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Sample records for acute glomerulonephritis agn

  1. Acute glomerulonephritis.

    PubMed

    Yoshizawa, N

    2000-09-01

    Acute glomerulonephritis (AGN) is a representative disease of acute nephritic syndrome characterized by the sudden appearance of edema, hematuria, proteinuria, and hypertension. The prototype of AGN is acute poststreptococcal glomerulonephritis (APSGN). "Nephritogenic streptococci" are defined as organisms that are cultured from a patient who develops AGN. Although only a limited number of M-types of streptococci have been recognized as "nephritogenic streptococci", all M-types of streptococci may have nephritogenic potential because the genes for major putative nephritogenic antigens such as SPEB and NAPIr are found to be present in all group A streptococci thus far examined. Pathogenic mechanisms for APSGN involving both humoral and cell-mediated immunity have been recently proposed. The role of humoral immunity is presumed to be mediated by the in situ formation of nephritogenic streptococcal antigen-antibody complexes and circulating immune complexes. While in the cellular immune component a role for delayed-type hypersensitivity has been suggested to contribute to the pathogenesis of APSGN. PMID:10969898

  2. Glomerulonephritis

    MedlinePlus

    ... that suppress the immune system A procedure called plasmapheresis may sometimes be used for glomerulonephritis caused by ... Saunders; 2012:chap 32. Cattran DC, Reigh HN. Overview of therapy for glomerular disease. In: Taal MW, ...

  3. Cerebral venous thrombosis in a patient with acute postinfectious glomerulonephritis.

    PubMed

    Morkhandikar, S; Priyamvada, P S; Srinivas, B H; Parameswaran, S

    2016-01-01

    Thrombosis of the cerebral venous sinuses (CVT) is described in nephrotic syndrome. A 13-year-old girl was admitted with acute post-infectious glomerulonephritis (APIGN). Subsequently she developed recurrent seizures with focal neurological deficits. On evaluation, she was found to have CVT. To the best of our knowledge, this is the first report of CVT in APIGN. Identifying this complication is imperative, as timely diagnosis and treatment could be lifesaving. PMID:27194837

  4. Pathogenic mechanism of acute post-streptococcal glomerulonephritis.

    PubMed

    Nordstrand, A; Norgren, M; Holm, S E

    1999-01-01

    Considerable knowledge has been accumulated regarding the characteristics of acute post-streptococcal glomerulonephritis (APSGN), and many attempts have been made to identify a streptococcal factor or factors responsible for triggering this disease. However, the pathogenic mechanism behind APSGN remains largely unknown. As glomerular deposition of C3 is generally demonstrated before that of IgG in the disease process, it is likely that the inflammatory response is initiated by renal deposition of a streptococcal product, rather than by deposition of antibodies or pre-formed immune complexes. During recent years, a number of streptococcal products have been suggested to be involved in the pathogenic process. In this review, possible roles of these factors are discussed in the context of the clinical and renal findings most often demonstrated in patients with APSGN. Streptokinase was observed to be required in order to induce signs of APSGN in mice, and a number of findings suggest that the initiation of the disease may occur as a result of renal binding by certain nephritis-associated variants of this protein. However, additional factors may be required for the development of the disease. PMID:10680980

  5. HBV-Associated Postinfectious Acute Glomerulonephritis: A Report of 10 Cases

    PubMed Central

    Zhang, Yong; Li, Junxia; Peng, Weihua; Yu, Guoqing; Wang, Liping; Chen, Jian; Zheng, Feng

    2016-01-01

    Postinfectious acute glomerulonephritis (PIGN) may occur after various bacterial and viral infections. Hepatitis B virus (HBV) infection is a cause of chronic glomerulonephritis. We report here 10 cases (ages 7–20 years-old) of chronic HBV carriers with acute glomerulonephritis, with positive glomerular staining of hepatitis B surface antigen, and detectable presence of HBV DNA in the glomeruli. This form of PIGN, HBV-PIGN, has not been previously identified. To further characterize clinical and pathological features of HBV- PIGN, we selected 10 cases of age-matched non-HBV PIGN for comparison. While both HBV associated PIGN and non-HBV PIGN similarly presented as proteinuria, hematuria, and hypertension, there was a trend of higher acute kidney injury and worsened prognosis in HBV-PIGN. 6 months after the onset, 4 patients with HBV associated PIGN did not show improvement from the disease, whereas all patients with non-HBV PIGN had complete or partial recovery. Pathologically, both HBV associated PIGN and non-HBV PIGN showed typical diffuse glomerular endocapillary proliferation, but HBV associated PIGN differed from classical PIGN with much fewer sub-epithelial glomerular “hump-shape” immune complex depositions. In conclusion, we have identified a novel association of HBV infection with acute glomerulonephritis. PMID:27512989

  6. Membranoproliferative glomerulonephritis

    MedlinePlus

    Membranoproliferative GN I; Membranoproliferative GN II; Mesangiocapillary glomerulonephritis; Membranoproliferative glomerulonephritis; Lobular GN; Glomerulonephritis - membranoproliferative; MPGN type I; MPGN type ...

  7. Coexistence of Acute Crescent Glomerulonephritis and IgG4-Related Kidney Disease

    PubMed Central

    Lu, Zeyuan; Yin, Jianyong; Bao, Hongda; Jiao, Qiong; Wu, Huijuan; Wu, Rui; Xue, Qin; Wang, Niansong; Zhang, Zhigang; Wang, Feng

    2016-01-01

    Introduction IgG4-related disease (IgG4-RD) is a fibroinflammatory disorder that may involve almost each organ or system. IgG4-related kidney disease (IgG4-RKD) refers to renal lesions associated with IgG4-RD. The most frequent morphological type of renal lesions is IgG4-related tubulointerstitial nephritis (IgG4-TIN) which is associated with increased IgG4-positive plasma cell infiltration and interstitial fibrosis. Case Report Herein, we present a rare case with coexisting IgG4-RKD and acute crescent glomerulonephritis with concomitant severe tubulointerstitial lesions instead of classic IgG4-TIN. Conclusion IgG4-RKD and acute crescent glomerulonephritis can occur in the same patient. This case may give us a clearer viewpoint of the disease. PMID:27504450

  8. Acute glomerulonephritis in children of the Niger Delta region of Nigeria.

    PubMed

    McGil Ugwu, G I

    2015-09-01

    A three-year retrospective study was conducted to determine the incidence, pattern of presentation and other clinical and biochemical features as well as outcome of treatment of patients admitted with acute glomerulonephritis at the Delta State University Teaching Hospital, Oghara and GN Children's Clinic, Warri. The case notes of all the children who presented with renal diseases from January 2010 to December 2012 were retrieved and those with acute glomerulonephritis were analyzed. A total of 20 patients (13 male and seven female) with acute glomerulonephritis were seen during the three-year period under review. Twelve patients (60%) were from the low socioeconomic class, six (30%) from the middle class and only two (10%) were from the high-income group. The presentation of the illness was most common between October and January. The age range of the patients was three to 13 years, with an average age of eight years. Seventeen (85%) of the patients were in the school-going age group (>5 years to 10 years). The most common symptom/sign noted was anemia in 90% of the patients, followed by oliguria/anuria and edema seen in 80% of the patients. Seventy percent of the patients had cola-colored urine, while 55% had hypertension. Some patients gave a history suggestive of previous streptococcal infection. More patients had sore throat (25%) than skin infection (10%). All the patients had proteinuria, while 90% had hematuria. The most common complication was acute kidney injury, seen in eight (40%) of the patients, followed by hypertensive encephalopathy, which occurred in three (15%) patients. Most patients (60%) were hospitalized for one to two weeks. The outcome of the management of these patients showed 14 (70%) of the patients recovered fully while three (15%) had persistent hematuria and two (10%) had persistent proteinuria. Ninety-five percent of the patients recovered from the acute illness and one patient (5%), a boy aged nine years old, died. PMID:26354592

  9. Diffuse alveolar hemorrhage in a patient with acute poststreptococcal glomerulonephritis caused by impetigo.

    PubMed

    Yoshida, Masahiro; Yamakawa, Hideaki; Yabe, Masami; Ishikawa, Takeo; Takagi, Masamichi; Matsumoto, Kei; Hamaguchi, Akihiko; Ogura, Makoto; Kuwano, Kazuyoshi

    2015-01-01

    We herein report a case of pulmonary renal syndrome with nephritis in a 17-year-old boy with diffuse alveolar hemorrhage (DAH) associated with acute poststreptococcal glomerulonephritis (APSGN). The patient exhibited hemoptysis two weeks after developing impetigo, and DAH was diagnosed on bronchoscopy. Respiratory failure progressed, and high-dose methylprednisolone therapy was administered; the respiratory failure regressed immediately after the onset of therapy. Streptococcus pyogenes was detected in an impetigo culture, and, together with the results of the renal biopsy, a diagnosis of APSGN was made. This case demonstrates the effects of high-dose methylprednisolone therapy in improving respiratory failure. PMID:25876581

  10. IL-17 Expression in the Time Course of Acute Anti-Thy1 Glomerulonephritis

    PubMed Central

    Loof, Tanja; Krämer, Stephanie; Gaedeke, Jens; Neumayer, Hans-Hellmut; Peters, Harm

    2016-01-01

    Background Interleukin-17 (IL-17) is a new pro-inflammatory cytokine involved in immune response and inflammatory disease. The main source of IL-17 is a subset of CD4+ T-helper cells, but is also secreted by non-immune cells. The present study analyzes expression of IL-17 in the time course of acute anti-thy1 glomerulonephritis and the role of IL-17 as a potential link between inflammation and fibrosis. Methods Anti-thy1 glomerulonephritis was induced into male Wistar rats by OX-7 antibody injection. After that, samples were taken on days 1, 5, 10 (matrix expansion phase), 15 and 20 (resolution phase). PBS-injected animals served as controls. Proteinuria and histological matrixes score served as the main markers for disease severity. In in vitro experiments, NRK-52E cells were used. For cytokine expressions, mRNA and protein levels were analyzed by utilizing RT-PCR, in situ hybridization and immunofluorescence. Results Highest IL-17 mRNA-expression (6.50-fold vs. con; p<0.05) was found on day 5 after induction of anti-thy1 glomerulonephritis along the maximum levels of proteinuria (113 ± 13 mg/d; p<0.001), histological glomerular-matrix accumulation (82%; p<0.001) and TGF-β1 (2.2-fold; p<0.05), IL-6 mRNA expression (36-fold; p<0.05). IL-17 protein expression co-localized with the endothelial cell marker PECAM in immunofluorescence. In NRK-52E cells, co-administration of TGF-β1 and IL-6 synergistically up-regulated IL-17 mRNA 4986-fold (p<0.001). Conclusions The pro-inflammatory cytokine IL-17 is up-regulated in endothelial cells during the time course of acute anti-thy1 glomerulonephritis. In vitro, NRK-52E cells secrete IL-17 under pro-fibrotic and pro-inflammatory conditions. PMID:27243813

  11. Mesangial proliferative glomerulonephritis with acute tubule interstitial nephritis leading to acute kidney injury in influenza A (H1N1) infection

    PubMed Central

    Kute, V. B.; Vanikar, A. V.; Shah, P. R.; Gumber, M. R.; Patel, H. V.; Trivedi, H. L.

    2014-01-01

    Respiratory complications and renal failure are the leading causes for morbidity and mortality due to influenza (H1N1) virus infection. There has been limited information on histopathology of H1N1 influenza-related acute kidney injury (AKI). We describe AKI with H1N1 infection in a 52-year-old female. Renal biopsy showed mesangial proliferative glomerulonephritis with acute tubule interstitial nephritis. Her condition improved rapidly with oseltamivir, fluid replacement, steroid and dialysis. Our case suggests that H1N1 infection may have a causative link to the development of mesangial proliferative glomerulonephritis with acute tubulointerstitial nephritis. PMID:24701045

  12. IgA-dominant acute poststreptococcal glomerulonephritis with concomitant rheumatic fever successfully treated with steroids: a case report

    PubMed Central

    Rus, Rina R; Toplak, Nataša; Vizjak, Alenka; Mraz, Jerica; Ferluga, Dušan

    2015-01-01

    There are only a few reports of the co-occurrence of acute poststreptococcal glomerulonephritis (APGN) and acute rheumatic fever. We report an unusual case of a 3-year-old boy with nephrotic syndrome and acute renal failure with the transitional need for peritoneal dialysis, biopsy-proven atypical IgA-dominant APGN, and concomitant acute rheumatic fever, successfully treated by steroids. Aggressive treatment with pulses of methylprednisolone proved to be successful and we recommend its use in this type of cases. PMID:26718763

  13. IgA-dominant acute poststreptococcal glomerulonephritis with concomitant rheumatic fever successfully treated with steroids: a case report.

    PubMed

    Rus, Rina R; Toplak, Nataša; Vizjak, Alenka; Mraz, Jerica; Ferluga, Dušan

    2015-12-01

    There are only a few reports of the co-occurrence of acute poststreptococcal glomerulonephritis (APGN) and acute rheumatic fever. We report an unusual case of a 3-year-old boy with nephrotic syndrome and acute renal failure with the transitional need for peritoneal dialysis, biopsy-proven atypical IgA-dominant APGN, and concomitant acute rheumatic fever, successfully treated by steroids. Aggressive treatment with pulses of methylprednisolone proved to be successful and we recommend its use in this type of cases. PMID:26718763

  14. Acute Glomerulonephritis in a Child with Chlamydia pneumoniae Infection: A Case Report

    PubMed Central

    Falsaperla, Raffaele; Giunta, Leandra; Spataro, Giuseppina; Rapisarda, Venerando; Velardita, Mario; Nunnari, Giuseppe; Pavone, Piero

    2013-01-01

    Background. Infectious diseases seem to be an important and independent risk factor for renal failure, but the underlying mechanism of renal involvement during some kinds of infectious diseases is still unclear, even if the literature data report immunomediated and/or autoimmune mechanisms to explain the pathogenic relationship between the two diseases. In paediatric patients, Chlamydia pneumoniae is a rare cause of renal complications and it may manifest in several ways, mainly involving the respiratory system, even if also renal and glomerulalr complications, have been described. Case Diagnosis/Treatment. Herein we report a case of a 3-year-old child who developed an acute glomerulonephritis that was chronologically, clinically, and biologically related to a previous Chlamydia pneumoniae infection. On our knowledge, in the literature it is the youngest patient with renal involvement during course of Chlamydia pneumoniae infection ever reported. Conclusions. The present case supports the hypothesis of a rather close causal relationship between this infective agent and renal and glomerular symptoms occurred in this child, during an acute episode of respiratory disease. PMID:23970901

  15. Acute Glomerulonephritis in a Child with Chlamydia pneumoniae Infection: A Case Report.

    PubMed

    Vitaliti, Giovanna; Falsaperla, Raffaele; Giunta, Leandra; Spataro, Giuseppina; Rapisarda, Venerando; Velardita, Mario; Nunnari, Giuseppe; Pavone, Piero

    2013-01-01

    Background. Infectious diseases seem to be an important and independent risk factor for renal failure, but the underlying mechanism of renal involvement during some kinds of infectious diseases is still unclear, even if the literature data report immunomediated and/or autoimmune mechanisms to explain the pathogenic relationship between the two diseases. In paediatric patients, Chlamydia pneumoniae is a rare cause of renal complications and it may manifest in several ways, mainly involving the respiratory system, even if also renal and glomerulalr complications, have been described. Case Diagnosis/Treatment. Herein we report a case of a 3-year-old child who developed an acute glomerulonephritis that was chronologically, clinically, and biologically related to a previous Chlamydia pneumoniae infection. On our knowledge, in the literature it is the youngest patient with renal involvement during course of Chlamydia pneumoniae infection ever reported. Conclusions. The present case supports the hypothesis of a rather close causal relationship between this infective agent and renal and glomerular symptoms occurred in this child, during an acute episode of respiratory disease. PMID:23970901

  16. Focal mesangial-sclerosing glomerulonephritis and acute-spontaneous infectious canine hepatitis: structural, immunohistochemical and subcellular studies.

    PubMed

    Hervás, J; Gómez-Villamandos, J C; Pérez, J; Carrasco, L; Sierra, M A

    1997-06-01

    The glomerular alterations observed in a dog with acute spontaneous infectious canine hepatitis (ICH) are described. Histologic changes of the glomeruli were enlargement of the mesangium with presence of intranuclear inclusion bodies and without proliferation of mesangial cells. Electron microscopy revealed adenovirus replication sites in glomerular mesangial cells and in endothelial cells of glomerular capillaries, as well as a focal mesangial-sclerosing glomerulonephritis associated with electron dense deposits which were closely related with extracellular ICH viral particles and immunohistochemically reactive for immunoglobulin (Ig) G, IgA, IgM and C3c complement components. PMID:9239835

  17. Acute nephritic syndrome

    MedlinePlus

    Glomerulonephritis - acute; Acute glomerulonephritis; Nephritis syndrome - acute ... Acute nephritic syndrome is often caused by an immune response triggered by an infection or other disease. Common causes ...

  18. New trends of an old disease: the acute post infectious glomerulonephritis at the beginning of the new millenium.

    PubMed

    Stratta, Piero; Musetti, Claudio; Barreca, Antonella; Mazzucco, Gianna

    2014-06-01

    The association between acute renal disease and infection has been known since the mid '800s: acute post-infectious glomerulonephritis (PIGN) is a reactive immunological process against the kidney secondary to an infection, classically caused by a Streptococcus. The typical clinical presentation of PIGN is an acute nephritic syndrome with macro- or microscopic hematuria, proteinuria, hypertension, edema and renal function impairment of variable degree. The histology is characterized by an intracapillary glomerular proliferation, but may rarely be associated with an extracapillary proliferation. The classical childhood form is still present nowadays, even with severe cases, in developing countries, while in the last decades it almost disappeared in industrialized countries, where post-infectious GN are often found in elderly patients with multiple comorbidities. These clinical variants are usually related to other infective agents, like Staphylococcus aureus, both methicillin resistant (MRSA) and susceptible, and may be characterized by an IgA-dominant deposition. Kidney biopsy is rarely needed, especially in the child, while in the adult or old patient a biopsy is warranted if there is an atypical presentation or evolution, like rapidly progressive renal failure, absent or delayed function recovery, persisting low C3, nephrotic range proteinuria and persisting high proteinuria. Current therapy strategies rely on culture-guided systemic antibiotics, especially in the old patient, in which MRSA are relatively frequent, support therapy and only in very selected cases on steroids. These latter cases include the rare PIGN with crescents and those with a severe interstitial inflammation. PMID:24777751

  19. Recurrent Glomerulonephritis after Renal Transplantation: An Unsolved Problem

    PubMed Central

    Golgert, William A.; Appel, Gerald B.; Hariharan, Sundaram

    2008-01-01

    Background and objectives: Despite advances in prevention of acute rejection and improved short- and long-term kidney graft survival, recurrent glomerulonephritis remains problematic and poorly characterized. This study analyzed prevalence and outcome of recurrent glomerulonephritis from various registries. Design, setting, participants, & measurements: Definition, classification, and limitations in evaluating epidemiology of native and recurrent glomerulonephritis are discussed. Epidemiology of native glomerulonephritis as the cause of end-stage renal failure and subsequent recurrence of individual glomerulonephritis was evaluated using data from various registries, and pathogenesis of individual glomerulonephritis is discussed. Results: Analysis of data from transplant registries revealed that glomerulonephritis is an important cause of end-stage renal disease in white and pediatric recipients; however, glomerulonephritis as the cause of end-stage renal disease is not characterized well in black recipients, and many of them are perhaps labeled to have hypertensive nephrosclerosis as the cause of renal disease without renal biopsy. A systematic approach toward urinalysis after transplantation and utility of immunofluorescence and electron microscopic examination of renal biopsy tissues will identify the true prevalence of recurrent glomerulonephritis. Data on recurrent glomerulonephritis should be compiled by either using registry analysis or pooling data from multiple centers. This will provide true data on prevalence and outcome and could potentially initiate translational research studies. Conclusions: The understanding of the pathogenesis of recurrent glomerulonephritis is critical to optimize prevention as well as to treat individual recurrent glomerulonephritis, which can enhance long-term graft survival. PMID:18272827

  20. Temporal Changes in Post-Infectious Glomerulonephritis in Japan (1976-2009)

    PubMed Central

    Usui, Joichi; Tawara-Iida, Takashi; Takada, Kenji; Ebihara, Itaru; Ueda, Atsushi; Iwabuchi, Satoshi; Ishizu, Takashi; Iitsuka, Tadashi; Takemura, Katsumi; Kawamura, Tetsuya; Kaneko, Shuzo; Sakai, Kentaro; Kai, Hirayasu; Gomibuchi, Tomoka; Nagata, Michio; Kobayashi, Masaki; Koyama, Akio; Suka, Machi; Radhakrishnan, Jai; Yamagata, Kunihiro

    2016-01-01

    Background The incidence of post-infectious glomerulonephritis (PIGN) in developed countries has decreased over the last 50 years. Here we identified the trends of the incidence of PIGN in Japan during the past four decades. Methods We explored the frequency, clinicopathological findings, and prognosis of PIGN based on 6,369 cases from the Renal Biopsy Database of our institute in the Kanto region of Japan, diagnosed histologically from 1976 to 2009. Results The numbers of PIGN cases were 131 (2.1%) in total, and 2.4%, 1.1%, 2.6% and 2.1% identified in the 1970s, 1980s, 1990s, and 2000s, respectively. Acute glomerulonephritis (AGN), including post-streptococcal glomerulonephritis (PSGN), accounted for almost all of the PIGN cases in the 1970s, but decreased to approx. 40%–50% since the 1990s. In the 1990s, Staphylococcus aureus infection-related nephritis (SARN) showed a rapid increase in rate, reaching 30%. The incidence of hepatitis C virus infection-associated GN (HCVGN) has increased since the 1990s. The average age at onset rose from 33 to 51 years over the study period. These transitions can be summarized as increases in SARN and HCVGN and decreases in PSGN and other types of AGN, since SARN and HCVGN have older onsets compared to PSGN and other AGN types. The clinicopathological features were marked for each PIGN. Regarding the prognosis, the renal death rates of both the SARN and HCVGN groups were significantly higher than those of other PIGN. Conclusion Based on our analysis of the Renal Biopsy Database, the incidence of PIGN in Japan reached its peak in the 1990s. The temporal changes in the incidence of PIGN reflected the trends in infectious diseases of each decade and the continual aging of the population, with a related higher susceptibility to infections. PMID:27286043

  1. Acute tubular necrosis as a part of vancomycin induced drug rash with eosinophilia and systemic symptoms syndrome with coincident postinfectious glomerulonephritis

    PubMed Central

    Kim, Kyung Min; Sung, Kyoung; Yang, Hea Koung; Kim, Seong Heon; Kim, Hye Young; Ban, Gil Ho; Park, Su Eun; Lee, Hyoung Doo

    2016-01-01

    Drug rash with eosinophilia and systemic symptoms (DRESS) syndrome is a rare and potentially fatal condition characterized by skin rash, fever, eosinophilia, and multiorgan involvement. Various drugs may be associated with this syndrome including carbamazepine, allopurinol, and sulfasalazine. Renal involvement in DRESS syndrome most commonly presents as acute kidney injury due to interstitial nephritis. An 11-year-old boy was referred to the Children's Hospital of Pusan National University because of persistent fever, rash, abdominal distension, generalized edema, lymphadenopathy, and eosinophilia. He previously received vancomycin and ceftriaxone for 10 days at another hospital. He developed acute kidney injury with nephrotic range proteinuria and hypocomplementemia. A subsequent renal biopsy indicated the presence of acute tubular necrosis (ATN) and late exudative phase of postinfectious glomerulonephritis (PIGN). Systemic symptoms and renal function improved with corticosteroid therapy after the discontinuation of vancomycin. Here, we describe a biopsy-proven case of severe ATN that manifested as a part of vancomycin-induced DRESS syndrome with coincident PIGN. It is important for clinicians to be aware of this syndrome due to its severity and potentially fatal nature. PMID:27186222

  2. Adalimumab (TNFα Inhibitor) Therapy Exacerbates IgA Glomerulonephritis Acute Renal Injury and Induces Lupus Autoantibodies in a Psoriasis Patient

    PubMed Central

    Wei, S. S.; Sinniah, R.

    2013-01-01

    Adalimumab (Humira) is a tumour necrosis factor α (TNFα) inhibitor that is approved for the treatment of rheumatoid arthritis, psoriasis, psoriatic arthritis, Crohn's disease, ankylosing spondylitis, and juvenile idiopathic arthritis (Sullivan and Preda (2009), Klinkhoff (2004), and Medicare Australia). Use of TNFα inhibitors is associated with the induction of autoimmunity (systemic lupus erythematosus, vasculitis, and sarcoidosis or sarcoid-like granulomas) (Ramos-Casals et al. (2010)). We report a patient with extensive psoriasis presenting with renal failure and seropositive lupus markers without classical lupus nephritis after 18 months treatment with adalimumab. He has renal biopsy proven IgA nephritis instead. Renal biopsy is the key diagnostic tool in patients presenting with adalimumab induced nephritis and renal failure. He made a remarkable recovery after adalimumab cessation and steroid treatment. To our knowledge, this is a unique case of a psoriasis patient presenting with seropositive lupus markers without classical lupus nephritis renal failure and had renal biopsy proven IgA glomerulonephritis after receiving adalimumab. PMID:24558628

  3. Metabolic Syndrome in IgA Glomerulonephritis

    PubMed Central

    Kaartinen, Kati; Syrjänen, Jaana; Pörsti, Ilkka; Harmoinen, Aimo; Huhtala, Heini; Mustonen, Jukka

    2014-01-01

    Background/Aims Metabolic syndrome (MetS) may have an independent impact on the development of chronic kidney disease. This study examines the prevalence of MetS in subjects with IgA glomerulonephritis (IgAGN) and its impact on disease progression in a retrospective fashion. Patients and Methods Altogether, 174 subjects (104 males) were examined 11 years (first visit) after IgAGN diagnosis and again after 16 years (second visit; 144 subjects responded). Different glomerular filtration markers were utilized. The MetS criteria by Alberti et al. [Circulation 2009;120:1640-1645] were applied, in which the presence of any three of five risk factors (elevated waist circumference, triglycerides, glucose, existence of hypertension, or reduced high-density lipoprotein cholesterol) constitutes the diagnosis. Results The prevalence of MetS at the first visit was 39%, corresponding to that of the general Finnish population. In univariate analyses, MetS was significantly associated with the progression of IgAGN at the second visit. However, in multivariate analyses, the existence of MetS was not a significant prognostic determinant. Conclusion The number of subjects with MetS among IgAGN patients and the general population is equal in Finland. MetS does not seem to be an independent prognostic variable. PMID:25337083

  4. [Glomerulonephritis in dogs and cats].

    PubMed

    Reinacher, M; Frese, K

    1991-04-01

    Immunohistology and special staining of plastic sections allow diagnosis and differentiation of subtypes of glomerulonephritis in dogs. Frequency and clinical importance of these forms of glomerulonephritis vary significantly. In cats, glomerulonephritis occurs frequently in FIV-positive cats but is rare in animals suffering from persistent FeLV infection or FIP. PMID:2068715

  5. Factor VIII and glomerulonephritis.

    PubMed

    Ekberg, M; Nilsson, I M

    1975-05-17

    To find out if determination of factor VIII,which most probably is synthetised in the intima of blood-vessesls, is of value for predicting the severity of vessel damge in glomerulonephritis, factor-VIII activity, factor-VIII-related antigen, and glomerular filtration-ratewere esto,ated om 85 patients with early glomerulonephritis on admission, and in 70 of these at follow-up for up to 4 years. The levels of factor-VIII activity and factor-VIII-related antigen on admission were normal in those patients who recovered. Where renal function was impaired on admission or becaome so during follow-up, factor VIII was high. Determination of factor VIII might thus be of prognostic value in early glomerulonephritis. PMID:49471

  6. Update on endocarditis-associated glomerulonephritis.

    PubMed

    Boils, Christie L; Nasr, Samih H; Walker, Patrick D; Couser, William G; Larsen, Christopher P

    2015-06-01

    Glomerulonephritis (GN) due to infective endocarditis (IE) is well documented, but most available data are based on old autopsy series. To update information, we now present the largest biopsy-based clinicopathologic series on IE-associated GN. The study group included 49 patients (male-to-female ratio of 3.5:1) with a mean age of 48 years. The most common presenting feature was acute kidney injury. Over half of the patients had no known prior cardiac abnormality. However, the most common comorbidities were cardiac valve disease (30%), intravenous drug use (29%), hepatitis C (20%), and diabetes (18%). The cardiac valve infected was tricuspid in 43%, mitral in 33%, and aortic in 29% of patients. The two most common infective bacteria were Staphylococcus (53%) and Streptococcus (23%). Hypocomplementemia was found in 56% of patients tested and ANCA antibody in 28%. The most common biopsy finding was necrotizing and crescentic GN (53%), followed by endocapillary proliferative GN (37%). C3 deposition was prominent in all cases, whereas IgG deposition was seen in <30% of cases. Most patients had immune deposits detectable by electron microscopy. Thus, IE-associated GN most commonly presents with AKI and complicates staphylococcal tricuspid valve infection. Contrary to infection-associated glomerulonephritis in general, the most common pattern of glomerular injury in IE-associated glomerulonephritis was necrotizing and crescentic glomerulonephritis. PMID:25607109

  7. Properdin and C3 Proactivator: Alternate Pathway Components in Human Glomerulonephritis

    PubMed Central

    McLean, Robert H.; Michael, Alfred F.

    1973-01-01

    Serological and immunopathological studies of human glomerulonephritis have suggested that alternate pathways of activation of the third component of complement may be important in some forms of glomerulonephritis. We have investigated the role of two alternate pathway proteins, properdin and C3 proactivator, in 22 patients with chronic membranoproliferative glomerulonephritis, 21 patients with systemic lupus erythematosus, 20 patients with acute poststreptococcal glomerulonephritis, and 19 patients with other forms of renal disease. C3 (measured at β1A), properdin, and C3 proactivator were assayed by single radial immunodiffusion. In sera with low β1A (< 2 SD), mean properdin was most significantly decreased in patients with acute poststreptococcal glomerulonephritis but was also significantly decreased in chronic membranoproliferative glomerulonephritis and in untreated systemic lupus erythematosus. Properdin levels in other renal disease, acute glomerulonephritis, and chronic membranoproliferative glomerulonephritis with normal β1A levels were not significantly different from normal. A positive correlation between β1A and properdin levels in individual sera was present in all diseases except systemic lupus erythematosus. Serum C3 proactivator was markedly decreased in active systemic lupus erythematosus and there was a positive correlation between β1A and C3 proactivator levels in systemic lupus erythematosus and other renal diseases but not acute poststreptococcal glomerulonephritis. Properdin in fresh sera from four patients with systemic lupus erythematosus and five with chronic membranoproliferative glomerulonephritis showed increased migration toward the cathode on immunoelectrophoresis, suggesting in vivo change of the properdin molecule. The observation of reduced serum levels of properdin and C3 proactivator and altered electrophoretic migration of properdin in some patients with glomerulonephritis provide new evidence for participation of these

  8. Neutrophils: game changers in glomerulonephritis?

    PubMed Central

    Mayadas, Tanya N.; Rosetti, Florencia; Ernandez, Thomas; Sethi, Sanjeev

    2010-01-01

    Glomerulonephritides represent a diverse array of diseases that have in common immune cell-mediated effector mechanisms that cause organ damage. The contribution of neutrophils to the pathogenesis of proliferative glomerulonephritis (GN) is not well recognized. Most equate neutrophils with killing pathogens and causing collateral tissue damage during acute inflammation. However, these phagocytes are endowed with additional characteristics that have been traditionally reserved for cells of the adaptive immune system. They communicate with other cells, exhibit plasticity in their responses and have the potential to coordinate and inform the subsequent immune response, thus countering the notion that they arrive, destroy and then disappear. Therefore, neutrophils, which are the first to arrive at a site of inflammation, are potential game changers in GN. PMID:20667782

  9. Hypercoagulation in glomerulonephritis.

    PubMed Central

    Salem, H H; Whitworth, J A; Koutts, J; Kincaid-Smith, P S; Firkin, B G

    1981-01-01

    The clotting values of 50 patients with glomerulonephritis were examined. Three different coagulation groups were recognised: those with normal clotting values (group 1); those with high concentrations of factor VIII but otherwise normal clotting results (group 2); and patients who showed the presence of an activator of the intrinsic coagulation pathway, indicated by the presence of a short activated partial thromboplastin time or the ability of patients' plasma to shorten control clotting time in mixing studies (group 3). Patients in group 2 either had a uniform rise in all three components of the factor VIII molecule or a disproportionately higher concentration of factor-VIII-related antigen. In contrast, the level of VIII clotting activity in patients in group 3 was always higher than concentrations of either VIIIAg or VIIIWF. A significantly high incidence of thrombotic complications was observed in patients with group 3 but in none of the patients in either group 1 or group 2. Impaired renal function was more common in patients in groups 2 and 3, with higher mean serum creatinine concentrations in those with group 3. Patients with glomerulonephritis who have a short partial thromboplastin time with kaolin or who shorten control clotting time form a subgroup in whom hypercoagulation could adversely affect the course of their disease. The value of antiplatelet or anticoagulant treatment in these patients needs to be explored. PMID:6788212

  10. Cryoglobulinemic Glomerulonephritis as a Presentation of Atypical Post-Infectious Glomerulonephritis

    PubMed Central

    Boumitri, Christine; Haddad, Fady G.; Rondla, Chetana; El-Sayegh, Suzanne; El-Charabaty, Elie

    2016-01-01

    Post-infectious glomerulonephritis (PIGN) usually occurs within few days to weeks following an infection. Clinical presentation is variable, but in general, it is considered a benign entity with good prognosis. It rarely requires kidney biopsy to confirm the diagnosis. We present a case of a 55-year-old, previously healthy, male who presented for worsening shortness of breath, persistent cough, and right-sided pleuritic chest pain. Initial workup revealed a right exudative effusion with empyema. Hospital course was complicated by acute kidney injury requiring renal replacement therapy with a peak creatinine of 10.2 mg/dL from a baseline of 1.18 mg/dL. On kidney biopsy, findings were compatible with a diagnosis of cryoglobulinemic glomerulonephritis or an atypical form of PIGN. While a wide variety of histopathological findings on renal biopsies have been described to complement the usual diffuse proliferative glomerulonephritis pattern, cryoglobulinemic features with negative cryoglobulin have never been reported. Our case is unique not only by having an atypical histological presentation but also by meeting the criteria of atypical PIGN with persistent hypertension and microscopic hematuria. PMID:26668683

  11. Hypertension in Chronic Glomerulonephritis.

    PubMed

    Ihm, Chun-Gyoo

    2015-12-01

    Chronic glomerulonephritis (GN), which includes focal segmental glomerulosclerosis and proliferative forms of GN such as IgA nephropathy, increases the risk of hypertension. Hypertension in chronic GN is primarily volume dependent, and this increase in blood volume is not related to the deterioration of renal function. Patients with chronic GN become salt sensitive as renal damage including arteriolosclerosis progresses and the consequent renal ischemia causes the stimulation of the intrarenal renin-angiotensin-aldosterone system(RAAS). Overactivity of the sympathetic nervous system also contributes to hypertension in chronic GN. According to the KDIGO guideline, the available evidence indicates that the target BP should be ≤140mmHg systolic and ≤90mmHg diastolic in chronic kidney disease patients without albuminuria. In most patients with an albumin excretion rate of ≥30mg/24 h (i.e., those with both micro-and macroalbuminuria), a lower target of ≤130mmHg systolic and ≤80mmHg diastolic is suggested. The use of agents that block the RAAS system is recommended or suggested in all patients with an albumin excretion rate of ≥30mg/ 24 h. The combination of a RAAS blockade with a calcium channel blocker and a diuretic may be effective in attaining the target BP, and in reducing the amount of urinary protein excretion in patients with chronic GN. PMID:26848302

  12. Comparative pathology of glomerulonephritis in animals.

    PubMed

    Slauson, D O; Lewis, R M

    1979-03-01

    Glomerulonephritis constitutes an important category of renal diseases in animals and has been recognized with increasing frequency in the last decade. We report here the comparative morphologic aspects of glomerulonephritis as a naturally occurring disease of animals. We briefly review the immunopathogenesis of glomerulonephritis. The morphology of renal lesions occurring in glomerulonephritis in dogs, cats, cattle, sheep, horses and swine has been reviewed with emphasis on the range and specificity of various glomerular lesions and on the comparison of lesions between various species. A distinction was made between glomerulonephritis as a primary disease entity and glomerulonephritis associated with other disease processes. Primary idiopathic glomerulonephritis occurred in all species but was most commonly recognized as a clinically important disease in dogs and cats. Glomerulonephritis also occurred in association with other diseases such as equine infectious anemia, chronic hog cholera, canine pyometra, dirofilariasis, feline leukemia virus infection and canine systemic lupus erythematosus. PMID:442447

  13. Obscured AGN

    NASA Astrophysics Data System (ADS)

    Barger, Amy

    2014-07-01

    Obscured AGN may correspond to a substantial fraction of the supermassive black hole growth rate. I will present new surveys with the SCUBA-2 instrument on the James Clerk Maxwell Telescope of the Chandra Deep Fields and discuss whether we can distinguish obscured AGN in hard X-ray and radio selected samples using submillimeter observations.

  14. Membranoproliferative glomerulonephritis with essential cryoglobulinemia

    PubMed Central

    Satish, S.; Rajesh, R.; George, K.; Elango, E. M.; Unni, V. N.

    2008-01-01

    Cryoglobulinemia is an uncommon cause of renal disease and often occurs in patients with hepatitis C virus (HCV) infection. We report a case of membranoproliferative glomerulonephritis in a patient with cryoglobulinemia, which was not associated with HCV infection or any identifiable etiology. PMID:20142909

  15. Staphylococcus-related glomerulonephritis and poststreptococcal glomerulonephritis: why defining "post" is important in understanding and treating infection-related glomerulonephritis.

    PubMed

    Glassock, Richard J; Alvarado, Anthony; Prosek, Jason; Hebert, Courtney; Parikh, Samir; Satoskar, Anjali; Nadasdy, Tibor; Forman, John; Rovin, Brad; Hebert, Lee A

    2015-06-01

    A spate of recent publications describes a newly recognized form of glomerulonephritis associated with active staphylococcal infection. The key kidney biopsy findings, glomerular immunoglobulin A (IgA) deposits dominant or codominant with IgG deposits, resemble those of IgA nephritis. Many authors describe this condition as "postinfectious" and have termed it "poststaphylococcal glomerulonephritis." However, viewed through the prism of poststreptococcal glomerulonephritis, the prefix "post" in poststaphylococcal glomerulonephritis is historically incorrect, illogical, and misleading with regard to choosing therapy. There are numerous reports describing the use of high-dose steroids to treat poststaphylococcal glomerulonephritis. The decision to use steroid therapy suggests that the treating physician believed that the dominant problem was a postinfectious glomerulonephritis, not the infection itself. Unfortunately, steroid therapy in staphylococcus-related glomerulonephritis can precipitate severe staphylococcal sepsis and even death and provides no observable benefits. Poststreptococcal glomerulonephritis is an authentic postinfectious glomerulonephritis; poststaphylococcal glomerulonephritis is not. Making this distinction is important from the perspective of history, pathogenesis, and clinical management. PMID:25890425

  16. Protracted Clinical Course of Postinfectious Glomerulonephritis in a Previously Healthy Child

    PubMed Central

    Grøndahl, Camilla; Rittig, Søren; Povlsen, Johan Vestergaard; Kamperis, Kostantinos

    2016-01-01

    Acute postinfectious glomerulonephritis (PIGN) affects children typically after upper respiratory tract or skin infections with streptococci but can complicate the course of other infections. In children, it is generally a self-limiting disease with excellent prognosis. This paper reports a previously healthy 4-year-old boy who experienced a protracted course of PIGN with persisting episodes of gross haematuria, proteinuria, decreased complement C3c levels but normal P-creatinine levels. Due to the protracted course and the nephrotic-range proteinuria, a renal biopsy was performed 6 months after the initial presentation and the overall pathology was consistent with acute endocapillary glomerulonephritis. PMID:27226969

  17. [Hypertension and primary glomerulonephritis in adults. A study of 302 cases].

    PubMed

    Seba, A; Rayane, T; Kaci, L; Haddoum, F; Benabadji, M

    1997-08-01

    The purpose of the present work was to show the place of hypertension in primary glomerulonephritis in adults. Hypertension was defined as diastolic blood pressure above 90 mmHg and renal insufficiency as serum creatinine above 135 mc mol/L. Secondary glomerulonephritis was excluded. The study was performed in 302 patients with primary glomerulonephritis biopsied between March 1994 and March 1996. They were 183 males and 119 females, aged from 16 to 63 years (mean: 29.8 years). The incidence of hypertension at the time of admission was 46.6%: 141/302 cases. The only consideration of prolonged hypertension (excluded transient hypertension of acute nephritic syndrome) shows an incidence of 31.4%: 95/302 cases (table). Frequency of hypertension (HT) in different types of primary glomerulonephritis (GN): [table: see text] The histological types observed in these cases of hypertension were represented essentially by the proliferative lesions: 73% (72/95 cases) who were grouped mainly in proliferative glomerulonephritis postinfectious and IgA nephropathy. No proliferative lesions: 24% (23/95 cases) were especially represented by focal segmental sclerosis. Renal insufficiency noted in 69 cases on 95 hypertensions was probably the result of the parallel evolution of hypertension renal lesions and those belonging to these histologic types. In conclusion, this study shows a narrow correlation between the hypertension and proliferative glomerulonephritis in our young adults population. PMID:9404432

  18. Haematuria on the Spanish Registry of Glomerulonephritis

    PubMed Central

    Yuste, Claudia; Rivera, Francisco; Moreno, Juan Antonio; López-Gómez, Juan Manuel

    2016-01-01

    Recent studies suggest a pathogenic role for glomerular haematuria among renal function. However, there is no data on the prevalence of haematuria from a large renal biopsy registry. We analysed the prevalence of gross (GH) and microscopic (mH) haematuria in 19,895 patients that underwent native renal biopsies from the Spanish Registry of Glomerulonephritis. Haematuria’s overall incidence was 63% (GH 8.6% and mH 55.1%), being more frequent in males (64.7% vs. 62.4%). GH was more prevalent in patients <18 years (21.3% vs. 7.7%). The commonest clinical presentation associated with GH was acute kidney injury (31.5%) and IgA Nephropathy (IgAN) (33.6%) was the most frequent histological finding. GH patients showed a significantly (p < 0.05) lower eGFR and proteinuria levels as compared with patients with mH and without haematuria. Moreover, mH was more prevalent in adults (56.3%). Nephrotic syndrome was the commonest clinical presentation in mH patients (32.2%) and IgAN (18.5%) the most frequent histological finding. In conclusion, haematuria, is a frequent urinalysis finding in patients underwent native renal biopsy. The most frequent histological finding in both GH and mH is IgAN. Whereas, GH is more frequent in young males with acute kidney injury, mH is commoner among adults with nephrotic syndrome. PMID:26818712

  19. Autoimmune lymphoproliferative syndrome presenting with glomerulonephritis.

    PubMed

    Kanegane, Hirokazu; Vilela, Maria Marluce dos Santos; Wang, Yue; Futatani, Takeshi; Matsukura, Hiroyoshi; Miyawaki, Toshio

    2003-05-01

    Autoimmune lymphoproliferative syndrome (ALPS) is characterized clinically by chronic non-malignant lymphoproliferation and autoimmunity and is caused by a genetic defect in programmed cell death (apoptosis). Most patients with ALPS have heterozygous mutations in the Fas gene. We describe an 11-year-old Brazilian boy with hepatosplenomegaly, lymphadenopathy, hemolytic anemia, and hypergammaglobulinemia since early infancy. T cell lines from the patient were defective in Fas-mediated apoptosis. He was diagnosed as having ALPS and found to have a novel Fas gene mutation (IVS4+1G>A). In addition, he presented with glomerulonephritis in infancy. An aunt and uncle who had the same Fas mutations also had histories of glomerulonephritis. Although glomerulonephritis is common in Fas-deficient mice, it is infrequent in human ALPS. Corticosteroid therapy ameliorated the glomerulonephritis in our patient, as well as his lymphoproliferation, anemia, and hypergammaglobulinemia. This study suggests that glomerulonephritis is one of the characteristic features of ALPS. PMID:12736807

  20. Membranous glomerulonephritis: a morphometric study.

    PubMed

    Paraskevakou, H; Kavantzas, N; Pavlopoulos, P M; Voudiklari, S; Zerefos, N; Papagalanis, N; Davaris, P

    2000-01-01

    Archival material from 45 renal biopsies with a diagnosis of idiopathic membranous glomerulonephritis (MGN) were studied by computer-aided image analysis in order to evaluate the prognostic significance of glomerular and interstitial morphometry in MGN. The control group consisted of thirty seven normal renal biopsy specimens. The surface area, the perimeter, the major axis length and the shape factor of renal glomeruli as well as the percentage of the interstitial fibrosis were measured. All the morphometric parameters related to the size of glomeruli had significantly higher values in the patient group (p = 0.000 for all the parameters). However, no significant difference of the glomerular size between different stages of MGN was observed. In contrast, the percentage of interstitial fibrosis increased as the MGN stage rose (median values: 10.3% in stage 1, 14.2% in stage II, 26.9% in stage III, 28.9% in stage IV and 34.2% in stage V, Kruskal-Wallis ANOVA H = 37.645, p = 0.000). In the multivariate analysis the percentage of interstitial fibrosis was the only independent prognostic factor (p = 0.013). Our findings suggest that, in membraneous glomerulonephritis, the interstitial fibrosis increases as the MGN stage progresses, while the size of renal glomeruli has increased at a very early stage of the disease. This fact may indicate that interstitial fibrosis, not glomerular lesions, is mainly responsible for the reduction of renal function. PMID:10729917

  1. Streptococcal Infection-related Nephritis (SIRN) Manifesting Membranoproliferative Glomerulonephritis Type I.

    PubMed

    Iseri, Ken; Iyoda, Masayuki; Yamamoto, Yasutaka; Kobayashi, Naoto; Oda, Takashi; Yamaguchi, Yutaka; Shibata, Takanori

    2016-01-01

    We herein report the case of an 18-year-old boy who developed nephrotic syndrome and hypertension after upper airway inflammation. Post-streptococcal acute glomerulonephritis was diagnosed on the basis of a high antistreptolysin O titer, hypocomplementemia, proteinuria, and microscopic hematuria. A renal biopsy was performed due to persistent proteinuria, and the pathological diagnosis was membranoproliferative glomerulonephritis (MPGN) type I. Glomeruli showed positive staining for nephritis-associated plasmin receptor (NAPlr), a nephritogenic group A streptococcal antigen, and plasmin activity was found in a similar distribution as NAPlr deposition. This rare case of streptococcal infection-related nephritis (SIRN) manifesting MPGN type I supports the histological diversity of SIRN. PMID:26984084

  2. Glomerulonephritis

    MedlinePlus

    ... seen, including: Nerve inflammation (polyneuropathy) Signs of fluid overload, including abnormal heart and lung sounds Swelling ( edema ) ... to achieve this important distinction for online health information and services. Learn more about A.D.A. ...

  3. Glomerulonephritis associated with arteritis in marmosets infected with hepatitis A virus.

    PubMed Central

    Morita, M.; Kitajima, K.; Yoshizawa, H.; Itoh, Y.; Iwakiri, S.; Shibata, C.; Mayumi, M.

    1981-01-01

    Seven of 8 marmosets (Saguinus oedipus and Saguinus labiatus) injected i.v. with different inocula of hepatitis A virus isolated from patients in the acute phase of disease developed proliferative glomerulonephritis associated with arteritis. The glomerulonephritis was characterized by immunofluorescent and electron-dense deposits and hypercellularity. Although no antigenic component of the glomerular immune complex was detected, this glomerulonephritis and arteritis may be diagnosed morphologically as an immune complex disease. These findings show the possibility of the appearance of exohepatic disease as an immunologically mediated disease in human hepatitis A virus infection. Images Figs. 2-5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Figs. 10-15 Figs. 16-18 PMID:6452891

  4. Gastric Syphilis and Membranous Glomerulonephritis.

    PubMed

    Roh, Min; Sohn, Joo Hyun; Kim, Tae Yeob; Kim, Sung Jong; Kim, Ji Soong; Chung, Sung Jun; Pyo, Ju Yeon; Oh, Young-Ha

    2015-05-01

    Syphilis is a chronic systemic infectious disease caused by the bacterium Treponema pallidum. Gastric involvement and nephrotic syndrome are uncommon but well documented complications of syphilis, but the co-occurrence of these two complications in the same patient is extremely rare. Thus, because of their nonspecific presentation, suspicion of gastric syphilis (GS) and nephrotic syndrome is essential for diagnosis. Patients should be investigated thoroughly and a diagnosis made based on clinical, endoscopic, and histological findings, in order to initiate appropriate therapy. We report of a 34-year-old male patient with a history of epigastric pain and a diagnosis of GS and syphilis-associated membranous glomerulonephritis confirmed by gastroscopy and kidney biopsy, who was treated successfully with penicillin G benzathine. This case report provides information on the typical features of GS that should help raise awareness of this rare disease entity among clinicians, resulting in earlier diagnosis and administration of appropriate therapy. PMID:26064828

  5. Gastric Syphilis and Membranous Glomerulonephritis

    PubMed Central

    Roh, Min; Kim, Tae Yeob; Kim, Sung Jong; Kim, Ji Soong; Chung, Sung Jun; Pyo, Ju Yeon; Oh, Young-Ha

    2015-01-01

    Syphilis is a chronic systemic infectious disease caused by the bacterium Treponema pallidum. Gastric involvement and nephrotic syndrome are uncommon but well documented complications of syphilis, but the co-occurrence of these two complications in the same patient is extremely rare. Thus, because of their nonspecific presentation, suspicion of gastric syphilis (GS) and nephrotic syndrome is essential for diagnosis. Patients should be investigated thoroughly and a diagnosis made based on clinical, endoscopic, and histological findings, in order to initiate appropriate therapy. We report of a 34-year-old male patient with a history of epigastric pain and a diagnosis of GS and syphilis-associated membranous glomerulonephritis confirmed by gastroscopy and kidney biopsy, who was treated successfully with penicillin G benzathine. This case report provides information on the typical features of GS that should help raise awareness of this rare disease entity among clinicians, resulting in earlier diagnosis and administration of appropriate therapy. PMID:26064828

  6. Crescentic Glomerulonephritis Associated with Pulmonary Tuberculosis

    PubMed Central

    Vanikar, A.V.; Patel, R.D.; Suthar, K. S.; Trivedi, H. L.

    2016-01-01

    Tuberculosis of kidney and urinary tract is caused by members of the Mycobacterium tuberculosis complex. Kidney is usually infected by haematogenous spread of bacilli from focus of infection in the lungs. Glomerular involvement in tuberculosis presenting as a rapidly progressive glomerulonephritis is a rare entity. We report a rare case of crescentic glomerulonephritis associated with pulmonary tuberculosis in a 26-year-old man. Patient was treated with corticosteroids, haemodialysis, intravenous immunoglobulin and four cycles of plasmapheresis. He did not respond to 4-drug anti-tuberculosis treatment for renal pathology and was switched over to maintenance haemodialysis. However, he responded to pulmonary TB. PMID:26894074

  7. Monoclonal immunoglobulin G1-kappa fibrillary glomerulonephritis.

    PubMed

    Grove, P; Neale, P H; Peck, M; Schiller, B; Haas, M

    1998-01-01

    We report here a case of fibrillary glomerulonephritis arising in a 43-year-old man with a polyclonal gammopathy, who presented with progressive renal insufficiency, microscopic hematuria, and mild proteinuria (0.7 g/d). Ultrastructural studies showed deposits of randomly oriented fibrils in the glomerular mesangium and adjacent portions of some glomerular basement membranes, with a mean fibril thickness of 14.3 nm, highly consistent with fibrillary glomerulonephritis. The Congo red stain was negative on histologic sections. Immunofluorescence studies revealed strong mesangial and focal glomerular capillary staining for immunoglobulin (Ig) G, complement (C) 3, and kappa light chains, with minimal staining for IgA, IgM, C1q, or lambda light chains. The IgG present was entirely of the IgG1 subclass. This case is quite unusual for fibrillary glomerulonephritis, which typically presents with polyclonal IgG deposits and IgG4 as the dominant IgG subclass present. Monoclonal deposits are more frequently associated with immunotactoid glomerulopathy, characterized ultrastructurally by microtubule-like structures 30 to 50 nmn thick, often in parallel arrays. The present case illustrates that although fibrillary glomerulonephritis and immunotactoid glomerulopathy might be distinguishable on ultrastructural grounds, there is overlap between these two entities with respect to the potential composition of the glomerular deposits present. PMID:9556416

  8. Clinical, Pathological, and Prognostic Characteristics of Glomerulonephritis Related to Staphylococcal Infection

    PubMed Central

    Wang, Si-Yang; Bu, Ru; Zhang, Qi; Liang, Shuang; Wu, Jie; Liu, Xue-Guang Zhang Shu-Wen; Cai, Guang-Yan; Chen, Xiang-Mei

    2016-01-01

    Abstract Staphylococcal infection has become a common cause of postinfectious glomerulonephritis in the past 3 decades. Because few investigations focus on this disease, the demographics and clinicopathological features of glomerulonephritis related to staphylococcal infection are not well characterized. We conducted a pooled analysis of published literature in electronic databases and analyzed the clinical features, laboratory findings, and histopathological changes. The patients were divided into 4 groups based on their prognosis: remission, persistent renal dysfunction, end-stage renal disease (ESRD), or death. A logistic regression model was used to identify the determinants of disease outcome. A total of 83 (64 men) patients with glomerulonephritis related to staphylococcal infection from 31 reports were analyzed. The mean age was 58 years (58 ± 17). Majority of the reports originated from Taiwan, Japan, and the United States. Clinical characteristics of the cases were hematuria (82/83), proteinuria (78/83), and acute kidney injury (75/83). Visceral abscesses (26/83) and skin infections (24/83) were the common sites of infection. Methicillin-resistant Staphylococcus aureus was the most common pathogen. The dominant or codominant deposition of IgA or C3 along the glomeruli was an important feature identified by immunofluorescence. There were 19 patients (22.9%) that progressed to dialysis-dependent ESRD. Twelve patients (14.5%) died. A univariate regression analysis indicated that diabetes mellitus (DM) (odds ratio [OR] 2.96; 95% confidence interval [CI] 1.03–8.48; P = 0.04) and age (OR 4.80; 95% CI 1.84–12.53; P = 0.001) were risk factors for ESRD or death. A multivariate regression analysis also revealed that age (OR 4.90; 95% CI 1.82–13.18; P = 0.002) and DM (OR 3.07; 95% CI 0.98–9.59; P = 0.05) were independent risk factors for unfavorable prognosis. Glomerulonephritis related to staphylococcal infection has different features

  9. Clinical, Pathological, and Prognostic Characteristics of Glomerulonephritis Related to Staphylococcal Infection.

    PubMed

    Wang, Si-Yang; Bu, Ru; Zhang, Qi; Liang, Shuang; Wu, Jie; Liu, Xue-Guang Zhang Shu-Wen; Cai, Guang-Yan; Chen, Xiang-Mei

    2016-04-01

    Staphylococcal infection has become a common cause of postinfectious glomerulonephritis in the past 3 decades. Because few investigations focus on this disease, the demographics and clinicopathological features of glomerulonephritis related to staphylococcal infection are not well characterized.We conducted a pooled analysis of published literature in electronic databases and analyzed the clinical features, laboratory findings, and histopathological changes. The patients were divided into 4 groups based on their prognosis: remission, persistent renal dysfunction, end-stage renal disease (ESRD), or death. A logistic regression model was used to identify the determinants of disease outcome.A total of 83 (64 men) patients with glomerulonephritis related to staphylococcal infection from 31 reports were analyzed. The mean age was 58 years (58 ± 17). Majority of the reports originated from Taiwan, Japan, and the United States. Clinical characteristics of the cases were hematuria (82/83), proteinuria (78/83), and acute kidney injury (75/83). Visceral abscesses (26/83) and skin infections (24/83) were the common sites of infection. Methicillin-resistant Staphylococcus aureus was the most common pathogen. The dominant or codominant deposition of IgA or C3 along the glomeruli was an important feature identified by immunofluorescence. There were 19 patients (22.9%) that progressed to dialysis-dependent ESRD. Twelve patients (14.5%) died. A univariate regression analysis indicated that diabetes mellitus (DM) (odds ratio [OR] 2.96; 95% confidence interval [CI] 1.03-8.48; P = 0.04) and age (OR 4.80; 95% CI 1.84-12.53; P = 0.001) were risk factors for ESRD or death. A multivariate regression analysis also revealed that age (OR 4.90; 95% CI 1.82-13.18; P = 0.002) and DM (OR 3.07; 95% CI 0.98-9.59; P = 0.05) were independent risk factors for unfavorable prognosis.Glomerulonephritis related to staphylococcal infection has different features than typical

  10. Noncongophilic fibrillary glomerulonephritis in a cat.

    PubMed

    Cavana, P; Capucchio, M T; Bovero, A; Ripanti, D; Catalano, D; Scaglione, F E; Miller, J; Blunden, T; Farca, A M

    2008-05-01

    This report describes an uncommon case of nonamyloidotic fibrillary glomerulonephritis. A 5-year-old female European cat was presented with nephrotic syndrome. Serum biochemistry and urinalysis revealed a mild increase in cholesterol, low total protein, severe hypoalbuminemia, and high proteinuria with a high protein-to-creatinine ratio. An histologic examination revealed an interstitial nephritis and a diffuse glomerulonephritis, with multifocal thickening of the Bowman's capsule. Transmission electron microscopy showed widespread fibrillary deposits in the glomerular basement membrane and in the mesangium. These fibrils ranged between 18 and 26 nm in diameter and were Congo red negative, which allowed their differentiation from amyloid. Immunohistochemistry demonstrated expression for immunoglobulin M (IgM) and immunoglobulin G (IgG) within the mesangium. Renal deposits of Congo red-negative amyloid-like fibrils have been described in humans, horses, monkeys, and dogs. This is the first report of noncongophilic fibrillary glomerulopathy in a cat. PMID:18487491

  11. Atypical membranoproliferative glomerulonephritis in a cat.

    PubMed

    Inoue, K; Kami-ie, J; Ohtake, S; Wakui, S; Machida, S; Shirota, K

    2001-07-01

    Membranoproliferative glomerulonephritis was observed in a 2-year-old male Japanese domestic cat with clinical renal failure. In the glomeruli, moderate mesangial hypercellularity with an increased mesangial matrix and thickening of the capillary walls were prominent. In addition, frequent duplication of the capillary walls, splitting, and spike formation were observed in the glomerular basement membrane. Granular cat IgG and complement component deposition were detected globally along the glomerular capillary walls and in the mesangium. Transmission electron microscopy revealed dense deposits in the subendothelial and subepithelial regions and the mesangium. Mesangial interposition was also observed. These glomerular lesions are also found in humans with membranoproliferative glomerulonephritis type III, which has not been reported in animals. PMID:11467485

  12. Forty years abuse of baking soda, rhabdomyolysis, glomerulonephritis, hypertension leading to renal failure: a case report.

    PubMed

    Forslund, Terje; Koistinen, Arvo; Anttinen, Jorma; Wagner, Bodo; Miettinen, Marja

    2008-01-01

    We present a patient who had ingested sodium bicarbonate for treatment of alcoholic dyspepsia during forty years at increasing doses. During the last year he had used more than 50 grams daily. He presented with metabolic alkalosis, epileptic convulsions, subdural hematoma, hypertension and rhabdomyolysis with end stage renal failure, for which he had to be given regular intermittent hemodialysis treatment. Untreated hypertension and glomerulonephritis was probably present prior to all these acute incidents. Examination of the kidney biopsy revealed mesangial proliferative glomerulonephritis and arterial wall thickening causing nephrosclerosis together with interstitial calcinosis. The combination of all these pathologic changes might be responsible for the development of progressive chronic renal failure ending up with the need for continuous intermittent hemodialysis treatment. PMID:24179353

  13. Signatures of AGN feedback

    NASA Astrophysics Data System (ADS)

    Wylezalek, D.; Zakamska, N.

    2016-06-01

    Feedback from active galactic nuclei (AGN) is widely considered to be the main driver in regulating the growth of massive galaxies. It operates by either heating or driving the gas that would otherwise be available for star formation out of the galaxy, preventing further increase in stellar mass. Observational proof for this scenario has, however, been hard to come by. We have assembled a large sample of 133 radio-quiet type-2 and red AGN at 0.1AGN-ionized gas, the stellar masses of the host galaxies and their star formation rates. We then investigate the relationships between AGN luminosities, specific star formation rates (sSFR) and outflow strengths W_{90} - the 90% velocity width of the [OIII]λ5007Å line power and a proxy for the AGN-driven outflow speed. Outflow strength W_{90} is independent of sSFR for AGN selected based on their mid-IR luminosity. This is in agreement with previous work that demonstrates that star formation is not sufficient to produce the observed ionized gas outflows which have to be powered by AGN activity. More importantly, we find a negative correlation between W_{90} and sSFR in the AGN hosts with the highest star formation rates, i.e., with the highest gas content. This relationship implies that AGN with strong outflow signatures are hosted in galaxies that are more `quenched' considering their stellar mass than galaxies with weaker outflow signatures. This correlation is only seen in AGN host galaxies with SFR >100 M_{⊙} yr^{-1} where presumably the coupling of the AGN-driven wind to the gas is strongest. This observation is consistent with the AGN having a net suppression, or `negative' impact, through feedback on the galaxies' star formation history.

  14. Nephrotic Syndrome without Hematuria due to Infection-Related Glomerulonephritis Mimicking Minimal-Change Disease in a Child.

    PubMed

    Iwafuchi, Yoichi; Morioka, Tetsuo; Morita, Takashi; Watanabe, Kanako; Oyama, Yuko; Narita, Ichiei

    2016-01-01

    Nephrotic syndrome without hematuria due to infection-related glomerulonephritis is uncommon. The present report describes a case of nephrotic syndrome due to infection-related glomerulonephritis without hematuria and hypertension in an older child. A 14-year-old boy was referred to our hospital because of a 5-day history of fever, nausea, weight gain and recent leg edema without hypertension. Laboratory data showed nephrotic-range proteinuria, hypoalbuminemia, mild hypocomplementemia and acute renal injury without hematuria. Although, due to the clinical presentation, minimal-change nephrotic syndrome was mostly suspected, a renal biopsy showed endocapillary hypercellularity mainly of mononuclear cells with segmental mesangiolytic changes. Fine granular IgG and C3 deposits were noted by an immunofluorescent study; many relatively small electron-dense deposits were observed electron-microscopically. These findings led to the diagnosis of nephrotic syndrome due to infection-related endocapillary proliferative glomerulonephritis, although the causative organism of his nephritis was not detected. He recovered with rest and dietary cure. When we examine an acute nephrotic child, infection-related glomerulonephritis should be considered as the differential diagnosis to avoid unnecessary use of corticosteroids. PMID:26889476

  15. A protective role for endothelial nitric oxide synthase in glomerulonephritis.

    PubMed

    Heeringa, Peter; Steenbergen, Eric; van Goor, Harry

    2002-03-01

    In acute glomerulonephritis (GN), increased nitric oxide (NO) production occurs, suggesting a pathophysiological role for NO in the disease process. Although NO potentially could have both toxic as well as protective effects, its exact role in the pathophysiology of GN is unclear and may depend on the NOS isoform generating NO. The protective effects of NO such as prevention of leukocyte and platelet activation and adhesion have been attributed to NO generated by endothelial nitric oxide synthase (eNOS). Evidence for a beneficial role for eNOS includes the demonstration of reduced eNOS expression in experimental models of GN as well as human biopsy specimens that is mostly likely due to endothelial cell necrosis. Reduced NO production in GN also may occur through reaction of NO with superoxide anions or the myeloperoxidase (MPO)/hypochlorous acid (HOCL) system. Further evidence has been provided by the observation that in several experimental models of GN, glomerular injury is exacerbated following treatment with non-selective NO inhibitors. Finally, the development of GN is severely aggravated in mice lacking a functional gene for eNOS as compared to wild-type mice, providing direct support for a protective role of eNOS-derived NO in acute GN. PMID:11849432

  16. Post-infectious glomerulonephritis following infective endocarditis: Amenable to immunosuppression

    PubMed Central

    Mantan, M.; Sethi, G. R.; Batra, V. V.

    2013-01-01

    Glomerulonephritis develops in about 20% patients with infective endocarditis (IE), but is mostly asymptomatic. Heavy proteinuria or derangement of kidney functions is uncommon. We report here a child with IE and proliferative glomerulonephritis who manifested as significant proteinuria that recovered on treatment with immunosupressants. PMID:24049276

  17. Conditional Deletion of Smad1 Ameliorates Glomerular Injury in Progressive Glomerulonephritis

    PubMed Central

    Araki, Makoto; Matsubara, Takeshi; Abe, Hideharu; Torikoshi, Kazuo; Mima, Akira; Iehara, Noriyuki; Fukatsu, Atsushi; Kita, Toru; Arai, Hidenori; Doi, Toshio

    2016-01-01

    Matrix expansion and cell proliferation are concomitantly observed in various glomerular injuries. However, the molecular mechanisms responsible for these changes have not been fully elucidated. We have reported that Smad1 is a key signalling molecule that regulates the transcription of type IV collagen (Col4) in mesangial matrix expansion and is thereby involved in glomerular injury in an acute model of glomerulonephritis. In this study, we addressed the role of Smad1 signalling in accelerated nephrotoxic nephritis (NTN), a model of progressive glomerulonephritis, using conditional deletion of Smad1 in Rosa26CreERT2 mice (Smad1-CKO). Mesangial matrix expansion in the Smad1-CKO mice with NTN was significantly inhibited compared with that in wild type mice with NTN, which was consistent with the decrease in Col4 expression level. On the other hand, STAT3 activation and cell proliferation were not influenced by Smad1 deletion in the NTN model. Therefore, we investigated another factor that activates cell proliferation in the absence of Smad1. Id2 induced VEGF secretion and subsequent STAT3 activation, independently of Smad1 expression in mouse mesangial cells. Here we show that Smad1 plays an important role in the development of glomerular injury without affecting cell proliferation, in progressive glomerulonephritis. PMID:27492138

  18. Conditional Deletion of Smad1 Ameliorates Glomerular Injury in Progressive Glomerulonephritis.

    PubMed

    Araki, Makoto; Matsubara, Takeshi; Abe, Hideharu; Torikoshi, Kazuo; Mima, Akira; Iehara, Noriyuki; Fukatsu, Atsushi; Kita, Toru; Arai, Hidenori; Doi, Toshio

    2016-01-01

    Matrix expansion and cell proliferation are concomitantly observed in various glomerular injuries. However, the molecular mechanisms responsible for these changes have not been fully elucidated. We have reported that Smad1 is a key signalling molecule that regulates the transcription of type IV collagen (Col4) in mesangial matrix expansion and is thereby involved in glomerular injury in an acute model of glomerulonephritis. In this study, we addressed the role of Smad1 signalling in accelerated nephrotoxic nephritis (NTN), a model of progressive glomerulonephritis, using conditional deletion of Smad1 in Rosa26CreERT2 mice (Smad1-CKO). Mesangial matrix expansion in the Smad1-CKO mice with NTN was significantly inhibited compared with that in wild type mice with NTN, which was consistent with the decrease in Col4 expression level. On the other hand, STAT3 activation and cell proliferation were not influenced by Smad1 deletion in the NTN model. Therefore, we investigated another factor that activates cell proliferation in the absence of Smad1. Id2 induced VEGF secretion and subsequent STAT3 activation, independently of Smad1 expression in mouse mesangial cells. Here we show that Smad1 plays an important role in the development of glomerular injury without affecting cell proliferation, in progressive glomerulonephritis. PMID:27492138

  19. Neutrinos from AGN

    NASA Technical Reports Server (NTRS)

    Kazanas, Demosthenes; White, Nicholas E. (Technical Monitor)

    2000-01-01

    The great penetrating power of neutrinos makes them ideal probe of astrophysical sites and conditions inaccessible to other forms of radiation. These are the centers of stars (collapsing or not) and the centers of Active Galactic Nuclei (AGN). It has been suggested that AGN presented a very promising source of high energy neutrinos, possibly detectable by underwater neutrino detectors. This paper reviews the evolution of ideas concerning the emission of neutrinos from AGN in view of the more recent developments in gamma-ray astronomy and their implications for the neutrino emission from these class of objects.

  20. Membranoproliferative glomerulonephritis with masked monotypic immunoglobulin deposits

    PubMed Central

    Larsen, Christopher P; Messias, Nidia C; Walker, Patrick D; Fidler, Mary E; Cornell, Lynn D; Hernandez, Loren H; Alexander, Mariam P; Sethi, Sanjeev; Nasr, Samih H

    2015-01-01

    The diagnosis of membranoproliferative glomerulonephritis (MPGN) has recently undergone change from an electron microscopy-based classification scheme to one based largely on immunofluorescence findings. This change is due to the recognition that many of these cases are driven by abnormalities of the alternative complement cascade, resulting in the concept of C3 glomerulopathy. Here we reviewed our case files to identify those with an MPGN pattern that show false negative staining for monoclonal immunoglobulins by routine immunofluorescence. Monoclonal immunoglobulin deposits were unmasked by performing immunofluorescence on formalin-fixed paraffin embedded tissue after protease digestion. Clinico-pathological details of 16 such cases with a mean serum creatinine of 2.7 mg/dl and mean 24 h proteinuria of 7.1 g were then determined. Hypocomplementemia was present in two-thirds of patients. Fourteen patients had a paraprotein on serum immunofixation, all of which matched the biopsy immunofluorescence staining pattern. Bone marrow biopsy showed plasma cell dyscrasia or B-cell lymphoproliferative disorder in 13 patients. Ten of these patients had findings on biopsy most consistent with C3 glomerulonephritis prior to performing paraffin immunofluorescence. Thus a high index of suspicion is necessary to avoid misdiagnosis in these cases, as many would have been mistakenly diagnosed as C3 glomerulopathy or unclassified MPGN if paraffin immunofluorescence was not performed. PMID:26154922

  1. [Immune complex glomerulonephritis associated with pulmonary tuberculosis].

    PubMed

    Villar, I; Hernández, E; Cozzi, J; Paletta, C; Mathurín, S

    1994-01-01

    A 32 year old man was admitted for dyspnea, hemoptysis, macroscopic hematuria, hypertension (140/100), peripheral edema and hemodynamic decompensation. Lung Xrays revealed pulmonary edema and a cavity in the left apex. Laboratory determinations revealed an altered renal function with increased creatinine and urea levels and nephrotic syndrome. There was leucocyturia, hematuria and cylindruria. The sputum showed a large number of acid-fast bacilli. The patient began anti-tuberculosis treatment with three drugs (isoniacid, rifampicin, pirazinamide). On ultrasonography, both kidneys revealed ecogenic lesions with size, shape and cortico-medular relationship preserved. The patient persisted with altered renal function, steady levels of urea nitrogen, creatinine and potassium, preserved diuresis and hypertension. Bidimensional echocardiogram: LVDD 55 mm, hypoquinetic septum, pericardic effusion, thickened pericardium, pleural effusion, shortening fraction decreased. He received treatment for this congestive cardiac failure and hypertension with enalapril, nifedipine and fursemide. A percutaneous renal biopsy was performed with anatomopathologic diagnosis of diffuse encocapillar proliferative glomerulonephritis with crescents (15%) and total glomerular sclerosis (33%). Immunofluorescence: positive, immune-complexes with IgM and C3. The patient gradually recovered his normal renal function, improved his pleural effusions and normalized his cardiac function. He was discharged in good clinical condition on the 69th day of anti-tuberculosis treatment. An association between pulmonary tuberculosis and glomerulonephritis is discussed. It is proposed that renal lesions might be the consequence of the tuberculosis due to the sedimentation of circulating immune-complexes. PMID:7854090

  2. Fibrillary glomerulonephritis masquerading as rapidly progressive glomerulonephritis with pseudo-linear glomerular basement membrane staining.

    PubMed

    El-Husseini, Amr; Aycinena, Juan-Carlos; George, Bennet; Jennings, Stuart; Cornea, Virgilius; Sawaya, B Peter

    2015-10-01

    Fibrillary glomerulonephritis (FGN) is a rare disorder with poor renal prognosis. It is a heterogeneous disease associated with significant risk of end-stage renal disease (ESRD). Its etiology and pathogenesis have not been clearly identified. We report a case of a patient presenting with hypertensive crisis, nephrotic range proteinuria, and rapidly progressive glomerulonephritis (RPGN). The kidney biopsy demonstrates crescentic GN on light microscopy (LM) and strong pseudo-linear/globular glomerular basement membrane (GBM) staining for immunoglobulin G on immunofluorescence (IF), suggestive of anti-GBM disease. However, circulating anti-GBM antibodies were negative. Electron microscopy (EM) revealed fibrillary deposits in the GBM, confirming the diagnosis of FGN. Review of the literature revealed very few reported similar cases. It appears that severe hypertension and heavy proteinuria, while uncommon in anti-GBM disease, are consistent findings in RPGN form of FGN. PMID:26249548

  3. Rapidly progressive glomerulonephritis due to coexistent anti-glomerular basement membrane disease and fibrillary glomerulonephritis

    PubMed Central

    Cheungpasitporn, Wisit; Zacharek, Claudia C.; Fervenza, Fernando C.; Cornell, Lynn D.; Sethi, Sanjeev; Herrera Hernandez, Loren P.; Nasr, Samih H.; Alexander, Mariam P.

    2016-01-01

    Anti-glomerular basement membrane (anti-GBM) disease is a major cause of rapidly progressive glomerulonephritis (RPGN). On the other hand, fibrillary glomerulonephritis (GN) typically presents as proteinuria, hematuria and renal insufficiency, but rarely as RPGN. Without electron microscopy, the diagnosis of fibrillary GN can be missed. We report a 68-year-old white woman who presented with RPGN with kidney biopsy demonstrating diffuse crescentic GN on light microscopy. By immunofluorescence, there was bright linear staining of the GBMs and smudgy mesangial staining for immunoglobulin G, C3, and kappa and lambda light chain. Electron microscopy revealed fibrillary deposits in the GBM and mesangium. A serum test for anti-GBM antibody was positive. To our knowledge, this is the first report of coexistence of fibrillary GN in a patient with anti-GBM disease. Electron microscopy is critical to identify the coexistence of other GN in patients presenting with crescentic GN. PMID:26798468

  4. De novo C3 glomerulonephritis in a renal allograft.

    PubMed

    Nahm, Ji Hae; Song, Seung Hwan; Kim, Yu Seun; Cheong, Hae-Il; Lim, Beom Jin; Kim, Beom Seok; Jeong, Hyeon Joo

    2016-01-01

    C3 glomerulonephritis (C3GN) is a recently described, rare glomerular disease characterized by predominant or sole glomerular C3 deposits. Morphologic features of C3GN are similar to those of dense deposit disease (DDD); however, ribbon-like intramembranous electron-dense deposits are absent in the former. We report a case of de novo C3GN in a renal allograft with morphologic transformation to DDD. A 6-year-old boy presented with congenital left renal agenesis and right ureteropelvic junction obstruction. The patient underwent pyeloplasty but experienced recurrent urinary tract infections. At the age of 22 years, he received a renal allograft from a living related donor. C3GN was diagnosed after 1 year of transplantation; initial histology showed minimal mesangiopathy and this progressed to mesangial proliferation and membranoproliferative features over the next 7 years. Serum creatinine levels were stabilized with anti-rejection treatments for combating repeated episodes of acute rejection; however, glomerular and tubular band-like electron-dense deposits became evident. PMID:26986539

  5. Membranoproliferative glomerulonephritis in a young cat.

    PubMed

    Asano, Tomoko; Tsukamoto, Atsushi; Ohno, Koichi; Ogihara, Kikumi; Kamiie, Junichi; Shirota, Kinji

    2008-12-01

    A 9-month-old male Japanese domestic cat showed pleural effusion, ascites, azotemia, hypoproteinemia and severe proteinuria. Histopathology of the percutaneous renal biopsy specimen revealed that all glomeruli showed intense mesangial hypercellularity with an increased mesangial matrix and thickening of the capillary walls, resulting in lobular accentuation of the glomerular tufts. Frequent duplication of the capillary walls was also observed. Immunostaining for alpha-smooth muscle actin distinctly revealed mesangial interposition. Diffuse global and linear deposition of C3 and IgG was observed mostly along the peripheral capillary loops. Electron microscopy confirmed frequent circumferential mesangial interposition and subendothelial dense-deposits in the glomerulus. The glomerular lesion was consistent with human membranoproliferative glomerulonephritis type I, and might be a rare case that developed at young age. PMID:19122409

  6. Experimental proliferative glomerulonephritis in the cat.

    PubMed

    Bishop, S A; Stokes, C R; Lucke, V M

    1992-01-01

    A model of chronic serum sickness was used to induce immune-complex glomerulonephritis in seven experimental cats, by daily intravenous inoculation of an increasing dose (5 to 35 mg) of human serum albumin (HSA). At week four, two of the seven animals developed anterior uveitis. At week 23, two different animals developed the subcutaneous oedema characteristic of the nephrotic syndrome (NS), whilst the other five cats appeared clinically normal. The kidneys were examined at necropsy by light microscopy and by transmission electron microscopy. The glomeruli of four animals (three with both proteinuria and uraemia, and one with proteinuria only) showed morphological changes under light microscopy. The abnormalities suggested that a diffuse mesangial proliferative glomerulonephritis (GN) had been induced in three cats and diffuse membranoproliferative GN induced in another. Ultrastructural studies revealed electron-dense deposits (immune-complexes) in six of the seven cats. Two cats without glomerular abnormalities by light microscopy had mesangial deposits and three cats with mesangial proliferative GN had deposits at mesangial, subendothelial and/or subepithelial sites. The single cat with membranoproliferative GN had deposits at mesangial, subendothelial, subepithelial and intramembranous sites. Immunohistological examination (peroxidase-antiperoxidase technique) showed that HSA and immunoglobulin (IgG and IgM) were deposited in the glomeruli of these cats. Deposits were the most dense in cats with more severe renal lesions. Deposits of IgM were most abundant. An extensive cellular infiltrate, comprising macrophages, neutrophils and plasma cells, was observed only in the four animals which showed abnormalities in glomerular ultrastructure. The disease induced in these cats thus appears to differ from the membranous nephropathy previously described in the cat and bears a close resemblance to immune complex (IC) disease in man. In view of the relatively few specific

  7. Membranous glomerulonephritis associated with Mycobacterium shimoidei pulmonary infection

    PubMed Central

    Kanaji, Nobuhiro; Kushida, Yoshio; Bandoh, Shuji; Ishii, Tomoya; Haba, Reiji; Tadokoro, Akira; Watanabe, Naoki; Takahama, Takayuki; Kita, Nobuyuki; Dobashi, Hiroaki; Matsunaga, Takuya

    2013-01-01

    Patient: Male, 83 Final Diagnosis: Membranous glomerulonephritis Symptoms: Producting cough Medication: — Clinical Procedure: — Specialty: Nephrology Objective: Rare disease Background: Membranous glomerulonephritis can occur secondarily from infectious diseases. There are no reports describing membranous glomerulonephritis caused by non-tuberculous mycobacterium infection. However, several cases with membranous glomerulonephritis due to Mycobacterium tuberculosis have been reported. Mycobacterium shimoidei is an uncommon pathogen, and less than 20 cases with this species have been reported. A therapeutic regimen for this infection has not been established yet. Case Report: An 83-year-old Japanese man presented with productive cough for 6 months. Computed tomography scan showed multiple cavities in the bilateral pulmonary fields. Acid-fast bacilli were evident in his sputum by Ziehl-Neelsen staining (Gaffky 3). PCR amplifications for Mycobacterium tuberculosis, Mycobacterium avium, and Mycobacterium intracellulare were all negative. Finally, Mycobacterium shimoidei was identified by rpoB sequencing and 16S rRNA sequencing. Urine examination showed a sub-nephrotic range of proteinuria and histology of the kidney showed membranous glomerulonephritis. Antimycobacterial treatment with clarithromycin, rifampicin, and ethambutol dramatically improved not only the pulmonary disease, but also the proteinuria. Conclusions: To the best of our knowledge, the presented case is the first report showing non-tuberculous mycobacterium-induced secondary membranous glomerulonephritis. A combination with clarithromycin, ethambutol, and rifampicin might be effective for treatment of Mycobacterium shimoidei infection. PMID:24367720

  8. Murine Double Minute-2 Inhibition Ameliorates Established Crescentic Glomerulonephritis.

    PubMed

    Mulay, Shrikant R; Romoli, Simone; Desai, Jyaysi; Honarpisheh, Mohammad Mohsen; Kumar, Santhosh V; Anders, Hans-Joachim; Thomasova, Dana

    2016-06-01

    Rapidly progressive glomerulonephritis is characterized by glomerular necroinflammation and crescent formation. Its treatment includes unspecific and toxic agents; therefore, the identification of novel therapeutic targets is required. The E3-ubiquitin ligase murine double minute (MDM)-2 is a nonredundant element of NF-κB signaling and the negative regulator of tumor suppressor gene TP53-mediated cell cycle arrest and cell death. We hypothesized that the MDM2 would drive crescentic glomerulonephritis by NF-κB-dependent glomerular inflammation and by p53-dependent parietal epithelial cell hyperproliferation. Indeed, the pre-emptive MDM2 blockade by nutlin-3a ameliorated all aspects of crescentic glomerulonephritis. MDM2 inhibition had identical protective effects in Trp53-deficient mice, with the exception of crescent formation, which was not influenced by nutlin-3a treatment. In vitro experiments confirmed the contribution of MDM2 for induction of NF-κB-dependent cytokines in murine glomerular endothelial cells and for p53-dependent parietal epithelial cell proliferation. To evaluate MDM2 blockade as a potential therapeutic intervention in rapidly progressive glomerulonephritis, we treated mice with established glomerulonephritis with nutlin-3a. Delayed onset of nutlin-3a treatment was equally protective as the pre-emptive treatment in abrogating crescentic glomerulonephritis. Together, the pathogenic effects of MDM2 are twofold, that is, p53-independent NF-κB activation increasing intraglomerular inflammation and p53-dependent parietal epithelial cell hyperplasia and crescent formation. We therefore propose MDM2 blockade as a potential novel therapeutic strategy in rapidly progressive glomerulonephritis. PMID:27102769

  9. SWIFT Observations AGN

    NASA Technical Reports Server (NTRS)

    Mushotzky, Richard

    2008-01-01

    I will present results from the x-ray and optical follow-up observations of the Swift Burst Alert Telescope (BAT) Active Galactic Nuclei (AGN) survey. I will discuss the nature of obscuration in these objects, the relationship to optical properties and the change of properties with luminosity and galaxy type.

  10. Treatment of experimental mesangioproliferative glomerulonephritis with non-anticoagulant heparin: therapeutic efficacy and safety.

    PubMed

    Burg, M; Ostendorf, T; Mooney, A; Koch, K M; Floege, J

    1997-04-01

    Treatment with conventional heparin is effective in experimental mesangioproliferative glomerulonephritis. However, the long-term effects and safety of this therapy, in particular in the presence of mesangiolysis, have not been assessed. In addition, this therapy has been hampered by bleeding complications. In the present study, therefore, we investigated the long-term effects of a short course of non-anticoagulant (NA) heparin treatment in the anti-Thy 1.1 mesangioproliferative glomerulonephritis, in which early immune-mediated mesangiolysis subsequently leads to mesangial hyperproliferation. Rats received continuous ip NA-heparin or vehicle during the active mesangioproliferative phase (Days 2 to 9; early treatment) or during the early resolution phase (Days 10 to 17; late treatment). Whereas NA-heparin in the early treatment group did not affect the glomerular macrophage, lymphocyte, or platelet influx, it did lead to significantly decreased glomerular cellularity, mesangial cell proliferation, alpha-smooth muscle actin, desmin expression (ie, markers of activated mesangial cells), and matrix accumulation as well as to persistent mesangiolytic lesions including microaneurysms. Despite this latter finding, at Day 120, NA-heparin-treated rats of the early treatment group showed significantly better renal function and less proteinuria and glomerulosclerosis than vehicle-infused rats. In contrast, late therapy with NA-heparin neither accelerated resolution of the nephritis or otherwise affected the course of the disease. We conclude that transient NA-heparin therapy is effective in mesangioproliferative glomerulonephritis, both acutely and long term, when it is initiated during the active phase of the disease. Also, NA-heparin therapy is safe even in glomerular diseases accompanied by mesangiolysis. PMID:9111513

  11. Eculizumab and Recurrent C3 Glomerulonephritis

    PubMed Central

    Gurkan, Sevgi; Fyfe, Billie; Weiss, Lynne; Xiao, Xue; Zhang, Yuzhou; Smith, Richard J.

    2015-01-01

    Background and objectives Hyperactivity of the alternative complement pathway is the principle defect in the C3 glomerulopathies (C3G). Eculizumab, a monoclonal antibody that binds to C5 to prevent formation of the membrane attack complex, has been shown to be beneficial in some patients with this disease. Design, setting, participants & measurements In this open-label, proof-of-concept efficacy-and-safety study, a patient with the initial diagnosis of Dense Deposit Disease (DDD) and allograft recurrence of C3 (C3GN) glomerulonephritis was treated with eculizumab every-other-week for 1 year. The patient had pathological evidence of C3GN and proteinuria >1 g/d at enrollment. He underwent graft biopsy before enrollment and repeat biopsy at 6 months and 12 months. Results Although no mutations were identified in complement genes, functional studies were positive for C3 nephritic factors and elevated levels of soluble membrane attack complex (sMAC). On therapy, sMAC levels normalized and although proteinuria initially decreased, during therapy it increased reaching pre-treatment levels at 12 months. Although serum creatinine remained stable, repeat allograft biopsies showed progression of disease. Conclusions Clinical and histopathologic data suggest a partial response to eculizumab in this patient. While eculizumab blocked activation of the terminal complement cascade, persistent dysregulation of alternative pathway remained, showing that eculizumab alone cannot control disease in this patient. Additional research is required to identify effective anticomplement therapy for this group of C3G patients. PMID:23689905

  12. siRNA-Based Therapy Ameliorates Glomerulonephritis

    PubMed Central

    Shimizu, Hideki; Hori, Yuichi; Kaname, Shinya; Yamada, Koei; Nishiyama, Nobuhiro; Matsumoto, Satoru; Miyata, Kanjiro; Oba, Makoto; Yamada, Akira; Kataoka, Kazunori

    2010-01-01

    RNA interference by short interfering RNAs (siRNAs) holds promise as a therapeutic strategy, but use of siRNAs in vivo remains limited. Here, we developed a system to target delivery of siRNAs to glomeruli via poly(ethylene glycol)-poly(l-lysine)-based vehicles. The siRNA/nanocarrier complex was approximately 10 to 20 nm in diameter, a size that would allow it to move across the fenestrated endothelium to access to the mesangium. After intraperitoneal injection of fluorescence-labeled siRNA/nanocarrier complexes, we detected siRNAs in the blood circulation for a prolonged time. Repeated intraperitoneal administration of a mitogen-activated protein kinase 1 (MAPK1) siRNA/nanocarrier complex suppressed glomerular MAPK1 mRNA and protein expression in a mouse model of glomerulonephritis; this improved kidney function, reduced proteinuria, and ameliorated glomerular sclerosis. Furthermore, this therapy reduced the expression of the profibrotic markers TGF-β1, plasminogen activator inhibitor-1, and fibronectin. In conclusion, we successfully silenced intraglomerular genes with siRNA using nanocarriers. This technique could aid the investigation of molecular mechanisms of renal disease and has potential as a molecular therapy of glomerular diseases. PMID:20203158

  13. Ten-Year Follow-up of Patients with Epidemic Post Infectious Glomerulonephritis

    PubMed Central

    Pinto, Sergio Wyton L.; Mastroianni-Kirsztajn, Gianna; Sesso, Ricardo

    2015-01-01

    Background Scarce information on outcomes of epidemic post infectious glomerulonephritis is available. This is a 10-year follow-up of the patients that developed acute glomerulonephritis in an epidemic outbreak caused by group C Streptococcus zooepidemicus in Brazil in 1998, that were also previously evaluated 2 and 5 years after the acute episode. Methods In this prospective study 60 cases (out of 134 in 1998) were reevaluated after 10 years, as well as community controls matched by gender and age. They underwent clinical and renal function evaluation, including serum creatinine and cystatin C, estimated glomerular filtration rate (eGFR), albuminuria and hematuria. Results Comparisons of clinical and renal function aspects of 60 patients and 48 community controls have not shown significant differences (eGFR <60 ml/min/1.73m2 and/or albuminuria >30mg/g creatinine: 13.8% vs. 12.2%, respectively, p = 0.817) except for a higher frequency of hypertension in the cases (45.0% vs. 20.8%, p = 0.009). Comparing the same patients affected in the acute episode, 2, 5 and 10 years later, it was observed an improvement of median eGFR levels at 2 years and a trend toward subsequent stabilization in these levels, associated with decrease in albuminuria and increased hypertension rates in the last survey. At 10 years it was not observed additional reduction of renal function using serum creatinine, eGFR and cystatin C. Conclusions During the acute episode of epidemic GN a considerable proportion of patients presented hypertension and reduced renal function; after 2 years and particularly at this 10-year follow-up survey there was no worsening of renal function parameters, except for persistent higher frequency of hypertension. Nevertheless, a longer follow up is necessary to confirm that progressive loss of renal function will not occur. PMID:25962068

  14. Partial lipodystrophy, C3 nephritic factor and clinically inapparent mesangiocapillary glomerulonephritis.

    PubMed

    Bennett, W M; Bardana, E J; Wuepper, K; Houghton, D; Border, W A; Götze, O; Schreiber, R

    1977-05-01

    A case of partial lipodystrophy with C3 nephritic factor was found to be associated with mesangiocapillary glomerulonephritis although all clinical parameters of renal function were normal. Diagnosis of mesangiocapillary glomerulonephritis required renal biopsy. Nephriti factor obtained from this patient was immunochemically related to nephritic factor isolated from the serum of patients with typical mesangiocapillary glomerulonephritis without partial lipodystrophy. PMID:860726

  15. The Role of Nephritis-Associated Plasmin Receptor (NAPlr) in Glomerulonephritis Associated with Streptococcal Infection

    PubMed Central

    Oda, Takashi; Yoshizawa, Nobuyuki; Yamakami, Kazuo; Sakurai, Yutaka; Takechi, Hanako; Yamamoto, Kojiro; Oshima, Naoki; Kumagai, Hiroo

    2012-01-01

    It is well known that glomerulonephritis can occur after streptococcal infection, which is classically referred to as acute poststreptococcal glomerulonephritis (APSGN). The pathogenic mechanism of APSGN has been described by so-called immune complex theory, which involves glomerular deposition of nephritogenic streptococcal antigen and subsequent formation of immune complexes in situ and/or the deposition of circulating antigen-antibody complexes. However, the exact entity of the causative antigen has remained a matter of debate. We isolated a nephritogenic antigen for APSGN from the cytoplasmic fractions of group A streptococcus (GAS) depending on the affinity for IgG of APSGN patients. The amino acid and the nucleotide sequences of the isolated protein revealed to be highly identical to those of reported plasmin(ogen) receptor of GAS. Thus, we termed this antigen nephritis-associated plasmin receptor (NAPlr). Immunofluorescence staining of the renal biopsy tissues with anti-NAPlr antibody revealed glomerular NAPlr deposition in essentially all patients with early-phase APSGN. Furthermore, glomerular plasmin activity was detected by in situ zymography in the distribution almost identical to NAPlr deposition in renal biopsy tissues of APSGN patients. These data suggest that NAPlr has a direct, nonimmunologic function as a plasmin receptor and may contribute to the pathogenesis of APSGN by maintaining plasmin activity. PMID:23118507

  16. Granulomatosis with Polyangiitis Presenting as Pauci-Immune Crescentic Glomerulonephritis in Pregnancy

    PubMed Central

    Kunjal, Ryan; Makary, Raafat; Poenariu, Andreea

    2016-01-01

    Antineutrophil cytoplasmic antibody (ANCA) associated vasculitis rarely affects females of reproductive age. A 28-year-old African American woman presented at 8 weeks of gestation with intractable vomiting attributed to hyperemesis gravidarum. She was found to have acute kidney injury that was unresponsive to vigorous fluid resuscitation and urine sediment examination was suggestive of an underlying glomerulonephritis. Serum c-ANCA and PR3 were elevated and there was no peripheral eosinophilia. During her course she also developed one episode of small volume hemoptysis with right upper lobe infiltrates on CT Chest. There were no cutaneous manifestations of vasculitis or upper respiratory symptoms. Renal biopsy revealed a pauci-immune crescentic glomerulonephritis (PICGN). The diagnosis was consistent with granulomatosis with polyangiitis (GPA). Management initially comprised teratogen sparing agents; steroids, intravenous immunoglobulin; and plasma exchange. The response was suboptimal and she became dependent on daily renal replacement therapy. Ultimately the pregnancy was terminated allowing for traditional treatment approaches with dramatic effect. This is the first case of GPA presenting as PICGN in pregnancy and highlights the challenges of its management. PMID:27293925

  17. Classifying murine glomerulonephritis using optical coherence tomography and optical coherence elastography.

    PubMed

    Liu, Chih-Hao; Du, Yong; Singh, Manmohan; Wu, Chen; Han, Zhaolong; Li, Jiasong; Chang, Anthony; Mohan, Chandra; Larin, Kirill V

    2016-08-01

    Acute glomerulonephritis caused by antiglomerular basement membrane marked by high mortality. The primary reason for this is delayed diagnosis via blood examination, urine analysis, tissue biopsy, or ultrasound and X-ray computed tomography imaging. Blood, urine, and tissue-based diagnoses can be time consuming, while ultrasound and CT imaging have relatively low spatial resolution, with reduced sensitivity. Optical coherence tomography is a noninvasive and high-resolution imaging technique that provides superior spatial resolution (micrometer scale) as compared to ultrasound and CT. Changes in tissue properties can be detected based on the optical metrics analyzed from the OCT signals, such as optical attenuation and speckle variance. Furthermore, OCT does not rely on ionizing radiation as with CT imaging. In addition to structural changes, the elasticity of the kidney can significantly change due to nephritis. In this work, OCT has been utilized to quantify the difference in tissue properties between healthy and nephritic murine kidneys. Although OCT imaging could identify the diseased tissue, its classification accuracy is clinically inadequate. By combining optical metrics with elasticity, the classification accuracy improves from 76% to 95%. These results show that OCT combined with OCE can be a powerful tool for identifying and classifying nephritis. Therefore, the OCT/OCE method could potentially be used as a minimally invasive tool for longitudinal studies during the progression and therapy of glomerulonephritis as well as complement and, perhaps, substitute highly invasive tissue biopsies. Elastic-wave propagation in mouse healthy and nephritic kidneys. PMID:26791097

  18. Fundus changes in mesangiocapillary glomerulonephritis type II: vitreous fluorophotometry.

    PubMed Central

    Raines, M F; Duvall-Young, J; Short, C D

    1989-01-01

    We have described a complex abnormality of retinal pigment epithelium, Bruch's membrane, and choriocapillaris in mesangiocapillary glomerulonephritis (MCGN) type II. Patients with MCGN type II were examined by vitreous fluorophotometry which reveals that there is a breakdown of the blood retinal barrier (BRB) in those patients with the typical fundus lesions. The function of this barrier was calculated as a penetration ratio and was statistically greater in these patients when compared with a group of (a) normal persons, (b) patients with drusen, and (c) patients with other forms of glomerulonephritis. Images PMID:2605145

  19. Ionized Absorbers in AGN

    NASA Astrophysics Data System (ADS)

    Mathur, S.

    1999-08-01

    As a part of this program, we observed three AGN:PKS2251 + 113, PG0043 = 039 and PLH909. Two objects show signatures of absorbtion in their UV spectra. Based on our earlier modeling of X-ray warm absorbents, we expected to observe X-ray observation in these objects. The third, PLH909, is known to have soft excess in EINSTEIN data. Attachment: "Exploratory ASCA observation of broad absorption line quasi-stellar objects".

  20. Ionized Absorbers in AGN

    NASA Technical Reports Server (NTRS)

    Mathur, S.

    1999-01-01

    As a part of this program, we observed three AGN:PKS2251 + 113, PG0043 = 039 and PLH909. Two objects show signatures of absorbtion in their UV spectra. Based on our earlier modeling of X-ray warm absorbents, we expected to observe X-ray observation in these objects. The third, PLH909, is known to have soft excess in EINSTEIN data. Attachment: "Exploratory ASCA observation of broad absorption line quasi-stellar objects".

  1. Starburst or AGN dominance in submm-luminous candidate AGN

    NASA Astrophysics Data System (ADS)

    Coppin, Kristen; Alexander, Dave; Aretxaga, Itziar; Blain, Andrew; Chapman, Scott; Clements, Dave; Dunlop, James; Dunne, Loretta; Dye, Simon; Farrah, Duncan; Hughes, David; Ivison, Rob; Kim, Sungeun; Menendez-Delmestre, Karin; Oliver, Sebastian; Page, Mat; Pope, Alexandra; Rowan-Robinson, Michael; Scott, Douglas; Smail, Ian; Swinbank, Mark; Vaccari, Mattia; van Kampen, Eelco

    2008-03-01

    It is widely believed that starbursts/ULIRGs and AGN activity are triggered by galaxy interactions and merging; and sub-mm selected galaxies (SMGs) seem to be simply high redshift ULIRGs, observed near the peak of activity. In this evolutionary picture every SMG would host an AGN, which would eventually grow a black hole strong enough to blow off all of the gas and dust leaving an optically luminous QSO. In order to probe this evolutionary sequence, a crucial sub-sample to focus on would be the 'missing link' sources, which demonstrate both strong starburst and AGN signatures and to determine if the starburst is the main power source even in SMGs when we have evidence that an AGN is present. The best way to determine if a dominant AGN is present is to look in the mid-IR for their signatures, since often even deep X-ray observations miss identifying the presence of AGN in heavily dust-obscured SMGs. We have selected a sample of SMGs which are good candidates for harboring powerful AGN on the basis of their IRAC colours (S8um/S4.5um>2). Once we confirm these SMGs are AGN-dominated, we can then perform an audit of the energy balance between star-formation and AGN within this special sub-population of SMGs where the BH has grown appreciably to begin heating the dust emission. The proposed observations with IRS will probe the physics of how SMGs evolve from a cold-dust starburst-dominated ULIRG to an AGN/QSO by measuring the level of the mid-IR continuum, PAH luminosity, and Si absorption in these intermediate `transitory' AGN/SMGs.

  2. Pauci-Immune Crescentic Glomerulonephritis: An ANCA-Associated Vasculitis

    PubMed Central

    Syed, Rafeel; Rehman, Amina; Valecha, Gautam; El-Sayegh, Suzanne

    2015-01-01

    Rapidly progressive glomerulonephritis (RPGN) is a syndrome signified by a precipitous loss of renal function, with features of glomerulonephritis including dysmorphic erythrocyturia and glomerular proteinuria. RPGN is associated with extensive crescent formation, and, thus, the clinical term RPGN is often used interchangeably with the pathologic term crescentic glomerulonephritis (CGN). From an immunopathologic standpoint, primary RPGN is divided into pauci-immune GN (PICG), anti-GBM GN, and immune complex GN. PICG, the most common etiology of primary RPGN, refers to a necrotizing glomerulonephritis with few or no immune deposits by immunofluorescence (IF) or electron microscopy (EM). In most patients, pauci-immune CGN is a component of a systemic small vessel vasculitis such as granulomatosis with polyangiitis (GPA). Approximately 90% of patients with PICG have circulating ANCA antibodies, leading to the nomenclature ANCA-associated vasculitis (AAV). Recent research has identified several other antibodies associated with PICG, which is now understood to be a complex spectrum of disease with considerable overlap in terms of clinical phenotype and outcomes. In addition, several genetic and environmental factors have recently been implicated in the pathogenesis of this disorder. With new prognostic classifications, enhanced understanding of immunopathologic mechanisms, and novel treatment paradigms, clinical and experimental interest in PICG remains high. PMID:26688808

  3. Th1 and Th17 Cells Induce Proliferative Glomerulonephritis

    PubMed Central

    Summers, Shaun A.; Steinmetz, Oliver M.; Li, Ming; Kausman, Joshua Y.; Semple, Timothy; Edgtton, Kristy L.; Borza, Dorin-Bogdan; Braley, Hal; Holdsworth, Stephen R.

    2009-01-01

    Th1 effector CD4+ cells contribute to the pathogenesis of proliferative and crescentic glomerulonephritis, but whether effector Th17 cells also contribute is unknown. We compared the involvement of Th1 and Th17 cells in a mouse model of antigen-specific glomerulonephritis in which effector CD4+ cells are the only components of adaptive immunity that induce injury. We planted the antigen ovalbumin on the glomerular basement membrane of Rag1−/− mice using an ovalbumin-conjugated non-nephritogenic IgG1 monoclonal antibody against α3(IV) collagen. Subsequent injection of either Th1- or Th17-polarized ovalbumin-specific CD4+ effector cells induced proliferative glomerulonephritis. Mice injected with Th1 cells developed progressive albuminuria over 21 d, histologic injury including 5.5 ± 0.9% crescent formation/segmental necrosis, elevated urinary nitrate, and increased renal NOS2, CCL2, and CCL5 mRNA. Mice injected with Th17 cells developed albuminuria by 3 d; compared with Th1-injected mice, their glomeruli contained more neutrophils and greater expression of renal CXCL1 mRNA. In conclusion, Th1 and Th17 effector cells can induce glomerular injury. Understanding how these two subsets mediate proliferative forms of glomerulonephritis may lead to targeted therapies. PMID:19820122

  4. Th1 and Th17 cells induce proliferative glomerulonephritis.

    PubMed

    Summers, Shaun A; Steinmetz, Oliver M; Li, Ming; Kausman, Joshua Y; Semple, Timothy; Edgtton, Kristy L; Borza, Dorin-Bogdan; Braley, Hal; Holdsworth, Stephen R; Kitching, A Richard

    2009-12-01

    Th1 effector CD4+ cells contribute to the pathogenesis of proliferative and crescentic glomerulonephritis, but whether effector Th17 cells also contribute is unknown. We compared the involvement of Th1 and Th17 cells in a mouse model of antigen-specific glomerulonephritis in which effector CD4+ cells are the only components of adaptive immunity that induce injury. We planted the antigen ovalbumin on the glomerular basement membrane of Rag1(-/-) mice using an ovalbumin-conjugated non-nephritogenic IgG1 monoclonal antibody against alpha3(IV) collagen. Subsequent injection of either Th1- or Th17-polarized ovalbumin-specific CD4+ effector cells induced proliferative glomerulonephritis. Mice injected with Th1 cells developed progressive albuminuria over 21 d, histologic injury including 5.5 +/- 0.9% crescent formation/segmental necrosis, elevated urinary nitrate, and increased renal NOS2, CCL2, and CCL5 mRNA. Mice injected with Th17 cells developed albuminuria by 3 d; compared with Th1-injected mice, their glomeruli contained more neutrophils and greater expression of renal CXCL1 mRNA. In conclusion, Th1 and Th17 effector cells can induce glomerular injury. Understanding how these two subsets mediate proliferative forms of glomerulonephritis may lead to targeted therapies. PMID:19820122

  5. Models of AGN feedback

    NASA Astrophysics Data System (ADS)

    Combes, Françcoise

    2015-02-01

    The physical processes responsible of sweeping up the surrounding gas in the host galaxy of an AGN, and able in some circumstances to expel it from the galaxy, are not yet well known. The various mechanisms are briefly reviewed: quasar or radio modes, either momentum-conserving outflows, energy-conserving outflows, or intermediate. They are confronted to observations, to know whether they can explain the M-sigma relation, quench the star formation or whether they can also provide some positive feedback and how the black hole accretion history is related to that of star formation.

  6. Obscured accretion from AGN surveys

    NASA Astrophysics Data System (ADS)

    Vignali, Cristian

    2014-07-01

    Recent models of super-massive black hole (SMBH) and host galaxy joint evolution predict the presence of a key phase where accretion, traced by obscured Active Galactic Nuclei (AGN) emission, is coupled with powerful star formation. Then feedback processes likely self-regulate the SMBH growth and quench the star-formation activity. AGN in this important evolutionary phase have been revealed in the last decade via surveys at different wavelengths. On the one hand, moderate-to-deep X-ray surveys have allowed a systematic search for heavily obscured AGN, up to very high redshifts (z~5). On the other hand, infrared/optical surveys have been invaluable in offering complementary methods to select obscured AGN also in cases where the nuclear X-ray emission below 10 keV is largely hidden to our view. In this review I will present my personal perspective of the field of obscured accretion from AGN surveys.

  7. Urinary Thrombin: A Novel Marker of Glomerular Inflammation for the Diagnosis of Crescentic Glomerulonephritis (Prospective Observational Study)

    PubMed Central

    Kitamoto, Yasunori; Arizono, Kenji; Fukui, Hiroyoshi; Tomita, Kimio; Kitamura, Hiroshi; Taguma, Yoshio; Imamura, Takahisa

    2015-01-01

    Background Crescentic glomerulonephritis (CresGN), an uncommon rapidly progressive disease, is characterized by severe glomerular inflammation with fibrin deposition. The lack of specific CresGN biomarkers delays diagnosis and threatens life. Because fibrin deposits in CresGN glomeruli indicate thrombin generation, we hypothesized that thrombin is excreted in urine and is a specific CresGN biomarker. Methods We measured urinary thrombin activity in 200 untreated patients (17 with CresGN, 183 with primary glomerulonephritis) and controls (8 patients with healed CresGN, 11 with nephrosclerosis, and 10 with tubulointerstitial nephritis, and 66 healthy volunteers). CresGN types included 15 pauci-immune and 2 immune complex. We assessed the diagnostic accuracy of thrombinuria in 169 patients with hematuria and proteinuria. Renal biopsy tissues were immunostained for tissue factor and fibrin. We analyzed the relationship of thrombinuria to plasma thrombin-antithrombin complex, hematuria, proteinuria, glomerular filtration rate, glomerular fibrin deposition, antineutrophil cytoplasmic antibodies (ANCAs), and C-reactive protein (CRP). We studied changes in thrombin activities after glucocorticoid treatment in 12 patients with thrombinuria. Results The highest thrombinuria occurrence was in CresGN (70.6%), followed by membranoproliferative glomerulonephritis (41.7%), IgA nephropathy (9.2%), and acute glomerulonephritis (0%). More than 75% of patients with nonproliferative glomerulonephritis manifested no thrombinuria. No controls had thrombinuria. Thrombinuria showed high CresGN specificity (90.1%) and moderate sensitivity (70.6%) and was detected in 4 of 7 patients with ANCA-negative CresGN. In CresGN, thrombinuria was associated with fibrin deposition in glomerular extracapillary tissue, where monocytes/macrophages expressed tissue factor. Thrombinuria in CresGN was unrelated to plasma thrombin-antithrombin complex, hematuria, proteinuria, glomerular filtration rate, and

  8. Starburst or AGN Dominance in Submillimetre-Luminous Candidate AGN?

    NASA Astrophysics Data System (ADS)

    Coppin, Kristen; Pope, Alexandra; Menéndez-Delmestre, Karín; Alexander, David M.; Dunlop, James

    2010-06-01

    It is widely believed that ultraluminous infrared (IR) galaxies and active galactic nuclei (AGN) activity are triggered by galaxy interactions and merging, with the peak of activity occurring at z~2, where submillimetre galaxies are thousands of times more numerous than local ULIRGs. In this evolutionary picture, submillimetre galaxies (SMGs) would host an AGN, which would eventually grow a black hole (BH) strong enough to blow off all of the gas and dust leaving an optically luminous QSO. To probe this evolutionary sequence we have focussed on the `missing link' sources, which demonstrate both strong starburst (SB) and AGN signatures, in order to determine if the SB is the main power source even in SMGs when we have evidence that an AGN is present from their IRAC colours. The best way to determine if a dominant AGN is present is to look for their signatures in the mid-infrared with the Spitzer IRS, since often even deep X-ray observations miss identifying the presence of AGN in heavily dust-obscured SMGs. We present the results of our audit of the energy balance between star-formation and AGN within this special sub-population of SMGs-where the BH has grown appreciably to begin heating the dust emission.

  9. AGN from HeII: AGN host galaxy properties & demographics

    NASA Astrophysics Data System (ADS)

    Baer, Rudolf E.; Schawinski, Kevin; Weigel, Anna

    2016-01-01

    We present an analysis of HeII emitting objects classified as AGN. In a sample of 81'192 galaxies taken from the seventh data release (DR7) of the Sloan Digital Sky Survey in the redshift interval 0.02 < z < 0.05 and with r < 17 AB mag, the Baldwin, Philips & Terlevitsch 1981 method (BPT) identifies 1029 objects as active galactic nuclei. By applying an analysis using HeII λ 4686 emission lines, based on Shirazi & Binchmann 2012, we have identified an additional 283 active galactic nuclei, which were missed by the BPT method. This represents an increase of over 25 %. The characteristics of the HeII selected AGN are different from the AGN found through the PBT; the colour - mass diagram and the colour histogram both show that HeII selected AGN are bluer. This new selection technique can help inform galaxy black hole coevolution scenarios.

  10. Congenital syphilis and glomerulonephritis with evidence for immune pathogenesis

    PubMed Central

    Wiggelinkhuizen, J.; Kaschula, R. O. C.; Uys, C. J.; Kuijten, R. H.; Dale, J.

    1973-01-01

    In 3 infants with congenital syphilis the dominant clinical manifestation of syphilitic kidney disease was the nephrotic syndrome. Mesangioendothelial proliferation was present in 2 cases and mixed proliferative glomerulonephritis with crescent formation in the third. The severity of the clinical and histopathological abnormalities could be related to the apparent duration of the illness. In all 3 cases immune complex deposition could be shown within and along the epithelial aspect of the glomerular basement membrane on light, electron, and immunofluorescent microscopy. These features, together with a reduced total serum haemolytic complement, suggest an immune pathogenesis of the glomerulonephritis associated with early congenital syphilis. ImagesFIG. 1FIG. 2FIG. 3FIG. 4FIG. 5 PMID:4267344

  11. AGN Science: The Past, The Present, The Future . AGN Science

    NASA Astrophysics Data System (ADS)

    Boller, Th.

    I review some basic results on AGN science by concentrating on the Fe K and Fe L line observations and on the Narrow-Line Seyfert 1 physics. This paper is based on a talk given at the Vulcano workshop, 'The multifrequency behavior of high energy cosmic sources` in 2009. Given the length of the talk and the number of pages the review on AGN science cannot be complete and is biased towards two science topics and my personal view.

  12. Antineutrophil cytoplasmic autoantibody-associated glomerulonephritis in children.

    PubMed

    Hattori, M; Kurayama, H; Koitabashi, Y

    2001-07-01

    Aretrospective investigation was conducted by members of the Japanese Society for Pediatric Nephrology from 1990 to 1997 to define the clinical features and outcome of antineutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis in children. Thirty-four ANCA-seropositive Japanese pediatric patients with biopsy-proven pauci-immune necrotizing crescentic glomerulonephritis were identified. Of these, 3 cases associated with Wegener's granulomatosis were excluded because of the small sample size. Among the 31 patients studied, 10 had a diagnosis of necrotizing crescentic glomerulonephritis alone and 21 had microscopic polyangiitis. Females predominated (87%), and the median age at onset was 12 yr. Twenty-six patients received treatment with cyclophosphamide and corticosteroids, and five patients received treatment with corticosteroids alone; 84% of patients achieved remission, and 39% of responders relapsed in a median of 24 mo. ANCA titers correlated with response to treatment and disease activity, with some exceptions. Patients were followed for a median of 42 mo (range, 3 to 96 mo). Nine of 31 patients (29.0%) progressed to end-stage renal disease, 6 (19.4%) had reduced renal function, and 15 (48.4%) had normal renal function at the last observation. One patient (3.2%) died from cytomegalovirus infection 3 mo after initiation of therapy. Life-table analysis showed 75% renal survival at 39 mo. Patients who subsequently developed end-stage renal disease (n = 9) had significantly higher average peak serum creatinine levels and more chronic pathologic lesions at diagnosis compared with patients with favorable renal outcome (n = 15). In conclusion, our clinical experience suggests that the clinical disease spectrum of ANCA-associated glomerulonephritis is similar in pediatric and adult patients, but there is a female predominance in children. PMID:11423578

  13. Crescentic glomerulonephritis in a child with Heiner syndrome.

    PubMed

    Yavuz, Sevgi; Karabay-Bayazıt, Aysun; Yılmaz, Mustafa; Gönlüşen, Gülfiliz; Anarat, Ali

    2014-01-01

    Heiner syndrome is a food-induced pulmonary hypersensitivity disease that predominantly affects infants. Chronic respiratory symptoms with pulmonary infiltrates on radiography, positive milk precipitins and resolution of findings upon removal of cow's milk constitute the main features. Severe cases may present with pulmonary hemosiderosis. Few renal manifestations associated with this syndrome have been reported so far. Here we report the first case of Heiner syndrome complicated by crescentic glomerulonephritis after 5 years of follow-up. PMID:26388600

  14. Posterior segment findings in a patient with immunotactoid glomerulonephritis

    PubMed Central

    Gupta, Aditi; Prabhu, Rangarajan Venugopal; Patel, Amit K.; Sivaraj, Ramesh

    2015-01-01

    Purpose: To present a case with posterior segment findings in a patient with cloudy corneas secondary to immunotactoid glomerulonephritis (ITG). Methods: A 57-year-old female was known to have bilateral cloudy corneas diagnosed 12 years ago secondary to immunotactoid glomerulonephritis. Clinically, fundus examination was difficult to visualise due to the density of her corneal opacities. Results: B-scan ultrasound revealed significant retino-choroidal & non-inflammatory scleral thickening. The macula also showed signs of thickening in both eyes. Optical coherence tomography (OCT) showed thinning of the inner retinal layers and significant choroidal folds in both eyes. Electrodiagnostic tests (EDT) concluded loss of retinal ganglion cells with preservation of retinal function in both eyes. Conclusion: This case widens the spectrum of findings seen in patients diagnosed with Immunotactoid Glomerulonephritis and alerts us to undertake detailed posterior segment examination where possible. Ocular coherence tomography (OCT) and B-scan ultrasonography are important adjuvants to help assess the posterior segment in patients with corneal opacities secondary to ITG.

  15. Hydrogen Peroxide–Inducible Clone-5 Regulates Mesangial Cell Proliferation in Proliferative Glomerulonephritis in Mice

    PubMed Central

    Jamba, Ariunbold; Kondo, Shuji; Urushihara, Maki; Nagai, Takashi; Kim-Kaneyama, Joo-ri; Miyazaki, Akira; Kagami, Shoji

    2015-01-01

    Hydrogen peroxide-inducible clone-5 (Hic-5) is a transforming growth factor (TGF)-β1-inducible focal adhesion protein. We previously demonstrated that Hic-5 was localized in mesangial cells and its expression was associated with glomerular cell proliferation and matrix expansion in human and rat glomerulonephritis (GN). In the present study, we first assessed the role of Hic-5 in mesangioproliferative GN by injecting Habu venom into heminephrectomized wild type (Hic-5+/+) and Hic-5-deficient (Hic-5-/-) mice. Hic-5+/+ GN mice exhibited glomerular cell proliferation on day 7. Surprisingly, glomerular cell number and Ki-67-positive cells in Hic-5-/- GN mice were significantly greater than those in Hic-5+/+ GN mice on day 7, although the number of glomerular apoptotic cells and the expression of growth factors (platelet-derived growth factor-BB and TGF-β1) and their receptors were similarly increased in both Hic-5+/+ and Hic-5-/- GN mice. In culture experiments, proliferation assays showed that platelet-derived growth factor-BB and TGF-β1 enhanced the proliferation of Hic-5-/- mesangial cells compared with Hic-5+/+ mesangial cells. In addition, mitogenic regulation by Hic-5 was associated with altered and coordinated expression of cell cycle-related proteins including cyclin D1 and p21. The present results suggest that Hic-5 might regulate mesangial cell proliferation in proliferative GN in mice. In conclusion, modulation of Hic-5 expression might have a potential to prevent mesangial cell proliferation in the acute mitogenic phase of glomerulonephritis. PMID:25835392

  16. [Autoimmune hepatitis and membranous glomerulonephritis under immune therapy in chronic hepatitis C].

    PubMed

    Paparoupa, Maria; Huy Ho, Ngoc Ahn; Schuppert, Frank

    2016-05-01

    A 63-year-old patient is evaluated for an unclear weight loss with general malaise and fatigue for several months. Serological examination reveales the first diagnosis of a hepatitis-C-virus-genotype-1b-infection with an initial viral load of 980 000 IU / ml. The duration of the infection is suggested to be more than 6 months. Because of the initially elevated anti-nuclear-antibodies (ANA) the diagnosis of an autoimmune hepatitis needs to be excluded. All other liver related autoantibodies and the immunoglobulins (Ig) IgG, IgA and IgM are normal. A liver biopsy is conducted. After a short test with non-pegylated interferon (IFN) liver enzymes remain stable and treatment with pegylated IFN-alfa-2a and ribavirin (RBV) is initiated. The patient is a "rapid viral responder" and his viral load is found under the detection limit within 4 weeks under therapy. On the 16th week, liver enzymes increase rapidly. ANA's and IgG-immunoglobulins are positive. A second lever biopsy does not confirm the diagnosis of autoimmune hepatitis and the treatment is continued under careful observation of all relevant liver parameters. 21 weeks after the initiation of the treatment, massive peripheral edema, hypoproteinemia and proteinuria are observed. The renal biopsy reveales membranous glomerulonephritis. Because of the preserved renal function, no acute immunosuppression is initiated and the treatment gets completed after overall 24 weeks. Liver and renal parameters return quickly back to normal after treatment discharge. This is the first report of a combined autoimmune reaction with development of autoimmune hepatitis and glomerulonephritis under INF and RBV antiviral therapy for a chronic hepatitis-C-infection. The occurrence of autoimmune manifestations should especially be considered in genetically susceptible individuals or those with positive autoimmunity markers. The initiation of INF for the treatment of chronic hepatitis-C-infection has to be critically evaluated since

  17. AGN and their host galaxies

    NASA Astrophysics Data System (ADS)

    Steinborn, L. K.; Dolag, K.; Hirschmann, M.; Remus, R.-S.; Teklu, A. F.

    2016-06-01

    Large scale cosmological hydrodynamic simulations are an important tool to study the co-evolution between black holes (BHs) and their host galaxies. However, in order to model the accretion onto BHs and AGN feedback we need sub-grid models which contain several free parameters. The choice of these parameters has a significant impact on the properties of the BHs and their host galaxies. Therefore, we improve the accretion model and the AGN feedback model based on both theory and observations to eliminate most free parameters. In that way, the slope of the observed relation between BH mass and stellar mass is reproduced self-consistently. We performed a few extremely large simulation runs as part of the Magneticum Pathfinder simulation set, combining a high resolution with very large cosmological volumes, enabling us to study for example dual AGN, the role of galaxy mergers and AGN clustering properties.

  18. Accretion Timescales from Kepler AGN

    NASA Astrophysics Data System (ADS)

    Kasliwal, Vishal P.; Vogeley, Michael S.; Richards, Gordon T.

    2015-01-01

    We constrain AGN accretion disk variability mechanisms using the optical light curves of AGN observed by Kepler. AGN optical fluxes are known to exhibit stochastic variations on timescales of hours, days, months and years. The excellent sampling properties of the original Kepler mission - high S/N ratio (105), short sampling interval (30 minutes), and long sampling duration (~ 3.5 years) - allow for a detailed examination of the differences between the variability processes present in various sub-types of AGN such as Type I and II Seyferts, QSOs, and Blazars. We model the flux data using the Auto-Regressive Moving Average (ARMA) representation from the field of time series analysis. We use the Kalman filter to determine optimal mode parameters and use the Akaike Information Criteria (AIC) to select the optimal model. We find that optical light curves from Kepler AGN cannot be fit by low order statistical models such as the popular AR(1) process or damped random walk. Kepler light curves exhibit complicated power spectra and are better modeled by higher order ARMA processes. We find that Kepler AGN typically exhibit power spectra that change from a bending power law (PSD ~ 1/fa) to a flat power spectrum on timescales in the range of ~ 5 - 100 days consistent with the orbital and thermal timescales of a typical 107 solar mass black hole.

  19. AGN Observations with STACEE

    NASA Astrophysics Data System (ADS)

    Bramel, D. A.; Boone, L. M.; Carson, J.; Chae, E.; Covault, C. E.; Fortin, P.; Gingrich, D. M.; Hanna, D. S.; Hinton, J. A.; Mukherjee, R.; Mueller, C.; Ong, R. A.; Ragan, K.; Scalzo, R. A.; Schuette, D. R.; Theoret, C. G.; Williams, D. A.; Wong, J.; Zweerink, J.

    2003-03-01

    The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is a gamma-ray detector designed to study astrophysical sources at energies between 50 and 500 GeV. It uses 64 large, steerable mirrors at the National Solar Tower Test Facility near Albuquerque, NM, USA to collect Cherenkov light from extended air showers and concentrate it onto an array of photomultiplier tubes. The large light-collection area gives it a lower energy threshold than imaging-type Cherenkov detectors. STACEE is now fully operational, and we report here on the performance of the complete STACEE instrument, as well as preliminary results of recent observations of several AGN targets. This work was supported in part by the National Science Foundation (under Grant Numbers PHY-9983836, PHY-0070927, and PHY-0070953), the Natural Sciences and Engineering Research Council, Le Fond Quebecois de la Recherche sur la Nature et les Technologies (FQRNT), the Research Corporation, and the California Space Institute. CEC is a Cottrell Scholar of the Research Corporation.

  20. Pulmonary alveolar proteinosis and glomerulonephritis in lysinuric protein intolerance: case reports and autopsy findings of four pediatric patients.

    PubMed

    Parto, K; Kallajoki, M; Aho, H; Simell, O

    1994-04-01

    Lysinuric protein intolerance is an autosomal recessive disease caused by defective transport of cationic amino acids. Of the 38 lysinuric protein intolerance patients diagnosed in Finland since 1965, four pediatric patients have died. We describe the clinical courses and autopsy findings for these patients. All patients developed acute respiratory insufficiency. In addition to pulmonary hemorrhages, three of the patients had pulmonary alveolar proteinosis and one had cholesterol granulomas. Three patients had a clinically obvious renal insufficiency, but all four showed histologic signs of immune complex-mediated glomerulonephritis. The patients also developed hepatic insufficiency with fatty degeneration or cirrhosis. All patients showed anemia, thrombocytopenia, and a severe bleeding tendency. The bone marrow of three patients was hypercellular, but the amount of megakaryocytes was decreased in two cases. Amyloid was present in the lymph nodes and the spleen. Bone specimens showed osteoporosis. We conclude that pediatric patients with lysinuric protein intolerance are predisposed to develop pulmonary alveolar proteinosis and glomerulonephritis. They are also at risk of protein malnutrition in the active growth phase, probably due to higher requirements for total nitrogen and amino acids. PMID:8163273

  1. Proliferative Glomerulonephritis with Monoclonal IgG Deposits

    PubMed Central

    Satoskar, Anjali; Markowitz, Glen S.; Valeri, Anthony M.; Appel, Gerald B.; Stokes, Michael B.; Nadasdy, Tibor; D'Agati, Vivette D.

    2009-01-01

    Dysproteinemias that result in monoclonal glomerular deposits of IgG are relatively uncommon. Here, we report the largest series of proliferative glomerulonephritis with monoclonal IgG deposits, a form of renal involvement by monoclonal gammopathy that mimics immune-complex glomerulonephritis. We retrospectively identified 37 patients, most of whom were white (81%), female (62%), or older than 50 yr (65%). At presentation, 49% had nephrotic syndrome, 68% had renal insufficiency, and 77% had hematuria. In 30% of the patients, we identified a monoclonal serum protein with the same heavy- and light-chain isotypes as the glomerular deposits (mostly IgG1 or IgG2), but only one patient had myeloma. Histologic patterns were predominantly membranoproliferative (57%) or endocapillary proliferative (35%) with membranous features. Electron microscopy revealed granular, nonorganized deposits, and immunofluorescence demonstrated glomerular deposits that stained for a single light-chain isotype and a single heavy-chain subtype, most commonly IgG3κ (53%). During an average of 30.3 mo of follow-up for 32 patients with available data, 38% had complete or partial recovery, 38% had persistent renal dysfunction, and 22% progressed to ESRD. Correlates of ESRD on univariate analysis were higher creatinine at biopsy, percentage of glomerulosclerosis, and degree of interstitial fibrosis but not immunomodulatory treatment or presence of a monoclonal spike. On multivariate analysis, higher percentage of glomerulosclerosis was the only independent predictor of ESRD. Only one patient lacking a monoclonal spike at presentation subsequently developed a monoclonal spike and no patient with a monoclonal spike at presentation subsequently developed a hematologic malignancy. We conclude that proliferative glomerulonephritis with monoclonal IgG deposits does not seem to be a precursor of myeloma in the vast majority of patients. PMID:19470674

  2. Monoclonal gammopathy associated membranous glomerulonephritis: A rare entity

    PubMed Central

    Gowda, K. K.; Joshi, K.; Ramachandran, R.; Nada, R.

    2015-01-01

    A 40-year-old male presented with nephrotic syndrome. Light microscopic analysis of the renal biopsy showed thickening of the glomerular capillary wall. Immunofluorescence examination revealed granular deposition of monoclonal immunoglobulin (Ig) G3-kappa and complement C3 along the glomerular basement membrane. Electron microscopy showed subepithelial electron dense deposits, thus confirming membranous glomerulonephritis (MGN) with monoclonal gammopathy. MGN with monoclonal gammopathy is an extremely rare but distinctive entity. This patient was treated with a combination of bortezomib, thalidomide and dexamethasone and showed partial remission of his nephrotic state and dysproteinemia. PMID:25684873

  3. Fibrillary glomerulonephritis associated with limited scleroderma: a case report.

    PubMed

    Nakhoul, Georges N; Simon, James F

    2016-04-01

    Fibrillary glomerulonephritis (GN) is a rare glomerular disorder that has been associated with monoclonal gammopathies, malignancies, chronic infections, and autoimmune disorders. We present the case of a 56-year-old woman with limited-type scleroderma and remote discoid lupus, evaluated for dipstick positive hematuria and preserved kidney function. Serologies were negative. Kidney biopsy revealed fibrillary GN. Her renal function and proteinuria remain stable 4 years after her initial diagnosis. This case is unusual both in its presentation and evolution, but mostly because it is the first reported case of fibrillary GN in association with limited type scleroderma. PMID:26709524

  4. Effect of cyclosporin on immune complex deposition in murine glomerulonephritis.

    PubMed Central

    Quinn, D G; Fennell, J S; Sheils, O; Gaffney, E F; Feighery, C F

    1991-01-01

    Chronic glomerulonephritis (GN) was induced in N/M mice by daily injections of human serum albumin (HSA). The glomerular lesion was similar to that observed in human membranous GN and was characterized by intense mesangial and capillary loop immunofluorescent staining for HSA, IgG and C3. Electron microscopic examination revealed numerous electron-dense deposits in the mesangium and along the subepithelial side of the glomerular basement membrane, the latter deposits being associated with membranous spikes. Chronically injected mice that had been treated with cyclosporin (CsA) from Day 1 had different patterns of immune complex deposition. Mesangial deposition was apparently unaltered but no subepithelial deposits or spikes were evident. In addition, only two out of 21 HSA-injected mice which began CsA treatment on Day 21 had subepithelial deposits. There was no significant difference in serum levels of HSA-specific IgG between the three groups of mice. CsA treatment would therefore appear to ameliorate the immunopathology of antigen-induced glomerulonephritis in this model without affecting serum antibody levels, and may be of therapeutic value in the treatment of human membranous GN. Images Figure 1 Figure 2 Figure 3 PMID:1828056

  5. Membranoproliferative glomerulonephritis: the role for laser microdissection and mass spectrometry.

    PubMed

    Jain, Deepika; Green, Jamie A; Bastacky, Sheldon; Theis, Jason D; Sethi, Sanjeev

    2014-02-01

    Monoclonal gammopathy is increasingly recognized as a common cause of membranoproliferative glomerulonephritis (MPGN); however, establishing this diagnosis can be challenging. We report the case of a 58-year-old asymptomatic woman who presented with proteinuria with protein excretion of 5,000mg/d, microscopic hematuria, and normal kidney function. Kidney biopsy was consistent with MPGN pattern of injury. Immunofluorescence studies were positive for nonspecific segmental immunoglobulin M (IgM) and C3 staining. Electron microscopy showed subendothelial, subepithelial, and mesangial electron-dense deposits. The workup excluded an infectious or autoimmune disease, but IgG κ monoclonal protein was detected in serum at a concentration of 0.4mg/dL. Because there was a mismatch between the serum monoclonal protein (IgG κ) and immunofluorescence staining pattern (nonspecific IgM, no light chain restriction), laser microdissection and mass spectrometry were performed on the kidney biopsy tissue. This identified the deposits as monoclonal IgG κ, thereby leading to the diagnosis of monoclonal gammopathy-associated MPGN. Our case emphasizes the importance of searching for an underlying cause of MPGN, reviews the technique of laser microdissection-mass spectrometry, and highlights its application as a pathology tool for the evaluation of monoclonal gammopathy-related glomerulonephritis. PMID:24145022

  6. Pauci-Immune Crescentic Glomerulonephritis in Connective Tissue Disease

    PubMed Central

    Cronin, Mary; Robin, Adam; Lorna, Campbell; Rosenthal, Ann K.

    2016-01-01

    Pauci-immune crescentic glomerulonephritis is commonly seen in ANCA-associated vasculitis but it is rarely seen during the course of other connective tissue diseases like lupus or Sjogren's syndrome or MCTD. We report 3 cases of pauci-immune crescentic glomerulonephritis in patients with connective tissue disease other than vasculitis. We reviewed literature and made summary of previously reported cases of this rare entity. Clinical and laboratory features of these patients varied widely, but most of patients have met criteria for lupus. In this small population of patients there is no correlation with ANCAs. Most of the patients were treated with aggressive immunosuppression and did well if they were treated early in the course of their disease. One of our patients required renal transplant, but she presented late in the course of her disease, as evidenced by chronicity on her renal biopsy. Whether these patients are overlap of vasculitis and other connective tissue diseases or to be considered as a separate entity is yet to be described. Clinicians must be aware of these presentations because initial presentation can be severe. PMID:27504208

  7. Rituximab therapy for primary glomerulonephritis: Report on two cases

    PubMed Central

    Fabrizi, Fabrizio; Cresseri, Donata; Fogazzi, Giovanni B; Moroni, Gabriella; Passerini, Patrizia; Martin, Paul; Messa, Piergiorgio

    2015-01-01

    The evidence in the medical literature on the efficacy and safety of rituximab therapy for primary glomerulonephritis is limited and controversial. We describe two male Caucasian patients with rapidly progressive kidney failure due to primary proliferative glomerulonephritis. Both of them received high-dose intravenous corticosteroids and oral cyclophosphamide with limited benefit. The first patient (hepatitis C virus-negative mixed cryoglobulinemia) underwent plasma-exchange with intravenous immunoglobulins; he showed significant benefit on kidney function (he became dialysis independent with serum creatinine going back to 1.6 mg/dL) after one rituximab pulse even if urinary abnormalities were still present. No improvement in renal function or urinary changes occurred in the second patient. Both these individuals developed sepsis over the follow-up, the first patient died two months after rituximab therapy. This report is in keeping with the occurrence of severe infections after rituximab therapy in patients with renal impairment at baseline and concomitant high-dose steroids. PMID:26301235

  8. Pauci-Immune Crescentic Glomerulonephritis in Connective Tissue Disease.

    PubMed

    Yeturi, Supraja; Cronin, Mary; Robin, Adam; Lorna, Campbell; Rosenthal, Ann K

    2016-01-01

    Pauci-immune crescentic glomerulonephritis is commonly seen in ANCA-associated vasculitis but it is rarely seen during the course of other connective tissue diseases like lupus or Sjogren's syndrome or MCTD. We report 3 cases of pauci-immune crescentic glomerulonephritis in patients with connective tissue disease other than vasculitis. We reviewed literature and made summary of previously reported cases of this rare entity. Clinical and laboratory features of these patients varied widely, but most of patients have met criteria for lupus. In this small population of patients there is no correlation with ANCAs. Most of the patients were treated with aggressive immunosuppression and did well if they were treated early in the course of their disease. One of our patients required renal transplant, but she presented late in the course of her disease, as evidenced by chronicity on her renal biopsy. Whether these patients are overlap of vasculitis and other connective tissue diseases or to be considered as a separate entity is yet to be described. Clinicians must be aware of these presentations because initial presentation can be severe. PMID:27504208

  9. Spontaneous remission of membranous glomerulonephritis with successful fetal outcome

    PubMed Central

    Huang, Yan-Mei; Zhou, Hui-Rong; Zhang, Ling; Yang, Ke-Ke; Luo, Jiang-Xi; Zhao, Hai-Lu

    2016-01-01

    Abstract Membranous glomerulonephritis (MGN) represents an immunologically mediated disease characterized by deposition of immune complexes in the glomerular subepithelial space. Persistent proteinuria at diagnosis predicts poor prognosis. Pregnancy with MGN is a risk of fetal loss and may worsen maternal renal function. Here, we report a lady with MGN and proteinuria achieved spontaneous remission and successful fetal outcome naive to any medications. The 26-year old woman had 1-year history of persistent proteinuria (5.5–12.56 g/24 hours) and biopsy-proven MGN. Histopathological characteristics included glomerular basement membrane spikes, subepithelial monoclonal IgG immunofluorescence, and diffuse electron dense deposits. She was sticking to a regular morning exercise routine without any medications. After successful delivery of a full-term baby girl, the mother had improved proteinuria (0.56 g/24 hours) and albuminuria (351.96 g/24 hours contrasting 2281.6 g/24 hours before pregnancy). The baby had normal height and body weight at 4 months old. We identified more pregnancies with MGN in 5 case reports and 5 clinical series review articles (7–33 cases included). Spontaneous remission of maternal MGN with good fetal outcome rarely occurred in mothers on immunosuppressive therapy. Mothers naive to immunosuppressive therapy may achieve spontaneous remission of maternal membranous glomerulonephritis and successful fetal outcome. Theoretically, fetus might donate stem cells to heal mother's kidney. PMID:27368022

  10. Familial C4B Deficiency and Immune Complex Glomerulonephritis

    PubMed Central

    Soto, K; Wu, YL; Ortiz, A; Aparício, SR; Yu, CY

    2010-01-01

    Homozygous complement C4B deficiency is described in a Southern European young female patient with Membranoproliferative Glomerulonephritis (MPGN) type III characterized by renal biopsies with strong complement C4 and IgG deposits. Low C4 levels were independent of clinical evolution or type of immunosuppression and were found in three other family members without renal disease or infections. HLA typing revealed that the patient has homozygous A*02, Cw*06, B*50 at the class I region, and DRB1*08 and DQB1*03 at the class II region. Genotypic and phenotypic studies demonstrated that the patient has homozygous monomodular RCCX in the HLA class III region, with single long C4A genes coding for C4A3 and complete C4B deficiency. Her father, mother, son and niece have heterozygous C4B deficiency. The patient’s deceased brother had a history of Henoch-Schönlein Purpura (HSP), an immune complex-mediated proliferative glomerulonephritis. These findings challenge the putative pathophysiological roles of C4A and C4B and underscore the need to perform functional assays, C4 allotyping and genotyping on patients with persistently low serum levels of a classical pathway complement component and glomerulopathy associated with immune deposits. PMID:20580617

  11. Multiwavelength AGN Surveys and Studies (IAU S304)

    NASA Astrophysics Data System (ADS)

    Mickaelian, Areg M.; Sanders, David B.

    2014-08-01

    1. Historical surveys: spectral and colorimetric surveys for AGN, surveys for UV-excess galaxies; 2. AGN from IR/submm surveys: 2MASS, IRAS, ISO, AKARI, SCUBA, SST, WISE, Herschel; 3. AGN from radio/mm surveys: NVSS, FIRST, ALMA, Planck, and others; 4. AGN from X-ray/gamma-ray surveys: ROSAT, ASCA, BeppoSAX, Chandra, XMM, INTEGRAL, Fermi, HESS, MAGIC, VERITAS, NuSTAR; 5. Multiwavelength AGN surveys, AGN statistics and cross-correlation of multiwavelength surveys; 6. Unification and other models of AGN, accretion modes, understanding of the structure of nearby AGN from IFUs on VLT and other telescopes; 7. AGN feedback in galaxies and clusters, AGN host galaxies and the AGN environments; 8. Binary AGN and Merging Super-Massive Black Holes; 9. Study of unique AGN, AGN variability and the Phenomena of Activity; 10. Future large projects; Author index.

  12. The Close AGN Reference Survey (CARS)

    NASA Astrophysics Data System (ADS)

    Rothberg, Barry; Husemann, Bernd; Busch, Gerold; Dierkes, Jens; Eckart, Andreas; Krajnovic, Davor; Scharwaechter, Julia; Tremblay, Grant R.; Urrutia, Tanya

    2015-08-01

    We present the first science results from the Close AGN Reference Survey (CARS). This program is a snapshot survey of 39 local type 1 AGN (0.01 < z <0.06) designed to address the issue of AGN-driven star formation quenching by characterizing the condition for star formation in AGN host galaxies. The primary sample was observed with Multi Unit Spectrscopic Explorer (MUSE), an optical wavelength integral field unit (IFU) with a 1'x1' field of view on the VLT. The optical 3D spectroscopy complements existing sub-mm CO(1-0) data and near-IR imaging to establish a unique dataset combining molecular and stellar masses with star formation rates, gas, stellar kinematics and AGN properties. The primary goals of CARS are to:1) investigate if the star formation efficiency and gas depletion time scales are suppressed as a consequence of AGN feedback; 2) identify AGN-driven outflows and their relation to the molecular gas reservoir of the host galaxy; 3) investigate the the balance of AGN feeding and feedback through the ratio of the gas reservoir to the AGN luminosity; and 4) provide the community with a reference survey of local AGN with a high legacy value. Future work will incorporate near-infrared IFU observations to present a complete spatially resolved picture of the interplay among AGN, star-formation, stellar populations, and the ISM.

  13. THE GALACTIC SPIN OF AGN GALAXIES

    SciTech Connect

    Cervantes-Sodi, Bernardo; Hernandez, X.; Park, Changbom; Choi, Yun-Young E-mail: xavier@astroscu.unam.mx

    2011-07-01

    Using an extensive sample of galaxies selected from the Sloan Digital Sky Survey Data Release 5, we compare the angular momentum distribution of active galactic nuclei (AGNs) with non-AGN hosting late-type galaxies. To this end we characterize galactic spin through the dimensionless angular momentum parameter {lambda}, which we estimate through simple dynamical considerations. Using a volume-limited sample, we find a considerable difference when comparing the empirical distributions of {lambda} for AGNs and non-AGN galaxies, the AGNs showing typically low {lambda} values and associated dispersions, while non-AGNs present higher {lambda} values and a broader distribution. A more striking difference is found when looking at {lambda} distributions in thin M{sub r} cuts; while the spin of non-AGN galaxies presents an anticorrelation with M{sub r} , with bright (massive) galaxies having low spins, AGN host galaxies present uniform values of {lambda} at all magnitudes, a behavior probably imposed by the fact that most late-type AGN galaxies present a narrow range in color, with a typical constant {lambda} value. We also find that the fraction of AGN hosting galaxies in our sample strongly depends on galactic spin, increasing dramatically for decreasing {lambda}. For AGN host galaxies, we compute the mass of their supermassive black holes and find that this value tends to be higher for low spin galaxies, even at fixed luminosity, a result that could account, to a certain extent, for the spread on the luminosity-black-hole mass relation.

  14. Bilateral renal vein thrombosis and pulmonary embolism secondary to membranous glomerulonephritis treated with percutaneous catheter thrombectomy and localized thrombolytic therapy

    PubMed Central

    Janda, S. P.

    2010-01-01

    Renal vein thrombosis (RVT) is a rare event but is prevalent in patients with nephrotic syndrome. Bilateral RVT is even rarer. The literature is relatively sparse in terms of the management of RVT because of its rarity and consists of a few case reports and case series. We present a case with bilateral RVT complicated by a pulmonary embolism in a patient with membranous glomerulonephritis (MGN). A 19-year-old female presented with acute flank pain and worsening renal function after a couple of weeks in hospital while being treated with diuretics for anasarca secondary to MGN. Venography was used for diagnosis. The patient underwent percutaneous catheter thrombectomy and localized thrombolysis achieving resolution of pain and improvement of renal function. The patient was then anticoagulated for life with warfarin. PMID:21072156

  15. Combined optical coherence tomography and optical coherence elastography for glomerulonephritis classification

    NASA Astrophysics Data System (ADS)

    Liu, Chih-Hao; Du, Yong; Singh, Manmohan; Wu, Chen; Han, Zhaolong; Li, Jiasong; Mohammadzai, Qais; Raghunathan, Raksha; Hsu, Thomas; Noorani, Shezaan; Chang, Anthony; Mohan, Chandra; Larin, Kirill V.

    2016-03-01

    Acute Glomerulonephritis caused by anti-glomerular basement membrane disease has a high mortality due to delayed diagnosis. Thus, an accurate and early diagnosis is critical for preserving renal function. Currently, blood, urine, and tissue-based diagnoses can be time consuming, while ultrasound and CT imaging have relatively low spatial resolution. Optical coherence tomography (OCT) is a noninvasive imaging technique that provides superior spatial resolution (micron scale) as compared to ultrasound and CT. Pathological changes in tissue properties can be detected based on the optical metrics analyzed from the OCT signal, such as optical attenuation and speckle variance. Moreover, OCT does not rely on ionizing radiation as with CT imaging. In addition to structural changes, the elasticity of the kidney can significantly change due to nephritis. In this work, we utilized OCT to detect the difference in tissue properties between healthy and nephritic murine kidneys. Although OCT imaging could identify the diseased tissue, classification accuracy using only optical metrics was clinically inadequate. By combining optical metrics with elasticity, the classification accuracy improved from 76% to 95%. These results show that OCT combined with OCE can be potentially useful for nephritis detection.

  16. Outcome of glomerulonephritis in live-donor renal transplant recipients: A single-centre experience

    PubMed Central

    Akl, Ahmed Ibrahim; Adel, Hany; Rahim, Mona Abdel; Wafa, Ehab Wahba; Shokeir, Ahmed A.

    2015-01-01

    Objectives To investigate the frequency and risk factors affecting the incidence of post-transplantation glomerulonephritis (GN) and the impact of GN on the survival of the graft and the patient. Patients and methods Patients were classified based on histological findings into three groups. Graft survival was ascertained using the Kaplan–Meier method and significance calculated using log-rank tests. For multivariate analysis the Cox model was used. Results Transplant glomerulopathy was the most prevalent glomerular disease in our series followed by recurrent GN and lastly de novo GN. In all, 50% of the de novo GN group had diabetes. The worst graft outcomes were in the recurrent GN group (P = 0.044). Multivariate analysis revealed ageing of the graft and mammalian target of rapamycin (mTOR) immunosuppression as risk factors for development of GN. While, the age of the recipient and donor, anti-lymphocyte globulin induction therapy, and acute rejection were risk factors for poor graft outcomes. Conclusions GN is an important issue after transplantation. Tracking the incidence and progression of histological findings in the graft may help to guide proper management and improve graft outcome. PMID:26609451

  17. Mesangial Localization of Immune Complexes in Experimental Canine Adenovirus Glomerulonephritis

    PubMed Central

    Wright, N. G.; Morrison, W. I.; Thompson, H.; Cornwell, H. J. C.

    1974-01-01

    Each of a group of 14 dogs was infected experimentally by an intravenous dose of canine adenovirus calculated to allow survival until the initial stages of antibody production; the kidneys of infected dogs were examined during the period of 4-14 days after administration of virus. Proliferative glomerulonephritis with localization of IgG, C3 and viral antigen in mesangial regions was demonstrated. With the electron microscope, electron dense deposits were found scattered throughout the mesangium. There was proliferation of mesangial cells, infiltration into the glomerular tuft of polymorphonuclear leucocytes and, in some cases, focal glomerular necrosis with intracapsular and tubular haemorrhage. By means of an indirect immunofluorescence test, anti-viral antibody was detected in kidney eluates; anti-kidney antibody was not present. ImagesFigs. 5-8Figs. 9-10Figs. 1-4 PMID:4375485

  18. Fibrillary glomerulonephritis combined with chronic inflammatory demyelinating polyneuropathy

    PubMed Central

    Sung, Woo Kyung; Jeong, Jin Uk; Bang, Ki Tae; Shin, Jong Ho; Yoo, Ji Hyung; Kim, Nak Min; Park, Jun Hyung; Kim, Joo Heon

    2015-01-01

    A 58-yr-old man presented with leg edema and subacute weakness of his bilateral lower extremities. Urinary and serum immunoelectrophoresis revealed the presence of lambda-type Bence Jones proteins. He was ultimately diagnosed with monoclonal gammopathy of undetermined significance (MGUS). A renal biopsy specimen showed fibrillary glomerulonephritis (FGN), which was randomly arranged as 12–20 m nonbranching fibrils in the basement membranes. Immunofluorescence studies were negative for immunoglobulin (Ig)G, IgM, IgA, C3, and kappa light chains in the capillary walls and mesangial areas. A Congo red stain for amyloid was negative. Electromyography and nerve conduction velocity examinations results were compatible with the presence of demyelinating polyneuropathy. This case showed a rare combination of FGN, without Ig deposition, and MGUS combined with chronic inflammatory demyelinating polyneuropathy (CIDP). PMID:26484033

  19. Crescentic glomerulonephritis in a polar bear (Ursus maritimus).

    PubMed

    Baba, Hiroshi; Kudo, Tomoo; Makino, Yoshinori; Mochizuki, Yasumasa; Takagi, Takayo; Une, Yumi

    2013-11-01

    Spontaneous crescentic glomerulonephritis (CrGN) in animals has only been reported in dog and sheep. We report the pathological features of CrGN in a 17-year-old male polar bear that died due to renal failure. Histologically, the lesions were characterized by fibrocellular crescents, adhesion between Bowman's capsule and the glomerular capillary tuft and an increase in the mesangial matrix in glomeruli. The proliferating cells in the crescent were partly immunopositive for cytokeratin and intensely positive for vimentin, WT-1 and α-smooth muscle actin, suggesting they originated from parietal epithelial cells. Ultrastructually, thickening of the glomerular basement membrane and loss of epithelial cell foot processes were observed with electron-dense deposits. PMID:23856758

  20. Fibrillary glomerulonephritis combined with chronic inflammatory demyelinating polyneuropathy.

    PubMed

    Sung, Woo Kyung; Jeong, Jin Uk; Bang, Ki Tae; Shin, Jong Ho; Yoo, Ji Hyung; Kim, Nak Min; Park, Jun Hyung; Kim, Joo Heon

    2015-06-01

    A 58-yr-old man presented with leg edema and subacute weakness of his bilateral lower extremities. Urinary and serum immunoelectrophoresis revealed the presence of lambda-type Bence Jones proteins. He was ultimately diagnosed with monoclonal gammopathy of undetermined significance (MGUS). A renal biopsy specimen showed fibrillary glomerulonephritis (FGN), which was randomly arranged as 12-20 m nonbranching fibrils in the basement membranes. Immunofluorescence studies were negative for immunoglobulin (Ig)G, IgM, IgA, C3, and kappa light chains in the capillary walls and mesangial areas. A Congo red stain for amyloid was negative. Electromyography and nerve conduction velocity examinations results were compatible with the presence of demyelinating polyneuropathy. This case showed a rare combination of FGN, without Ig deposition, and MGUS combined with chronic inflammatory demyelinating polyneuropathy (CIDP). PMID:26484033

  1. [Rapidly progressive glomerulonephritis: a diagnostic and therapeutic emergency].

    PubMed

    Halfon, Matthieu; Teta, Daniel; Rotman, Samuel; Pruijm, Menno; Humbert, Antoine

    2014-02-26

    Rapidly progressive glomerulonephritis (RPG) is a rare clinical syndrome characterized by kidney damage that can lead to irreversible kidney failure. RPG can be caused by primary glomerular disease or can be part of a systemic autoimmune disorder. All RPG have a similar pathophysiology (proliferation of cells in Bowman's capsule and formation of crescents) and clinical evolution (rapidly progressive kidney failure with proteinuria and an active urine sediment). Immunosuppressive therapy and sometimes plasma exchanges are required. Overall- and kidney survival are closely linked to the blood creatinine level at presentation, the percentage of damaged glomeruli, and to the underlying cause. RPG is therefore a diagnostic and therapeutic emergency that needs quick referral to a nephrologist. PMID:24665657

  2. The nephrotic syndrome in a heifer due to glomerulonephritis.

    PubMed

    Wiseman, A; Spencer, A; Petrie, L

    1980-05-01

    An 18-month-old Friesian heifer, which was admitted in November with a history of weight loss, diarrhoea and submandibular oedema, was found to have an enlarged left kidney and a massive proteinuria. Laboratory investigations revealed that there was a marked hypoalbuminaemia and that the range and the proportions of the individual proteins in the urine were almost identical to those in the serum. Consequently, the nephrotic syndrome was diagnosed. On gross and histopathological examination of the kidneys, there was evidence of pyelonephritis. However, immunofluorescence studies revealed a striking diffuse deposition of immunoglobulin in a predominantly linear pattern along the glomerular basement membranes. Abnormalities of the basement membranes. Abnormalities of the basement membranes were seen on ultrastructural examination and evidence of a flomerular protein leak was detected but changes typical of immune-complex deposition were absent. The immunofluorescence findings suggested a diagnosis of glomerulonephritis mediated by antiglomerular basement membrane antibody. PMID:7414086

  3. Proliferative glomerulonephritis with monoclonal immunoglobulin in renal allografts

    PubMed Central

    Al-Rabadi, Laith; Francis, Jean M.; Henderson, Joel; Ghai, Sandeep

    2015-01-01

    Glomerulopathy due to dysproteinemia can have a wide spectrum of pathologic and clinical features based on specific characteristics of the abnormal protein and the response induced within the parenchymal tissue. Monoclonal immunoglobulin G (IgG) deposition can manifest as a different glomerular disease. Proliferative glomerulonephritis (GN) with monoclonal IgG deposits (PGNMID) is a unique entity mimicking immune complex GN that does not conform to any of those subtypes. IgG monoclonal granular deposition in the glomeruli with a pattern similar to immune complex disease suggested by C3 and C1q deposition should prompt consideration of PGNMID. Literature is scarce in terms of recurrence of disease in renal allografts. In this article we present the clinical–pathologic features of three cases of PGNMID in the renal allograft showing the variable course and manifestation of the disease. PMID:26613031

  4. White-blue pyelocalyceal cyst with hydrotic glomerulonephritis

    PubMed Central

    Chaurasia, Jai Kumar; Soni, Mayank; Ahmed, Murad; Naim, Mohammed

    2013-01-01

    A 5-month-old male infant presented with a 15 day history of distension of abdomen. On clinical examination, a soft lump was palpable in the left lumbar region. Radiological findings suggested an enlarged non-functional left kidney with ureteropelvic adhesive obstruction. The left renal mass was excised and submitted for histopathological examination. The excised renal mass was cystic with its wall partly white and partly blue. Gross and histopathological findings were diagnostic of a white-blue pyelocalyceal cyst with hydrotic glomerulonephritis. This entity needs to be differentiated from a large number of other cystic diseases of the kidney. Intrauterine screening and diagnosis may be significant for a possible early intrauterine uro-laparoscopic recanalisation of the pyeloureteral obstruction to save the affected kidney. PMID:24347451

  5. Proliferative glomerulonephritis with monoclonal immunoglobulin deposition disease: The utility of routine staining with immunoglobulin light chains

    PubMed Central

    Gowda, K. K.; Nada, R.; Ramachandran, R.; Joshi, K.; Tewari, R.; Kohli, H. S.; Jha, V.; Gupta, K. L.

    2015-01-01

    Proliferative glomerulonephritis occurring as a consequence of monoclonal glomerular deposits of IgG is uncommon. It is a form of renal involvement in monoclonal gammopathy that mimics immune complex glomerulonephritis. Here, we report the first series of proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) from the Indian subcontinent highlighting use of light chain immunofluorescence (IF) in routine renal biopsy interpretation. We retrieved 6 patients diagnosed as proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) out of 160 biopsies (3.7%) with membranoproliferative patterns over 5 1/2 years (2009–2014), one of whom had recurrence 6 months post-renal transplant. Four (67%) patients presented with rapidly progressive renal failure and two (33%) with nephrotic syndrome. None of these patients had overt multiple myeloma. The predominant histologic pattern was membranoproliferative with all the biopsies showing IgG3 Kappa deposits on IF. The deposits were primarily subendothelial on electron microscopy. PMID:26664209

  6. [Aplastic anemia combined with an autoimmune disease (eosinophilic fasciitis or glomerulonephritis)].

    PubMed

    Stebler, C; Tichelli, A; Gratwohl, A; Dazzi, H; Nissen, C; Steiger, U; Speck, B

    1991-06-01

    We describe 3 patients with aplastic anemia and an autoimmune disease. Two had eosinophilic fasciitis and 1 glomerulonephritis. In all patients both diseases were successfully treated by immunosuppressive therapy. Pathophysiological aspects of this association are discussed. PMID:1857945

  7. Proliferative glomerulonephritis with monoclonal immunoglobulin deposition disease: The utility of routine staining with immunoglobulin light chains.

    PubMed

    Gowda, K K; Nada, R; Ramachandran, R; Joshi, K; Tewari, R; Kohli, H S; Jha, V; Gupta, K L

    2015-01-01

    Proliferative glomerulonephritis occurring as a consequence of monoclonal glomerular deposits of IgG is uncommon. It is a form of renal involvement in monoclonal gammopathy that mimics immune complex glomerulonephritis. Here, we report the first series of proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) from the Indian subcontinent highlighting use of light chain immunofluorescence (IF) in routine renal biopsy interpretation. We retrieved 6 patients diagnosed as proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) out of 160 biopsies (3.7%) with membranoproliferative patterns over 5 1/2 years (2009-2014), one of whom had recurrence 6 months post-renal transplant. Four (67%) patients presented with rapidly progressive renal failure and two (33%) with nephrotic syndrome. None of these patients had overt multiple myeloma. The predominant histologic pattern was membranoproliferative with all the biopsies showing IgG3 Kappa deposits on IF. The deposits were primarily subendothelial on electron microscopy. PMID:26664209

  8. Non-thermal AGN models

    SciTech Connect

    Band, D.L.

    1986-12-01

    The infrared, optical and x-ray continua from radio quiet active galactic nuclei (AGN) are explained by a compact non-thermal source surrounding a thermal ultraviolet emitter, presumably the accretion disk around a supermassive black hole. The ultraviolet source is observed as the ''big blue bump.'' The flat (..cap alpha.. approx. = .7) hard x-ray spectrum results from the scattering of thermal ultraviolet photons by the flat, low energy end of an electron distribution ''broken'' by Compton losses; the infrared through soft x-ray continuum is the synchrotron radiation of the steep, high energy end of the electron distribution. Quantitative fits to specific AGN result in models which satisfy the variability constraints but require electron (re)acceleration throughout the source. 11 refs., 1 fig.

  9. Necrotizing ANCA-Positive Glomerulonephritis Secondary to Culture-Negative Endocarditis

    PubMed Central

    Van Haare Heijmeijer, Sophie; Wilmes, Dunja; Aydin, Selda; Clerckx, Caroline; Labriola, Laura

    2015-01-01

    Infective endocarditis (IE) and small-vessel vasculitis may have similar clinical features, including glomerulonephritis. Furthermore the association between IE and ANCA positivity is well documented, making differential diagnosis between IE- and ANCA-associated vasculitis particularly difficult, especially in case of culture-negative IE. We report on one patient with glomerulonephritis secondary to culture-negative IE caused by Bartonella henselae which illustrates this diagnostic difficulty. PMID:26819786

  10. Fundus changes in mesangiocapillary glomerulonephritis type II: clinical and fluorescein angiographic findings.

    PubMed Central

    Duvall-Young, J; Short, C D; Raines, M F; Gokal, R; Lawler, W

    1989-01-01

    Previously we have demonstrated a deposit in Bruch's membrane in a single case of mesangiocapillary glomerulonephritis type II. We studied a group of patients with this disease and described extensive clinical and fluorescein angiographic abnormalities, which were in marked contrast to the findings in a group of patients with other forms of glomerulonephritis. This finding contributes to our understanding of the pathophysiology of the complex of the retinal pigment epithelium, Bruch's membrane, and choriocapillaris. Images PMID:2605144

  11. Radio Loud AGNs are Mergers

    NASA Astrophysics Data System (ADS)

    Chiaberge, Marco; Gilli, Roberto; Lotz, Jennifer M.; Norman, Colin

    2015-06-01

    We measure the merger fraction of Type 2 radio-loud and radio-quiet active galactic nuclei (AGNs) at z\\gt 1 using new samples. The objects have Hubble Space Telescope (HST) images taken with Wide Field Camera 3 (WFC3) in the IR channel. These samples are compared to the 3CR sample of radio galaxies at z\\gt 1 and to a sample of non-active galaxies. We also consider lower redshift radio galaxies with HST observations and previous generation instruments (NICMOS and WFPC2). The full sample spans an unprecedented range in both redshift and AGN luminosity. We perform statistical tests to determine whether the different samples are differently associated with mergers. We find that all (92%-14%+8%) radio-loud galaxies at z\\gt 1 are associated with recent or ongoing merger events. Among the radio-loud population there is no evidence for any dependence of the merger fraction on either redshift or AGN power. For the matched radio-quiet samples, only 38%-15+16 are merging systems. The merger fraction for the sample of non-active galaxies at z\\gt 1 is indistinguishable from radio-quiet objects. This is strong evidence that mergers are the triggering mechanism for the radio-loud AGN phenomenon and the launching of relativistic jets from supermassive black holes (SMBHs). We speculate that major black hole (BH)–BH mergers play a major role in spinning up the central SMBHs in these objects.

  12. Comparing Simulations of AGN Feedback

    NASA Astrophysics Data System (ADS)

    Richardson, Mark L. A.; Scannapieco, Evan; Devriendt, Julien; Slyz, Adrianne; Thacker, Robert J.; Dubois, Yohan; Wurster, James; Silk, Joseph

    2016-07-01

    We perform adaptive mesh refinement (AMR) and smoothed particle hydrodynamics (SPH) cosmological zoom simulations of a region around a forming galaxy cluster, comparing the ability of the methods to handle successively more complex baryonic physics. In the simplest, non-radiative case, the two methods are in good agreement with each other, but the SPH simulations generate central cores with slightly lower entropies and virial shocks at slightly larger radii, consistent with what has been seen in previous studies. The inclusion of radiative cooling, star formation, and stellar feedback leads to much larger differences between the two methods. Most dramatically, at z=5, rapid cooling in the AMR case moves the accretion shock to well within the virial radius, while this shock remains near the virial radius in the SPH case, due to excess heating, coupled with poorer capturing of the shock width. On the other hand, the addition of feedback from active galactic nuclei (AGNs) to the simulations results in much better agreement between the methods. For our AGN model, both simulations display halo gas entropies of 100 keV cm2, similar decrements in the star formation rate, and a drop in the halo baryon content of roughly 30%. This is consistent with the AGN growth being self-regulated, regardless of the numerical method. However, the simulations with AGN feedback continue to differ in aspects that are not self-regulated, such that in SPH a larger volume of gas is impacted by feedback, and the cluster still has a lower entropy central core.

  13. The Importance of Winds for AGN Feedback

    NASA Astrophysics Data System (ADS)

    Crenshaw, D. M.; Kraemer, S. B.; Schmitt, H. R.; Fischer, T. C.; Gagne, J.

    2014-01-01

    Active galactic nuclei (AGN) are fed by accretion of matter onto supermassive black holes (SMBHs), generating huge amounts of radiation from very small volumes. AGN also provide feedback to their environments via mass outflows of ionized gas, which could play a critical role in the formation of large-scale structure in the early Universe, chemical enrichment of the intergalactic medium, and self-regulation of SMBH and galactic bulge growth. We provide an update on our research on the winds in nearby moderate-luminosity AGN, In particular, we concentrate on winds that occur on relatively large scales (hundreds of parsecs) that are revealed through spatially resolved HST spectra of emission-line gas in the narrow line regions (NLRs) of nearby AGN. We discuss the techniques for measuring the mass outflow rates and kinetic luminosities of these AGN winds and gauge their importance for providing significant AGN feedback.

  14. New insights into AGN coronae

    NASA Astrophysics Data System (ADS)

    Lohfink, Anne; Fabian, Andrew C.; Malzac, Julien; Belmont, Renaud; Buisson, Douglas

    2016-04-01

    Active galactic nuclei (AGN) are some of the most energetic sources of radiation in the Universe. The conversion of gravitational energy into radiation is thought to take place in an accretion disk/corona system just outside the black hole. In this system thermal, UV/optical photons from the accretion disk are upscattered in a corona of hot electrons situated above the accretion disk producing X-rays. The nature of this Comptonizing corona remains a key open question in AGN physics. The NuSTAR satellite provides the opportunity to study the Comptonization spectrum produced by the corona in great detail. In our talk we will show some key results from these new studies of the Comptonization spectrum. We explore how, together with our growing knowledge of coronal sizes, we are able to draw first conclusions about the physics taking place in the corona. We find evidence for coronae to be hot and radiatively compact, putting them close to the boundary of the region in the compactness-temperature diagram which is forbidden due to runaway pair production. This suggests that pair production and annihilation are essential ingredients in the coronae of AGN and that they control the coronal temperature and shape of the observed spectra.

  15. Probing AGN Unification with galaxy neighbours: pitfalls and prospects

    NASA Astrophysics Data System (ADS)

    Villarroel, B.

    2015-09-01

    Statistical tests of AGN unification harbour many caveats. One way of constraining the validity of the AGN unification is through studies of close neighbours to Type-1 and Type-2 AGN. Examining thousands of AGN- galaxy pairs from the Sloan Digital Sky Survey Data Release 7 and the Galaxy Zoo project, we found that Type-2 AGN appear to reside in more star-forming environments than Type-1 AGN.

  16. CXCR3 Is Involved in Tubulointerstitial Injury in Human Glomerulonephritis

    PubMed Central

    Segerer, Stephan; Banas, Bernhard; Wörnle, Markus; Schmid, Holger; Cohen, Clemens D.; Kretzler, Matthias; Mack, Matthias; Kiss, Eva; Nelson, Peter J.; Schlöndorff, Detlef; Gröne, Hermann-Josef

    2004-01-01

    Chemokines play pivotal roles in the recruitment of inflammatory cells into the kidney. The chemokine receptors CXCR3 and CCR5 are expressed on activated T lymphocytes, and expression of CXCR3 by mesangial cells has been suggested. Detailed description of CXCR3 expression might form a rational basis for use as a diagnostic marker and for therapeutic CXCR3 targeting in human glomerulonephritis. We studied the expression of CXCR3 in renal biopsies by immunohistochemistry (n = 45), and real time RT-PCR (n = 78). Biopsies were from patients with IgA nephropathy, lupus nephritis, and membranoproliferative glomerulonephritis. Furthermore, cultured human mesangial cells (HMC) were studied for CXCR3 expression, and for functional responses to the ligands CXCL10/IP-10 and CXCL9/Mig. CXCR3-positive cells were rarely found in glomerular tufts, but formed a major part of the tubulointerstitial infiltrates. Consistently, CXCR3 mRNA expression was too low to be quantified in glomerular compartments, and was not detectable in HMC. The published staining for CXCR3 of mesangial cells could be traced to cross-reactivity of an antibody for CXCR3 with a potentially related chemokine receptor as revealed by FACS analysis. Despite an absence of CXCR3 expression, mesangial cells reacted to CXCR3 ligands by proliferation and migration, which was blocked by pertussis toxin but not by an anti-CXCR3 antibody. These results indicate that HMC do not express the classical CXCR3, but may potentially express a related receptor with shared ligand specificity. By immunohistochemistry the number of CXCR3-positive cells, mainly interstitial T cells, correlated with renal function, proteinuria, and percentage of globally sclerosed glomeruli. A significant morphological and numerical correlation between CD3, CXCR3, and CCR5-positive cells indicated a CXCR3/CCR5 double-positive T cell population. No apparent difference in the CXCR3 expression pattern was found between disease entities. CXCR3 expression

  17. SWIFT BAT Survey of AGN

    NASA Technical Reports Server (NTRS)

    Tueller, J.; Mushotzky, R. F.; Barthelmy, S.; Cannizzo, J. K.; Gehrels, N.; Markwardt, C. B.; Skinner, G. K.; Winter, L. M.

    2008-01-01

    We present the results1 of the analysis of the first 9 months of data of the Swift BAT survey of AGN in the 14-195 keV band. Using archival X-ray data or follow-up Swift XRT observations, we have identified 129 (103 AGN) of 130 objects detected at [b] > 15deg and with significance > 4.8-delta. One source remains unidentified. These same X-ray data have allowed measurement of the X-ray properties of the objects. We fit a power law to the logN - log S distribution, and find the slope to be 1.42+/-0.14. Characterizing the differential luminosity function data as a broken power law, we find a break luminosity logL*(ergs/s)= 43.85+/-0.26. We obtain a mean photon index 1.98 in the 14-195 keV band, with an rms spread of 0.27. Integration of our luminosity function gives a local volume density of AGN above 10(exp 41) erg/s of 2.4x10(exp -3) Mpc(sup -3), which is about 10% of the total luminous local galaxy density above M* = -19.75. We have obtained X-ray spectra from the literature and from Swift XRT follow-up observations. These show that the distribution of log nH is essentially flat from nH = 10(exp 20)/sq cm to 10(exp 24)/sq cm, with 50% of the objects having column densities of less than 10(exp 22)/sq cm. BAT Seyfert galaxies have a median redshift of 0.03, a maximum log luminosity of 45.1, and approximately half have log nH > 22.

  18. AGN Winds and Blazar Phenomenology

    NASA Technical Reports Server (NTRS)

    Kazanas, Demos

    2012-01-01

    The launch of {\\em Fermi} produced a significant number of AGN detections to allow statistical treatment of their properties. One of the first such systematics was the "Blazar Divide" in FSRQs and BL Lacs according to their gamma-ray spectral index and luminosity. Further data accumulation indicated this separation to be less clear than thought before. An MHD wind model which can model successfully the Seyfert X-ray absorber properties provides the vestiges of an account of the observed blazar classification. We propose to employ this model to model in detail the broad band blazar spectra and their statistical properties in terms of the physical parameters of these MHD winds.

  19. AGN Zoo and Classifications of Active Galaxies

    NASA Astrophysics Data System (ADS)

    Mickaelian, Areg M.

    2015-07-01

    We review the variety of Active Galactic Nuclei (AGN) classes (so-called "AGN zoo") and classification schemes of galaxies by activity types based on their optical emission-line spectrum, as well as other parameters and other than optical wavelength ranges. A historical overview of discoveries of various types of active galaxies is given, including Seyfert galaxies, radio galaxies, QSOs, BL Lacertae objects, Starbursts, LINERs, etc. Various kinds of AGN diagnostics are discussed. All known AGN types and subtypes are presented and described to have a homogeneous classification scheme based on the optical emission-line spectra and in many cases, also other parameters. Problems connected with accurate classifications and open questions related to AGN and their classes are discussed and summarized.

  20. Glomerulonephritis in a ferret with feline coronavirus infection.

    PubMed

    Fujii, Yuta; Tochitani, Tomoaki; Kouchi, Mami; Matsumoto, Izumi; Yamada, Toru; Funabashi, Hitoshi

    2015-09-01

    A male domestic ferret (Mustela putorius furo), which was purchased from outside of Japan at 13 weeks of age, was euthanized at 18 months of age because of poor health. At autopsy, the liver, spleen, and mesenteric lymph node were enlarged, and white foci were observed on the outer surface of the liver. The outer surface of the mesenteric lymph node was dark red. Histologically, granulomas were observed in the liver, spleen, bone marrow, and lymph nodes, composed mainly of aggregated epithelioid macrophages, some of which were positive to an anti-feline coronavirus (FCoV; Alphacoronavirus 1) antibody in immunohistochemistry. Mesangioproliferative glomerulonephritis was observed, and periodic acid-Schiff-positive deposits were observed along glomerular capillary walls. These deposits stained pale red with periodic acid-methenamine silver stain and red with Masson trichrome stain, and were also observed in the mesangial matrix. In affected glomeruli, glomerular capillary walls and mesangial areas were positive for anti-ferret immunoglobulin G. By electron microscopy, subepithelial and mesangial electron-dense deposits were observed consistent with immune complex deposition. The deposition of immune complexes may have been associated with FCoV infection. PMID:26319601

  1. Sjögren Syndrome and Cryoglobulinemic Glomerulonephritis.

    PubMed

    Anand, Ananya; Krishna, Gopal G; Sibley, Richard K; Kambham, Neeraja

    2015-09-01

    We report the case of a 53-year-old woman with Sjögren syndrome and cryoglobulinemia. The patient presented with nephrotic syndrome, hematuria, and reduced estimated glomerular filtration rate. The kidney biopsy revealed diffuse endocapillary proliferation and leukocyte exudation with focal intraluminal hyaline thrombi, prominent tubulointerstitial inflammation, and vasculitis. Diffuse granular mesangial and segmental to global capillary wall staining was observed on immunofluorescence with antisera to C3 and immunoglobulin M (IgM), with less intense staining indicative of IgG and κ and λ light chains. A biopsy diagnosis of Sjögren syndrome-related cryoglobulinemic membranoproliferative glomerulonephritis and vasculitis was rendered. Subsequent investigations revealed the presence of circulating type II cryoglobulins with cryocrit of 9%. Although rare, Sjögren syndrome is the most common cause of non-hepatitis C virus-related mixed cryoglobulinemia. We discuss the possible pathogenic mechanisms involved in the development of mixed cryoglobulinemia and its evolution to lymphoma, as best described in the setting of hepatitis C virus infection. Although the specific antigen involved is unknown, it is likely that the mixed cryoglobulinemia in Sjögren syndrome is triggered by the long-term B-cell stimulation, resulting in clonal proliferation of B cells. Additional chromosomal aberrations and cytokine milieu alterations, as seen in hepatitis C virus infection, may result in prolonged B-cell survival and progression to non-Hodgkin lymphoma. PMID:25661680

  2. What is new in the management of rapidly progressive glomerulonephritis?

    PubMed

    Greenhall, George H B; Salama, Alan D

    2015-04-01

    Rapidly progressive glomerulonephritis (RPGN) results from severe crescentic damage to glomeruli and leads to irreversible kidney failure if not diagnosed and managed in a timely fashion. Traditional treatment has relied on glucocorticoids and cyclophosphamide, with additional plasmapheresis for certain conditions. Here we describe updates in the management of RPGN, according to the underlying renal pathology. However, there remains a paucity of trials that have enrolled patients with more advanced renal disease, dialysis dependence or with RPGN, and we are therefore still reliant on extrapolation of data from studies of patients with a less severe form of disease. In addition, reporting bias results in publication of cases or cohorts showing benefit for newer agents in advanced disease or RPGN, but it remains unclear how many unsuccessful outcomes in these circumstances take place. Since clinical trials specifically in RPGN are unlikely, use of biologic registries or combination of sufficient sized cohort series may provide indications of benefit outside of a clinical trial setting and should be encouraged, in order to provide some evidence for the efficacy of therapeutic regimens in RPGN and advanced renal disease. PMID:25815169

  3. Incidence of post-transplant glomerulonephritis and its impact on graft outcome

    PubMed Central

    An, Jung Nam; Lee, Jung Pyo; Oh, Yun Jung; Oh, Yun Kyu; Ha, Jong-won; Chae, Dong-Wan; Kim, Yon Su; Lim, Chun Soo

    2012-01-01

    Background Herein, the significance of post-transplant glomerulonephritis (PTGN) has been revisited to investigate whether PTGN induces allograft failure. The aim of this study was to identify the incidence of PTGN and its association with allograft failure, as well as to analyze the risk factors for PTGN. Methods Among the 996 Korean patients who underwent kidney transplantation in a multicenter cohort from 1995 to 2010, 764 patients were enrolled in this study. Results The incidence rate of PTGN was 9.7% and 17.0% at 5 and 10 years of follow-up, respectively. PTGN was diagnosed in 17.8% of the recipients with results of biopsy tests or clinical diagnosis identifying glomerular diseases as the underlying cause, compared with 0.0%, 4.4%, 4.9%, 5.5%, and 5.7% of the recipients with renal vascular diseases, renal interstitial diseases/pyelonephritis/uropathy, diabetic renal disease, hereditary renal diseases, and diseases with unknown etiologies, respectively. Allograft survival was significantly decreased in patients with PTGN. PTGN was associated with a fourfold increase in graft failure with a hazard ratio of 7.11 for both acute rejection and PTGN. Results of the risk factor analysis for PTGN revealed that the underlying glomerular renal diseases and treatment methods using drugs such as tacrolimus and basiliximab significantly increased PTGN development, after adjusting for other risk factors. Conclusion We conclude that PTGN is strongly associated with poor kidney allograft survival. Therefore, optimal management of recurrent or de novo GN should be the critical focus of post-transplant care. PMID:26889425

  4. The 60-month all-sky BAT Survey of AGN and the Anisotropy of Nearby AGN

    SciTech Connect

    Ajello, M.; Alexander, D.M.; Greiner, J.; Madejski, G.M.; Gehrels, N.; Burlon, D.; /Garching, Max Planck Inst., MPE

    2012-04-02

    Surveys above 10 keV represent one of the the best resources to provide an unbiased census of the population of Active Galactic Nuclei (AGN). We present the results of 60 months of observation of the hard X-ray sky with Swift/BAT. In this timeframe, BAT detected (in the 15-55 keV band) 720 sources in an all-sky survey of which 428 are associated with AGN, most of which are nearby. Our sample has negligible incompleteness and statistics a factor of {approx}2 larger over similarly complete sets of AGN. Our sample contains (at least) 15 bona-fide Compton-thick AGN and 3 likely candidates. Compton-thick AGN represent a {approx}5% of AGN samples detected above 15 keV. We use the BAT dataset to refine the determination of the LogN-LogS of AGN which is extremely important, now that NuSTAR prepares for launch, towards assessing the AGN contribution to the cosmic X-ray background. We show that the LogN-LogS of AGN selected above 10 keV is now established to a {approx}10% precision. We derive the luminosity function of Compton-thick AGN and measure a space density of 7.9{sub -2.9}{sup +4.1} x 10{sup -5} Mpc{sup -3} for objects with a de-absorbed luminosity larger than 2 x 10{sup 42} erg s{sup -1}. As the BAT AGN are all mostly local, they allow us to investigate the spatial distribution of AGN in the nearby Universe regardless of absorption. We find concentrations of AGN that coincide spatially with the largest congregations of matter in the local ({le} 85 Mpc) Universe. There is some evidence that the fraction of Seyfert 2 objects is larger than average in the direction of these dense regions.

  5. Understanding the complement-mediated glomerular diseases: focus on membranoproliferative glomerulonephritis and C3 glomerulopathies.

    PubMed

    Lionaki, Sophia; Gakiopoulou, Hara; Boletis, John N

    2016-09-01

    An enhanced understanding of the role of complement in the pathogenesis of membranoproliferative glomerulonephritis has led to reclassification of the latter into immunoglobulin-mediated and non-immunoglobulin-mediated disease. The new classification schema resulted in improved diagnostic clinical algorithms, while it brought into light again the diseases, which are characterized by the presence of glomerular deposits, composed predominantly by C3, in the absence of significant amounts of immunoglobulins in renal biopsy, namely, C3 glomerulopathies (dense deposit disease and C3 glomerulonephritis). Despite the lack of randomized controlled trials following the advances in the understanding of the pathogenetic pathways involved in membranoproliferative glomerulonephritis, it is important that the new mechanistic approach has opened new roads for the exploration and discovery of targeted therapies. PMID:27356907

  6. Streptococcal pyrogenic exotoxin B antibodies in a mouse model of glomerulonephritis.

    PubMed

    Luo, Y-H; Kuo, C-F; Huang, K-J; Wu, J-J; Lei, H-Y; Lin, M T; Chuang, W-J; Liu, C-C; Lin, C-F; Lin, Y-S

    2007-09-01

    Streptococcal pyrogenic exotoxin B is an extracellular cysteine protease. Only nephritis-associated strains of group A streptococci secrete this protease and this may be involved in the pathogenesis of post-streptococcal glomerulonephritis. Mice were actively immunized with a recombinant protease inactive exotoxin B mutant or passively immunized with exotoxin B antibody. Characteristics of glomerulonephritis were measured using histology, immunoglobulin deposition, complement activation, cell infiltration, and proteinuria. None of the mice given bovine serum albumin or exotoxin A as controls showed any marked changes. Immunoglobulin deposition, complement activation, and leukocyte infiltration occurred only in the glomeruli of exotoxin B-hyperimmunized mice. One particular anti-exotoxin B monoclonal antibody, 10G, was cross-reactive with kidney endothelial cells and it caused kidney injury and proteinuria when infused into mice. This cross-reactivity may be involved in the pathogenesis of glomerulonephritis following group A streptococcal infection. PMID:17637712

  7. [The function of the hypophyseal-gonadal system in different variants of glomerulonephritis in children].

    PubMed

    Korovina, N A; Gavriushova, L P; Ametov, A S; Tvorogova, T M; Mumladze, E B; Toritsina, L K

    1990-01-01

    A total of 28 children with different varieties of glomerulonephritis were examined for the pituitary-gonadal system (PGS). The examination included measurements of follicle-stimulating and luteinizing hormones, prolactin, estradiol, progesterone and testosterone. To define standards of the content of the hormones under study, 45 children of the control group were examined. The relationship was analyzed between the content of hormones and the disease activity and gravity. The most active phase of glomerulonephritis was characterized by maximal alterations in the content of pituitary and gonadal hormones. The content of the latter ones appeared to be considerably changed in patients with the mixed pattern of glomerulonephritis, attesting to profound functional derangements in the PGS. The intensity of those derangements was determined by the severity of the pathological process. PMID:2259596

  8. Compton Thick AGN in the COSMOS field

    NASA Astrophysics Data System (ADS)

    Lanzuisi, Giorgio; Cosmos Collaboration

    2015-09-01

    I will present the results we published in a couple of recent papers (Lanzuisi et al. 2015, A&A 573A 137, Lanzuisi et al. 2015, arXiv 1505.01153) on the properties of X-ray selected Compton Thick (CT, NH>10^24 cm^-2) AGN, in the COSMOS survey. We exploited the rich multi-wavelength dataset available in this field, to show that CT AGN tend to harbor smaller, rapidly growing SMBH with respect to unobscured AGN, and have a higher chance of being hosted by star-forming, merging and post-merger systems.We also demonstrated the detectability of even more heavily obscured AGN (NH>10^25 cm^-2), thanks to a truly multi-wavelength approach in the same field. The extreme source detected in this way shows strong evidences of ongoing powerful AGN feedback, detected as blue-shifted wings of high ionization optical emission lines such as [NeV] and [FeVII], as well as of the [OIII] emission line.The results obtained from these works point toward a scenario in which highly obscured AGN occupy a peculiar place in the galaxy-AGN co-evolution process, in which both the host and the SMBH rapidly evolve toward the local relations.We will also present estimates on the detectability of such extreme sources up to redshift ~6-7 with Athena. Combining the most up to date models for the Luminosity Function of CT AGN at high z, aggressive data analysis techniques on faint sources, and the current Athena survey design, we demonstrate that we will detect, and recognize as such, a small (few to ten) but incredibly valuable sample of CT AGN at such high redshift.

  9. Structural characterization of the mesangial cell type IV collagenase and enhanced expression in a model of immune complex-mediated glomerulonephritis.

    PubMed Central

    Lovett, D. H.; Johnson, R. J.; Marti, H. P.; Martin, J.; Davies, M.; Couser, W. G.

    1992-01-01

    Secretion of glomerular cell-derived matrix metalloproteinases (MMPs) and their specific inhibitors, TIMP-1,2, may play an important role in the turnover of the glomerular extracellular matrix under basal and pathologic conditions. A 66-68 kd MMP secreted by cultured mesangial cells (MC) with activity against Type IV collagen and gelatin was purified and shown by amino-acid sequence analysis to be identical with a Type IV collagenase/gelatinase secreted by certain transformed tumor cell lines. The expression of the mesangial MMP in vivo was limited within the kidney to a small subset of the intrinsic glomerular mesangial cell population. After induction of acute anti-Thy 1.1 glomerulonephritis, there was a large increment in the number of Type IV collagenase-secreting MC, temporally coincident with the development of mesangial hypercellularity. The expression of the MMP inhibitor protein, TIMP-1, was not changed over this period. Ultrastructural studies localized the mesangial MMP to areas of evolving mesangiolysis and at sites of glomerular basement membrane disruption. Enhanced expression of the mesangial cell-derived Type IV collagenase may contribute to the evolution of glomerular injury in this model of immune complex-mediated glomerulonephritis or may be involved in the extensive matrix remodeling process that accompanies this form of glomerular injury. Images Figure 2 Figure 3 Figure 5 Figure 4 Figure 6 Figure 7 Figure 8 and Figure 9 Figure 10 Figure 11 Figure 12 PMID:1321565

  10. Glomerulonephritis-induced changes in kidney gene expression in rats

    PubMed Central

    Pavkovic, Mira; Riefke, Björn; Frisk, Anna-Lena; Gröticke, Ina; Ellinger-Ziegelbauer, Heidrun

    2015-01-01

    We investigated a glomerulonephritis (GN) model in rats induced by nephrotoxic serum (NTS) which contains antibodies against the glomerular basement membrane (GBM). The anti-GBM GN model in rats is widely used since its biochemical and histopathological characteristics are similar to crescentic nephritis and Goodpasture's disease in humans (Pusey, 2003[2]). Male Wistar Kyoto (WKY) and Sprague–Dawley (SD) rats were dosed once with 1, 2.5 and 5 ml/kg nephrotoxic serum (NTS) or 1.5 and 5 ml/kg NTS, respectively. GN and tubular damage were observed histopathologically in all treated rats after 14 days. To obtain insight into molecular processes during GN pathogenesis, mRNA expression was investigated in WKY and SD kidneys using Affymetrix's GeneChip Rat genome 230_2.0 arrays (GSE64265). The immunopathological processes during GN are still not fully understood and likely involve both innate and adaptive immunity. In the present study, several hundred mRNAs were found deregulated, which functionally were mostly associated with inflammation and regeneration. The β-chain of the major histocompatibility complex class II RT1.B (Rt1-Bb) and complement component 6 (C6) were identified as two mRNAs differentially expressed between WKY and SD rat strains which could be related to known different susceptibilities to NTS of different rat strains; both were increased in WKY and decreased in SD rats (Pavkovic et al., 2015 [1]). Increased Rt1-Bb expression in WKY rats could indicate a stronger and more persistent cellular reaction of the adaptive immune system in this strain, in line with findings indicating adaptive immune reactions during GN. The complement cascade is also known to be essential for GN development, especially terminal cascade products like C6. PMID:26697341

  11. Immune complex erythrocyte complement receptor interactions in vivo during induction of glomerulonephritis in nonhuman primates

    SciTech Connect

    Birmingham, D.J.; Hebert, L.A.; Cosio, F.G.; VanAman, M.E. )

    1990-08-01

    Multiple lines of evidence indicate that the erythrocyte complement receptor (E-CR) system, which is unique to the primate, may play an important role in the clearing of immune complexes (ICs) from the circulation. However, all previous investigations of IC/E-CR interactions in vivo have involved the study of small amounts of preformed or passively formed ICs interacting with E-CR that were numerically in vast excess. The present study was undertaken to assess IC/E-CR interactions under conditions in which large amounts of ICs were formed in the circulation, amounts that when sustained for several weeks by daily intravenous administration of antigen resulted in the development of active glomerulonephritis. Twelve cynomolgus monkeys with E-CR levels ranging from 25 to 5000 mean CRs per erythrocyte (CR/E) were actively immunized to BGG, and 6 to 12 weeks later they were studied first at low levels of IC formation in vivo and then at high levels of IC formation in vivo (H-Protocol experiments, mean 125I-labeled BGG dose 4.9 mg/kg given over 10 minutes, a state approximating antigen-antibody equivalence). Cynomolgus monkeys with fewer than 100 CR/E showed no evidence of binding of ICs to erythrocytes with either low-dose or high-dose 125I-labeled BGG. However, cynomolgus monkeys with greater than 450 CR/E showed significant binding of ICs to erythrocytes: mean peak binding of 125I-labeled BGG to erythrocytes was 22.1% +/- 1.1% in the L-Protocol experiments and 33.4% +/- 8.0% in the H-Protocol experiments. During H-Protocol experiments, mean CR/E, measured by using a monoclonal anti-human CR1 antibody, decreased acutely, with recovery of E-CR levels within the next 24 to 72 hours. The acute decrease in E-CR levels could not be accounted for by occupancy of E-CR by ICs or by change in hematocrit.

  12. Toward a Unified AGN Structure

    NASA Technical Reports Server (NTRS)

    Kazanas, Demosthenes; Fukumura, Keigo; Shrader, Chris; Behar, Ehud; Contopoulosa, Ioannis

    2012-01-01

    We present a unified model for the structure and appearance of accretion powered sources across their entire luminosity range from galactic X-ray binaries (XRB) to luminous quasars, with emphasis on AG N and their phenomenology. Central to this model is the notion of MHD winds launched by the accretion disks that power these objects. These winds provide the matter that manifests as blueshifted absorption features in the UV and X-ray spectra of a large fraction of these sources; furthermore, their density distribution in the poloidal plane determines their "appearance" (i.e. the column and velocity structure of these absorption features and the obscuration of the continuum source) as a function of the observer inclination angle (a feature to which INTEGRAL has made significant contributions). This work focuses on just the broadest characteristics of these objects; nonetheless, it provides scaling laws that allow one to reproduce within this model the properties of objects extending in luminosity from luminous quasars to XRBs. Our general conclusion is that the AGN phenomenology can be accounted for in terms of three parameters: The wind maSS flux in units of the Eddington value, m(dot), the observers' inclination angle Theta and the logarithmic slope between the 0/UV and X-ray fluxes alpha(sub ox); however because of a correlation between alpha(sub ox) and UV luminosity the number of significant parameters is two. The AGN correlations implied by this model appear to extend to and consistent with the XRB phenomenology, suggesting the presence of a truly unified underlying structure for accretion powered sources.

  13. Preferential effectiveness of cyclosporin in patients receiving kidney transplants after glomerulonephritis.

    PubMed

    Cats, S; Terasaki, P I; Perdue, S; Mickey, M R

    1985-03-01

    Glomerulonephritis patients transplanted with cadaver kidneys had a significantly higher one-year graft survival when immunosuppressed with cyclosporin rather than standard therapy (80% versus 59%, p less than 10(-5]. For nephrosclerosis patients the corresponding rates were 70% and 59% (p greater than 0.05); and in those with antecedent diabetes mellitus, polycystic kidney, and pyelonephritis the differences were negligible. In glomerulonephritis patients, but not in the other groups, cyclosporin was additive to the effect of transfusions and of HLA-A, B and HLA-Dr matching. PMID:2857855

  14. Influenza vaccination induced leukocytoclastic vasculitis and pauci-immune crescentic glomerulonephritis.

    PubMed

    Yanai-Berar, N; Ben-Itzhak, O; Gree, J; Nakhoul, F

    2002-09-01

    Influenza vaccination is a widely accepted practice, particularly among the elderly and high-risk individuals. Minor and transitory side effects following the vaccination are common, while systemic complications are infrequently reported. We describe here a case of a patient who presented to the emergency room with arthralgia, myalgias and purpura, following influenza vaccination. Necrotizing vasculitis associated with pauci-immune glomerulonephritis was observed on kidney biopsy. With increasing use of influenza vaccination, attention should be drawn to the possible expression of systemic adverse effects such as vasculitis and glomerulonephritis. PMID:12356192

  15. Spectral Energy Distributions of Type 1 AGNs

    NASA Astrophysics Data System (ADS)

    Hao, Heng

    The spectral energy distributions (SEDs) of active galactic nuclei (AGNs) are essential to understand the physics of supermassive black holes (SMBHs) and their host galaxies. This thesis present a detailed study of AGN SED shapes in the optical-near infrared bands (0.3--3microm) for 413 X-ray selected Type 1 AGNs from the XMM-COSMOS Survey. We define a useful near-IR/optical index-index ('color-color') diagram to investigate the mixture of AGN continuum, host galaxy and reddening contributions. We found that ˜90% of the AGNs lie on mixing curves between the Elvis et al. (1994) mean AGN SED (E94) and a host galaxy, with only the modest reddening [E(B-V)=0.1--0.2] expected in type 1 AGNs. Lower luminosity and Eddington ratio objects have more host galaxy, as expected. The E94 template is remarkably good in describing the SED shape in the 0.3--3microrn decade of the spectrum over a range of 3.2 dex in LOPT, 2.7 dex in L/LEdd, and for redshifts up to 3. The AGN phenomenon is thus insensitive to absolute or relative accretion rate and to cosmic time. However, 10% of the AGNs are inconsistent with any AGN+host+reddening mix. These AGNs have weak or non-existent near-IR bumps, suggesting a lack of the hot dust characteristic of AGNs. The fraction of these hot-dust-poor AGNs evolves with redshift from 6% at low redshift (z < 2) to 20% at moderately high redshift (2 < z < 3.5). A similar fraction of HDP quasars are found in the Elvis et al. 1994 (BQS) and Richards et al. 2006 (SDSS) samples. The 1--3microm emission of the HDP quasars is a factor 2--4 smaller than the typical E94 AGN SED. The implied torus covering factor is 2%--29%, well below the 75% required by unified models. The weak hot dust emission seems to expose an extension of the accretion disk continuum in some of AGNs. For these, we estimate the outer edge of their accretion disks to lie at ˜104 Schwarzschild radii, more than ten times the gravitational stability radii. Either the host-dust is destroyed

  16. Low luminosity AGNs in the local universe

    NASA Astrophysics Data System (ADS)

    Ikiz, Tuba; Peletier, Reynier F.; Yesilyaprak, Cahit

    2016-04-01

    Galaxies are known to contain black holes (e.g. Ferrarese & Merritt 2000), whose mass correlates with the mass of their bulge. A fraction of them also has an Active Galactic Nucleus (AGN), showing excess emission thought to be due to accretion of mass by the supermassive black hole at the center of the galaxy. It is thought that AGNs play a very important role during the formation of galaxies by creating large outflows that stop star formation in the galaxy (see e.g. Kormendy & Ho 2013). The aim is to detect the fraction of Low Luminosity Active Galactic Nucleus (LLAGN) in the nearby Universe. At present, they are typically found using optical spectroscopy (e.g. Kauffmann, Heckman et al. 2003), who discuss the influence of the AGN on the host galaxy and vice versa. However, optical spectra are seriously affected by extinction in these generally very dusty objects, and therefore can only give us partial information about the AGN. I used a newly-found method, and apply it to the S4G sample, a large, complete, sample of nearby galaxies, which I am studying in detail with a large collaboration, to detect the fraction of low luminosity AGNs, and to better understand the relation between AGNs and their host galaxy which is thought to be crucial for their formation.

  17. A New Catalog of Type 1 AGNs and its Implications on the AGN Unified Model

    NASA Astrophysics Data System (ADS)

    Oh, Kyuseok; Yi, Sukyoung K.; Schawinski, Kevin; Koss, Michael; Trakhtenbrot, Benny; Soto, Kurt

    2015-07-01

    We have recently identified a substantial number of type 1 active galactic nuclei (AGNs) featuring weak broad-line regions (BLRs) at z\\lt 0.2 from detailed analysis of galaxy spectra in the Sloan Digital Sky Survey Data Release 7. These objects predominantly show a stellar continuum but also a broad Hα emission line, indicating the presence of a low-luminosity AGN oriented so that we are viewing the central engine directly without significant obscuration. These accreting black holes have previously eluded detection due to their weak nature. The newly discovered BLR AGNs have increased the number of known type 1 AGNs by 49%. Some of these new BLR AGNs were detected with the Chandra X-ray Observatory, and their X-ray properties confirm that they are indeed type 1 AGNs. Based on our new and more complete catalog of type 1 AGNs, we derived the type 1 fraction of AGNs as a function of [O iii] λ 5007 emission luminosity and explored the possible dilution effect on obscured AGNs due to star formation. The new type 1 AGN fraction shows much more complex behavior with respect to black hole mass and bolometric luminosity than has been suggested previously by the existing receding torus model. The type 1 AGN fraction is sensitive to both of these factors, and there seems to be a sweet spot (ridge) in the diagram of black hole mass and bolometric luminosity. Furthermore, we present the possibility that the Eddington ratio plays a role in determining opening angles.

  18. Obscured AGN Accretion Across Cosmic Time

    NASA Astrophysics Data System (ADS)

    Coil, Alison

    We propose to combine data from XMM-Newton, the Chandra X-ray Observatory, and the Spitzer Space Telescope with ground-based optical spectroscopy from Keck and Magellan to measure the relationship between AGN obscuration and accretion activity over the bulk of cosmic history. This work will establish the prominence of both obscured and unobscured growth phases of black holes and shed light on the processes that trigger and fuel AGN as a function of time. We will complete three complementary projects that focus on a) understanding the completeness and biases of AGN selection at mid-IR versus X-ray wavelengths, b) tracing optical obscuration as a function of luminosity and redshift, and c) measuring the distribution and evolution of X-ray absorption of AGN. We will undertake a study of AGN demographics comparing selection techniques at three different wavelengths: mid-IR selection using data from the Spitzer Space Telescope, X- ray selection using data from the XMM-Newton and Chandra satellites, and broad-line optical selection using PRIMUS spectroscopy. We will determine the overlap and uniqueness of samples created using each method, to quantify the completeness and biases inherent in AGN selection at each wavelength. This will lead to a constraint on the fraction of heavily obscured, Compton-thick AGN to z~1. To study the optical obscuration of AGN, we will use three recently-completed spectroscopic surveys -- PRIMUS, DEEP2, and our own Keck program -- to robustly determine the ratio of unobscured (broad-line) to obscured (non--broad-line) X-ray selected AGN as a function of luminosity from z~0.2 to z~3. We will utilize the well- understood selection functions and characterize the AGN completeness of each survey as a function of redshift, magnitude, and obscuration properties. This will allow us to correct for a variety of observational effects to measure the underlying joint redshift- and luminosity-dependence of optical obscuration, which has direct implications

  19. A method for determining AGN accretion phase in field galaxies

    NASA Astrophysics Data System (ADS)

    Micic, Miroslav; Martinović, Nemanja; Sinha, Manodeep

    2016-09-01

    Recent observations of active galactic nucleus (AGN) activity in massive galaxies (log M*/ M⊙ > 10.4) show the following: (1) at z < 1, AGN-hosting galaxies do not show enhanced merger signatures compared with normal galaxies, (2) also at z < 1, most AGNs are hosted by quiescent galaxies and (3) at z > 1, the percentage of AGNs in star-forming galaxies increases and becomes comparable to the AGN percentage in quiescent galaxies at z ˜ 2. How can major mergers explain AGN activity in massive quiescent galaxies that have no merger features and no star formation to indicate a recent galaxy merger? By matching merger events in a cosmological N-body simulation to the observed AGN incidence probability in the COSMOS survey, we show that major merger-triggered AGN activity is consistent with the observations. By distinguishing between `peak' AGNs (recently merger-triggered and hosted by star-forming galaxies) and `faded' AGNs (merger-triggered a long time ago and now residing in quiescent galaxies), we show that the AGN occupation fraction in star-forming and quiescent galaxies simply follows the evolution of the galaxy merger rate. Since the galaxy merger rate drops dramatically at z < 1, the only AGNs left to be observed are the ones triggered by old mergers that are now in the declining phase of their nuclear activity, hosted by quiescent galaxies. As we go towards higher redshifts, the galaxy merger rate increases and the percentages of `peak' AGNs and `faded' AGNs become comparable.

  20. Membranous glomerulonephritis in rheumatoid arthritis unrelated to gold, D-penicillamine or other connective tissue disease.

    PubMed

    Zarza, L P; Sanchez, E N; Acin, P A; Ara, J M; Baños, J G

    1996-07-01

    We report a 58-year-old woman with classical rheumatoid arthritis (RA) who developed a membranous glomerulonephritis (MGN). She had never been treated with gold or D-penicillamine; other connective tissue diseases as well as hepatitis B were excluded. We suggest that the responsible cause of MGN is RA. PMID:8853174

  1. Immunopathology of glomerulonephritis associated with chronic woodchuck hepatitis virus infection in woodchucks (Marmota monax).

    PubMed Central

    Peters, D. N.; Steinberg, H.; Anderson, W. I.; Hornbuckle, W. E.; Cote, P. J.; Gerin, J. L.; Lewis, R. M.; Tennant, B. C.

    1992-01-01

    Retrospective analysis of necropsy findings of 705 woodchucks was performed to determine the prevalence and morphology of immune-mediated glomerulonephritis, its relationship to woodchuck hepatitis virus (WHV) infection, and the presence of major WHV antigens. Twenty-six woodchucks had glomerular lesions. Renal tissue of the 26 animals was evaluated histologically and immunohistochemically for immune-mediated glomerulonephritis. Of these 26 animals, immune-mediated glomerulonephritis was diagnosed in six, all of which were chronic WHV carriers. Membranous glomerulonephritis was identified in three animals, two of which also had mesangial proliferation. Host immunoglobulin was present within the mesangium and along capillary loops in all three. Woodchuck hepatitis virus core antigen (WHcAg) was present along capillary loops of two of these animals, one membranous and one mixed, and in the mesangium of all three. Woodchuck hepatitis virus surface antigen (WHsAg) deposition was similar to WHcAg deposition but was only present along capillaries in those animals with mixed nephritis. The remaining three animals had mesangial proliferation. WHsAg and host immunoglobulin deposition were predominately mesangial; WHcAg was not detected. Transmission electron microscopy showed thickening of the capillary loop basement membranes and subepithelial electron-dense deposits in animal one, and deposits in the mesangium in animal six. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:1632459

  2. They Call Me Agnes: A Crow Narrative Based on the Life of Agnes Yellowtail Deernose.

    ERIC Educational Resources Information Center

    Voget, Fred W.; Mee, Mary K.

    This book is about life on the Crow Indian Reservation from around 1910 to the present and is based on the personal experiences of Donnie and Agnes Deernose. Following Donnie's death, Agnes became the principal narrator of the book. The Crow Indian Reservation is situated between Billings, Montana, and Sheridan, Wyoming. More so than any other…

  3. The Occurrence or Fibrillary Glomerulonephritis in Patients with Diabetes Mellitus May Not Be Coincidental: A Report of Four Cases

    PubMed Central

    González-Cabrera, Fayna; Henríquez-Palop, Fernando; Ramírez-Puga, Ana; Santana-Estupiñán, Raquel; Plaza-Toledano, Celia; Antón-Pérez, Gloria; Marrero-Robayna, Silvia; Ramírez-Medina, Davinia; Gallego-Samper, Roberto; Vega-Díaz, Nicanor; Camacho-Galan, Rafael; Rodríguez-Pérez, José C.

    2013-01-01

    Although clinical presentation of fibrillary glomerulonephritis is similar to most forms of glomerulonephritis, it is usually difficult to make the diagnosis. Clinical manifestations include proteinuria, microscopic haematuria, nephrotic syndrome, and impairment of renal function. A diagnosis of fibrillary glomerulonephritis is only confirmed by renal biopsy and it must comprise electronmicroscopy-verified ultrastructural findings. We report four cases between 45–50 years old with documented type 2 diabetes mellitus (T2DM) and arterial hypertension. All patients were found to have fibrils on kidney biopsy. The differential diagnosis of fibrils in the setting of diabetes mellitus is also discussed. PMID:23762079

  4. Calibrating AGN Feedback in Clusters

    NASA Astrophysics Data System (ADS)

    Wise, M. W.

    2009-12-01

    Whether caused by AGN jets, shocks, or mergers, the most definitive evidence for heating in cluster cores comes from X-ray spectroscopy. Unfortunately such spectra are essentially limited to studying the emission spectrum from the cluster as a whole. However since the same underlying emission measure distribution produces both the observed CCD and RGS spectra, X-ray imaging can still provide spatial information on the heating process. Using Chandra archival data for a sample of 9 clusters, we demonstrate how imaging data can be used to constrain departures from a canonical, isobaric cooling flow model as a function of position in a given cluster. The results of this analysis are also shown for the deep archival exposure of the Perseus cluster. Such ``heating maps'' can provide constraints on both the location and magnitude of the heating in the cores of clusters. When combined with detections and spectral index maps from low-frequency radio observations, these maps can be used to distinguish between different models for heating in these objects.

  5. The Angular Clustering of WISE-Selected AGN: Different Haloes for Obscured and Unobscured AGN

    NASA Astrophysics Data System (ADS)

    Yan, Lin

    2015-08-01

    We calculate the angular correlation function for a sample of 170,000 AGN extracted from the Wide-field Infrared Survey Explorer (WISE) catalog, selected to have red mid-IR colors (W1 - W2 > 0.8) and 4.6 micron flux densities brighter than 0.14 mJy). The sample is expected to be >90% reliable at identifying AGN, and to have a mean redshift of z=1.1. In total, the angular clustering of WISE-AGN is roughly similar to that of optical AGN. We cross-match these objects with the photometric SDSS catalog and distinguish obscured sources with (r - W2) > 6 from bluer, unobscured AGN. Obscured sources present a higher clustering signal than unobscured sources. Since the host galaxy morphologies of obscured AGN are not typical red sequence elliptical galaxies and show disks in many cases, it is unlikely that the increased clustering strength of the obscured population is driven by a host galaxy segregation bias. By using relatively complete redshift distributions from the COSMOS survey, we find obscured sources at mean redshift z=0.9 have a bias of b = 2.9 \\pm 0.6 and are hosted in dark matter halos with a typical mass of log(M/M_odot)~13.5. In contrast, unobscured AGN at z~1.1 have a bias of b = 1.6 \\pm 0.6 and inhabit halos of log(M/M_odot)~12.4. These findings suggest that obscured AGN inhabit denser environments than unobscured AGN, and are difficult to reconcile with the simplest AGN unification models, where obscuration is driven solely by orientation.

  6. Long Timescale Variability of AGN with RXTE

    NASA Astrophysics Data System (ADS)

    McHardy, I. M.; Uttley, P.; Taylor, R. D.; Seymour, N.

    2004-07-01

    In this paper we review the very large contribution made by RXTE to our understanding of Active Galaxies (AGN). We discuss the relationship between AGN and Galactic Black Hole X-ray binary systems (GBHs) and show, by comparison of their powerspectral densities (PSDs) that some AGN are the equivalent of GBHs in their `high' state, rather than in their `low' state as has previously been assumed. We plot the timescale at which the PSD slope steepens from -1 to -2 against the black hole mass for a sample of AGN, and for Cyg X-1 in its high and low states. We find it is not possible to fit all AGN to the same linear scaling of break timescale with black hole mass. However broad line AGN are consistent with a linear scaling of break timescale with mass from Cyg X-1 in its low state and NLS1 galaxies scale better with Cyg X-1 in its high state, although there is an exception, NGC3227. We suggest that the relationship between black hole mass and break timescale is a function of another underlying parameter which may be accretion rate or black hole spin or, probably, both. We examine X-ray spectral variability and show how simple `flux-flux' plots can distinguish between `two-component' and `spectral pivoting' models. We also examine the relationship between the X-ray emission and that in other wavebands. In the case of X-ray/optical variability we show how cooler discs in AGN with larger mass black holes lead to greater proximity of the X-ray and optical emission regions and hence to more highly correlated variability. The very large amplitude of optical variability then rules out reprocessing as the origin of the optical emission. We show how the radio emission in NGC 4051 is strongly correlated with the X-ray emission, implying some contribution to the X-ray emission from a jet for which there is some evidence in radio images. We point out, however, that we have only studied in detail the X-ray variability of a handful of AGN. There is a strong requirement to extend such

  7. Steps Toward Unveiling the True Population of AGN: Photometric Selection of Broad-Line AGN

    NASA Astrophysics Data System (ADS)

    Schneider, Evan; Impey, C.

    2012-01-01

    We present an AGN selection technique that enables identification of broad-line AGN using only photometric data. An extension of infrared selection techniques, our method involves fitting a given spectral energy distribution with a model consisting of three physically motivated components: infrared power law emission, optical accretion disk emission, and host galaxy emission. Each component can be varied in intensity, and a reduced chi-square minimization routine is used to determine the optimum parameters for each object. Using this model, both broad- and narrow-line AGN are seen to fall within discrete ranges of parameter space that have plausible bounds, allowing physical trends with luminosity and redshift to be determined. Based on a fiducial sample of AGN from the catalog of Trump et al. (2009), we find the region occupied by broad-line AGN to be distinct from that of quiescent or star-bursting galaxies. Because this technique relies only on photometry, it will allow us to find AGN at fainter magnitudes than are accessible in spectroscopic surveys, and thus probe a population of less luminous and/or higher redshift objects. With the vast availability of photometric data in large surveys, this technique should have broad applicability and result in large samples that will complement X-ray AGN catalogs.

  8. Satellites of radio AGN in SDSS: Insights into agn triggering and feedback

    SciTech Connect

    Pace, Cameron; Salim, Samir E-mail: salims@indiana.edu

    2014-04-10

    We study the effects of radio jets on galaxies in their vicinity (satellites) and the role of satellites in triggering radio-loud active galactic nuclei (AGNs). The study compares the aggregate properties of satellites of a sample of 7220 radio AGNs at z < 0.3 (identified by Best and Heckman from the SDSS and NVSS+FIRST surveys) to the satellites of a control sample of radio-quiet galaxies, which are matched in redshift, color, luminosity, and axis ratio, as well as by environment type: field galaxies, cluster members, and brightest cluster galaxies (BCGs). Remarkably, we find that radio AGNs exhibit on average a 50% excess (17σ significance) in the number of satellites within 100 kpc even though the cluster membership was controlled (e.g., radio BCGs have more satellites than radio-quiet BCGs, etc.). Satellite excess is not confirmed for high-excitation sources, which are only 2% of radio AGN. Extra satellites may be responsible for raising the probability for hot gas AGN accretion via tidal effects or may otherwise enhance the intensity or duration of the radio-emitting phase. Furthermore, we find that the incidence of radio AGNs among potential hosts (massive ellipticals) is similar for field galaxies and for non-BCG cluster members, suggesting that AGN fueling depends primarily on conditions in the host halo rather than the parent, cluster halo. Regarding feedback, we find that radio AGNs, either high or low excitation, have no detectable effect on star formation in their satellites, as neither induced star formation nor star formation quenching is present in more than ∼1% of radio AGN.

  9. Observational evidence for thin AGN disks

    NASA Technical Reports Server (NTRS)

    Netzer, Hagai

    1992-01-01

    AGN spectrum and spectral features, polarization, inclination, and X-ray line and continuum reflection features are discussed in a critical way in order to determine the ones that are the least model-dependent. The sign and strength of absorption and emission edges are found to be model-dependent, and relativistic broadening and shifting makes them hard to detect. The presence or absence of the predicted Lyman edge polarization feature may be used as a decisive test for thin, bare AGN disks. Other good model-independent tests are several inclination-related line and continuum correlations in big AGN samples. It is shown that electron temperature near the surface of the disk can greatly exceed the disk equilibrium temperature, which causes deviations from LTE. This effect must be incorporated into realistic disk models.

  10. A multi-wavelength survey of AGN in massive clusters: AGN distribution and host galaxy properties

    NASA Astrophysics Data System (ADS)

    Klesman, Alison J.; Sarajedini, Vicki L.

    2014-07-01

    We investigate the effect of environment on the presence and fuelling of active galactic nuclei (AGN) by identifying galaxies hosting AGN in massive galaxy clusters and the fields around them. We have identified AGN candidates via optical variability (178), X-ray emission (74), and mid-IR SEDs (64) in multi-wavelength surveys covering regions centred on 12 galaxy clusters at redshifts 0.5 < z < 0.9. In this paper, we present the radial distribution of AGN in clusters to examine how local environment affects the presence of an AGN and its host galaxy. While distributions vary from cluster to cluster, we find that the radial distribution of AGN generally differs from that of normal galaxies. X-ray-selected AGN candidates appear to be more centrally concentrated than normal galaxies in the inner 20 per cent of the virial radius, while becoming less centrally concentrated in the outer regions. Mid-IR-selected AGN are less centrally concentrated overall. Optical variables have a similar distribution to normal galaxies in the inner regions, then become somewhat less centrally concentrated farther from the cluster centre. The host galaxies of AGN reveal a different colour distribution than normal galaxies, with many AGN hosts displaying galaxy colours in the `green valley' between the red sequence and blue star-forming normal galaxies. This result is similar to those found in field galaxy studies. The colour distribution of AGN hosts is more pronounced in disturbed clusters where minor mergers, galaxy harassment, and interactions with cluster substructure may continue to prompt star formation in the hosts. Among normal galaxies, we find that galaxy colours become generally bluer with increasing cluster radius, as is expected. However, we find no relationship between host galaxy colour and cluster radius among AGN hosts, which may indicate that processes related to the accreting supermassive black hole have a greater impact on the star-forming properties of the host galaxy

  11. γ-Ray Generation in Microquasars: the link with AGN

    NASA Astrophysics Data System (ADS)

    Latham, I. J.; Aye, K.-M.; Brown, A. M.; Chadwick, P. M.; Hadjichristidis, C. N.; Le Gallou, R.; McComb, T. J. L.; Nolan, S. J.; Orford, K. J.; Osborne, J. L.; Noutsos, A.; Rayner, S. M.

    2005-02-01

    The link between the physical processes responsible for high energy emission from relativistic jets in AGN and microquasars is investigated. A Fortran code based on an existing inhomogeneous, synchrotron self-Compton (SSC) model, for AGN is presented. The code is then applied to the AGN 3C 279 and the microquasar LS5039. Spectral energy distributions (SED's) are presented.

  12. FE Features in Highly Obscured AGN

    NASA Technical Reports Server (NTRS)

    Schachter, Jonathan F.

    1999-01-01

    This final report is a summary of the combined study of ASCA (Advanced Satellite for Cosmology and Astrophysics) observations of NGC 7582 with archival ROSAT HRI (High Resolution Imager) and PSPC (Position Sensitive Proportional Counter) data. These observations were important in that they established that X-ray emission in NGC 7582, the most narrow-line of NLXGs (narrow-line X-ray galaxies), is associated with an AGN (Active Galactic Nuclei). Thus implying that all NLXGs are obscured AGN, as has been hypothesized to explain the X-ray spectral background paradox.

  13. Nephrotic range proteinuria in c-ANCA-positive crescentic glomerulonephritis with linear immune deposits

    PubMed Central

    Singh, N. P.; Gulati, S.; Garg, V.; Beniwal, P.; Garg, S.

    2008-01-01

    The three broad groups of rapidly progressing glomerulonephritis are anti glomerular basement membrane (anti-GBM) disease, renal vasculitis characterized by antineutrophil cytoplasmic antibody positivity, and a heterogeneous group with granular immune deposits. Anti-GBM disease with cytoplasmic antineutrophilic antibodies (c-ANCA) positivity (type III disease) is not known to present with nephrotic syndrome. We report here a rare presentation of nephrotic syndrome in Type III disease. Larger studies are warranted to determine whether the amount and/or type of immune deposits decide the range of proteinuria. These studies are also required to elucidate the impact of immune complex deposition on renal disease in c-ANCA-positive glomerulonephritis and to outline its pathogenetic mechanism. PMID:20142931

  14. Heartworm (Dirofilaria immitis) disease and glomerulonephritis in a black-footed cat (Felis nigripes).

    PubMed

    Deem, S L; Heard, D J; LaRock, R

    1998-06-01

    A 6-yr-old, 1.36-kg, intact female black-footed cat (Felis nigripes) was presented to the Veterinary Medical Teaching Hospital, University of Florida, with a history of depression, lethargy, and anorexia. Cardiac dysfunction and renal failure were diagnosed on the basis of antemortem and postmortem findings. At necropsy, heartworms (Dirofilaria immitis), glomerulonephritis, and endometritis were present. The glomerulonephritis could have been immune mediated and may have been associated with the heartworm infection or the chronic endometritis or both. Heartworm disease should be included in the list of differential diagnoses for any exotic cat housed outdoors in an endemic heartworm region that dies peracutely or has suggestive gastrointestinal or respiratory signs. Heartworm prophylaxis and annual serologic testing in exotic cats housed outdoors in heartworm endemic regions are recommended. PMID:9732037

  15. Familial C3 glomerulonephritis associated with mutations in the gene for complement factor B.

    PubMed

    Imamura, Hideaki; Konomoto, Takao; Tanaka, Etsuko; Hisano, Satoshi; Yoshida, Yoko; Fujimura, Yoshihiro; Miyata, Toshiyuki; Nunoi, Hiroyuki

    2015-05-01

    We report the first case of familial C3 glomerulonephritis (C3GN) associated with mutations in the gene for complement factor B (CFB). A 12-year-old girl was diagnosed with biopsy-proven C3GN. Her mother had a history of treatment for membranoproliferative glomerulonephritis, and her brother had hypocomplementemia without urinary abnormalities. DNA analysis revealed heterozygosity for CFB p.S367R in the patient, mother and brother. Evaluation of the structure-function relationship supports that this mutation has gain-of-function effects in CFB. The present case suggests that CFB has an important role in the etiology of C3GN and provides a new insight into anticomplement therapy approaches. PMID:25758434

  16. Hepatitis E Virus-Induced Cryoglobulinemic Glomerulonephritis in a Nonimmunocompromised Person.

    PubMed

    Guinault, Damien; Ribes, David; Delas, Audrey; Milongo, David; Abravanel, Florence; Puissant-Lubrano, Bénédicte; Izopet, Jacques; Kamar, Nassim

    2016-04-01

    Hepatitis E virus (HEV)-related kidney disease and symptomatic cryoglobulinemia have been observed in solid-organ transplant recipients. However, HEV RNA in the cryoprecipitate has not yet been assessed. We report what to our knowledge is the first documented case of autochthonous HEV-induced cryoglobulinemic crescentic and membranoproliferative glomerulonephritis in an immunocompetent man with no notable medical history. He presented with edema, hypertension, increased serum creatinine level, and nephrotic syndrome. Type II cryoglobulinemia with monoclonal immunoglobulin G (IgG) κ light chain was detected. Anti-HEV IgG and IgM, as well as HEV RNA, were detected in serum and cryoprecipitate. Histologic analysis of a kidney biopsy specimen revealed features of crescentic and membranoproliferative glomerulonephritis. After HEV clearance, kidney and liver parameters improved and HEV RNA and cryoglobulinemia were undetectable. Hence, we conclude that HEV can cause severe kidney disease and should be considered in cases of unexplained glomerular disease. PMID:26682764

  17. Ameliorative effects of arctiin from Arctium lappa on experimental glomerulonephritis in rats.

    PubMed

    Wu, Jian-Guo; Wu, Jin-Zhong; Sun, Lian-Na; Han, Ting; Du, Jian; Ye, Qi; Zhang, Hong; Zhang, Yu-Guang

    2009-11-01

    Membranous glomerulonephritis (MGN) remains the most common cause of adult-onset nephrotic syndrome in the world and up to 40% of untreated patients will progress to end-stage renal disease. Although the treatment of MGN with immunosuppressants or steroid hormones can attenuate the deterioration of renal function, numerous treatment-related complications have also been established. In this study, the ameliorative effects of arctiin, a natural compound isolated from the fruits of Arctium lappa, on rat glomerulonephritis induced by cationic bovine serum albumin (cBSA) were determined. After oral administration of arctiin (30, 60, 120 mg/kgd) for three weeks, the levels of serum creatinine (Scr) and blood urea nitrogen (BUN) and 24-h urine protein content markedly decreased, while endogenous creatinine clearance rate (ECcr) significantly increased. The parameters of renal lesion, hypercellularity, infiltration of polymorphonuclear leukocyte (PMN), fibrinoid necrosis, focal and segmental proliferation and interstitial infiltration, were reversed. In addition, we observed that arctiin evidently reduced the levels of malondialdehyde (MDA) and pro-inflammatory cytokines including interleukin-6 (IL-6) and tumor necrosis factor (TNF-alpha), suppressed nuclear factor-kappaB p65 (NF-kappaB) DNA binding activity, and enhanced superoxide dismutase (SOD) activity. These findings suggest that the ameliorative effects of arctiin on glomerulonephritis is carried out mainly by suppression of NF-kappaB activation and nuclear translocation and the decreases in the levels of these pro-inflammatory cytokines, while SOD is involved in the inhibitory pathway of NF-kappaB activation. Arctiin has favorable potency for the development of an inhibitory agent of NF-kappaB and further application to clinical treatment of glomerulonephritis, though clinical studies are required. PMID:19524415

  18. A Global Picture of AGN Winds

    NASA Technical Reports Server (NTRS)

    Kazanas, D.; Fukumura, K.

    2011-01-01

    We present a unified structure for accretion powered sources across their entire luminosity range from accreting galactic black holes to the most luminous quasars, with emphasis on AGN and their phenomenology. Central to this end is the notion of MHD winds launched from the accretion disks that power these objects. This work similar in spirit to that of Elvis of more that a decade ago, provides, on one hand, only the broadest characteristics of these objects, but on the other, also scaling laws that allow one to make contact with objects of different luminosity. The conclusion of this work is that AGN phenomenology can be accounted for in terms of dot(m), the wind mass flux in units of the Eddington value, the observer's inclination angle theta and alpha_OX the logarithmic slope between UV and X-ray flares. However given the well known correlation between alpha(sub ox) and UV Luminosity, we conclude that the AGN structure depends on only two parameters. The small number of model parameters hence suggests that an understanding of the global AGN properties maybe within reach.

  19. Mid-IR Observations of AGN

    NASA Astrophysics Data System (ADS)

    Packham, Christopher C.; Alonso Herrero, Almudena; Levenson, Nancy A.; Piratas AGN Group

    2016-01-01

    We present new observations of AGN, predominantly from the 10.4m GranTeCan. These observations are modeled and interpreted within the context of the clumpy torus models. In this poster we present our recent results and interpretation of the model outputs.

  20. Mabel Agnes Elliott, We Hardly Knew You

    ERIC Educational Resources Information Center

    McGonigal, Kathryn; Galliher, John F.

    2008-01-01

    Sociologist Mabel Agnes Elliott was elected the fourth president of the Society for the Study of Social Problems in 1956-1957 and was the first woman to hold this position. She was an anti-war activist, a feminist and a creative and diligent writer. Yet she experienced many challenges. The Federal Bureau of Investigation kept an active file on…

  1. The Horizon-AGN Simulation: Morphological Diversity of Galaxies ,Promoted by AGN Feedback

    NASA Astrophysics Data System (ADS)

    Dubois, Yohan; Peirani, Sébastien; Pichon, Christophe; Devriendt, Julien; Gavazzi, Raphaël; Welker, Charlotte; Volonteri, Marta

    2016-09-01

    The interplay between cosmic gas accretion onto galaxies and galaxy mergers drives the observed morphological diversity of galaxies. By comparing the state-of-the-art hydrodynamical cosmological simulations HORIZON-AGN and HORIZON-NOAGN, we unambiguously identify the critical role of Active Galactic Nuclei (AGN) in setting up the correct galaxy morphology for the massive end of the population. With AGN feedback, typical kinematic and morpho-metric properties of galaxy populations as well as the galaxy-halo mass relation are in much better agreement with observations. Only AGN feedback allows massive galaxies at the center of groups and clusters to become ellipticals, while without AGN feedback those galaxies reform discs. It is the merger-enhanced AGN activity that is able to freeze the morphological type of the post-merger remnant by durably quenching its quiescent star formation. Hence morphology is shown not to be purely driven by mass but also by the nature of cosmic accretion: at constant galaxy mass, ellipticals are galaxies that are mainly assembled through mergers, while discs are preferentially built from the in situ star formation fed by smooth cosmic gas infall.

  2. CCR6 Recruits Regulatory T Cells and Th17 Cells to the Kidney in Glomerulonephritis

    PubMed Central

    Turner, Jan-Eric; Paust, Hans-Joachim; Steinmetz, Oliver M.; Peters, Anett; Riedel, Jan-Hendrik; Erhardt, Annette; Wegscheid, Claudia; Velden, Joachim; Fehr, Susanne; Mittrücker, Hans-Willi; Tiegs, Gisa; Stahl, Rolf A.K.

    2010-01-01

    T cells recruited to the kidney contribute to tissue damage in crescentic and proliferative glomerulonephritides. Chemokines and their receptors regulate T cell trafficking, but the expression profile and functional importance of chemokine receptors for renal CD4+ T cell subsets are incompletely understood. In this study, we observed that renal FoxP3+CD4+ regulatory T cells (Tregs) and IL-17–producing CD4+ T (Th17) cells express the chemokine receptor CCR6, whereas IFNγ-producing Th1 cells are CCR6−. Induction of experimental glomerulonephritis (nephrotoxic nephritis) in mice resulted in upregulation of the only CCR6 ligand, CCL20, followed by T cell recruitment, renal tissue injury, albuminuria, and loss of renal function. CCR6 deficiency aggravated renal injury and increased mortality (from uremia) among nephritic mice. Compared with wild-type (WT) mice, CCR6 deficiency reduced infiltration of Tregs and Th17 cells but did not affect recruitment of Th1 cells in the setting of glomerulonephritis. Adoptive transfer of WT but not CCR6-deficient Tregs attenuated morphologic and functional renal injury in nephritic mice. Furthermore, reconstitution with WT Tregs protected CCR6−/− mice from aggravated nephritis. Taken together, these data suggest that CCR6 mediates renal recruitment of both Tregs and Th17 cells and that the reduction of anti-inflammatory Tregs in the presence of a fully functional Th1 response aggravates experimental glomerulonephritis. PMID:20299360

  3. P2X7 Deficiency Attenuates Renal Injury in Experimental Glomerulonephritis

    PubMed Central

    Taylor, Simon R.J.; Turner, Clare M.; Elliott, James I.; McDaid, John; Hewitt, Reiko; Smith, Jennifer; Pickering, Matthew C.; Whitehouse, Darren L.; Cook, H. Terence; Burnstock, Geoffrey; Pusey, Charles D.; Unwin, Robert J.; Tam, Frederick W.K.

    2009-01-01

    The P2X7 receptor is a ligand-gated cation channel that is normally expressed by a variety of immune cells, including macrophages and lymphocytes. Because it leads to membrane blebbing, release of IL-1β, and cell death by apoptosis or necrosis, it is a potential therapeutic target for a variety of inflammatory diseases. Although the P2X7 receptor is usually not detectable in normal renal tissue, we previously reported increased expression of both mRNA and protein in mesangial cells and macrophages infiltrating the glomeruli in animal models of antibody-mediated glomerulonephritis. In this study, we used P2X7-knockout mice in the same experimental model of glomerulonephritis and found that P2X7 deficiency was significantly renoprotective compared with wild-type controls, evidenced by better renal function, a striking reduction in proteinuria, and decreased histologic glomerular injury. In addition, the selective P2X7 antagonist A-438079 prevented the development of antibody-mediated glomerulonephritis in rats. These results support a proinflammatory role for P2X7 in immune-mediated renal injury and suggest that the P2X7 receptor is a potential therapeutic target. PMID:19389853

  4. X-ray selected AGN in a Merging Cluster Environment

    NASA Astrophysics Data System (ADS)

    Norman, Dara; Coldwell, Georgina; Soechting, Ilona

    2010-08-01

    Although a general understanding of the overall AGN population is being addressed by optical large area surveys, a complete picture of cluster AGN is hampered by survey biases and a lack of information about AGN environments where we can trace cluster interactions. Optically selected AGN are under-represented in cluster environments due to color selection criteria insensitive to red and dusty sources. X-ray selection of AGN can overcome this bias. Hierarchical simulations suggest the gravitational processes which govern the evolution of clusters also have a role in AGN triggering, and AGN feedback is critically important to galaxy evolution. Confirmation of models requires comparisons not just of the cluster galaxy population, but also of the distributions of AGN in clusters especially forming clusters, which are not fully identified in surveys. Weak lensing cluster selection can overcome this bias. We propose to obtain GMOS-S spectra for a sample of 23 X-ray selected , optically faint (20 with R>20.3) AGN cluster candidates in an X-ray cluster discovered by its weak lensing shear signal. This cluster is unique in the large number of 1) X-ray AGN candidates identified in its environment and 2) X-ray sub-clusters identified. We require redshift data to identify AGN cluster members.

  5. AGN identification and host galaxies properties in the MOSDEF survey

    NASA Astrophysics Data System (ADS)

    Azadi, Mojegan; Coil, Alison L.; MOSDEF team

    2016-06-01

    We present new results on the identification and host galaxy properties of X-ray, IR and optically-selected AGN at 1.4 < z < 3.8, using spectroscopic data from the on-going MOSDEF survey, which is obtaining rest-frame optical spectra of ~1,500 galaxies and AGN using the new Keck/MOSFIRE instrument. We find clear selection effects when identifying AGN at different wavelengths, in that optically-selected AGN are more likely to be found in galaxies with low SFR, while IR AGN are typically found in galaxies with higher SFR. There is also a bias against finding AGN at any wavelength in low mass galaxies. We find that optical AGN selection identifies less powerful AGN that may be obscured at other wavelengths. Combining the AGN we identify at different wavelengths, we find that AGN host galaxies have similar stellar age and dust content as inactive galaxies of the same stellar mass. Finally, we do not find a significant correlation between either SFR or stellar mass and L[OIII], which argues against the presence of strong AGN feedback.

  6. A POWERFUL AGN OUTBURST IN RBS 797

    SciTech Connect

    Cavagnolo, K. W.; McNamara, B. R.; Wise, M. W.; Nulsen, P. E. J.; Gitti, M.; Brueggen, M.; Rafferty, D. A.

    2011-05-10

    Utilizing {approx}50 ks of Chandra X-Ray Observatory imaging, we present an analysis of the intracluster medium (ICM) and cavity system in the galaxy cluster RBS 797. In addition to the two previously known cavities in the cluster core, the new and deeper X-ray image has revealed additional structure associated with the active galactic nucleus (AGN). The surface brightness decrements of the two cavities are unusually large and are consistent with elongated cavities lying close to our line of sight. We estimate a total AGN outburst energy and mean jet power of {approx}(3-6) x 10{sup 60} erg and {approx}(3-6) x 10{sup 45} erg s{sup -1}, respectively, depending on the assumed geometrical configuration of the cavities. Thus, RBS 797 is apparently among the most powerful AGN outbursts known in a cluster. The average mass accretion rate needed to power the AGN by accretion alone is {approx}1 M{sub sun} yr{sup -1}. We show that accretion of cold gas onto the AGN at this level is plausible, but that Bondi accretion of the hot atmosphere is probably not. The brightest cluster galaxy (BCG) harbors an unresolved, non-thermal nuclear X-ray source with a bolometric luminosity of {approx}2 x 10{sup 44} erg s{sup -1}. The nuclear emission is probably associated with a rapidly accreting, radiatively inefficient accretion flow. We present tentative evidence that star formation in the BCG is being triggered by the radio jets and suggest that the cavities may be driving weak shocks (M {approx} 1.5) into the ICM, similar to the process in the galaxy cluster MS 0735.6+7421.

  7. Decreased specific star formation rates in AGN host galaxies

    NASA Astrophysics Data System (ADS)

    Shimizu, T. Taro; Mushotzky, Richard F.; Meléndez, Marcio; Koss, Michael; Rosario, David J.

    2015-09-01

    We investigate the location of an ultra-hard X-ray selected sample of active galactic nuclei (AGN) from the Swift Burst Alert Telescope (BAT) catalogue with respect to the main sequence (MS) of star-forming galaxies using Herschel-based measurements of the star formation rate (SFR) and M*'s from Sloan Digital Sky Survey photometry where the AGN contribution has been carefully removed. We construct the MS with galaxies from the Herschel Reference Survey and Herschel Stripe 82 Survey using the exact same methods to measure the SFR and M* as the Swift/BAT AGN. We find that a large fraction of the Swift/BAT AGN lie below the MS indicating decreased specific SFR (sSFR) compared to non-AGN galaxies. The Swift/BAT AGN are then compared to a high-mass galaxy sample (CO Legacy Database for GALEX Arecibo SDSS Survey, COLD GASS), where we find a similarity between the AGN in COLD GASS and the Swift/BAT AGN. Both samples of AGN lie firmly between star-forming galaxies on the MS and quiescent galaxies far below the MS. However, we find no relationship between the X-ray luminosity and distance from the MS. While the morphological distribution of the BAT AGN is more similar to star-forming galaxies, the sSFR of each morphology is more similar to the COLD GASS AGN. The merger fraction in the BAT AGN is much higher than the COLD GASS AGN and star-forming galaxies and is related to distance from the MS. These results support a model in which bright AGN tend to be in high-mass star-forming galaxies in the process of quenching which eventually starves the supermassive black hole itself.

  8. Mast Cell Stabilization Ameliorates Autoimmune Anti-Myeloperoxidase Glomerulonephritis.

    PubMed

    Gan, Poh-Yi; O'Sullivan, Kim M; Ooi, Joshua D; Alikhan, Maliha A; Odobasic, Dragana; Summers, Shaun A; Kitching, A Richard; Holdsworth, Stephen R

    2016-05-01

    Observations in experimental murine myeloperoxidase (MPO)-ANCA-associated vasculitis (AAV) show mast cells degranulate, thus enhancing injury as well as producing immunomodulatory IL-10. Here we report that, compared with biopsy specimens from control patients, renal biopsy specimens from 44 patients with acute AAV had more mast cells in the interstitium, which correlated with the severity of tubulointerstitial injury. Furthermore, most of the mast cells were degranulated and spindle-shaped in patients with acute AAV, indicating an activated phenotype. We hypothesized that the mast cell stabilizer disodium cromoglycate would attenuate mast cell degranulation without affecting IL-10 production. We induced anti-MPO GN by immunizing mice with MPO and a low dose of anti-glomerular basement membrane antibody. When administered before or after induction of MPO autoimmunity in these mice, disodium cromoglycate attenuated mast cell degranulation, development of autoimmunity, and development of GN, without diminishing IL-10 production. In contrast, administration of disodium cromoglycate to mast cell-deficient mice had no effect on the development of MPO autoimmunity or GN. MPO-specific CD4(+) effector T cell proliferation was enhanced by co-culture with mast cells, but in the presence of disodium cromoglycate, proliferation was inhibited and IL-10 production was enhanced. These results indicate that disodium cromoglycate blocks injurious mast cell degranulation specifically without affecting the immunomodulatory role of these cells. Thus as a therapeutic, disodium cromoglycate may substantially enhance the regulatory role of mast cells in MPO-AAV. PMID:26374606

  9. Complication of Corticosteroid Treatment by Acute Plasmodium malariae Infection Confirmed by Small-Subunit rRNA Sequencing▿

    PubMed Central

    To, Kelvin K. W.; Teng, Jade L. L.; Wong, Samson S. Y.; Ngan, Antonio H. Y.; Yuen, Kwok-Yung; Woo, Patrick C. Y.

    2010-01-01

    We report a case of acute Plasmodium malariae infection complicating corticosteroid treatment for membranoproliferative glomerulonephritis in a patient from an area where P. malariae infection is not endemic. A peripheral blood smear showed typical band-form trophozoites compatible with P. malariae or Plasmodium knowlesi. SSU rRNA sequencing confirmed the identity to be P. malariae. PMID:20739487

  10. AGN feedback in the Perseus cluster

    NASA Astrophysics Data System (ADS)

    Gendron-Marsolais, Marie-Lou; Hlavacek-Larrondo, Julie; Clarke, Tracy E.; Intema, Huib; Fabian, Andrew C.; Taylor, Gregory B.; Blundell, Katherine

    2016-04-01

    Deep Chandra images of the Perseus cluster of galaxies have revealed a succession of cavities created by the jets of the central supermassive black hole, pushing away the X-ray emitting gas and leaving bubbles filled with radio emission. Perseus is one of the rare examples showing buoyantly rising lobes from past radio outbursts, characterized by a steep spectral index and known as ghost cavities. All of these structures trace the complete history of mechanical AGN feedback over the past 500 Myrs. I will present results on new, ultra deep 230-470 MHz JVLA data. This low-frequency view of the Perseus cluster will probe the old radio-emitting electron population and will allow us to build the most detailed map of AGN feedback in a cluster thus far.

  11. Discovering Rare AGN with Stripe 82X

    NASA Astrophysics Data System (ADS)

    LaMassa, S.; Urry, C.; Cappelluti, N.; Comastri, A.; Glikman, E.; Richards, G.; Boehringer, H.; Murray, S.; Civano, F.

    2014-07-01

    We have begun a wide-area survey overlapping the Sloan Digital Sky Survey (SDSS) region Stripe 82 which contains extensive multi-wavelength coverage from both ground- and space-based observatories. With the initial data release of Stripe 82X, covering 16.5 deg^{2} from XMM-Newton and Chandra, we identified ˜3300 X-ray sources, including the highest spectroscopically confirmed X-ray selected quasar to date (z = 5.86). I will review the science highlights of this survey so far, including the space density of high luminosity AGN and results from our ground-based campaign to target optically dull, infrared bright targets, which are prime candidates for obscured AGN at high redshift. I will conclude with a discussion of what we expect to learn with the additional 20 deg^{2} of coverage with XMM-Newton awarded to us in AO 13, which will more than double our current survey area.

  12. The universal spectrum of AGNs and QSOs

    NASA Technical Reports Server (NTRS)

    Kazanas, D.

    1985-01-01

    The effects of the feedback of e(+)-e(-) pair reinjection in a plasma due to photon photon absorption of its own radiation are examined. A mechanism is presented which can produce an electron distribution function that can account for the overall spectral distribution of radiation of AGNs and QSOs and the specific slopes observed in the IR to UV and 2-50 keV bands. It is interesting to note that the necessary condition for this mechanism to work (i.e., most of energy injected at e(M sub e)(C sup 2) is realized in the accretion shock model of Kazanas and Ellison. This mechanism involves only one free parameter the compactness of the sources, L/R, whose mean value can also account for the diffuse gamma ray background in terms of AGNs.

  13. AGN feedback in galaxy clusters and groups

    NASA Astrophysics Data System (ADS)

    Hardcastle, Martin

    2016-07-01

    Mechanical feedback via Active Galactic Nuclei (AGN) jets in the centres of galaxy groups and clusters is a crucial ingredient in current models of galaxy formation and cluster evolution. Jet feedback is believed to regulate gas cooling and thus star formation in the most massive galaxies, but a robust physical understanding of this feedback mode is currently lacking. Athena will provide (1) the first kinematic measurements on relevant spatial scales of the hot gas in galaxy, group and cluster haloes as it absorbs the impact of AGN jets, and (2) vastly improved ability to map thermodynamic conditions on scales well-matched to the jets, lobes and gas disturbances produced by them. I will present new predictions of Athena's ability to measure the energetic impact of powerful jets based on our most recent set of numerical models.

  14. Jets in AGN at extremely high redshifts

    NASA Astrophysics Data System (ADS)

    Gurvits, Leonid I.; Frey, Sándor; Paragi, Zsolt

    2015-03-01

    The jet phenomenon is a trademark of active galactic nuclei (AGN). In most general terms, the current understanding of this phenomenon explains the jet appearance by effects of relativistic plasma physics. The fundamental source of energy that feeds the plasma flow is believed to be the gravitational field of a central supermassive black hole. While the mechanism of energy transfer and a multitude of effects controlling the plasma flow are yet to be understood, major properties of jets are strikingly similar in a broad range of scales from stellar to galactic. They are supposed to be controlled by a limited number of physical parameters, such as the mass of a central black hole and its spin, magnetic field induction and accretion rate. In a very simplified sense, these parameters define the formation of a typical core-jet structure observed at radio wavelengths in the region of the innermost central tens of parsecs in AGN. These core-jet structures are studied in the radio domain by Very Long Baseline Interferometry (VLBI) with milli- and sub-milliarcsecond angular resolution. Such structures are detectable at a broad range of redshifts. If observed at a fixed wavelength, a typical core-jet AGN morphology would appear as having a steep-spectrum jet fading away with the increasing redshift while a flat-spectrum core becoming more dominant. If core-jet AGN constitute the same population of objects throughout the redshift space, the apparent ``prominence'' of jets at higher redshifts must decrease (Gurvits 1999): well pronounced jets at high z must appear less frequent than at low z.

  15. The softest Einstein AGN (active galactic nuclei)

    SciTech Connect

    Cordova, F.A.; Kartje, J.; Mason, K.O.; Mittaz, J.P.D.; Chicago Univ., IL; University Coll., London . Mullard Space Science Lab.)

    1989-01-01

    We have undertaken a coarse spectral study to find the softest sources detected with the Imaging Proportional Counter (IPC) on the Einstein Observatory. Of the nearly 7700 IPC sources, 226 have color ratios that make them candidate ultrasoft'' sources; of these, 83 have small enough errors that we can say with confidence that they have a spectral component similar to those of the white dwarfs Sirius and HZ 43, nearby stars such as {alpha} Cen and Procyon, and typical polar'' cataclysmic variables. By means of catalog searches and ground-based optical and radio observations we have thus far identified 96 of the 226 candidate soft sources; 37 of them are active galactic nuclei (AGN). In the more selective subset of 83 sources, 47 have been identified, 12 of them with AGN. The list of 47 identifications is given in Cordova et al. For one QSO in our sample, E0132.8--411, we are able to fit the pulse-height data to a power-law model and obtain a best fit for the energy spectral index of 2. 2{sub {minus}0.4}{sup +0.6}. For the remainder of the AGN in the higher confidence sample we are able to infer on the basis of their x-ray colors that they have a similar spectral component. Two-thirds of the AGN are detected below 0.5 keV only, while the remainder evidence a flatter spectral component in addition to the ultra-soft component. 14 refs., 5 figs.

  16. AGN Black Hole Masses from Reverberation Mapping

    NASA Technical Reports Server (NTRS)

    Peterson, B. M.

    2004-01-01

    Emission-line variability data on bright AGNs indicates that the central objects in these sources have masses in the million to few-hundred million solar mass range. The time-delayed response of the emission lines to continuum variations can be used to infer the size of the line-emitting region via light travel-time arguments. By combining these sizes with the Doppler widths of the variable part of the emission lines, a virial mass estimate can be obtained. For three especially well-studied sources, NGC 5548, NGC 7469, and 3C 390.3, data on multiple emission lines can be used to test the virial hypothesis. In each of these cases, the response time of the various emission lines is anticorrelated with the line width, with the dependence as expected for gravitationally bound motion of the line-emitting clouds, i.e., that the square of the Doppler line width is inversely proportional to the emission-line time delay. Virial masses based on the Balmer lines have now been measured for about three dozen AGNs. Systematic effects currently limit the accuracy of these masses to a factor of several, but characteristics of the radius-luminosity and mass-luminosity relationships for AGNs are beginning to emerge.

  17. Do stars contribute to AGN fuelling?

    NASA Astrophysics Data System (ADS)

    Davies, Richard

    2011-11-01

    While the existence of a starburst-AGN connection is undisputed, there is no consensus on whether AGN fuelling is synchronous with star formation or follows it during a post-starburst phase. I begin by presenting an overview of some of the observational evidence and theoretical models favouring each perspective. I then focus on recent high resolution observations that are able to probe the central tens of parsecs where star formation might influence AGN activity. I show that both the starburst phase and the physical state of the dense molecular gas imply that stellar feedback plays a critical role in first hindering and then helping accretion. I argue that it is only after the early turbulent phases of a starburst that gas from slow stellar winds can accrete efficiently to smaller scales. And I outline other contexts where similar processes appear to be at work. I finish by showing how the properties of the obscuring torus are directly coupled to this star formation, and that we should be thinking of the torus as a complex dynamical entity.

  18. The Keck OSIRIS Nearby AGN (KONA) Survey: AGN Fueling and Feedback

    NASA Astrophysics Data System (ADS)

    Hicks, Erin K. S.; Müller-Sánchez, Francisco; Malkan, Matthew A.; Yu, Po-Chieh

    In an effort to better constrain the relevant physical processes dictating the co-evolution of supermassive black holes and the galaxies in which they reside we turn to local Seyfert AGN. It is only with these local AGN that we can reach the spatial resolution needed to adequately characterize the inflow and outflow mechanisms thought to be the driving forces in establishing the relationship between black holes and their host galaxies at higher redshift. We present the first results from the KONA (Keck OSIRIS Nearby AGN) survey, which takes advantage of the integral field unit OSIRIS plus laser and natural guide star adaptive optics to probe down to scales of 5-30 parsecs in a sample of 40 local Seyfert galaxies. With these K-band data we measure the two-dimensional distribution and kinematics of the nuclear stars, molecular gas, and ionized gas within the central few hundred parsecs.

  19. Intermediate inclinations of type 2 Coronal-Line Forest AGN

    NASA Astrophysics Data System (ADS)

    Rose, Marvin; Elvis, Martin; Crenshaw, Michael; Glidden, Ana

    2015-07-01

    Coronal-Line Forest Active Galactic Nuclei (CLiF AGN) are remarkable in the sense that they have a rich spectrum of dozens of coronal emission lines (e.g. [Fe VII], [Fe X] and [Ne V]) in their spectra. Rose, Elvis & Tadhunter suggest that the inner obscuring torus wall is the most likely location of the coronal line region in CLiF AGN, and the unusual strength of the forbidden high-ionization lines is due to a specific AGN-torus inclination angle. Here, we test this suggestion using mid-IR colours (4.6-22 μm) from the Wide-Field Infrared Survey Explorer for the CLiF AGN. We use the Fischer et al. result that showed that as the AGN-torus inclination becomes more face on, the Spitzer 5.5-30 μm colours become bluer. We show that the [W2-W4] colours for the CLiF AGN (<[W2-W4]> = 5.92 ± 0.12) are intermediate between Sloan Digital Sky Survey (SDSS) type 1 (<[W2-W4]> = 5.22 ± 0.01) and type 2 AGN (<[W2-W4]> = 6.35 ± 0.03). This implies that the AGN-torus inclinations for the CLiF AGN are indeed intermediate, supporting the work of Rose, Elvis & Tadhunter. The confirmed relation between CLiF AGN and their viewing angle shows that CLiF AGN may be useful for our understanding of AGN unification.

  20. PRIMUS: The Relationship between Star Formation and AGN Accretion

    NASA Astrophysics Data System (ADS)

    Azadi, Mojegan; Aird, James; Coil, Alison L.; Moustakas, John; Mendez, Alexander J.; Blanton, Michael R.; Cool, Richard J.; Eisenstein, Daniel J.; Wong, Kenneth C.; Zhu, Guangtun

    2015-06-01

    We study the evidence for a connection between active galactic nuclei (AGNs) fueling and star formation by investigating the relationship between the X-ray luminosities of AGNs and the star formation rates (SFRs) of their host galaxies. We identify a sample of 309 AGNs with {10}41\\lt {L}X\\lt {10}44 erg s-1 at 0.2\\lt z\\lt 1.2 in the PRIMUS redshift survey. We find AGNs in galaxies with a wide range of SFR at a given LX. We do not find a significant correlation between SFR and the observed instantaneous LX for star-forming AGN host galaxies. However, there is a weak but significant correlation between the mean LX and SFR of detected AGNs in star-forming galaxies, which likely reflects that LX varies on shorter timescales than SFR. We find no correlation between stellar mass and LX within the AGN population. Within both populations of star-forming and quiescent galaxies, we find a similar power-law distribution in the probability of hosting an AGN as a function of specific accretion rate. Furthermore, at a given stellar mass, we find a star-forming galaxy ˜2-3 more likely than a quiescent galaxy to host an AGN of a given specific accretion rate. The probability of a galaxy hosting an AGN is constant across the main sequence of star formation. These results indicate that there is an underlying connection between star formation and the presence of AGNs, but AGNs are often hosted by quiescent galaxies.

  1. Ultra-fast outflows (aka UFOs) from AGNs and QSOs

    NASA Astrophysics Data System (ADS)

    Cappi, M.; Tombesi, F.; Giustini, M.

    During the last decade, strong observational evidence has been accumulated for the existence of massive, high velocity winds/outflows (aka Ultra Fast Outflows, UFOs) in nearby AGNs and in more distant quasars. Here we briefly review some of the most recent developments in this field and discuss the relevance of UFOs for both understanding the physics of accretion disk winds in AGNs, and for quantifying the global amount of AGN feedback on the surrounding medium.

  2. T cells, adhesion molecules and modulation of apoptosis in visceral leishmaniasis glomerulonephritis

    PubMed Central

    2010-01-01

    Background Immune complex deposition is the accepted mechanism of pathogenesis of VL glomerulopathy however other immune elements may participate. Further in the present study, no difference was seen between immunoglobulin and C3b deposit intensity in glomeruli between infected and non-infected dogs thus T cells, adhesion molecules and parameters of proliferation and apoptosis were analysed in dogs with naturally acquired VL from an endemic area. The dog is the most important domestic reservoir of the protozoa Leishmania (L.) chagasi that causes visceral leishmaniasis (VL). The similarity of VL manifestation in humans and dogs renders the study of canine VL nephropathy of interest with regard to human pathology. Methods From 55 dogs with VL and 8 control non-infected dogs from an endemic area, kidney samples were analyzed by immunohistochemistry for immunoglobulin and C3b deposits, staining for CD4+ and CD8+ T cells, ICAM-1, P-selectin and quantified using morphometry. Besides proliferation marker Ki-67, apoptosis markers M30 and TUNEL staining, and related cytokines TNF-α, IL-1α were searched and quantified. Results We observed similar IgG, IgM and IgA and C3b deposit intensity in dogs with VL and non-infected control dogs. However we detected the Leishmania antigen in cells in glomeruli in 54, CD4+ T cells in the glomeruli of 44, and CD8+ T cells in 17 of a total of 55 dogs with VL. Leishmania antigen was absent and T cells were absent/scarse in eight non-infected control dogs. CD 4+ T cells predominate in proliferative patterns of glomerulonephritis, however the presence of CD4+ and CD8+ T cells were not different in intensity in different patterns of glomerulonephritis. The expression of ICAM-1 and P-selectin was significantly greater in the glomeruli of infected dogs than in control dogs. In all patterns of glomerulonephritis the expression of ICAM-1 ranged from minimum to moderately severe and P-selectin from absent to severe. In the control animals the

  3. Antineutrophil Cytoplasmic Antibody-associated Vasculitis Superimposed on Infection-related Glomerulonephritis Secondary to Pulmonary Mycobacterium avium Complex Infection.

    PubMed

    Asano, Shuichi; Mizuno, Shige; Okachi, Shotaro; Aso, Hiromichi; Wakahara, Keiko; Hashimoto, Naozumi; Ito, Satoru; Kozaki, Yohei; Katsuno, Takayuki; Maruyama, Shoichi; Hasegawa, Yoshinori

    2016-01-01

    A 73-year-old woman was diagnosed with pulmonary Mycobacterium avium complex (MAC) infection and received no treatment. Disease progression was evident one year later with the development of myeloperoxidase-antineutrophil cytoplasmic antibody (ANCA) titers and systemic symptoms of a fever, polyarthritis, purpura, and rapidly progressive glomerulonephritis. Her symptoms did not improve with antibiotic treatment. A renal biopsy revealed crescentic glomerulonephritis with immunodeposition. According to these findings, she was diagnosed with ANCA-associated vasculitis (AAV) superimposed on infection-related glomerulonephritis (IRGN). Although there was a risk of aggravating an underlying infection, the combination therapy of corticosteroid and antibiotics improved AAV, IRGN, and even the lung radiological findings. To the best of our knowledge, this is the first case of AAV and IRGN secondary to pulmonary MAC infection. PMID:27580547

  4. Hot Dust Obscured Galaxies with Excess Blue Light: Dual AGN or Single AGN Under Extreme Conditions?

    NASA Astrophysics Data System (ADS)

    Assef, R. J.; Walton, D. J.; Brightman, M.; Stern, D.; Alexander, D.; Bauer, F.; Blain, A. W.; Diaz-Santos, T.; Eisenhardt, P. R. M.; Finkelstein, S. L.; Hickox, R. C.; Tsai, C.-W.; Wu, J. W.

    2016-03-01

    Hot dust-obscured galaxies (Hot DOGs) are a population of hyper-luminous infrared galaxies identified by the Wide-field Infrared Survey Explorer (WISE) mission from their very red mid-IR colors, and characterized by hot dust temperatures (T > 60 K). Several studies have shown clear evidence that the IR emission in these objects is powered by a highly dust-obscured active galactic nucleus (AGN) that shows close to Compton-thick absorption at X-ray wavelengths. Thanks to the high AGN obscuration, the host galaxy is easily observable, and has UV/optical colors usually consistent with those of a normal galaxy. Here we discuss a sub-population of eight Hot DOGs that show enhanced rest-frame UV/optical emission. We discuss three scenarios that might explain the excess UV emission: (i) unobscured light leaked from the AGN by reflection over the dust or by partial coverage of the accretion disk; (ii) a second unobscured AGN in the system; or (iii) a luminous young starburst. X-ray observations can help discriminate between these scenarios. We study in detail the blue excess Hot DOG WISE J020446.13-050640.8, which was serendipitously observed by Chandra/ACIS-I for 174.5 ks. The X-ray spectrum is consistent with a single, hyper-luminous, highly absorbed AGN, and is strongly inconsistent with the presence of a secondary unobscured AGN. Based on this, we argue that the excess blue emission in this object is most likely either due to reflection or a co-eval starburst. We favor the reflection scenario as the unobscured star formation rate needed to power the UV/optical emission would be ≳1000 M⊙ yr-1. Deep polarimetry observations could confirm the reflection hypothesis.

  5. A comparative study of AGN feedback algorithms

    NASA Astrophysics Data System (ADS)

    Wurster, J.; Thacker, R. J.

    2013-05-01

    Modelling active galactic nuclei (AGN) feedback in numerical simulations is both technically and theoretically challenging, with numerous approaches having been published in the literature. We present a study of five distinct approaches to modelling AGN feedback within gravitohydrodynamic simulations of major mergers of Milky Way-sized galaxies. To constrain differences to only be between AGN feedback models, all simulations start from the same initial conditions and use the same star formation algorithm. Most AGN feedback algorithms have five key aspects: the black hole accretion rate, energy feedback rate and method, particle accretion algorithm, black hole advection algorithm and black hole merger algorithm. All models follow different accretion histories, and in some cases, accretion rates differ by up to three orders of magnitude at any given time. We consider models with either thermal or kinetic feedback, with the associated energy deposited locally around the black hole. Each feedback algorithm modifies the region around the black hole to different extents, yielding gas densities and temperatures within r ˜ 200 pc that differ by up to six orders of magnitude at any given time. The particle accretion algorithms usually maintain good agreement between the total mass accreted by dot{M} dt and the total mass of gas particles removed from the simulation, although not all algorithms guarantee this to be true. The black hole advection algorithms dampen inappropriate dragging of the black holes by two-body interactions. Advecting the black hole a limited distance based upon local mass distributions has many desirably properties, such as avoiding large artificial jumps and allowing the possibility of the black hole remaining in a gas void. Lastly, two black holes instantly merge when given criteria are met, and we find a range of merger times for different criteria. This is important since the AGN feedback rate changes across the merger in a way that is dependent

  6. The AGN origin of cluster magnetic fields

    NASA Astrophysics Data System (ADS)

    Xu, Hao

    The origin of magnetic fields in galaxy clusters is one of the most fascinating but challenging problems in astrophysics. In this dissertation, the possibility of an Active Galactic Nucleus (AGN) origin of cluster magnetic fields is studied through state of the art simulations of magnetic field evolution in large scale structure formation using a newly developed cosmological Adaptive Mesh Refinement (AMR) Magnetohydrodynamics (MHD) code -- EnzoMHD. After presenting a complete but concise description and verification of the code, we discuss the creation of magnetic fields through the Biermann Battery effect during first star formation and galaxy cluster formation. We find that magnetic fields are produced as predicted by theory in both cases. For the first star formation, we obtain a lower limit of (~ 10 -9 G) for magnetic fields when the first generation stars form. On the other hand, we find that the magnetic energy is amplified 4 orders of magnitude within ~ 10 Gyr during cluster formation. We then study magnetic field injection from AGN into the Intra- Cluster Medium (ICM) and their impact on the ICM. We reproduce the X-ray cavities as well as weak shocks seen in observations in the simulation, and further confirm the idea that AGN outburst must contain lots of magnetic energy (up to 10 61 ergs) and the magnetic fields play an important part in the formation of jet/lobe system. We present high resolution simulations of cluster formation with magnetic fields injected from high redshift AGN. We find that these local magnetic fields are spread quickly throughout the whole cluster by cluster mergers. The ICM is in a turbulent state with a Kolmogorov-like power spectrum. Magnetic fields are amplified to and maintained at the observational level of a few mG by bulk flows at large scale and the ICM turbulence at small scale. The total magnetic energy increases about 25 times to ~ 1.2 × 10^61 ergs at the present time. We conclude that magnetic fields from AGN at high

  7. Novel Role of Toll-Like Receptor 3 in Hepatitis C-Associated Glomerulonephritis

    PubMed Central

    Wörnle, Markus; Schmid, Holger; Banas, Bernhard; Merkle, Monika; Henger, Anna; Roeder, Maximilian; Blattner, Simone; Bock, Elisabeth; Kretzler, Matthias; Gröne, Hermann-Josef; Schlöndorff, Detlef

    2006-01-01

    Hepatitis C virus (HCV) infection is frequently complicated by glomerulonephritis with immune complexes containing viral RNA. We examined the potential influence of Toll-like receptors (TLRs), specifically TLR3 recognition of viral dsRNA exemplified by polyriboinosinic:polyribocytidylic acid [poly(I:C) RNA]. Normal human kidney stained positive for TLR3 on mesangial cells (MCs), vascular smooth muscle cells, and collecting duct epithelium. Cultured MCs have low TLR3 mRNA levels with predominant intracellular protein localization, which was increased by tumor necrosis factor-α, interleukin (IL)-1β, interferon (IFN)-γ, and the TLR3 ligand poly(I:C) RNA. Poly(I:C) RNA stimulation of MCs increased mRNA and protein synthesis of IL-6, IL-1β, M-CSF, IL-8/CXCL8, RANTES/CCL5, MCP-1/CCL2, and ICAM-I; it also increased anti-proliferative and proapoptotic effects, the latter of which was decreased by inhibiting caspase-8. In microdissected glomeruli of normal and non-HCV membranoproliferative glomerulonephritis biopsies, TLR3 mRNA expression was low. In contrast TLR3 mRNA expression was significantly increased in hepatitis C-positive glomerulonephritis and was associated with enhanced mRNA for RANTES/CCL5 and MCP-1/CCL2. We hypothesize that immune complexes containing viral RNA activate mesangial TLR3 during HCV infection, thereby contributing to chemokine/cytokine release and effecting proliferation and apoptosis. Thus, TLR3 expression on renal cells, and especially MCs, may establish a link between viral infections and glomerular diseases. PMID:16436653

  8. The immunodominant myeloperoxidase T-cell epitope induces local cell-mediated injury in antimyeloperoxidase glomerulonephritis.

    PubMed

    Ooi, Joshua D; Chang, Janet; Hickey, Michael J; Borza, Dorin-Bogdan; Fugger, Lars; Holdsworth, Stephen R; Kitching, A Richard

    2012-09-25

    Microscopic polyangiitis is an autoimmune small-vessel vasculitis that often manifests as focal and necrotizing glomerulonephritis and renal failure. Antineutrophil cytoplasmic Abs (ANCAs) specific for myeloperoxidase (MPO) play a role in this disease, but the role of autoreactive MPO-specific CD4(+) T cells is uncertain. By screening overlapping peptides of 20 amino acids spanning the MPO molecule, we identified an immunodominant MPO CD4(+) T-cell epitope (MPO(409-428)). Immunizing C57BL/6 mice with MPO(409-428) induced focal necrotizing glomerulonephritis similar to that seen after whole MPO immunization, when MPO was deposited in glomeruli. Transfer of an MPO(409-428)-specific CD4(+) T-cell clone to Rag1(-/-) mice induced focal necrotizing glomerulonephritis when glomerular MPO deposition was induced either by passive transfer of MPO-ANCA and LPS or by planting MPO(409-428) conjugated to a murine antiglomerular basement membrane mAb. MPO(409-428) also induced biologically active anti-MPO Abs in mice. The MPO(409-428) epitope has a minimum immunogenic core region of 11 amino acids, MPO(415-426), with several critical residues. ANCA-activated neutrophils not only induce injury but lodged the autoantigen MPO in glomeruli, allowing autoreactive anti-MPO CD4(+) cells to induce delayed type hypersensitivity-like necrotizing glomerular lesions. These studies identify an immunodominant MPO T-cell epitope and redefine how effector responses can induce injury in MPO-ANCA-associated microscopic polyangiitis. PMID:22955884

  9. IgA-dominant post-infectious glomerulonephritis presenting as a fatal pulmonary-renal syndrome.

    PubMed

    Saad, Marc; Daoud, Magda; Nasr, Patricia; Syed, Rafeel; El-Sayegh, Suzanne

    2015-01-01

    Over the last decades, post-infectious glomerulonephritis underwent major changes in its epidemiology, pathophysiology, and outcomes. We are reporting a case of IgA-dominant post-infectious glomerulonephritis (IgA-PIGN) presenting as a fatal pulmonary-renal syndrome. An 86-year-old Filipino man presented with worsening dyspnea, hemoptysis, and decreased urine output over 2 weeks. Past medical history is significant for hypertension, chronic kidney disease stage III, and pneumonia 3 weeks prior treated with intravenous cefazolin for methicillin-sensitive Staphylococcus aureus bacteremia. Physical examination was remarkable for heart rate of 109/min and respiratory rate of 25/min saturating 99% on 3 liters via nasal cannula. There were bibasilar rales in the lungs and bilateral ankle edema. A chest radiograph showed bibasilar opacifications. Blood work was significant for hemoglobin of 8.3 g/dL and creatinine of 9.2 mg/dL (baseline of 1.67). TTE showed EF 55%. Urinalysis revealed large blood and red blood cell casts. Kidney ultrasound showed bilateral echogenicity compatible with renal disease. Pulse methylprednisolone therapy and hemodialysis were initiated with patient's condition precluding kidney biopsy. Serology workup for rapidly progressive glomerulonephritis was negative. On day 7, the patient required mechanical ventilation; bronchoscopy showed alveolar hemorrhage and plasmapheresis was initiated. Renal biopsy revealed IgA-PIGN with endocapillary and focal extracapillary proliferative and exudative features. IgA-PIGN occurs in diabetic elderly (mean age of 60 years), 0-16 weeks after an infection mainly by Staphylococcus. However, this nondiabetic patient had normal complement IgA-PIGN with fatal pulmonary-renal syndrome. Understanding the pathogenesis and identifying the nephrotoxic bacteria species and the aberrant IgA molecule will open new insights toward prevention and treatment. PMID:26347210

  10. IgA-dominant post-infectious glomerulonephritis presenting as a fatal pulmonary-renal syndrome

    PubMed Central

    Saad, Marc; Daoud, Magda; Nasr, Patricia; Syed, Rafeel; El-Sayegh, Suzanne

    2015-01-01

    Over the last decades, post-infectious glomerulonephritis underwent major changes in its epidemiology, pathophysiology, and outcomes. We are reporting a case of IgA-dominant post-infectious glomerulonephritis (IgA-PIGN) presenting as a fatal pulmonary-renal syndrome. An 86-year-old Filipino man presented with worsening dyspnea, hemoptysis, and decreased urine output over 2 weeks. Past medical history is significant for hypertension, chronic kidney disease stage III, and pneumonia 3 weeks prior treated with intravenous cefazolin for methicillin-sensitive Staphylococcus aureus bacteremia. Physical examination was remarkable for heart rate of 109/min and respiratory rate of 25/min saturating 99% on 3 liters via nasal cannula. There were bibasilar rales in the lungs and bilateral ankle edema. A chest radiograph showed bibasilar opacifications. Blood work was significant for hemoglobin of 8.3 g/dL and creatinine of 9.2 mg/dL (baseline of 1.67). TTE showed EF 55%. Urinalysis revealed large blood and red blood cell casts. Kidney ultrasound showed bilateral echogenicity compatible with renal disease. Pulse methylprednisolone therapy and hemodialysis were initiated with patient’s condition precluding kidney biopsy. Serology workup for rapidly progressive glomerulonephritis was negative. On day 7, the patient required mechanical ventilation; bronchoscopy showed alveolar hemorrhage and plasmapheresis was initiated. Renal biopsy revealed IgA-PIGN with endocapillary and focal extracapillary proliferative and exudative features. IgA-PIGN occurs in diabetic elderly (mean age of 60 years), 0–16 weeks after an infection mainly by Staphylococcus. However, this nondiabetic patient had normal complement IgA-PIGN with fatal pulmonary-renal syndrome. Understanding the pathogenesis and identifying the nephrotoxic bacteria species and the aberrant IgA molecule will open new insights toward prevention and treatment. PMID:26347210

  11. Identifying Luminous AGN in Deep Surveys: Revised IRAC Selection Criteria

    NASA Astrophysics Data System (ADS)

    Donley, Jennifer; Koekemoer, A. M.; Brusa, M.; Capak, P.; Cardamone, C. N.; Civano, F.; Ilbert, O.; Impey, C. D.; Kartaltepe, J.; Miyaji, T.; Salvato, M.; Sanders, D. B.; Trump, J. R.; Zamorani, G.

    2012-01-01

    Spitzer IRAC selection is a powerful tool for identifying luminous AGN. The AGN selection wedges currently in use, however, are heavily contaminated by star-forming galaxies, especially at high redshift. Using the large samples of luminous AGN and high-redshift star-forming galaxies in COSMOS, we redefine the AGN selection criteria for use in deep IRAC surveys. The new IRAC criteria are designed to be both highly complete and reliable, and incorporate the best aspects of the current AGN selection wedges and of infrared power-law selection while excluding high redshift star-forming galaxies selected via the BzK, DRG, LBG, and SMG criteria. At QSO-luminosities of log L(2-10 keV)>44, the new IRAC criteria recover 75% of the hard X-ray and IRAC-detected XMM-COSMOS sample, yet only 37% of the IRAC AGN candidates have X-ray counterparts, a fraction that rises to 51% in regions with Chandra exposures of 50-160 ks. X-ray stacking of the individually X-ray non-detected AGN candidates leads to a hard X-ray signal indicative of heavily obscured to mildly Compton-thick obscuration (log NH >= 23.7). While IRAC selection recovers a substantial fraction of luminous unobscured and obscured AGN, it is incomplete to low-luminosity and host-dominated AGN.

  12. AGN Variability Surveys: DASCH from BATSS to EXIST

    NASA Astrophysics Data System (ADS)

    Grindlay, J. E.

    2007-10-01

    Active galactic nuclei (AGN) are variable on a wide range of timescales. Combined with their redshifts and thus luminosity, variability was of course instrumental in their initial identification with accretion onto supermassive black holes. Previous broad-band (both spectral and temporal) variability surveys of AGN are limited in their temporal and spectral bandwidth, despite their promise for probing the central engine and black hole mass. We provide a brief summary of three new AGN variability surveys, two (BATSS and DASCH) about to begin and the third (EXIST) possible within the next decade, which will open new windows on the physics and fundamental properties of AGN.

  13. Investigating The AGN Population In Cluster Environments Across Different Wavelengths

    NASA Astrophysics Data System (ADS)

    Byler, Eleanor; Norman, D.

    2011-01-01

    Currently, there is no complete picture of AGN formation and evolution in galaxy clusters. A general understanding of the AGN population has been impeded by cluster and selection biases and recent studies have shown that there is a large population of obscured or optically unremarkable AGN in galaxy clusters. We used SDSS data to look at the AGN distribution in 12 clusters over a range of redshifts (z = 0.16 - 0.35) and compared the optical and X-ray AGN content with that of six `blank’ fields. We found that on average the cluster fields had a small optical AGN excess as compared to blank fields. The AGN population and distribution was also compared by cluster morphology, and non-virialized clusters were found to have a higher X-ray and optical AGN content than virialized clusters. We also compare our optical AGN to Gilmour et al.'s (2009) X-ray survey to compare assumptions made about cluster membership. Byler was supported by the NOAO/KPNO Research Experiences for Undergraduates (REU) Program, which is funded by the National Science Foundation Research Experiences for Undergraduates Program and the Department of Defense ASSURE program through Scientific Program Order No. 13 (AST-0754223) of the Cooperative Agreement No. AST-0132798 between the Association of Universities for Research in Astronomy (AURA) and the NSF.

  14. Are the hosts of VLBI-selected radio-AGN different to those of radio-loud AGN?

    NASA Astrophysics Data System (ADS)

    Rees, G. A.; Norris, R. P.; Spitler, L. R.; Herrera-Ruiz, N.; Middelberg, E.

    2016-05-01

    Recent studies have found that radio-AGN selected by radio-loudness show little difference in terms of their host galaxy properties when compared to non-AGN galaxies of similar stellar mass and redshift. Using new 1.4 GHz very long baseline interferometry (VLBI) observations of the Cosmological Evolution Survey field, we find that approximately 49 ± 8 per cent of high-mass (M > 1010.5 M⊙), high-luminosity (L1.4 > 1024 W Hz-1) radio-AGN possess a VLBI-detected counterpart. These objects show no discernible bias towards specific stellar masses, redshifts or host properties other than what is shown by the radio-AGN population in general. Radio-AGN that are detected in VLBI observations are not special, but form a representative sample of the radio-loud AGN population.

  15. Clinical spectrum and outcomes of crescentic glomerulonephritis: A single center experience

    PubMed Central

    Rampelli, S. K.; Rajesh, N. G.; Srinivas, B. H.; Harichandra Kumar, K. T.; Swaminathan, R. P.; Priyamvada, P. S.

    2016-01-01

    There is limited data on the etiology, clinical and histopathological spectrum and outcomes of crescentic glomerulonephritis (CrGN) in adult Indian population. This prospective study was done to evaluate the etiology, clinicohistological patterns and predictors of outcome of CrGN in South Indian population. All the patients received standard protocol based immunosuppression in addition to supportive care. Immune-complex glomerulonephritis (ICGN) was the most common etiology (n = 31; 77.5%) followed by pauci-immune glomerulonephritis (PauciGN; n = 8; 20%) and anti-glomerular basement membrane disease (n = 1; 2.5%). The most common etiology of ICGN was IgA nephropathy (n = 11; 27.5%) followed by lupus nephritis (n = 7; 17.5%) and post-infectious glomerulonephritis (PIGN) (n = 7; 17.5%). The patients with PauciGN were significantly older compared to those with ICGN (44.5 ± 15 years vs. 31.8 ± 11 years; P = 0.01). The patients with PauciGN presented with significantly higher serum creatinine (9.7 ± 4.4 vs. 6.6 ± 3.3 mg/dl; P = 0.03). The histopathologic parameters of ICGN and PauciGN were comparable except for a higher proportion of sclerosed glomeruli in ICGN. At the end of 3 months follow-up, only two patients went into complete remission (5.4%). Majority of the patients had end-stage renal failure (48.6%) and were dialysis dependent and seven patients (18.9%) expired. There was no signifi difference in the renal survival (10.9 ± 1.9 vs. 9.6 ± 3.3 months) or patient survival (17.5 ± 2.1 vs. 17.3 ± 4.3 months). The parameters associated with adverse outcomes at 3 months were hypertension (odds ratio [OR]: 0.58; confidence interval [CI]: 0.36–0.94), need for renal replacement therapy (OR: 0.19; CI: 0.04–0.9), serum creatinine at admission (P = 0.019), estimated glomerular filtration rate (P = 0.022) and percentage of fibrocellular crescents (P = 0.022). PMID:27512296

  16. Clinical spectrum and outcomes of crescentic glomerulonephritis: A single center experience.

    PubMed

    Rampelli, S K; Rajesh, N G; Srinivas, B H; Harichandra Kumar, K T; Swaminathan, R P; Priyamvada, P S

    2016-01-01

    There is limited data on the etiology, clinical and histopathological spectrum and outcomes of crescentic glomerulonephritis (CrGN) in adult Indian population. This prospective study was done to evaluate the etiology, clinicohistological patterns and predictors of outcome of CrGN in South Indian population. All the patients received standard protocol based immunosuppression in addition to supportive care. Immune-complex glomerulonephritis (ICGN) was the most common etiology (n = 31; 77.5%) followed by pauci-immune glomerulonephritis (PauciGN; n = 8; 20%) and anti-glomerular basement membrane disease (n = 1; 2.5%). The most common etiology of ICGN was IgA nephropathy (n = 11; 27.5%) followed by lupus nephritis (n = 7; 17.5%) and post-infectious glomerulonephritis (PIGN) (n = 7; 17.5%). The patients with PauciGN were significantly older compared to those with ICGN (44.5 ± 15 years vs. 31.8 ± 11 years; P = 0.01). The patients with PauciGN presented with significantly higher serum creatinine (9.7 ± 4.4 vs. 6.6 ± 3.3 mg/dl; P = 0.03). The histopathologic parameters of ICGN and PauciGN were comparable except for a higher proportion of sclerosed glomeruli in ICGN. At the end of 3 months follow-up, only two patients went into complete remission (5.4%). Majority of the patients had end-stage renal failure (48.6%) and were dialysis dependent and seven patients (18.9%) expired. There was no signifi difference in the renal survival (10.9 ± 1.9 vs. 9.6 ± 3.3 months) or patient survival (17.5 ± 2.1 vs. 17.3 ± 4.3 months). The parameters associated with adverse outcomes at 3 months were hypertension (odds ratio [OR]: 0.58; confidence interval [CI]: 0.36-0.94), need for renal replacement therapy (OR: 0.19; CI: 0.04-0.9), serum creatinine at admission (P = 0.019), estimated glomerular filtration rate (P = 0.022) and percentage of fibrocellular crescents (P = 0.022). PMID:27512296

  17. Characterization of feline glomerulonephritis associated with viral-induced hematopoietic neoplasms.

    PubMed

    Glick, A D; Horn, R G; Holscher, M

    1978-08-01

    Light, electron, and immunofluorescence microscopy on tissues from 63 domestic cats revealed that glomerulonephritis occurred in almost one third of cats with hematopoietic neoplasms of the type linked with feline leukemia virus (FeLV). Glomerular lesions were of the immune complex type with subepithelial, subendothelial, and mesangial dense deposits and reticular aggregates, similar to the nephropathy associated with systemic lupus erythematosus in humans. Evidence that the glomerular lesions may be viral-induced raises the possibility of similar pathogenetic mechanisms in human disease. PMID:677265

  18. Intestinal Intravascular Large B-cell Lymphoma Mimicking Ulcerative Colitis with Secondary Membranoproliferative Glomerulonephritis.

    PubMed

    Kaneyuki, Daisuke; Komeno, Yukiko; Yoshimoto, Hiroshi; Yoshimura, Naoki; Iihara, Kuniko; Ryu, Tomiko

    2016-01-01

    A 47-year-old woman with ulcerative colitis (UC) was admitted to our hospital for renal dysfunction and progressive anemia. Colonoscopy revealed intestinal lesions and pathological findings showed intravascular large B-cell lymphoma (IVLBCL). According to the polymerase chain reaction analysis of sequential rectal specimens, we concluded that she suffered from intestinal BCL, not UC. After chemotherapy, her renal function progressed to nephrotic syndrome. The pathological findings of renal biopsy specimens indicated membranoproliferative glomerulonephritis (MPGN). Chemotherapy was continued and led to the remission of BCL and MPGN. We herein describe the first case of intestinal IVLBCL mimicking UC with secondary MPGN. PMID:27580553

  19. Hydralazine-induced pauci-immune glomerulonephritis: intriguing case series with misleading diagnoses

    PubMed Central

    Babar, Faizan; Posner, Jeffery N.; Obah, Eugene A.

    2016-01-01

    Hydralazine has been used since the 1950s for the management of hypertension. Evidence for hydralazine-associated vasculitis dates to pre-ANCA (antineutrophil cytoplasmic antibodies) era. This abstract describes two cases of ANCA-positive pauci-immune glomerulonephritis (GN) in challenging scenarios where diagnosis was misconstrued. A comprehensive literature review was done to understand the pathogenesis of drug-induced pauci-immune GN. We have described key diagnostic features that are helpful in distinguishing idiopathic ANCA vasculitis from drug-induced vasculitis. Additionally, we have also described different treatments meant to provide therapy options with the least side effects. PMID:27124161

  20. Renal granuloma and immunoglobulin M-complex glomerulonephritis: a case of common variable immunodeficiency?

    PubMed

    Benoit, Geneviève; Lapeyraque, Anne-Laure; Sartelet, Hervé; Saint-Cyr, Claire; Le Deist, Françoise; Haddad, Elie

    2009-03-01

    Common variable immunodeficiency (CVID) is characterized by reduced serum immunoglobulin levels and recurrent bacterial infections. Granulomatous infiltrations are occasionally found in the lymphoid or solid organs of affected patients, but renal involvement is rare. We present a case of possible CVID with interstitial noncaseating granuloma and immunoglobulin (IgM)-complex glomerulonephritis with a membranoproliferative pattern and with a favorable response to corticosteroids, intravenously administered immunoglobulins (IVIGs) and rituximab. CVID must be included in the differential diagnosis of renal granuloma and should be differentiated from sarcoidosis to ensure appropriate therapy. PMID:18696117

  1. Necrotizing and crescentic glomerulonephritis with membranous nephropathy in a patient exposed to levamisole-adulterated cocaine

    PubMed Central

    Carrara, Camillo; Emili, Stefano; Lin, Mercury; Alpers, Charles E.

    2016-01-01

    Levamisole is an antihelminthic agent widely used as an adulterant of illicit cocaine recently implicated as a cause of antineutrophil cytoplasmic antibody (ANCA)–associated microscopic polyangiitis in cocaine abusers. An isolated case of membranous nephropathy (MN) associated with levamisole exposure has also been reported. We report the first case, to our knowledge, of a patient with both microscopic polyangiitis manifest as a pauci-immune necrotizing and crescentic glomerulonephritis and concurrent MN in the setting of chronic cocaine abuse and presumed levamisole exposure, raising the hypothesis that levamisole was the causative agent in the development of this rare dual glomerulopathy. PMID:26985374

  2. Membranous glomerulonephritis and cellular crescents induced by levamisole-adulterated cocaine abuse: a case report

    PubMed Central

    Moll-Guillen, Jose-Luis; Espí-Reig, Jordi; Blanes-Julia, Marino; García-Martínez, Ana-María; Pujol-Marco, Conrad; Hernández-Jaras, Julio

    2015-01-01

    Levamisole is illicitly employed as a cocaine adulterant. The consumption of levamisole-adulterated cocaine can provoke anti-neutrophil cytoplasmic antibody (ANCA)-associated syndromes. Patients carrying an HLAB27 allele are known to be at higher risk of developing agranulocytosis when treated with levamisole. Likewise, patients with ANCA-associated vasculitis (AAV) and internal organ involvement have typically been exposed to offending agents for prolonged periods of time, often on the order of years. Here, we report an unusual case of a patient in which kidney biopsy showed membranous glomerulonephritis with cellular crescents associated with levamisole-contaminated cocaine use. PMID:26605317

  3. Nephrotic Syndrome Secondary to Proliferative Glomerulonephritis with Monoclonal Immunoglobulin Deposits of Lambda Light Chain

    PubMed Central

    Yun, Seongseok; Braunhut, Beth L.; Walker, Courtney N.; Bhati, Waheed; Sussman, Amy N.; Anwer, Faiz

    2014-01-01

    We describe a rare case of a 46-year-old woman with history of refractory nephrotic syndrome and hypertension who presented with worsening proteinuria and kidney function. Work-up for both autoimmune and infectious diseases and hematologic malignancies including multiple myeloma were negative. Kidney biopsy demonstrated glomerular sclerotic change with lambda light chain deposits in the subendothelial space, which is consistent with proliferative glomerulonephritis with monoclonal immunoglobulin deposit (PGNMID). The patient was treated with bortezomib and dexamethasone without clinical improvement and eventually became hemodialysis dependent. PMID:25136462

  4. Antineutrophil Cytoplasmic Antibodies-Negative Pauci-Immune Crescentic Glomerulonephritis Associated with Multiple Myeloma

    PubMed Central

    Anaele, Cyriacus Uzoma; Srisung, Weeraporn; Tomacruz, Yvette; Laski, Melvin

    2015-01-01

    Pauci-immune crescentic glomerulonephritis (PICGN) is most commonly associated with antineutrophil cytoplasmic antibodies (ANCA). We report a case of chronic, sclerosing ANCA-negative PICGN discovered when a patient presented with multiple myeloma. A 57-year-old woman presented with complaints of nausea, emesis and weakness. She was found to be in renal failure with a serum creatinine of 9.4 mg/dl, mild hyperkalemia and acidosis. She was noted to have normochromic, normocytic anemia with normal platelet and white cell counts, normal plasma proteins and serum protein electrophoresis. Further studies revealed increased concentrations of κ and λ light chains in a ratio of 34.89; a bone marrow biopsy found 12% plasma cells. Serum protein electrophoresis revealed no spike. ANCA, anti-glomerular basement membrane, antineutrophil antibody, hepatitis panel and serum complements were normal. A kidney biopsy result showed chronic sclerosing PICGN plus tubular necrosis, severe tubular atrophy, interstitial fibrosis and severe arteriosclerosis. Congo red stains were negative and electron microscopy showed no intraglomerular deposits. The patient was subsequently treated for myeloma with bortezomib and dexamethasone with good hematologic response but never recovered renal function. She remains on outpatient hemodialysis. Renal manifestations of myeloma often involve glomerular deposition disease, tubulointerstitial disease, with characteristic proteinaceous casts, or both. In contrast, our patient demonstrated neither of these findings but had chronic sclerosing PICGN. Crescentic glomerulonephritis occurring in patients with plasma cell dyscrasias has been previously reported, but the association remains extremely rare. PMID:26120578

  5. Spontaneous remission of membranous glomerulonephritis with successful fetal outcome: A case report and literature review.

    PubMed

    Huang, Yan-Mei; Zhou, Hui-Rong; Zhang, Ling; Yang, Ke-Ke; Luo, Jiang-Xi; Zhao, Hai-Lu

    2016-06-01

    Membranous glomerulonephritis (MGN) represents an immunologically mediated disease characterized by deposition of immune complexes in the glomerular subepithelial space. Persistent proteinuria at diagnosis predicts poor prognosis. Pregnancy with MGN is a risk of fetal loss and may worsen maternal renal function.Here, we report a lady with MGN and proteinuria achieved spontaneous remission and successful fetal outcome naive to any medications. The 26-year old woman had 1-year history of persistent proteinuria (5.5-12.56 g/24 hours) and biopsy-proven MGN. Histopathological characteristics included glomerular basement membrane spikes, subepithelial monoclonal IgG immunofluorescence, and diffuse electron dense deposits. She was sticking to a regular morning exercise routine without any medications. After successful delivery of a full-term baby girl, the mother had improved proteinuria (0.56 g/24 hours) and albuminuria (351.96 g/24 hours contrasting 2281.6 g/24 hours before pregnancy). The baby had normal height and body weight at 4 months old.We identified more pregnancies with MGN in 5 case reports and 5 clinical series review articles (7-33 cases included). Spontaneous remission of maternal MGN with good fetal outcome rarely occurred in mothers on immunosuppressive therapy.Mothers naive to immunosuppressive therapy may achieve spontaneous remission of maternal membranous glomerulonephritis and successful fetal outcome. Theoretically, fetus might donate stem cells to heal mother's kidney. PMID:27368022

  6. The changing pattern of primary glomerulonephritis in Singapore and other countries over the past 3 decades.

    PubMed

    Woo, K-T; Chan, C-M; Mooi, C Y; -L-Choong, H; Tan, H-K; Foo, M; Lee, G S L; Anantharaman, V; Lim, C-H; Tan, C-C; Lee, E J C; Chiang, G S C; Tan, P H; Boon, T H; Fook-Chong, S; Wong, K-S

    2010-11-01

    This review of 2,586 renal biopsies over the past 3 decades in Singapore documents the changing pattern of glomerulonephritis (GN) from that of a third world country to that of a developed nation. In the 1st decade, mesangial proliferative glomerulonephritis was the most common form of primary GN, just as it was in the surrounding Asian countries. In the 2nd decade, the prevalence of mesangial proliferative GN decreased with a rise in membranous, GN which is also seen in China and Thailand. In the 3rd decade, there was a dramatic increase in focal sclerosing glomerulosclerosis. This increase reflects aging and obesity in keeping with more developed countries like Australia, India, Thailand and the United States of America. IgA nephritis remains the most common GN. Apart from the geographical influence, other socioeconomic factors play a significant role in the evolution of the renal biopsy pattern. Mesangial proliferative GN remains prevalent in many Asian countries, but in Singapore the prevalence is decreasing just as it is in Japan, Korea and Malaysia. Worldwide, the prevalence of focal sclerosing glomerulosclerosis continues to increase in many countries. PMID:20979946

  7. CD34+ fibroblast-like cells in the interstitial infiltrates in glomerulonephritis - an immunohistochemical observation.

    PubMed

    Gluhovschi, Cristina; Potencz, Elena; Lazar, Elena; Petrica, Ligia; Bozdog, Gheorghe; Gadalean, Florica; Bob, Flaviu; Gluhovschi, Adrian; Cioca, Daniel; Velciov, Silvia

    2012-12-01

    CD34 cells in the interstitial infiltrates in glomerulonephritis (GN) could be the turning point between regenerative processes and interstitial fibrosis. The aim of our study was to assess the presence of CD34+ cells in the interstitial infiltrates in GN. A cross-sectional study of 33 patients with glomerulonephritis, mean age: 43.3 ±11.31 years, 20 male and 13 female, was conducted. Conventional stains, as well as immunohistochemistry for the CD34 antigen were employed on kidney biopsies. Strength of immunohistochemical reaction was assessed semi-quantitatively. Regarding the percentage of cases with CD34+ cells in the interstitial infiltrates out of 33 patients: cells of interstitial infiltrates were 27.3% positive. The percentage of cases showing CD34+ cells at the level of interstitial infiltrates was: 44.4% in FSGS, 14.3% in membranoproliferative GN, 28.6% in membranous nephropathy, 20% in mesangial proliferative GN, 0% in minimal change disease, and 50% in crescentic GN. With the exception of minimal change disease, CD34+ cells were found in the interstitial infiltrates in all histopathological forms of GN. Some of these cells were spindle-shaped fibroblast-like cells. As inflammation in the tubulointerstitial compartment either resolves or proceeds to fibrosis, aims at reversing this process will benefit from analyses of the interstitial infiltrates harboring CD34+ cells. PMID:23359197

  8. Hydrocarbon exposure may cause glomerulonephritis and worsen renal function: evidence based on Hill's criteria for causality.

    PubMed

    Ravnskov, U

    2000-08-01

    Many observational and experimental studies point to hydrocarbon exposure as an important pathogenic factor in glomerulonephritis. The findings have made little impact on current concepts and patient care, possibly because the hypothesis of a direct causal effect of the exposure and the hypothesis that the exposure worsens renal function have not been considered separately. This review examines these two hypotheses using Hill's criteria for causality. The results from 14 cross-sectional, 18 case-control studies, two cohort studies, 15 experiments on laboratory animals and two on human beings together with many case reports satisfy all but one of Hill's criteria for both hypotheses. Of particular importance is the finding in the case-control and follow-up studies of an association between degree of exposure and stage of renal disease, and an inverse association between degree of exposure and renal function, indicating that the most important effect of hydrocarbon exposure is its effect on renal function. End-stage renal failure may be preventable in many patients with glomerulonephritis provided a possible exposure to toxic chemicals is discontinued. PMID:10924538

  9. Antineutrophil Cytoplasmic Antibodies-Negative Pauci-Immune Crescentic Glomerulonephritis Associated with Multiple Myeloma.

    PubMed

    Anaele, Cyriacus Uzoma; Srisung, Weeraporn; Tomacruz, Yvette; Laski, Melvin

    2015-01-01

    Pauci-immune crescentic glomerulonephritis (PICGN) is most commonly associated with antineutrophil cytoplasmic antibodies (ANCA). We report a case of chronic, sclerosing ANCA-negative PICGN discovered when a patient presented with multiple myeloma. A 57-year-old woman presented with complaints of nausea, emesis and weakness. She was found to be in renal failure with a serum creatinine of 9.4 mg/dl, mild hyperkalemia and acidosis. She was noted to have normochromic, normocytic anemia with normal platelet and white cell counts, normal plasma proteins and serum protein electrophoresis. Further studies revealed increased concentrations of κ and λ light chains in a ratio of 34.89; a bone marrow biopsy found 12% plasma cells. Serum protein electrophoresis revealed no spike. ANCA, anti-glomerular basement membrane, antineutrophil antibody, hepatitis panel and serum complements were normal. A kidney biopsy result showed chronic sclerosing PICGN plus tubular necrosis, severe tubular atrophy, interstitial fibrosis and severe arteriosclerosis. Congo red stains were negative and electron microscopy showed no intraglomerular deposits. The patient was subsequently treated for myeloma with bortezomib and dexamethasone with good hematologic response but never recovered renal function. She remains on outpatient hemodialysis. Renal manifestations of myeloma often involve glomerular deposition disease, tubulointerstitial disease, with characteristic proteinaceous casts, or both. In contrast, our patient demonstrated neither of these findings but had chronic sclerosing PICGN. Crescentic glomerulonephritis occurring in patients with plasma cell dyscrasias has been previously reported, but the association remains extremely rare. PMID:26120578

  10. Revisiting post-infectious glomerulonephritis in the emerging era of C3 glomerulopathy

    PubMed Central

    Khalighi, Mazdak A.; Wang, Shihtien; Henriksen, Kammi J.; Bock, Margret; Keswani, Mahima; Meehan, Shane M.; Chang, Anthony

    2016-01-01

    Background Post-infectious glomerulonephritis (PIGN) is an immune complex-mediated glomerular injury that typically resolves. Dominant C3 deposition is characteristic of PIGN, but with the emergence of C3 glomerulonephritis (C3GN) as a distinct entity, it is unclear how the pathologic similarities between PIGN and C3GN should be reconciled. Therefore, nephrologists and nephropathologists need additional guidance at the time of biopsy. Methods We studied 23 pediatric and young adult patients diagnosed with PIGN. Patients were divided into two groups, one with co-dominance between C3 and immunoglobulins and the other meeting proposed diagnostic criteria for C3GN. Clinical and pathological features were compared. Results No clinical and/or pathological features could distinguish between those with C3-co-dominant deposits and those with C3 dominance. Nearly all patients in both groups regained their baseline renal function without clinical intervention. Conclusions Although the identification of abnormalities of the alternative pathway of complement is characteristic of C3GN, testing is not widely available and the turnaround time often exceeds 1 month. Our study found that PIGN with either co-dominant or dominant C3 deposition in a cohort of young patients has excellent short-term outcomes. Close clinical observation for persistent abnormalities, such as hypocomplementemia, prolonged hematuria or proteinuria, is recommended to single out patients that may harbor intrinsic complement abnormalities. PMID:27274823

  11. The role of Th1 and Th17 cells in glomerulonephritis

    PubMed Central

    Azadegan-Dehkordi, Fatemeh; Bagheri, Nader; Shirzad, Hedayatollah; Rafieian-Kopaei, Mahmoud

    2015-01-01

    Context: T helper (Th) cells as an important part of the immune is responsible for elimination of invading pathogens. But, if Th cell responses are not regulated effectively, the autoimmune diseases might develop. The Th17 subset usually produces interleukin-17A which in experimental models of organ-specific autoimmune inflammation is very important. Evidence Acquisitions: Directory of open access journals (DOAJ), Google Scholar, Embase, Scopus, PubMed and Web of Science have been searched. Results: Fifty-six articles were found and searched. In the present review article, we tried to summarize the recently published data about characteristics and role of Th1 and Th17 cells and discuss in detail, the potential role of these T helpers immune responses in renal inflammation and renal injury, focusing on glomerulonephritis. Published papers in animal and human studies indicated that autoimmune diseases such as rheumatoid arthritis and multiple sclerosis, classically believed to be Th1-mediated, are mainly derived from a Th17 immune response. Identification of the Th17 subgroup has explained seemingly paradoxical observations and improved our understanding of immune-mediated inflammatory responses. Conclusions: Secretion of IL-17A, as well as IL-17F, IL-21, IL-22, suggests that Th17 subset may play a crucial role as a pleiotropic pro-inflammatory Th subset. There is experimental evidence to support the notion that Th1 and Th17 cells contribute to kidney injury in renal inflammatory diseases like glomerulonephritis. PMID:25964886

  12. A case of infectious endocarditis-associated crescentic glomerulonephritis with intracranial hemorrhage.

    PubMed

    Miyata, Eri; Nakayama, Masaru; Amano, Kazushi; Hirano, Tadashi; Uesugi, Noriko

    2010-01-01

    A 55-year-old woman was admitted to our hospital because of fever and renal impairment. The patient had undergone a tooth extraction 11 months prior to admission. Echocardiography demonstrated vegetation on the mitral valve, and Streptococcus mitis was detected on blood culture. Accordingly, infectious endocarditis (IE) was diagnosed. Renal biopsy showed crescentic glomerulonephritis. Based on the negative staining for immunoglobulins and complement components in immunofluorescence study and lack of dense deposits on electron microscopy, the renal involvement was considered to be of the pauci-immune type. Subarachnoid hemorrhage (SAH) and subdural hematoma (SDH) developed simultaneously following commencement of antibiotic therapy. The intracranial involvement improved by conservative therapy. Antibiotic treatment resulted in gradual control of IE infection and improvement of renal function. A repeated renal biopsy, performed about 5 months after the first biopsy, showed amelioration of glomerular injury and interstitial damage. To our knowledge, our case was the second to report simultaneous developments of both SAH and SDH secondary to IE. We postulate that the glomerular injury was associated with IE. We report here a rare case of IE-associated crescentic glomerulonephritis with complications of SAH and SDH. PMID:20155718

  13. Renal infarction and immune-mediated glomerulonephritis in sheep (Ovis aries) chronically implanted with indwelling catheters.

    PubMed

    Rao, Varada P; Poutahidis, Theofilos; Marini, Robert P; Holcombe, Hilda; Rogers, Arlin B; Fox, James G

    2006-07-01

    Microbial infections are common sequelae in humans and animals implanted with long-term intravascular catheters. Understanding the pathophysiology of infectious morbidity is critical to improving quality of care in catheterized subjects. Here, we describe findings in 6 clinically healthy, male sheep implanted with indwelling aortic or cardiac catheters for 6 to 10 mo. We isolated multiple bacterial species including Serratia spp., Enterobacter agglomerans, Eschericia coli, Klebsiella oxytoca, and K. pneumoniae in aerobic cultures from catheter tips. Although sheep were clinically asymptomatic, 1 or both kidneys from all animals contained wedge-shaped infarcts of varying size and number. Microscopic examination revealed (a) marked fibrosis with mild inflammatory cell infiltrate consistent with chronic foreign body reaction around catheters; (b) moderate to severe, diffuse, subacute to chronic membranoproliferative glomerulonephritis and mild, multifocal chronic interstitial nephritis; and (c) mesangial immune-complex deposition as demonstrated by direct immunofluorescence technique. The finding of bacterial colonization of catheters together with chronic glomerulonephritis and immune-complex deposits in kidneys in clinically asymptomatic sheep underscores the need for close microbiologic monitoring of catheter implants and assessment of kidney function in animals instrumented for long-term vascular access. PMID:16884173

  14. Lutheran/basal cell adhesion molecule accelerates progression of crescentic glomerulonephritis in mice

    PubMed Central

    Huang, Jin; Filipe, Anne; Rahuel, Cécile; Bonnin, Philippe; Mesnard, Laurent; Guérin, Coralie; Wang, Yu; Le Van Kim, Caroline; Colin, Yves; Tharaux, Pierre-Louis

    2014-01-01

    Migration of circulating leukocytes from the vasculature into the surrounding tissue is an important component of the inflammatory response. Among the cell surface molecules identified as contributing to leukocyte extravasation is VCAM-1, expressed on activated vascular endothelium, which participates in all stages of leukocyte–endothelial interaction by binding to leukocyte surface expressed integrin VLA-4. However, not all VLA-4-mediated events can be linked to VCAM-1. A novel interaction between VLA-4 and endothelial Lutheran (Lu) blood group antigens and basal cell adhesion molecule (BCAM) proteins has been recently shown, suggesting that Lu/BCAM may have a role in leukocyte recruitments in inflamed tissues. Here, we assessed the participation of Lu/BCAM in the immunopathogenesis of crescentic glomerulonephritis. High expression of Lu/BCAM in glomeruli of mice with rapidly progressive glomerulonephritis suggests a potential role for the local expression of Lu/BCAM in nephritogenic recruitment of leukocytes. Genetic deficiency of Lu/BCAM attenuated glomerular accumulation of T cells and macrophages, crescent formation, and proteinuria, correlating with reduced fibrin and platelet deposition in glomeruli. Furthermore, we found a pro-adhesive interaction between human monocyte α4β1 integrin and Lu/BCAM proteins. Thus, Lu/BCAM may have a critical role in facilitating the accumulation of monocytes and macrophages, thereby exacerbating renal injury. PMID:24429403

  15. An immune-complex glomerulonephritis of Chinook salmon, Oncorhynchus tshawytscha (Walbaum).

    PubMed

    Lumsden, J S; Russell, S; Huber, P; Wybourne, B A; Ostland, V E; Minamikawa, M; Ferguson, H W

    2008-12-01

    Chinook salmon from New Zealand were shown to have a generalized membranous glomerulonephritis that was most severe in large fish. Marked thickening of the glomerular basement membrane was the most consistent lesion, with the presence of an electron-dense deposit beneath the capillary endothelium.Severely affected glomeruli also had expansion of the mesangium and loss of capillaries,synechiae of the visceral and parietal epithelium and mild fibrosis of Bowmans capsule. Chinook salmon from British Columbia, Canada with bacterial kidney disease caused by Renibacterium salmoninarum had similar histological lesions. They also had thickened glomerular basement membranes that were recognized by rabbit antiserum to rainbow trout immunoglobulin. This was true only when frozen sections of kidney were used and not formalin-fixed tissue. An attempt to experimentally produce a glomerulopathy in rainbow trout by repeated immunization with killed R. salmoninarum was not successful. Case records from the Fish Pathology Laboratory at the University of Guelph over a 10-year period revealed that a range of species were diagnosed with glomerulopathies similar to those seen in Chinook salmon. The majority of these cases were determined to have chronic inflammatory disease. This report has identified the presence of immunoglobulin within thickened basement membranes of Chinook salmon with glomerulonephritis and supports the existence of type III hypersensitivity in fish. PMID:18752546

  16. Long-term Variation of AGNs

    NASA Astrophysics Data System (ADS)

    Fan, J. H.; Xie, G. Z.; Adam, G.; Copin, Y.; Lin, R. G.; Bai, J. M.; Quin, Y. P.

    In this paper we will present the long-term variation in the optical and the infrared bands for some selected AGNs. 1. Some new optical data observed by us have been presented for BL Lacertae (1995-1996) and OJ 287 (1994-1995), and new infrared data are presented for OJ 287 (Nov=2E 1995), which corresponds to the second optical peak (Sillanpaa et al. 1996; Takalo et al. 1996) and during last outburst. 2. For objects with long term observations, the Jurkevich's method has been used to analyses the long-term variation period. It is interesting that the reported periods of AGNs are of the similar value of about 10 years: 3C 345 11.4 years (Webb et al. 1988), 3C 120 15 years (Belokon et al. 1987; Hagen-Thorn et al. 1997), ON 231 13.6 years (Liu et al. 1995), OJ 287 12 years (Sillanpaa et al. 1988; Kidger et al. 1992), PKS 0735+178 14 years (Fan et al. 1997), NGC 4151 15 years (Fan et al. 1998a), BL Lacertae 14.0 years (Fan et al. 1998b). Is the mechanism for the long-term variation the same for different AGNs? 3. The DCF method has been adopted to analysis the variation correlation in the optical and infrared bands for BL Lac object OJ 287, the results show that these two bands are strongly correlated, which suggest that the emission mechanism in the two bands is the same. 4. For the optical and infrared bands, the maximum variations are correlated.

  17. Optical variability of the Kepler AGN

    NASA Astrophysics Data System (ADS)

    Edelson, Rick

    2014-01-01

    Kepler has opened a new era for the study of AGN optical variability, producing light curves with ~0.1% errors (for a ~15th magnitude source), 30 min sampling, >90% duty cycle and durations of years. Thanks to an intensive identification campaign, the number of Seyfert 1s/quasars monitored by Kepler rose from just one (Zw 229-15) in the first year to 37 by the time of May 2013 reaction wheel failure. We measured the optical power spectral density (PSD) functions of these Kepler AGN finding that that on timescales of ~6 hr to 1 month, the PSDs are typically well-fitted with a slop of ~-3, steeper than seen in the X-rays. In a few sources there is also evidence for a flattening at the longest timescales. We also find a broad correlation between rms variability and flux level. These results broadly support the model in which the optical fluctuations are due to vicious instabilities in the accretion disk. I will also present the light curve for W2R1926+42, the only rapidly variable BL Lac object known to be monitored by Kepler. With data covering over a year and sampling rates of 1-30 min, this may be the information-richest AGN light curve ever gathered at any wavelength. The PSD appears to bend from a slope of -2.6 to -1.2 on a ~7 hr timescale, but fits are formally unacceptable. These data indicate that the phenomenon of blazar "microvariability" (sporadic variations on timescales shorter than the ~12 hour window available from the ground) actually results from a combination of rapid, powerful variability interspersed with longer, relatively quiescent periods.

  18. Warm Absorber Diagnostics of AGN Dynamics

    NASA Astrophysics Data System (ADS)

    Kallman, Timothy

    Warm absorbers and related phenomena are observable manifestations of outflows or winds from active galactic nuclei (AGN) that have great potential value. Understanding AGN outflows is important for explaining the mass budgets of the central accreting black hole, and also for understanding feedback and the apparent co-evolution of black holes and their host galaxies. In the X-ray band warm absorbers are observed as photoelectric absorption and resonance line scattering features in the 0.5-10 keV energy band; the UV band also shows resonance line absorption. Warm absorbers are common in low luminosity AGN and they have been extensively studied observationally. They may play an important role in AGN feedback, regulating the net accretion onto the black hole and providing mechanical energy to the surroundings. However, fundamental properties of the warm absorbers are not known: What is the mechanism which drives the outflow?; what is the gas density in the flow and the geometrical distribution of the outflow?; what is the explanation for the apparent relation between warm absorbers and the surprising quasi-relativistic 'ultrafast outflows' (UFOs)? We propose a focused set of model calculations that are aimed at synthesizing observable properties of warm absorber flows and associated quantities. These will be used to explore various scenarios for warm absorber dynamics in order to answer the questions in the previous paragraph. The guiding principle will be to examine as wide a range as possible of warm absorber driving mechanisms, geometry and other properties, but with as careful consideration as possible to physical consistency. We will build on our previous work, which was a systematic campaign for testing important class of scenarios for driving the outflows. We have developed a set of tools that are unique and well suited for dynamical calculations including radiation in this context. We also have state-of-the-art tools for generating synthetic spectra, which are

  19. The Starburst-AGN Connection under the Multiwavelength Limelight

    NASA Astrophysics Data System (ADS)

    Guainazzi, Matteo

    2011-11-01

    Since the discovery of a tight relation between supermassive black hole masses, the bulge luminosity, and the stellar velocity dispersion in the local universe galaxies, mounting experimental evidence has been collected pointing to a connection between nuclear activity and star formation over a wide range of redshifts. Although a growing number of galaxies from different samples exhibit simultaneous starburst and AGN phenomenology, it is still a matter of debate whether this is the smoking gun of a causal relation between them, and, if so, with which trend. Basic issues in modern astrophysics, such as the evolution of galaxies and supermassive black holes, AGN feeding and feedback to the interstellar and intergalactic medium, as well as the role played by the environment on the star formation history are related to this "Starburst-AGN Connection". This Workshop aims at gathering observational and theoretical astronomers so as to answer the following questions: * The "Starburst-AGN Connection": A causal relation? * "Starburst-AGN Connection" at low and high redshift: any evidence for evolution? * Is there a connection between AGN obscuration and star formation? * In which way are the star formation and AGN phenomena affected by the environment? * Do stars contribute to AGN fueling? Multiwavelength observations in the last decade have given a paramount contribution to improve our understanding in this field. The Workshop will build on this panoptic view, and aims at contributing to the scientific case of future ground-based and space large observatories.

  20. Propiedades de los AGNs oscurecidos y no oscurecidos

    NASA Astrophysics Data System (ADS)

    Taormina, M.; Bornancini, C.

    In this work we analyze the properties of obscured and unobscured AGNs selected from the "Multiwavelength Survey by Yale-Chile" (MUSYC). The sample of AGNs was selected base on their mid-infrared colors ([3.6], [4.5], [5.8] y [8.0] μm), from images obtained with the Spitzer Space Telescope. We select obscured and unobscured AGN samples using a simple criterion based on the observed optical to mid-IR color with limits R - [4.5] = 3.04 (AB system) and with redshifts in the range 1 < z < 3. Obscured AGNs are intrinsically optically faint in the R band, suggesting that luminous IR- selected AGNs have significant dust extinction. FULL TEXT IN SPANISH

  1. Uncovering AGN Fueling and Feedback in Dwarf Galaxies

    NASA Astrophysics Data System (ADS)

    Mushotzky, Richard

    2014-09-01

    While massive black holes (BHs) are ubiquitous in massive galaxies, their presence in dwarf galaxies is less certain. This constitutes a major gap in our understanding of BH-galaxy co-evolution. Identifying low-mass BHs in local dwarfs could also constrain BH seed formation at high z. Active BHs in dwarfs can reveal BH fueling and feedback in a vastly different regime than the well-studied AGN in massive hosts. Most AGN feedback models focus on the latter, as star formation is thought to suffice to drive feedback in dwarfs. However, AGN are increasingly found in dwarfs, where their effect on hosts may be most dramatic. We propose an unprecedented program to detect and characterize AGN fueling and feedback in the low-mass regime, using a unique sample of Swift-BAT AGN in dwarf

  2. Anchoring the AGN X-ray Luminosity Function

    NASA Astrophysics Data System (ADS)

    Salzer, John

    2003-09-01

    Knowledge of the AGN LF over a range of luminosities and redshifts is crucial to understanding the accretion history of supermassive blackholes. Much of the CXRB has been resolved and spectroscopic follow-up has revealed a mixed bag of object types at moderate to high redshifts. For the deep Chandra survey results to be useful in studying the evolution of the XLF, a representative sample of local AGNs of various types with known X-ray luminosities is needed. The new KPNO International Spectroscopic Survey (KISS) provides the best available sample of H-alpha selected Type 1 and 2 AGNs to serve as the baseline for XLF evolution studies. We propose to observe a volume-limited sample of 28 KISS AGNs to assess their X-ray emission characteristics and establish the local AGN XLF.

  3. Genetic factors influence level of proteinuria in cationic antigen-induced immune complex glomerulonephritis in the rat.

    PubMed Central

    Kato, A; Thaiss, F; Oite, T; Günther, E; Batsford, S; Vogt, A

    1985-01-01

    The influence of genetic factors on the susceptibility of the rat to cationic antigen-induced in situ immune complex glomerulonephritis was investigated. The levels of proteinuria developing in 11 inbred strains of rats differing in MHC and in genetic background varied markedly. Susceptibility was not MHC associated but resided in the genetic background. PMID:3159528

  4. α-1-Antitrypsin detected by MALDI imaging in the study of glomerulonephritis: Its relevance in chronic kidney disease progression.

    PubMed

    Smith, Andrew; L'Imperio, Vincenzo; De Sio, Gabriele; Ferrario, Franco; Scalia, Carla; Dell'Antonio, Giacomo; Pieruzzi, Federico; Pontillo, Claudia; Filip, Szymon; Markoska, Katerina; Granata, Antonio; Spasovski, Goce; Jankowski, Joachim; Capasso, Giovambattista; Pagni, Fabio; Magni, Fulvio

    2016-06-01

    Idiopathic glomerulonephritis (GN), such as membranous glomerulonephritis, focal segmental glomerulosclerosis (FSGS), and IgA nephropathy (IgAN), represent the most frequent primary glomerular kidney diseases (GKDs) worldwide. Although the renal biopsy currently remains the gold standard for the routine diagnosis of idiopathic GN, the invasiveness and diagnostic difficulty related with this procedure highlight the strong need for new diagnostic and prognostic biomarkers to be translated into less invasive diagnostic tools. MALDI-MS imaging MALDI-MSI was applied to fresh-frozen bioptic renal tissue from patients with a histological diagnosis of FSGS (n = 6), IgAN, (n = 6) and membranous glomerulonephritis (n = 7), and from controls (n = 4) in order to detect specific molecular signatures of primary glomerulonephritis. MALDI-MSI was able to generate molecular signatures capable to distinguish between normal kidney and pathological GN, with specific signals (m/z 4025, 4048, and 4963) representing potential indicators of chronic kidney disease development. Moreover, specific disease-related signatures (m/z 4025 and 4048 for FSGS, m/z 4963 and 5072 for IgAN) were detected. Of these signals, m/z 4048 was identified as α-1-antitrypsin and was shown to be localized to the podocytes within sclerotic glomeruli by immunohistochemistry. α-1-Antitrypsin could be one of the markers of podocyte stress that is correlated with the development of FSGS due to both an excessive loss and a hypertrophy of podocytes. PMID:26749278

  5. The PEP survey: infrared properties of radio-selected AGN

    NASA Astrophysics Data System (ADS)

    Magliocchetti, M.; Lutz, D.; Rosario, D.; Berta, S.; Le Floc'h, E.; Magnelli, B.; Pozzi, F.; Riguccini, L.; Santini, P.

    2014-07-01

    By exploiting the VLA-COSMOS and the Herschel-PEP surveys, we investigate the far-infrared (FIR) properties of radio-selected AGN. To this purpose, from VLA-COSMOS we considered the 1537, F1.4 GHz ≥ 0.06 mJy sources with a reliable redshift estimate, and sub-divided them into star-forming galaxies and AGN solely on the basis of their radio luminosity. The AGN sample is complete with respect to radio selection at all z ≲ 3.5. 832 radio sources have a counterpart in the PACS Evolutionary Probe catalogue. 175 are AGN. Their redshift distribution closely resembles that of the total radio-selected AGN population, and exhibits two marked peaks at z ˜ 0.9 and 2.5. We find that the probability for a radio-selected AGN to be detected at FIR wavelengths is both a function of radio power and redshift, whereby powerful sources are more likely to be FIR emitters at earlier epochs. This is due to two distinct effects: (1) at all radio luminosities, FIR activity monotonically increases with look-back time and (2) radio activity of AGN origin is increasingly less effective at inhibiting FIR emission. Radio-selected AGN with FIR emission are preferentially located in galaxies which are smaller than those hosting FIR-inactive sources. Furthermore, at all z ≲ 2, there seems to be a preferential (stellar) mass scale M* ˜ [1010-1011] M⊙ which maximizes the chances for FIR emission. We find such FIR (and mid-infrared) emission to be due to processes indistinguishable from those which power star-forming galaxies. It follows that radio emission in at least 35 per cent of the entire AGN population is the sum of two contributions: AGN accretion and star-forming processes within the host galaxy.

  6. A UV to mid-IR study of AGN selection

    SciTech Connect

    Chung, Sun Mi; Kochanek, Christopher S.; Assef, Roberto; Brown, Michael J. I.; Stern, Daniel; Jannuzi, Buell T.; Gonzalez, Anthony H.; Hickox, Ryan C.; Moustakas, John

    2014-07-20

    We classify the spectral energy distributions (SEDs) of 431,038 sources in the 9 deg{sup 2} Boötes field of the NOAO Deep Wide-Field Survey (NDWFS). There are up to 17 bands of data available per source, including ultraviolet (GALEX), optical (NDWFS), near-IR (NEWFIRM), and mid-infrared (IRAC and MIPS) data, as well as spectroscopic redshifts for ∼20,000 objects, primarily from the AGN and Galaxy Evolution Survey. We fit galaxy, active galactic nucleus (AGN), stellar, and brown dwarf templates to the observed SEDs, which yield spectral classes for the Galactic sources and photometric redshifts and galaxy/AGN luminosities for the extragalactic sources. The photometric redshift precision of the galaxy and AGN samples are σ/(1 + z) = 0.040 and σ/(1 + z) = 0.169, respectively, with the worst 5% outliers excluded. On the basis of the χ{sub ν}{sup 2} of the SED fit for each SED model, we are able to distinguish between Galactic and extragalactic sources for sources brighter than I = 23.5 mag. We compare the SED fits for a galaxy-only model and a galaxy-AGN model. Using known X-ray and spectroscopic AGN samples, we confirm that SED fitting can be successfully used as a method to identify large populations of AGNs, including spatially resolved AGNs with significant contributions from the host galaxy and objects with the emission line ratios of 'composite' spectra. We also use our results to compare with the X-ray, mid-IR, optical color, and emission line ratio selection techniques. For an F-ratio threshold of F > 10, we find 16,266 AGN candidates brighter than I = 23.5 mag and a surface density of ∼1900 AGN deg{sup –2}.

  7. Does the obscured AGN fraction really depend on luminosity?

    NASA Astrophysics Data System (ADS)

    Sazonov, S.; Churazov, E.; Krivonos, R.

    2015-12-01

    We use a sample of 151 local non-blazar active galactic nuclei (AGN) selected from the INTEGRAL all-sky hard X-ray survey to investigate if the observed declining trend of the fraction of obscured (i.e. showing X-ray absorption) AGN with increasing luminosity is mostly an intrinsic or selection effect. Using a torus-obscuration model, we demonstrate that in addition to negative bias, due to absorption in the torus, in finding obscured AGN in hard X-ray flux-limited surveys, there is also positive bias in finding unobscured AGN, due to Compton reflection in the torus. These biases can be even stronger taking into account plausible intrinsic collimation of hard X-ray emission along the axis of the obscuring torus. Given the AGN luminosity function, which steepens at high luminosities, these observational biases lead to a decreasing observed fraction of obscured AGN with increasing luminosity even if this fraction has no intrinsic luminosity dependence. We find that if the central hard X-ray source in AGN is isotropic, the intrinsic (i.e. corrected for biases) obscured AGN fraction still shows a declining trend with luminosity, although the intrinsic obscured fraction is significantly larger than the observed one: the actual fraction is larger than ˜85 per cent at L ≲ 1042.5 erg s-1 (17-60 keV), and decreases to ≲60 per cent at L ≳ 1044 erg s-1. In terms of the half-opening angle θ of an obscuring torus, this implies that θ ≲ 30° in lower luminosity AGN, and θ ≳ 45° in higher luminosity ones. If, however, the emission from the central supermassive black hole is collimated as dL/dΩ ∝ cos α, the intrinsic dependence of the obscured AGN fraction is consistent with a luminosity-independent torus half-opening angle θ ˜ 30°.

  8. Extremely efficient Zevatron in rotating AGN magnetospheres

    NASA Astrophysics Data System (ADS)

    Osmanov, Z.; Mahajan, S.; Machabeli, G.; Chkheidze, N.

    2014-12-01

    A novel model of particle acceleration in the magnetospheres of rotating active galactic nuclei (AGN) is constructed. The particle energies may be boosted up to 1021 eV in a two-step mechanism: in the first stage, the Langmuir waves are centrifugally excited and amplified by means of a parametric process that efficiently pumps rotational energy to excite electrostatic fields. In the second stage, the electrostatic energy is transferred to particle kinetic energy via Landau damping made possible by rapid `Langmuir collapse'. The time-scale for parametric pumping of Langmuir waves turns out to be small compared to the kinematic time-scale, indicating high efficiency of the first process. The second process of `Langmuir collapse' - the creation of caverns or low-density regions - also happens rapidly for the characteristic parameters of the AGN magnetosphere. The Langmuir collapse creates appropriate conditions for transferring electric energy to boost up already high particle energies to much higher values. It is further shown that various energy loss mechanism are relatively weak, and do not impose any significant constraints on maximum achievable energies.

  9. Extending the Fermi - Swift Joint AGN Sample

    NASA Astrophysics Data System (ADS)

    Shrader, Chris R.; Macomb, D. J.

    2014-01-01

    The Swift BAT and the Fermi LAT each provide excellent sky coverage and have led to impressive compilations of extragalactic source catalogs. For the most part they sample separate AGN subpopulations - Swift the lower-luminosity and relatively nearby Seyfert galaxies while the Fermi sample is dominated by blazars and does not include any radio-quiet objects. The overlap between these samples is among the radio-loud subset of the Swift sample as has been discussed elsewhere in the literature. The observable properties at these two bands - flux and spectral indices - are not expected to be well correlated as they sample different portions of the synchrotron self-Compton (SSC) spectral energy distribution. In this contribution we consider an extension of the high-latitude Swift sample by relaxing the significance cut to less than 5 standard deviations and consider the overlap of that subsample with the Fermi AGN catalog. While such a threshold is generally inadvisable as it introduces the strong possibility of spurious detections, the objects of the overlapping sample which are detected at high significance in Fermi can be considered as reasonably high-confidence Swift detections. For example, there are 190 Swift sub-5-sigma Swift sources that have significance >2-sigma with Fermi counterparts, whereas we predict only ~5 due to statistical fluctuation. We also investigate any coincident INTEGRAL/IBIS observations to further bolster or diminish candidate Swift detections. We present our correlation analyses and offer interpretation in the context of the blazar sequence.

  10. IgA-dominant post-infectious glomerulonephritis; making another case in support of renal biopsy in type 2 diabetic nephropathy

    PubMed Central

    Nayer, Ali; Davda, Gargi; Pai, Rima; Ortega, Luis M.

    2016-01-01

    Background: Approximately one-third of individuals with type 2 diabetes mellitus will eventually develop diabetic nephropathy (DN). Impaired renal function in type 2 diabetics may also be secondary to non-diabetic renal disease (NDRD). NDRD in type 2 diabetics may occur alone in the absence of DN or may be superimposed on DN. Renal biopsy maybe indicated to establish the correct diagnosis and to ascertain the severity of glomerular and tubulointerstitial pathology. Case: We report a patient with type 2 diabetes mellitus and chronic renal insufficiency who developed worsening of renal function in the setting of staphylococcal infection and antibiotic use. Conclusion: Renal biopsy revealed IgA-dominant post-infectious glomerulonephritis and acute interstitial nephritis superimposed on diabetic glomerulosclerosis. Accumulating evidence indicates that, NDRD accounts for impaired renal function in a significant number of patients with type 2 diabetes mellitus. The presence of clinical, biochemical, and radiological features that suggest NDRD should prompt pathological evaluation of the kidney. PMID:27069968

  11. Independent associations of urine neutrophil gelatinase–associated lipocalin and serum uric acid with interstitial fibrosis and tubular atrophy in primary glomerulonephritis

    PubMed Central

    Lertrit, Amornpan; Worawichawong, Suchin; Vanavanan, Somlak; Chittamma, Anchalee; Muntham, Dittapol; Radinahamed, Piyanuch; Nampoon, Aumporn; Kitiyakara, Chagriya

    2016-01-01

    The degree of interstitial fibrosis and tubular atrophy (IFTA) is one of the strongest prognostic factors in glomerulonephritis (GN). In experimental models, high serum uric acid (UA) could contribute to IFTA through direct effects on the renal tubules, but the significance of this process has not been evaluated in patients. Urine neutrophil gelatinase–associated lipocalin (NGAL) is produced by renal tubules following acute or chronic damage. We investigated the relationship between UA and NGAL excretion in primary GN and tested whether these biomarkers are independently associated with IFTA. Urine and blood were collected from patients on the day of kidney biopsy. IFTA was assessed semi-quantitatively. Fifty-one patients with primary GN were enrolled. NGAL/creatinine correlated significantly with proteinuria but not with glomerular filtration rate (GFR). By contrast, UA correlated with GFR but not with proteinuria. NGAL/creatinine did not correlate with UA. Both NGAL/creatinine and UA increased with the severity of IFTA. By multivariate analysis, GFR, NGAL/creatinine, and UA were independently associated with moderate-to-severe IFTA. Combining UA and NGAL/creatinine with classical predictors (proteinuria and GFR) tended to improve discrimination for moderate-to-severe IFTA. Findings that UA was unrelated to urinary NGAL excretion suggest that the two biomarkers reflect different pathways related to the development of IFTA in primary GN. Both NGAL/creatinine and UA were independently associated with moderate-to-severe IFTA. PMID:27143950

  12. Membranoproliferative glomerulonephritis

    MedlinePlus

    ... glomeruli. The glomeruli of the kidney help filter wastes and fluids from the blood to form urine. ... the glomerular basement membrane. This membrane helps filter wastes and extra fluids from the blood. Damage to ...

  13. Structure Function Analysis of AGN Variability using Kepler

    NASA Astrophysics Data System (ADS)

    Kasliwal, Vishal P.; Vogeley, Michael S.; Richards, Gordon T.

    2014-06-01

    We study the variability properties of AGN light-curves observed by the Kepler satellite. AGN optical fluxes are known to exhibit stochastic variations on time-scales of hours, days, months and years. Previous efforts to characterize the stochastic nature of this variability have been hampered by the lack of high-precision space-based measurements of AGN fluxes with regular cadence. Kepler provides light-curves with a S/N ratio of 10-5 for 87 AGN observed over a period of ~ 3 years with a cadence of once every 30 minutes allowing for a detailed examination of the variability process. We probe AGN variability using the Structure Functions of the light-curves of the Kepler AGN. Monte-Carlo simulations of the structure function are used to fit the observed light-curve to models for the Power Spectral Density. We test various models for the form of the PSD including the damped random walk and the powered exponential models. We show that on the shorter time-scales probed by Kepler data, the damped random walk model fails to adequately characterize AGN variability. We find that the PSD may be better modelled by combination of a steep power law of the form 1/f3 on shorter time-scales, and a more shallow power law of the form 1/f2 on the longer time-scales traditionally probed by ground-based variability studies.

  14. Star Formation Quenching and Identifying AGN in Galaxies

    NASA Astrophysics Data System (ADS)

    Mendez, Alexander; Coil, A. L.; Lotz, J. M.; Aird, J.; Diamond-Stanic, A. M.; Moustakas, J.; Salim, S.; Simard, L.; Blanton, M. R.; Eisenstein, D.; Wong, K. C.; Cool, R. J.; Zhu, G.; PRIMUS; AEGIS

    2014-01-01

    I will discuss two observational projects related to galaxy and active galactic nuclei (AGN) evolution at z < 1. First I will present a statistical study of the morphologies of galaxies in which star formation is being shut down or quenched; this has implications for how red, elliptical galaxies are formed. I will discuss the physical processes behind star formation quenching from the morphological transformations that galaxies undergo during this process. Then I will focus on multi-wavelength AGN selection methods and tie together disparate results in the literature. Several IR-AGN selection methods have been developed using Spitzer/IRAC data in order to supplement traditional X-ray AGN selection; I will characterize the uniqueness and complementarity of these methods as a function of both IR and X-ray depth. I will use data from the PRIsm MUlti-object Survey (PRIMUS) to compare the efficiency of IR and X-ray AGN selection and discuss the properties of the AGN and host galaxy populations of each. Finally, I will briefly mention ongoing work to compare the clustering of observed IR and X-ray AGN samples relative to stellar mass-matched galaxy samples.

  15. Spectral decomposition of broad-line agns and host galaxies

    SciTech Connect

    Vanden Berk, Daniel E.; Shen, Jiajian; Yip, Ching-Wa; Schneider, Donald P.; Connolly, Andrew J.; Burton, Ross E.; Jester, Sebastian; Hall, Patrick B.; Szalay, Alex S.; Brinkmann, John; /Apache Point Observ.

    2005-09-01

    Using an eigenspectrum decomposition technique, we separate the host galaxy from the broad line active galactic nucleus (AGN) in a set of 4666 spectra from the Sloan Digital Sky Survey (SDSS), from redshifts near zero up to about 0.75. The decomposition technique uses separate sets of galaxy and quasar eigenspectra to efficiently and reliably separate the AGN and host spectroscopic components. The technique accurately reproduces the host galaxy spectrum, its contributing fraction, and its classification. We show how the accuracy of the decomposition depends upon S/N, host galaxy fraction, and the galaxy class. Based on the eigencoefficients, the sample of SDSS broad-line AGN host galaxies spans a wide range of spectral types, but the distribution differs significantly from inactive galaxies. In particular, post-starburst activity appears to be much more common among AGN host galaxies. The luminosities of the hosts are much higher than expected for normal early-type galaxies, and their colors become increasingly bluer than early-type galaxies with increasing host luminosity. Most of the AGNs with detected hosts are emitting at between 1% and 10% of their estimated Eddington luminosities, but the sensitivity of the technique usually does not extend to the Eddington limit. There are mild correlations among the AGN and host galaxy eigencoefficients, possibly indicating a link between recent star formation and the onset of AGN activity. The catalog of spectral reconstruction parameters is available as an electronic table.

  16. Compton Thick AGN in the XMM-COSMOS field

    NASA Astrophysics Data System (ADS)

    Lanzuisi, G.; Perna, M.; Delvecchio, I.; Berta, S.; Brusa, M.; Gruppioni, C.; Comastri, A.

    2016-06-01

    I will present results we published in two recent papers (Lanzuisi et al. 2015, A&A 573A 137, Lanzuisi et al. 2015, A&A 578A 120) on the properties of X-ray selected Compton Thick (CT, NH>10^{24} cm^{-2}) AGN, in the XMM-COSMOS survey. We exploited the rich multi-wavelength dataset available in this field, to show that CT AGN tend to harbor smaller, rapidly growing SMBH with respect to unobscured AGN, and have a higher chance of being hosted by star-forming, merging and post-merger systems. We also demonstrated the detectability of even more heavily obscured AGN (NH>10^{25} cm^{-2}), thanks to a truly multi-wavelength approach in the same field, and to the unrivaled XMM sensitivity. The extreme source detected in this way shows strong evidences of ongoing powerful AGN feedback, detected as blue-shifted wings of high ionization optical emission lines such as [NeV] and [FeVII], as well as of the [OIII] emission line. The results obtained from these works point toward a scenario in which highly obscured AGN occupy a peculiar place in the galaxy-AGN co-evolution process, in which both the host and the SMBH rapidly evolve toward the local relations.

  17. Cadence Requirements for AGN Accretion Studies with LSST

    NASA Astrophysics Data System (ADS)

    Moreno, Jackeline; Vogeley, Michael S.; Richards, Gordon T.; Kasliwal, Vishal P.

    2016-01-01

    We test various samplings of mock AGN lightcurves to determine minimum cadence requirements for future technologies like the Large Synoptic Survey Telescope (LSST). AGN lightcurves exhibit stochastic behavior, with variability seen in ground-based optical surveys on timescales from days to years. Significant variability structure on timescales up to a few days was revealed by the high time resolution (~30 minutes) of Kepler Satellite. Now it is apparent that under-sampling by ground based instruments may be leaving out a big chunk of the AGN accretion picture. To probe Kepler AGN, recent studies have investigated the suitability of sophisticated models like CARMA processes to better understand dominant mechanisms driving observed variability across these timescales. By testing models against AGN photometry, we gain insights about accretion physics, intrinsic differences between AGN sub-types, and physical scales pertaining to orbits or casually connected matter flows. We investigate cadence, time window, and regularity requirements that accurately recover parameters of our model lightcurves constructed with a CARMA process and observations such that ground based telescopes can optimally collect data for AGN science.

  18. Studying AGN Feedback with Galactic Outflows in Luminous Obscured Quasar

    NASA Astrophysics Data System (ADS)

    Sun, Ai-Lei

    2016-01-01

    Feedback from Active galactic nuclei (AGN) has been proposed as an important quenching mechanism to suppress star formation in massive galaxies. We investigate the most direct form of AGN feedback - galactic outflows - in the most luminous obscured AGN (L>10^45 erg/s) from the SDSS sample in the nearby universe (z<0.2). Using ALMA and Magellan observations to target molecular and ionized outflows, we find that luminous AGN can impact the dynamics and phase of the galactic medium, and confirm the complex multi-phase and multi-scaled nature of the feedback phenomenon. In particular, we found that most of these luminous AGN hosts ionized outflows. The outflow size, velocity, and energetics correlate with the AGN luminosity, and can be very extended (r > 10 kpc) and fast (v > 1000 km/s) for the most luminous ones. I end with presenting a new technique to find extended ionized outflows using broadband imaging surveys, and to characterize their occurrence rate, morphology, size distribution, and their dependence on the AGN luminosity. This technique will open a new window for feedback studies in the era of large-scale optical imaging surveys, e.g., HSC and then LSST.

  19. Mid-infrared diagnostics to distinguish AGNs from starbursts

    NASA Astrophysics Data System (ADS)

    Laurent, O.; Mirabel, I. F.; Charmandaris, V.; Gallais, P.; Madden, S. C.; Sauvage, M.; Vigroux, L.; Cesarsky, C.

    2000-07-01

    We present new mid-infrared (MIR) diagnostics to distinguish emission of active galactic nuclei (AGN) from that originating in starburst regions. Our method uses empirical spectroscopic criteria based on the fact that MIR emission from star forming or active galaxies arises mostly from HII regions, photo-dissociation regions (PDRs) and AGNs. The analysis of the strength of the 6.2 mu m Unidentified Infrared Band (UIB) and the MIR continuum shows that UIBs are very faint or absent in regions harboring the intense and hard radiation fields of AGNs and pure HII regions, where the UIB carriers could be destroyed. The MIR signature of AGNs is the presence of an important continuum in the 3-10 mu m band which originates from very hot dust heated by the intense AGN radiation field. Using these two distinct spectral properties found in our MIR templates, we build diagnostic diagrams which provide quantitative estimates of the AGN, PDR and HII region contribution in a given MIR spectrum. This new MIR classification can be used to reveal the presence of AGNs highly obscured by large columns of dust. Based on observations made with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with the participation of ISAS and NASA.

  20. Compton Thick AGN in the XMM-COSMOS field

    NASA Astrophysics Data System (ADS)

    Lanzuisi, G.; Perna, M.; Delvecchio, I.; Berta, S.; Brusa, M.; Gruppioni, C.; Comastri, A.

    2016-06-01

    I will present results we published in two recent papers (Lanzuisi et al. 2015, A&A 573A 137, Lanzuisi et al. 2015, A≈A 578A 120) on the properties of X-ray selected Compton Thick (CT, NH>10^{24} cm^{-2}) AGN, in the XMM-COSMOS survey. We exploited the rich multi-wavelength dataset available in this field, to show that CT AGN tend to harbor smaller, rapidly growing SMBH with respect to unobscured AGN, and have a higher chance of being hosted by star-forming, merging and post-merger systems. We also demonstrated the detectability of even more heavily obscured AGN (NH>10^{25} cm^{-2}), thanks to a truly multi-wavelength approach in the same field, and to the unrivaled XMM sensitivity. The extreme source detected in this way shows strong evidences of ongoing powerful AGN feedback, detected as blue-shifted wings of high ionization optical emission lines such as [NeV] and [FeVII], as well as of the [OIII] emission line. The results obtained from these works point toward a scenario in which highly obscured AGN occupy a peculiar place in the galaxy-AGN co-evolution process, in which both the host and the SMBH rapidly evolve toward the local relations.

  1. Absorption-line measurements of AGN outflows

    NASA Astrophysics Data System (ADS)

    Fields, Dale L.

    Investigations into the elemental abundances in two nearby active galaxies, the narrow-line Seyfert 1 Markarian 1044 and the Seyfert 1 Markarian 279, are reported. Spectra from three space-based observatories HST, FUSE, and CHANDRA, are used to measure absorption lines in material outflowing from the nucleus. I make multi-wavelength comparisons to better convert the ionic column densities into elemental column densities which can then be used to determine abundances (metallicities). Narrow-line Seyfert 1 galaxies are known to have extreme values of a number of properties compared to active galactic nuclei (AGNs) as a class. In particular, emission-line studies have suggested that NLS1s are unusually metal-rich compared to broad-line AGNs of comparable luminosity. To test these suggestions I perform absorption-line studies on the NLS1 Markarian 1044, a nearby and bright AGN. I use lines of H I, C IV, N V, and O VI to properly make the photoionization correction through the software Cloudy and determine abundances of Carbon, Nitrogen and Oxygen. I find two results. The first is that Markarian 1044 has a bulk metallicity greater than five times solar. The second is that the N/C ratio in Markarian 1044 is consistent with a solar mixture. This is in direct contradiction of extrapolations from local H II regions which state N/ C should scale with bulk metallicity. This implies a different enrichment history in Markarian 1044 than in the Galactic disk. I also report discovery of three new low-redshift Lya forest lines with log N HI >= 12:77 in the spectrum of Markarian 1044. This number is consistent with the 2.6 expected Lya forest lines in the path length to Markarian 1044. I also investigate the CHANDRA X-ray spectrum of Markarian 279, a broad-line Seyfert 1. I use a new code, PHASE, to self-consistently model the entire absorption spectrum simultaneously. Using solely the X-ray spectrum I am able to determine the physical parameters of this absorber to a degree only

  2. The Swift AGN and Cluster Survey

    NASA Astrophysics Data System (ADS)

    Danae Griffin, Rhiannon; Dai, Xinyu; Kochanek, Christopher S.; Bregman, Joel N.; Nugent, Jenna

    2016-01-01

    The Swift active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125 deg^2 of Swift X-ray Telescope serendipitous fields with variable depths surrounding X-ray bursts to provide a medium depth (4 × 10^-15 erg cm^-2 s^-1) and area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. Here, we present the first two papers in a series of publications for SACS. In the first paper, we introduce our method and catalog of 22,563 point sources and 442 extended sources. We examine the number counts of the AGN and galaxy cluster populations. SACS provides excellent constraints on the AGN number counts at the bright end with negligible uncertainties due to cosmic variance, and these constraints are consistent with previous measurements. The depth and areal coverage of SACS is well suited for galaxy cluster surveys outside the local universe, reaching z ˜ 1 for massive clusters. In the second paper, we use Sloan Digital Sky Survey (SDSS) DR8 data to study the 203 extended SACS sources that are located within the SDSS footprint. We search for galaxy over-densities in 3-D space using SDSS galaxies and their photometric redshifts near the Swift galaxy cluster candidates. We find 103 Swift clusters with a > 3σ over-density. The remaining targets are potentially located at higher redshifts and require deeper optical follow-up observations for confirmations as galaxy clusters. We present a series of cluster properties including the redshift, BCG magnitude, BCG-to-X-ray center offset, optical richness, X-ray luminosity and red sequences. We compare the observed redshift distribution of the sample with a theoretical model, and find that our sample is complete for z ≤ 0.3 and 80% complete for z ≤ 0.4, consistent with the survey depth of SDSS. We also match our SDSS confirmed Swift clusters to existing cluster catalogs, and find 42, 2 and 1 matches in optical, X-ray and SZ catalogs, respectively, so the majority of these

  3. Supernovae and AGN Driven Galactic Outflows

    NASA Astrophysics Data System (ADS)

    Sharma, Mahavir; Nath, Biman B.

    2013-01-01

    We present analytical solutions for winds from galaxies with a Navarro-Frank-White (NFW) dark matter halo. We consider winds driven by energy and mass injection from multiple supernovae (SNe), as well as momentum injection due to radiation from a central black hole. We find that the wind dynamics depends on three velocity scales: (1) v_\\star ˜ (\\dot{E} / 2 \\dot{M})^{1/2} describes the effect of starburst activity, with \\dot{E} and \\dot{M} as energy and mass injection rate in a central region of radius R; (2) v • ~ (GM •/2R)1/2 for the effect of a central black hole of mass M • on gas at distance R; and (3) v_{s} =(GM_h / 2 {C}r_s)^{1/2}, which is closely related to the circular speed (vc ) for an NFW halo, where rs is the halo scale radius and {C} is a function of the halo concentration parameter. Our generalized formalism, in which we treat both energy and momentum injection from starbursts and radiation from the central active galactic nucleus (AGN), allows us to estimate the wind terminal speed to be (4v 2 sstarf + 6(Γ - 1)v • 2 - 4v 2 s )1/2, where Γ is the ratio of force due to radiation pressure to gravity of the central black hole. Our dynamical model also predicts the following: (1) winds from quiescent star-forming galaxies cannot escape from 1011.5 M ⊙ <= Mh <= 1012.5 M ⊙ galaxies; (2) circumgalactic gas at large distances from galaxies should be present for galaxies in this mass range; (3) for an escaping wind, the wind speed in low- to intermediate-mass galaxies is ~400-1000 km s-1, consistent with observed X-ray temperatures; and (4) winds from massive galaxies with AGNs at Eddington limit have speeds >~ 1000 km s-1. We also find that the ratio [2v 2 sstarf - (1 - Γ)v • 2]/v 2 c dictates the amount of gas lost through winds. Used in conjunction with an appropriate relation between M • and Mh and an appropriate opacity of dust grains in infrared (K band), this ratio has the attractive property of being minimum at a certain halo

  4. Radio AGN in the local universe: unification, triggering and evolution

    NASA Astrophysics Data System (ADS)

    Tadhunter, Clive

    2016-06-01

    Associated with one of the most important forms of active galactic nucleus (AGN) feedback, and showing a strong preference for giant elliptical host galaxies, radio AGN (L_{1.4 GHz} > 10^{24} W Hz^{-1}) are a key sub-class of the overall AGN population. Recently their study has benefitted dramatically from the availability of high-quality data covering the X-ray to far-IR wavelength range obtained with the current generation of ground- and space-based telescope facilities. Reflecting this progress, here I review our current state of understanding of the population of radio AGN at low and intermediate redshifts (z < 0.7), concentrating on their nuclear AGN and host galaxy properties, and covering three interlocking themes: the classification of radio AGN and its interpretation; the triggering and fuelling of the jet and AGN activity; and the evolution of the host galaxies. I show that much of the observed diversity in the AGN properties of radio AGN can be explained in terms of a combination of orientation/anisotropy, mass accretion rate, and variability effects. The detailed morphologies of the host galaxies are consistent with the triggering of strong-line radio galaxies (SLRG) in galaxy mergers. However, the star formation properties and cool ISM contents suggest that the triggering mergers are relatively minor in terms of their gas masses in most cases, and would not lead to major growth of the supermassive black holes and stellar bulges; therefore, apart from a minority (<20 %) that show evidence for higher star formation rates and more massive cool ISM reservoirs, the SLRG represent late-time re-triggering of activity in mature giant elliptical galaxies. In contrast, the host and environmental properties of weak-line radio galaxies (WLRG) with Fanaroff-Riley class I radio morphologies are consistent with more gradual fuelling of the activity via gas accretion at low rates onto the supermassive black holes.

  5. Disentangling AGN and Star Formation in Soft X-Rays

    NASA Technical Reports Server (NTRS)

    LaMassa, Stephanie M.; Heckman, T. M.; Ptak, A.

    2012-01-01

    We have explored the interplay of star formation and active galactic nucleus (AGN) activity in soft X-rays (0.5-2 keV) in two samples of Seyfert 2 galaxies (Sy2s). Using a combination of low-resolution CCD spectra from Chandra and XMM-Newton, we modeled the soft emission of 34 Sy2s using power-law and thermal models. For the 11 sources with high signal-to-noise Chandra imaging of the diffuse host galaxy emission, we estimate the luminosity due to star formation by removing the AGN, fitting the residual emission. The AGN and star formation contributions to the soft X-ray luminosity (i.e., L(sub x,AGN) and L(sub x,SF)) for the remaining 24 Sy2s were estimated from the power-law and thermal luminosities derived from spectral fitting. These luminosities were scaled based on a template derived from XSINGS analysis of normal star-forming galaxies. To account for errors in the luminosities derived from spectral fitting and the spread in the scaling factor, we estimated L(sub x,AGN) and L(sub x,SF))from Monte Carlo simulations. These simulated luminosities agree with L(sub x,AGN) and L(sub x,SF) derived from Chandra imaging analysis within a 3sigma confidence level. Using the infrared [Ne ii]12.8 micron and [O iv]26 micron lines as a proxy of star formation and AGN activity, respectively, we independently disentangle the contributions of these two processes to the total soft X-ray emission. This decomposition generally agrees with L(sub x,SF) and L(sub x,AGN) at the 3 sigma level. In the absence of resolvable nuclear emission, our decomposition method provides a reasonable estimate of emission due to star formation in galaxies hosting type 2 AGNs.

  6. DISENTANGLING AGN AND STAR FORMATION IN SOFT X-RAYS

    SciTech Connect

    LaMassa, Stephanie M.; Heckman, T. M.; Ptak, A.

    2012-10-20

    We have explored the interplay of star formation and active galactic nucleus (AGN) activity in soft X-rays (0.5-2 keV) in two samples of Seyfert 2 galaxies (Sy2s). Using a combination of low-resolution CCD spectra from Chandra and XMM-Newton, we modeled the soft emission of 34 Sy2s using power-law and thermal models. For the 11 sources with high signal-to-noise Chandra imaging of the diffuse host galaxy emission, we estimate the luminosity due to star formation by removing the AGN, fitting the residual emission. The AGN and star formation contributions to the soft X-ray luminosity (i.e., L{sub x,AGN} and L{sub x,SF}) for the remaining 24 Sy2s were estimated from the power-law and thermal luminosities derived from spectral fitting. These luminosities were scaled based on a template derived from XSINGS analysis of normal star-forming galaxies. To account for errors in the luminosities derived from spectral fitting and the spread in the scaling factor, we estimated L{sub x,AGN} and L{sub x,SF} from Monte Carlo simulations. These simulated luminosities agree with L{sub x,AGN} and L{sub x,SF} derived from Chandra imaging analysis within a 3{sigma} confidence level. Using the infrared [Ne II]12.8 {mu}m and [O IV]26 {mu}m lines as a proxy of star formation and AGN activity, respectively, we independently disentangle the contributions of these two processes to the total soft X-ray emission. This decomposition generally agrees with L{sub x,SF} and L{sub x,AGN} at the 3{sigma} level. In the absence of resolvable nuclear emission, our decomposition method provides a reasonable estimate of emission due to star formation in galaxies hosting type 2 AGNs.

  7. Phospholipase A2 Receptor-Positive Idiopathic Membranous Glomerulonephritis with Onset at 95 Years: Case Report

    PubMed Central

    Kubota, Keiichi; Hoshino, Junichi; Ueno, Toshiharu; Mise, Koki; Hazue, Ryo; Sekine, Akinari; Yabuuchi, Junko; Yamanouchi, Masayuki; Suwabe, Tatsuya; Kikuchi, Koichi; Sumida, Keiichi; Hayami, Noriko; Sawa, Naoki; Takaichi, Kenmei; Fujii, Takeshi; Ohashi, Kenichi; Akiyama, Shinichi; Maruyama, Shoichi; Ubara, Yoshifumi

    2016-01-01

    A 95-year-old woman was admitted to our hospital for evaluation of bilateral lower-limb edema persisting for 3 months. Serum creatinine was 1.55 mg/dl, and urinary protein excretion was 9.1 g/day. Renal biopsy revealed stage 1 membranous glomerulonephritis (MGN) with immunoglobulin G4-dominant staining. This patient did not have any underlying disease such as infection with hepatitis B or C virus or malignancy, and anti-phospholipase A2 receptor (PLA2R) antibody was detected in the serum. Accordingly, idiopathic MGN was diagnosed. Corticosteroid therapy was avoided, but hemodialysis was required to treat generalized edema. The patient is currently doing well. This is the oldest reported case of idiopathic MGN with positivity for anti-PLA2R antibody. PMID:27390744

  8. Clinicopathologic correlations in a series of 143 patients with IgA glomerulonephritis.

    PubMed

    Mustonen, J; Pasternack, A; Helin, H; Nikkilä, M

    1985-01-01

    In an unselected series of patients with IgA glomerulonephritis, old age, high blood pressure, and high urinary protein excretion at the time of renal biopsy were found to correlate with impaired renal function, whereas sex, estimated duration of the disease, or high serum IgA levels did not. The following clinical features were favorable prognostic signs: asymptomatic proteinuria, macroscopic hematuria, and isolated microscopic hematuria. The degree of diffuse mesangial alteration and the presence of segmental glomerular lesions correlated clearly with the subsequent clinical outcome. Vascular lesions, i.e. arteriosclerosis and renal vascular deposition of C3, were most often present in patients with severe glomerulopathy. The presence of electron-dense deposits in glomerular capillary walls was also an unfavorable prognostic finding. Renal biopsy findings of interstitial infiltrates of inflammatory cells and IgA distributed along glomerular capillary walls were usually associated with extrarenal manifestations of the disease. PMID:4014321

  9. An immunohistological study of feline glomerulonephritis using the peroxidase-antiperoxidase method.

    PubMed

    Arthur, J E; Lucke, V M; Newby, T J; Bourne, F J

    1984-07-01

    Twenty-two cases of feline glomerulonephritis were investigated for the presence of immune complexes within the glomerulus using the peroxidase-antiperoxidase (PAP) method. This method was used with formalin-fixed paraffin-wax embedded tissues which were pretreated with trypsin and with frozen sections of kidney tissue. Of a total of 25 kidney specimens examined (two cats had repeated biopsies) the composition of the deposits was 23/25 IgG, 17/25 C3, 11/25 IgM and 2/25 IgA. Serial studies of two cats showed a progression of the disease from initial nephrotic syndrome to chronic renal failure. With the more severe form of the disease there was a tendency for the deposition of complement and more than one class of immunoglobulin within the glomeruli. PMID:6382492

  10. Treatment of choroidal neovascularisation secondary to membranoproliferative glomerulonephritis type II with intravitreal ranibizumab

    PubMed Central

    McCullagh, Donal; Silvestri, Giuliana; Maxwell, Alexander P

    2014-01-01

    Membranoproliferative glomerulonephritis type II (MPGN II) is characterised by electron-dense deposits of complement components in the glomerular basement membrane and retinal pigment epithelium. Approximately, 10% of affected individuals develop serious ocular complications similar to age-related macular degeneration such as choroidal neovascularisation (CNV), which has been managed with photocoagulation or photodynamic therapy; however, these treatments can impact visual acuity. We report the case of a 42-year-old woman with MPGN II presenting with decreased visual acuity and paracentral scotoma in her left eye due to an extrafoveal choroidal neovascular membrane (growth of new vessels under the retina). The patient was successfully treated with intravitreal ranibizumab (Lucentis) with restoration of visual function. This case highlights the successful management of CNV secondary to MPGN II with the antivascular endothelial growth factor agent ranibizumab and emphasises the importance of early referral of patients with MPGN II who are reporting of visual ‘distortion’. PMID:24895384

  11. Reclassification of membranoproliferative glomerulonephritis: Identification of a new GN: C3GN

    PubMed Central

    Salvadori, Maurizio; Rosso, Giuseppina

    2016-01-01

    This review revises the reclassification of the membranoproliferative glomerulonephritis (MPGN) after the consensus conference that by 2015 reclassified all the glomerulonephritis basing on etiology and pathogenesis, instead of the histomorphological aspects. After reclassification, two types of MPGN are to date recognized: The immunocomplexes mediated MPGN and the complement mediated MPGN. The latter type is more extensively described in the review either because several of these entities are completely new or because the improved knowledge of the complement cascade allowed for new diagnostic and therapeutic approaches. Overall the complement mediated MPGN are related to acquired or genetic cause. The presence of circulating auto antibodies is the principal acquired cause. Genetic wide association studies and family studies allowed to recognize genetic mutations of different types as causes of the complement dysregulation. The complement cascade is a complex phenomenon and activating factors and regulating factors should be distinguished. Genetic mutations causing abnormalities either in activating or in regulating factors have been described. The diagnosis of the complement mediated MPGN requires a complete study of all these different complement factors. As a consequence, new therapeutic approaches are becoming available. Indeed, in addition to a nonspecific treatment and to the immunosuppression that has the aim to block the auto antibodies production, the specific inhibition of complement activation is relatively new and may act either blocking the C5 convertase or the C3 convertase. The drugs acting on C3 convertase are still in different phases of clinical development and might represent drugs for the future. Overall the authors consider that one of the principal problems in finding new types of drugs are both the rarity of the disease and the consequent poor interest in the marketing and the lack of large international cooperative studies. PMID:27458560

  12. Reclassification of membranoproliferative glomerulonephritis: Identification of a new GN: C3GN.

    PubMed

    Salvadori, Maurizio; Rosso, Giuseppina

    2016-07-01

    This review revises the reclassification of the membranoproliferative glomerulonephritis (MPGN) after the consensus conference that by 2015 reclassified all the glomerulonephritis basing on etiology and pathogenesis, instead of the histomorphological aspects. After reclassification, two types of MPGN are to date recognized: The immunocomplexes mediated MPGN and the complement mediated MPGN. The latter type is more extensively described in the review either because several of these entities are completely new or because the improved knowledge of the complement cascade allowed for new diagnostic and therapeutic approaches. Overall the complement mediated MPGN are related to acquired or genetic cause. The presence of circulating auto antibodies is the principal acquired cause. Genetic wide association studies and family studies allowed to recognize genetic mutations of different types as causes of the complement dysregulation. The complement cascade is a complex phenomenon and activating factors and regulating factors should be distinguished. Genetic mutations causing abnormalities either in activating or in regulating factors have been described. The diagnosis of the complement mediated MPGN requires a complete study of all these different complement factors. As a consequence, new therapeutic approaches are becoming available. Indeed, in addition to a nonspecific treatment and to the immunosuppression that has the aim to block the auto antibodies production, the specific inhibition of complement activation is relatively new and may act either blocking the C5 convertase or the C3 convertase. The drugs acting on C3 convertase are still in different phases of clinical development and might represent drugs for the future. Overall the authors consider that one of the principal problems in finding new types of drugs are both the rarity of the disease and the consequent poor interest in the marketing and the lack of large international cooperative studies. PMID:27458560

  13. Autoantibodies to ribosomal P antigens with immune complex glomerulonephritis in SJL mice treated with pristane.

    PubMed

    Satoh, M; Hamilton, K J; Ajmani, A K; Dong, X; Wang, J; Kanwar, Y S; Reeves, W H

    1996-10-01

    BALB/c ByJ mice develop a lupus-like syndrome characterized by anti-nRNP/Sm and Su autoantibodies and immune complex glomerulonephritis after a single i.p. pristane injection. In contrast, mercuric chloride induces anti-fibrillarin Abs only in SJL and other H-2s mice, and not in BALB/c (H-2d) mice. In the present study, the specificities of autoantibodies induced by pristane and HgCl2 were compared in SJL and BALB/c mice to examine whether these strains are "programmed" to make different sets of autoantibodies in response to nonspecific immune stimulation. Unexpectedly, the predominant autoantibodies induced by pristane in SJL mice were neither those characteristic of HgCl2-treated SJL mice nor those associated with pristane-induced disease in BALB/c mice but, rather, anti-ribosomal P, another lupus-related specificity. The autoantibodies were strongly reactive with the C-terminal 22 amino acids of the ribosomal P2 protein, indicating that they exhibited similar fine specificities to anti-P Abs in human SLE and MRL/Ipr mice. Like BALB/c mice, pristane-treated SJL mice developed severe glomerulonephritis characterized by proteinuria, mesangial proliferation, and glomerular immune complex deposits. This is the first evidence that the induction of a lupus-like syndrome by pristane is not restricted to BALB/c mice. The predominance of anti-P Abs in SJL mice contrasts sharply with the predominance of anti-nRNP/Sm and Su, in pristane-treated BALB/c mice, even though the renal lesions were similar in both strains. The data suggest that H-2s does not program mice to produce anti-fibrillarin Abs in response to nonspecific immune stimulation, arguing that autoantibody induction by pristane involves Ag-specific mechanisms. PMID:8816434

  14. Anaerococcus urinomassiliensis sp. nov., isolated from a urine sample of a 17-year-old boy affected by autoimmune hepatitis and membranoproliferative glomerulonephritis.

    PubMed

    Morand, A; Cornu, F; Tsimaratos, M; Lagier, J-C; Cadoret, F; Fournier, P-E; Raoult, D

    2016-09-01

    We report the main characteristics of 'Anaerococcus urinomassiliensis' strain FC4(T) (CSURP2143) that was isolated from a urine sample of a 17-year-old boy affected by autoimmune hepatitis and membranoproliferative glomerulonephritis. PMID:27408746

  15. Streptococcal acute pharyngitis.

    PubMed

    Anjos, Lais Martins Moreira; Marcondes, Mariana Barros; Lima, Mariana Ferreira; Mondelli, Alessandro Lia; Okoshi, Marina Politi

    2014-07-01

    Acute pharyngitis/tonsillitis, which is characterized by inflammation of the posterior pharynx and tonsils, is a common disease. Several viruses and bacteria can cause acute pharyngitis; however, Streptococcus pyogenes (also known as Lancefield group A β-hemolytic streptococci) is the only agent that requires an etiologic diagnosis and specific treatment. S. pyogenes is of major clinical importance because it can trigger post-infection systemic complications, acute rheumatic fever, and post-streptococcal glomerulonephritis. Symptom onset in streptococcal infection is usually abrupt and includes intense sore throat, fever, chills, malaise, headache, tender enlarged anterior cervical lymph nodes, and pharyngeal or tonsillar exudate. Cough, coryza, conjunctivitis, and diarrhea are uncommon, and their presence suggests a viral cause. A diagnosis of pharyngitis is supported by the patient's history and by the physical examination. Throat culture is the gold standard for diagnosing streptococcus pharyngitis. However, it has been underused in public health services because of its low availability and because of the 1- to 2-day delay in obtaining results. Rapid antigen detection tests have been used to detect S. pyogenes directly from throat swabs within minutes. Clinical scoring systems have been developed to predict the risk of S. pyogenes infection. The most commonly used scoring system is the modified Centor score. Acute S. pyogenes pharyngitis is often a self-limiting disease. Penicillins are the first-choice treatment. For patients with penicillin allergy, cephalosporins can be an acceptable alternative, although primary hypersensitivity to cephalosporins can occur. Another drug option is the macrolides. Future perspectives to prevent streptococcal pharyngitis and post-infection systemic complications include the development of an anti-Streptococcus pyogenes vaccine. PMID:25229278

  16. The Spitzer Mid-infrared AGN Survey. II. The Demographics and Cosmic Evolution of the AGN Population

    NASA Astrophysics Data System (ADS)

    Lacy, M.; Ridgway, S. E.; Sajina, A.; Petric, A. O.; Gates, E. L.; Urrutia, T.; Storrie-Lombardi, L. J.

    2015-04-01

    We present luminosity functions derived from a spectroscopic survey of active galactic nuclei (AGNs) selected from Spitzer Space Telescope imaging surveys. Selection in the mid-infrared is significantly less affected by dust obscuration. We can thus compare the luminosity functions of obscured and unobscured AGNs in a more reliable fashion than by using optical or X-ray data alone. We find that the AGN luminosity function can be well described by a broken power-law model in which the break luminosity decreases with redshift. At high redshifts (z\\gt 1.6), we find significantly more AGNs at a given bolometric luminosity than found by either optical quasar surveys or hard X-ray surveys. The fraction of obscured AGNs decreases rapidly with increasing AGN luminosity, but, at least at high redshifts, appears to remain at ≈ 50% even at bolometric luminosities ˜ {{10}14} {{L}⊙ }. The data support a picture in which the obscured and unobscured populations evolve differently, with some evidence that high luminosity obscured quasars peak in space density at a higher redshift than their unobscured counterparts. The amount of accretion energy in the universe estimated from this work suggests that AGNs contribute about 12% to the total radiation intensity of the universe, and a high radiative accretion efficiency ≈ 0.18-0.07+0.12 is required to match current estimates of the local mass density in black holes.

  17. Role of reconnection in AGN jets

    NASA Astrophysics Data System (ADS)

    Lyutikov, Maxim

    2003-10-01

    We discuss the possible role of reconnection in electro-magnetically dominated cores of relativistic AGN jets. We suggest that reconnection may proceed in a two-fold fashion: initial explosive collapse on the Alfvén time-scale of a current-carrying jet (which is of the order of the light crossing time) and subsequent slow quasi-steady reconnection. Sites of explosive collapse are associated with bright knots, while steady-state reconnection re-energizes particles in the 'bridges' between the knots. Ohmic dissipation in reconnection layers leads to particle acceleration either by inductive electric fields or by stochastic particle acceleration in the ensuing electro-magnetic turbulence.

  18. X-ray AGN in the XMM-LSS galaxy clusters: no evidence of AGN suppression

    NASA Astrophysics Data System (ADS)

    Koulouridis, E.; Plionis, M.; Melnyk, O.; Elyiv, A.; Georgantopoulos, I.; Clerc, N.; Surdej, J.; Chiappetti, L.; Pierre, M.

    2014-07-01

    We present a study of the overdensity of X-ray-selected active galactic nuclei (AGN) in 33 galaxy clusters in the XMM-LSS field (The XMM-Newton Large Scale Structure Survey), up to redshift z = 1.05 and further divided into a lower (0.14 ≤ z ≤ 0.35) and a higher redshift (0.43 ≤ z ≤ 1.05) subsample. Previous studies have shown that the presence of X-ray-selected AGN in rich galaxy clusters is suppressed, since their number is significantly lower than what is expected from the high galaxy overdensities in the area. In the current study we have investigated the occurrence of X-ray-selected AGN in low (⟨ Lx,bol ⟩ = 2.7 × 1043 erg/s) and moderate (⟨ Lx,bol ⟩ = 2.4 × 1044 erg/s) X-ray luminosity galaxy clusters in an attempt to trace back the relation between high-density environments and nuclear activity. Owing to the wide contiguous XMM-LSS survey area, we were able to extend the study to the cluster outskirts. We therefore determined the projected overdensity of X-ray point-like sources around each cluster out to 6r500 radius, within δr500 = 1 annulus, with respect to the field expectations based on the X-ray source log N - log S of the XMM-LSS field. To provide robust statistical results we also conducted a consistent stacking analysis separately for the two z ranges. We investigated whether the observed X-ray overdensities are to be expected thanks to the obvious enhancement of galaxy numbers in the cluster environment by also estimating the corresponding optical galaxy overdensities, and we assessed the possible enhancement or suppression of AGN activity in clusters. We find a positive X-ray projected overdensity in both redshift ranges at the first radial bins, which however has the same amplitude as that of optical galaxies. Therefore, no suppression (or enhancement) of X-ray AGN activity with respect to the field is found, in sharp contrast to previous results based on rich galaxy clusters, implying that the mechanisms responsible for the

  19. The KMOS AGN Survey at High Redshift (KASHz)

    NASA Astrophysics Data System (ADS)

    Harrison, C.; Alexander, D.; Mullaney, J.; Stott, J.; Swinbank, M.; Arumugam, V.; Bauer, F.; Bower, R.; Bunker, A.; Sharples, R.

    2016-03-01

    The KMOS AGN Survey at High Redshift (KASHz) is an extensive observational programme to obtain spatially resolved spectroscopy of distant galaxies that host rapidly growing supermassive black holes (i.e., active galactic nuclei [AGN]). By exploiting the unique capabilities of KMOS we will spatially resolve the ionised gas kinematics in around 200 such galaxies. A fundamental prediction of galaxy formation models is that AGN inject considerable energy into their host galaxies and ultimately destroy or remove star-forming material via outflows. However, until now, observational constraints of this prediction have been limited to only a small number of distant galaxies. KASHz will provide the strongest constraints to date on the prevalence, properties and impact of ionised outflows in the host galaxies of distant AGN. The survey is described and our first results presented.

  20. Completing the AGN Census for Nearby Galaxies (Archival Component)

    NASA Astrophysics Data System (ADS)

    Ho, Luis

    2010-09-01

    The census of AGNs in the local Universe provides an efficient and effective estimate of the occupation fraction of central black holes in galaxies. While the demographics of AGNs in bulge-dominated systems is fairly well known, the situation in later-type galaxies is still murky because of potential optical selection biases. Searching for X-ray cores using Chandra can bypass these complications. We propose to complete the local AGN census by surveying all 188 star-forming (H II) nuclei in the well-studied Palomar sample of nearby galaxies. We request funding to analyze the 85 objects already in the archive; new observations have been proposed for the rest. We will establish with unprecedented reliability the AGN fraction across a wide range in Hubble type and Eddington ratios.

  1. Broad Band Properties of the BAT Selected AGN

    NASA Technical Reports Server (NTRS)

    Mushotzky, Richard; Winter, Lisa; Tueller, jack

    2008-01-01

    We will present the x-ray spectral properties of approximately 150 Burst Alert Telescope (BAT) selected active galactic nuclei (AGN) focusing on the issues of spectral complexity, x-ray absorption and its distribution and that contribution of sources to the x-ray background. If time permits we will also present the nature of the host galaxies of the AGN and their relationship to merger candidates.

  2. The bulge-disc decomposition of AGN host galaxies

    NASA Astrophysics Data System (ADS)

    Bruce, V. A.; Dunlop, J. S.; Mortlock, A.; Kocevski, D. D.; McGrath, E. J.; Rosario, D. J.

    2016-05-01

    We present the results from a study of the morphologies of moderate luminosity X-ray-selected active galactic nuclei (AGN) host galaxies in comparison to a carefully mass-matched control sample at 0.5 < z < 3 in the CANDELS GOODS-S field. We apply a multiwavelength morphological decomposition analysis to these two samples and report on the differences between the morphologies as fitted from single Sérsic and multiple Sérsic models, and models which include an additional nuclear point-source component. Thus, we are able to compare the widely adopted single Sérsic fits from previous studies to the results from a full morphological decomposition, and address the issue of how biased the inferred properties of AGN hosts are by a potential nuclear contribution from the AGN itself. We find that the AGN hosts are indistinguishable from the general galaxy population except that beyond z ≃ 1.5 they have significantly higher bulge fractions. Even including nuclear sources in our modelling, the probability of this result arising by chance is ˜1 × 10-5, alleviating concerns that previous, purely single Sérsic, analyses of AGN hosts could have been spuriously biased towards higher bulge fractions. This data set also allows us to further probe the physical nature of these point-source components; we find no strong correlation between the point-source component and AGN activity. Our analysis of the bulge and disc fractions of these AGN hosts in comparison to a mass-matched control sample reveals a similar morphological evolutionary track for both the active and non-active populations, providing further evidence in favour of a model where AGN activity is triggered by secular processes.

  3. Young AGN Outburst Running over Older X-Ray Cavities

    NASA Astrophysics Data System (ADS)

    Bogdan, Akos; van Weeren, Reinout Johannes; Kraft, Ralph; Forman, William; Scott, Randall; Giacintucci, Simona; Churazov, Eugene; O'Dea, Christopher; Baum, Stefi; Noell-Storr, Jacob; Jones, Christine

    2015-08-01

    Although the energetic feedback from active galactic nuclei (AGNs) is believed to have a profound effect on the evolution of galaxies and clusters of galaxies, details of AGN heating remain elusive. Here, we study NGC 193 -- a nearby lenticular galaxy in a group -- based on X-ray and radio observations. These data reveal the complex AGN outburst history of the galaxy: we detect a pair of inner X-ray cavities, an outer X-ray cavity, a shock front, and radio lobes extending beyond the inner cavities. We suggest that the inner cavities were produced about 78 Myr ago by a weaker AGN outburst, while the outer cavity, the radio lobes, and the shock front are due to a younger (13-26 Myr) and 4-8 times more powerful outburst. Combining this with the observed morphology of NGC 193, we conclude that NGC 193 likely represents the first example of a second, more powerful, AGN outburst overrunning an older, weaker outburst. These results help us to understand how the outburst energy is dissipated uniformly in the core of galaxies, and therefore may play a crucial role in resolving how AGN outbursts suppress the formation of large cooling flows at cluster centers.

  4. A Herschel View on Galaxy/AGN Co-Evolution

    NASA Astrophysics Data System (ADS)

    Lutz, D.; Pep Consortium

    2011-10-01

    Deep far-infrared photometric surveys studying galaxy evolution and the nature of the cosmic infrared background are a key strength of the Herschel mission. The PACS Evolutionary Probe (PEP) guaranteed time key program obtains deep photometric surveys of some of the key extragalactic multiwavelength fields at wavelengths between 70 and 160μm. This contribution gives an overview of first science results, illustrating the potential of Herschel in providing calorimetric star formation rates for various high redshift galaxy populations, thus testing and superseding previous extrapolations from other wavelengths, and enabling a wide range of galaxy evolution studies. Herschel measured star formation rates of high redshift X-ray AGN suggest an interplay between two paths of AGN/host coevolution. A correlation of AGN luminosity and host star formation is traced locally over a wide range of luminosities and also extends to luminous high-z AGN. This correlation reflects an evolutionary connection, likely via merging. For lower AGN luminosities, star formation is similar to that in non-active massive galaxies and shows little dependence on AGN luminosity. The level of this secular, non-merger driven star formation increasingly dominates over the correlation at increasing redshift.

  5. Mini-Survey Of SDSS of [OIII] AGN With Swift

    NASA Technical Reports Server (NTRS)

    Angelini, L.; George, I. M.; Hill, J.; Padgett, C. A.; Mushotzky, R. F.

    2008-01-01

    The number of AGN and their luminosity distribution are crucial parameters for our understanding of the AGN phenomenon. Recent work (e.g. Ferrarese and Merritt 2000) strongly suggests every massive galaxy has a central black hole. However, most of these objects either are not radiating or have been very difficult to detect. We are now in the era of large surveys, and the luminosity function (LF) of AGN has been estimated in various ways. In the X-ray band, Chandra and XMM surveys (e.g., Barger et al. 2005; Hasinger, et al. 2005) have revealed that the LF of Hard X-ray selected AGN shows a strong luminosity-dependent evolution with a dramatic break towards low L(x) (at al z). This is seen for all types of AGN, but is stronger for the broad-line objects (e.g., Steffen et al. 2004). In sharp contrast, the local LF of optically-selected samples shows no such break and no differences between narrow and broad-line objects (Hao et al. 2005). If, as been suggested, hard X-ray and optical emission line can both be fair indicators of AGN activity, it is important to first understand how reliable these characteristics are if we hope to understand the apparent discrepancy in the LFs.

  6. Modeling IR SED of AGN with Spitzer and Herschel data

    NASA Astrophysics Data System (ADS)

    Feltre, A.

    2012-12-01

    One of the remaining open issues in the context of the analysis of Active Galactic Nuclei (AGN) is the evidence that nuclear gravitational accretion is often accompanied by a concurrent starburst (SB) activity. What is, in this picture, the role played by the obscur- ing dust around the nucleus and what do the state of the art AGN torus models have to say? Can the IR data provided by Spitzer and Herschel help us in extensively investigate both phenomena and, if so, how and with what limitations? In this paper we present our contribution to the efforts of answering these questions. We show some of the main results coming from a comparative study of various AGN SED modeling approaches, focusing mostly on the much-debated issue about the morphology of the dust distribution in the toroidal structure surrounding the AGN. We found that the properties of dust in AGN as measured by matching observations (be it broad band IR photometry or IR spectra) with models, strongly depend on the choice of the dust distribution. Then, we present the spec- tral energy distribution (SED) fitting procedure we developed, making make the best use of Spitzer and Herschel SPIRE mid- and far-IR observations, to dig into the role played by the possible presence of an AGN on the host galaxy's properties.

  7. YOUNG AGN OUTBURST RUNNING OVER OLDER X-RAY CAVITIES

    SciTech Connect

    Bogdán, Ákos; Van Weeren, Reinout J.; Kraft, Ralph P.; Forman, William R.; Randall, Scott; Jones, Christine; Giacintucci, Simona; Churazov, Eugene; O'Dea, Christopher P.; Baum, Stefi A.; Noell-Storr, Jacob

    2014-02-20

    Although the energetic feedback from active galactic nuclei (AGNs) is believed to have a profound effect on the evolution of galaxies and clusters of galaxies, details of AGN heating remain elusive. Here, we study NGC 193—a nearby lenticular galaxy—based on X-ray (Chandra) and radio (Very Large Array and Giant Meter-wave Radio Telescope) observations. These data reveal the complex AGN outburst history of the galaxy: we detect a pair of inner X-ray cavities, an outer X-ray cavity, a shock front, and radio lobes extending beyond the inner cavities. We suggest that the inner cavities were produced ∼78 Myr ago by a weaker AGN outburst, while the outer cavity, the radio lobes, and the shock front are due to a younger (13-26 Myr) and 4-8 times more powerful outburst. Combining this with the observed morphology of NGC 193, we conclude that NGC 193 likely represents the first example of a second, more powerful, AGN outburst overrunning an older, weaker outburst. These results help us to understand how the outburst energy is dissipated uniformly in the core of galaxies, and therefore may play a crucial role in resolving how AGN outbursts suppress the formation of large cooling flows at cluster centers.

  8. On the physical origin of AGN outflow driving mechanisms

    NASA Astrophysics Data System (ADS)

    Ishibashi, Wako

    2016-07-01

    Super-massive black holes in active galactic nuclei (AGN) respond to the accretion process by feeding back energy and momentum into the surrounding environment. Galaxy-scale outflows are thought to provide the physical link connecting the small scales of the central black hole to the large scales of the host galaxy. Such powerful outflows are now starting to be commonly observed, and have been considered as a proof of AGN feedback in action. However, the physical origin of the mechanism driving the observed outflows is still unclear, and whether it is due to energy-driving or radiation-driving is a source of much debate in the literature. We consider AGN feedback driven by radiation pressure on dust, and show that AGN radiative feedback is capable of driving powerful outflows on galactic scales. In particular, we can obtain outflowing shells with high velocity and large momentum flux, by properly taking into account the effects of radiation trapping. Alternatively, the observed outflow characteristics may be significantly biased by AGN variability. I will discuss the resulting implications in the global context of black hole accretion-AGN feedback coupling.

  9. Postinfectious glomerulonephritis secondary to Erythrovirus B19 (Parvovirus B19): case report and review of the literature.

    PubMed

    Marco, Helena; Guermah, Imane; Matas, Lurdes; Hernández, Alba; Navarro, Maruja; Lopez, Dolores; Bonet, Josep

    2016-04-01

    A previously healthy 32-yearold woman developed arterial hypertension, proteinuria, and hematuria (nephritic syndrome) with normal renal function and was diagnosed with post-infectious glomerulonephritis secondary to parvovirus B19 infection. The renal biopsy showed endocapillary glomerulonephritis, with positive IgG, C3, and C1q immunoreactivity in the capillary walls and ultrastructural evidence of subendothelial deposits. The diagnosis of parvovirus B19 infection was confirmed by IgG/IgM serological positivity and parvovirus DNA demonstration in both peripheral blood and kidney tissue. Glomerular involvement improved spontaneously. To be noted are the atypical signs and symptoms of our patient who, unlike previously reported cases, failed to show fever, skin rash, or affected relatives. PMID:26833301

  10. Proteomics and glomerulonephritis: A complementary approach in renal pathology for the identification of chronic kidney disease related markers.

    PubMed

    L'Imperio, Vincenzo; Smith, Andrew; Chinello, Clizia; Pagni, Fabio; Magni, Fulvio

    2016-04-01

    Glomerulonephritis (GN) is one of the most common origins of chronic kidney disease and its careful evaluation is crucial for prognostic and therapeutic purposes, with the renal biopsy still playing a central role for the diagnosis. However, due to its invasiveness, it is not devoid of complications and many investigations have focused on identifying biomarkers for chronic kidney diseases using less-invasive and easy-to-collect samples, such as urine and blood. In this context, proteomics has played a crucial role in determining the molecular changes related to disease progression and early pathological glomerular modifications. Here, we report a review of selected literature for each GN, based on selected works published in the last 10 years, showing how these approaches have generated clinically relevant findings in the study of glomerulonephritis. We also describe several proteomic strategies, highlighting their technical advantages and limitations, future perspectives for proteomic applications in the study of GNs, and their possible application in routine practice. PMID:26642820

  11. The complete census of optically selected AGNs in the Coma supercluster: the dependence of AGN activity on the local environment

    NASA Astrophysics Data System (ADS)

    Gavazzi, G.; Savorgnan, G.; Fumagalli, Mattia

    2011-10-01

    Aims: To investigate the dependence of the occurrence of active galactic nuclei (AGNs) on local galaxy density, we study the nuclear properties of ~5000 galaxies in the Coma supercluster whose density spans two orders of magnitude from the sparse filaments to the cores of rich clusters. Methods: We obtained optical spectra of the nuclei of 283 galaxies using the 1.5 m Cassini telescope of Bologna observatory. Among these galaxies, 177 belong to the Coma supercluster and are added to the 4785 spectra available from SDSS (DR7) to fill-in the incomplete coverage by SDSS of luminous galaxies. We perform a spectral classification of the nuclei of galaxies in this region (with a completeness of 98% at r ≤ 17.77), classifying the nuclear spectra in six classes: three of them (SEY, sAGN, LIN) refer to AGNs and the remaining three (HII, RET, PAS) refer to different stages of starburst activity. We perform this classification as recommended by Cid Fernandes and collaborators using the ratio of λ 6584 [NII] to Hα lines and the equivalent width of Hα (WHAN diagnostic), after correcting the last quantity by 1.3 Å for underlying absorption. Results: We find that 482 (10%) of 5027 galaxies host an AGN: their frequency strongly increases with increasing luminosity of the parent galaxies, such that 32% of galaxies with Log(Li/L⊙) ≥ 10.2 harbor an AGN at their interior. In addition to their presence in luminous galaxies, AGNs are also found in red galaxies with ⟨g - i⟩ ≃ 1.15 ± 0.15 mag. The majority of SEY and sAGN (strong AGNs) are associated with luminous late-type (or S0a) galaxies, while LIN (weak AGNs) and RET ("retired": nuclei that have experienced a starburst phase in the past and are now ionized by their hot evolved low-mass stars), are mostly found among E/S0as. The number density of AGNs, HII region-like, and retired galaxies is found to anti-correlate with the local density of galaxies, such that their frequency drops by a factor of two near the cluster

  12. SUPERNOVAE AND AGN DRIVEN GALACTIC OUTFLOWS

    SciTech Connect

    Sharma, Mahavir; Nath, Biman B. E-mail: biman@rri.res.in

    2013-01-20

    We present analytical solutions for winds from galaxies with a Navarro-Frank-White (NFW) dark matter halo. We consider winds driven by energy and mass injection from multiple supernovae (SNe), as well as momentum injection due to radiation from a central black hole. We find that the wind dynamics depends on three velocity scales: (1) v{sub *}{approx}( E-dot / 2 M-dot ){sup 1/2} describes the effect of starburst activity, with E-dot and M-dot as energy and mass injection rate in a central region of radius R; (2) v {sub .} {approx} (GM {sub .}/2R){sup 1/2} for the effect of a central black hole of mass M {sub .} on gas at distance R; and (3) v{sub s}=(GM{sub h} / 2Cr{sub s}){sup 1/2}, which is closely related to the circular speed (v{sub c} ) for an NFW halo, where r{sub s} is the halo scale radius and C is a function of the halo concentration parameter. Our generalized formalism, in which we treat both energy and momentum injection from starbursts and radiation from the central active galactic nucleus (AGN), allows us to estimate the wind terminal speed to be (4v {sup 2} {sub *} + 6({Gamma} - 1)v {sub .} {sup 2} - 4v {sup 2} {sub s}){sup 1/2}, where {Gamma} is the ratio of force due to radiation pressure to gravity of the central black hole. Our dynamical model also predicts the following: (1) winds from quiescent star-forming galaxies cannot escape from 10{sup 11.5} M {sub Sun} {<=} M{sub h} {<=} 10{sup 12.5} M {sub Sun} galaxies; (2) circumgalactic gas at large distances from galaxies should be present for galaxies in this mass range; (3) for an escaping wind, the wind speed in low- to intermediate-mass galaxies is {approx}400-1000 km s{sup -1}, consistent with observed X-ray temperatures; and (4) winds from massive galaxies with AGNs at Eddington limit have speeds {approx}> 1000 km s{sup -1}. We also find that the ratio [2v {sup 2} {sub *} - (1 - {Gamma})v {sub .} {sup 2}]/v {sup 2} {sub c} dictates the amount of gas lost through winds. Used in conjunction with

  13. Renal interstitial mast cell count is significantly higher in membranoproliferative glomerulonephritis than in class IV lupus nephritis.

    PubMed

    Kaczmarczyk, Karolina; Musiał, Jacek; Soja, Jerzy; Kuźniewski, Marek; Gala-Błądzińska, Agnieszka; Białas, Magdalena; Okoń, Krzysztof

    2015-06-01

    Lupus nephritis (LN) is a severe manifestation of systemic lupus erythematosus; in LN class IV morphologic lesions may be similar to the lesions in primary membranoproliferative glomerulonephritis (MPGN). The aim of the study was to compare the counts of tryptase-positive and chymase-positive mast cells between LN class IV and MPGN. The material consisted of 61 renal biopsies: 32 with lupus nephritis class IV, and 29 with membranoproliferative glomerulonephritis. Chymase- and tryptase-positive cells were stained by immunohistochemistry and subsequently counted. The mean count of chymase-positive mast cells was 21.94 for the whole group, 12.66 for LN class IV and 32.18 for MPGN. The mean count of tryptase-positive cells was 34.94 hpf for the entire group, 22.98 for LN class IV and 48. 13 for MPGN. The differences between lupus nephritis and membranoproliferative glomerulonephritis were significant both for chymase- and tryptase-positive cells. Both chymase-positive MC counts and tryptase-positive MC counts correlated with relative interstitial volume (RIV) (R=0.35 and R=0.28, respectively) and with creatinine level (R=0.35 and R=0.43, respectively). There was also a significant correlation between age, creatinine level and RIV (R=0.28 and R=0.26, respectively). PMID:26247528

  14. Fibrillary glomerulonephritis with small fibrils in a patient with the antiphospholipid antibody syndrome successfully treated with immunosuppressive therapy

    PubMed Central

    Javaid, Muhammad M; Denley, Helen; Tagboto, Senyo

    2007-01-01

    Background Fibrillary glomerulonephritis is a rare cause of progressive renal dysfunction, often leading to the need for dialysis within a few years. The role of immunosuppressive treatment is still uncertain although this has been tried with variable success. Case presentation A 56 year old woman with the antiphospholipid antibody syndrome (IgM anticardiolipin antibodies) was seen in the nephrology clinic with haematuria, proteinuria, and worsening renal function. A renal biopsy demonstrated a mesangial proliferative glomerulonephritis on light microscopy and smaller fibrils (10.6–13.8 nm in diameter) than is usual for fibrillary glomerulonephritis (typically 18–22 nm) on electron microscopy. Amyloidosis was excluded following detailed evaluation. On account of rapidly worsening renal failure she was started on cyclophosphamide and prednisolone which led to the partial recovery and stabilization of her renal function. Conclusion This case highlights the need for routine electron microscopy in native renal biopsies, where the differential diagnosis is wide and varied and the light and immunofluorescence microscopic findings may be non specific. PMID:17490479

  15. On the Importance of Very Light Internally Subsonic AGN Jets in Radio-mode AGN Feedback

    NASA Astrophysics Data System (ADS)

    Guo, Fulai

    2016-07-01

    Radio-mode active galactic nucleus (AGN) feedback plays a key role in the evolution of galaxy groups and clusters. Its physical origin lies in the kiloparsec-scale interaction of AGN jets with the intracluster medium. Large-scale jet simulations often initiate light internally supersonic jets with density contrast 0.01 < η < 1. Here we argue for the first time for the importance of very light (η < 0.01) internally subsonic jets. We investigated the shapes of young X-ray cavities produced in a suite of hydrodynamic simulations, and found that bottom-wide cavities are always produced by internally subsonic jets, while internally supersonic jets inflate cylindrical, center-wide, or top-wide cavities. We found examples of real cavities with shapes analogous to those inflated in our simulations by internally subsonic and internally supersonic jets, suggesting a dichotomy of AGN jets according to their internal Mach numbers. We further studied the long-term cavity evolution, and found that old cavities resulted from light jets spread along the jet direction, while those produced by very light jets are significantly elongated along the perpendicular direction. The northwestern ghost cavity in Perseus is pancake shaped, providing tentative evidence for the existence of very light jets. Our simulations show that very light internally subsonic jets decelerate faster and rise much slower in the intracluster medium than light internally supersonic jets, possibly depositing a larger fraction of jet energy to cluster cores and alleviating the problem of low coupling efficiencies found previously. The internal Mach number points to the jet’s energy content, and internally subsonic jets are energetically dominated by non-kinetic energy, such as thermal energy, cosmic rays, or magnetic fields.

  16. Mini Survey of SDSS [OIII] AGN with Swift: Testing the Hypothesis that L(sub [OIII]) Traces AGN Luminosity

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The number of AGN and their luminosity distribution are crucial parameters for our understanding of the AGN phenomenon. Recent work strongly suggests every massive galaxy has a central black hole. However most of these objects either are not radiating or have been very difficult to detect We are now in the era of large surveys, and the luminosity function (LF] of AGN has been estimated in various ways. In the X-ray band. Chandra and XMM surveys have revealed that the LF of hard X-ray selected AGN shows a strong luminosity-dependent evolution with a dramatic break towards low L(sub x) (at all z). This is seen for all types of AGN, but is stronger for the broad-line objects. In sharp contrast, the local LF of optically-selected samples shows no such break and no differences between narrow and broad-line objects. If as been suggested, hard X ray and optical emission line can both can be fair indicators of AGN activity, it is important to first understand how reliable these characteristics are if we hope to understand the apparent discrepancy in the LFs.

  17. Th1, Th2 and Treg/T17 cytokines in two types of proliferative glomerulonephritis.

    PubMed

    Stangou, M; Bantis, C; Skoularopoulou, M; Korelidou, L; Kouloukouriotou, D; Scina, M; Labropoulou, I T; Kouri, N M; Papagianni, A; Efstratiadis, G

    2016-01-01

    IgA nephropathy (IgAN) and focal segmental necrotizing glomerulonephritis (FSNGN) are characterized by proliferation of native glomerular cells and infiltration by inflammatory cells. Several cytokines act as mediators of kidney damage in both diseases. The aim of the present study was to investigate the role of Th1, Th2 and Treg/T17 cytokines in these types of proliferative glomerulonephritis. Simultaneous measurement of Th1 interleukin (IL-2, IL-12, tumor necrosis factor-alpha [TNF-α], interferon-gamma [INF-γ]), Th2 (IL-4, IL-5, IL-6, IL-10, IL-13), Treg/T17 transforming growth factor-beta 1 (TGF-β1, granulocyte-macrophage colony-stimulating factor [GM-CSF], IL-17) cytokines and C-C chemokines Monocyte chemoattractant protein-1 (MCP-1, macrophage inflammatory protein-1 [MIP-1] β) was performed in first-morning urine samples, at the day of renal biopsy, using a multiplex cytokine assay. Cytokine concentrations were correlated with histological findings and renal function outcome. Urinary excretion of Th1, Th2 and Treg/Th17 cytokines were significantly higher in FSNGN compared to IgAN patients. In IgAN patients (n = 50, M/F: 36/14, M age: 40.7 [17-67] years), Th1, Th2 and T17 cytokines correlated significantly with the presence of endocapillary proliferation, while in FSNGN patients (n = 40, M/F: 24/16, M age: 56.5 [25-80] years), MCP-1 and TGF-β1 had a positive correlation with severe extracapillary proliferation (P = 0.001 and P = 0.002, respectively). Urinary IL-17 was the only independent parameter associated with endocapillary proliferation in IgAN and with MCP-1 urinary excretion in FSNGN. Response to treatment was mainly predicted by IL-6 in IgAN, and by Th2 (IL-4, IL-6), Treg (GM-CSF) cytokines and MIP-1 β in FSNGN. Th1, Th2 and T17 cytokines were directly implicated in renal pathology in IgAN and possibly through MCP-1 production in FSNGN. IL-17 and IL-6 seem to have a central role in inflammation and progression of kidney injury. PMID:27194829

  18. Expression of alternatively spliced fibronectin variants during remodeling in proliferative glomerulonephritis.

    PubMed Central

    Barnes, J. L.; Torres, E. S.; Mitchell, R. J.; Peters, J. H.

    1995-01-01

    Fibronectin (Fn) plays an important role in tissue remodeling during embryogenesis, wound repair, and vascular disease, and is thought to regulate cellular processes such as cell adhesion, migration, proliferation, and differentiation through specialized domains within the molecule. In addition, Fn can be alternatively spliced at three regions: extradomains EIIIA, EIIIB, and a variable segment V, potentially giving rise to functionally distinct variants of the molecule. We have previously shown a sequential expression of cellular Fn first by platelets, followed by macrophages, then mesangial cells in habu snake venom-induced proliferative glomerulonephritis (Am J Pathol 145: 585-597, 1994). These studies examined the cellular sources and glomerular localization of Fn in general but did not distinguish between the various alternatively spliced isoforms. In this study, we examine by in situ hybridization and immunohistochemistry the temporal expression and cellular sources of EIIIA, EIIIB, and V in a model of proliferation glomerulonephritis that has cell migration, proliferation, and extracellular matrix synthesis as features of tissue remodeling. Macrophages were the first cells to express Fn mRNA showing an EIIIA+, EIIIB-, and V95+ pattern beginning at 8 hours after habu snake venom injection. Migrating mesangial cells at the margins of early lesions (8 and 24 hours) did not overexpress mRNA encoding these Fn variants, but immunofluorescence microscopy revealed V95 and EIIIA protein at the margins of lesions. EIIIB was absent in lesions at this time. At 48 hours and peaking at 72 hours after habu snake venom injection, mesangial cells in central aspects of glomerular lesions expressed abundant mRNA and protein for V95 and EIIIA. EIIIB mRNA and protein was slight in the mesangium at these times. Parietal epithelial cells, particularly adjacent to glomerular lesions, also expressed abundant mRNA and protein for all three variants throughout the course of the disease

  19. Th1, Th2 and Treg/T17 cytokines in two types of proliferative glomerulonephritis

    PubMed Central

    Stangou, M.; Bantis, C.; Skoularopoulou, M.; Korelidou, L.; Kouloukouriotou, D.; Scina, M.; Labropoulou, I. T.; Kouri, N. M.; Papagianni, A.; Efstratiadis, G.

    2016-01-01

    IgA nephropathy (IgAN) and focal segmental necrotizing glomerulonephritis (FSNGN) are characterized by proliferation of native glomerular cells and infiltration by inflammatory cells. Several cytokines act as mediators of kidney damage in both diseases. The aim of the present study was to investigate the role of Th1, Th2 and Treg/T17 cytokines in these types of proliferative glomerulonephritis. Simultaneous measurement of Th1 interleukin (IL-2, IL-12, tumor necrosis factor-alpha [TNF-α], interferon-gamma [INF-γ]), Th2 (IL-4, IL-5, IL-6, IL-10, IL-13), Treg/T17 transforming growth factor-beta 1 (TGF-β1, granulocyte-macrophage colony-stimulating factor [GM-CSF], IL-17) cytokines and C-C chemokines Monocyte chemoattractant protein-1 (MCP-1, macrophage inflammatory protein-1 [MIP-1] β) was performed in first-morning urine samples, at the day of renal biopsy, using a multiplex cytokine assay. Cytokine concentrations were correlated with histological findings and renal function outcome. Urinary excretion of Th1, Th2 and Treg/Th17 cytokines were significantly higher in FSNGN compared to IgAN patients. In IgAN patients (n = 50, M/F: 36/14, M age: 40.7 [17–67] years), Th1, Th2 and T17 cytokines correlated significantly with the presence of endocapillary proliferation, while in FSNGN patients (n = 40, M/F: 24/16, M age: 56.5 [25–80] years), MCP-1 and TGF-β1 had a positive correlation with severe extracapillary proliferation (P = 0.001 and P = 0.002, respectively). Urinary IL-17 was the only independent parameter associated with endocapillary proliferation in IgAN and with MCP-1 urinary excretion in FSNGN. Response to treatment was mainly predicted by IL-6 in IgAN, and by Th2 (IL-4, IL-6), Treg (GM-CSF) cytokines and MIP-1 β in FSNGN. Th1, Th2 and T17 cytokines were directly implicated in renal pathology in IgAN and possibly through MCP-1 production in FSNGN. IL-17 and IL-6 seem to have a central role in inflammation and progression of kidney injury. PMID:27194829

  20. Expression of AIM2 is high and correlated with inflammation in hepatitis B virus associated glomerulonephritis

    PubMed Central

    2013-01-01

    Background & aims Innate immunity is the first line of defense against invasive microbial infection, and AIM2 plays an important role in this process by sensing double-stranded DNA viruses. However, the role of AIM2 in regulating the immune response to viruses in vivo, especially in sensing hepatitis B virus (HBV), has not been examined. We hypothesized that the expression of AIM2 increases corresponding to HBV-mediated inflammation in patients with hepatitis B virus associated glomerulonephritis (HBV-GN), a condition which activates inflammatory mechanisms and causes renal damage. To test this hypothesis, we analyzed the expression of AIM2 in HBV-GN patients in relation to the inflammatory response to HBV infection. Methods A total of 79 patients diagnosed with chronic nephritis (CN) were enrolled in this study, including 54 HBV-GN patients as the experimental group and 24 chronic glomerulonephritis (CGN) patients as the negative control group. Six patients diagnosed with chronic hepatitis B (CHB) were also enrolled as positive controls. Each CN patient received renal biopsy, and immunohistochemistry was used to detect the expression of AIM2 and inflammatory factors caspase-1 and IL-1β in the biopsy specimens. CHB patients received liver puncture biopsy, and immunohistochemistry was used to detect the expression of AIM2 in these specimens. Expression of AIM 2 among different groups and in relation to inflammatory factors caspase-1 and IL-1β was analyzed. Results The expression of AIM2 in HBV-GN patients (81.4%) was significantly higher than in CGN patients (4.0%). Among the HBV-GN patients, expression of AIM2 was significantly higher in the high HBV replication group than in the low HBV replication group. AIM2 expression was not correlated with age, gender, HBeAg status in serum, HBV-antigen type deposited in renal tissue or pathological type of HBV-GN. However, AIM2 levels were positively correlated with the expression of caspase-1 and IL-1β in HBV-GN patients

  1. Reconfinement shocks in relativistic AGN jets

    SciTech Connect

    Nalewajko, Krzysztof; Sikora, Marek

    2008-12-24

    Stationary knots observed in many AGN jets can be explained in terms of a reconfinement shock that forms when relativistic flow of the jet matter collides with the external medium. The position of these knots can be used, together with information on external pressure profile, to constrain dynamical parameters of the jet. We present a semi-analytical model for the dynamical structure of reconfinement shocks, taking into account exact conservation laws both across the shock surface and in the zone of the shocked jet matter. We show that, due to the transverse pressure gradient in the shock zone, the position of the reconfinement is larger than predicted by simple models. A portion of kinetic energy is converted at the shock surface to internal energy, with efficiency increasing strongly with both bulk Lorentz factor of the jet matter and the jet half-opening angle. Our model may be useful as a framework for modeling non-thermal radiation produced within the stationary features.

  2. Spectropolarimetry of AGN, and `Women &\\ Science'

    NASA Astrophysics Data System (ADS)

    Kay, L.

    1999-12-01

    I have been using optical spectropolarimetry to investigate the nature of AGN. For the CAREER project, I have worked with A. M. Magalhães of the IAG in Brazil to use a visiting polarimetry module with the RC Spectrograph at CTIO, as well as conduct observations at Lick. Projects include observations of broad--line radio galaxies with double--peaked emission line profiles suggestive of accretion disks, and observations of a sample of X-ray selected narrow--line Seyfert 1 galaxies. Another project involves optical and X-ray observations of a complete sample of nearby Seyfert 2 galaxies in order to investigate the frequency of obscured broad--line regions and to determine their contribution to the X-ray background. In addition to involving undergraduate students in research, my educational efforts have focused on getting science into our Women's Studies program. I teach a course on the history and sociology of women in science, co-teach a course on feminist science studies, helped to create a course on women's health, organized a faculty seminar on gender and science issues, and lead a project at Barnard on gender and scientific literacy. I gratefully acknowledge support from NSF CAREER grant AST-9501835, as well as support from NSF International Research Fellowship INT-9423970, and from NSF grant EHR-9555808 to the AAC&U for the Gender and Scientific Literacy project.

  3. Oblique Shocks in AGN Jet Flows

    NASA Astrophysics Data System (ADS)

    Aller, H. D.; Aller, M. F.; Hughes, P. A.; Wardle, J. F. C.; Roberts, D. H.; Homan, D. C.

    2001-12-01

    We present multi-epoch VLBI images and single antenna monitoring results from a study of 10 highly variable AGNs (BL Lacs and QSOs) whose primary goal is to investigate the strengths and orientations of oblique shocks in relativistic flows by comparing observed polarized features found in VLBA total intensity and polarization images and UMRAO monitoring data with the predictions of simple oblique shock models which account for the effects of relativistic aberration. The data consist of weekly observations at 14.5, 8.0 and 4.8 GHz using the UMRAO 26-meter telescope, and seven sets of VLBA total flux and polarization images spaced over the past two years at 15 and 43 GHz supplemented by maps at 8 and 22 GHz for a subset known to exhibit significant opacity. The morphological evolution in both structure and polarization revealed by these data are used to provide an estimation of the projected flow deviation and magnetic field orientation at shocks, and initial results from a comparison of the data with newly developed radiative transfer models allowing for a range of shock orientations are presented. This work was supported in part by NSF grant AST-9900723. The UMRAO is supported by the University of Michigan; The National Radio Astronomy Observatory is operated by Associated Universities, Inc, under cooperative agreement with the National Science Foundation.

  4. Radio-Loud AGN: The Suzaku View

    NASA Technical Reports Server (NTRS)

    Sambruna, Rita

    2009-01-01

    We review our Suzaku observations of Broad-Line Radio Galaxies (BLRGs). The continuum above 2 approx.keV in BLRGs is dominated by emission from an accretion flow, with little or no trace of a jet, which is instead expected to emerge at GeV energies and be detected by Fermi. Concerning the physical conditions of the accretion disk, BLRGs are a mixed bag. In some sources the data suggest relatively high disk ionization, in others obscuration of the innermost regions, perhaps by the jet base. While at hard X-rays the distinction between BLRGs and Seyferts appears blurry, one of the cleanest observational differences between the two classes is at soft X-rays, where Seyferts exhibit warm absorbers related to disk winds while BLRGs do not. We discuss the possibility that jet formation inhibits disk winds, and thus is related to the remarkable dearth of absorption features at soft X-rays in BLRGs and other radio-loud AGN.

  5. Using AGN to Observe the Growth of the Cosmic Web

    NASA Astrophysics Data System (ADS)

    Murray, S.; Jones, C.; Forman, W.; Kenter, A.; Vihklinin, A.; Markevitch, M.; Brand, K.; Jannuzi, B.; Kochanek, C.; Eisenstein, D.

    We present X-ray and optical observations of the contiguous 9 3 sq deg XBootes survey made with the ACIS instrument on Chandra The X-ray survey consists of 126 5ksec pointings that achieve a sensitivity of about 4 times10 -15 erg cm -2 s -1 in the 0 5--7 keV band At this sensitivity limit we detect 4642 X-ray sources As part of the AGES galaxy survey in the Bootes region Kochanek et al 2005 we have obtained 1800 redshifts of the X-ray selected objects most of which are AGN yielding a density of sim150 AGN per square degree The mean AGN redshift is 1 3 with the distribution extending to z 4 We have analyzed the spatial distribution of the X-ray selected AGN and compared this to the distribution of the sim20000 AGES galaxies To z sim0 7 the limit of galaxy sample the galaxies and AGN both trace the same structures and show the same web of voids and filaments At larger redshifts the X-ray AGN continue to show the characteristic structure of voids and filaments Quantitatively we computed the spatial 2-point correlation function for the X-ray selected AGN and find that the correlation length r 0 simeq6 4 h -1 Mpc and the exponent gamma simeq-1 7 of the correlation function are similar to the canonical values derived for galaxies In addition we have compared the correlation function in several redshift intervals and find that the correlation length is approximately constant to z sim1 5

  6. The impact of AGN on their host galaxies

    NASA Astrophysics Data System (ADS)

    Harrison, C. M.

    2014-07-01

    In these proceedings I briefly: (1) review the impact (or ``feedback'') that active galactic nuclei (AGN) are predicted to have on their host galaxies and larger scale environment, (2) review the observational evidence for or against these predictions and (3) present new results on ionised outflows in AGN. The observational support for the ``maintenance mode'' of feedback is strong (caveat the details); AGN at the centre of massive halos appear to be regulating the cooling of hot gas, which could in turn control the levels of future star formation (SF) and black hole growth. In contrast, direct observational support for more rapid forms of feedback, which dramatically impact on SF (i.e., the ``quasar mode''), remains elusive. From a systematic study of the spectra of ~24 000 AGN we find that extreme ionised gas kinematics are common, and are most prevalent in radio bright AGN (L 1.4 GHz > 103 W Hz-1). Follow-up IFU observations have shown that these extreme gas kinematics are extended over kilo-parsec scales. However, the co-existence of high-levels of SF, luminous AGN activity and radio jets raises interesting questions on the primary drivers and impact of these outflows. Galaxy-wide, high-mass outflows are being observed in an increasing number of AGN and are a plausible mechanism for the depletion of gas; however, there is still much work to be done to determine the physical processes that drive these outflows and to measure the level of impact that they have on their host galaxies.

  7. SED and Emission Line Properties of Red 2MASS AGN

    NASA Astrophysics Data System (ADS)

    Kuraszkiewicz, Joanna; Wilkes, Belinda J.; Schmidt, Gary; Ghosh, Himel

    2009-09-01

    Radio and far-IR surveys, and modeling of the cosmic X-ray background suggest that a large population of obscured AGN has been missed by traditional, optical surveys. The Two Micron All-Sky Survey (2MASS) has revealed a large population (surface density comparable to that of optically selected AGN with Ks<14.5mag) of mostly nearby (median z=0.25), red, moderately obscured AGN, among which 75% are previously unidentified emission-line AGN, with 85% showing broad emission lines. We present the SED and emission line properties of 44 such red (J-Ks>2) 2MASS AGN observed with Chandra. They lie at z<0.37, span a full range of spectral types (Type 1, intermediate, Type 2),Ks-to-X-ray slopes, and polarization (<13%). Their IR-to-X-ray spectral energy distributions (SEDs) are red in the near-IR/opt/UV showing little or no blue bump. The optical colors are affected by reddening, host galaxy emission, redshift, and in few, highly polarized objects, also by scattered AGN light. The levels of obscuration obtained from optical, X-rays, and far-IR imply N_H AGN light. PCA analysis of the IR-X-ray SED and emission line properties shows that, while obscuration/inclination is important, the dominant cause of variance in the sample (eigenvector 1) is the L/L_{edd} ratio (perhaps because the red near-IR selection limits the range of inclination/obscuration values in our sample). This analysis also distinguishes two sources of obscuration: the host galaxy and circumnuclear absorption.

  8. AGN coronal emission models - I. The predicted radio emission

    NASA Astrophysics Data System (ADS)

    Raginski, I.; Laor, Ari

    2016-06-01

    Accretion discs in active galactic nucleus (AGN) may be associated with coronal gas, as suggested by their X-ray emission. Stellar coronal emission includes radio emission, and AGN corona may also be a significant source for radio emission in radio quiet (RQ) AGN. We calculate the coronal properties required to produce the observed radio emission in RQ AGN, either from synchrotron emission of power-law (PL) electrons, or from cyclosynchrotron emission of hot mildly relativistic thermal electrons. We find that a flat spectrum, as observed in about half of RQ AGN, can be produced by corona with a disc or a spherical configuration, which extends from the innermost regions out to a pc scale. A spectral break to an optically thin power-law emission is expected around 300-1000 GHz, as the innermost corona becomes optically thin. In the case of thermal electrons, a sharp spectral cut-off is expected above the break. The position of the break can be measured with very long baseline interferometry observations, which exclude the cold dust emission, and it can be used to probe the properties of the innermost corona. Assuming equipartition of the coronal thermal energy density, the PL electrons energy density, and the magnetic field, we find that the energy density in a disc corona should scale as ˜R-1.3, to get a flat spectrum. In the spherical case the energy density scales as ˜R-2, and is ˜4 × 10-4 of the AGN radiation energy density. In Paper II we derive additional constraints on the coronal parameters from the Gudel-Benz relation, Lradio/LX-ray ˜ 10- 5, which RQ AGN follow.

  9. Acute and Chronic Allograft Dysfunction in Kidney Transplant Recipients.

    PubMed

    Goldberg, Ryan J; Weng, Francis L; Kandula, Praveen

    2016-05-01

    Allograft dysfunction after a kidney transplant is often clinically asymptomatic and is usually detected as an increase in serum creatinine level with corresponding decrease in glomerular filtration rate. The diagnostic evaluation may include blood tests, urinalysis, transplant ultrasonography, radionuclide imaging, and allograft biopsy. Whether it occurs early or later after transplant, allograft dysfunction requires prompt evaluation to determine its cause and subsequent management. Acute rejection, medication toxicity from calcineurin inhibitors, and BK virus nephropathy can occur early or later. Other later causes include transplant glomerulopathy, recurrent glomerulonephritis, and renal artery stenosis. PMID:27095641

  10. Detecting AGNs using multi-filter imaging data

    NASA Astrophysics Data System (ADS)

    Dong, Xiaoyi

    2012-05-01

    The purpose of this research project was to develop and test a technique to detect active galactic nuclei, AGNs, using high quality, multi-filter imaging data alone. In order to perform a physically meaningful aperture photometric measurement, we have adapted an image manipulation method - shapelets. shapelets can remove the Point Spread Function (PSF) from an image without the traditional deconvolution in Fourier space. It can therefore be used to adjust the image PSF, i.e., to sharpen the PSF and to make each filter's PSF have the same full width at half maximum (FWHM). shapelets is realized by an IDL based package SHAPELETS, originally designed for studying weak gravitational lensing, and adjusted to suit our application. The primary data we used were selected from the CFHT Legacy Survey Wide Survey field W4. The sample included 6670 galaxies, with u magnitudes ≤ +22 mag, and inclinations ≤ 60°. We applied shapelets to each galaxy for each filter. The result was a shapelets reconstructed image with a 2-D Gaussian PSF with FWHM=3 pixels. We then made relevant photometric measurements on the reconstructed image. In order to calculate distance-dependent parameters such as the galaxy luminosity, we estimated the photometric redshift using an artificial neural network (ANN) with a root mean square (RMS) of 0.025. We designed another neural net to classify the galaxy morphological type based on its photometric properties. The classification was based on Nair and Abraham (2010), and has an accuracy < 2T types. Because galaxy colours alone cannot be used to distinguish AGNs from "normal" galaxies, we also designed a neural net to separate AGN, "normal" , and starforming/starburst galaxies. The accuracy of this classification technique is about 75%. Because our method relies largely on the spatial resolution of the data, we limited our analysis to z ≤ 0.1. The sample contained 1570 galaxies, and we detected 178 AGNs (11.3%), 176 "normal" (11.2%), and 1216

  11. Long-term follow-up of atypical membranoproliferative glomerulonephritis: are steroids indicated?

    PubMed

    Fujita, Teruo; Nozu, Kandai; Iijima, Kazumoto; Kamioka, Ichiro; Yoshiya, Kunihiko; Tanaka, Ryojiro; Hamahira, Kiyoshi; Nakanishi, Koichi; Yoshikawa, Norishige; Matsuo, Masafumi

    2006-02-01

    Atypical membranoproliferative glomerulonephritis (MPGN) has been reported to have a good prognosis when treated with corticosteroids. However, this recommendation is based on uncontrolled trials and is associated with many complications. The purpose of our study is to determine whether steroid therapy is indicated for atypical MPGN. The cases of seven patients with atypical MPGN are reported in this study. Urinary abnormalities of five of them were detected by urine screening at school, of two because of macrohematuria. Hypocomplementemia was noted in six patients. All but one patient were treated without corticosteroids, and five with angiotensin-converting enzyme inhibitors (ACEI) and/or the Chinese herbal medicine Sairei-to (TJ-114). One patient recovered spontaneously from proteinuria and was therefore not treated, and one who developed severe proteinuria during observation was treated with corticosteroids. After an average follow-up period of 10.0 years, five patients showed normal urinary findings, one had hematuria and one proteinuria. At the most recent follow-up, the renal function of all patients remained within the normal range, and serum C3 had returned to normal levels in five out of six. These findings suggest that the indication of steroid therapy for atypical MPGN should be re-examined, since most of the patients with atypical MPGN seem to have an excellent prognosis without treatment with corticosteroids. PMID:16247645

  12. Volatile Organic Metabolites Identify Patients with Mesangial Proliferative Glomerulonephritis, IgA Nephropathy and Normal Controls

    PubMed Central

    Wang, Changsong; Feng, Yue; Wang, Mingao; Pi, Xin; Tong, Hongshuang; Wang, Yue; Zhu, Lin; Li, Enyou

    2015-01-01

    Urinary volatile organic compounds (VOCs) analysis for kidney diseases has attracted a large amount of scientific interest recently, and urinary metabolite analysis has already been applied to many diseases. Urine was collected from 15 mesangial proliferative glomerulonephritis (MsPGN) patients, 21 IgA nephropathy (IgAN) patients and 15 healthy controls. Solid phase microextraction–chromatography– mass spectrometry (SPME-GC-MS) was used to analyse the urinary metabolites. The statistical methods principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLSDA) were performed to process the final data. Five metabolites were significantly greater in the group of MsPGN patients than in the normal control group (P < 0.05) while three metabolites were found at increased levels in the group of IgAN patients compared with the normal controls (P < 0.05). In addition, five metabolites were significantly increased in the group of IgAN patients compared with the MsPGN patients (P < 0.05). These five metabolites may be specific biomarkers for distinguishing between MsPGN and IgAN. The analysis of urinary VOCs appears to have potential clinical applications as a diagnostic tool. PMID:26443483

  13. Volatile Organic Metabolites Identify Patients with Mesangial Proliferative Glomerulonephritis, IgA Nephropathy and Normal Controls.

    PubMed

    Wang, Changsong; Feng, Yue; Wang, Mingao; Pi, Xin; Tong, Hongshuang; Wang, Yue; Zhu, Lin; Li, Enyou

    2015-01-01

    Urinary volatile organic compounds (VOCs) analysis for kidney diseases has attracted a large amount of scientific interest recently, and urinary metabolite analysis has already been applied to many diseases. Urine was collected from 15 mesangial proliferative glomerulonephritis (MsPGN) patients, 21 IgA nephropathy (IgAN) patients and 15 healthy controls. Solid phase microextraction-chromatography- mass spectrometry (SPME-GC-MS) was used to analyse the urinary metabolites. The statistical methods principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLSDA) were performed to process the final data. Five metabolites were significantly greater in the group of MsPGN patients than in the normal control group (P < 0.05) while three metabolites were found at increased levels in the group of IgAN patients compared with the normal controls (P < 0.05). In addition, five metabolites were significantly increased in the group of IgAN patients compared with the MsPGN patients (P < 0.05). These five metabolites may be specific biomarkers for distinguishing between MsPGN and IgAN. The analysis of urinary VOCs appears to have potential clinical applications as a diagnostic tool. PMID:26443483

  14. Plasma and urine biochemical changes in cats with experimental immune complex glomerulonephritis.

    PubMed

    Bishop, S A; Lucke, V M; Stokes, C R; Gruffydd-Jones, T J

    1991-01-01

    Biochemical changes in plasma and urine were monitored in six cats before and during the induction of immune complex-mediated glomerulonephritis (ICGN) by daily intravenous administration of human serum albumin (HSA). The earliest indication of renal dysfunction in the cats was hypoalbuminaemia, which occurred as early as 13 weeks before cats developed clinical signs of renal disease. Proteinuria occurred 2 to 3 weeks before clinical disease, but was sensitive in predicting renal pathology in two cats that did not develop clinical signs of disease. In addition, increased activities of several urinary enzymes were detected in affected cats, with measurement of N-acetyl-beta-D-glucosaminidase and gamma-glutamyl transferase providing the earliest and most sensitive indication of renal damage. These plasma and urine measurements correlated more closely with the renal pathology, observed at postmortem, than clinical assessment of disease. It was concluded that ICGN in the cat could be diagnosed earliest by measurement of plasma protein concentration, whilst disease progress could be effectively monitored by including assays to measure urine protein and urine enzymes. PMID:1826913

  15. Differentiating Glomerular Inflammation from Fibrosis in A Bone Marrow Chimera for Rat Anti-GBM Glomerulonephritis

    PubMed Central

    Zhou, Cindy; Lou, Kristie; Tatum, Kiana; Funk, Jeremiah; Wu, Jean; Bartkowiak, Todd; Kagan, David; Lou, Yahuan

    2015-01-01

    Background Many types of glomerulonephritis (GN) undergo tandem connected phases: inflammation and fibrosis. Fibrosis in human GNs leads to irreversible end stage disease. This study investigated how these two phases were controlled. Methods Using a rat anti-glomerular basement membrane (GBM) GN model, we established bone marrow (BM) chimeras between GN-resistant Lewis (LEW) and GN-susceptible Wistar Kyoto (WKY) rats. Glomerular inflammation and fibrosis were compared between chimeras. Results LEW’s BM to WKY (WKYLEW) chimeras with or without co-transfer of host WKY’s T cells were GN-resistant. On the other hand, WKY’s BM to LEW (LEWWKY) chimeras developed glomerular inflammation and albuminuria upon immunization. Quantitative analysis showed that the number and composition of inflammatory cells in glomeruli of immunized LEWWKY chimeras were similar to those in immunized WKY rats at their inflammatory peak. Thus, glomerular inflammation was controlled by BM derived non-T cell populations. However, unlike WKY rats, LEWWKY rats did not develop fibrosis until the end of experiments (84 days) in spite of persistent inflammation and albuminuria. Conclusion Inflammation alone was not sufficient to trigger fibrosis, suggesting a critical role of glomerular cells in the fibrotic process. As LEWWKY chimera allows us to separate glomerular inflammation from fibrosis, this model provides a useful tool to study how fibrosis is initiated following inflammation. PMID:26337665

  16. Renal participation of myeloperoxidase in antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis.

    PubMed

    O'Sullivan, Kim M; Lo, Camden Y; Summers, Shaun A; Elgass, Kirstin D; McMillan, Paul J; Longano, Anthony; Ford, Sharon L; Gan, Poh-Yi; Kerr, Peter G; Kitching, A Richard; Holdsworth, Stephen R

    2015-11-01

    Myeloperoxidase (MPO) is an important neutrophil lysosomal enzyme, a major autoantigen, and a potential mediator of tissue injury in MPO-ANCA-associated vasculitis (MPO-AAV) and glomerulonephritis. Here we examined MPO deposition in kidney biopsies from 47 patients with MPO-AAV. Leukocyte accumulation and fibrin deposition consistent with cell-mediated immunity was a major feature. Tubulointerstitial macrophage, CD4+ and CD8+ T-cell, and neutrophil numbers correlated with low presenting eGFR. MPO was not detected in kidneys from patients with minimal change or thin basement membrane disease, but was prominent in glomerular, periglomerular, and tubulointerstitial regions in MPO-AAV. Extracellular MPO released from leukocytes was pronounced in all MPO-AAV patients. Similar numbers of neutrophils and macrophages expressed MPO in the kidneys, but colocalization studies identified neutrophils as the major source of extracellular MPO. Extraleukocyte MPO was prominent in neutrophil extracellular traps in the majority of patients; most of which had traps in half or more glomeruli. These traps were associated with more neutrophils and more MPO within glomeruli. Glomerular MPO-containing macrophages generated extracellular trap-like structures. MPO also localized to endothelial cells and podocytes. The presence of the most active glomerular lesions (both segmental necrosis and cellular crescents) correlated with intraglomerular CD4+ cells and MPO+ macrophages. Thus, cellular and extracellular MPO may cause glomerular and interstitial injury. PMID:26176828

  17. KDOQI US commentary on the 2012 KDIGO clinical practice guideline for glomerulonephritis.

    PubMed

    Beck, Laurence; Bomback, Andrew S; Choi, Michael J; Holzman, Larry B; Langford, Carol; Mariani, Laura H; Somers, Michael J; Trachtman, Howard; Waldman, Meryl

    2013-09-01

    Glomerulonephritis (GN) is an important cause of morbidity and mortality in patients of all ages throughout the world. Because these disorders are relatively rare, it is difficult to perform randomized clinical trials to define optimal treatment for many of the specific glomerulopathies. In the absence of high-grade evidence to guide the care of glomerular diseases, in June 2012, KDIGO (Kidney Disease: Improving Global Outcomes) published an international clinical guideline for GN. The Work Group report represents an important review of the literature in this area and offers valid and useful guidelines for the most common situations that arise in the management of patients with glomerular disease. This commentary, developed by a panel of clinical experts convened by the National Kidney Foundation, attempts to put the GN guideline into the context of the US health care system. Overall, we support the vast majority of the recommendations and highlight select areas in which epidemiological factors and medical practice patterns in this country justify modifications and adjustments in order to achieve favorable outcomes. There remain large gaps in our knowledge of the best approaches to treat glomerular disease and we strongly endorse an expanded clinical research effort to improve the health and long-term outcomes of children and adults with GN. PMID:23871408

  18. Membranoproliferative glomerulonephritis. A prospective clinical trial of platelet-inhibitor therapy

    SciTech Connect

    Donadio, J.V. Jr.; Anderson, C.F.; Mitchell, J.C.; Holley, K.E.; Ilstrup, D.M.; Fuster, V.; Chesebro, J.H.

    1984-05-31

    Forty patients with Type I membranoproliferative glomerulonephritis were treated for one year with dipyridamole, 225 mg per day, and aspirin, 975 mg per day, in a prospective, randomized, double-blind, placebo-controlled study. At the base line, the half-life of /sup 51/Cr-labeled platelets was reduced in 12 of 17 patients. The platelet half-life became longer and renal function stabilized in the treated group, as compared with the placebo group, suggesting a relation between platelet consumption and the glomerulopathy. The glomerular filtration rate, determined by iothalamate clearance, was better maintained in the treated group (average decrease, 1.3 ml per minute per 1.73 m/sup 2/ of body-surface area per 12 months) than in the placebo group (average decrease, 19.6). Fewer patients in the treated group than in the placebo group had progression to end-stage renal disease (3 of 21 after 62 months as compared with 9 of 19 after 33 months). The data suggest that dipyridamole and aspirin slowed the deterioration of renal function and the development of end-stage renal disease.

  19. Clinical and Immunologic Characteristics of Patients With ANCA-Associated Glomerulonephritis Combined With Membranous Nephropathy

    PubMed Central

    Zou, Rong; Liu, Gang; Cui, Zhao; Chen, Min; Zhao, Ming-Hui

    2015-01-01

    Abstract The concurrent antineutrophil cytoplasmic antibody-associated glomerulonephritis (ANCA-GN) and membranous nephropathy (MN) have been increasingly documented, mainly in case studies and case series; however, the differences of clinical and pathologic characteristics as well as outcomes between ANCA-GN patients with and without MN remain unclear. The current study investigated the clinical and immunologic features of patients with combined ANCA-GN and MN in a large cohort. Twenty-seven of 223 patients had combined ANCA-GN and MN; they had significantly higher levels of initial serum creatinine, higher Birmingham Vasculitis Activity Score and poorer renal outcome than ANCA-GN patients without MN (P < 0.05). ANCA-GN patients with MN could recognize the light chain of myeloperoxidase more frequently than those without MN (P < 0.05). The prevalence of circulating anti-PLA2R antibodies and glomerular PLA2R deposits was significantly lower in patients with combined ANCA-GN and MN than that in patients with idiopathic MN (P < 0.05). Compared with the idiopathic MN patients, the patients with combined ANCA-GN and MN had significantly higher recognition frequency of immunoglobulin (Ig) G2 and IgG3, and significantly lower recognition frequency of IgG4 (P < 0.05). Patients with combined ANCA-GN and MN had distinct clinical features and a different pathogenesis of MN. PMID:26376387

  20. Renal parenchymal resistance in patients with biopsy proven glomerulonephritis: Correlation with histological findings.

    PubMed

    Gigante, Antonietta; Barbano, Biagio; Di Mario, Francesca; Rosato, Edoardo; Simonelli, Marzia; Rocca, Anna Rachele; Conti, Fabrizio; Ceccarelli, Fulvia; Giannakakis, Konstantinos; Valesini, Guido; Cianci, Rosario

    2016-09-01

    Renal Doppler ultrasound is increasingly used in nephrology for the evaluation of renovascular disease, allograft dysfunction, and chronic nephropathies. We compared intrarenal hemodynamic parameters to biopsy findings of glomerular sclerosis, tubular atrophy, interstitial fibrosis, crescents, arteriolosclerosis, and clinical variables in 100 patients. A positive correlation exists between renal function and percentage of glomerular sclerosis (P <0.01, r = 0.26), conversely a negative correlation exists between glomerular filtrate rate and percentage of glomerular sclerosis(P <0.0001, r = -0.35). The percentage of glomerular sclerosis correlate positively with pulsatile index (PI) (P <0.05, r = 0.21) and renal resistive index (RI) (P <0.05, r = 0.20). The percentage of crescents correlates positively with PI(P <0.05, r = 0.21) and RI (P <0.05, r = 0.20). Classifying arteriolosclerosis in four groups according to a severity scale, from absence to severe, PI (P <0.05) and RI (P <0.01) were significantly different. In the post hoc analysis, the median values of PI and RI are significantly different in patients with severe arteriolosclerosis than others. Ultrasound examination is a non-invasive diagnostic technique used on patients with suspected or established renal disease. Our study shows a close correlation between kidney function, ultrasound parameters, and histological findings. Measurement of renal parenchymal resistance by ultrasound could be used in association with biopsy and glomerular function for the evaluation of renal damage in patients with glomerulonephritis. PMID:27091839

  1. The interstitial expression of alpha-smooth muscle actin in glomerulonephritis is associated with renal function

    PubMed Central

    Novakovic, Zana Saratlija; Durdov, Merica Glavina; Puljak, Livia; Saraga, Marijan; Ljutic, Dragan; Filipovic, Tomislav; Pastar, Zvonimir; Bendic, Antonia; Vukojevic, Katarina

    2012-01-01

    Summary Background In a healthy kidney, contractile protein alpha-smooth muscle actin (ASMA) is immunohistochemically strongly expressed only in the blood vessels, while in pathological conditions it can be visualized in glomerular mesangial cells and interstitial myofibroblasts. The aim of this study was to explore the possible correlation between expression of ASMA in glomerulonephritis (GN) and indicators of renal function. Material/Methods We analyzed expression of ASMA in percutaneous renal biopsy of 142 adult and pediatric patients with GN and its correlation with blood pressure, serum creatinine, creatinine clearance and 24-hour urine protein at the time of biopsy. Immunoexpression of ASMA was analyzed quantitatively using computer-assisted morphometric analysis. Relative surface of ASMA expression in all glomeruli and interstitium was calculated for each patient. Results In adults and children, greater expression of ASMA in interstitium was associated with higher serum creatinine and reduced creatinine clearance. Conversely, greater ASMA expression in glomeruli was associated with normal or decreased serum creatinine in adults and increased creatinine clearance in children. In children, correlation was found between high blood pressure and ASMA expression in interstitium. Conclusions We confirmed that interstitial expression of ASMA is associated with reduced renal function at time of biopsy. The connection of ASMA expression in glomeruli with lower serum creatinine and normal or increased creatinine clearance suggests a favorable role of this phenotypic change in glomerular filtration rate; further investigation is needed. PMID:22460095

  2. Recurrence of ANCA-negative renal-limited pauci-immune glomerulonephritis in the renal allograft

    PubMed Central

    Rajkumar, Venkatesh; Gowda, Kiran Krishne; Jha, Vivekanand; Kohli, Harbir Singh; Kumar, Vivek; Ramachandran, Raja

    2013-01-01

    Renal transplantation is the treatment of choice for end-stage renal disease (ESRD) due to pauci-immune crescentic glomerulonephritis (PICGN). A small subgroup of patients with PICGN are anti-neutrophil cytoplasmic antibody (ANCA) negative. We report a case of a patient with ANCA-negative renal-limited form of PICGN who developed ESRD despite treatment. He underwent live-related renal allograft transplantation after 12 months on haemodialysis. In the eighth post-transplant month, he developed graft dysfunction, which on evaluation turned out to be a graft recurrence of the basic disease in the form of PICGN. He received treatment with methylprednisolone, cyclophosphamide and plasmapheresis. However, his renal functions did not improve and he developed graft loss in the 11th post-transplant month and was started on continuous ambulatory peritoneal dialysis. We report a rare recurrence of renal-limited PICGN in the allograft. Patients with PICGN undergoing renal transplantation should be followed up carefully, and an early biopsy should be performed in the case of graft dysfunction to deal with this potentially graft-threatening complication. PMID:26064517

  3. CHARACTERIZATION OF A SAMPLE OF INTERMEDIATE-TYPE AGNs. I. SPECTROSCOPIC PROPERTIES AND SERENDIPITOUS DISCOVERY OF NEW DUAL AGNs

    SciTech Connect

    Benitez, Erika; Cruz-Gonzalez, Irene; Martinez, Benoni; Jimenez-Bailon, Elena; Mendez-Abreu, Jairo; Lopez-Martin, Luis; Fuentes-Carrera, Isaura; Leon-Tavares, Jonathan; Chavushyan, Vahram H.

    2013-01-20

    A sample of 10 nearby intermediate-type active galactic nuclei (AGNs) drawn from the Sloan Digital Sky Survey is presented. The aim of this work is to provide estimations of the black hole (BH) mass for the sample galaxies from the dynamics of the broad-line region. For this purpose, a detailed spectroscopic analysis of the objects was done. Using Baldwin-Phillips-Terlevich diagnostic diagrams, we have carefully classified the objects as true intermediate-type AGNs and found that 80%{sup +7.2%} {sub -17.3%} are composite AGNs. The BH mass estimated for the sample is within 6.54 {+-} 0.16 < log M {sub BH} < 7.81 {+-} 0.14. Profile analysis shows that five objects (J120655.63+501737.1, J121607.08+504930.0, J141238.14+391836.5, J143031.18+524225.8, and J162952.88+242638.3) have narrow double-peaked emission lines in both the red (H{alpha}, [N II] {lambda}{lambda}6548,6583 and [S II] {lambda}{lambda}6716, 6731) and the blue (H{beta} and [O III] {lambda}{lambda}4959, 5007) regions of the spectra, with velocity differences ({Delta}V) between the double peaks within 114 km s{sup -1} < {Delta}V < 256 km s{sup -1}. Two of them, J121607.08+504930.0 and J141238.14+391836.5, are candidates for dual AGNs since their double-peaked emission lines are dominated by AGN activity. In searches of dual AGNs, type 1, type II, and intermediate-type AGNs should be carefully separated, due to the high serendipitous number of narrow double-peaked sources (50% {+-} 14.4%) found in our sample.

  4. Kiloparsec-scale outflows are prevalent among luminous AGN: outflows and feedback in the context of the overall AGN population

    NASA Astrophysics Data System (ADS)

    Harrison, C. M.; Alexander, D. M.; Mullaney, J. R.; Swinbank, A. M.

    2014-07-01

    We present integral field unit observations covering the [O III]λλ4959, 5007 and Hβ emission lines of 16 z < 0.2 type 2 active galactic nuclei (AGN). Our targets are selected from a well-constrained parent sample of ≈24 000 AGN so that we can place our observations into the context of the overall AGN population. Our targets are radio quiet with star formation rates (SFRs; ≲[10-100] M⊙ yr-1) that are consistent with normal star-forming galaxies. We decouple the kinematics of galaxy dynamics and mergers from outflows. We find high-velocity ionized gas (velocity widths ≈600-1500 km s-1; maximum velocities ≤1700 km s-1) with observed spatial extents of ≳(6-16) kpc in all targets and observe signatures of spherical outflows and bi-polar superbubbles. We show that our targets are representative of z < 0.2, luminous (i.e. L[O III] > 1041.7 erg s-1) type 2 AGN and that ionized outflows are not only common but also in ≥70 per cent (3σ confidence) of cases, they are extended over kiloparsec scales. Our study demonstrates that galaxy-wide energetic outflows are not confined to the most extreme star-forming galaxies or radio-luminous AGN; however, there may be a higher incidence of the most extreme outflow velocities in quasars hosted in ultraluminous infrared galaxies. Both star formation and AGN activity appear to be energetically viable to drive the outflows and we find no definitive evidence that favours one process over the other. Although highly uncertain, we derive mass outflow rates (typically ≈10 times the SFRs), kinetic energies (≈0.5-10 per cent of LAGN) and momentum rates (typically ≳10-20 × LAGN/c) consistent with theoretical models that predict AGN-driven outflows play a significant role in shaping the evolution of galaxies.

  5. AGN host galaxy mass function in COSMOS. Is AGN feedback responsible for the mass-quenching of galaxies?

    NASA Astrophysics Data System (ADS)

    Bongiorno, A.; Schulze, A.; Merloni, A.; Zamorani, G.; Ilbert, O.; La Franca, F.; Peng, Y.; Piconcelli, E.; Mainieri, V.; Silverman, J. D.; Brusa, M.; Fiore, F.; Salvato, M.; Scoville, N.

    2016-04-01

    We investigate the role of supermassive black holes in the global context of galaxy evolution by measuring the host galaxy stellar mass function (HGMF) and the specific accretion rate, that is, λSAR, the distribution function (SARDF), up to z ~ 2.5 with ~1000 X-ray selected AGN from XMM-COSMOS. Using a maximum likelihood approach, we jointly fit the stellar mass function and specific accretion rate distribution function, with the X-ray luminosity function as an additional constraint. Our best-fit model characterizes the SARDF as a double power-law with mass-dependent but redshift-independent break, whose low λSAR slope flattens with increasing redshift while the normalization increases. This implies that for a given stellar mass, higher λSAR objects have a peak in their space density at earlier epoch than the lower λSAR objects, following and mimicking the well-known AGN cosmic downsizing as observed in the AGN luminosity function. The mass function of active galaxies is described by a Schechter function with an almost constant M∗⋆ and a low-mass slope α that flattens with redshift. Compared to the stellar mass function, we find that the HGMF has a similar shape and that up to log (M⋆/M⊙) ~ 11.5, the ratio of AGN host galaxies to star-forming galaxies is basically constant (~10%). Finally, the comparison of the AGN HGMF for different luminosity and specific accretion rate subclasses with a previously published phenomenological model prediction for the "transient" population, which are galaxies in the process of being mass-quenched, reveals that low-luminosity AGN do not appear to be able to contribute significantly to the quenching and that at least at high masses, that is, M⋆ > 1010.7 M⊙, feedback from luminous AGN (log Lbol ≳ 46 [erg/s]) may be responsible for the quenching of star formation in the host galaxy.

  6. AGN and Star Formation in HerMES-IRS sources

    NASA Astrophysics Data System (ADS)

    Feltre, Anna; Hatziminaoglou, Evanthia; Hernán-Caballero, Antonio; Fritz, Jacopo; Franceschini, Alberto

    2014-07-01

    One of the remaining open issues in the context of the analysis of Active Galactic Nuclei (AGN) is the evidence that nuclear gravitational accretion is often accompanied by a concurrent starburst activity. We developed a spectral energy distribution (SED) fitting technique to derive simultaneously the physical properties of active galaxies and coexisting starbursts making the best use of Spitzer and Herschel IR observations. We apply the SED fitting procedure to a large sample of extragalactic sources representing the HerMES (Herschel/Multi-tiered Extragalactic Survey) population with IRS spectra with a plethora of multi-wavelength data in order to study the impact of a possible presence of an AGN on the host galaxy's properties. We analyze the star formation rate (SFR) in conncetion to the presence of an AGN and compared the properties of the hot (AGN) and cold (starburst) dust component. Our findings are consistent with no evidence for the presence of an AGN affecting the star formation processes of the host galaxies.

  7. The New Spectral Picture of Seyfert 1 AGNs

    NASA Astrophysics Data System (ADS)

    Miyake, K.; Noda, H.; Yamada, S.; Makishima, K.

    2014-07-01

    X-ray spectra of active galactic nuclei (AGNs) were so far considered to consist of a single power-law (PL) like primary component and a reflection component accompanied by an FeKα line. However, the assumption of ``single primary component'' has not been confirmed observationally. To overcome this limitation, we developed a method that can decompose observed AGN spectra model-independently using time-variability (Noda et al. 2011, 2013). We applied it to the bright and variable Seyfert 1 AGN, IC4329A. It was observed by Suzaku 5 times in 2007, and once in 2012. Using our method, the time-averaged spectra have been successfully decomposed into a fast-variable component and a slowly-variable one. While the former can be regarded as a PL with photon index Γ~2.1, the latter is explained as a sum of the distant reflection component and a harder PL with Γ~1.4. This harder PL component, observed in all observations of IC 4329A and in many other AGNs (Noda et al. 2011, 2013), can be interpreted neither as partially-covered Γ~2.1 PL, nor relativistic reflection that varies with the primary. Therefore, the Γ~1.4 PL is considered to be another primary component. Its recognition has a big impact on our understanding of the AGN central engine.

  8. Inverse Compton X-ray signature of AGN feedback

    NASA Astrophysics Data System (ADS)

    Bourne, Martin A.; Nayakshin, Sergei

    2013-12-01

    Bright AGN frequently show ultrafast outflows (UFOs) with outflow velocities vout ˜ 0.1c. These outflows may be the source of AGN feedback on their host galaxies sought by galaxy formation modellers. The exact effect of the outflows on the ambient galaxy gas strongly depends on whether the shocked UFOs cool rapidly or not. This in turn depends on whether the shocked electrons share the same temperature as ions (one-temperature regime, 1T) or decouple (2T), as has been recently suggested. Here we calculate the inverse Compton spectrum emitted by such shocks, finding a broad feature potentially detectable either in mid-to-high energy X-rays (1T case) or only in the soft X-rays (2T). We argue that current observations of AGN do not seem to show evidence for the 1T component. The limits on the 2T emission are far weaker, and in fact it is possible that the observed soft X-ray excess of AGN is partially or fully due to the 2T shock emission. This suggests that UFOs are in the energy-driven regime outside the central few pc, and must pump considerable amounts of not only momentum but also energy into the ambient gas. We encourage X-ray observers to look for the inverse Compton components calculated here in order to constrain AGN feedback models further.

  9. A Meeting on the AGN/Galaxy Connection

    NASA Technical Reports Server (NTRS)

    Kinney, Anne

    1999-01-01

    This grant was used for travel support of several junior astronomers to attend the meeting "The Actice Galactic Nuclei (AGN)/Normal Galaxy Connection", Session El.2 of the 32nd COSPAR Assembly held in Nagoya, Japan, 12-19 July 1998. This meeting included the contributions from both theoretical and observational astronomers to the following fundamental questions: What causes the activity in galaxies? What is the difference between normal and active galaxies? Which processes are responsible for fueling the AGN? Do all galaxies have central Black Holes? What is the difference between low and high luminosity AGN? The observational papers discussed themes like: the detection of the black hole at the nucleus of our Galaxy, as well as in other galaxies; results from surveys of AGN in local galaxies, the source of their activity and their cold gas content; the observations of quasar host galaxies; the properties of Ultraluminous Infrared Galaxies. These papers used data from ground based observatories and several space missions (e.g. ASCA, ROSAT, HST, ISO) in wavebands from radio through gamma-rays. The theoretical papers discussed issues like: mechanisms to fuel the AGN; the physics of the accretion process; the formation of black-holes, quasars and their jets.

  10. The QUEST-La Silla AGN Variability Survey

    NASA Astrophysics Data System (ADS)

    Cartier, R.; Lira, P.; Coppi, P.; Sánchez, P.; Arévalo, P.; Bauer, F. E.; Muñoz, R. R.

    2016-03-01

    It is widely believed that supermassive black holes reside at the centres of every massive galaxy. When actively accreting they are known as Active Galactic Nuclei (AGNs). Most commonly, their presence is exposed by the radiation generated by the accretion of matter toward their centres. This radiation can show dramatic flux variations on timescales from minutes to years that can be observed across the full electromagnetic spectrum from X-ray to radio wavelengths. Although the exact origin of AGN variability remains unclear, such variability can be used as an efficient tool to find them and to understand the origin and demographics of flux variations. To this end, we have undertaken an AGN variability survey using the QUEST camera on the ESO 1.0-metre Schmidt Telescope at La Silla. The QUEST-La Silla AGN Variability Survey aims to discover thousands of new AGNs, and provide highly sampled light curves to study the ultraviolet/optical flux variations to a limiting magnitude of r ~ 21.5 mag.

  11. Coordinated Multifrequency Observations of Variable Agns

    NASA Astrophysics Data System (ADS)

    Worrall, Diana M.

    1984-07-01

    Our ME measurements of BL Lac objects to date, coordinated with observations in other frequency bands, show positive spectral curvature within the infrared to ultraviolet energy range (Worrall and Bruhweiler 1982). There is evidence that this component is synchrotron radiation. In order to fit the spectral measurements, we find that relativistic beaming is an essential ingredient of simple models not involving electron reacceleration. It is important to discover to what extent this is observationally true of all BL Lac objects, and to then compare with expectations of the distribution in Lorentz factor derived from geometrical arguments. Our sample of BL Lac objects so far numbers 5. There are 17 other BL Lac objects for which IUE observations are listed in the master catalogue. However, many of these objects are so heavily contaminated by a galactic component in the visual and near infrared that the data cannot be usefully employed for our purpose. Also, to our knowledge, the necessary nearly simultaneous coverage in the infrared and visual only exists for 6 of these 17. The near-simultaneity is a vital element, since these active galactic nuclei (AGNs) tend to exhibit different flux variability characteristics in the different available wavebands. We present a target list primarily composed of BL Lac objects, but including 3 QSOs. Conclusions from non-simultaneous multifrequency observations by Malkan and Sargent (1982) suggest that one difference between QSOs and BL Lacs is that the non-thermal infrared to ultraviolet QSO flux does not appear to exhibit curvature. We would like to investigate this more closely, with simultaneous observations. We propose to coordinate all our observations with radio, millimeter, infrared and visual wavelength coverage and have calculated time periods during which this will be possible. Final target selection from our list of visually variable objects will be based on their magnitudes just prior to shift allotment.

  12. Agnes Pockels: Life, Letters and Papers

    NASA Astrophysics Data System (ADS)

    Helm, Christiane A.

    2004-03-01

    Agnes Pockels (1862 - 1935) was a German woman, whose studies pioneered surface science. She was born in malaria infected North Italy while her father served in the Austrian army. Because he suffered adverse health effects, the family moved in1871 to Braunschweig (North Germany). There, Pockels went to high school. She was interested in science, but formal training was not available for girls. She took on the role of household manager and nurse as her parents' health deteriorated further. Her diary illustrates the difficulties she faced in trying to maintain her own health, the health of her parents and her scientific research at the same time. When Pockels was 18 or 19, she designed a ring tensiometer. Additionally, she found a new method to introduce water-insoluble compounds to the water surface by dissolving them in an organic solvent, and applying drops of the solution. Her surface film balance technique from 1882 is the basis for the method later developed by Langmuir. Since her experimental work was highly original and in a new field, she failed to get it recognized in her own country. When she was 28, she wrote to Lord Rayleigh, since she had read about his recent experiments in surface physics. Rayleigh was so impressed with her experimental methods and results that he had her letter translated from German and published it in Nature (1891). She continued her research on surface films, interactions of solutions and contact angles (more papers, 3 in Nature). Still, she did all experiments at home. With the death of her brother in 1913 and the onset of the war, she retired into private life. Thus she was surprised when she was awarded in her late 60ies with a honorary doctorate by the TU Braunschweig (1932) and the annual prize of the German Colloid Society (1931).

  13. Compton thick AGN in the XMM-COSMOS survey

    NASA Astrophysics Data System (ADS)

    Lanzuisi, G.; Ranalli, P.; Georgantopoulos, I.; Georgakakis, A.; Delvecchio, I.; Akylas, T.; Berta, S.; Bongiorno, A.; Brusa, M.; Cappelluti, N.; Civano, F.; Comastri, A.; Gilli, R.; Gruppioni, C.; Hasinger, G.; Iwasawa, K.; Koekemoer, A.; Lusso, E.; Marchesi, S.; Mainieri, V.; Merloni, A.; Mignoli, M.; Piconcelli, E.; Pozzi, F.; Rosario, D. J.; Salvato, M.; Silverman, J.; Trakhtenbrot, B.; Vignali, C.; Zamorani, G.

    2015-01-01

    Heavily obscured, Compton thick (CT, NH> 1024 cm-2) active galactic nuclei (AGN) may represent an important phase in AGN/galaxy co-evolution and are expected to provide a significant contribution to the cosmic X-ray background at its peak. However, unambiguously identifying CT AGN beyond the local Universe is a challenging task even in the deepest X-ray surveys, and given the expected low spatial density of these sources in the 2-10 keV band, large area surveys are needed to collect sizable samples. Through direct X-ray spectra analysis, we selected 39 heavily obscured AGN (NH>3 × 1023 cm-2) at bright X-ray fluxes (F2-10 ≳ 10-14 erg s-1 cm-2) in the 2 deg2 XMM-COSMOS survey. After selecting CT AGN based on the fit of a simple absorbed two power law model to the shallow XMM-Newton data, the presence of bona fide CT AGN was confirmed in 80% of the sources using deeper Chandra data and more complex models. The final sample comprises ten CT AGN (six of them also have a detected Fe Kα line with EW ~ 1 keV), spanning a wide range of redshifts (z ~ 0.1-2.5) and luminosity (L2-10 ~ 1043.5-1045 erg s-1) and is complemented by 29 heavily obscured AGN spanning the same redshift and luminosity range. We collected the rich multi-wavelength information available for all these sources, in order to study the distribution of super massive black hole and host properties, such as black hole mass (MBH), Eddington ratio (λEdd), stellar mass (M∗), specific star formation rate (sSFR) in comparison with a sample of unobscured AGN. We find that highly obscured sources tend to have significantly smaller MBH and higher λEdd with respect to unobscured sources, while a weaker evolution in M∗ is observed. The sSFR of highly obscured sources is consistent with the one observed in the main sequence of star forming galaxies, at all redshifts. We also present and briefly discuss optical spectra, broadband spectral energy distribution (SED) and morphology for the sample of ten CT AGN. Both

  14. The Triggering and Evolution of AGN in Cluster Fields

    NASA Astrophysics Data System (ADS)

    Allen, Steven

    It is now well established that the evolution of super-massive black holes (SMBHs) is closely linked to that of their host galaxies. However, the detailed causal connections behind this relationship remain largely unknown. This is due in part to the complex diversity of active galactic nuclei (AGN) properties, the differing time-scales for AGN and star-forming processes, and a variety of observational selection effects. Physically, a prerequisite for both AGN activity and the formation of new stars in the host galaxy is the availability of gas. Environmental processes in galaxy clusters can strongly and rapidly affect gas reservoirs. Observations of star-forming galaxies in clusters have shown that the cluster environment drives evolution at a different rate than in the field. We here propose to make new measurements of the distribution of X-ray selected AGN, within cluster fields, and of their infrared (IR) and ultra-violet (UV) host galaxy properties to better understand the AGN triggering process, and the physical links between the SMBHs and their host galaxies. With a combination of superb spatial resolution and excellent sensitivity, Chandra X-ray observations have revolutionised studies of AGN evolution. The X-ray waveband is optimally suited for AGN surveys suffering little contamination from the host galaxy and only modest absorption bias, down to luminosities of 10^43 erg/s and across a wide range of source redshifts, providing direct access to a significant fraction of the total accretion power in the Universe (Brandt & Alexander 2015). However, two significant challenges exist that limit current studies of X-ray AGN in clusters: 1) the expense of optical follow-up of X-ray point source targets in order to confirm cluster membership; and 2) the low number of X-ray AGN that reside in clusters (typically 2-3 per cluster) relative to the background population (9,800 deg^2 in the deepest Chandra fields). In Ehlert et al. (2013, 2014 and 2015) we presented a

  15. MERGING AND CLUSTERING OF THE SWIFT BAT AGN SAMPLE

    SciTech Connect

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa

    2010-06-20

    We discuss the merger rate, close galaxy environment, and clustering on scales up to an Mpc of the Swift BAT hard X-ray sample of nearby (z<0.05), moderate-luminosity active galactic nuclei (AGNs). We find a higher incidence of galaxies with signs of disruption compared to a matched control sample (18% versus 1%) and of close pairs within 30 kpc (24% versus 1%). We also find a larger fraction with companions compared to normal galaxies and optical emission line selected AGNs at scales up to 250 kpc. We hypothesize that these merging AGNs may not be identified using optical emission line diagnostics because of optical extinction and dilution by star formation. In support of this hypothesis, in merging systems we find a higher hard X-ray to [O III] flux ratio, as well as emission line diagnostics characteristic of composite or star-forming galaxies, and a larger IRAS 60 {mu}m to stellar mass ratio.

  16. Quenching histories of galaxies and the role of AGN feedback

    NASA Astrophysics Data System (ADS)

    Smethurst, Rebecca Jane; Lintott, Chris; Simmons, Brooke; Galaxy Zoo Team

    2016-01-01

    Two open issues in modern astrophysics are: (i) how do galaxies fully quench their star formation and (ii) how is this affected - or not - by AGN feedback? I present the results of a new Bayesian-MCMC analysis of the star formation histories of over 126,000 galaxies across the colour magnitude diagram showing that diverse quenching mechanisms are instrumental in the formation of the present day red sequence. Using classifications from Galaxy Zoo we show that the rate at which quenching can occur is morphologically dependent in each of the blue cloud, green valley and red sequence. We discuss the nature of these possible quenching mechanisms, considering the influence of secular evolution, galaxy interactions and mergers, both with and without black hole activity. We focus particularly on the relationship between these quenched star formation histories and the presence of an AGN by using this new Bayesian method to show a population of type 2 AGN host galaxies have recently (within 2 Gyr) undergone a rapid (τ < 1 Gyr) drop in their star formation rate. With this result we therefore present the first statistically supported observational evidence that AGN feedback is an important mechanism for the cessation of star formation in this population of galaxies. The diversity of this new method also highlights that such rapid quenching histories cannot account fully for all the quenching across the current AGN host population. We demonstrate that slower (τ > 2 Gyr) quenching rates dominate for high stellar mass (log10[M*/M⊙] > 10.75) hosts of AGN with both early- and late-type morphology. We discuss how these results show that both merger-driven and non-merger processes are contributing to the co-evolution of galaxies and supermassive black holes across the entirety of the colour magnitude diagram.

  17. Tracing outflows in the AGN forbidden region with SINFONI

    NASA Astrophysics Data System (ADS)

    Kakkad, D.; Mainieri, V.; Padovani, P.; Cresci, G.; Husemann, B.; Carniani, S.; Brusa, M.; Lamastra, A.; Lanzuisi, G.; Piconcelli, E.; Schramm, M.

    2016-08-01

    Context. Active galactic nucleus (AGN) driven outflows are invoked in numerical simulations to reproduce several observed properties of local galaxies. The z > 1 epoch is of particular interest as it was during this time that the volume averaged star formation and the accretion rate of black holes were at their maximum. Radiatively driven outflows are therefore believed to be common during this epoch. Aims: We aim to trace and characterize outflows in AGN hosts with high mass accretion rates at z > 1 using integral field spectroscopy. We obtain spatially resolved kinematics of the [O iii] λ5007 line in two targets which reveal the morphology and spatial extension of the outflows. Methods: We present SINFONI observations in the J band and the H + K band of five AGNs at 1.2 < z < 2.2. To maximize the chance of observing radiatively driven outflows, our sample was pre-selected based on peculiar values of the Eddington ratio and the hydrogen column density of the surrounding interstellar medium. We observe high velocity (~600-1900 km s-1) and kiloparsec scale extended ionized outflows in at least three of our targets, using [O iii] λ5007 line kinematics tracing the AGN narrow line region. We estimate the total mass of the outflow, the mass outflow rate, and the kinetic power of the outflows based on theoretical models and report on the uncertainties associated with them. Results: We find mass outflow rates of ~1-10 M⊙/yr for the sample presented in this paper. Based on the high star formation rates of the host galaxies, the observed outflow kinetic power, and the expected power due to the AGN, we infer that both star formation and AGN radiation could be the dominant source for the outflows. The outflow models suffer from large uncertainties, hence we call for further detailed observations for an accurate determination of the outflow properties to confirm the exact source of these outflows.

  18. The INTEGRAL/IBIS AGN catalogue: an update

    NASA Astrophysics Data System (ADS)

    Malizia, A.; Landi, R.; Molina, M.; Bassani, L.; Bazzano, A.; Bird, A. J.; Ubertini, P.

    2016-04-01

    In the most recent IBIS survey based on observations performed during the first 1000 orbits of INTEGRAL, are listed 363 high energy emitters firmly associated with AGN, 107 of which are reported here for the first time. We have used X-ray data to image the IBIS 90% error circle of all the AGN in the sample of 107, in order to obtain the correct X-ray counterparts, locate them with arcsec accuracy and therefore pinpoint the correct optical counterparts. This procedure has led to the optical and spectral characterization of the entire sample. This new set consists of 34 broad line or type 1 AGN, 47 narrow line or type 2 AGN, 18 Blazars and 8 sources of unknown class. These 8 sources have been associated with AGN from their positional coincidence with 2MASX/Radio/X-ray sources. Seven high energy emitters have been included since they are considered to be good AGN candidates. Spectral analysis has been already performed on 55 objects and the results from the most recent and/or best statistical measurements have been collected. For the remaining 52 sources, we report the spectral analysis for the first time in this work. We have been able to obtain the full X-ray coverage of the sample making use of data from Swift/XRT, XMM-Newton and NuSTAR. In addition to the spectral characterization of the entire sample, this analysis has enabled us to identify peculiar sources and by comparing different datasets, highlight flux variability in the 2-10 keV and 20-40 keV bands.

  19. The most obscured AGN in the COSMOS field

    NASA Astrophysics Data System (ADS)

    Lanzuisi, G.; Perna, M.; Delvecchio, I.; Berta, S.; Brusa, M.; Cappelluti, N.; Comastri, A.; Gilli, R.; Gruppioni, C.; Mignoli, M.; Pozzi, F.; Vietri, G.; Vignali, C.; Zamorani, G.

    2015-06-01

    Highly obscured active galactic nuclei (AGN) are common in nearby galaxies, but are difficult to observe beyond the local Universe, where they are expected to significantly contribute to the black hole accretion rate density. Furthermore, Compton-thick (CT) absorbers (NH ≳ 1024 cm-2) suppress even the hard X-ray (2-10 keV) AGN nuclear emission, and therefore the column density distribution above 1024 cm-2 is largely unknown. We present the identification and multi-wavelength properties of a heavily obscured (NH ≳ 1025 cm-2), intrinsically luminous (L2-10 > 1044 erg s-1) AGN at z = 0.353 in the COSMOS field. Several independent indicators, such as the shape of the X-ray spectrum, the decomposition of the spectral energy distribution and X-ray/[NeV] and X-ray/6 μm luminosity ratios, agree on the fact that the nuclear emission must be suppressed by a ≳1025 cm-2 column density. The host galaxy properties show that this highly obscured AGN is hosted in a massive star-forming galaxy, showing a barred morphology, which is known to correlate with the presence of CT absorbers. Finally, asymmetric and blueshifted components in several optical high-ionization emission lines indicate the presence of a galactic outflow, possibly driven by the intense AGN activity (LBol/LEdd = 0.3-0.5). Such highly obscured, highly accreting AGN are intrinsically very rare at low redshift, whereas they are expected to be much more common at the peak of the star formation and BH accretion history, at z ~ 2-3. We demonstrate that a fully multi-wavelength approach can recover a sizable sample of such peculiar sources in large and deep surveys such as COSMOS.

  20. The INTEGRAL/IBIS AGN catalogue: an update

    NASA Astrophysics Data System (ADS)

    Malizia, A.; Landi, R.; Molina, M.; Bassani, L.; Bazzano, A.; Bird, A. J.; Ubertini, P.

    2016-07-01

    In the most recent IBIS survey based on observations performed during the first 1000 orbits of INTEGRAL, are listed 363 high-energy emitters firmly associated with AGN, 107 of which are reported here for the first time. We have used X-ray data to image the IBIS 90 per cent error circle of all the AGN in the sample of 107, in order to obtain the correct X-ray counterparts, locate them with arcsec accuracy and therefore pinpoint the correct optical counterparts. This procedure has led to the optical and spectral characterization of the entire sample. This new set consists of 34 broad line or type 1 AGN, 47 narrow line or type 2 AGN, 18 blazars and 8 sources of unknown class. These eight sources have been associated with AGN from their positional coincidence with 2MASX/Radio/X-ray sources. Seven high-energy emitters have been included since they are considered to be good AGN candidates. Spectral analysis has been already performed on 55 objects and the results from the most recent and/or best statistical measurements have been collected. For the remaining 52 sources, we report the spectral analysis for the first time in this work. We have been able to obtain the full X-ray coverage of the sample making use of data from Swift/XRT, XMM-Newton and NuSTAR. In addition to the spectral characterization of the entire sample, this analysis has enabled us to identify peculiar sources and by comparing different data sets, highlight flux variability in the 2-10 keV and 20-40 keV bands.

  1. The merging/AGN connection: a case for 3D spectroscopy

    NASA Astrophysics Data System (ADS)

    Sánchez, S. F.; Christensen, L.; Becker, T.; Kelz, A.; Jahnke, K.; Benn, C. R.; García-Lorenzo, B.; Roth, M. M.

    2004-02-01

    We discuss an ongoing study of the connection between galaxy merging/interaction and AGN activity, based on integral field spectroscopy. We focus on the search for AGN ionization in the central regions of mergers, previously not classified as AGNs. We present here the science case, the current status of the project, and plans for future observations.

  2. Soft X-Ray Spectra of AGN Discovered Via Their Hard X-Ray

    NASA Technical Reports Server (NTRS)

    Schwartz, Daniel

    1998-01-01

    This final report is a study of the Active Galactic Nuclei (AGN). Investigation of the soft x-ray spectra of AGN were performed by using their hard x-ray emission. ROSAT observations of AGN was also performed, which allowed for the study of these x-ray spectra and the structures of 7 clusters of galaxies.

  3. On the electron-positron cascade in AGN central engines

    NASA Astrophysics Data System (ADS)

    Ford, Alex; Keenan, Brett; Medvedev, Mikhail

    2016-03-01

    Processes around spinning supermassive black holes (BH) in active galactic nuclei (AGN) are believed to determine how relativistic jets are launched and how the BH energy is extracted. The key ``ingredient'' is the origin of plasma in BH magnetospheres. In order to explore the process of the electron-positron plasma production, we developed a numerical code which models a one-dimensional (along a magnetic field line) dynamics of the cascade. Our simulations show that plasma production is controlled by the spectrum of the ambient photon field, the B-field strength, the BH spin and mass. Implications of our results to the Galactic Center and AGNs are discussed.

  4. The QUEST-La Silla AGN Variability Survey

    NASA Astrophysics Data System (ADS)

    Cartier, Régis; Lira, Paulina; Coppi, Paolo; Sánchez, Paula; Arévalo, Patricia; Bauer, Franz E.; Rabinowitz, David; Zinn, Robert; Muñoz, Ricardo R.; Meza, Nicolás

    2015-09-01

    We present the characterization and initial results from the QUEST-La Silla active galactic nucleus (AGN) variability survey. This is an effort to obtain well-sampled optical light curves in extragalactic fields with unique multiwavelength observations. We present photometry obtained from 2010 to 2012 in the XMM-COSMOS field, which was observed over 150 nights using the QUEST camera on the European Southern Observatory (ESO) Schmidt telescope. The survey uses a broadband filter, the Q band, similar to the union of the g and the r filters, achieving an intrinsic photometric dispersion of 0.05 mag and a systematic error of 0.05 mag in the zero point. Since some detectors of the camera show significant nonlinearity, we use a linear correlation to fit the zero points as a function of the instrumental magnitudes, thus obtaining a good correction to the nonlinear behavior of these detectors. We obtain good photometry to an equivalent limiting magnitude of r˜ 20.5. The astrometry has an internal precision of ˜ 0\\buildrel{\\prime\\prime}\\over{.} 1 and an overall accuracy of 0\\buildrel{\\prime\\prime}\\over{.} 2 when compared to the Sloan Digital Sky Survey. Studying the optical variability of X-ray-detected sources in the XMM-COSMOS field, we find that the survey is ˜75%-80% complete to magnitudes r˜ 20, and ˜67% complete to a magnitude r˜ 21. Additionally, broad-line (BL) AGNs have larger variation amplitude than non-broad-line (NL) AGNs, with ˜80% of the BL AGNs classified as variable, while only ˜21% of the NL AGNs are classified as variable. We also find that ˜22% of objects classified as galaxies (GALs) are also variable. The determination and parameterization of the structure function ({{SF}}{norm}(τ )=A{τ }γ ) of the variable sources show that most BL AGNs are characterized by A\\gt 0.1 and γ \\gt 0.025. It is further shown that NL AGNs and GAL sources occupying the same parameter space in A and γ are very likely to correspond to obscured or low

  5. Antibody response and antibody affinity maturation in cats with experimental proliferative immune complex glomerulonephritis.

    PubMed

    Bishop, S A; Bailey, M; Lucke, V M; Stokes, C R

    1992-07-01

    An experimental model of proliferative glomerulonephritis (GN) in the cat, which closely resembles human proliferative forms of GN, has been used to study the role of antibody and antibody affinity in the development of immune complex-mediated renal disease. The serum IgG and IgM antibody response to antigen, average antibody affinity (avidity) and affinity heterogeneity of the IgG and IgM populations was assessed at varying times after commencement of chronic immunization with the antigen, human serum albumin (HSA), by enzyme immunoassay. Cats could be classified according to whether they were "low", "intermediate" or "high" IgG responders, by quantification of serum IgG values. Cats with the lowest serum IgG values failed to develop glomerulonephritis. However, there was no relationship between actual IgG values and the severity of the induced disease. In contrast to IgG, there was no division of cats into low or high IgM anti-HSA responders. Again, cats with the lowest IgM values failed to develop GN, but, more interestingly, a late, marked increase in serum IgM anti-HSA occurred only in cats that developed clinical signs of GN (anterior uveitis and nephrotic syndrome). Maturation of average, functional IgG affinity (avidity) for HSA following chronic immunization was clearly demonstrated for all cats. At the end of the experiment, all cats had IgG of high affinity for HSA and the average affinity heterogeneity of the IgG populations was less than in measurements taken earlier. Values of IgG affinity at the end of the experiment were very similar both in cats which developed GN and in those which remained clinically, biochemically and pathologically normal. In contrast to IgG antibody, some cats developed IgM of increased affinity, whilst others produced antibody of reduced affinity, following chronic immunization. There was no correlation between the development of disease and the production of either low or high affinity IgM antibody. Data indicated that an

  6. Antibody-mediated glomerulonephritis in mice: the role of endotoxin, complement and genetic background

    PubMed Central

    ROBSON, M G; COOK, H T; PUSEY, C D; WALPORT, M J; DAVIES, K A

    2003-01-01

    Antibody-mediated glomerulonephritis in man may be exacerbated by infection and this effect may be mediated by bacterial endotoxin. There is evidence supporting a role for endotoxin in heterologous nephrotoxic nephritis in rats, but the role of endotoxin in this model in mice has not previously been explored. Previous data in mice on the role of complement in this model are conflicting and this may be due to the mixed genetic background of mice used in these studies. We used the model of heterologous nephrotoxic nephritis in mice and explored the role of endotoxin, complement and genetic background. In this study we show a synergy between antibody and endotoxin in causing a neutrophil influx. We also show that C1q-deficient mice have an increased susceptibility to glomerular inflammation but this is seen only on a mixed 129/Sv × C57BL/6 genetic background. On a C57BL/6 background we did not find any differences in disease susceptibility when wildtype, C1q, factor B or factor B/C2 deficient mice were compared. We also demonstrate that C57BL/6 mice are more susceptible to glomerular inflammation than 129/Sv mice. These results show that endotoxin is required in this model in mice, and that complement does not play a major role in glomerular inflammation in C57BL/6 mice. C1q may play a protective role in mixed-strain 129/Sv × C57BL/6 mice, but the data may also be explained by systematic bias in background genes, as there is a large difference in disease susceptibility between C57BL/6 and 129/Sv mice. PMID:12930357

  7. Cocaine/levamisole-induced systemic vasculitis with retiform purpura and pauci-immune glomerulonephritis

    PubMed Central

    Veronese, F.V.; Dode, R.S.O.; Friderichs, M.; Thomé, G.G.; da Silva, D.R.; Schaefer, P.G.; Sebben, V.C.; Nicolella, A.R.; Barros, E.J.G.

    2016-01-01

    Levamisole has been increasingly used as an adulterant of cocaine in recent years, emerging as a public health challenge worldwide. Levamisole-associated toxicity manifests clinically as a systemic vasculitis, consisting of cutaneous, hematological, and renal lesions, among others. Purpura retiform, cutaneous necrosis, intravascular thrombosis, neutropenia, and less commonly crescentic nephritis have been described in association with anti-neutrophil cytoplasmic antibodies (ANCAs) and other autoantibodies. Here we report the case of a 49-year-old male who was a chronic cocaine user, and who presented spontaneous weight loss, arthralgia, and 3 weeks before admission purpuric skin lesions in the earlobes and in the anterior thighs. His laboratory tests on admission showed serum creatinine of 4.56 mg/dL, white blood count 3,800/μL, hemoglobin 7.3 g/dL, urinalysis with 51 white blood cells/μL and 960 red blood cells/μL, and urine protein-to-creatinine ratio 1.20. Serum ANCA testing was positive (>1:320), as well as serum anti-myeloperoxidase and anti-proteinase 3 antibodies. Urine toxicology screen was positive for cocaine and levamisole, with 62.8% of cocaine, 32.2% of levamisole, and 5% of an unidentified substance. Skin and renal biopsies were diagnostic for leukocytoclastic vasculitis and pauci-immune crescentic glomerulonephritis, respectively. The patient showed a good clinical response to cocaine abstinence, and use of corticosteroids and intravenous cyclophosphamide. Last serum creatinine was 1.97 mg/dL, white blood cell count 7,420/μL, and hemoglobin level 10.8 g/dL. In levamisole-induced systemic vasculitis, the early institution of cocaine abstinence, concomitant with the use of immunosuppressive drugs in severe cases, may prevent permanent end organ damage and associate with better clinical outcomes. PMID:27119429

  8. Association of Retinoid X Receptor Alpha Gene Polymorphism with Clinical Course of Chronic Glomerulonephritis.

    PubMed

    Grzegorzewska, Alicja E; Ostromecki, Grzegorz; Zielińska, Paulina; Mostowska, Adrianna; Niemir, Zofia; Polcyn-Adamczak, Magdalena; Pawlik, Magdalena; Sowińska, Anna; Jagodziński, Paweł P

    2015-01-01

    BACKGROUND Vitamin D (VD), VD binding protein, VD receptor (VDR), and retinoids are involved in pathogenesis of chronic glomerulonephritis (ChGN). We aimed to compare distribution of VD pathway gene polymorphisms in ChGN patients showing glomerular filtration rate (GFR) category 1-3, GFR category 5D, and healthy controls in order to elucidate the role of VD-related polymorphisms in the course of ChGN. MATERIAL AND METHODS GFR category 1-3 ChGN patients (n=195), GFR category 5D ChGN patients (n=178), and controls (n=751) underwent testing for polymorphisms of genes encoding VD binding protein (GC, rs2298849, rs7041, rs1155563), VDR (VDR, rs2228570, rs1544410), and retinoid X receptor alpha (RXRA, rs10776909, rs10881578, rs749759). RESULTS Among GFR 1-3 subjects possessing TT genotype of RXRA rs10776909, 75% of patients had nephrotic syndrome, and 37.5% had glomerular hyperfiltration defined as GFR >140 ml/min/1.73 m2, and, consequently, serum creatinine was lower in these patients compared to the remaining subjects (0.67±0.26 vs. 0.94±0.34, P=0.014). In GFR category 5D ChGN patients, frequencies of RXRA rs10776909 allele T (25% vs. 19%) and CT+TT (46% vs. 34%) were higher compared to frequencies of respective variants in controls (Ptrend=0.004, Pgenotype=0.008). CONCLUSIONS RXRA rs10776909 allele T is specifically involved in the pathogenesis of ChGN. This risk allele may be also associated with worse clinical course of ChGN. PMID:26610845

  9. Proliferative glomerulonephritis with monoclonal immunoglobulin G deposits complicated by immunoglobulin A nephropathy in the renal allograft.

    PubMed

    Sawada, Anri; Kawanishi, Kunio; Horita, Shigeru; Koike, Junki; Honda, Kazuho; Ochi, Ayami; Komoda, Mizuki; Tanaka, Yoichiro; Unagami, Kohei; Okumi, Masayoshi; Shimizu, Tomokazu; Ishida, Hideki; Tanabe, Kazunari; Nagashima, Yoji; Nitta, Kosaku

    2016-07-01

    Immunoglobulin (Ig) A nephropathy (IgAN) is a known autoimmune disease due to abnormal glycosylation of IgA1, and occasionally, IgG co-deposition occurs. The prognosis of IgG co-deposition with IgAN is adverse, as shown in the previous studies. However, in the clinical setting, monoclonality of IgG co-deposition with IgAN has not been observed. We describe a case of proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) combined with IgAN in a renal allograft. A-21-year-old man developed end-stage renal failure with unknown aetiology and underwent living-donor kidney transplantation from his mother 2 years after being diagnosed. One year after kidney transplantation, proteinuria 2+ and haematuria 2+ were detected; allograft biopsy revealed mesangial IgA and C3 deposits, indicating a diagnosis of IgAN. After tonsillectomy and steroid pulse therapy, proteinuria and haematuria resolved. However, 4 years after transplantation, pedal oedema, proteinuria (6.89 g/day) and allograft dysfunction (serum creatinine (sCr) 203.3 µmol/L) appeared. A second allograft biopsy showed mesangial expansion and focal segmental proliferative endocapillary lesions with IgA1λ and monoclonal IgG1κ depositions. Electron microscopic analysis revealed a massive amount of deposits, located in the mesangial and subendothelial lesions. A diagnosis of PGNMID complicated with IgAN was made, and rituximab and plasmapheresis were added to steroid pulse therapy. With this treatment, proteinuria was alleviated to 0.5 g/day, and the allograft dysfunction recovered to sCr 132.6 µmol/L. This case suggests a necessity for investigation of PGNMID and IgA nephropathy in renal allografts to detect monoclonal Ig deposition disease. PMID:26971743

  10. A Case of Fibrillary Glomerulonephritis Associated with Thrombotic Microangiopathy and Anti-Glomerular Basement Membrane Antibody

    PubMed Central

    Momose, Akishi; Nakajima, Taku; Chiba, Shigetoshi; Kumakawa, Kenjirou; Shiraiwa, Yasuo; Sasaki, Nobuhiro; Watanabe, Kazuo; Kitano, Etsuko; Hatanaka, Mitiyo; Kitamura, Hajime

    2015-01-01

    We present the first report of a case of fibrillary glomerulonephritis (FGN) associated with thrombotic microangiopathy (TMA) and anti-glomerular basement membrane antibody (anti-GBM antibody). A 54-year-old man was admitted to our hospital for high fever and anuria. On the first hospital day, we initiated hemodialysis for renal dysfunction. Laboratory data revealed normocytic-normochromic anemia with schistocytes in the peripheral smear, thrombocytopenia, increased serum lactate dehydrogenase, decreased serum haptoglobin, and negative results for both direct and indirect Coombs tests. Based on these results, we diagnosed TMA. Assays conducted several days later indicated a disintegrin-like and metalloprotease with a thrombospondin motif 13 (ADAMTS13) activity of 31.6%, and ADAMTS13 inhibitors were negative. We started plasma exchange using fresh frozen plasma and steroid pulse therapy. Anti-GBM antibody was found to be positive. Renal biopsy showed FGN. Blood pressure rose on the 46th hospital day, and mild convulsions developed. Based on magnetic resonance imaging of the head, the patient was diagnosed with reversible posterior leukoencephalopathy syndrome. Hypertension persisted despite administration of multiple antihypertensive agents, and the patient experienced a sudden generalized seizure. Computed tomography of the head showed multiple cerebral hemorrhages. However, his blood pressure subsequently decreased and the platelet count increased. TMA remitted following 36 plasma exchange sessions, but renal function was not restored, and maintenance hemodialysis was continued. The patient was discharged on the 119th day of hospitalization. In conclusion, it was shown that TMA, FGN and anti-GBM antibody were closely related. PMID:25873933

  11. Embryonic fibronectin isoforms are synthesized in crescents in experimental autoimmune glomerulonephritis.

    PubMed Central

    Nickeleit, V.; Zagachin, L.; Nishikawa, K.; Peters, J. H.; Hynes, R. O.; Colvin, R. B.

    1995-01-01

    Crescents are a severe and stereotyped glomerular response to injury that occur in several forms of glomerulonephritis that progress to renal failure. The key pathogenetic step that leads to glomerular scarring in unknown, but fibronectin (FN), the clotting system, macrophages, and proliferating parietal epithelial cells are known to participate. This study was designed to determine whether FN is synthesized locally, and in what molecular isoform, and whether cytokines known to promote FN synthesis are present in the crescent. Rats immunized with bovine glomerular basement membrane develop cellular crescents by 14 days and fibrous crescents and glomerulosclerosis by 35 days. In situ hybridization was performed with oligonucleotides specific for sequences common to all FN isoforms (total FN) or sequences specific for the alternatively spliced segments (EIIIA, EIIIB, and V). Throughout the time period (14, 21, and 35 days) all crescents and glomerular tufts contained cells with strong ISH signals for total and V+ mRNA, with the strongest signals present in large cellular crescents at day 21. In contrast, EIIIA+ and EIIIB+ mRNAs showed maximal abundance within sclerosing crescents at 35 days. Protein deposition of EIIIA+, EIIIB+, and V+ FN isoforms was confirmed by immunofluorescence with segment-specific FN antibodies. Transforming growth factor-beta and interleukin-1 beta, both known to promote FN synthesis, were found in cellular crescents (days 14 and 21) and were still present, but greatly diminished, in the sclerotic phase (day 35). In summary, EIIIA-, EIIIB-, and V+ FN mRNA plasma isoforms predominate in cellular crescents, whereas in the fibrosing stage, mainly the oncofetal EIIIA+, EIIIB+, and V+ isoforms are synthesized and accumulate. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7573372

  12. Renal tubular angiogenic dysregulation in anti-Thy1.1 glomerulonephritis.

    PubMed

    Cina, Davide P; Xu, Hui; Liu, Limin; Farkas, Laszlo; Farkas, Daniela; Kolb, Martin; Margetts, Peter J

    2011-02-01

    Peritubular vascular changes and hypoxia after glomerular injury may explain subsequent tubulointerstitial injury and fibrosis. Several studies suggested that the expected tubulointerstitial angiogenic response is actively suppressed in this setting. The mechanism of this aberrant response has not been clearly identified. We used a common model of glomerular injury in rats to assess vascular changes and to identify potential factors associated with this aberrant response. Anti-Thy1.1 antibody administration (1 or 4 weekly doses) led to a dose-dependent renal damage characterized by elevated urea and tubulointerstitial fibrosis as assessed by Picro-Sirius Red staining. We quantified peritubular capillaries using CD31 and CD34 immunohistochemistry and showed that tubular angiogenic dysregulation was associated with peritubular capillary rarefaction. Using laser capture microdissection, we demonstrated an early induction of fibrogenic and angiogenic factors in the glomeruli and a subsequent dysregulated angiogenic response in the tubulointerstitial compartment. Proximal tubules of anti-Thy1.1-treated animals had increased pigment epithelial-derived factor (PEDF) expression by immunohistochemistry. Protein taken by laser capture microdissection also showed that PEDF was upregulated. Temporally associated with PEDF expression was a transient downregulation of tubular hypoxia-inducible factor (HIF)1α. In a human proximal tubular cell culture, we show that PEDF downregulates HIF1α protein and gene expression in cells exposed to 1% oxygen. In anti-Thy1.1 glomerulonephritis, there is aberrent tubular angiogenesis associated with glomerular injury and tubulointersititial fibrosis. We showed that PEDF may be involved by downregulating HIF1α. Further work is needed to elucidate the mechanism of PEDF upregulation and action in the tubules. PMID:21048020

  13. Green Tea Polyphenol (−)-Epigallocatechin-3-Gallate Restores Nrf2 Activity and Ameliorates Crescentic Glomerulonephritis

    PubMed Central

    Zhou, Jason K.; Peng, Ai; Vaziri, Nosratola D.; Mohan, Chandra; Xu, Yan; Zhou, Xin J.

    2015-01-01

    Crescentic glomerulonephritis (GN) is the most severe form of GN and is associated with significant morbidity and mortality despite aggressive immunotherapy with steroids, cytotoxic drugs, and plasmapheresis. We examined the therapeutic efficacy of the green tea polyphenol (−)-epigallocatechin-3-gallate (EGCG, 50 mg/kg BW/day x3weeks), a potent anti-inflammatory and anti-oxidant agent, on experimental crescentic GN induced in 129/svJ mice by administration of rabbit anti-mouse glomerular basement membrane sera. Routine histology and key molecules involved in inflammatory and redox signaling were studied. EGCG treatment significantly reduced mortality, decreased proteinuria and serum creatinine, and markedly improved renal histology when compared with vehicle-treated mice. The improvements in renal function and histology were accompanied by the restoration of Nrf2 signaling (which was impaired in vehicle-treated mice) as shown by increased nuclear translocation of Nrf2 and cytoplasmic glutamate cysteine ligase catalytic subunit, glutamate cysteine ligase modifier subunit, and glutathione peroxidase. EGCG-treated mice also showed reduction in p-Akt, p-JNK, p-ERK1/2 and p-P38 as well as restoration of PPARγ and SIRT1 levels. Lower dose of EGCG (25 mg/kg BW/day x2 weeks) treatment also significantly decreased proteinuria and serum creatinine, and markedly improved renal histology when compared with vehicle-treated mice. Thus, our data illustrate the efficacy of EGCG in reversing the progression of crescentic GN in mice by targeting multiple signaling and inflammatory pathways as well as countering oxidative stress. PMID:25785827

  14. A Method of Identifying AGNs Based on Emission-Line Excess and the Nature of Low-Luminosity AGNs in the Sloan Digital Sky Survey. II. The Nature of Low-Luminosity AGNs

    NASA Astrophysics Data System (ADS)

    Tanaka, Masayuki

    2012-04-01

    We have developed a new method of identifying active galactic nuclei (AGNs) and studied the nature of low-luminosity AGNs in the Sloan Digital Sky Survey. This is the latter part of a series of papers in which we consider correlations between the AGN activities and the host-galaxy properties. Based on a sample of AGNs identified by a new method developed in the former part (2012, PASJ, 64, 36), we found that AGNs typically show extinction of τV = 1.2, and exhibit a wide range of ionization levels. The finding of ionization levels motivated us to use [O II] + [O III] as an indicator of AGN power. We found that AGNs are preferentially located in massive, red, early-type galaxies. Taking into account a selection bias of the Oxygen-excess method, we showed that strong AGNs are located in active star-forming galaxies, and that rapidly growing super-massive black holes are located in rapidly growing galaxies, which clearly shows the coevolution of super-massive black holes and their host galaxies. This is a surprising phenomenon, given that the growths of black holes and host galaxies occur on their respective physical scales which are very different. Interestingly, the AGN power does not strongly correlate with the host-galaxy mass. It seems that the mass works as a ``switch'' for activating AGNs. The absence of AGNs in low-mass galaxies might be due to the absence of super-massive black holes there, but a dedicated observation of the nuclear region of nearby low-mass galaxies would be necessary to obtain a deeper insight into it.

  15. Converting the Audience: A Conversation with Agnes Wilcox

    ERIC Educational Resources Information Center

    Becker, Becky

    2006-01-01

    This article presents a conversation with Agnes Wilcox, Executive Director of Prison Performing Arts in St. Louis, Missouri, about Prison Performing Arts. Although the average person might balk at the notion of interacting with prison inmates, finding it intimidating, worrisome, or self-sacrificial, for Wilcox, Prison Performing Arts is a…

  16. Disc outflows and high-luminosity true type 2 AGN

    NASA Astrophysics Data System (ADS)

    Elitzur, Moshe; Netzer, Hagai

    2016-06-01

    The absence of intrinsic broad-line emission has been reported in a number of active galactic nuclei (AGN), including some with high Eddington ratios. Such `true type 2 AGN' are inherent to the disc-wind scenario for the broad-line region: broad-line emission requires a minimal column density, implying a minimal outflow rate and thus a minimal accretion rate. Here we perform a detailed analysis of the consequences of mass conservation in the process of accretion through a central disc. The resulting constraints on luminosity are consistent with all the cases where claimed detections of true type 2 AGN pass stringent criteria, and predict that intrinsic broad-line emission can disappear at luminosities as high as ˜4 × 1046 erg s-1 and any Eddington ratio, though more detections can be expected at Eddington ratios below ˜1 per cent. Our results are applicable to every disc outflow model, whatever its details and whether clumpy or smooth, irrespective of the wind structure and its underlying dynamics. While other factors, such as changes in spectral energy distribution or covering factor, can affect the intensities of broad emission lines, within this scenario they can only produce true type 2 AGN of higher luminosity then those prescribed by mass conservation.

  17. The search for red AGN with 2MASS

    NASA Technical Reports Server (NTRS)

    Cutri, R. M.; Nelson, B. O.; Kirkpatrick, J. D.; Huchra, J. P.; Smith, P. S.

    2001-01-01

    We present the results of a simple, highly efficient 2MASS color-based survey that has already discovered 140 previously unknown red AGN and QSOs. These objects are near-infrared-bright and relatively nearby; the media redshift of the sample is z=0.25, and all but two have z<0.7.

  18. FLOYDS Classification of Gaia16ann as an AGN

    NASA Astrophysics Data System (ADS)

    Hosseinzadeh, G.; Arcavi, I.; Howell, D. A.; McCully, C.; Valenti, S.

    2016-07-01

    We obtained a spectrum of Gaia16ann on 2016 July 7.5 UT with the robotic FLOYDS instrument mounted on the LCOGT 2-meter telescope on Haleakala, Hawai'i. Using SNID (Blondin & Tonry 2007, ApJ, 666, 1024), we find a good fit to an AGN at redshift z=0.196.

  19. New light on obscured accretion in nearby AGN

    NASA Astrophysics Data System (ADS)

    Arevalo, Patricia

    Analyses of the Cosmic X-ray Background have shown that a substantial fraction of the black hole growth in the Universe occurred behind dense clouds of obscuring material. As such, it is critical to the study the detailed spectral characteristics of nearby obscured black holes, which provide templates for deriving accurate physical parameters from more distant obscured accretors. Hard X-rays are important in this regard, allowing us to peer more directly into the central engine of obscured sources and constrain the nature of the obscuration. The recently launched NuSTAR telescope is unique at focusing hard X-rays, producing the lowest background-contaminated spectra to date and rendering accurate, high signal-to-noise spectra up to 80 keV. NuSTAR covers precisely the energy range where the main features of obscured accretion appear and where the intrinsic emission might even shine through. Importantly, the low level of background also allows us for the first time to measure rapid variability of AGN at high X-ray energies. Both features combined are revealing the detailed nature of the engine of nearby obscured AGN, including the properties of the obscurer, the intrinsic emitted flux of the AGN and whether or not we can see through the torus at these high energies. In this talk I will show how NuSTAR data is challenging past assumptions about even the very local obscured AGN.

  20. Time Series Analysis of the UV Flickering in AGN

    NASA Technical Reports Server (NTRS)

    Robinson, Edward L.; Welsh, William F.

    2001-01-01

    Many active galactic nuclei (AGN) exhibit large-amplitude luminosity fluctuations on short timescales. The fluctuations lead to a profound conclusion: The size of the emitting region is remarkably small. This observational fact is one of the pillars supporting the AGN paradigm: Prodigious amounts of gravitational potential energy are liberated in an accretion disk around a supermassive black hole. The goals of the research were to extract from the IUE Archive the very best observational characterizations of AGN flickering, and to use these to test and develop models for AGN variability. We hoped to answer these specific questions: 1) What does the intrinsic flickering continuum spectrum look like? 2) What do the intrinsic flickering emission-line profiles look like? 3) What is the power spectrum of the flickering? 4) What is the wavelength dependence of the power spectrum? 5) Is the flickering spectrum timescale dependent? and 6) What do the high-order cross correlation functions look like? A short summary of the papers produced by this research is presented.

  1. The Role of Environment in Fueling Seyfert AGN

    NASA Astrophysics Data System (ADS)

    Hicks, Erin Kathleen Strobel

    2015-08-01

    We consider the role of environment in fueling of Seyfert AGN through a combined analysis of Hubble Space Telescope images and integral field spectroscopy of the ISM in a sample of local AGN. Using visible and near-infrared Hubble Space Telescope images and color maps of over a 100 galaxies we determine the distribution of the cold ISM, as traced by dust. We also measure the two-dimensional distribution and kinematics of the molecular gas, traced by H2 1-0 S(1) emission at 2.12 μm, down to scales of tens of parsecs using OSIRIS at Keck and SINFONI on VLT for a subset of approximately 20 of these galaxies. Informed by these kinematic measurements of the ISM we classify the nuclear dust morphologies of the full sample of galaxies and interpret the significance of these morphologies in terms of inflow. Our relatively small precursor sample (Hicks et al. 2009, Davies et al. 2014) hinted at a connection between the host galaxy environment and the primary mechanism driving gas inward such that fueling of AGN in isolated galaxies occurs primarily via secular processes (e.g. nuclear spirals) and galaxies in groups of 10-15 members via accretion of external gas. Using our expanded sample that now has the ability to reveal statistically significant trends we explore the potential influence of the galaxy environment on the fueling of Seyfert AGN.

  2. Review of Space VLBI RadioAstron studies of AGN

    NASA Astrophysics Data System (ADS)

    Gurvits, Leonid; Kovalev, Yuri

    2016-07-01

    Space VLBI offers an unrivalled resolution in studies of the AGN phenomena. Since 2011, the Russia-led SVLBI mission RadioAstron conducts observations at 92, 18, 6 and 1.3 cm with baselines an order of magnitude longer than the Earth diameter, therefore offering an order of magnitude "sharper" view at the brightest radio sources than achieved with Earth-based VLBI systems. In our presentation we will review the current status of the RadioAstron's scientific programme. Over the first 4.5 years of the in-orbit operations, the mission achieved successful VLBI detections of extragalactic continuum radio sources at all four observing bands. To date, detections on SVLBI baselines have been obtained for more than 150 AGN's at projected baselines up to 350 000 km (about 28 Earth diameters, ED). The highest resolution achieved is 14 microarcscends from 1.3 cm observations. RadioAstron is an international project; it conducts observations with up to 30 Earth-based radio telescopes located on different continents. We will review results of total intensity and polarisation imaging with extreme angular resolution of blazars and nearby active galaxies. We will also discuss typical and maximum brightness temperatures of blazar cores from the AGN Survey obtained with RadioAstron. Physical implications for the AGN jets formation, magnetic field and emission mechanism will be discussed on the basis of the results obtained to date.

  3. Fast ionized X-ray absorbers in AGNs

    NASA Astrophysics Data System (ADS)

    Fukumura, K.; Tombesi, F.; Kazanas, D.; Shrader, C.; Behar, E.; Contopoulos, I.

    2016-05-01

    We investigate the physics of the X-ray ionized absorbers often identified as warm absorbers (WAs) and ultra-fast outflows (UFOs) in Seyfert AGNs from spectroscopic studies in the context of magnetically-driven accretion-disk wind scenario. Launched and accelerated by the action of a global magnetic field anchored to an underlying accretion disk around a black hole, outflowing plasma is irradiated and ionized by an AGN radiation field characterized by its spectral energy density (SED). By numerically solving the Grad-Shafranov equation in the magnetohydrodynamic (MHD) framework, the physical property of the magnetized disk-wind is determined by a wind parameter set, which is then incorporated into radiative transfer calculations with xstar photoionization code under heating-cooling equilibrium state to compute the absorber's properties such as column density N_H, line-of-sight (LoS) velocity v, ionization parameter ξ, among others. Assuming that the wind density scales as n ∝ r-1, we calculate theoretical absorption measure distribution (AMD) for various ions seen in AGNs as well as line spectra especially for the Fe Kα absorption feature by focusing on a bright quasar PG 1211+143 as a case study and show the model's plausibility. In this note we demonstrate that the proposed MHD-driven disk-wind scenario is not only consistent with the observed X-ray data, but also help better constrain the underlying nature of the AGN environment in a close proximity to a central engine.

  4. Fast Ionized X-ray Absorbers in AGNs

    NASA Astrophysics Data System (ADS)

    Fukumura, K.; Tombesi, F.; Kazanas, D.; Shrader, C.; Behar, E.; Contopoulos, I.

    2015-07-01

    We present a study of X-ray ionization of MHD accretion-disk wind models in an effort to explain the highly-ionized ultra-fast outflows (UFOs) identified as X-ray absorbers recently detected in various sub-classes of Seyfert AGNs. Our primary focus is to show that magnetically-driven outflows are physically plausible candidates to account for the AGN X-ray spectroscopic observations. We calculate its X-ray ionization and the ensuing X-ray absorption line spectra in comparison with an XXM-Newton/EPIC spectrum of the narrow-line Seyfert AGN, PG 1211+143. We find, through identifying the detected features with Fe Kα transitions, that the absorber has a characteristic ionization parameter of log(xi[erg cm/s]) = 5-6 and a hydrogen-equivalent column density on the order of 1e23 cm-2, outflowing at a sub-relativistic velocity of v/c = 0.1-0.2. The best-fit model favors its radial location at R = 200 Rs (Rs is the Schwarzschild radius), with a disk inner truncation radius at Rt = 30Rs. The overall K-shell feature in data is suggested to be dominated by Fe XXV with very little contribution from Fe XXVI and weakly-ionized iron, which is in a good agreement with a series of earlier analysis of the UFOs in various AGNs including PG 1211+143.

  5. First Results from the NuSTAR AGN Physics Program

    NASA Astrophysics Data System (ADS)

    Brenneman, Laura; Fuerst, F.; Matt, G.; Walton, D.; Madejski, G. M.; Marinucci, A.; Elvis, M.; Risaliti, G.; Harrison, F.; Stern, D.; Boggs, S.; Christensen, F.; Craig, W. W.; Zhang, W.; NuSTAR Team

    2013-04-01

    The Nuclear Spectroscopic Telescope Array (NuSTAR, launched June 2012) is revolutionizing our knowledge of the physics at work in active galactic nuclei (AGN). With its high collecting area, focusing optics and low background from 3-79 keV, NASA's newest X-ray observatory is providing an unprecedented look at the spectral and timing properties of AGN in this energy range, which have been notoriously difficult to access. NuSTAR has observed several AGN to date simultaneously with XMM-Newton, Suzaku and/or Swift for the purposes of understanding their coronal properties (e.g., plasma temperature, optical depth) and measuring the spins of their supermassive black holes. We present the first results from these observing campaigns, highlighting the spectral and timing analysis of the bright, nearby AGN IC 4329A, NGC 4151, NGC 1365 and MCG--6-30-15. These are the highest signal-to-noise datasets ever obtained across the 0.2-79 keV energy band for these three sources, allowing us to cleanly deconvolve the X-ray continuum, absorption and reflection components in each galaxy for the first time via time-averaged and time-resolved spectroscopy.

  6. A Degeneracy in DRW Modelling of AGN Light Curves

    NASA Astrophysics Data System (ADS)

    Kozłowski, Szymon

    2016-04-01

    Individual light curves of active galactic nuclei (AGNs) are nowadays successfully modelled with the damped random walk (DRW) stochastic process, characterized by the power exponential covariance matrix of the signal, with the power β = 1. By Monte Carlo simulation means, we generate mock AGN light curves described by non-DRW stochastic processes (0.5 ≤ β ≤ 1.5 and β ≠ 1) and show they can be successfully and well-modelled as a single DRW process, obtaining comparable goodness of fits. A good DRW fit, in fact, may not mean that DRW is the true underlying process leading to variability and it cannot be used as a proof for it. When comparing the input (non-DRW) and measured (DRW) process parameters, the recovered time scale (amplitude) increases (decreases) with the increasing input β. In practice, this means that the recovered DRW parameters may lead to biased (or even non-existing) correlations of the variability and physical parameters of AGNs if the true AGN variability is caused by non-DRW stochastic processes. The proper way of identifying the processes leading to variability are model-independent structure functions and/or power spectral densities and then using such information on the covariance matrix of the signal in light curve modelling.

  7. Sexual Freedom Rights for Adolescents? A Rejoinder to Agnes Tellings

    ERIC Educational Resources Information Center

    Steutel, Jan

    2009-01-01

    Agnes Tellings rightly observes that adolescents, if compared with pre-pubescent children, are much more capable of making their own choices and therefore should be granted much more freedom to arrange their own lives. However, the capacity of adolescents to make prudent choices still seems to be below the threshold of competence. Therefore,…

  8. Agnes Mary Clerke: Ever-popular historian of astronomy

    NASA Astrophysics Data System (ADS)

    Brück, M.

    In her day, Agnes Mary Clerke (1842-1907) was the English-speaking world's most highly regarded writer on the rapidly developing science of astrophysics. This account outlines how, without any formal education but with a deep interest in learning, this remarkable woman rose to the admired position she still holds as a leading historian of astronomy and astrophysics.

  9. A degeneracy in DRW modelling of AGN light curves

    NASA Astrophysics Data System (ADS)

    Kozłowski, Szymon

    2016-07-01

    Individual light curves of active galactic nuclei (AGNs) are nowadays successfully modelled with the damped random walk (DRW) stochastic process, characterized by the power exponential covariance matrix of the signal, with the power β = 1. By Monte Carlo simulation means, we generate mock AGN light curves described by non-DRW stochastic processes (0.5 ≤ β ≤ 1.5 and β ≠ 1) and show they can be successfully and well modelled as a single DRW process, obtaining comparable goodness of fits. A good DRW fit, in fact, may not mean that DRW is the true underlying process leading to variability and it cannot be used as a proof for it. When comparing the input (non-DRW) and measured (DRW) process parameters, the recovered time-scale (amplitude) increases (decreases) with the increasing input β. In practice, this means that the recovered DRW parameters may lead to biased (or even non-existing) correlations of the variability and physical parameters of AGNs if the true AGN variability is caused by non-DRW stochastic processes. The proper way of identifying the processes leading to variability are model-independent structure functions and/or power spectral densities and then using such information on the covariance matrix of the signal in light-curve modelling.

  10. Understanding AGNs in the Local Universe through Optical Reverberation Mapping

    NASA Astrophysics Data System (ADS)

    Pei, Liuyi

    2016-01-01

    I present the results of observational projects aimed at measuring the mass of the black hole at the center of active galactic nuclei (AGNs) and understanding the structure and kinematics of the broad-line emitting gas within the black hole's sphere of influence.The first project aims to measure the black hole mass in the Kepler-field AGN KA1858. We obtained simultaneous spectroscopic data from the Lick Observatory 3-m telescope using the Kast Double Spectrograph and photometry data from five ground-based telescopes, and used reverberation mapping (RM) techniques to measure the emission-line light curves' lags relative to continuum variations. We obtained lags for H-beta, H-gamma, H-delta, and He II, and obtained the first black hole mass measurement for this object. Our results will serve as a reference point for future studies on relations between black hole mass and continuum variability characteristics using Kepler AGN light curves.The second project, in collaboration with the AGN STORM team, aims to understand the structure and dynamics of the broad line region (BLR) in NGC 5548 in both UV and optical wavelengths. To supplement 6 months of HST UV observations, we obtained simultaneous optical spectroscopic data from six ground-based observatories. We obtained emission-line lags for the optical H-beta and He II lines as well as velocity-resolved lag measurements for H-beta. We also compared the velocity-resolved lags for H-beta to the UV emission lines C IV and Ly-alpha and found similar lag profiles for all three lines.Finally, I will discuss my contributions to two other collaborations in AGN RM. A key component in RM is monitoring continuum variability, which is often done through ground-based photometry. I will present a pipeline that performs aperture photometry on any number of images of an AGN with WCS coordinates and immediately produces relative light curves. This pipeline enables quick looks of AGN variability in real time and has been used in the

  11. Type 1 AGN at low z- I. Emission properties

    NASA Astrophysics Data System (ADS)

    Stern, Jonathan; Laor, Ari

    2012-06-01

    We analyse the emission properties of a new sample of 3579 type 1 AGN, selected from Sloan Digital Sky Survey (SDSS) Data Release 7 based on the detection of broad Hα emission. The sample extends over a broad Hα luminosity LbHα of ? and a broad Hα full width at half-maximum (FWHM) of ?, which covers the range of black hole mass 106 < MBH/M⊙ < 109.5 and luminosity in Eddington units 10-3 < L/LEdd < 1. We combine ROSAT, GALEX and 2MASS observations to form the spectral energy distribution (SED) from 2.2 ?m to 2 keV. We find the following. (1) The distribution of the Hα FWHM values is independent of luminosity. (2) The observed mean optical-ultraviolet (optical-UV) SED is well matched by a fixed-shape SED of luminous quasars, which scales linearly with LbHα, and a host galaxy contribution. (3) The host galaxy r-band (fibre) luminosity function follows well the luminosity function of inactive non-emission-line galaxies (NEGs), consistent with a fixed fraction of ˜3 per cent of NEGs hosting an AGN, regardless of the host luminosity. (4) The hosts of lower luminosity AGN have a mean z-band luminosity and u-z colour which are identical to NEGs with the same redshift distribution. With increasing LbHα the AGN hosts become bluer and less luminous than NEGs. The implied increasing star formation rate with LbHα is consistent with the relation for SDSS type 2 AGN of similar bolometric luminosity. (5) The optical-UV SED of the more luminous AGN shows a small dispersion, consistent with dust reddening of a blue SED, as expected for thermal thin accretion disc emission. (6) There is a rather tight relation between ? and LbHα, which provides a useful probe for unobscured (true) type 2 AGN. (7) The primary parameter that drives the X-ray to UV emission ratio is luminosity, rather than MBH or L/LEdd.

  12. A radio view of high-energy emitting AGNs

    NASA Astrophysics Data System (ADS)

    Schulz, Robert Frank

    2016-07-01

    Active galactic nuclei (AGNs) are among the most energetic objects in the Universe. These galaxies that are dominated in part or even throughout the electromagnetic spectrum by emission from their central, compact region. AGNs are extensively studied by multi-wavelength observations. In the standard picture, the main driver of an AGN is a supermassive black hole (SMBH) in its centre that is surrounded by an accretion disk. Perpendicular to the disk, in the vicinity of highly magnetized SMBH relativistic outflows of plasma, so-called jets, can form on either side that can reach far beyond the host galaxy. Only about 10% of all AGNs are dominated by emission from these jets due to relativistic beaming effects and these so-called blazars dominate the extragalactic gamma-ray sky. It is commonly accepted that the low-energy emission (radio to UV/X-ray) is due to synchrotron emission from the jet. The high-energy emission is considered to stem from inverse-Compton scattering of photons on the jet particles, but different sources for these photons are discussed (internal or external to the AGN) and other models for the high-energy emission have also been proposed. The nature of the high-energy emission is strongly linked to the location of the emission region in the jet which requires a detailed understanding of the formation and evolution of jets. Radio observations especially using very long baseline interferometry (VLBI) provide the best way to gain direct information on the intrinsic properties of jets down to sub-pc scales, close to their formation region. In this thesis, I focus on the properties of three different AGNs, IC 310, PKS2004-447, and 3C 111 that belong to the small non-blazar population of gamma-ray-loud AGNs. I study them in detail with a variety of radio astronomical instruments with respect to their high-energy emission and in the context of the large monitoring programmes MOJAVE (Monitoring Of Jets in Active galactic nuclei with VLBA Experiments) and

  13. Host Galaxy Properties of the Swift BAT Ultra Hard X-Ray Selected AGN

    NASA Technical Reports Server (NTRS)

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa M.; Baumgartner, Wayne; Tueller, Jack; Gehrels, Neil; Valencic, Lynne

    2011-01-01

    We have assembled the largest sample of ultra hard X-ray selected (14-195 keV) AGN with host galaxy optical data to date, with 185 nearby (z<0.05), moderate luminosity AGN from the Swift Burst Alert Telescope (BAT) sample. The BAT AGN host galaxies have intermediate optical colors (u -- r and g -- r) that are bluer than a comparison sample of inactive galaxies and optically selected AGN from the Sloan Digital Sky Survey (SDSS) which are chosen to have the same stellar mass. Based on morphological classifications from the RC3 and the Galaxy Zoo, the bluer colors of BAT AGN are mainly due to a higher fraction of mergers and massive spirals than in the comparison samples. BAT AGN in massive galaxies (log Stellar Mass >10.5) have a 5 to 10 times higher rate of spiral morphologies than in SDSS AGN or inactive galaxies. We also see enhanced far-IR emission in BAT AGN suggestive of higher levels of star formation compared to the comparison samples. BAT AGN are preferentially found in the most massive host galaxies with high concentration indexes indicative of large bulge-to-disk ratios and large supermassive black holes. The narrow-line (NL) BAT AGN have similar intrinsic luminosities as the SDSS NL Seyferts based on measurements of [O III] Lambda 5007. There is also a correlation between the stellar mass and X-ray emission. The BAT AGN in mergers have bluer colors and greater ultra hard X-ray emission compared to the BAT sample as whole. In agreement with the Unified Model of AGN, and the relatively unbiased nature of the BAT sources, the host galaxy colors and morphologies are independent of measures of obscuration such as X-ray column density or Seyfert type. The high fraction of massive spiral galaxies and galaxy mergers in BAT AGN suggest that host galaxy morphology is related to the activation and fueling of local AGN.

  14. Cooperation of ETV6/RUNX1 and BCL2 enhances immunoglobulin production and accelerates glomerulonephritis in transgenic mice.

    PubMed

    Bauer, Eva; Schlederer, Michaela; Scheicher, Ruth; Horvath, Jaqueline; Aigner, Petra; Schiefer, Ana-Iris; Kain, Renate; Regele, Heinz; Hoermann, Gregor; Steiner, Günter; Kenner, Lukas; Sexl, Veronika; Villunger, Andreas; Moriggl, Richard; Stoiber, Dagmar

    2016-03-15

    The t(12;21) translocation generating the ETV6/RUNX1 fusion gene represents the most frequent chromosomal rearrangement in childhood leukemia. Presence of ETV6/RUNX1 alone is usually not sufficient for leukemia onset, and additional genetic alterations have to occur in ETV6/RUNX1-positive cells to cause transformation. We have previously generated an ETV6/RUNX1 transgenic mouse model where the expression of the fusion gene is restricted to CD19-positive B cells. Since BCL2 family members have been proposed to play a role in leukemogenesis, we investigated combined effects of ETV6/RUNX1 with exogenous expression of the antiapoptotic protein BCL2 by crossing ETV6/RUNX1 transgenic animals with Vav-BCL2 transgenic mice. Strikingly, co-expression of ETV6/RUNX1 and BCL2 resulted in significantly shorter disease latency in mice, indicating oncogene cooperativity. This was associated with faster development of follicular B cell lymphoma and exacerbated immune complex glomerulonephritis. ETV6/RUNX1-BCL2 double transgenic animals displayed increased B cell numbers and immunoglobulin titers compared to Vav-BCL2 transgenic mice. This led to pronounced deposition of immune complexes in glomeruli followed by accelerated development of immune complex glomerulonephritis. Thus, our study reveals a previously unrecognized synergism between ETV6/RUNX1 and BCL2 impacting on malignant disease and autoimmunity. PMID:26919255

  15. Cooperation of ETV6/RUNX1 and BCL2 enhances immunoglobulin production and accelerates glomerulonephritis in transgenic mice

    PubMed Central

    Bauer, Eva; Schlederer, Michaela; Scheicher, Ruth; Horvath, Jaqueline; Aigner, Petra; Schiefer, Ana-Iris; Kain, Renate; Regele, Heinz; Hoermann, Gregor; Steiner, Günter; Kenner, Lukas; Sexl, Veronika; Villunger, Andreas; Moriggl, Richard; Stoiber, Dagmar

    2016-01-01

    The t(12;21) translocation generating the ETV6/RUNX1 fusion gene represents the most frequent chromosomal rearrangement in childhood leukemia. Presence of ETV6/RUNX1 alone is usually not sufficient for leukemia onset, and additional genetic alterations have to occur in ETV6/RUNX1-positive cells to cause transformation. We have previously generated an ETV6/RUNX1 transgenic mouse model where the expression of the fusion gene is restricted to CD19-positive B cells. Since BCL2 family members have been proposed to play a role in leukemogenesis, we investigated combined effects of ETV6/RUNX1 with exogenous expression of the antiapoptotic protein BCL2 by crossing ETV6/RUNX1 transgenic animals with Vav-BCL2 transgenic mice. Strikingly, co-expression of ETV6/RUNX1 and BCL2 resulted in significantly shorter disease latency in mice, indicating oncogene cooperativity. This was associated with faster development of follicular B cell lymphoma and exacerbated immune complex glomerulonephritis. ETV6/RUNX1-BCL2 double transgenic animals displayed increased B cell numbers and immunoglobulin titers compared to Vav-BCL2 transgenic mice. This led to pronounced deposition of immune complexes in glomeruli followed by accelerated development of immune complex glomerulonephritis. Thus, our study reveals a previously unrecognized synergism between ETV6/RUNX1 and BCL2 impacting on malignant disease and autoimmunity. PMID:26919255

  16. [A case of rapidly progressive glomerulonephritis in the course of Wegener's granulomatosis].

    PubMed

    Idasiak-Piechocka, I; Oko, A; Łochyńska, K; Woźniak, A; Czekalski, S

    2000-01-01

    Wegener's granulomatosis (WG) is characterized by granulomatous vasculitis of the respiratory tract and glomerulonephritis (GN). Prognosis of this disease is poor and about 20% of untreated patients die after one year from the onset. WG was recognized in 45-year-old patient on the basis of: 1) clinical symptoms (joint pain and swollen, purpura on the skin which appeared one week after respiratory tract infection, ulceration of the tonsils and lingula), 2) results of additional testing (X-chest-ray-infiltrates of both lungs), positive results of the cANCA (titre 1:640) and rapidly progressive renal failure [the increase of serum creatinine level (Pcr) from 123.7 to 707 mumol/l (1.4 to 8.0 mg/dl) during one week]. Renal biopsy revealed extracapillary GN (cellular crescents in 7 out of 8 glomeruli and scattered foci of fibrinoid necrosis of capillary walls in all). At the beginning of the treatment Pcr raised to 884 mumol/l (10 mg/dl) and the patient required hemodialysis. He was treated with methylprednisolone (M) at flash doses of 1000 mg/24 h by three days followed by 125 mg/24 h i.v.--because of peptic ulcer, with cyclophosphamide (C-150 mg/24 h p.p.), with trimetoprim/sulphametoxazole, with pentoxifylline and omeprazol. After six weeks of the treatment in the control kidney biopsy sclerotic changes in 10 out of 13 glomeruli and diffuse interstitial fibrosis were found. However, during the same time, we observed clinical remission of the disease and the decrease of Pcr to 176.8 mumol/l (2 mg/dl). The M dosis was reduced by 5 mg every weeks and the C dosis--to 50 mg (because of the increase of aminotransferase levels) After six months of the treatment Pcr was 132.6 mumol/l (1.5 mg/dl) and CANCA titer was 1:16. In this case of RPGN, despite off the progression of the morphological changes in the kidney, we obtained the clinical remission of the disease and significant decrease of Pcr level. These results suggest that aggressive treatment of WG is justified even in

  17. Podocyte Detachment Is Associated with Renal Prognosis in ANCA-Associated Glomerulonephritis

    PubMed Central

    Zou, Rong; Wang, Su-xia; Liu, Gang; Yu, Feng; Chen, Min; Zhao, Ming-Hui

    2016-01-01

    Abstract The prognosis of antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis (ANCA-GN) is unfavorable despite immunosuppressive therapy. It has been suggested that the loss of podocytes is a hallmark of progressive kidney disease. However, it is unclear about podocyte injuries and their predictive values on the prognosis in ANCA-GN. Therefore, the current study aimed to investigate the podocyte injury in renal histopathology and its association with renal prognosis of patients with ANCA-GN. A total of 170 patients with ANCA-GN were recruited in this study. Morphometric investigation of podocytes by electron microscopy including foot process width (FPW), podocyte density per glomerulus (Nv), and glomerular basement membrane (GBM) width were measured and calculated in ANCA-GN patients. Cox regression analysis was used to analyze the association between podocyte injuries and prognosis of patients with ANCA-GN. Foot processes broadening, podocyte detachment, and GBM thickening could be observed in electron micrographs in the specimens of 158/170 (92.9%), 142/170 (83.5%), and 150/170 (88.2%) patients, respectively. Compared with normal controls, FPW and GBM width in ANCA-GN patients was significantly higher (1269.39 ± 680.19 vs 585.81 ± 77.16, P = 0.004; 668.23 ± 208.73 vs 354.23 ± 52.70, P = 0.000, respectively), while the podocyte density was significantly lower (55.90 ± 36.32 vs 255.23 ± 47.29, P = 0.000). The podocyte density was independently associated with the recovery of renal function in logistic regression analysis (OR, 1.083; 95% CI, 1.025–1.440; P = 0.005). Furthermore, multivariate analysis revealed that podocyte density was an independent predictor of end-stage renal disease (ESRD) (model A: HR, 0.950; 95% CI, 0.919–1.982; P = 0.002; model B: HR, 0.953; 95% CI, 0.922–0.985; P = 0.004). Podocyte structural damage and detachment occurred frequently in patients with ANCA

  18. Epidemiology of Histologically Proven Glomerulonephritis in Africa: A Systematic Review and Meta-Analysis

    PubMed Central

    Okpechi, Ikechi G.; Ameh, Oluwatoyin I.; Bello, Aminu K.; Ronco, Pierre; Swanepoel, Charles R.; Kengne, Andre P.

    2016-01-01

    Background and aim Glomerulonephritis (GN) is a leading cause of end-stage renal disease (ESRD) in Africa. Data on epidemiology and outcomes of glomerular diseases from Africa is still limited. We conducted a systematic review on the epidemiology of histologically proven glomerular diseases in Africa between 1980 and 2014. Materials and methods We searched literature using PubMed, AfricaWide, the Cumulative Index to Nursing and Allied Health Literature on EBSCO Host, Scopus, African Journals online databases, and the African Index Medicus, for relevant studies. The review was conducted using standard methods and frameworks using only biopsy-confirmed data. Results Twenty four (24) studies comprising 12,093 reported biopsies from 13 countries were included in this analysis. The median number of biopsies per study was 127.0 (50–4436), most of the studies (70.0%) originated from North Africa and the number of performed kidney biopsies varied from 5.2 to 617 biopsies/year. Nephrotic syndrome was the commonest indication of renal biopsy. The frequency of reported primary pathologic patterns included, minimal change disease (MCD); 16.5% (95%CI: 11.2–22.6), focal segmental glomerulosclerosis (FSGS); 15.9% (11.3–21.1), mesangiocapillary GN (MCGN); 11.8% (9.2–14.6), crescentic GN; 2.0% (0.9–3.5) and IgA nephropathy 2.8% (1.3–4.9). Glomerular diseases related to hepatitis B and systemic lupus erythematosus had the highest prevalence among assessed secondary diseases: 8.4% (2.0–18.4) and 7.7% (4.5–11.7) respectively. There was no evidence of publication bias and regional differences were seen mostly for secondary GNs. Conclusions Glomerular diseases remain poorly characterized in sub-Saharan Africa due to declining renal biopsy rates and consequent paucity of data on pathologic patterns of key renal diseases. Development of renal biopsy registries in Africa is likely to enable adequate characterization of the prevalence and patterns of glomerular diseases

  19. Interleukin-1 receptor antagonist ameliorates experimental anti-glomerular basement membrane antibody-associated glomerulonephritis.

    PubMed Central

    Tang, W W; Feng, L; Vannice, J L; Wilson, C B

    1994-01-01

    The contribution of IL-1 to leukocyte infiltration in anti-glomerular basement membrane (GBM) antibody (Ab) glomerulonephritis (GN) was examined by the administration of a specific IL-1 receptor antagonist (IL-1ra). Lewis rats received anti-GBM Ab or normal rabbit serum and were treated with either 0.9% saline or 6 mg IL-1ra over a 24-h time period. Plasma IL-1ra concentration was 2,659 +/- 51 ng/ml 4 h after anti-GBM Ab and IL-1ra administration. PMN and monocyte/macrophage infiltration declined 39% (9.8 +/- 1.9 to 6.0 +/- 1.5 PMN/glomerulus, P < 0.001) and 29% (4.9 +/- 0.8 to 3.5 +/- 0.8 ED-1 cells/glomerulus, P = 0.002) with IL-1ra treatment at 4 h, respectively. Similarly, the number of glomerular cells staining for lymphocyte function-associated molecule-1 beta (CD18) declined 39% from 16.7 +/- 1.9 to 10.7 +/- 1.6 cells/glomerulus at 4 h (P = 0.0001). This was associated with a decrease in glomerular intracellular adhesion molecule-1 expression. The mean glomerular intracellular adhesion molecule-1 score in anti-GBM Ab GN rats treated with IL-1ra was less than that of rats administered anti-GBM Ab and 0.9% saline at 4 (2.0 +/- 0.2 vs 2.5 +/- 0.2, P < 0.05) and 24 (2.5 +/- 0.1 vs 3.1 +/- 0.2, P = 0.0001) h. These immunopathologic changes correlated with a 50% reduction in proteinuria from 147 +/- 34 to 75 +/- 25 mg/d (P < 0.002). Treatment with IL-1ra did not affect the steady state mRNA expression of either IL-1 beta or TNF alpha. An increase in the IL-1ra dose to 30 mg given within the initial 4 h provided no additional benefit. The decline in PMN and monocyte/macrophage infiltration of the glomerulus at 4 h was similar to that found in the initial study. Furthermore, the protective benefit of IL-1ra was abrogated by doubling the dose of the anti-GBM Ab GN, despite administering high dose IL-1ra (30 mg). In these studies, detectable IL-1ra was found in the serum of untreated anti-GBM Ab GN controls. These data suggest a positive yet limited role for IL-1ra in

  20. Serum levels of 12 renal function and injury markers in patients with glomerulonephritis.

    PubMed

    Serwin, Natalia M; Wiśniewska, Magda; Jesionowska, Anna; Skwirczyńska, Edyta; Marcinowska, Zuzanna; Dołęgowska, Barbara

    2016-08-01

    INTRODUCTION    Glomerulonephritis (GN) is a complex disease that affects the function of the whole nephron. There are few data on the serum levels of the most common biomarkers of kidney function and injury in GN, or the studies provide ambiguous results. OBJECTIVES    The aim of the study was to evaluate the levels of known kidney-specific and nonspecific markers of renal function or injury in the serum of patients with diagnosed primary or secondary GN, with or without the presence of nephrotic syndrome (NS) and arterial hypertension (AH). PATIENTS AND METHODS    The study included 58 patients with diagnosed GN and 6 patients with congenital defects (CD) of the kidney and AH (CD+AH). The serum levels of β2-microglobulin (β2M), neutrophil‑gelatinase associated lipocalin (NGAL), osteopontin, trefoil factor 3 (TFF-3), calbindin, glutathione-S‑transferase- π (GST-π), interleukin 18 (IL-18), kidney injury molecule 1 (KIM-1), and monocyte chemoattractant protein 1 (MCP-1) were measured with Kidney Toxicity Panels 1 and 2 using the Bio-Plex method. Renalase levels were measured using an enzyme-linked immunosorbent assay. RESULTS    In the whole group and in the subgroups (GN, GN+AH, GN+NS, CD+AH), NGAL, KIM-1, TFF-3, IL-18, β2M, and calbindin levels correlated with estimated glomerular filtration rate (eGFR). In patients with NS, this correlation for calbindin was reversed. Renalase, MCP-1, GST-π, and osteopontin levels were independent of eGFR. Increase in IL-18 levels in the group with GN was assiociated with lower odds of the kidney disease. When this group was divided according to eGFR into subgroups G1-G5, TFF-3, NGAL, and β2M levels increased with the stage of the disease. CONCLUSIONS In patients with NS, renalase and MCP-1 might regulate each other's levels. Further studies are needed to investigate associations between renalase, MCP-1, and osteopontin as factors unrelated to eGFR in GN. NS may contribute to the loss of calbindin from

  1. Urinary Immunoglobulin G to Albumin Ratio and N-Acetyl-Beta-D-Glucosaminidase as Early Predictors of Therapeutic Response in ANCA-Associated Glomerulonephritis

    PubMed Central

    Mravljak, Marija; Vizjak, Alenka; Ferluga, Dusan; Pajek, Jernej; Kovac, Damjan; Skoberne, Andrej; Ales Rigler, Andreja; Kveder, Radoslav; Kosir, Andrej; Lindic, Jelka

    2013-01-01

    Background The aim of our study was to evaluate the prognostic value of glomerular and tubular proteinuria and tubular enzymuria as early indicators of therapeutic response to induction therapy with i.v. pulse cyclophosphamide (CyC) and methylprednisolone (MP) in patients with antineutrophil cytoplasmic antibody (ANCA) associated glomerulonephritis. Methods and Findings An observational single-center study was conducted in 30 patients with ANCA-associated glomerulonephritis. Patients were divided into subgroups with good or poor response to CyC therapy according to clinical and laboratory parameters. The diagnosis of ANCA-associated glomerulonephritis was based on the Chapel-Hill disease definitions. Good response to induction therapy was significantly associated with higher absolute values of urine N-acetyl-beta-D-glucosaminidase (NAG) to creatinine ratio (above 14.83 microcat/mol) and urine immunoglobulin G (IgG) to albumin ratio (above 0.09) at the time of diagnosis, while albuminuria or proteinuria did not have any early predictive value. The remission of renal disease was anticipated as early as 3 months after introduction of induction therapy in patients with reduction of urine NAG to creatinine ratio below the baseline value and in patients with at least 24% rise in eGFR. Conclusions Urine IgG to albumin and urine NAG to creatinine ratio are better early predictors of treatment response in patients with ANCA-associated glomerulonephritis than proteinuria or albuminuria. PMID:24349116

  2. Host Galaxy Properties of BAT Hard X-ray Selected AGN

    NASA Astrophysics Data System (ADS)

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa

    2010-07-01

    Surveys of AGN taken in the optical, UV, and soft X-rays miss an important population of obscured AGN only visible in the hard X-rays and mid-IR wavelengths. The SWIFT BAT survey in the hard X-ray range (14-195 keV) has provided a uniquely unbiased sample of 246 AGN unaffected by galactic or circumnuclear absorption [1]. Most of the sources in the survey are bright, Seyfert like AGN's with median redshift of 0.03. Of the AGN, 43% are obscured, type II AGN. We obtained 17 nights of imaging of 90 host galaxies of these AGN in 2008 at the Kitt Peak 2.1 m telescope in the SDSS ugriz filters. For the broad line sources we subtracted the AGN contribution using GALFIT. By comparing our sample of AGN to inactive galaxies in the SDSS, we find that AGN are found in the most massive galaxies and are bluer in color than inactive galaxies of comparable stellar mass. We also find a correlation between the point source optical light and hard X-ray luminosity.

  3. Host Galaxy Properties of BAT Hard X-ray Selected AGN

    SciTech Connect

    Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Winter, Lisa

    2010-07-15

    Surveys of AGN taken in the optical, UV, and soft X-rays miss an important population of obscured AGN only visible in the hard X-rays and mid-IR wavelengths. The SWIFT BAT survey in the hard X-ray range (14-195 keV) has provided a uniquely unbiased sample of 246 AGN unaffected by galactic or circumnuclear absorption [1]. Most of the sources in the survey are bright, Seyfert like AGN's with median redshift of 0.03. Of the AGN, 43% are obscured, type II AGN. We obtained 17 nights of imaging of 90 host galaxies of these AGN in 2008 at the Kitt Peak 2.1 m telescope in the SDSS ugriz filters. For the broad line sources we subtracted the AGN contribution using GALFIT. By comparing our sample of AGN to inactive galaxies in the SDSS, we find that AGN are found in the most massive galaxies and are bluer in color than inactive galaxies of comparable stellar mass. We also find a correlation between the point source optical light and hard X-ray luminosity.

  4. Galaxy Zoo: AGN may be fueled by stellar bars in the local Universe

    NASA Astrophysics Data System (ADS)

    Galloway, Melanie; Willett, Kyle; Fortson, Lucy; Galaxy Zoo Science Team

    2015-01-01

    Bars are a mechanism that have been proposed to explain how gas in the outer regions of a galaxy can be channeled inward and fuel AGN. Multiple observational studies have reported a significantly higher bar fraction in AGN than non-AGN. To accurately probe whether an excess of bars in AGN host galaxies exists because the galaxies host a bar, it is necessary to compare bar and AGN fractions at fixed mass and color, because the presence of bars strongly correlates with both. Thus, a sufficiently large sample is necessary to maintain adequate numbers in subsets of fixed mass and color. We have created a large, volume-limited sample of 19,765 disc galaxies using data from the Sloan Digital Sky Survey. By using morphological classifications from the Galaxy Zoo 2 project, we identify stellar bars in 51.8% of AGN hosts and 37.1% of star-forming disk galaxies. Once mass and color are fixed, there remains a statistically significant increase in the fraction of barred AGN over their unbarred counterparts. Using the L[O III]/MBH ratio as a measure of accretion efficiency, we also show that barred AGN do not exhibit stronger accretion than unbarred AGN at fixed mass or color. The data are consistent with a model in which bar-driven fueling does contribute to the probability of an actively growing black hole, but in which other dynamical mechanisms must contribute to AGN fueling via smaller, non-axisymmetric perturbations.

  5. Dual anti-neutrophil cytoplasmic antibody-related pauci-immune crescentic glomerulonephritis in a patient with Sjögren's syndrome.

    PubMed

    Lee, In Hee; Kim, Seong-Kyu; Kim, Min-Kyung

    2016-09-01

    Sjögren's syndrome is an autoimmune disease that primarily affects exocrine glands. Renal involvement of Sjögren's syndrome may lead to tubulointerstitial disease, whereas secondary glomerulopathies such as anti-neutrophil cytoplasmic antibody (ANCA)-related pauci-immune crescentic glomerulonephritis are rarely observed. In addition, crescent glomerulonephritis that is simultaneously positive for both myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA has never been reported in Sjögren's syndrome. Here, we report a case of pauci-immune crescentic glomerulonephritis exhibiting positivity for both MPO- and PR3-ANCAs in a patient with primary Sjögren's syndrome. A 71-year-old female was hospitalized for cough, blood-tinged sputum, and dyspnea two weeks after diagnosis with Sjögren's syndrome. On admission, serum anti-nuclear antibody, anti-Ro/SS-A antibody, MPO-ANCA, and PR3-ANCA were all positive, and serum blood urea nitrogen and creatinine (Cr) levels were 42.7 and 2.9 mg/dL, respectively. On the seventh day of hospitalization, the patient's serum Cr level was 5.7 mg/dL, indicating rapidly progressive glomerulonephritis. Renal biopsy resulted in the diagnosis of ANCA-related pauci-immune crescentic glomerulonephritis, for which intravenous methylprednisolone (7 mg/kg/day) was administered for three consecutive days, followed by combination therapy with oral prednisolone (1 mg/kg/day) and intravenous cyclophosphamide (500 mg/m(2)). The patient was positive in the Schirmer's I test, and a salivary gland biopsy showed sialadenitis with lympho-plasmacytic infiltrations. On day 28 of hospitalization, the patient was discharged after amelioration of respiratory symptoms and azotemia. At 6 months after discharge, the patient continued to receive appropriate daily medications and was negative for both MPO- and PR3-ANCAs, with a slight elevation in serum Cr levels. PMID:27384449

  6. The stability of QSO/AGN broad emission line clouds

    NASA Astrophysics Data System (ADS)

    Krinsky, I. S.; Puetter, R. C.

    1992-08-01

    Results of a numerical linear stability analysis of QSO/AGN emission-line clouds (ELCs) embedded within a confining hot intercloud medium (HIM) are reported. A first-order linear perturbation analysis reveals two important ionstabilities. The first instability is thermal in nature and arises in the interface region between the HIM and the ELC where thermal convection dominates gas heating; the growth time of the instability is approximately 1000 s, resulting in an ELC evaporation time of about 10 yr. The second instability is dynamic in nature, with the sound wave amplitude growing in response to radiative forces. The growth time of this instability is about 10 exp 6 s and essentially independent of the wavelength. The results suggest that if QSO/AGN ELCs have properties similar to those of the standard ELC model, then the broad-line region is in a constant state of flux in which ELCs continually form, are destroyed, and then re-formed.

  7. Autoepitopes and alloepitopes of type IV collagen: role in the molecular pathogenesis of anti-GBM antibody glomerulonephritis.

    PubMed

    Borza, Dorin-Bogdan

    2007-01-01

    Anti-glomerular basement membrane (anti-GBM) antibodies elicited by autoimmune or alloimmune mechanisms are associated with aggressive forms of rapid progressive glomerulonephritis. Pathogenic anti-GBM autoantibodies and alloantibodies target the noncollagenous (NC1) domains of the alpha3alpha4alpha5(IV) collagen, a major GBM component. In autoimmune anti-GBM glomerulonephritis, a breakdown of immune self-tolerance leads to the activation of autoreactive B and T cells recognizing epitopes within the alpha3NC1 subunit. In the GBM, the conformational epitopes targeted by anti-GBM autoantibodies are structurally sequestered within the alpha3alpha4alpha5NC1 hexamer complex formed upon assembly of collagen IV chains into trimeric molecules and networks. Autoantibodies selectively bind to and dissociate a subset of alpha3alpha4alpha5NC1 hexamers composed of monomer subunits, whereas hexamers containing NC1 dimer subunits are resistant to dissociation by autoantibodies. The crypticity of alpha3NC1 autoepitopes suggests that self-tolerance to alpha3(IV) collagen is broken by structural alterations of the native alpha3alpha4alpha5NC1 hexamer that unmask normally sequestered epitopes, triggering an autoimmune reaction. Post-transplant anti-GBM nephritis in the renal allograft of transplanted Alport patients is mediated by an alloimmune reaction to the NC1 domains of alpha3alpha4alpha5(IV) collagen, present in the allograft GBM but absent from Alport basement membranes. Alloantibodies from patients with autosomal-recessive Alport syndrome predominantly bind to the alpha3NC1 domain, whereas alloantibodies from X-linked Alport patients target preferentially, though not exclusively, epitopes within the alpha5NC1 subunit. The accessibility of the alloantigenic sites within the alpha3alpha4alpha5NC1 hexamers, contrasting with the crypticity of autoantigenic sites, suggest that different molecular forms of alpha3alpha4alpha5(IV) collagen initiate the immunopathogenic responses in

  8. Four Dual AGN Candidates Observed with the VLBA

    NASA Astrophysics Data System (ADS)

    Gabányi, K. É.; An, T.; Frey, S.; Komossa, S.; Paragi, Z.; Hong, X.-Y.; Shen, Z.-Q.

    2016-08-01

    According to hierarchical structure formation models, merging galaxies are expected to be seen in different stages of coalescence. However, there are currently no straightforward observational methods to either select or to confirm a large number of dual active galactic nucleus (AGN) candidates. Most attempts involve obtaining a better understanding of double-peaked narrow emission line sources, in order to distinguish the objects for which the emission lines originate from narrow-line kinematics or jet-driven outflows, from those which might harbor dual AGNs. We observed four such candidate sources with the Very Long Baseline Array (VLBA), at 1.5 GHz with a ∼10 mas angular resolution, for which the spectral profiles of AGN optical emission suggested the existence of dual AGNs. In SDSS J210449.13–000919.1 and SDSS J23044.82–093345.3 the radio structures are aligned with the optical emission features, thus the double-peaked emission lines might be the results of jet-driven outflows. In the third detected source SDSS J115523.74+150756.9, the radio structure is less extended and is oriented nearly perpendicular to the position angle derived from optical spectroscopy. The fourth source remained undetected with the VLBA, but it was imaged with the Very Large Array at arcsec resolution a few months before our observations, suggesting the existence of an extended radio structure. We did not detect two radio-emitting cores in any of the four sources, a convincing signature of duality.

  9. Observational aspects of AGN jets at high energy

    NASA Astrophysics Data System (ADS)

    Kataoka, Jun

    2015-03-01

    For the last two decades, significant and dramatic progress has been made in understanding astrophysical jet sources, particularly in the X-ray and gamma-ray energy bands. For example, the Chandra X-ray observatory reveals a number of AGN jets extending from kpc to Mpc scales. More recently, the Fermi Gamma-ray Space Telescopes launched in 2008 started monitoring the gamma-ray sky with excellent sensitivity of about ten times greater than that of EGRET onboard CGRO, and has detected more than 2,000 sources (mostly AGNs) as of 2014. Moreover, Fermi-LAT has discovered gamma-ray emissions not only from blazars but from a dozen radio galaxies not previously known to emit gamma-rays. Closer to home, the Fermi-bubbles were discovered to extend 50 degrees above and below the Galactic center. These large scale diffuse gamma-ray structures are similar in structure to AGN lobes such as those seen in Cen A and provide evidence for past activity in our Galactic center. In this review, I will first summarize recent highlights of large scale jets in radio galaxies, specifically resolved by the Chandra X-ray observatory. Next I will move on to the gamma-ray sky to present some highlights from Fermi-LAT observations of ``misaligned'' blazars, namely radio galaxies. I will discuss a unification scheme connecting blazars and misaligned radio galaxies. In the last part, I will also briefly comment on recent multiband observations of the Fermi-bubble and possible impacts on the AGN jet physics in the near future.

  10. X-ray AGN Clustering, Bias & Accretion mode

    NASA Astrophysics Data System (ADS)

    Plionis, Manolis; Koutoulidis, Lazaros; Georgantopoulos, Ioannis; Fanidakis, Nikolaos

    2012-09-01

    We present the spatial clustering properties of 1466 X-ray selected AGN compiled from the Chandra CDF-N, CDF-S, eCDF-S, COSMOS and AEGIS fields in the 0.5-8 keV band. The X-ray sources span the redshift interval 0AGN bias and the corresponding dark-matter host halo mass, are significantly higher than the corresponding values of optically selected AGN (at the same redshifts. The redshift evolution of the X-ray selected AGN bias indicates, in agreement with other recent studies, that a unique dark-matter halo mass does not fit well the bias at all the different redshifts probed. Furthermore, we investigate if there is a dependence of the clustering strength on X-ray luminosity, applying a procedure to disentangle the dependence of clustering on redshift. We find indications for a positive dependence of the clustering length on X-ray luminosity, in the sense that the more luminous sources have a larger clustering length and hence a higher dark-matter halo mass.

  11. Type 1 AGN at low z. I. Emission properties

    NASA Astrophysics Data System (ADS)

    Stern, J.; Laor, A.

    2012-07-01

    We analyze the emission properties of a new sample of 3 596 type 1 AGN, selected from the SDSS DR7 based on the detection of broad Hα emission. The sample extends over a broad Hα luminosity LbHα of 1040-1044 erg s-1 and a broad Hα FWHM of 1 000-25 000 km s-1, which covers the range of black hole mass 106 < MBH/Modot < 109.5 and luminosity in Eddington units 10-3 < L/LEdd < 1. We combine ROSAT, GALEX and 2MASS observations to form the SED from 2.2 μm to 2 keV. We find the following: 1. The distribution of the Hα FWHM values is independent of luminosity. 2. The observed mean optical-UV SED is well matched by a fixed shape SED of luminous quasars, which scales linearly with LbHα, and a host galaxy contribution. 3. The host galaxy r-band (fibre) luminosity function follows well the luminosity function of inactive non-emission line galaxies (NEG), consistent with a fixed fraction of ~ 3% of NEG hosting an AGN, regardless of the host luminosity. 4. The optical-UV SED of the more luminous AGN shows a small dispersion, consistent with dust reddening of a blue SED, as expected for thermal thin accretion disc emission. 5. There is a rather tight relation of νLν(2 keV) and LbHα, which provides a useful probe for unobscured (true) type 2 AGN.

  12. Alignment of Stellar and AGN Accretion Disks from SDSS Data

    NASA Astrophysics Data System (ADS)

    Lagos, Claudia del P.; Padilla, Nelson D.; Strauss, Michael A.; Hao, Lei

    2010-05-01

    Lagos, Padilla & Cora (2009) show that if alignments between the galaxy kinematics and the AGN system were to occur, massive galaxies should host BHs with high spin values, regardless of the detailed physics of the BH. Since the BH spin regulates the mass-to-energy conversion (Marconi et al. 2004) and possibly the existence of radio jets (Sikora et al. 2007), this study has a strong impact in our understanding of galaxy formation.

  13. Near-UV Snapshot Survey of Low Luminosity AGNs

    NASA Astrophysics Data System (ADS)

    Gonzalez-Delgado, Rosa

    2005-07-01

    Low-luminosity active galactic nuclei {LLAGNs} comprise 30% of all bright galaxies {B<12.5} and are the most common type of AGN. These include low-luminosity Seyfert galaxies, LINERs, and transition-type objects {TOs, also called weak-[OI] LINERs}. What powers them is still at the forefront of AGN research. To unveil the nature of the central source we propose a near-UV snapshot survey of 50 nearby LLAGNs using ACS/HRC and the filter {F330W}, a configuration which is optimal to detect faint star forming regions around their nuclei. These images will complement optical and near-IR images available in the HST archive, providing a panchromatic atlas of the inner regions of these galaxies, which will be used to study their nuclear stellar population. Our main goals are to: 1} Investigate the presence of nuclear unresolved sources that can be attributed to an AGN; 2} Determine the frequency of nuclear and circumnuclear stellar clusters, and whether they are more common in Transition Objects {TOs} than in LINERs; 3} Characterize the sizes, colors, luminosities, masses and ages of these clusters; 4} Derive the luminosity function of star clusters and study their evaporation over time in the vicinity of AGNs. Finally, the results of this project will be combined with those of a previous similar one for Seyfert galaxies in order to compare the nature of the nuclear sources and investigate if there could be an evolution from Seyferts to TOs and LINERs. By adding UV images to the existing optical and near-IR ones, this project will also create an extremely valuable database for astronomers with a broad range of scientific interests.

  14. The Multiwavelength AGN Population and the X-ray Background

    NASA Astrophysics Data System (ADS)

    Treister, Ezequiel; Urry, Claudia M.; Schawinski, Kevin; Simmons, Brooke D.; Natarajan, Priyamvada; Volonteri, Marta

    2014-07-01

    In order to fully understand galaxy formation we need to know when in the cosmic history are supermassive black holes (SMBHs) growing more intensively, in what type of galaxies this growth is happening and what fraction of these sources are invisible at most wavelengths due to obscuration. Active Galactic Nuclei (AGN) population synthesis models that can explain the spectral shape and intensity of the cosmic X-ray background (CXRB) indicate that most of the SMBH growth occurs in moderate-luminosity (L X ~ 1044 erg/s) sources (Seyfert-type AGN), at z~ 0.5-1 and in heavily obscured but Compton-thin, NH ~ 1023cm-2, systems. However, this is not the complete history, as a large fraction of black hole growth does not emit significantly in X-rays either due to obscuration, intrinsic low luminosities or large distances. The integrated intensity at high energies indicates that a significant fraction of the total black hole growth, 22%, occurs in heavily-obscured systems that are not individually detected in even the deepest X-ray observations. We further investigate the AGN triggering mechanism as a function of bolometric luminosity, finding evidence for a strong connection between significant black hole growth events and major galaxy mergers from z~ 0 to z~ 3, while less spectacular but longer accretion episodes are most likely due to other (stochastic) processes. AGN activity triggered by major galaxies is responsible for ~60% of the total black hole growth. Finally, we constrain the total accreted mass density in supermassive black holes at z > 6, inferred via the upper limit derived from the integrated X-ray emission from a sample of photometrically selected galaxy candidates. We estimate an accreted mass density <1000 M⊙Mpc-3 at z~ 6, significantly lower than the previous predictions from some existing models of early black hole growth and earlier prior observations.

  15. The AGN Population and the Cosmic X-ray Background

    NASA Astrophysics Data System (ADS)

    Treister, Ezequiel; Urry, C. Meg; Schawinski, Kevin

    2015-08-01

    In order to fully understand galaxy formation we need to know when in the cosmic history are supermassive black holes (SMBHs) growing more intensively, in what type of galaxies this growth is happening and what fraction of these sources are invisible at most wavelengths due to obscuration. Active Galactic Nuclei (AGN) population synthesis models that can explain the spectral shape and intensity of the cosmic X-ray background (CXRB) indicate that most of the SMBH growth occurs in moderate-luminosity (Lx~1044 erg/s) sources (Seyfert-type AGN), at z~0.5-1 and in heavily obscured but Compton-thin, NH~1023 cm-2, systems.However, this is not the complete history, as a large fraction of black hole growth does not emit significantly in X-rays either due to obscuration, intrinsic low luminosities or large distances. Using a combination of X-ray stacking and multi wavelength selection techniques we constrain the amount of black hole accretion as a function of cosmic history, from z~0 to z~6. The integrated intensity at high energies indicates that a significant fraction of the total black hole growth, 22%, occurs in heavily-obscured systems that are not individually detected in even the deepest X-ray observations.We finally investigate the AGN triggering mechanism as a function of bolometric luminosity, finding evidence for a strong connection between significant black hole growth events and major galaxy mergers from z~0 to z~3, while less spectacular but longer accretion episodes are most likely due to other (stochastic) processes. AGN activity triggered by major galaxies is responsible for ~60% of the total black hole growth.

  16. Cadenced IRAC Monitoring of Infrared-Variable AGNs, Part II

    NASA Astrophysics Data System (ADS)

    Ashby, Matthew; Fouesneau, Morgan; Hora, Joseph; Krick, Jessica; Smith, Howard; Surace, Jason

    2008-03-01

    We have analyzed IRAC imaging data from all 97 Spitzer visits to a very well-studied field, the IRAC Dark Calibration Field (IRAC-CF) near the north ecliptic pole. With this extensive dataset we have already identified a unique sample of 30 IR-variable galaxies which we are now working to characterize with respect to variability amplitudes and timescales, panchromatic SEDs, and host morphologies, among other quantities. Unfortunately, the continual change in spacecraft roll angle means that our sources are typically observed for at most six months at a time by each IRAC FOV in succession -- in other words, the visibility windows are exactly out of phase. Thus the existing data, despite the fact that they extend over more than four years, present large, unavoidable gaps that frustrate the time-delay analysis we wish to perform on exactly the timescales known to be common in active galaxies. This has only changed beginning in 2007 July: since that time cadenced IRAC observations have been carried out in synchrony with the IRAC-CF dark-calibration observations as part of our approved Cycle-4 program (PID 40553). Here we are proposing to continue this successful AGN monitoring campaign until the end of the cryogenic mission. The resulting timelines (covering 1500 days thus far and expected to run ultimately to some 2200+ days), will be a unique legacy of the Spitzer mission. This dataset, especially for the sizable, unbiased AGN sample we now have, holds unique promise for measuring the colors and temperatures of IR-varying AGN, and will have much to say about the underlying physical models of the infrared AGN emission. Accordingly we ask for just 8 h to gather IRAC photometry in the temporal gaps that would otherwise accrue in Cycle 5.

  17. [Acute kidney injury in children].

    PubMed

    Amira-Peco-Antić; Paripović, Dusan

    2014-01-01

    Acute kidney injury (AKI) is a clinical condition considered to be the consequence of a sudden decrease (> 25%) or discontinuation of renal function. The term AKI is used instead of the previous term acute renal failure, because it has been demonstrated that even minor renal lesions may cause far-reaching consequences on human health. Contemporary classifications of AKI (RIFLE and AKIN) are based on the change of serum creatinine and urinary output. In the developed countries, AKI is most often caused by renal ischemia, nephrotoxins and sepsis, rather than a (primary) diffuse renal disease, such as glomerulonephritis, interstitial nephritis, renovascular disorder and thrombotic microangiopathy. The main risk factors for hospital AKI are mechanical ventilation, use of vasoactive drugs, stem cell transplantation and diuretic-resistant hypervolemia. Prerenal and parenchymal AKI (previously known as acute tubular necrosis) jointly account for 2/3 of all AKI causes. Diuresis and serum creatinine concentration are not early diagnostic markers of AKI. Potential early biomarkers of AKI are neutrophil gelatinase-associated lipocalin (NGAL), cystatin C, kidney injury molecule-1 (KIM-1), interleukins 6, 8 and 18, and liver-type fatty acid-binding protein (L-FABP). Early detection of kidney impairment, before the increase of serum creatinine, is important for timely initiated therapy and recovery. The goal of AKI treatment is to normalize the fluid and electrolyte status, as well as the correction of acidosis and blood pressure. Since a severe fluid overload resistant to diuretics and inotropic agents is associated with a poor outcome, the initiation of dialysis should not be delayed. The mortality rate of AKI is highest in critically ill children with multiple organ failure and hemodynamically unstable patients. PMID:25033598

  18. Clustering of ROSAT All-Sky Survey AGNs Through Cross-Correlation Functions

    NASA Astrophysics Data System (ADS)

    Krumpe, Mirko; Miyaji, Takamitsu; Coil, Alison

    2010-07-01

    We investigate the clustering propertiesof ~1550 low-redshift broad-line AGNs detected in the ROSAT All-Sky Survey (RASS) through a cross-correlation function (CCF) with ~46000 Luminous Red Galaxies (LRGs) in the Sloan Digital Sky Survey (SDSS). Using this approach, we avoid small-number statistics and systematic errors caused by the variation of the Galactic absorption compared to a direct measurement of the AGN auto-correlation function (ACF). We compute the ACF of low-z RASS-AGN based on the CCF for the total X-ray sample ( = 0.25) and found a correlation length of r0 = 4.3-0.4+0.4 h-1 Mpc. Furthermore, we discovered an X-ray luminosity dependence of the clustering signal, i.e. high luminosity AGN cluster stronger than low luminosity AGN. We have also applied a Halo Occupation Distribution (HOD) model directly to our AGN-LRG CCF.

  19. Suzaku Observations of AGN and Synergy with GLAST

    SciTech Connect

    Kataoka, Jun; Takahashi, Tad; Madejski, Greg; /KIPAC, Menlo Park

    2007-10-29

    In next five years, dramatic progress is anticipated for the AGN studies, as we have two important missions to observe celestial sources in the high energy regime: GLAST and Suzaku. Suzaku is the 5th Japanese X-ray astronomy satellite which was successfully launched in July 2005. It carries four X-ray sensitive imaging CCD cameras (0.2-12 keV) located in the focal planes of X-ray telescope, and a non-imaging, collimated hard X-ray detector, which extends the bandpass of the observatory to include the 10-600 keV range. Simultaneous monitoring observations by the two instruments (GLAST and Suzaku) will be particularly valuable for variable radio-loud AGN, allowing the cross-correlations of time series as well as detailed modeling of the spectral evolution between the X-ray and gamma-ray energy bands. In this paper, we show early highlights from Suzaku observations of radio-loud AGNs, and discuss what we can do with GLAST in forthcoming years.

  20. Probing the central parsecs of AGN using Faraday Rotation

    NASA Astrophysics Data System (ADS)

    Zavala, R. T.; Taylor, G. B.

    2002-05-01

    A broad frequency range and low instrumental polarization makes the Very Long Baseline Array (VLBA) an ideal instrument for studying polarimetry at sub-milliarcsecond resolution. To take advantage of these unique capabilities we have conducted a multi-frequency polarization survey of 40 radio-loud AGN (Quasars, BL Lacs, and radio galaxies). Our aim is to use Faraday Rotation Measures (RMs) as a probe of the central 1-50 parsecs of these objects. The RM is produced by the line of sight magnetic field weighted by the electron density. Using the electron density established through spectral line diagnostics a magnetic field strength and topology can be estimated within a few parsecs of the central engines of these AGN. The observations for the survey are complete, and we present the first results for 8 quasars, 5 BL Lacs, and 4 radio galaxies. The magnitudes for the RMs range from several thousand rad m-2 in the quasars and radio galaxies to a few hundred rad m-2 in the BL Lac objects. These values are in agreement with the basic ideas of the unified model for AGN. We also observe variations in the RM on small spatial (< ~ 1 pc) in radio galaxies and quasars; and short time scales ( ~ 6 months) in the quasars 3C 273 and 3C 279. R.T.Z. gratefully acknowledges support from a pre-doctoral research appointment at NRAO and from the New Mexico Alliance for Graduate Education and the Professiorate through NSF grant HRD-0086701.

  1. Doppler disc tomography applied to low-mass AGN spin

    NASA Astrophysics Data System (ADS)

    Middleton, Matthew J.; Ingram, Adam R.

    2015-01-01

    Doppler tomography can provide a powerful means of determining black hole spin when our view to the central regions are revealed and obscured by optically thick orbiting material, and can provide an independent estimate that does not suffer as many degeneracies as traditional methods. For low-mass active galactic nuclei (AGN), time-dependent obscuration is expected to leave a signature in the changing spectrum of the disc emission which extends into the soft X-ray bandpass. We create a spectral model incorporating Doppler tomography and apply it to the case of the low-mass (8 × 105 M⊙) AGN, RX J1301.9+2747 which shows unusual timing properties in the form of short-lived flares that we argue are best explained by the orbit of a window through an optically thick wind. Modelling the phase-resolved spectrum over the course of the highest data quality flare indicates a very low spin even when we relax our constraints. This is the lowest mass AGN for which a spin has been measured and the first via this technique. We note that, as the mass and spin are very low, this appears to favour supermassive black hole (SMBH) growth by chaotic rather than constant accretion.

  2. Modeling AGN outbursts from supermassive black hole binaries

    NASA Astrophysics Data System (ADS)

    Tanaka, T.

    2012-12-01

    When galaxies merge to assemble more massive galaxies, their nuclear supermassive black holes (SMBHs) should form bound binaries. As these interact with their stellar and gaseous environments, they will become increasingly compact, culminating in inspiral and coalescence through the emission of gravitational radiation. Because galaxy mergers and interactions are also thought to fuel star formation and nuclear black hole activity, it is plausible that such binaries would lie in gas-rich environments and power active galactic nuclei (AGN). The primary difference is that these binaries have gravitational potentials that vary - through their orbital motion as well as their orbital evolution - on humanly tractable timescales, and are thus excellent candidates to give rise to coherent AGN variability in the form of outbursts and recurrent transients. Although such electromagnetic signatures would be ideally observed concomitantly with the binary's gravitational-wave signatures, they are also likely to be discovered serendipitously in wide-field, high-cadence surveys; some may even be confused for stellar tidal disruption events. I discuss several types of possible "smoking gun" AGN signatures caused by the peculiar geometry predicted for accretion disks around SMBH binaries.

  3. Clustering, Cosmology and a New Era of Black Hole Demographics: The Conditional Luminosity Function of AGNs

    NASA Astrophysics Data System (ADS)

    Ballantyne, David R.

    2016-04-01

    Deep X-ray surveys have provided a comprehensive and largely unbiased view of AGN evolution stretching back to z˜5. However, it has been challenging to use the survey results to connect this evolution to the cosmological environment that AGNs inhabit. Exploring this connection will be crucial to understanding the triggering mechanisms of AGNs and how these processes manifest in observations at all wavelengths. In anticipation of upcoming wide-field X-ray surveys that will allow quantitative analysis of AGN environments, we present a method to observationally constrain the Conditional Luminosity Function (CLF) of AGNs at a specific z. Once measured, the CLF allows the calculation of the AGN bias, mean dark matter halo mass, AGN lifetime, halo occupation number, and AGN correlation function - all as a function of luminosity. The CLF can be constrained using a measurement of the X-ray luminosity function and the correlation length at different luminosities. The method is demonstrated at z ≈0 and 0.9, and clear luminosity dependence in the AGN bias and mean halo mass is predicted at both z. The results support the idea that there are at least two different modes of AGN triggering: one, at high luminosity, that only occurs in high mass, highly biased haloes, and one that can occur over a wide range of halo masses and leads to luminosities that are correlated with halo mass. This latter mode dominates at z<0.9. The CLFs for Type 2 and Type 1 AGNs are also constrained at z ≈0, and we find evidence that unobscured quasars are more likely to be found in higher mass halos than obscured quasars. Thus, the AGN unification model seems to fail at quasar luminosities.

  4. X-Ray Absorption, Nuclear Infrared Emission, and Dust Covering Factors of AGNs: Testing Unification Schemes

    NASA Astrophysics Data System (ADS)

    Mateos, S.; Carrera, F. J.; Alonso-Herrero, A.; Hernán-Caballero, A.; Barcons, X.; Asensio Ramos, A.; Watson, M. G.; Blain, A.; Caccianiga, A.; Ballo, L.; Braito, V.; Ramos Almeida, C.

    2016-03-01

    We present the distributions of the geometrical covering factors of the dusty tori (f2) of active galactic nuclei (AGNs) using an X-ray selected complete sample of 227 AGNs drawn from the Bright Ultra-hard XMM-Newton Survey. The AGNs have z from 0.05 to 1.7, 2-10 keV luminosities between 1042 and 1046 erg s-1, and Compton-thin X-ray absorption. Employing data from UKIDSS, 2MASS, and the Wide-field Infrared Survey Explorer in a previous work, we determined the rest-frame 1-20 μm continuum emission from the torus, which we model here with the clumpy torus models of Nenkova et al. Optically classified type 1 and type 2 AGNs are intrinsically different, with type 2 AGNs having, on average, tori with higher f2 than type 1 AGNs. Nevertheless, ˜20% of type 1 AGNs have tori with large covering factors, while ˜23%-28% of type 2 AGNs have tori with small covering factors. Low f2 are preferred at high AGN luminosities, as postulated by simple receding torus models, although for type 2 AGNs the effect is certainly small. f2 increases with the X-ray column density, which implies that dust extinction and X-ray absorption take place in material that share an overall geometry and most likely belong to the same structure, the putative torus. Based on our results, the viewing angle, AGN luminosity, and also f2 determine the optical appearance of an AGN and control the shape of the rest-frame ˜1-20 μm nuclear continuum emission. Thus, the torus geometrical covering factor is a key ingredient of unification schemes.

  5. Hepatitis C eradication and improvement of cryoglobulinemia-associated rash and membranoproliferative glomerulonephritis with interferon and ribavirin after kidney transplantation

    PubMed Central

    Zeman, Marilyn; Campbell, Patricia; Bain, Vincent G

    2006-01-01

    Postrenal transplant hepatitis C is increasing in frequency due to the high prevalence of hepatitis C among patients with renal failure. Despite this, there is still no standard hepatitis C treatment available for renal transplanted recipients. Combination antiviral hepatitis C therapy, the standard of care in the nontransplant population, is generally avoided because of documented renal graft rejection secondary to interferon treatment. A case of a male patient with postrenal transplant hepatitis C, which was associated with cryoglobulinemia and glomerulonephritis of the graft, is presented. He was treated with standard interferon with ribavirin. Sustained viral clearance was achieved despite ongoing evidence of cryoglobulinemia. Renal function, which had been deteriorating before treatment, improved as evidenced by the stabilization of serum creatinine and marked improvement of proteinuria. In conclusion, in selected patients, combination antiviral therapy may still be a viable option postrenal transplant. PMID:16779461

  6. Cycling of the powerful AGN in MS 0735.6+7421 and the duty cycle of radio AGN in clusters

    NASA Astrophysics Data System (ADS)

    Vantyghem, A. N.; McNamara, B. R.; Russell, H. R.; Main, R. A.; Nulsen, P. E. J.; Wise, M. W.; Hoekstra, H.; Gitti, M.

    2014-08-01

    We present an analysis of deep Chandra X-ray observations of the galaxy cluster MS 0735.6+7421, which hosts the most energetic radio active galactic nucleus (AGN) known. Our analysis has revealed two cavities in its hot atmosphere with diameters of 200-240 kpc. The total cavity enthalpy, mean age, and mean jet power are 9 × 1061 erg, 1.6 × 108 yr, and 1.7 × 1046 erg s-1, respectively. The cavities are surrounded by nearly continuous temperature and surface brightness discontinuities associated with an elliptical shock front of Mach number 1.26 (1.17-1.30) and age of 1.1 × 108 yr. The shock has injected at least 4 × 1061 erg into the hot atmosphere at a rate of 1.1 × 1046 erg s-1. A second pair of cavities and possibly a second shock front are located along the radio jets, indicating that the AGN power has declined by a factor of 30 over the past 100 Myr. The multiphase atmosphere surrounding the central galaxy is cooling at a rate of 40 M⊙yr-1, but does not fuel star formation at an appreciable rate. In addition to heating, entrainment in the radio jet may be depleting the nucleus of fuel and preventing gas from condensing out of the intracluster medium. Finally, we examine the mean time intervals between AGN outbursts in systems with multiple generations of X-ray cavities. We find that, like MS0735, their AGN rejuvenate on a time-scale that is approximately 1/3 of their mean central cooling time-scales, indicating that jet heating is outpacing cooling in these systems.

  7. Highly variable AGN from the XMM-Newton slew survey

    NASA Astrophysics Data System (ADS)

    Strotjohann, N. L.; Saxton, R. D.; Starling, R. L. C.; Esquej, P.; Read, A. M.; Evans, P. A.; Miniutti, G.

    2016-07-01

    Aims: We investigate the properties of a variability-selected complete sample of active galactic nuclei (AGN) in order to identify the mechanisms which cause large amplitude X-ray variability on timescales of years. Methods: A complete sample of 24 sources was constructed, from AGN which changed their soft X-ray luminosity by more than one order of magnitude over 5-20 years between ROSAT observations and the XMM-Newton slew survey. Follow-up observations were obtained with the Swift satellite. We analysed the spectra of these AGN at the Swift and XMM observation epochs, where six sources had continued to display extreme variability. Multiwavelength data are used to calculate black hole masses and the relative X-ray brightness αOX. Results: After removal of two probable spurious sources, we find that the sample has global properties which differ little from a non-varying control sample drawn from the wider XMM-slew/ROSAT/Veron sample of all secure AGN detections. A wide range of AGN types are represented in the varying sample. The black hole mass distributions for the varying and non-varying sample are not significantly different. This suggests that long timescale variability is not strongly affected by black hole mass. There is marginal evidence that the variable sources have a lower redshift (2σ) and X-ray luminosity (1.7σ). Apart from two radio-loud sources, the sample sources have normal optical-X-ray ratios (αOX) when at their peak but are X-ray weak during their lowest flux measurements. Conclusions: Drawing on our results and other studies, we are able to identify a variety of variability mechanisms at play: tidal disruption events, jet activity, changes in absorption, thermal emission from the inner accretion disc, and variable accretion disc reflection. Little evidence for strong absorption is seen in the majority of the sample and single-component absorption can be excluded as the mechanism for most sources.

  8. AGN Feedback in Overdense Environments at z=2.23

    NASA Astrophysics Data System (ADS)

    Lucy, Adrian B.; Lehmer, B.; Alexander, D. M.; Best, P.; Geach, J.; Harrison, C. M.; Hornschemeier, A. E.; Matsuda, Y.; Mullaney, J.; Smail, I.; Sobral, D.

    2013-01-01

    We present results from a ≈100 ks Chandra observation of the 2QZ Cluster 1004+00 galaxy overdensity at z=2.23. This 2QZ Clus structure was first identified as an overdensity of four optically-selected quasars; that sample was subsequently found to overlap with an overdensity of 22 Hα-emitting galaxies (HAEs) identified through narrow and broad band near-infrared imaging by Matsuda et al. (2011). In addition to the preselected quasars in 2QZ Clus, our Chandra observation reveals that a further three HAEs are X-ray sources, all characterized by X-ray luminosities and spectral slopes consistent with unobscured active galactic nuclei (AGN). In total, we find that ≈30% of HAEs in our observed region of 2QZ Clus are AGN. This AGN fraction is high compared to AGN fractions among HAEs in the Chandra-COSMOS field (C-COSMOS), and if this enhancement is purely a result of the quasar selection bias of our sample, we estimate that such activity is rare at this redshift. Hα is a tracer of star formation, so 2QZ Clus is well suited to the investigation of the coeval growth of supermassive black holes and their host galaxies in the precursors to rich local clusters. Moreover, we have an ideal control sample in C-COSMOS; this survey contains a large sample of HAEs classified identically using infrared imaging, but without any selection of quasars. We calculate AGN fraction as a function of galaxy overdensity in C-COSMOS, and perform stacking analyses of Chandra and 250μ Herschel SPIRE data to obtain mean black hole accretion rates dMBH/dt and star formation rates SFR. Preliminary results indicate that dMBH/dt and its ratio to SFR are significantly elevated in 2QZ Clus compared to similarly overdense regions of C-COSMOS. We discuss these relations in the context of theoretical models describing the emergence of the MBH/Mgal relation of the local Universe.

  9. Hydrodynamic models of AGN feedback in cooling core clusters

    NASA Astrophysics Data System (ADS)

    Vernaleo, John C.

    X-ray observations show that the Intra Cluster Medium (ICM) in many galaxy clusters is cooling at a rapid rate, often to the point that it should have radiated away all of its energy in less than the age of the cluster. There is however a very clear lack of enough cool end products of this gas in the centers of the clusters. Energetic arguments indicate that Active Galactic Nuclei (AGN) should be capable of heating the inner regions of clusters enough to offset the radiative cooling; truncating massive galaxy formation and solving the cooling flow problem. We present three sets of high resolution, ideal hydrodynamic simulations with the ZEUS code to test this AGN heating paradigm. For the first set of simulations, we study the dependence of the interaction between the AGN jets and the ICM on the parameters of the jets themselves. We present a parameter survey of two-dimensional (axisymmetric) models of back-to-back jets injected into a cluster atmosphere. We follow the passive evolution of the resulting structures. These simulations fall into roughly two classes, cocoon-bounded and non-cocoon bounded. We find that the cocoon-bounded sources inject significantly more entropy into the core regions of the ICM atmosphere, even though the efficiency with which the energy is thermalized is independent of the morphological class. In all cases, a large fraction of the energy injected by the jet ends up as gravitational potential energy due to the expansion of the atmosphere. For the second set, we present three-dimensional simulations of jetted AGN that act in response to cooling-mediated accretion of an ICM atmosphere. We find that our models are incapable of producing a long term balance of heating and cooling; catastrophic cooling can be delayed by the jet action but inevitably takes hold. At the heart of the failure of these models is the formation of a low density channel through which the jet can freely flow, carrying its energy out of the cooling core. Finally, we

  10. Three years of Swift/BAT Survey of AGN: Reconciling Theory and Observations?

    SciTech Connect

    Burlon, D.; Ajello, M.; Greiner, J.; Comastri, A.; Merloni, A.; Gehrels, N.; /NASA, Goddard

    2011-02-07

    It is well accepted that unabsorbed as well as absorbed AGN are needed to explain the nature and the shape of the Cosmic X-ray background, even if the fraction of highly absorbed objects (dubbed Compton-thick sources) substantially still escapes detection. We derive and analyze the absorption distribution using a complete sample of AGN detected by Swift-BAT in the first three years of the survey. The fraction of Compton-thick AGN represents only 4.6% of the total AGN population detected by Swift-BAT. However, we show that once corrected for the bias against the detection of very absorbed sources the real intrinsic fraction of Compton-thick AGN is 20{sub -6}{sup +9}%. We proved for the first time (also in the BAT band) that the anti-correlation of the fraction of absorbed AGN and luminosity it tightly connected to the different behavior of the luminosity functions (XLFs) of absorbed and unabsorbed AGN. This points towards a difference between the two subsamples of objects with absorbed AGN being, on average, intrinsically less luminous than unobscured ones. Moreover the XLFs show that the fraction of obscured AGN might also decrease at very low luminosity. This can be successfully interpreted in the framework of a disk cloud outflow scenario as the disappearance of the obscuring region below a critical luminosity. Our results are discussed in the framework of population synthesis models and the origin of the Cosmic X-ray Background.

  11. VizieR Online Data Catalog: Gamma-ray AGN type determination (Hassan+, 2013)

    NASA Astrophysics Data System (ADS)

    Hassan, T.; Mirabal, N.; Contreras, J. L.; Oya, I.

    2013-11-01

    In this paper, we employ Support Vector Machines (SVMs) and Random Forest (RF) that embody two of the most robust supervised learning algorithms available today. We are interested in building classifiers that can distinguish between two AGN classes: BL Lacs and FSRQs. In the 2FGL, there is a total set of 1074 identified/associated AGN objects with the following labels: 'bzb' (BL Lacs), 'bzq' (FSRQs), 'agn' (other non-blazar AGN) and 'agu' (active galaxies of uncertain type). From this global set, we group the identified/associated blazars ('bzb' and 'bzq' labels) as the training/testing set of our algorithms. (2 data files).

  12. Cooling, AGN Feedback and Star Formation in Cool-Core Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Li, Yuan; Bryan, Greg; Ruszkowski, Mateusz

    2015-01-01

    The feedback from active galactic nuclei (AGNs) is widely considered to be the major heating source in cool-core galaxy clusters to prevent a classical cooling flow. Numerical simulations with AGN feedback have successfully suppressed radiative cooling, but generally fail to reproduce the right amount of cold gas and the expected cyclical AGN activities. We perform adaptive mesh simulations including both momentum-driven AGN feedback and star formation to study the interplay between cooling, AGN heating and star formation over ~ 6.5 Gyr time in an isolated cool-core cluster. Cold clumps first cool out of the ICM due to the non-liner perturbation driven by the AGN jets. These cold clumps feed both star formation and the supermassive black hole (SMBH), triggering an AGN outburst which increases the entropy of the ICM and reduces its cooling rate. Within 1-2 Gyr, star formation completely consumes the cold gas, which leads to a brief shutoff of the AGN. The ICM quickly cools and develops multiphase gas again, followed by another cycle of star formation/AGN outburst. Within 6.5 Gyr, we observe three such cycles. The average star formation rate is ~40 solar mass/yr. The black hole accretion rate shows a large scatter, but the average correlates well with the star formation rate and is roughly one order of magnitude lower.

  13. The sharpest view of the local AGN population at mid-infrared wavelengths

    NASA Astrophysics Data System (ADS)

    Asmus, Daniel; Hönig, Sebastian F.; Gandhi, Poshak; Smette, Alain; Duschl, Wolfgang J.

    2014-07-01

    We present the largest mid-infrared (MIR) atlas of active galactic nuclei at sub-arcsec spatial scales containing 253 objects with a median redshift of 0.016. It comprises all available ground-based high-angular resolution MIR observations performed to date with 8-meter class telescopes and includes 895 photometric measurements. All types of AGN are present in the atlas, which also includes 80 per cent of the 9-month BAT AGN sample. Therefore, this atlas and its subsamples are very well-suited for AGN unification studies. A first application of the atlas is the extension of the MIR-X-ray luminosity correlation for AGN.

  14. Acute Bronchitis

    MedlinePlus

    ... or though physical contact (for example, on unwashed hands). Being exposed to tobacco smoke, air pollution, dusts, vapors, and fumes can also cause acute bronchitis. Less often, bacteria can also cause acute bronchitis. To diagnose acute ...

  15. Cystitis - acute

    MedlinePlus

    Uncomplicated urinary tract infection; UTI - acute; Acute bladder infection; Acute bacterial cystitis ... control. Menopause also increases the risk for a urinary tract infection. The following also increase your chances of having ...

  16. Long-term graft outcomes and patient survival are lower posttransplant in patients with a primary renal diagnosis of glomerulonephritis.

    PubMed

    Pruthi, Rishi; McClure, Mark; Casula, Anna; Roderick, Paul J; Fogarty, Damian; Harber, Mark; Ravanan, Rommel

    2016-04-01

    Glomerulonephritis (GN) is the primary diagnosis in 20% to 40% of patients receiving a renal transplant. Here we studied patient survival and graft outcomes in patients with GN transplanted in the UK. UK Renal Registry data were used to analyze patient survival and graft failure in incident transplant patients between 1997 to 2009 who had a diagnosis of primary GN, in comparison to patients transplanted with adult polycystic kidney disease (APKD) or diabetes. Multivariable regression analysis adjusted for age, sex, donor type, ethnicity, donor age, time on dialysis, human leukocyte antigen mismatch, cold ischemic time, and graft failure (for patient survival). Patients were followed up through December 2012. Of 4750 patients analyzed, 2975 had GN and 1775 APKD. Graft failure was significantly higher in membranoproliferative glomerulonephritis (MPGN) type II (hazard ratio: 3.5, confidence interval: 1.9-6.6), focal segmental glomerulosclerosis (2.4, 1.8-3.2), MPGN type I (2.3, 1.6-3.3), membranous nephropathy (2.0, 1.4-2.9), and IgA nephropathy (1.6, 1.3-2.0) compared to APKD. Survival was significantly reduced in patients with MPGN type II (4.7, 2.0-10.8), and those with lupus nephritis (1.8, 1.1-2.9). Overall graft failure for patients with GN was similar to those with diabetes. Thus, in comparison to outcomes in APKD, graft survival is significantly lower in most GNs, with variation in outcomes between different GNs. This information should assist in pretransplant counseling of patients. Further study is required to understand the reduced survival seen in lupus nephritis and MPGN type II, and to improve overall graft outcomes. PMID:26924061

  17. Linking X-ray AGN with dark matter halos: a model compatible with AGN luminosity function and large-scale clustering properties

    NASA Astrophysics Data System (ADS)

    Hütsi, Gert; Gilfanov, Marat; Sunyaev, Rashid

    2014-01-01

    Aims: Our goal is to find a minimalistic model that describes the luminosity function and large-scale clustering bias of X-ray-selected active galactic nuclei in the general framework of the concordance ΛCDM model. Methods: We assume that a simple population-averaged scaling relation between the AGN X-ray luminosity LX and the host dark matter halo mass Mh exists. With such a relation, the AGN X-ray luminosity function can be computed from the halo mass function. Using the concordance ΛCDM halo mass function for the latter, we obtain the Mh - LX relation required to match the redshift-dependent AGN X-ray luminosity function known from X-ray observations. Results: We find that with a simple power-law-scaling Mh ∝ LΓ(z), our model can successfully reproduce the observed X-ray luminosity function. Furthermore, we automatically obtain predictions for the large-scale AGN clustering amplitudes and their dependence on the luminosity and redshift, which seem to be compatible with AGN clustering measurements. Our model also includes the redshift-dependent AGN duty cycle, which peaks at the redshift z ≃ 1, and its peak value is consistent with unity, suggesting that on average there is no more than one AGN per dark matter halo. For a typical X-ray-selected AGN at z ~ 1, our best-fit Mh - LX scaling implies low Eddington ratio LX/LEdd ~ 10-4 - 10-3 (2-10 keV band, no bolometric correction applied) and correspondingly high mass-growth e-folding times, suggesting that typical X-ray AGN are dominantly fueled via relatively inefficient "hot-halo" accretion mode.

  18. VizieR Online Data Catalog: ASCA AGN optical identifications (Akiyama+, 2003)

    NASA Astrophysics Data System (ADS)

    Akiyama, M.; Ueda, Y.; Ohta, K.; Takahashi, T.; Yamada, T.

    2003-10-01

    We present the results of optical spectroscopic identifications of a bright subsample of 2-10keV hard X-ray-selected sources from the ASCA Medium Sensitivity Survey in the northern sky (AMSSn). The flux limit of the subsample is 3x10-13erg/s/cm2 in the 2-10keV band. All but one of the 87 hard X-ray-selected sources are optically identified, with AGNs (including broad-line AGNs, narrow-line AGNs, and three BL Lac objects), seven clusters of galaxies, and one galactic star. It is the largest complete sample of hard X-ray-selected AGNs at the bright flux limit. Amounts of absorption to their nuclei are estimated to be hydrogen column densities (NH) of up to 3x1023cm-2 from their X-ray spectra. Optical properties of X-ray absorbed AGNs with NH>1x1022cm-2 indicate the effects of dust absorption: at redshifts z<0.6, AGNs without broad H{beta} emission lines have significantly larger NH-values than AGNs with broad H{beta} emission lines. At z>0.6, the X-ray absorbed AGNs have a large hard X-ray to optical flux ratio (logf2-10keV/fR>+1). However, three X-ray absorbed z>0.6 AGNs show strong broad lines. In combination with hard X-ray-selected AGN samples from the ASCA Large Sky Survey, the ASCA Deep Survey in the Lockman Hole, and Chandra Deep Field North, the luminosity distributions of absorbed (NH>1x1022cm-2) and less-absorbed (NH<1x1022cm-2) AGNs are compared. (4 data files).

  19. AGN are cooler than you think: the intrinsic far-IR emission from QSOs

    NASA Astrophysics Data System (ADS)

    Symeonidis, M.; Giblin, B. M.; Page, M. J.; Pearson, C.; Bendo, G.; Seymour, N.; Oliver, S. J.

    2016-06-01

    We present an intrinsic AGN spectral energy distribution (SED) extending from the optical to the submm, derived with a sample of unobscured, optically luminous (νLν,5100 > 1043.5 erg s-1) QSOs at z < 0.18 from the Palomar Green survey. The intrinsic AGN SED was computed by removing the contribution from stars using the 11.3 μm polycyclic aromatic hydrocarbon (PAH) feature in the QSOs' mid-IR spectra; the 1σ uncertainty on the SED ranges between 12 and 45 per cent as a function of wavelength and is a combination of PAH flux measurement errors and the uncertainties related to the conversion between PAH luminosity and star-forming luminosity. Longwards of 20 μm, the shape of the intrinsic AGN SED is independent of the AGN power indicating that our template should be applicable to all systems hosting luminous AGN (νLν, 5100 or L_X(2-10 keV) ≳ 1043.5 erg s-1). We note that for our sample of luminous QSOs, the average AGN emission is at least as high as, and mostly higher than, the total stellar powered emission at all wavelengths from the optical to the submm. This implies that in many galaxies hosting powerful AGN, there is no `safe' broad-band photometric observation (at λ < 1000 μm) which can be used in calculating star formation rates without subtracting the AGN contribution. Roughly, the AGN contribution may be ignored only if the intrinsic AGN luminosity at 5100 AA is at least a factor of 4 smaller than the total infrared luminosity (LIR, 8-1000 μm) of the galaxy. Finally, we examine the implication of our work in statistical studies of star formation in AGN host galaxies.

  20. Are Compton-thick AGNs the Missing Link between Mergers and Black Hole Growth?

    NASA Astrophysics Data System (ADS)

    Kocevski, Dale D.; Brightman, Murray; Nandra, Kirpal; Koekemoer, Anton M.; Salvato, Mara; Aird, James; Bell, Eric F.; Hsu, Li-Ting; Kartaltepe, Jeyhan S.; Koo, David C.; Lotz, Jennifer M.; McIntosh, Daniel H.; Mozena, Mark; Rosario, David; Trump, Jonathan R.

    2015-12-01

    We examine the host morphologies of heavily obscured active galactic nuclei (AGNs) at z∼ 1 to test whether obscured super-massive black hole growth at this epoch is preferentially linked to galaxy mergers. Our sample consists of 154 obscured AGNs with {N}{{H}}\\gt {10}23.5 {{cm}}-2 and z\\lt 1.5. Using visual classifications, we compare the morphologies of these AGNs to control samples of moderately obscured (1022 cm{}-2\\lt {N}{{H}}\\lt {10}23.5 {{cm}}-2) and unobscured ({N}{{H}}\\lt {10}22 {{cm}}-2) AGN. These control AGNs have similar redshifts and intrinsic X-ray luminosities to our heavily obscured AGN. We find that heavily obscured AGNs are twice as likely to be hosted by late-type galaxies relative to unobscured AGNs ({65.3}-4.6+4.1% versus {34.5}-2.7+2.9%) and three times as likely to exhibit merger or interaction signatures ({21.5}-3.3+4.2% versus {7.8}-1.3+1.9%). The increased merger fraction is significant at the 3.8σ level. If we exclude all point sources and consider only extended hosts, we find that the correlation between the merger fraction and obscuration is still evident, although at a reduced statistical significance (2.5σ ). The fact that we observe a different disk/spheroid fraction versus obscuration indicates that the viewing angle cannot be the only thing differentiating our three AGN samples, as a simple unification model would suggest. The increased fraction of disturbed morphologies with obscuration supports an evolutionary scenario, in which Compton-thick AGNs are a distinct phase of obscured super-massive black hole (SMBH) growth following a merger/interaction event. Our findings also suggest that some of the merger-triggered SMBH growth predicted by recent AGN fueling models may be hidden among the heavily obscured, Compton-thick population.

  1. Relativistic HD and MHD modelling for AGN jets

    NASA Astrophysics Data System (ADS)

    Keppens, R.; Porth, O.; Monceau-Baroux, R.; Walg, S.

    2013-12-01

    Relativistic hydro and magnetohydrodynamics (MHD) provide a continuum fluid description for plasma dynamics characterized by shock-dominated flows approaching the speed of light. Significant progress in its numerical modelling emerged in the last two decades; we highlight selected examples of modern grid-adaptive, massively parallel simulations realized by our open-source software MPI-AMRVAC (Keppens et al 2012 J. Comput. Phys. 231 718). Hydrodynamical models quantify how energy transfer from active galactic nuclei (AGN) jets to their surrounding interstellar/intergalactic medium (ISM/IGM) gets mediated through shocks and various fluid instability mechanisms (Monceau-Baroux et al 2012 Astron. Astrophys. 545 A62). With jet parameters representative for Fanaroff-Riley type-II jets with finite opening angles, we can quantify the ISM volumes affected by jet injection and distinguish the roles of mixing versus shock-heating in cocoon regions. This provides insight in energy feedback by AGN jets, usually incorporated parametrically in cosmological evolution scenarios. We discuss recent axisymmetric studies up to full 3D simulations for precessing relativistic jets, where synthetic radio maps can confront observations. While relativistic hydrodynamic models allow one to better constrain dynamical parameters like the Lorentz factor and density contrast between jets and their surroundings, the role of magnetic fields in AGN jet dynamics and propagation characteristics needs full relativistic MHD treatments. Then, we can demonstrate the collimating properties of an overal helical magnetic field backbone and study differences between poloidal versus toroidal field dominated scenarios (Keppens et al 2008 Astron. Astrophys. 486 663). Full 3D simulations allow one to consider the fate of non-axisymmetric perturbations on relativistic jet propagation from rotating magnetospheres (Porth 2013 Mon. Not. R. Astron. Soc. 429 2482). Self-stabilization mechanisms related to the detailed

  2. The view of AGN-host alignment via reflection spectroscopy

    NASA Astrophysics Data System (ADS)

    Middleton, Matthew J.; Parker, Michael L.; Reynolds, Christopher S.; Fabian, Andrew C.; Lohfink, Anne M.

    2016-04-01

    The fuelling of active galactic nuclei (AGN) - via material propagated through the galactic disc or via minor mergers - is expected to leave an imprint on the alignment of the sub-pc disc relative to the host galaxy's stellar disc. Determining the inclination of the inner disc usually relies on the launching angle of the jet; here instead we use the inclination derived from reflection fits to a sample of AGN. We determine the distorting effect of unmodelled Fe XXV/XXVI features and, via extensive simulations, determine the difference in disc inclination resulting from the use of RELXILL compared to REFLIONX. We compare inner disc inclinations to those for the host galaxy stellar disc derived from the Hubble formula and, via Monte Carlo simulations, find a strong lack of a correlation (at ≫5σ) implying either widespread feeding via mergers if we assume the sample to be homogeneous, or that radiative disc warps are distorting our view of the emission. However, we find that by removing a small (˜1/5) subset of AGN, the remaining sample is consistent with random sampling of an underlying 1:1 correlation (at the 3σ level). A heterogenous sample would likely imply that our view is not dominated by radiative disc warps but instead by different feeding mechanisms with the majority consistent with coplanar accretion (although this may be the result of selection bias), whilst a smaller but not insignificant fraction may have been fuelled by minor mergers in the recent history of the host galaxy.

  3. The AGN Contribution to Galaxy Merger Infrared Luminosities

    NASA Astrophysics Data System (ADS)

    Rosenthal, Lee; Hayward, Christopher C.; Smith, Howard; Ashby, Matthew; Hung, Chao-Ling; Martinez-Galarza, Rafael; Weiner, Aaron; Zezas, Andreas; Lanz, Lauranne

    2015-01-01

    We investigate the contribution of AGN activity to the infrared luminosity of interacting galaxies by analyzing dust radiative transfer calculations of a hydrodynamically simulated merger, created with the code GADGET-2. We focus on emission in the mid-IR to far-IR wavelength ranges, and trace the luminosity density of an interacting gas-rich galaxy pair throughout its evolution. We find that the AGN contribution to IR luminosity is greatest during and immediately after coalescence of the galaxies' central black holes. This period lasts roughly 80 Myr, during which time the increased influx of gas to the center of the merger increases the total luminosity by a factor of a thousand or more due to both increased star formation rate (SFR) and black hole accretion. We compare different interstellar medium models used to describe sub-resolution gas and dust clouds in the radiative transfer calculations by studying the color evolution of our merger in the Herschel Space Observatory photometric filter bands, and compare the results to Herschel observations. We conclude that using infrared luminosity as a simple surrogate for SFR can overestimate the true rate, due to the contribution of AGN or other dust heating mechanisms. This conclusion has an especially significant impact in assessing the star formation activity in high-redshift galaxies for which luminosity (the best measured property) may not accurately measure the SFR, and in cases where the molecular gas content can differ from that of local systems. Further work will extend this analysis to simulations of mergers between late-type galaxies. This work was supported in part by the NSF REU and DOD ASSURE programs under NSF grant no. 1262851, by the Smithsonian Institution and by NASA grant NNX14AJ6IG.

  4. AGN-stimulated cooling of hot gas in elliptical galaxies

    NASA Astrophysics Data System (ADS)

    Valentini, Milena; Brighenti, Fabrizio

    2015-04-01

    We study the impact of relatively weak active galactic nucleus (AGN) feedback on the interstellar medium (ISM) of intermediate and massive elliptical galaxies. We find that the AGN activity, while globally heating the ISM, naturally stimulates some degree of hot gas cooling on scales of several kpc. This process generates the persistent presence of a cold ISM phase, with mass ranging between 104 and ≳ 5 × 107 M⊙, where the latter value is appropriate for group centred, massive galaxies. Widespread cooling occurs where the ratio of cooling to free-fall time before the activation of the AGN feedback satisfies tcool/tff ≲ 70, that is we find a less restrictive threshold than commonly quoted in the literature. This process helps explaining the body of observations of cold gas (both ionized and neutral/molecular) in Ellipticals and, perhaps, the residual star formation detected in many early-type galaxies. The amount and distribution of the off-centre cold gas vary irregularly with time. The cold ISM velocity field is irregular, initially sharing the (outflowing) turbulent hot gas motion. Typical velocity dispersions of the cold gas lie in the range 100-200 km s-1. Freshly generated cold gas often forms a cold outflow and can appear kinematically misaligned with respect to the stars. We also follow the dust evolution in the hot and cold gas. We find that the internally generated cold ISM has a very low dust content, with representative values of the dust-to-gas ratio of 10-4-10-5. Therefore, this cold gas can escape detection in the traditional dust-absorption maps.

  5. A Search for AGN Intra-Day Variability with KVN

    NASA Astrophysics Data System (ADS)

    Lee, Taeseok; Trippe, Sascha; Oh, Junghwan; Byun, Do-Young; Sohn, Bong-Won; Lee, Sang-Sung

    2015-10-01

    Active galactic nuclei (AGN) are known for irregular variability on all time scales, down to intra-day variability with relative variations of a few percent within minutes to hours. On such short timescales, unexplored territory, such as the possible existence of a shortest characteristic time scale of activity and the shape of the high frequency end of AGN power spectra, still exists. We present the results of AGN single-dish fast photometry performed with the Korean VLBI Network (KVN). Observations were done in a "anti-correlated" mode using two antennas, with always at least one antenna pointing at the target. This results in an effective time resolution of less than three minutes. We used all four KVN frequencies, 22, 43, 86, and 129 GHz, in order to trace spectral variability, if any. We were able to derive high-quality light curves for 3C 111, 3C 454.3, and BL Lacertae at 22 and 43 GHz, and for 3C 279 at 86 GHz, between May 2012 and April 2013. We performed a detailed statistical analysis in order to assess the levels of variability and the corresponding upper limits. We found upper limits on flux variability ranging from ∼1.6% to ∼7.6%. The upper limits on the derived brightness temperatures exceed the inverse Compton limit by three to six orders of magnitude. From our results, plus comparison with data obtained by the University of Michigan Radio Astronomy Observatory, we conclude that we have not detected source-intrinsic variability which would have to occur at sub-per cent levels.

  6. Liners and Low Luminosity AGN in the ROSAT Database

    NASA Technical Reports Server (NTRS)

    Elvis, Martin; West, Donald K. (Technical Monitor)

    2003-01-01

    This program has led to a series of papers being written and published in the Astrophysical Journal. Together these papers try to explain major parts of the LINER and low luminosity AGN puzzle. One paper ('Accretion Disk Instabilities, Cold Dark Matter Models, and Their Role in Quasar Evolution', Hatziminaoglou E., Siemiginowska A., & Elvis M., 2001, ApJ, 547, 90) describes an analytical model for the evolution of the quasar luminosity function. By combining the Press-Schechter formalism for the masses of initial structures with the luminosity distribution for a population of single mass black holes given by an unstable accretion disk an almost complete end-to-end physics-based model of quasar evolution is produced. In this model black holes spend 75% of their time in a low accretion state (at L(Edd)). This low state population of black holes is likely to be observed as the LINER and low luminosity AGNs in the local universe. Another paper ('Broad Emission Line Regions in AGN: the Link with the Accretion Power', Nicastro F., 2000, ApJ Letters, 530, L65) gives a physical basis for why low state black holes appear as LINERS. By linking the Lightman-Eardley instability in an accretion disk to the ori.gin of a wind that contains the broad emission line cloud material this model explains the large widths seen in these lines as being the Keplerian velocity of the disk at the instability radius. For LINERS the key is that below an accretion rate of 10(exp -3)M(sub Edd)the Lightman-Eardley instability falls within the innermost stable orbit of the disk, and so leaves the entire disk stable. No wind occurs, and so no broad emission lines are seen. Most LINERS are likely to be black holes in this low state. Tests of this model are being considered.

  7. Fossil AGN jets as ultrahigh-energy particle accelerators

    NASA Astrophysics Data System (ADS)

    Benford, Gregory; Protheroe, R. J.

    2008-01-01

    Remnants of active galactic nucleus (AGN) jets and their surrounding cocoons leave colossal magnetohydrodynamic (MHD) fossil structures storing total energies ~1060 erg. The original AGN may be dead but the fossil will retain its stable configuration resembling the reversed-field pinch (RFP) encountered in laboratory MHD experiments. In an RFP the longitudinal magnetic field changes direction at a critical distance from the axis, leading to magnetic reconnection there, and to slow decay of the large-scale RFP field. We show that this field decay induces large-scale electric fields which can accelerate cosmic rays with an E-2 power law up to ultrahigh energies with a cut-off depending on the fossil parameters. The cut-off is expected to be rigidity dependent, implying the observed composition would change from light to heavy close to the cut-off if one or two nearby AGN fossils dominate. Given that several per cent of the Universe's volume may house such slowly decaying structures, these fossils may even re-energize ultrahigh-energy cosmic rays from distant/old sources, offsetting the `GZK-losses' due to interactions with photons of the cosmic microwave background radiation and giving evidence of otherwise undetectable fossils. In this case the composition would remain light to the highest energies if distant sources or fossils dominated, but otherwise would be mixed. It is hoped the new generation of cosmic ray experiments such as the Pierre Auger Observatory and ultrahigh-energy neutrino telescopes such as ANITA and lunar Cherenkov experiments will clarify this.

  8. Why are AGN found in high-mass galaxies?

    NASA Astrophysics Data System (ADS)

    Wang, Lan; Kauffmann, Guinevere

    2008-12-01

    There is a strong observed mass dependence of the fraction of nearby galaxies that contain either low-luminosity [low-ionization nuclear emission-line region (LINER) type] or higher luminosity (Seyfert or composite type) active galactic nuclei (AGN). This implies that either only a small fraction of low-mass galaxies contain black holes, or that the black holes in these systems only accrete rarely or at very low rates, and hence are generally not detectable as AGN. In this paper, we use semi-analytic models implemented in the Millennium Simulation to analyse the mass dependence of the merging histories of dark matter haloes and of the galaxies that reside in them. Only a few per cent of galaxies with stellar masses less than M* < 1010Msolar are predicted to have experienced a major merger. The fraction of galaxies that have experienced major mergers increases steeply at larger stellar masses. We argue that if a major merger is required to form the initial seed black hole, the mass dependence of AGN activity in local galaxies can be understood quite naturally. We then investigate when the major mergers that first create these black holes are predicted to occur. High-mass galaxies are predicted to have formed their first black holes at very early epochs. The majority of low-mass galaxies never experience a major merger and hence may not contain a black hole, but a significant fraction of the supermassive black holes that do exist in low-mass galaxies are predicted to have formed recently.

  9. Revisiting Stochastic Variability of AGNs with Structure Functions

    NASA Astrophysics Data System (ADS)

    Kozłowski, Szymon

    2016-08-01

    Discrepancies between reported structure function (SF) slopes and their overall flatness as compared to the expectations from the damped random walk (DRW) model, which generally well describes the variability of active galactic nuclei (AGNs), have triggered us to study this problem in detail. We review common AGN variability observables and identify their most common problems. Equipped with this knowledge, we study ∼9000 r-band AGN light curves from Stripe 82 of the Sloan Digital Sky Survey, using SFs described by stochastic processes with the power exponential covariance matrix of the signal. We model the “subensemble” SFs in the redshift–absolute magnitude bins with the full SF equation (including the turnover and the noise part) and a single power law (SPL; in the “red noise regime” after subtracting the noise term). The distribution of full-equation SF (SPL) slopes peaks at γ =0.55+/- 0.08 (0.52 ± 0.06) and is consistent with the DRW model. There is a hint of a weak correlation of γ with the luminosity and a lack of correlation with the black hole mass. The typical decorrelation timescale in the optical is τ =0.97+/- 0.46 year. The SF amplitude at one year obtained from the SPL fitting is {{SF}}0=0.22+/- 0.06 mag and is overestimated because the SF is already at the turnover part, so the true value is {{SF}}0=0.20+/- 0.06 mag. The asymptotic variability is {{SF}}∞ =0.25+/- 0.06 mag. It is strongly anticorrelated with both the luminosity and the Eddington ratio and is correlated with the black hole mass. The reliability of these results is fortified with Monte Carlo simulations.

  10. Agnes Mary Clerke and the Rise of Astrophysics

    NASA Astrophysics Data System (ADS)

    Brück, M. T.

    2008-03-01

    Acknowledgements; Introduction; 1. Family background in County Cork; 2. Ireland and Italy; 3. London, the literary scene; 4. The History of Astronomy; 5. A circle of astronomers; 6. A visit to South Africa; 7. The System of the Stars; 8. Social life in scientific circles; 9. Homer, the Herschels and a revised History; 10. The opinion moulder; 11. Popularisation, cryogenics and evolution; 12. Problems in Astrophysics; 13. Women in astronomy in Britain in Agnes Clerke's time; 14. Revised System of the Stars; 15. Cosmogonies, cosmology and Nature's spiritual clues; 16. Last days and retrospect; 17. Epilogue; Notes; Appendix; Bibliography; Index.

  11. Hard X-ray AGN Clustering & SMBH Growth

    NASA Astrophysics Data System (ADS)

    Cappelluti, Nico

    2012-09-01

    In this review talk I present the status of the art of the studies on AGN clustering in the X-ray band and its applications in understanding the coeval growth of SMBH and Dark Matter Halos. A well defined picture has been taken up to z~2 while, at high-z, where important physical phenomena connected with SMBH formation, the knowledge is still relegated to the study of anisotropies of the unresolved CXB. I will finally present recent applications of clustering analysis to the study of clustering pattern in the unresolved CXB, and pointing out the possibility of the detection of the first BH in the University through fluctuation analysis.

  12. Dust in the torus of the AGN unified model

    NASA Astrophysics Data System (ADS)

    Mason, Rachel E.

    2015-10-01

    In these proceedings I briefly summarize our current understanding of the dusty torus of the AGN unified model: its structure, composition, and ideas about its origin and evolution. The paper is based on an invited review talk at the 7th Meeting on Cosmic Dust, which covered dust-related topics in areas from comets to debris disks and high-redshift galaxies. This is therefore intended to be an accessible, introductory overview of the torus with some emphasis on the solid-state spectral features observed.

  13. Effects of AGN feedback on ΛCDM galaxies

    NASA Astrophysics Data System (ADS)

    Lagos, Claudia Del P.; Cora, Sofía A.; Padilla, Nelson D.

    2008-08-01

    We study the effects of active galactic nuclei (AGN) feedback on the formation and evolution of galaxies by using a combination of a cosmological N-body simulation of the concordance Lambda cold dark matter (ΛCDM) paradigm and a semi-analytic model of galaxy formation. This model is an improved version of the one described by Cora (2006), which now considers the growth of black holes (BHs) as driven by (i) gas accretion during merger-driven starbursts and mergers with other BHs, (ii) accretion during starbursts triggered by disc instabilities and (iii) accretion of gas cooled from quasi-hydrostatic hot gas haloes. It is assumed that feedback from AGN operates in the last case. The model has been calibrated in order to reproduce observational correlations between BH mass and mass, velocity dispersion and absolute magnitudes of the galaxy bulge. AGN feedback has a strong impact on reducing or even suppressing gas cooling, an effect that becomes important at lower redshifts. This phenomenon helps to reproduce the observed galaxy luminosity function (LF) in the optical and near-infrared bands at z = 0, and the cosmic star formation rate and stellar mass functions over a wide redshift range (0 <~ z <~ 5). It also allows us to have a population of massive galaxies already in place at z >~ 1, which are mostly early-type and have older and redder stellar populations than lower mass galaxies, reproducing the observed bimodality in the galaxy colour distribution, and the morphological fractions. The evolution of the optical QSO LF is also reproduced, provided that the presence of a significant fraction of obscured QSOs is assumed. We explore the effects of AGN feedback during starbursts finding that, in order to obtain a good agreement with observations, these need to be strong enough to expel the reheated gas away from the galaxy halo. We also test new, recent prescriptions for dynamical friction time-scales, and find that they produce an earlier formation of elliptical

  14. The Properties of Low-Luminosity AGN: Variability, Accretion Rate, Black Hole Mass and Color

    NASA Astrophysics Data System (ADS)

    Oleas, Juan; Podjed, Stephanie; Sarajedini, Vicki

    2016-01-01

    We present the results from a study of ~5000 Broad-Line selected AGN from the Sloan Digital Sky Survey DR7. Galaxy and AGN templates have been fit to the SDSS spectra to isolate the AGN component. The sources have absolute magnitudes in the range -23 < Mi < -18 and lie at redshifts less than z ~ 0.8. A variability analysis reveals that the anti-correlation between luminosity and variability amplitude continues to the faintest AGN in our sample (Gallastegui-Aizpun & Sarajedini 2014), though the underlying cause of the relation is still poorly understood. To address this, we further explore the connection between AGN luminosity and variability through measurement of the Hβ line width to determine black hole mass and accretion rate. We find that AGN with the highest variability amplitudes at a given luminosity appear to have lower accretion rates compared to low amplitude variables. We also investigate correlations with AGN color and accretion rate among these low-luminosity AGN.

  15. Photometric and Astrometric Characterization of the La Silla QUEST AGN Variability Survey

    NASA Astrophysics Data System (ADS)

    Coppi, Paolo S.; Cartier, R. A.; QUEST Team

    2014-01-01

    We study the photometric and astrometric properties of the La Silla QUEST AGN Variability Survey and present preliminary results. This wide-field survey is designed to collect well-sampled AGN light curves, on day to year timescales, in order to better characterize the variability properties of a large sample of AGN selected by a variety of other techniques. These properties can then be used to test and improve AGN variability selection techniques, e.g., to better prepare for the arrival of LSST. Additionally, we hope to connect these variability properties to the fundamental physical parameters of AGN such as black hole mass. To achieve this goal, we carry out nightly observations of a set of extragalactic fields with good multiwavelength coverage such as COSMOS. The survey uses the QUEST camera (with ~7.5 square degree field-of-view) operating on the 1m ESO Schmidt located in La Silla, Chile. The survey began in March 2010 and will likely continue for at least two more years. We review our progress and present sample AGN light curves from the first two years of the survey. We use the two-year data to test for possible biases in current selection variability techniques by looking at the known AGN in the COSMOS field. The larger QUEST variabiliity survey, which is now being used to find supernova, will eventually provide high-quality AGN variability data over ~15,000 square degrees of sky.

  16. Alport alloantibodies but not Goodpasture autoantibodies induce murine glomerulonephritis: protection by quinary crosslinks locking cryptic α3(IV) collagen autoepitopes in vivo.

    PubMed

    Luo, Wentian; Wang, Xu-Ping; Kashtan, Clifford E; Borza, Dorin-Bogdan

    2010-09-15

    The noncollagenous (NC1) domains of alpha3alpha4alpha5(IV) collagen in the glomerular basement membrane (GBM) are targets of Goodpasture autoantibodies or Alport posttransplant nephritis alloantibodies mediating rapidly progressive glomerulonephritis. Because the autoepitopes but not the alloepitopes become cryptic upon assembly of alpha3alpha4alpha5NC1 hexamers, we investigated how the accessibility of B cell epitopes in vivo influences the development of glomerulonephritis in mice passively immunized with human anti-GBM Abs. Alport alloantibodies, which bound to native murine alpha3alpha4alpha5NC1 hexamers in vitro, deposited linearly along the mouse GBM in vivo, eliciting crescentic glomerulonephritis in Fcgr2b(-/-) mice susceptible to Ab-mediated inflammation. Goodpasture autoantibodies, which bound to murine alpha3NC1 monomer and dimer subunits but not to native alpha3alpha4alpha5NC1 hexamers in vitro, neither bound to the mouse GBM in vivo nor induced experimental glomerulonephritis. This was due to quinary NC1 crosslinks, recently identified as sulfilimine bonds, which comprehensively locked the cryptic Goodpasture autoepitopes in the mouse GBM. In contrast, non-crosslinked alpha3NC1 subunits were identified as a native target of Goodpasture autoantibodies in the GBM of squirrel monkeys, a species susceptible to Goodpasture autoantibody-mediated nephritis. Thus, crypticity of B cell autoepitopes in tissues uncouples potentially pathogenic autoantibodies from autoimmune disease. Crosslinking of alpha3alpha4alpha5NC1 hexamers represents a novel mechanism averting autoantibody binding and subsequent tissue injury by posttranslational modifications of an autoantigen. PMID:20709951

  17. Alport alloantibodies but not Goodpasture autoantibodies induce murine glomerulonephritis: Protection by quinary crosslinks locking cryptic α3(IV) collagen autoepitopes in vivo 1

    PubMed Central

    Luo, Wentian; Wang, Xu-Ping; Kashtan, Clifford E.; Borza, Dorin-Bogdan

    2010-01-01

    The noncollagenous (NC1) domains of α3α4α5(IV) collagen in the glomerular basement membrane (GBM) are targets of Goodpasture autoantibodies or Alport post-transplant nephritis alloantibodies mediating rapidly progressive glomerulonephritis. Because the autoepitopes but not the alloepitopes become cryptic upon assembly of α3α4α5NC1 hexamers, we investigated how the accessibility of B cell epitopes in vivo influences the development of glomerulonephritis in mice passively immunized with human anti-GBM antibodies. Alport alloantibodies, which bound to native murine α3α4α5NC1 hexamers in vitro, deposited linearly along the mouse GBM in vivo, eliciting crescentic glomerulonephritis in Fcgr2b−/− mice susceptible to antibody-mediated inflammation. Goodpasture autoantibodies, which bound to murine α3NC1 monomer and dimer subunits but not to native α3α4α5NC1 hexamers in vitro, neither bound to the mouse GBM in vivo nor induced experimental glomerulonephritis. This was due to quinary NC1 cross-links, recently identified as sulfilimine bonds, which comprehensively locked the cryptic Goodpasture autoepitopes in the mouse GBM. In contrast, non-crosslinked α3NC1 subunits were identified as a native target of Goodpasture autoantibodies in the GBM of squirrel monkeys—a species susceptible to Goodpasture autoantibody-mediated nephritis. Thus, crypticity of B cell autoepitopes in tissues uncouples potentially pathogenic autoantibodies from autoimmune disease. Crosslinking of α3α4α5NC1 hexamers represents a novel mechanism averting autoantibody binding and subsequent tissue injury by post-translational modifications of an autoantigen. PMID:20709951

  18. The KMOS AGN Survey at High redshift (KASHz): the prevalence and drivers of ionized outflows in the host galaxies of X-ray AGN

    NASA Astrophysics Data System (ADS)

    Harrison, C. M.; Alexander, D. M.; Mullaney, J. R.; Stott, J. P.; Swinbank, A. M.; Arumugam, V.; Bauer, F. E.; Bower, R. G.; Bunker, A. J.; Sharples, R. M.

    2016-02-01

    We present the first results from the KMOS (K-band Multi-Object Spectrograph) AGN (active galactic nuclei) Survey at High redshift (KASHz), a VLT/KMOS integral-field spectroscopic (IFS) survey of z ≳ 0.6 AGN. We present galaxy-integrated spectra of 89 X-ray AGN (L2-10 keV = 1042-1045 erg s-1), for which we observed [O III] (z ≈ 1.1-1.7) or Hα emission (z ≈ 0.6-1.1). The targets have X-ray luminosities representative of the parent AGN population and we explore the emission-line luminosities as a function of X-ray luminosity. For the [O III] targets, ≈50 per cent have ionized gas velocities indicative of gas that is dominated by outflows and/or highly turbulent material (i.e. overall line widths ≳600 km s-1). The most luminous half (i.e. LX > 6 × 1043 erg s-1) have a ≳2 times higher incidence of such velocities. On the basis of our results, we find no evidence that X-ray obscured AGN are more likely to host extreme kinematics than unobscured AGN. Our KASHz sample has a distribution of gas velocities that is consistent with a luminosity-matched sample of z < 0.4 AGN. This implies little evolution in the prevalence of ionized outflows, for a fixed AGN luminosity, despite an order-of-magnitude decrease in average star formation rates over this redshift range. Furthermore, we compare our Hα targets to a redshift-matched sample of star-forming galaxies and despite a similar distribution of Hα luminosities and likely star formation rates, we find extreme ionized gas velocities are up to ≈10 times more prevalent in the AGN-host galaxies. Our results reveal a high prevalence of extreme ionized gas velocities in high-luminosity X-ray AGN and imply that the most powerful ionized outflows in high-redshift galaxies are driven by AGN activity.

  19. DUAL SUPERMASSIVE BLACK HOLE CANDIDATES IN THE AGN AND GALAXY EVOLUTION SURVEY

    SciTech Connect

    Comerford, Julia M.; Schluns, Kyle; Greene, Jenny E.; Cool, Richard J.

    2013-11-01

    Dual supermassive black holes (SMBHs) with kiloparsec-scale separations in merger-remnant galaxies are informative tracers of galaxy evolution, but the avenue for identifying them in large numbers for such studies is not yet clear. One promising approach is to target spectroscopic signatures of systems where both SMBHs are fueled as dual active galactic nuclei (AGNs), or where one SMBH is fueled as an offset AGN. Dual AGNs may produce double-peaked narrow AGN emission lines, while offset AGNs may produce single-peaked narrow AGN emission lines with line-of-sight velocity offsets relative to the host galaxy. We search for such dual and offset systems among 173 Type 2 AGNs at z < 0.37 in the AGN and Galaxy Evolution Survey (AGES), and we find two double-peaked AGNs and five offset AGN candidates. When we compare these results to a similar search of the DEEP2 Galaxy Redshift Survey and match the two samples in color, absolute magnitude, and minimum velocity offset, we find that the fraction of AGNs that are dual SMBH candidates increases from z = 0.25 to z = 0.7 by a factor of ∼6 (from 2/70 to 16/91, or 2.9{sup +3.6}{sub -1.9}% to 18{sup +5}{sub -5}%). This may be associated with the rise in the galaxy merger fraction over the same cosmic time. As further evidence for a link with galaxy mergers, the AGES offset and dual AGN candidates are tentatively ∼3 times more likely than the overall AGN population to reside in a host galaxy that has a companion galaxy (from 16/173 to 2/7, or 9{sup +3}{sub -2}% to 29{sub -19}{sup +26}%). Follow-up observations of the seven offset and dual AGN candidates in AGES will definitively distinguish velocity offsets produced by dual SMBHs from those produced by narrow-line region kinematics, and will help sharpen our observational approach to detecting dual SMBHs.

  20. AGN proximity zone fossils and the delayed recombination of metal lines

    NASA Astrophysics Data System (ADS)

    Oppenheimer, Benjamin D.; Schaye, Joop

    2013-09-01

    We model the time-dependent evolution of metal-enriched intergalactic and circumgalactic gas exposed to the fluctuating radiation field from an active galactic nucleus (AGN). We consider diffuse gas densities (nH = 10-5-10-2.5 cm-3) exposed to the extra-galactic background (EGB) and initially in thermal equilibrium (T ˜ 104-104.5 K). Once the proximate AGN field turns on, additional photo-ionization rapidly ionizes the HI and metals. The enhanced AGN radiation field turns off after a typical AGN lifetime (τAGN = 1-20 Myr) and the field returns to the EGB intensity, but the metals remain out of ionization equilibrium for time scales that can significantly exceed τAGN. We define this phase as the AGN proximity zone `fossil' phase and show that high ionization stages (e.g. OVI, NeVIII, MgX) are in general enhanced, while the abundances of low ions (e.g. CIV, OIV, MgII) are reduced. In contrast, HI re-equilibrates rapidly (≪τAGN) owing to its low neutral fraction at diffuse densities. We demonstrate that metal column densities of intervening gas observed in absorption in quasar sight lines are significantly affected by delayed recombination for a wide range of densities, metallicities, AGN strengths, AGN lifetimes and AGN duty cycles. As an example, we show that a fossil zone model can simultaneously reproduce the observed NeVIII, MgII, HI and other metal columns of the z = 0.927 PG1206+259 absorption system observed by Tripp et al. using a single, T ˜ 104 K phase model. At low redshift even moderate-strength AGN that are off for 90 per cent of the time could significantly enhance the high-ion metal columns in the circum-galactic media of galaxies observed without active AGN. Fossil proximity zones may be particularly important during the quasar era, z ˜ 2-5. Indeed, we demonstrate that at these redshifts a large fraction of the metal-enriched intergalactic medium may consist of out-of-equilibrium fossil zones. AGN proximity zone fossils allow a whole new class

  1. Optically Elusive AGN in the 3XMM Catalog and the Chandra-COSMOS field

    NASA Astrophysics Data System (ADS)

    Pons, Estelle; Watson, Mike; Elvis, Martin; Civano, Francesca M.

    2015-01-01

    'Optically elusive AGN' are powerful X-ray sources (LHX > 1042 erg/s), but are not detected as AGN in the optical. Pons and Watson (2014) showed that in XMM these AGNs are a mix of Narrow Line Seyfert 1s, True Seyfert 2's and weak Seyfert 2s. The nature of these objects, coming from the cross-match of 3XMM with the SDSS-DR9 spectroscopic catalog, has been investigated through a detailed analysis of their IR/optical and X-ray properties. The fainter Chandra-COSMOS field should be rich in optically elusive AGNs as ¾ of the AGNs there are narrow-lined. There are ~850 Chandra-COSMOS galaxy spectra, mainly from five different telescopes (SDSS, Magellan, MMT, VLT and Keck). To find optically elusive objects, we investigate the optical classification using emission line diagnostic diagrams. For low redshift galaxies (z~<0.7) the standard BPT diagram ([OIII

  2. Skimmin, a Coumarin from Hydrangea paniculata, Slows down the Progression of Membranous Glomerulonephritis by Anti-Inflammatory Effects and Inhibiting Immune Complex Deposition

    PubMed Central

    Xin, Hongqi; Li, Yan; Zhang, Dongming; Shi, Jing; Yang, Jingzhi

    2013-01-01

    Skimmin is one of the major pharmacologically active molecules present in Hydrangea paniculata, a medical herb used in the traditional Chinese medicine as an anti-inflammatory agent. In the current study, we attempted to investigate its renoprotective activity and underlying mechanisms in a rat model of membranous glomerulonephritis induced by cationic bovine serum albumin (c-BSA). Sprague-Dawley (SD) rats were divided into five groups, including normal control, model control, Mycophenolate Mofetil-treated group, and two skimming-treated groups (15 mg/kg and 30 mg/kg). Our research showed that treatment with skimmin significantly reduced the levels of blood urea nitrogen (BUN), urinary albumin excretion (UAE), and serum creatinine (Scr) as compared with model control after experimental induction of membranous glomerulonephritis (P < 0.01). Moreover, glomerular hypercellularity, tubulointerstitial injury, and glomerular deposition of IgG were less intense after skimmin treatment. By immunochemistry analysis, we demonstrated that skimmin could significantly inhibit interleukin-1β (IL1β) and IL-6 expression (P < 0.05), reduce the loss of nephrin and podocin, and suppress the infiltration of renal interstitium by CD3-positive T cell and CD20-positive B cell. These results suggest that treatment with skimmin can significantly improve renal function and suppress the IgG deposition as well as the development of glomerular lesions in a rat model of membranous glomerulonephritis. PMID:23990847

  3. PRIMUS: The Dependence of AGN Accretion on Host Stellar Mass and Color

    NASA Astrophysics Data System (ADS)

    Aird, James; Coil, Alison L.; Moustakas, John; Blanton, Michael R.; Burles, Scott M.; Cool, Richard J.; Eisenstein, Daniel J.; Smith, M. Stephen M.; Wong, Kenneth C.; Zhu, Guangtun

    2012-02-01

    We present evidence that the incidence of active galactic nuclei (AGNs) and the distribution of their accretion rates do not depend on the stellar masses of their host galaxies, contrary to previous studies. We use hard (2-10 keV) X-ray data from three extragalactic fields (XMM-LSS, COSMOS, and ELAIS-S1) with redshifts from the Prism Multi-object Survey to identify 242 AGNs with L 2-10 keV = 1042-44 erg s-1 within a parent sample of ~25,000 galaxies at 0.2 < z < 1.0 over ~3.4 deg2 and to i ~ 23. We find that although the fraction of galaxies hosting an AGN at fixed X-ray luminosity rises strongly with stellar mass, the distribution of X-ray luminosities is independent of mass. Furthermore, we show that the probability that a galaxy will host an AGN can be defined by a universal Eddington ratio distribution that is independent of the host galaxy stellar mass and has a power-law shape with slope -0.65. These results demonstrate that AGNs are prevalent at all stellar masses in the range 9.5 and that the same physical processes regulate AGN activity in all galaxies in this stellar mass range. While a higher AGN fraction may be observed in massive galaxies, this is a selection effect related to the underlying Eddington ratio distribution. We also find that the AGN fraction drops rapidly between z ~ 1 and the present day and is moderately enhanced (factor ~2) in galaxies with blue or green optical colors. Consequently, while AGN activity and star formation appear to be globally correlated, we do not find evidence that the presence of an AGN is related to the quenching of star formation or the color transformation of galaxies.

  4. Stellar and quasar feedback in concert: effects on AGN accretion, obscuration, and outflows

    NASA Astrophysics Data System (ADS)

    Hopkins, Philip F.; Torrey, Paul; Faucher-Giguère, Claude-André; Quataert, Eliot; Murray, Norman

    2016-05-01

    We study the interaction of feedback from active galactic nuclei (AGN) and a multiphase interstellar medium (ISM), in simulations including explicit stellar feedback, multiphase cooling, accretion-disc winds, and Compton heating. We examine radii ˜0.1-100 pc around a black hole (BH), where the accretion rate on to the BH is determined and where AGN-powered winds and radiation couple to the ISM. We conclude: (1) the BH accretion rate is determined by exchange of angular momentum between gas and stars in gravitational instabilities. This produces accretion rates ˜0.03-1 M⊙ yr-1, sufficient to power luminous AGN. (2) The gas disc in the galactic nucleus undergoes an initial burst of star formation followed by several million years where stellar feedback suppresses the star formation rate (SFR). (3) AGN winds injected at small radii with momentum fluxes ˜LAGN/c couple efficiently to the ISM and have dramatic effects on ISM properties within ˜100 pc. AGN winds suppress the nuclear SFR by factors ˜10-30 and BH accretion rate by factors ˜3-30. They increase the outflow rate from the nucleus by factors ˜10, consistent with observational evidence for galaxy-scale AGN-driven outflows. (4) With AGN feedback, the predicted column density distribution to the BH is consistent with observations. Absent AGN feedback, the BH is isotropically obscured and there are not enough optically thin sightlines to explain type-I AGN. A `torus-like' geometry arises self-consistently as AGN feedback evacuates gas in polar regions.

  5. Acute nephritic syndrome

    MedlinePlus

    ... and adolescents include: Hemolytic uremic syndrome Henoch-Schönlein purpura IgA nephropathy Post-streptococcal glomerulonephritis Common causes in ... Heart failure - overview Hemolytic-uremic syndrome Henoch-Schönlein purpura Hepatitis High blood pressure Hypersensitivity vasculitis IgA nephropathy ...

  6. Simulations of the OzDES AGN reverberation mapping project

    NASA Astrophysics Data System (ADS)

    King, Anthea L.; Martini, Paul; Davis, Tamara M.; Denney, K. D.; Kochanek, C. S.; Peterson, Bradley M.; Skielboe, Andreas; Vestergaard, Marianne; Huff, Eric; Watson, Darach; Banerji, Manda; McMahon, Richard; Sharp, Rob; Lidman, C.

    2015-10-01

    As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ≥500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrain the radius-luminosity (R-L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for ˜35-45 per cent of the quasars. AGN with shorter lags and greater variability are more likely to yield a lag measurement, and objects with lags ≲6 months or ˜1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R-L relationship parameters for H β, Mg II λ2798, and C IV λ1549. Extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R-L parameter constraints for all broad emission lines.

  7. An AGN Identification for 3EG J2006-2321

    NASA Technical Reports Server (NTRS)

    Wallace, P. M.; Halpern, J. P.; Magalhaes, A. M.; Thompson, D. J.; White, Nicholas E. (Technical Monitor)

    2001-01-01

    We present a multiwavelength analysis of the high-energy gamma-ray source 3EG J2006-2321 (l = 18 deg.82, b = -26 deg.26). The flux of this source above 100 MeV is shown to be variable on time scales of days and months. Optical observations and careful examination of archived radio data indicate that its most probable identification is with PMN J2005-2310, a flat-spectrum radio quasar with a 5GHz flux density of 260 mJy. Study of the V = 19.3 optical counterpart indicates a redshift of 0.833 and variable linear polarization. No X-ray source has been detected near the position of PMN J2005-2310, but an X-ray upper limit is derived from ROSAT data. This upper limit provides for a spectral energy distribution with global characteristics similar to those of known gamma-ray blazars. Taken together, these data indicate that 3EG J2006-2321, listed as unidentified in the 3rd EGRET Catalog, is a member of the blazar class of AGN. The 5-GHz radio flux density of this blazar is the lowest of the 68 EGRET-detected AGN. The fact that EGRET has detected such a source has implications for unidentified EGRET sources, particularly those at high latitudes (absolute value of b greater than 30 deg), many of which may be blazars.

  8. Hot Gas and AGN Feedback in Galaxies and Nearby Groups

    NASA Astrophysics Data System (ADS)

    Jones, Christine; Forman, William; Bogdan, Akos; Randall, Scott; Kraft, Ralph; Churazov, Eugene

    2013-07-01

    Massive galaxies harbor a supermassive black hole at their centers. At high redshifts, these galaxies experienced a very active quasar phase, when, as their black holes grew by accretion, they produced enormous amounts of energy. At the present epoch, these black holes still undergo occasional outbursts, although the mode of their energy release is primarily mechanical rather than radiative. The energy from these outbursts can reheat the cooling gas in the galaxy cores and maintain the red and dead nature of the early-type galaxies. These outbursts also can have dramatic effects on the galaxy-scale hot coronae found in the more massive galaxies. We describe research in three areas related to the hot gas around galaxies and their supermassive black holes. First we present examples of galaxies with AGN outbursts that have been studied in detail. Second, we show that X-ray emitting low-luminosity AGN are present in 80% of the galaxies studied. Third, we discuss the first examples of extensive hot gas and dark matter halos in optically faint galaxies.

  9. XMM-Newton, powerful AGN winds and galaxy feedback

    NASA Astrophysics Data System (ADS)

    Pounds, K.; King, A.

    2016-06-01

    The discovery that ultra-fast ionized winds - sufficiently powerful to disrupt growth of the host galaxy - are a common feature of luminous AGN is major scientific breakthrough led by XMM-Newton. An extended observation in 2014 of the prototype UFO, PG1211+143, has revealed an unusually complex outflow, with distinct and persisting velocities detected in both hard and soft X-ray spectra. While the general properties of UFOs are consistent with being launched - at the local escape velocity - from the inner disc where the accretion rate is modestly super-Eddington (King and Pounds, Ann Rev Astron Astro- phys 2015), these more complex flows have raised questions about the outflow geometry and the importance of shocks and enhanced cooling. XMM-Newton seems likely to remain the best Observatory to study UFOs prior to Athena, and further extended observations, of PG1211+143 and other bright AGN, have the exciting potential to establish the typical wind dynamics, while providing new insights on the accretion geometry and continuum source structure. An emphasis on such large, coordinated observing programmes with XMM-Newton over the next decade will continue the successful philosophy pioneered by EXOSAT, while helping to inform the optimum planning for Athena

  10. The evolution of AGN's at x ray wavelengths

    NASA Technical Reports Server (NTRS)

    Maccacaro, Tommaso; Dellaceca, R.; Gioia, I. M.; Stocke, J. T.; Wolter, A.

    1992-01-01

    The cosmological evolution and the Luminosity Function (LF) of x-ray selected Active Galactic Nuclei (AGN) are discussed. The sample used is extracted from the Einstein Observatory Extended Medium Sensitivity Survey (EMSS) and consists of more than 420 objects. Preliminary results from the Rosat all sky survey data confirm the correctness of the optical identification of the EMSS sources, thus giving confidence to the results obtained from the analysis of the AGN sample. The XLF observed at different redshifts gives direct evidence of cosmological evolution. Data were analyzed within the framework of luminosity evolution models and the two most common evolutionary forms were considered. Luminosity dependent evolution is required if the evolution function has the exponential form, whereas the simpler pure luminosity evolution model is still acceptable if the evolution function has the power law form. Using the whole sample of objects the number counts and the devolved XLF were derived. A comparison of the EMSS Data with preliminary Rosat results indicates an overall agreement.

  11. Exploring the Variability Characteristics of the Fermi AGN Sample

    NASA Astrophysics Data System (ADS)

    Shrader, Chris R.

    2016-04-01

    The Fermi Gamma-Ray Space Telescope (Fermi) has cataloged over 3000 gamma-ray (>100 MeV) point sources of which ~70% are likely AGN. The AGN are predominantly representative of the radio-loud “blazar” subclass. The emission from these objects is known to be dominated by relativistic beaming and is almost always variable, often exhibiting high-amplitude flaring. To date there have been numerous studies of individual objects including multi-wavelength campaigns with some including parsec-scale radio jet morphological studies. These studies have led to new insight in to our understanding of the blazar phenomena and jet propagation. However, there remains a dearth of statistical information on the variability characteristics of the population in aggregate. What, for example, are the distributions of flare amplitudes, durations, temporal profiles and recurrence histories among the gamma-ray blazar subclasses? We present some results of our study of a large ( ~103) set of gamma-ray light curves. For the brightest subset we explore in greater detail their properties such as morphologies and their rise and decay timescales. We include where plausible the associated energy dependencies of these rise and decay profiles. We discuss our results in terms of the possible implications on the scale and location of jet structures associated with the emission sites and the cooling timescales of the electron population producing the gamma rays.

  12. Simulations of the OzDES AGN reverberation mapping project

    SciTech Connect

    King, Anthea L.; Martini, Paul; Davis, Tamara M.; Denney, K. D.; Kochanek, C. S.; Peterson, Bradley M.; Skielboe, Andreas; Vestergaard, Marianne; Huff, Eric; Watson, Darach; Banerji, Manda; McMahon, Richard; Sharp, Rob; Lidman, C.

    2015-08-26

    As part of the Australian spectroscopic dark energy survey (OzDES) we are carrying out a large-scale reverberation mapping study of ~500 quasars over five years in the 30 deg2 area of the Dark Energy Survey (DES) supernova fields. These quasars have redshifts ranging up to 4 and have apparent AB magnitudes between 16.8 mag < r < 22.5 mag. The aim of the survey is to measure time lags between fluctuations in the quasar continuum and broad emission-line fluxes of individual objects in order to measure black hole masses for a broad range of active galactic nuclei (AGN) and constrain the radius–luminosity (R–L) relationship. Here we investigate the expected efficiency of the OzDES reverberation mapping campaign and its possible extensions. We expect to recover lags for ~35–45 % of the quasars. AGN with shorter lags and greater variability are more likely to yield a lag measurement, and objects with lags ≲6 months or ~1 yr are expected to be recovered the most accurately. The baseline OzDES reverberation mapping campaign is predicted to produce an unbiased measurement of the R–L relationship parameters for Hβ, MgIIλ2798, and C IVλ1549. As a result, extending the baseline survey by either increasing the spectroscopic cadence, extending the survey season, or improving the emission-line flux measurement accuracy will significantly improve the R–L parameter constraints for all broad emission lines.

  13. 'Harder when Brighter' Spectral Variability in Low-Luminosity AGN

    NASA Astrophysics Data System (ADS)

    Connolly, S.; McHardy, I.; Skipper, C.; Dwelly, T.

    2015-07-01

    We present X-ray spectral variability of four low accretion rate AGN - M81, NGC 1097, NGC 1052 and NGC 3998 - as observed by Swift and RXTE. All four objects were selected due to having spectra which hardened with increasing count rate, converse to the `softer when brighter' behaviour normally observed in AGN with higher accretion rates. The spectra were summed in flux bins and fitted with a variety of models. A simple absorbed power law model was found to fit the spectra of M81, NGC 1097 and NGC 3998 well, whilst NGC 1052 required a partially covered power law model. In all four cases, the most likely main source of spectral variability is found to be luminosity-dependent changes in the photon index of the power law component. An anticorrelation between the photon index and the count rate is found in all of the sources. The anticorrelation is likely to be caused by accretion via a radiatively-inefficient accretion flow, expected in low-Eddington ratio systems such as these, and/or due to the presence of a jet. This behaviour is similar to that seen in the `hard state' of X-ray binaries, implying that these LLAGN are in a similar state.

  14. Dramatic long-term X-ray variability in AGNs

    NASA Astrophysics Data System (ADS)

    Moran, Edward C.

    2016-04-01

    Dramatic X-ray and optical variability on ˜ 10 year timescales has been discovered recently in a handful of quasars, which may provide important new insight into the issue of how luminous AGNs are fueled. We have assembled a new sample of extremely variable X-ray sources from archival Einstein and ROSAT data that could increase substantially the number of such objects known. The sources in our sample varied in X-ray flux by at least a factor of 7-8 over a 10-year span, and most exhibited significantly larger variability amplitudes (10 to over 100). We present the details of how our sample was assembled and preliminary results regarding the identifications, properties, and X-ray histories of the objects. Although a heterogeneous population is expected, some sources in the sample are associated with broad-line AGNs, including a radio-quiet quasar at z = 1.3 that decreased in X-ray luminosity by a factor of 40.

  15. Effects of AGN feedback in galaxy groups and Intergalactic Medium

    NASA Astrophysics Data System (ADS)

    Lagos, C.; Padilla, N.; Cora, S.

    2009-05-01

    The combination of Cosmological numerical simulations and semi-analytical models of galaxy formation is a very appropriate method to study how different phenomena influence the galaxy and galaxy cluster formation. The main advantage of this combination consists in the fact that N-body simulations do not need to be rerun every time a change in the assumptions about baryonic processes is made since these are included in the semi-analytical models which run on the final N-Body simulation output. The Semi-analytic model takes into account radiative cooling of gas, stellar formation and different types of SN contribution, which eject energy and metals to the interstellar medium, allowing the chemical enrichment of the intergalactic medium. In this project we use the semi-analytic hybrid model by Cora (2006, MNRAS, 368, 1540) and implement the AGN feedback, in two modes, the QSO mode (which takes into account mergers and galactic disk instabilities), and the Radio mode, which modifies the cooling in the galaxies These two processes allow to suppress the super flows in the hybrid model, and allows the study of QSOs in galaxy groups. This new implementation opens different possibles studies including the QSO luminosity function, the anti-hierarchical evolution of Mass Function, the BH mass and bulge mass relation, Color-Magnitude diagrams, TF relation, the galaxy luminosity function, the effects of AGN in neighbor galaxies and the behavior of QSOs in the sub-millimeter window.

  16. Eclipsing the innermost accretion disc regions in AGN

    NASA Astrophysics Data System (ADS)

    Sanfrutos, M.; Miniutti, G.; Dovčiak, M.; Agís-González, B.

    2016-05-01

    Variable X-ray absorption has been observed in active galactic nuclei (AGN) on several time scales. Observations allow us to identify the absorber with clouds associated either with the clumpy torus (parsec scales, long timescales) or with the broad line region (BLR) (short timescales). In the latter, the cloud size has been estimated to be of the order of few gravitational radii from the observed absorption variability. Such small cloud sizes are comparable to the X-ray emitting regions so that a detailed modeling of occultation events in AGN has the potential of enabling us to infer accurately the geometry of the system. We have developed a relativistic X-ray spectral model for occultation events and we present here theoretical predictions on the different observables that can be inferred by studying X-ray eclipses in simulated XMM-Newton data. These include the size of the X-ray emitting regions as well as more fundamental parameters such as the black hole spin and the system inclination. We find that absorption varies as a function of the energy range and that its maximum takes place when the approaching part of the accretion disc is covered. Therefore we study the hard-to-soft (H / S) ratio light curves produced during an eclipse and use them to characterise the properties of the inner accretion disc in a new model-independent way.

  17. Using gravitationally lensed images to investigate the intrinsic AGN variability

    NASA Astrophysics Data System (ADS)

    Martí-Vidal, I.; Muller, S.

    2016-05-01

    We discuss about how the relative flux densities among the images of gravitationally-lensed active galactic nuclei (AGN), can be used to study the intrinsic AGN variability with high accuracy. Multi-frequency monitoring observations of resolved gravitational lenses can allow us to detect signals of very weak variability and also provide information about the jet opacity and structure. As an example, we investigate the variability of the flux-density ratio between the two lensed images of the blazar B 0218+357, using dual-frequency cm-wave observations. Similar to our previously reported submm-wave observations of the lensed blazar PKS 1830-211, we observe a clear chromatic variability, starting short before an increase in the flux-density of the blazar. The evolution of the flux-density ratios between the blazar images shows a more clear and rich structure than that of the mere lightcurves of each individual image. The accuracy in the ratio measurements is allowing us to see variability episodes in the blazar that are weaker than the natural scatter in the absolute flux-density measurements. A simple opacity model in the jet is used to consistently explain the difference between the flux-density-ratio evolution at the two frequencies.

  18. Studying AGN Feedback in Galaxy Clusters and Groups with Athena

    NASA Astrophysics Data System (ADS)

    Sanders, Jeremy; Athena Topical PanelAGN Feedback in Clusters; Groups

    2015-09-01

    In the centres of clusters of galaxies and groups the central active galactic nuclei are playing a vital role in preventing the rapid cooling of the surrounding hot atmosphere. Important scientific questions remain unanswered, however. These include (1) What is the mechanism by which the energy from jets is dissipated and distributed through intracluster or intragroup medium? (2) How is the AGN fuelling regulated? (3) What is the cumulative impact of powerful radio galaxies on baryons over cosmic time? With its high spectral resolution, good spatial resolution and large effective area, Athena promises to make important progress in answering these questions. For the first time it will measure both the spatially-resolved velocity distribution and thermodynamics of the cluster core region, allowing us to measure all the energetic contributions to feedback and cooling in the hot plasma. We describe how Athena will address these areas, as described in our supporting paper for the Athena mission proposal on AGN feedback in galaxy clusters and groups.

  19. AGN-Induced Cavities in NGC 1399 And NGC 4649

    SciTech Connect

    Shurkin, K.; Dunn, R.J.H.; Gentile, G.; Taylor, G.B.; Allen, S.W.; /KIPAC, Menlo Park

    2007-11-14

    We present an analysis of archival Chandra and VLA observations of the E0 galaxy NGC1399 and the E2 galaxy NGC4649 in which we investigate cavities in the surrounding X-ray emitting medium caused by the central AGN. We calculate the jet power required for the AGN to evacuate these cavities and find values of {approx} 8x10{sup 41} erg s-1 and {approx} 14x10{sup 41} erg s{sup -1} for the lobes of NGC1399 and {approx} 7x10{sup 41} erg s{sup -1} and {approx} 6x1041 erg s{sup -1} for those of NGC4649. We also calculate the k/f values for each cavity, where k is the ratio of the total particle energy to that of electrons radiating in the range of 10 MHz to 10 GHz, and f is the volume filling factor of the plasma in the cavity. We find that the values of k/f for the lobes of NGC1399 are {approx} 93 and {approx} 190, and those of the lobes of NGC4649 are {approx} 15000 and {approx} 12000. We conclude that the assumed spectrum describes the electron distribution in the lobes of NGC1399 reasonably well, and that there are few entrained particles. For NGC4649, either there are many entrained particles or the model spectrum does not accurately describe the population of electrons.

  20. Dynamics of matter available for accretion in AGN

    NASA Astrophysics Data System (ADS)

    Proga, Daniel

    We propose to study fluid dynamics in the central regions of active galaxies. Several key attributes of AGN, such as infall rates onto the central black hole and the geometry and rates of outward energy and momentum transfer, are determined in their central regions. However, despite many years of intensive studies, how radiation and mass outflows affect the structure of active galaxies remains uncertain, mostly because multi- dimensional geometrical effects and the dynamics of gas and dust are poorly understood. We will construct time-dependent, multi-dimensional radiation hydrodynamical simulations to study, from first principles, the morphology of central galactic flows on scales ranging from subparsec to tens of parsecs. The novel features of our proposed models are: (1) radiative heating and cooling of dust and gas, (2) radiation pressure on dust and gas,
(3) the essential physics of dust sublimation, and (4) radiative transfer. The results of this project will reveal the basic physical properties of flows in AGN with unprecedented accuracy and detail. We will use our models to calculate diagnostics such as line profiles, broad band spectra, and intensity maps. These diagnostics will be compared with observations by both current NASA missions such as HST, Chandra, Spitzer, and Swift and planned missions such as JWST.

  1. The AGN-driven shock in NGC 4472

    NASA Astrophysics Data System (ADS)

    Gendron-Marsolais, Marie-Lou; Kraft, Ralph P.; Bogdan, Akos; Forman, William R.; Hlavacek-Larrondo, Julie; Jones, Christine; Nulsen, Paul; Randall, Scott W.; Roediger, Elke

    2016-04-01

    Chandra observations of most cool core clusters of galaxies have revealed large cavities where the inflation of the jet-driven radio bubbles displace the cluster gas. In a few cases, outburst shocks, likely driven by cavity inflation, are detected in the ambient gas. AGN-driven shocks may be key to balancing the radiative losses as shocks will increase the entropy of, and thereby heat, the diffuse gas. We will present initial results on deep Chandra observations of the nearby (D=17 Mpc) early-type massive elliptical galaxy NGC 4472, the most optically luminous galaxy in the local Universe, lying on the outskirts of the Virgo cluster. The X-ray observations show clear cavities in the X-ray emission at the position of the radio lobes, and rings of enhanced X-ray emission just beyond the lobes. We will present results from our analysis to determine whether the lobes are inflating supersonically or are rising buoyantly. We will compare the energy and power of this AGN outburst with previous powerful radio outbursts in clusters and groups to determine whether this outburst lies on the same scaling relations or whether it represents a new category of outburst.

  2. Therapeutic effects and mechanism of conditioned media from human mesenchymal stem cells on anti-GBM glomerulonephritis in WKY rats.

    PubMed

    Iseri, Ken; Iyoda, Masayuki; Ohtaki, Hirokazu; Matsumoto, Kei; Wada, Yukihiro; Suzuki, Taihei; Yamamoto, Yasutaka; Saito, Tomohiro; Hihara, Kei; Tachibana, Shohei; Honda, Kazuho; Shibata, Takanori

    2016-06-01

    Recent studies have demonstrated that conditioned media derived from mesenchymal stem cells (MSC-CM) have therapeutic effects in various experimental diseases. However, the therapeutic mechanism is not fully understood. In the present study, we investigated the therapeutic effects and mechanism of MSC-CM in experimental antiglomerular basement membrane glomerulonephritis. We administered either MSC-CM or vehicle from day 0 to day 10 after the induction of nephrotoxic serum nephritis in Wistar-Kyoto rats. In vitro, we analyzed the effects of MSC-CM on TNF-α-mediated cytokine production in cultured normal human mesangial cells, proximal tubular (HK-2) cells, human umbilical vein endothelial cells, and monocytes (THP-1 and peripheral blood mononuclear cells). Compared with vehicle treatment, MSC-CM treatment improved proteinuria and renal dysfunction. Histologically, MSC-CM-treated rats had reduced crescent formation and glomerular ED1(+) macrophage infiltration and increased glomerular ED2(+) macrophage infiltration. Increased serum monocyte chemoattractant protein (MCP)-1 levels were observed in MSC-CM-treated rats. Renal cortical mRNA expression levels of proinflammatory cytokines, such as TNF-α and IL-6, and of the T helper cell 1 cytokine interferon-γ were greatly decreased by MSC-CM treatment. In vitro, pretreatment with MSC-CM blocked TNF-α-mediated IL-8 release in normal human mesangial cells and HK-2 cells. TNF-α-mediated MCP-1 release was enhanced by pretreatment with MSC-CM in human umbilical vein endothelial cells and HK-2 cells and was strikingly enhanced in THP-1 cells. Stimulation of peripheral blood mononuclear cells with a combination of MCP-1 and IL-4 enhanced the expression of M2-associated genes compared with IL-4 alone. We demonstrated that MSC-CM had therapeutic effects in experimental antiglomerular basement membrane glomerulonephritis that were mediated through anti-inflammatory effects that were partly due to acceleration of M2 macrophage

  3. PRIMUS: INFRARED AND X-RAY AGN SELECTION TECHNIQUES AT 0.2 < z < 1.2

    SciTech Connect

    Mendez, Alexander J.; Coil, Alison L.; Aird, James; Diamond-Stanic, Aleksandar M.; Moustakas, John; Blanton, Michael R.; Cool, Richard J.; Eisenstein, Daniel J.; Wong, Kenneth C.; Zhu Guangtun

    2013-06-10

    We present a study of Spitzer/IRAC and X-ray active galactic nucleus (AGN) selection techniques in order to quantify the overlap, uniqueness, contamination, and completeness of each. We investigate how the overlap and possible contamination of the samples depend on the depth of both the IR and X-ray data. We use Spitzer/IRAC imaging, Chandra and XMM-Newton X-ray imaging, and spectroscopic redshifts from the PRism MUlti-object Survey to construct galaxy and AGN samples at 0.2 < z < 1.2 over 8 deg{sup 2}. We construct samples over a wide range of IRAC flux limits (SWIRE to GOODS depth) and X-ray flux limits (10 ks to 2 Ms). We compare IR-AGN samples defined using both the IRAC color selection of Stern et al. and Donley et al. with X-ray-detected AGN samples. For roughly similar depth IR and X-ray surveys, we find that {approx}75% of IR-selected AGNs are also identified as X-ray AGNs. This fraction increases to {approx}90% when comparing against the deepest X-ray data, indicating that at most {approx}10% of IR-selected AGNs may be heavily obscured. The IR-AGN selection proposed by Stern et al. suffers from contamination by star-forming galaxies at various redshifts when using deeper IR data, though the selection technique works well for shallow IR data. While similar overall, the IR-AGN samples preferentially contain more luminous AGNs, while the X-ray AGN samples identify a wider range of AGN accretion rates including low specific accretion rate AGNs, where the host galaxy light dominates at IR wavelengths. The host galaxy populations of the IR and X-ray AGN samples have similar rest-frame colors and stellar masses; both selections identify AGNs in blue, star-forming and red, quiescent galaxies.

  4. PRIMUS: Infrared and X-Ray AGN Selection Techniques at 0.2 < z < 1.2

    NASA Astrophysics Data System (ADS)

    Mendez, Alexander J.; Coil, Alison L.; Aird, James; Diamond-Stanic, Aleksandar M.; Moustakas, John; Blanton, Michael R.; Cool, Richard J.; Eisenstein, Daniel J.; Wong, Kenneth C.; Zhu, Guangtun

    2013-06-01

    We present a study of Spitzer/IRAC and X-ray active galactic nucleus (AGN) selection techniques in order to quantify the overlap, uniqueness, contamination, and completeness of each. We investigate how the overlap and possible contamination of the samples depend on the depth of both the IR and X-ray data. We use Spitzer/IRAC imaging, Chandra and XMM-Newton X-ray imaging, and spectroscopic redshifts from the PRism MUlti-object Survey to construct galaxy and AGN samples at 0.2 < z < 1.2 over 8 deg2. We construct samples over a wide range of IRAC flux limits (SWIRE to GOODS depth) and X-ray flux limits (10 ks to 2 Ms). We compare IR-AGN samples defined using both the IRAC color selection of Stern et al. and Donley et al. with X-ray-detected AGN samples. For roughly similar depth IR and X-ray surveys, we find that ~75% of IR-selected AGNs are also identified as X-ray AGNs. This fraction increases to ~90% when comparing against the deepest X-ray data, indicating that at most ~10% of IR-selected AGNs may be heavily obscured. The IR-AGN selection proposed by Stern et al. suffers from contamination by star-forming galaxies at various redshifts when using deeper IR data, though the selection technique works well for shallow IR data. While similar overall, the IR-AGN samples preferentially contain more luminous AGNs, while the X-ray AGN samples identify a wider range of AGN accretion rates including low specific accretion rate AGNs, where the host galaxy light dominates at IR wavelengths. The host galaxy populations of the IR and X-ray AGN samples have similar rest-frame colors and stellar masses; both selections identify AGNs in blue, star-forming and red, quiescent galaxies.

  5. [Drug-induced acute kidney injury].

    PubMed

    Derungs, Adrian

    2015-12-01

    Due to their physiological function, the kidneys are exposed to high concentrations of numerous drugs and their metabolites, making them vulnerable to drug-related injuries. This article provides an overview of the pathophysiological mechanisms involved in nephrotoxicity, the most common nephrotoxic drugs, and the risk factors for the occurrence of drug-induced acute kidney injuries. NSAIDs, diuretics, ACE inhibitors, and angiotensin II receptor blockers (ARBs} are the most frequent prerenal causes of an acute elevation in creatinine levels. Primary vascular damage arises from thrombotic microangiopathy (e. g. due to cic/osporin, tacrolimus, muromonab-CD3, mitomycin C, quinine, ticlopidine, clopidogrel}. Anticoagulants and thrombolytic medications lead to secondary blood vessel damage by cholesterol emboli, embolism of thrombus material into the periphery or bleeding. Tubulopathies can be observed on treatment with ifosfamide and cisplatin (rarely with cyclophosphamide or carboplatin), aminoglycosides, vancomycin, and radiocontrast agents. Immunological mechanisms underlie interstitial nephritides, which are induced by drugs in about 85% of cases. In drug-induced glomerulopathies;- renal biopsy allows closer identification of the triggering medication. Drug-induced systemic lupus erythematosus (SLE} represents a special form of immune complex glomerulonephritis and can be triggered by procainamide, hydralazine, isoniazid, methyldopa, quinidine, chlorpromazine, and propylthiouracil. Crystal-induced kidney injury is caused by precipitation of drugs (e. g. aciclovir, sulfonamide antibiotics, methotrexate, indinavir) in the renal tubules and the urine-conducting organs with consecutive obstruction thereof. PMID:26654816

  6. Acute Bronchitis

    MedlinePlus

    Bronchitis is an inflammation of the bronchial tubes, the airways that carry air to your lungs. It ... chest tightness. There are two main types of bronchitis: acute and chronic. Most cases of acute bronchitis ...

  7. PRIMUS + DEEP2: Clustering of X-Ray, Radio, and IR-AGNs at z~0.7

    NASA Astrophysics Data System (ADS)

    Mendez, Alexander J.; Coil, Alison L.; Aird, James; Skibba, Ramin A.; Diamond-Stanic, Aleksandar M.; Moustakas, John; Blanton, Michael R.; Cool, Richard J.; Eisenstein, Daniel J.; Wong, Kenneth C.; Zhu, Guangtun

    2016-04-01

    We measure the clustering of X-ray, radio, and mid-IR-selected active galactic nuclei (AGNs) at 0.2\\lt z\\lt 1.2 using multi-wavelength imaging and spectroscopic redshifts from the PRIMUS and DEEP2 redshift surveys, covering seven separate fields spanning ∼10 deg 2 . Using the cross-correlation of AGNs with dense galaxy samples, we measure the clustering scale length and slope, as well as the bias, of AGNs selected at different wavelengths. Similar to previous studies, we find that X-ray and radio AGNs are more clustered than mid-IR-selected AGNs. We further compare the clustering of each AGN sample with matched galaxy samples designed to have the same stellar mass, star-formation rate (SFR), and redshift distributions as the AGN host galaxies and find no significant differences between their clustering properties. The observed differences in the clustering of AGNs selected at different wavelengths can therefore be explained by the clustering differences of their host populations, which have different distributions in both stellar mass and SFR. Selection biases inherent in AGN selection therefore determine the clustering of observed AGN samples. We further find no significant difference between the clustering of obscured and unobscured AGNs, using IRAC or Wide-field Infrared Survey Explorer colors or X-ray hardness ratio.

  8. The combination of tacrolimus and entecavir improves the remission of HBV-associated glomerulonephritis without enhancing viral replication

    PubMed Central

    Wang, Lifen; Ye, Zhiming; Liang, Huaban; Zhang, Bin; Xu, Lixia; Feng, Zhonglin; Liu, Shuangxin; Shi, Wei

    2016-01-01

    Background: Tacrolimus inhibits hepatitis B virus entry into hepatocytes through targeting the HBV receptor, sodium taurocholate cotransporting polypeptide. This study was performed to evaluate the efficacy and safety of Tacrolimus combined with entecavir antiviral therapy for HBV-associated glomerulonephritis patients with biopsy-proven membranous nephropathy. Method: A cohort of 42 patients was enrolled in this retrospective study. Twenty-three patients received Tacrolimus (0.05 mg/kg/day) in combination entecavir over 24 weeks, whereas the other 19 patients only received entecavir monotherapy. Results: The probability of proteinuria remission in the Tacrolimus+entecavir group was 69 and 87% after 12 and 24 weeks, whereas was only 26 and 42%, respectively, in the entecavir group. The mean time to partial or complete remission was 18.6 weeks in the Tacrolimus+entecavir group and 34.3 weeks in the entecavir group (P<0.001). A decrease in the HBV DNA titer was observed in all patients with active HBV replication. None of the HBV carriers in the Tacrolimus+entecavir group showed evidence of HBV reactivation. The serum creatinine and alanine aminotransferase levels remained stable in both groups. The Tacrolimus target trough concentration was 5-10 ng/mL. Conclusion: Tacrolimus combined with entecavir rapidly and effectively induced remission of HBV-GN in Chinese adults. Furthermore, Tacrolimus may have a synergistic antiviral effect with entecavir.

  9. Mucosal Tolerance Induced by an Immunodominant Peptide from Rat α3(IV)NC1 in Established Experimental Autoimmune Glomerulonephritis

    PubMed Central

    Reynolds, John; Abbott, Danielle S.; Karegli, Julieta; Evans, David J.; Pusey, Charles D.

    2009-01-01

    Experimental autoimmune glomerulonephritis (EAG), an animal model of Goodpasture’s disease, can be induced in Wistar Kyoto (WKY) rats by immunization with the noncollagenous domain of the α 3 chain of type IV collagen, α3(IV)NC1. Recent studies have identified an immunodominant peptide, pCol (24-38), from the N-terminus of rat α3(IV)NC1; this peptide contains the major B- and T-cell epitopes in EAG and can induce crescentic nephritis. In this study, we investigated the mechanisms of mucosal tolerance in EAG by examining the effects of the nasal administration of this peptide after the onset of disease. A dose-dependent effect was observed: a dose of 300 μg had no effect, a dose of 1000 μg resulted in a moderate reduction in EAG severity, and a dose of 3000 μg produced a marked reduction in EAG severity accompanied by diminished antigen-specific, T-cell proliferative responses. These results demonstrate that mucosal tolerance in EAG can be induced by nasal administration of an immunodominant peptide from the N-terminus of α3(IV)NC1 and should be of value in designing new therapeutic strategies for patients with Goodpasture’s disease and other autoimmune disorders. PMID:19406992

  10. Increased risk for lymphoma and glomerulonephritis in a closed population of cats exposed to feline leukemia virus.

    PubMed

    Francis, D P; Essex, M; Jakowski, R M; Cotter, S M; Lerer, T J; Hardy, W D

    1980-03-01

    Feline leukemia virus (FeLV)-associated diseases were observed in a household in eastern Connecticut having 134 cats over a period of five and a half years. FeLV-positive cats had a much higher mortality rate (34.6 deaths per 1000 cat-months of follow-up) than did FeLV-negative cats (8.9 deaths per 1000 cat-months of follow-up). The leading cause of death was glomerulonephritis followed by lymphoma. The relative risk for virus-positive cats as compared to virus-negative cats for the two diseases was 9.9 and 9.6, respectively. The major risk factors for the development of lymphoma were virus positivity and low antibody titer to the feline oncornavirus-associated cell membrane antigen (FOCMA). No significant differences in cancer incidence were seen between the two major breeds (Abyssinian and Burmese) in the household. An older age at arrival in the house decreased death rates for all causes in the household, but it did not significantly affect death rates from lymphoma, although there was a positive trend. PMID:6244730

  11. The Effects of a Selective CK2 Inhibitor on Anti-glomerular Basement Membrane Glomerulonephritis in Rats.

    PubMed

    Shi, Junfeng; Liu, Ning; Xiao, Ying; Takei, Yoshinori; Yasue, Misato; Suzuki, Yamato; Hou, Zengye; Ohno, Hiroaki; Yamada, Masateru; Fuchi, Nobuhiro; Oshida, Keiyu; Miyamoto, Yohei; Tsujimoto, Gozoh; Hirasawa, Akira

    2015-01-01

    Protein kinase CK2 ("casein kinase II") is a protein serine/threonine kinase that plays critical roles in biological processes such as cell growth, cell cycle progression, and apoptosis. So far, we have identified that one catalytic isozyme of CK2, CK2α, is over-expressed in the kidney during the progression of glomerulonephritis (GN). Moreover, we have shown that in vivo inhibition of CK2 by administration of CK2 inhibitors was effective in the treatment of experimental GN. Hence the development of potent CK2 inhibitors should be considered in therapeutic strategies for GN. In the present study we identified compound 13, a pyrazine derivative, as a potent CK2 inhibitor. By performing enzyme kinetics analysis in vitro, we characterized the inhibition of compound 13 toward each CK2 catalytic isozyme. Furthermore, in vivo, we demonstrated that compound 13 is effective in attenuating proteinuria, decreasing the enhanced level of blood urea nitrogen and serum creatinine, and ameliorating glomerular crescent formation in an experimental GN rat model. On the other hand, cellular apoptosis was detected in the rat testis following administration of compound 13. This study provides clues for new strategies for developing applicable compounds into CK2-targeted GN treatments. PMID:26328489

  12. A Sub-Arcsecond Mid-Infrared Survey of X-Ray-Selected AGN

    NASA Astrophysics Data System (ADS)

    Levenson, N. A.; Alonso-Herrero, A.; Packham, Chris; Los Piratas AGN Science Team

    2015-08-01

    Detailed studies of local active galactic nuclei (AGN) following X-ray selection yields significant measurements of the physical properties of the AGN and their host galaxies. In turn, the complete analysis of the nearby cases at high spatial resolution---to distinguish multiple physical components---and high signal-to-noise ratio informs broader surveys of more distant examples where such observations are not possible. We apply these methods in the Los Piratas survey, which emphasizes new observations at mid-infrared wavelengths obtained using CanariCam on the 10.4m Gran Telescopio Canarias. We measure intrinsic bolometric luminosity of the roughly 100 AGN in the sample using X-rays, ensuring a span of luminosity over a range of activity level (from low-ionization nuclei through Seyfert galaxies and quasars), optical type, and radio loudness. The mid-infrared observations at resolution of ~0.3arcsec correspond to typical spatial scales of 60 pc for the low-luminosity AGN and Seyferts and 400 pc for other types. We isolate the AGN emission that is reprocessed by dust in the central regions, which we model in a clumpy distribution. We distinguish this emission from the stellar contributions on larger scales. Across types, the AGN-heated dust emission is overall well-correlated with the X-ray flux, but stellar contributions can be significant on larger scales, especially at moderate AGN luminosity.

  13. A Model for Type 2 Coronal Line Forest (CLiF) AGNs

    NASA Astrophysics Data System (ADS)

    Glidden, Ana; Rose, Marvin; Elvis, Martin; McDowell, Jonathan

    2016-06-01

    We present a model for the classification of Coronal Line Forest Active Galactic Nuclei (CLiF AGNs). CLiF AGNs are of special interest due to their remarkably large number of emission lines, especially forbidden high-ionization lines (FHILs). Rose et al. suggest that their emission is dominated by reflection from the inner wall of the obscuring region rather than direct emission from the accretion disk. This makes CLiF AGNs laboratories to test AGN-torus models. Modeling an AGN as an accreting supermassive black hole surrounded by a cylinder of dust and gas, we show a relationship between the viewing angle and the revealed area of the inner wall. From the revealed area, we can determine the amount of FHIL emission at various angles. We calculate the strength of [Fe vii]λ6087 emission for a number of intermediate angles (30°, 40°, and 50°) and compare the results with the luminosity of the observed emission line from six known CLiF AGNs. We find that there is good agreement between our model and the observational results. The model also enables us to determine the relationship between the type 2:type 1 AGN fraction vs the ratio of torus height to radius, h/r.

  14. Role of the α-Glucanase Agn1p in Fission-Yeast Cell Separation

    PubMed Central

    Dekker, Nick; Speijer, Dave; Grün, Christian H.; van den Berg, Marlene; de Haan, Annett; Hochstenbach, Frans

    2004-01-01

    Cell division in the fission yeast Schizosaccharomyces pombe yields two equal-sized daughter cells. Medial fission is achieved by deposition of a primary septum flanked by two secondary septa within the dividing cell. During the final step of cell division, cell separation, the primary septum is hydrolyzed by an endo-(1,3)-β-glucanase, Eng1p. We reasoned that the cell wall material surrounding the septum, referred to here as the septum edging, also must be hydrolyzed before full separation of the daughter cells can occur. Because the septum edging contains (1,3)-α-glucan, we investigated the cellular functions of the putative (1,3)-α-glucanases Agn1p and Agn2p. Whereas agn2 deletion results in a defect in endolysis of the ascus wall, deletion of agn1 leads to clumped cells that remained attached to each other by septum-edging material. Purified Agn1p hydrolyzes (1,3)-α-glucan predominantly into pentasaccharides, indicating an endo-catalytic mode of hydrolysis. Furthermore, we show that the transcription factors Sep1p and Ace2p regulate both eng1 and agn1 expression in a cell cycle-dependent manner. We propose that Agn1p acts in concert with Eng1p to achieve efficient cell separation, thereby exposing the secondary septa as the new ends of the daughter cells. PMID:15194814

  15. The cosmic evolution of massive black holes in the Horizon-AGN simulation

    NASA Astrophysics Data System (ADS)

    Volonteri, M.; Dubois, Y.; Pichon, C.; Devriendt, J.

    2016-08-01

    We analyse the demographics of black holes (BHs) in the large-volume cosmological hydrodynamical simulation Horizon-AGN. This simulation statistically models how much gas is accreted on to BHs, traces the energy deposited into their environment and, consequently, the back-reaction of the ambient medium on BH growth. The synthetic BHs reproduce a variety of observational constraints such as the redshift evolution of the BH mass density and the mass function. Strong self-regulation via AGN feedback, weak supernova feedback, and unresolved internal processes result in a tight BH-galaxy mass correlation. Starting at z ˜ 2, tidal stripping creates a small population of BHs over-massive with respect to the halo. The fraction of galaxies hosting a central BH or an AGN increases with stellar mass. The AGN fraction agrees better with multi-wavelength studies, than single-wavelength ones, unless obscuration is taken into account. The most massive haloes present BH multiplicity, with additional BHs gained by ongoing or past mergers. In some cases, both a central and an off-centre AGN shine concurrently, producing a dual AGN. This dual AGN population dwindles with decreasing redshift, as found in observations. Specific accretion rate and Eddington ratio distributions are in good agreement with observational estimates. The BH population is dominated in turn by fast, slow, and very slow accretors, with transitions occurring at z = 3 and z = 2, respectively.

  16. The cosmic evolution of massive black holes in the Horizon-AGN simulation

    NASA Astrophysics Data System (ADS)

    Volonteri, M.; Dubois, Y.; Pichon, C.; Devriendt, J.

    2016-08-01

    We analyse the demographics of black holes (BHs) in the large-volume cosmological hydrodynamical simulation Horizon-AGN. This simulation statistically models how much gas is accreted onto BHs, traces the energy deposited into their environment and, consequently, the back-reaction of the ambient medium on BH growth. The synthetic BHs reproduce a variety of observational constraints such as the redshift evolution of the BH mass density and the mass function. Strong self-regulation via AGN feedback, weak supernova feedback, and unresolved internal processes result in a tight BH-galaxy mass correlation. Starting at z~2, tidal stripping creates a small population of BHs over-massive with respect to the halo. The fraction of galaxies hosting a central BH or an AGN increases with stellar mass. The AGN fraction agrees better with multi-wavelength studies, than single-wavelength ones, unless obscuration is taken into account. The most massive halos present BH multiplicity, with additional BHs gained by ongoing or past mergers. In some cases, both a central and an off-centre AGN shine concurrently, producing a dual AGN. This dual AGN population dwindles with decreasing redshift, as found in observations. Specific accretion rate and Eddington ratio distributions are in good agreement with observational estimates. The BH population is dominated in turn by fast, slow, and very slow accretors, with transitions occurring at z=3 and z=2 respectively.

  17. The Average 0.5-200 keV Spectrum of AGNs at 0

    NASA Astrophysics Data System (ADS)

    Ballantyne, David R.

    2013-04-01

    The X-ray spectra of AGNs span nearly three decades in energy and are comprised of many separate components: a power-law with a high energy cutoff, reflection from the accretion disk as well as distant material, and, in many cases, a soft excess. Aside from a small number of bright sources observed with BeppoSAX, the full energy range of AGN spectra has only been studied in piecemeal by a fleet of X-ray observatories that can only focus on a small part of the entire spectrum. Therefore, while catalogues of the spectral properties of hundreds of AGNs have been published in different energy bands, these results are isolated from one another and a clear picture of the broadband spectral properties of typical AGNs remains elusive. In this work, we make use of the 0 X-ray luminosity functions of AGNs in the 0.5-2 keV, 2-10 keV, 3-20 keV, 15-55 keV and 14-195 keV bands to construct the spectral model of an average AGN that can simultaneously account for all 5 luminosity functions. Enhanced iron abundances, disk reflection, and the presence or absence of the X-ray Baldwin Effect are considered, along with the traditional parameters of photon index and cutoff energy. Applications to X-ray background modelling and AGN physics are discussed.

  18. Effectiveness of WISE colour-based selection techniques to uncover obscured AGN

    NASA Astrophysics Data System (ADS)

    Mateos, S.

    2014-07-01

    We present a highly reliable and efficient mid-infrared colour-based selection technique for luminous active galactic nuclei (AGN) using the Wide-field Infrared Survey Explorer (WISE) survey. Our technique is designed to identify objects with red mid-infrared power-law spectral energy distributions. We studied the dependency of our mid-infrared selection on the AGN intrinsic luminosity and the effectiveness of our technique to uncover obscured AGN missed in X-ray surveys. To do so we used two samples of luminous AGN independently selected in hard X-ray and optical surveys. We used the largest catalogue of 887 [OIII] λ5007-selected type 2 quasars (QSO2s) at z<~0.83 in the literature from the Sloan Digital Sky Survey (SDSS), and the 258 hard (>4.5 keV) X-ray-selected AGN from the Bright Ultrahard XMM-Newton Survey (BUXS). The effectiveness of our mid-infrared selection technique increases with the AGN luminosity. At high luminosities and at least up to z~1 our technique is very effective at identifying both Compton-thin and Compton-thick AGN.

  19. Binary Black Holes, Accretion Disks and Relativistic Jets: Photocenters of Nearby AGN and Quasars

    NASA Technical Reports Server (NTRS)

    Wehrle, Ann E.; Jones, Dayton L.; Meier, David L.; Piner, B. Glenn; Unwin, Stephen C.

    2004-01-01

    One of the most challenging questions in astronomy today is to understand the origin, structure, and evolution of the central engines in the nuclei of quasars and active galaxies (AGNs). The favoured theory involves the activation of relativistic jets from the fueling of a supermassive black hole through an accretion disk. In some AGN an outer optically thick, dusty torus is seen orbiting the black hole system. This torus is probably related to an inner accretion disk - black hole system that forms the actual powerhouse of the AGN. In radio-loud AGN two oppositely-directed radio jets are ejected perpendicular to the torus/disk system. Although there is a wealth of observational data on AGN, some very basic questions have not been definitively answered. The Space Interferometry Mission (SIM) will address the following three key questions about AGN. 1) Does the most compact optical emission from an AGN come from an accretion disk or from a relativistic jet? 2) Does the separation of the radio core and optical photocenter of the quasars used for the reference frame tie, change on the timescales of their photometric variability, or is the separation stable at the level of a few microarcseconds? 3) Do the cores of galaxies harbor binary supermassive black holes remaining from galaxy mergers? It is not known whether such mergers are common, and whether binaries would persist for a significant time.

  20. On the variable nature of low luminosity AGN

    NASA Astrophysics Data System (ADS)

    Hernandez-Garcia, Lorena

    2015-09-01

    X-ray variability is very common in active galactic nuclei (AGN), but it is still unknown if these variations occur similarly in different families of AGN. The main purpose of this work is to disentangle the true structure of low ionization nuclear emission line regions (LINERs) compared to Seyfert 2s by the study of their X-ray variations. We assembled the X-ray spectral properties, as well as the X-ray variability pattern(s), which were obtained from simultaneous spectral fittings and letting different parameters to vary in the model, derived from our previous analyses (Hernández-García et al. 2013, 2014, 2015). We find that Seyfert 2s need more complex models to fit their spectra than LINERs. Among the spectral parameters, major differences are observed in the soft (0.5-2 keV) and hard (2-10 keV) X-ray luminosities, and the Eddington ratios, which are higher in Seyfert 2s. Differences are observed also in the hard column densities, temperatures, and black hole masses, although less significant. Short-term X-ray variations cannot be claimed, while long-term variability is very common in both families. An exception is found for Compton-thick sources, which do not vary, most probably because the AGN is not accesible in the 0.5--10 keV energy band. The changes are mostly related with variations in the nuclear continuum, but other patterns of variability show that variations in the absorbers (more common in Seyfert 2s) and at soft energies can be present in a few cases. Variations at UV frequencies are observed only in LINER nuclei. The X-ray variations occur similarly in LINERs and Seyfert 2s, i.e., they are related to the nuclear continuum, although they might have different accretion mechanisms, being more efficient in Seyfert 2s. Absorption variations and changing-look sources are not usually observed in LINERs. However, UV nuclear variations are common among LINERs, indicating an unobstructed view of the inner disc where the UV emission might take place. We

  1. TORUS2015: The AGN unification scheme after 30 years

    NASA Astrophysics Data System (ADS)

    Gandhi, P.; Hoenig, S. F.

    2015-09-01

    The torus paradigm has proved to be remarkably successful at unifying the observed zoo of active galaxy (AGN) classes, despite having many manifest holes. The field is still data-driven with novel observational results at multiple wavelengths emerging rapidly. We are only now beginning to map out the structure of dusty gas feeding and obscuring AGN, and to model its evolution in galaxy growth. But these have also brought out several apparently contradictory results which must hold the key to future progress. As we celebrate 30 years of the paradigm, this is the perfect time to draw together our current knowledge and reassess the state of the field. This will be an international workshop at the University of Southampton, UK, with the objective of laying out the major challenges to the field and paving future research directions. Our hope is to facilitate plenty of informal discussions between multiwavelength observers and theorists, addressing some key issues: * What is the main driver in the unification scheme? What are the roles of orientation, mass accretion rate and feedback? * What is the nature and structure of gas and dust in the torus? Do we have a self-consistent picture across multiple wavelengths? * How critical is the role of the torus as an interface between small nuclear scales and large galactic scales? Does galaxy evolution necessarily require tori? * How close are we to self-consistently simulating nuclear activity including AGN feeding and nuclear star-formation? Workshop Rationale The three themes of accretion, orientation, and evolution will be covered through invited and solicited contributions. Different to other conferences, we are building each session around some key papers that have shaped the field or those with great future potential to do so. We specifically pit competing ideas against each other to help painting a realistic picture of the state-of-the-art. Each session will end with discussion rounds delving into important future

  2. AGN Clustering in the Local Universe: An Unbiased Picture from Swift-BAT

    SciTech Connect

    Cappelluti, N.; Ajello, M.; Burlon, D.; Krumpe, M.; Miyaji, T.; Bonoli, S.; Greiner, J.; /Garching, Max Planck Inst., MPE

    2011-08-11

    We present the clustering measurement of hard X-ray selected AGN in the local Universe. We used a sample of 199 sources spectroscopically confirmed detected by Swift-BAT in its 15-55 keV all-sky survey. We measured the real space projected auto-correlation function and detected a signal significant on projected scales lower than 200 Mpc/h. We measured a correlation length of r{sub 0} = 5.56{sup +0.49}{sub -0.43} Mpc/h and a slope {gamma} = 1.64{sup -0.08}{sub -0.07}. We also measured the auto-correlation function of Tyep I and Type II AGN and found higher correlation length for Type I AGN. We have a marginal evidence of luminosity dependent clustering of AGN, as we detected a larger correlation length of luminous AGN than that of low luminosity sources. The corresponding typical host DM halo masses of Swift-BAT are {approx} log(M{sub DMH) {approx} 12-14 h{sup -1}M/M{sub {circle_dot}} which is the typical mass of a galaxy group. We estimated that the local AGN population has a typical lifetime {tau}{sub AGN} {approx}0.7 Gyr, it is powered by SMBH with mass M{sub BH} {approx}1-10x10{sup 8} M{sub {circle_dot}} and accreting with very low efficiency, log({epsilon}){approx}-2.0>. We also conclude that local AGN galaxies are typically red-massive galaxies with stellar mass of the order 2-80x10{sup 10} h{sup -1}M{sub {circle_dot}}. We compared our results with clustering predictions of merger-driven AGN triggering models and found a good agreement.

  3. Dust Obscured AGN are Masquerading as Star Formation in the Early Universe

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, Allison; Pope, Alexandra; Sajina, Anna; Roebuck, Eric

    2016-01-01

    The buildup of stellar and black hole mass peaked during z=1-3, making this a key epoch for understanding how the interplay of star formation and an active galactic nucleus (AGN) drive galaxy evolution. IR luminous galaxies, which are massive and heavily dust obscured (LIR > 1011 Lsun), dominate the stellar growth during this era, and many are harboring a hidden AGN. I have quantified the contribution of AGN heating to the infrared emission of 343 IR luminous galaxies from z=0.5-2.8 using Spitzer mid-IR spectroscopy, available for every source, making this an unprecedented sample. I classify sources as star forming galaxies, AGN, or composites based on the presence of mid-IR continuum emission due to a dusty torus. My findings are: 1) Surprisingly, 60% of IR luminous galaxies show signs of some dust heating emanating from an AGN. I quantify the far-IR emission using deep Herschel imaging and find that the strength of mid-IR AGN emission is tightly correlated with the total contribution of an AGN to LIR, which has important consequences for calculating star formation rates in dusty high redshift galaxies. I demonstrate techniques to remove the contribution of AGN to LIR when mid-IR spectroscopy is available and when only limited photometry is available. 2) The composites are a separate class of galaxy which show a true mix of star formation and AGN activity in their mid- and far-IR emission. Because of dust obscuration, this activity is largely undetected at other wavelengths. This composite population is important for understanding galaxy evolution and makes up at least 30% of the deepest IR selected samples. I underscore the importance of considering composite galaxies separately in studies of star formation and black hole growth at high redshift.

  4. Unravelling ICM Physics and AGN Feedback with Deep Chandra Observations of NGC 5813

    NASA Astrophysics Data System (ADS)

    Randall, Scott; Nulsen, Paul; Jones, Christine; Forman, William; Clarke, Tracy

    2015-09-01

    We present results based on very deep (650 ks) Chandra observations of the galaxy group NGC 5813. This system shows three pairs of collinear cavities, with each pair associated with an elliptical AGN outburstshock. Due to the relatively regular morphology of this system, and the unique unambiguous detection of three distinct AGN outburstshocks, it is particularly well-suited for the study of AGN feedbackand the AGN outburst history. The implied mean kinetic power is roughly the same for each outburst, demonstrating that the average AGN kinetic luminosity can remain stable over long timescales (roughly 50Myr). The two older outbursts have larger, roughly equal total energies as compared with the youngest outburst, implying that the youngest outburst is ongoing. We find that the radiative cooling rate and the mean shock heating rate of the gas are well balanced at each shock front, suggesting that AGN outburst shock heating alone is sufficient to offset cooling and establish AGN/ICM feedback within at least the central 30 kpc. This heating takes place roughly isotropically and most strongly at small radii, as is required for feedback to operate. We suggest that shock heating may play a significant role in AGN feedback at smaller radii in other systems, where weak shocks are more difficult to detect. We find non-zero shockfront widths that are too large to be explained by particle diffusion. Instead, all measured widths are consistent with shock broadening due to propagation through a turbulent ICM with a mean turbulent speed of roughly 70 km/s. Significant contributions to our understanding of AGN feedback and ICM physics, partially via studies similar to the one described here, will be one of the major achievements of the Athena mission.

  5. Constraining AGN triggering mechanisms through the clustering analysis of active black holes

    NASA Astrophysics Data System (ADS)

    Gatti, M.; Shankar, F.; Bouillot, V.; Menci, N.; Lamastra, A.; Hirschmann, M.; Fiore, F.

    2016-02-01

    The triggering mechanisms for active galactic nuclei (AGN) are still debated. Some of the most popular ones include galaxy interactions (IT) and disc instabilities (DIs). Using an advanced semi-analytic model (SAM) of galaxy formation, coupled to accurate halo occupation distribution modelling, we investigate the imprint left by each separate triggering process on the clustering strength of AGN at small and large scales. Our main results are as follows: (i) DIs, irrespective of their exact implementation in the SAM, tend to fall short in triggering AGN activity in galaxies at the centre of haloes with Mh > 1013.5 h-1 M⊙. On the contrary, the IT scenario predicts abundance of active central galaxies that generally agrees well with observations at every halo mass. (ii) The relative number of satellite AGN in DIs at intermediate-to-low luminosities is always significantly higher than in IT models, especially in groups and clusters. The low AGN satellite fraction predicted for the IT scenario might suggest that different feeding modes could simultaneously contribute to the triggering of satellite AGN. (iii) Both scenarios are quite degenerate in matching large-scale clustering measurements, suggesting that the sole average bias might not be an effective observational constraint. (iv) Our analysis suggests the presence of both a mild luminosity and a more consistent redshift dependence in the AGN clustering, with AGN inhabiting progressively less massive dark matter haloes as the redshift increases. We also discuss the impact of different observational selection cuts in measuring AGN clustering, including possible discrepancies between optical and X-ray surveys.

  6. The Star-Forming Properties of an Ultra-Hard X-ray Selected Sample of AGN

    NASA Astrophysics Data System (ADS)

    Shimizu, Thomas Taro; Mushotzky, Richard; Melendez, Marcio; Koss, Michael

    2015-08-01

    We present results from our Herschel follow-up survey of the Swift/BAT AGN 58 month catalog. Using the PACS and SPIRE instruments, 313 AGN were imaged at 5 far-infrared (FIR) wavelengths (70, 160, 250, 350, and 500 μm) producing the largest and most complete FIR catalog of local AGN. We combine our FIR photometry with archival mid-infrared photometry to form broadband spectral energy distributions (SEDs) that for the first time reach into the sub-millimeter regime. We fit these SEDs with several models to determine the star-forming properties of the host galaxies such as star-formation rate (SFR), IR luminosity, dust temperature, and dust mass and measure their relationship with various AGN properties such as X-ray luminosity, Eddington ratio, black hole mass, and column density. We find a weak dependence of the global SFR on the AGN strength indicating either the AGN has little influence on star formation over the entire galaxy or that the variability of the AGN on short timescales washes away any correlation between star formation and the AGN. Comparing the BAT AGN to a sample of normal star-forming galaxies on the “main sequence”, we find the BAT AGN systematically have decreased levels of specific SFR (sSFR = SFR/stellar mass). This is possibly indirect evidence that the AGN has suppressed star-formation in its host galaxy. Analysis of the FIR images themselves reveals that many of the BAT AGN are compact which leads to increased levels of SFR surface density, high enough for starburst driven winds. Finally, we show the 70 μm luminosity can be heavily contaminated by AGN emission and should not be used as a SFR indicator for AGN host galaxies.

  7. The INTEGRAL/IBIS AGN catalogue - I. X-ray absorption properties versus optical classification

    NASA Astrophysics Data System (ADS)

    Malizia, A.; Bassani, L.; Bazzano, A.; Bird, A. J.; Masetti, N.; Panessa, F.; Stephen, J. B.; Ubertini, P.

    2012-11-01

    In this work we present the most comprehensive INTEGRAL active galactic nucleus (AGN) sample. It lists 272 AGN for which we have secure optical identifications, precise optical spectroscopy and measured redshift values plus X-ray spectral information, i.e. 2-10 and 20-100 keV fluxes plus column density. Here we mainly use this sample to study the absorption properties of active galaxies, to probe new AGN classes and to test the AGN unification scheme. We find that half (48 per cent) of the sample is absorbed, while the fraction of Compton-thick AGN is small (˜7 per cent). In line with our previous analysis, we have however shown that when the bias towards heavily absorbed objects which are lost if weak and at large distance is removed, as it is possible in the local Universe, the above fractions increase to become 80 and 17 per cent. We also find that absorption is a function of source luminosity, which implies some evolution in the obscuration properties of AGN. A few peculiar classes, so far poorly studied in the hard X-ray band, have been detected and studied for the first time such as 5 X-ray bright optically normal galaxies, 5 type 2 QSOs and 11 low-ionization nuclear emission regions. In terms of optical classification, our sample contains 57 per cent of type 1 and 43 per cent of type 2 AGN; this subdivision is similar to that found in X-rays if unabsorbed versus absorbed objects are considered, suggesting that the match between optical and X-ray classifications is overall good. Only a small percentage of sources (12 per cent) does not fulfil the expectation of the unified theory as we find 22 type 1 AGN which are absorbed and 10 type 2 AGN which are unabsorbed. Studying in depth these outliers we found that most of the absorbed type 1 AGN have X-ray spectra characterized by either complex or warm/ionized absorption more likely due to ionized gas located in an accretion disc wind or in the biconical structure associated with the central nucleus, therefore

  8. The host galaxies and narrow-line regions of four double-peaked [OIII] AGNs

    SciTech Connect

    Villforth, Carolin; Hamann, Fred

    2015-03-01

    Major gas-rich mergers of galaxies are expected to play an important role in triggering and fueling luminous active galactic nuclei (AGNs). The mechanism of AGN fueling during mergers, however, remains poorly understood. We present deep multi-band (u/r/z) imaging and long-slit spectroscopy of four double-peaked [OIII] emitting AGNs. This class of object is likely associated with either kiloparsec-separated binary AGNs or final stage major mergers, although AGNs with complex narrow-line regions (NLRs) are known contaminants. Such objects are of interest since they represent the onset of AGN activity during the merger process. Three of the four double-peaked [OIII] emitters studied have been confirmed as major mergers using near-infrared imaging and one is a confirmed X-ray binary AGN. All AGNs are luminous, radio-quiet to radio-intermediate, and have redshifts of 0.1AGN suggests that the merger of a binary black hole can take longer than 1 Gyr. All AGNs hosted by merging galaxies have companions at distances ⩽150 kpc. The NLRs have large sizes (10 kpc < r < 100 kpc) and consist of compact clumps with considerable relative velocities between components (∼200–650 km s{sup −1}). We detect broad, predominantly blue, wings with velocities up to ∼1500 km s{sup −1} in [OIII], indicative of powerful outflows. The outflows are compact (<5 kpc) and co-spatial with nuclear regions showing considerable reddening, consistent with enhanced star formation. One source shows an offset between gas and stellar kinematics, consistent with either a bipolar flow or a counter-rotating gas disk. In all other sources, the ionized gas

  9. Is There an Obscured AGN in the Normal Galaxy IRASF01063-8034

    NASA Technical Reports Server (NTRS)

    Greenhill, Lincoln J.

    2005-01-01

    The XMM target for this program is ostensibly a "normal" galaxy, but the presence of water maser emission indicated that it may be an obscured AGN. Our primary goal is to test this hypothesis; detection hard X-ray emission and a reflection-dominated spectrum would indicate an AGN is present. Demonstration that the local universe contains obscured AGN is important to constraining models of the hard cosmic X-ray background, as is identification of efficient methods to locate them (e.g., ground-based detection of maser emission at microwave frequencies).

  10. The Vertical Structure of Nuclear Starburst Disks: Testing a Model of AGN Obscuration

    NASA Astrophysics Data System (ADS)

    Ballantyne, David R.; Gohil, Raj

    2016-04-01

    Nuclear starburst disks are Eddington-limited, radiation pressure supported disks that may be active in the nuclear environment of active galaxies (ULIRGS and AGNs). Earlier analytical models suggested that, under certain conditions, these disks may be geometrically thick on pc-scales, and thus could be a viable source for AGN obscuration, partcularly at z≤1, when gas factions in galaxies are still significant. Here, we present early results from numerical 2D models of nuclear starburst disks where the vertical structure is calculated explicitly from solving the hydrostatic balance and radiative transfer equations. We quantitatively assess under which conditions the starburst disk may present substantial obscuring columns for AGN observations.

  11. X-ray and Optical Properties of an Unbiased Sample of Local AGN

    NASA Astrophysics Data System (ADS)

    Winter, Lisa M.; Mushotzky, R.; Tueller, J.; Lewis, K.; Reynolds, C.

    2007-12-01

    The SWIFT Burst Alert Telescope (BAT), while not focused on a Gamma-ray burst, conducts an all-sky survey in the 14 - 195 keV band. After the first 9 months, the BAT has detected a sample of 153 local (z ˜ 0.03) AGN at a flux limit of a few times 10-11 erg/s/cm-2 (Tueller et al. 2007). Since the AGN were detected at very high X-ray energies, they are an unbiased sample towards column densities below 1025 cm-2. We present the X-ray and optical properties of a sample of the BAT AGN.

  12. VizieR Online Data Catalog: RM AGNs accretion rates and BH masses (Du+, 2016)

    NASA Astrophysics Data System (ADS)

    Du, P.; Wang, J.-M.; Hu, C.; Ho, L. C.; Li, Y.-R.; Bai, J.-M.

    2016-05-01

    We select all AGNs with reverberation mapping (RM) data (here only broad Hβ line), which yield robust BH mass estimates needed for our analysis. All RM AGNs before 2013 are summarized by Bentz et al. (2013ApJ...767..149B). Our project to search for super-Eddington accreting massive black holes (SEAMBHs) has monitored about 25 candidates and successfully measured Hβ lags ({tau}Hβ) in 14 AGNs to date (Du et al. 2015, J/ApJ/806/22) and other five objects monitored between 2014 and 2015 (to be submitted). See section 2 for further explanations. (2 data files).

  13. Relativistic Effects on Reflection X-ray Spectra of AGN

    SciTech Connect

    Lee, Khee-Gan; Fuerst, Steven V.; Brandwardi-Raymond, Graziella; Wu, Kinwah; Crowley, Oliver; /University Coll. London

    2007-01-05

    We have calculated the reflection component of the X-ray spectra of active galactic nuclei (AGN) and shown that they can be significantly modified by the relativistic motion of the accretion flow and various gravitational effects of the central black hole. The absorption edges in the reflection spectra suffer severe energy shifts and smearing. The degree of distortion depends on the system parameters, and the dependence is stronger for some parameters such as the inner radius of the accretion disk and the disk viewing inclination angles. The relativistic effects are significant and are observable. Improper treatment of the reflection component of the X-ray continuum in spectral fittings will give rise to spurious line-like features, which will mimic the fluorescent emission lines and mask the relativistic signatures of the lines.

  14. Jets and Outflows in Radio Galaxies: Implications for AGN Feedback

    NASA Astrophysics Data System (ADS)

    Torresi, Eleonora; Grandi, Paola; Costantini, Elisa; Palumbo, Giorgio G. C.

    One of the main debated astrophysical problems is the role of the AGN feedback in galaxy formation. It is known that massive black holes have a profound effect on the formation and evolution of galaxies, but how black holes and galaxies communicate is still an unsolved problem. For Radio Galaxies, feedback studies have mainly focused on jet/cavity systems in the most massive and X-ray luminous galaxy clusters. The recent high-resolution detection of warm absorbers in some Broad Line Radio Galaxies allow us to investigate the interplay between the nuclear engine and the surrounding medium from a different perspective. We report on the detection of warm absorbers in two Broad Line Radio Galaxies, 3C 382 and 3C 390.3, and discuss the physical and energetic properties of the absorbing gas. Finally, we attempt a comparison between radio-loud and radio-quiet outflows.

  15. Synergy Between Observations of AGN with GLAST and MAXI

    SciTech Connect

    Madejski, Grzegorz

    2002-03-25

    In five years' time we will witness the launch of two important missions developed to observe celestial sources in the high energy regime: GLAST, sensitive in the high energy {gamma}-ray band, and MAXI, the all-sky X-ray monitor. Simultaneous monitoring observations by the two instruments will be particularly valuable for variable sources, allowing cross-correlations of time series between the two bands. We present the anticipated results from such observations of active galaxies, and in particular, of the jet-dominated sub-class of AGN known as blazars. We discuss the constraints on the structure and emission processes--and in particular, on the internal shock models currently invoked to explain the particle acceleration processes in blazars--that can be derived with simultaneous {gamma}-ray and X-ray data.

  16. Fossil shell emission in dying radio loud AGNs

    NASA Astrophysics Data System (ADS)

    Kino, M.; Ito, H.; Kawakatu, N.; Orienti, M.; Nagai, H.; Wajima, K.; Itoh, R.

    2016-02-01

    We investigate shell emission associated with dying radio loud AGNs. First, based on our recent work by Ito et al. (2015), we describe the dynamical and spectral evolution of shells after stopping the jet energy injection. We find that the shell emission overwhelms that of the radio lobes soon after stopping the jet energy injection because fresh electrons are continuously supplied into the shell via the forward shock, while the radio lobes rapidly fade out without jet energy injection. We find that such fossil shells can be a new class of target sources for SKA telescope. Next, we apply the model to the nearby radio source 3C84. Then, we find that the fossil shell emission in 3C84 is less luminous in the radio band while it is bright in the TeV γ-ray band and can be detectable by CTA. Data from STELLA

  17. Optical Monitoring of Selected X-ray AGN

    NASA Astrophysics Data System (ADS)

    Phillips, V. D.; Sadun, A.; Kelly, M.; Baca, P.; Holt, J.; Galadari, A.; Nied, P.; Howard, E.; Ghosh, K.

    2001-12-01

    We present the results of microvariability studies of X-ray loud/radio quiet AGN in optical wavelengths (R band). The optical data were taken over approximately eight months at the Sommers-Bausch Observatory (U. Colorado-Boulder), and at the SARA Observatory. In addition to engaging in routine optical analysis, we investigated the extent to which these objects exhibited intra-night variability. The presence of microvariability would indicate that in addition to an accretion disk, there would also be present relativistic components such as parsec-scale jets; quiescence would indicate that long-term variability in these objects is perhaps due to accretion disk instabilities alone. The preliminary indication from our data is that there is indeed evidence of relativistic jets in this class of objects.

  18. Future requirements for X-ray monitoring of AGN

    NASA Astrophysics Data System (ADS)

    Nandra, K.

    2000-10-01

    Observations with RXTE have lead to major advances in our knowledge of the X-ray and multi-waveband variability properties of active galactic nuclei (AGN). In large part, this has been due to the fact that it has been possible to probe long time scale (months-years) variability in a systematic way. Current and future high-throughput missions will do an excellent job defining the characteristics of the short time variations. It is important, however, to make plans for longer-term monitoring in the future, given that RXTE has shown that this is how many of the important science questions can be addressed. The author is supported by NASA ADP grant NAG5-7067 to the Universities Space Research Association.

  19. IGM Heating and AGN activity in Fossil Galaxy Groups