery is strongly recommended, even in patients with uncontrolled heart failure or infection, surgery was not performed because of the Child-Pugh class B liver cirrhosis. Despite intensive therapy, the patient's condition further deteriorated, and he died on hospital day 16. On postmortem examination, a 2×1-cm vegetation was seen on the perforated posterior mitral leaflet, and the infection had extended to the interventricular septum. Histologic examination revealed extensive necrosis of the AV node. CONCLUSIONS This rare case of CAVB resulting from S. agalactiae IE points to the fact that in monitoring patients with IE involving the mitral valve, clinicians should be aware of the potential for perivalvular extension of the infection, which can lead to fatal heart block.

  12. Avascular Necrosis of Bone after Renal Transplantation - Prevalence and Usefulness of Bone SPECT -

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Yun Young; Yang, Seoung Oh; Ryuu, Jin Sook; Moon, Dae Hyuk; Lee, Hee Kyung [Asan Medical Center, University of Ulsan, Seoul (Korea, Republic of)

    1995-09-15

    Avascular necrosis(AVN) of bone can be resulted from various causes that disturb vascular supply to bone tissue, including steroid therapy after renal transplantation. In this study, we determine the prevalence of the avascular necrosis of bone after renal transplantation and compare the role of the bone scan, SPECT and MRI. In 301 patients with transplanted kidney, the prevalence of avascular necrosis was determined clinically. Site of bone necrosis was evaluated by clinical symptom, bone scan, SPECT and MRI. Bone scan was done in all patients with AVN. Bone SPECT and MRI were done in six cases; and MRI was done in two cases. The prevalence of AVN was 3.3% (10/301), and the site of AVN was 16 femoral heads in 10 patients (bilateral: 60%) and bilateral calcaneal tuberosity in one patient. Bone scan showed typical AVN (cold area with surrounding hot uptake) in 13 lesions, only hot uptake in three lesions (including two calcaneal tuberosities), decreased uptake in one lesion, and normal in one lesion. Decreased uptake and normal lesion showed an equivocal cold area without surrounding hot uptake on SPECT. A symptomatic patient with positive bone SPECT showed normal finding on MRI. The prevalence of AVN of bone after renal transplantation was 3.3%, and whole body bone scan showed multiple bone involvement. Two symptomatic hip joints without definite lesion on whole body bone scan or MRI showed cold defect on SPECT. Therefore, we conclude that bone SPECT should be performed in a symptomatic patient with negative bone scan or MRI in case with high risk of AVN after renal transplantation.

  13. Avascular Necrosis of Bone after Renal Transplantation - Prevalence and Usefulness of Bone SPECT -

    International Nuclear Information System (INIS)

    Choi, Yun Young; Yang, Seoung Oh; Ryuu, Jin Sook; Moon, Dae Hyuk; Lee, Hee Kyung

    1995-01-01

    Avascular necrosis(AVN) of bone can be resulted from various causes that disturb vascular supply to bone tissue, including steroid therapy after renal transplantation. In this study, we determine the prevalence of the avascular necrosis of bone after renal transplantation and compare the role of the bone scan, SPECT and MRI. In 301 patients with transplanted kidney, the prevalence of avascular necrosis was determined clinically. Site of bone necrosis was evaluated by clinical symptom, bone scan, SPECT and MRI. Bone scan was done in all patients with AVN. Bone SPECT and MRI were done in six cases; and MRI was done in two cases. The prevalence of AVN was 3.3% (10/301), and the site of AVN was 16 femoral heads in 10 patients (bilateral: 60%) and bilateral calcaneal tuberosity in one patient. Bone scan showed typical AVN (cold area with surrounding hot uptake) in 13 lesions, only hot uptake in three lesions (including two calcaneal tuberosities), decreased uptake in one lesion, and normal in one lesion. Decreased uptake and normal lesion showed an equivocal cold area without surrounding hot uptake on SPECT. A symptomatic patient with positive bone SPECT showed normal finding on MRI. The prevalence of AVN of bone after renal transplantation was 3.3%, and whole body bone scan showed multiple bone involvement. Two symptomatic hip joints without definite lesion on whole body bone scan or MRI showed cold defect on SPECT. Therefore, we conclude that bone SPECT should be performed in a symptomatic patient with negative bone scan or MRI in case with high risk of AVN after renal transplantation.

  14. Supraspinatus Intramuscular Calcified Hematoma or Necrosis Associated with Tendon Tear

    Directory of Open Access Journals (Sweden)

    Alexandre Lädermann

    2015-01-01

    Full Text Available Introduction. Rotator cuff intramuscular calcification is a rare condition usually caused by heterotopic ossification and myositis ossificans. Case Presentation. We describe a patient with voluminous calcified mass entrapped in supraspinatus muscle associated with corresponding tendon tear. Histological examination corresponded to a calcified hematoma or necrosis. Patient was surgically managed with open excision of the calcified hematoma and rotator cuff arthroscopic repair. At 6 months, supraspinatus muscle was healed, and functional outcome was good. Discussion and Conclusion. We hypothesized that supraspinatus intramuscular calcified hematoma was responsible for mechanical stress on the tendon. This association has never been described.

  15. Imaging of cavitary necrosis in complicated childhood pneumonia

    International Nuclear Information System (INIS)

    Hodina, M.; Schnyder, P.; Gudinchet, F.; Hanquinet, S.; Cotting, J.

    2002-01-01

    The aim of this study was to illustrate the chest radiographs (CR) and CT imaging features and sequential findings of cavitary necrosis in complicated childhood pneumonia. Among 30 children admitted in the Pediatric Intensive Care Unit for persistent or progressive pneumonia, respiratory distress or sepsis despite adequate antibiotic therapy, a study group of 9 children (5 girls and 4 boys; mean age 4 years) who had the radiographic features and CT criteria for cavitary necrosis complicated pneumonia was identified. The pathogens identified were Streptococcus pneumoniae (n=4), Aspergillus (n=2), Legionella (n=1), and Staphylococcus aureus (n=1). Sequential CR and CT scans were retrospectively reviewed. Follow-up CR and CT were evaluated for persistent abnormalities. Chest radiographs showed consolidations in 8 of the 9 patients. On CT examination, cavitary necrosis was localized to 1 lobe in 2 patients and 7 patients showed multilobar or bilateral areas of cavitary necrosis. In 3 patients of 9, the cavitary necrosis was initially shown on CT and visualization by CR was delayed by a time span varying from 5 to 9 days. In all patients with cavities, a mean number of five cavities were seen on antero-posterior CR, contrasting with the multiple cavities seen on CT. Parapneumonic effusions were shown by CR in 3 patients and in 5 patients by CT. Bronchopleural fistulae were demonstrated by CT alone (n=3). No purulent pericarditis was demonstrated. The CT scan displayed persistent residual pneumatoceles of the left lower lobe in 2 patients. Computed tomography is able to define a more specific pattern of abnormalities than conventional CR in children with necrotizing pneumonia and allows an earlier diagnosis of this rapidly progressing condition. Lung necrosis and cavitation may also be associated with Aspergillus or Legionella pneumonia in the pediatric population. (orig.)

  16. Fatal Acute Liver Failure as a Consequence of Regorafenib Treatment in a Metastatic Colon Cancer

    Directory of Open Access Journals (Sweden)

    Dominique Béchade

    2017-08-01

    Full Text Available Regorafenib is a multikinase inhibitor which showed benefits in pretreated metastatic colorectal cancer patients. Hepatotoxicity has been described as a frequent side effect. We report the case of a 65-year-old patient presenting with jaundice, fever, and hepatocellular insufficiency which led to death of the patient. She had previously been treated with several lines of chemotherapy for sub- and diaphragmatic ganglionic metastases of a colon adenocarcinoma. There were no liver metastases. The fatal liver failure occurred at the beginning of treatment with regorafenib at a dosage of 3 tablets per day. No concomitant treatment was given, and other causes of liver damage were eliminated. The liver biopsy showed hepatocyte necrosis with lymphocyte infiltration. This observation illustrates the risk of severe hepatic involvement typically occurring within the first 2 months of treatment. Monitoring liver biology every 2 weeks is essential during the first 2 months to detect any hepatotoxicity.

  17. A Development of Common Cause Failure Propagation Paths Identification Method Using Coloured Petri Nets

    International Nuclear Information System (INIS)

    Yim, Ho Bin; Park, Jae Min; Lee, Chang Gyun; Huh, Jae Young; Lee, Gyu Cheon

    2017-01-01

    The concept of Common-Cause Failure (CCF) first appeared in the aerospace industry several decades ago, and nuclear power industry actively adopted the concept to the nuclear power plant (NPP) system analysis after the TMI accident. Since digital Instrumentation and Control (I and C) systems were applied to the NPP design, the CCF issues once again drew attention from the nuclear power industry in 90's. Identification of CCF has not been considered as a challenging issue because of its simplicity. However, as the systems become more complex and interconnected, demands are increasing to analyze CCF in more detail, for example, CCF with multiple initiating events or supporting situation awareness of the operation crew. The newly suggested CCF propagation paths identification method, CCF-SIREn, is expected to resolve path identification issue more practically and efficiently. CCF-SIREn uses general diagrams so that the compatibility and usability can be hugely increased. It also offers up-to-date CCF information with a least analysis effort whenever the ordinary NPP design change processes are made. A back-propagation technique is still under development to find out root-causes from the suspiciously responding signals, alarms and components. The probabilistic approach is also under consideration to prioritize defined CCF.

  18. Management of infected pancreatic necrosis: state of the art

    Directory of Open Access Journals (Sweden)

    Roberto Rasslan

    Full Text Available ABSTRACT Pancreatic necrosis occurs in 15% of acute pancreatitis. The presence of infection is the most important factor in the evolution of pancreatitis. The diagnosis of infection is still challenging. Mortality in infected necrosis is 20%; in the presence of organic dysfunction, mortality reaches 60%. In the last three decades, there has been a real revolution in the treatment of infected pancreatic necrosis. However, the challenges persist and there are many unsolved questions: antibiotic treatment alone, tomography-guided percutaneous drainage, endoscopic drainage, video-assisted extraperitoneal debridement, extraperitoneal access, open necrosectomy? A step up approach has been proposed, beginning with less invasive procedures and reserving the operative intervention for patients in which the previous procedure did not solve the problem definitively. Indication and timing of the intervention should be determined by the clinical course. Ideally, the intervention should be done only after the fourth week of evolution, when it is observed a better delimitation of necrosis. Treatment should be individualized. There is no procedure that should be the first and best option for all patients. The objective of this work is to critically review the current state of the art of the treatment of infected pancreatic necrosis.

  19. Failure analysis on a ruptured petrochemical pipe

    Energy Technology Data Exchange (ETDEWEB)

    Harun, Mohd [Industrial Technology Division, Malaysian Nuclear Agency, Ministry of Science, Technology and Innovation Malaysia, Bangi, Kajang, Selangor (Malaysia); Shamsudin, Shaiful Rizam; Kamardin, A. [Univ. Malaysia Perlis, Jejawi, Arau (Malaysia). School of Materials Engineering

    2010-08-15

    The failure took place on a welded elbow pipe which exhibited a catastrophic transverse rupture. The failure was located on the welding HAZ region, parallel to the welding path. Branching cracks were detected at the edge of the rupture area. Deposits of corrosion products were also spotted. The optical microscope analysis showed the presence of transgranular failures which were related to the stress corrosion cracking (SCC) and were predominantly caused by the welding residual stress. The significant difference in hardness between the welded area and the pipe confirmed the findings. Moreover, the failure was also caused by the low Mo content in the stainless steel pipe which was detected by means of spark emission spectrometer. (orig.)

  20. Pulmonary hydatid cyst in a pregnant patient causing acute respiratory failure

    Directory of Open Access Journals (Sweden)

    Hijazi Mohammed

    2007-01-01

    Full Text Available A 21-year-old primigravida, at 32 weeks of gestation, presented with acute onset of respiratory failure and circulatory shock. Chest imaging showed findings suggestive of ruptured hydatid cyst, which was confirmed by histology post-thoracotomy. Tissue cultures from the removed cyst grew Mycobacterium tuberculosis also. She was successfully managed in the intensive care unit and was then discharged home on antituberculosis medications in addition to albendazole after prolonged hospitalization and a need for chest tube for bronchopleural fistula. Acute respiratory failure and anaphylactic shock secondary to ruptured pulmonary hydatid cyst and superimposed pulmonary tuberculosis in a pregnant lady should be considered in patients living in endemic areas.

  1. MR imaging of avascular necrosis of carpal bones

    International Nuclear Information System (INIS)

    Taniguchi, Yasunori; Funaoka, Nobuhiko; Yoshida, Munehito; Iwahashi, Toshiyuki; Egawa, Hiromitsu; Shima, Kimihiro; Tamaoki, Tetsuya.

    1991-01-01

    The usefulness of MRI in carpal avascular necrosis was investigated in 20 cases, 16 in lunates, 3 in scaphoids and 1 in triquetrum, with T1 and T2 weighted images of the spin echo and T2 weighted images of the field echo. Early diagnosis of carpal bone necrosis was possible when the T1 weighted image showed a moderate low intensity signal. A high intensity signal in the T2 weighted image indicated the onset of revascularization, and a favorable prognosis. A normal signal indicated healing of carpal avascular necrosis. MRI was found to be very useful in establishing the diagnosis and in determining the prognosis of carpal osteonecrosis. (author)

  2. MR imaging of avascular necrosis of carpal bones

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Yasunori; Funaoka, Nobuhiko; Yoshida, Munehito [Kinan General Hospital, Wakayama (Japan); Iwahashi, Toshiyuki; Egawa, Hiromitsu; Shima, Kimihiro; Tamaoki, Tetsuya

    1991-03-01

    The usefulness of MRI in carpal avascular necrosis was investigated in 20 cases, 16 in lunates, 3 in scaphoids and 1 in triquetrum, with T1 and T2 weighted images of the spin echo and T2 weighted images of the field echo. Early diagnosis of carpal bone necrosis was possible when the T1 weighted image showed a moderate low intensity signal. A high intensity signal in the T2 weighted image indicated the onset of revascularization, and a favorable prognosis. A normal signal indicated healing of carpal avascular necrosis. MRI was found to be very useful in establishing the diagnosis and in determining the prognosis of carpal osteonecrosis. (author).

  3. Research and advancement of treating avascular necrosis of the femoral head

    International Nuclear Information System (INIS)

    Wang Kaibing; Bai Bin; Wang Honghui; Sui Hong

    2006-01-01

    To undertake retrospective analysis of the research and advancement of treating avascular necrosis of the femoral head. After comparing the superiority and inferiority of different treatments and the present therapeutic status many therapeutic methods for avascular necrosis of the femoral head have been performed, commonly according to the staging of necrosis. Conservative therapy is suitable for stage 0-I, interventional therapy is suitable for stage II-III, operation is adapted for stage II-III and femoral head collapse or degenerative changes. Avascular necrosis of the femoral head is a chronic and dysfunctional illness. Comprehensive treatment according to different stage is now the most popular. Interventional therapy is the study focus of the avascular necrosis of the femoral head meanwhile. (authors)

  4. Temporal Lobe Epilepsy Surgery Failures: A Review

    Science.gov (United States)

    Harroud, Adil; Bouthillier, Alain; Weil, Alexander G.; Nguyen, Dang Khoa

    2012-01-01

    Patients with temporal lobe epilepsy (TLE) are refractory to antiepileptic drugs in about 30% of cases. Surgical treatment has been shown to be beneficial for the selected patients but fails to provide a seizure-free outcome in 20–30% of TLE patients. Several reasons have been identified to explain these surgical failures. This paper will address the five most common causes of TLE surgery failure (a) insufficient resection of epileptogenic mesial temporal structures, (b) relapse on the contralateral mesial temporal lobe, (c) lateral temporal neocortical epilepsy, (d) coexistence of mesial temporal sclerosis and a neocortical lesion (dual pathology); and (e) extratemporal lobe epilepsy mimicking TLE or temporal plus epilepsy. Persistence of epileptogenic mesial structures in the posterior temporal region and failure to distinguish mesial and lateral temporal epilepsy are possible causes of seizure persistence after TLE surgery. In cases of dual pathology, failure to identify a subtle mesial temporal sclerosis or regions of cortical microdysgenesis is a likely explanation for some surgical failures. Extratemporal epilepsy syndromes masquerading as or coexistent with TLE result in incomplete resection of the epileptogenic zone and seizure relapse after surgery. In particular, the insula may be an important cause of surgical failure in patients with TLE. PMID:22934162

  5. Diglycolic acid is the nephrotoxic metabolite in diethylene glycol poisoning inducing necrosis in human proximal tubule cells in vitro.

    Science.gov (United States)

    Landry, Greg M; Martin, Sarah; McMartin, Kenneth E

    2011-11-01

    Diethylene glycol (DEG), a solvent and chemical intermediate, can produce an acute toxic syndrome, the hallmark of which is acute renal failure due to cortical tubular degeneration and proximal tubular necrosis. DEG is metabolized to two primary metabolites, 2-hydroxyethoxyacetic acid (2-HEAA) and diglycolic acid (DGA), which are believed to be the proximate toxicants. The precise mechanism of toxicity has yet to be elucidated, so these studies were designed to determine which metabolite was responsible for the proximal tubule cell death. Human proximal tubule (HPT) cells in culture, obtained from normal cortical tissue and passaged 3-6 times, were incubated with increasing concentrations of DEG, 2-HEAA, or DGA separately and in combination for 48 h at pH 6 or 7.4, and various parameters of necrotic and apoptotic cell death were measured. DEG and 2-HEAA did not produce any cell death. DGA produced dose-dependent necrosis at concentrations above 25 mmol/l. DGA did not affect caspase-3 activity and increased annexin V staining only in propidium iodide-stained cells. Hence, DGA induced necrosis, not apoptosis, as corroborated by severe depletion of cellular adenosine triphosphate levels. DGA is structurally similar to citric acid cycle intermediates that are taken up by specific transporters in kidney cells. HPT cells, incubated with N-(p-amylcinnamoyl)anthranilic acid, a sodium dicarboxylate-1 transporter inhibitor showed significantly decreased cell death compared with DGA alone. These studies demonstrate that DGA is the toxic metabolite responsible for DEG-induced proximal tubular necrosis and suggest a possible transporter-mediated uptake of DGA leading to toxic accumulation and cellular dysfunction.

  6. Atraumatic Pantalar Avascular Necrosis in a Patient With Alcohol Dependence.

    Science.gov (United States)

    Callachand, Fayaz; Milligan, David; Wilson, Alistair

    2016-01-01

    In the United States, an estimated 10,000 to 20,000 new cases of avascular necrosis are diagnosed each year. We present an unusual case of atraumatic avascular necrosis with widespread hindfoot and midfoot involvement. A 62-year-old female with a history of alcohol dependence and smoking, who had previously been treated for avascular necrosis of the knee, presented with right-sided foot pain and difficulty weightbearing. Imaging studies revealed extensive avascular necrosis of the hindfoot and midfoot, which precluded simple surgical intervention. The patient was followed up for 18 months. In the last 8 months of the 18-month period, the patient managed her symptoms using an ankle-foot orthosis. A diagnosis of avascular necrosis should be considered in patients with atraumatic foot and ankle pain, especially in the presence of risk factors such as alcohol excess and smoking. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Development of Web-Based Common Cause Failure (CCF) Database Module for Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun-Gyo; Hwang, Seok-Won; Shin, Tae-young [Korea Hydro and Nuclear Power Co. Ltd., Daejeon (Korea, Republic of)

    2015-05-15

    Probabilistic safety assessment (PSA) has been used to identify risk vulnerabilities and derive the safety improvement measures from construction to operation stages of nuclear power plants. In addition, risk insights from PSA can be applied to improve the designs and operation requirements of plants. However, reliability analysis methods for quantitative PSA evaluation have essentially inherent uncertainties, and it may create a distorted risk profiles because of the differences among the PSA models, plant designs, and operation status. Therefore, it is important to ensure the quality of the PSA model so that analysts identify design vulnerabilities and utilize risk information. Especially, the common cause failure (CCF) has been pointed out as one of major issues to be able to cause the uncertainty related to the PSA analysis methods and data because CCF has a large influence on the PSA results. Organization for economic cooperation and development /nuclear energy agent (OECD/NEA) has implemented an international common cause failure data exchange (ICDE) project for the CCF quality assurance through the development of the detailed analysis methodologies and data sharing. However, Korea Hydro and Nuclear Power company (KHNP) does not have the basis for the data gathering and analysis for CCF analyses. In case of methodology, the Alpha Factor parameter estimation, which can analyze uncertainties and estimate an interface factor (Impact Vector) with an ease, is ready to be applied rather than the Multi Greek Letter (MGL) method. This article summarizes the development of the plant-specific CCF database (DB) module considering the raw data collection and the analysis procedure based on the CCF parameter calculation method of ICDE. Although the portion affected by CCF in the PSA model is quite a large, the development efforts of the tools to collect and analyze data were insufficient. Currently, KHNP intends to improve PSA quality and ensure CCF data reliability by

  8. Development of Web-Based Common Cause Failure (CCF) Database Module for Nuclear Power Plants

    International Nuclear Information System (INIS)

    Lee, Hyun-Gyo; Hwang, Seok-Won; Shin, Tae-young

    2015-01-01

    Probabilistic safety assessment (PSA) has been used to identify risk vulnerabilities and derive the safety improvement measures from construction to operation stages of nuclear power plants. In addition, risk insights from PSA can be applied to improve the designs and operation requirements of plants. However, reliability analysis methods for quantitative PSA evaluation have essentially inherent uncertainties, and it may create a distorted risk profiles because of the differences among the PSA models, plant designs, and operation status. Therefore, it is important to ensure the quality of the PSA model so that analysts identify design vulnerabilities and utilize risk information. Especially, the common cause failure (CCF) has been pointed out as one of major issues to be able to cause the uncertainty related to the PSA analysis methods and data because CCF has a large influence on the PSA results. Organization for economic cooperation and development /nuclear energy agent (OECD/NEA) has implemented an international common cause failure data exchange (ICDE) project for the CCF quality assurance through the development of the detailed analysis methodologies and data sharing. However, Korea Hydro and Nuclear Power company (KHNP) does not have the basis for the data gathering and analysis for CCF analyses. In case of methodology, the Alpha Factor parameter estimation, which can analyze uncertainties and estimate an interface factor (Impact Vector) with an ease, is ready to be applied rather than the Multi Greek Letter (MGL) method. This article summarizes the development of the plant-specific CCF database (DB) module considering the raw data collection and the analysis procedure based on the CCF parameter calculation method of ICDE. Although the portion affected by CCF in the PSA model is quite a large, the development efforts of the tools to collect and analyze data were insufficient. Currently, KHNP intends to improve PSA quality and ensure CCF data reliability by

  9. Idiopathic and diabetic skeletal muscle necrosis: evaluation by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Kattapuram, Taj M.; Suri, Rajeev; Kattapuram, Susan V.; Rosol, Michael S.; Rosenberg, Andrew E.

    2005-01-01

    Idiopathic and diabetic-associated muscle necrosis are similar, uncommon clinical entities requiring conservative management and minimal intervention to avoid complications and prolonged hospitalization. An early noninvasive diagnosis is therefore essential. We evaluated the magnetic resonance imaging (MRI) characteristics of muscle necrosis in 14 patients, in eight of whom the diagnoses were confirmed histologically. Two experienced musculoskeletal radiologists performed retrospective evaluations of the MRI studies of 14 patients with the diagnoses of skeletal muscle infarction. In 10 cases gadolinium-enhanced (T1-weighted fat-suppressed) sequences were available along with T1-weighted, T2-weighted images and STIR sequences, while in four cases contrast-enhanced images were not available. Eight patients had underlying diabetes and in six patients the cause of the myonecrosis was considered idiopathic. T1-weighted images demonstrated isointense swelling of the involved muscle, with mildly displaced fascial planes. There was effacement of the fat signal intensity within the muscle. Fat-suppressed T2-weighted images showed diffuse heterogeneous high signal intensity in the muscles suggestive of edema. Perifascial fluid collection was seen in eight cases. Subcutaneous edema was present in seven patients. Following intravenous gadolinium administration, MRI demonstrated a focal area of heterogeneously enhancing mass with peripheral enhancement. Within this focal lesion, linear dark areas were seen with serpentine enhancing streaks separating them in eight cases. In two cases, a central relatively nonenhancing mass with irregular margins and peripheral enhancement was noted. The peripheral enhancement involved a significant part of the muscle. No focal fluid collection was noted. We believe that the constellation of imaging findings on T1- and T2-weighted images and post-gadolinium sequences is highly suggestive of muscle necrosis. We consider certain specific findings

  10. Mechanisms behind efficacy of tumor necrosis factor inhibitors in inflammatory bowel diseases

    DEFF Research Database (Denmark)

    Olesen, Caroline Meyer; Coskun, Mehmet; Peyrin-Biroulet, Laurent

    2016-01-01

    Biological treatment with tumor necrosis factor (TNF) inhibitors is successful in the management of inflammatory bowel disease (IBD). All TNF inhibitors antagonize the pro-inflammatory cytokine TNF-α but with varying efficacies in IBD. The variations in efficacy probably are caused by structural ...... inhibitors in order to identify mechanisms of importance for their efficacy in IBD. Thus, a better understanding of the mechanistic basis for clinical efficacy can lead to a more rational use of TNF inhibitors in the management of IBD....

  11. Bilateral acute retinal necrosis associated with bilateral uveal effusion in an immunocompetent patient: A challenging association

    Directory of Open Access Journals (Sweden)

    S Bala Murugan

    2018-01-01

    Full Text Available Bilateral uveal effusion syndrome associated with bilateral acute retinal necrosis is a diagnostic and therapeutic challenge. A 52 year old man presented with bilateral angle closure with choroidal detachment. With restricted fundus view, parenteral steroid was started. During close follow up bilateral discrete areas of peripheral retinitis were noted. Parenteral steroids were promptly stopped and parenteral antivirals with oral steroids were continued. It showed healing response with nil recurrences till last follow up. Aggressive treatment of bilateral uveal effusion with parenteral steroids can cause progression of bilateral acute retinal necrosis leading to phthisis bulbi. However early diagnosis, prompt intervention and close follow up are the key elements to therapeutic success even during diagnostic surprises and avoid costly mistakes.

  12. Mammographic and sonographic features of fat necrosis of the breast

    International Nuclear Information System (INIS)

    Upadhyaya, Vidya S; Uppoor, Raghuraj; Shetty, Lathika

    2013-01-01

    Imaging features of fat necrosis vary depending on its stage of evolution and can mimic malignancy in late stages. Imaging may suffice to differentiate fat necrosis in the early stages from malignancy and thus avoid unnecessary biopsy. In this pictorial essay, we present combination of benign features in mammography and/or ultrasonography (USG) that can lead to imaging diagnosis of fat necrosis. The follow-up imaging features of fat necrosis which mirror its pathophysiological evolution have also been demonstrated. To summarize, in the appropriate clinical setting, no mammographic features suspicious for malignancy should be present. When the typical mammographic features are not present, USG can aid with the diagnosis and follow up USG can confirm it

  13. Tumour Necrosis Factor-alpha and Nuclear Factor-kappa B Gene Variants in Sepsis.

    Science.gov (United States)

    Acar, Leyla; Atalan, Nazan; Karagedik, E Hande; Ergen, Arzu

    2018-01-20

    The humoral system is activated and various cytokines are released due to infections in tissues and traumatic damage. Nuclear factor-kappa B dimers are encoded by nuclear factor-kappa B genes and regulate transcription of several crucial proteins of inflammation such as tumour necrosis factor-alpha. To investigate the possible effect of polymorphisms on tumour necrosis factor-alpha serum levels with clinical and prognostic parameters of sepsis by determining the nuclear factor-kappa B-1-94 ins/del ATTG and tumour necrosis factor-alpha (-308 G/A) gene polymorphisms and tumour necrosis factor-alpha serum levels. Case-control study. Seventy-two patients with sepsis and 104 healthy controls were included in the study. In order to determine the polymorphisms of nuclear factor-kappa B-1-94 ins/del ATTG and tumour necrosis factor-alpha (-308 G/A), polymerase chain reaction-restriction fragment length polymorphism analysis was performed and serum tumour necrosis factor-alpha levels were determined using an enzyme-linked immunosorbent assay. We observed no significant differences in tumour necrosis factor-alpha serum levels between the study groups. In the patient group, an increase in the tumour necrosis factor-alpha serum levels in patients carrying the tumour necrosis factor-alpha (-308 G/A) A allele compared to those without the A allele was found to be statistically significant. Additionally, an increase in the tumour necrosis factor-alpha serum levels in patients carrying tumour necrosis factor-alpha (-308 G/A) AA genotype compared with patients carrying the AG or GG genotypes was statistically significant. No significant differences were found in these 2 polymorphisms between the patient and control groups (p>0.05). Our results showed the AA genotype and the A allele of the tumour necrosis factor-alpha (-308 G/A) polymorphism may be used as a predictor of elevated tumour necrosis factor-alpha levels in patients with sepsis.

  14. Cheyne-Stokes respiration in patients with congestive heart failure: causes and consequences.

    Science.gov (United States)

    Lorenzi-Filho, Geraldo; Genta, Pedro R; Figueiredo, Adelaide C; Inoue, Daniel

    2005-08-01

    Cheyne-Stokes respiration is a form of periodic breathing in which central apneas and hypopneas alternate with periods of hyperventilation, producing a waxing and waning pattern of tidal volume. This review focuses on the causes and consequences of Cheyne-Stokes respiration in patients with congestive heart failure, in whom the prevalence is strikingly high and ranges from 30% to 50%. Several factors have been implicated in the genesis of Cheyne-Stokes respiration, including low cardiac output and recurrent hypoxia. The key pathophysiological mechanism triggering Cheyne-Stokes respiration is hyperventilation and low arterial CO2 (PaCO2) that when below the apneic threshold triggers a central apnea. Hyperventilation is associated with pulmonary congestion, and Cheyne-Stokes respiration is more prone to occur during sleep, when the respiratory system is mainly dependent on chemical control. It is associated with recurrent dips in oxygen saturation and arousals from sleep, with oscillations in blood pressure and heart rate, sympathetic activation and increased risk of ventricular tachycardia. Cheyne-Stokes respiration is an independent marker of poor prognosis and may participate in a vicious cycle, further stressing the failing heart.

  15. Cirrhosis is a risk factor for total hip arthroplasty for avascular necrosis

    DEFF Research Database (Denmark)

    Deleuran, Thomas; Overgaard, Søren; Vilstrup, Hendrik

    2016-01-01

    Background and purpose - There are limited data on risk factors for avascular necrosis of the hip, but cirrhosis has been proposed as a risk factor. We examined the association between cirrhosis and incidence of total hip arthroplasty for avascular necrosis. Methods - We used nationwide healthcare......,052 reference individuals. Their median age was 57 years, and 65% were men. 45 cirrhosis patients and 44 reference individuals underwent total hip arthroplasty for avascular necrosis. Cirrhosis patients' HR for a total hip arthroplasty for avascular necrosis was 10 (95% CI: 6-17), yet their 5-year risk...... of avascular necrosis was only 0.2%. For the reference individuals, the 5-year risk was 0.02%. Interpretation - Cirrhosis is a strong risk factor for avascular necrosis of the hip, but it is rare even in cirrhosis patients....

  16. Snow fracture: From micro-cracking to global failure

    Science.gov (United States)

    Capelli, Achille; Reiweger, Ingrid; Schweizer, Jürg

    2017-04-01

    Slab avalanches are caused by a crack forming and propagating in a weak layer within the snow cover, which eventually causes the detachment of the overlying cohesive slab. The gradual damage process leading to the nucleation of the initial failure is still not entirely understood. Therefore, we studied the damage process preceding snow failure by analyzing the acoustic emissions (AE) generated by bond failure or micro-cracking. The AE allow studying the ongoing progressive failure in a non-destructive way. We performed fully load-controlled failure experiments on snow samples presenting a weak layer and recorded the generated AE. The size and frequency of the generated AE increased before failure revealing an acceleration of the damage process with increased size and frequency of damage and/or microscopic cracks. The AE energy was power-law distributed and the exponent (b-value) decreased approaching failure. The waiting time followed an exponential distribution with increasing exponential coefficient λ before failure. The decrease of the b-value and the increase of λ correspond to a change in the event distribution statistics indicating a transition from homogeneously distributed uncorrelated damage producing mostly small AE to localized damage, which cause larger correlated events which leads to brittle failure. We observed brittle failure for the fast experiment and a more ductile behavior for the slow experiments. This rate dependence was reflected also in the AE signature. In the slow experiments the b value and λ were almost constant, and the energy rate increase was moderate indicating that the damage process was in a stable state - suggesting the damage and healing processes to be balanced. On a shorter time scale, however, the AE parameters varied indicating that the damage process was not steady but consisted of a sum of small bursts. We assume that the bursts may have been generated by cascades of correlated micro-cracks caused by localization of

  17. Circuit breaker operation and potential failure modes during an earthquake

    International Nuclear Information System (INIS)

    Lambert, H.E.; Budnitz, R.J.

    1987-01-01

    This study addresses the effect of a strong-motion earthquake on circuit breaker operation. It focuses on the loss of offsite power (LOSP) transient caused by a strong-motion earthquake at the Zion Nuclear Power Plant. This paper also describes the operator action necessary to prevent core melt if the above circuit breaker failure modes occur simultaneously on three 4.16 KV buses. Numerous circuit breakers important to plant safety, such as circuit breakers to diesel generators and engineered safety systems (ESS), must open and/or close during this transient while strong motion is occurring. Potential seismically-induced circuit-breaker failures modes were uncovered while the study was conducted. These failure modes include: circuit breaker fails to close; circuit breaker trips inadvertently; circuit breaker fails to reclose after trip. The causes of these failure modes include: Relay chatter causes the circuit breaker to trip; Relay chatter causes anti-pumping relays to seal-in which prevents automatic closure of circuit breakers; Load sequencer failures. The incorporation of these failure modes as well as other instrumentation and control failures into a limited scope seismic probabilistic risk assessment is also discussed in this paper

  18. Parameter Estimation of a Reliability Model of Demand-Caused and Standby-Related Failures of Safety Components Exposed to Degradation by Demand Stress and Ageing That Undergo Imperfect Maintenance

    Directory of Open Access Journals (Sweden)

    S. Martorell

    2017-01-01

    Full Text Available One can find many reliability, availability, and maintainability (RAM models proposed in the literature. However, such models become more complex day after day, as there is an attempt to capture equipment performance in a more realistic way, such as, explicitly addressing the effect of component ageing and degradation, surveillance activities, and corrective and preventive maintenance policies. Then, there is a need to fit the best model to real data by estimating the model parameters using an appropriate tool. This problem is not easy to solve in some cases since the number of parameters is large and the available data is scarce. This paper considers two main failure models commonly adopted to represent the probability of failure on demand (PFD of safety equipment: (1 by demand-caused and (2 standby-related failures. It proposes a maximum likelihood estimation (MLE approach for parameter estimation of a reliability model of demand-caused and standby-related failures of safety components exposed to degradation by demand stress and ageing that undergo imperfect maintenance. The case study considers real failure, test, and maintenance data for a typical motor-operated valve in a nuclear power plant. The results of the parameters estimation and the adoption of the best model are discussed.

  19. Premature ovarian failure

    OpenAIRE

    Pacheco, José

    2011-01-01

    Premature ovarian failure is characterized by secondary amenorrhea affecting a woman before the age of 40, leading to hypoestrogenism, infertility, and consequences of premature menopause, such as osteoporosis, cardiovascular disease, neurovegetative alterations, and others. Follicular exhaustion is due to either follicles shortage or oocytes accelerated destruction. Main causes are genetic, autoimmune and iatrogenic. Among genetic causes Xq and Xp deletions, translocations, numeric aberratio...

  20. Elevated temperature failures in boiler tubes - case studies

    International Nuclear Information System (INIS)

    Gowrisankar, I.; Bandyopadhyay, G.

    1989-01-01

    Metallurgical investigation of boiler tube failures enables identification of failure mechanisms and the underlying cause related to boiler conditions. Some case studies in short term overheating, prolonged overheating and low cycle fatigue failures in boiler tubes are discussed. (author)