RESUMO
There is growing concern about seismicity triggered by human activities, whereby small increases in stress bring tectonically loaded faults to failure. Examples of such activities include mining, impoundment of water, stimulation of geothermal fields, extraction of hydrocarbons and water, and the injection of water, CO2 and methane into subsurface reservoirs1. In the absence of sufficient information to understand and control the processes that trigger earthquakes, authorities have set up empirical regulatory monitoring-based frameworks with varying degrees of success2,3. Field experiments in the early 1970s at the Rangely, Colorado (USA) oil field4 suggested that seismicity might be turned on or off by cycling subsurface fluid pressure above or below a threshold. Here we report the development, testing and implementation of a multidisciplinary methodology for managing triggered seismicity using comprehensive and detailed information about the subsurface to calibrate geomechanical and earthquake source physics models. We then validate these models by comparing their predictions to subsequent observations made after calibration. We use our approach in the Val d'Agri oil field in seismically active southern Italy, demonstrating the successful management of triggered seismicity using a process-based method applied to a producing hydrocarbon field. Applying our approach elsewhere could help to manage and mitigate triggered seismicity.
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The MAP1LC3/LC3 family plays an essential role in autophagosomal biogenesis and transport. In this report, we show that the HECT family E3 ubiquitin ligase NEDD4 interacts with LC3 and is involved in autophagosomal biogenesis. NEDD4 binds to LC3 through a conserved WXXL LC3-binding motif in a region between the C2 and the WW2 domains. Knockdown of NEDD4 impaired starvation- or rapamycin-induced activation of autophagy and autophagosomal biogenesis and caused aggregates of the LC3 puncta colocalized with endoplasmic reticulum membrane markers. Electron microscopy observed gigantic deformed mitochondria in NEDD4 knockdown cells, suggesting that NEDD4 might function in mitophagy. Furthermore, SQSTM1 is ubiquitinated by NEDD4 while LC3 functions as an activator of NEDD4 ligase activity. Taken together, our studies define an important role of NEDD4 in regulation of autophagy.
Assuntos
Autofagia , Proteínas Associadas aos Microtúbulos/metabolismo , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Células A549 , Autofagossomos/metabolismo , Autofagossomos/ultraestrutura , Biomarcadores/metabolismo , Sequência Conservada , Retículo Endoplasmático/metabolismo , Técnicas de Silenciamento de Genes , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Membranas Intracelulares/metabolismo , Ligação Proteica , Domínios Proteicos , Proteína Sequestossoma-1/metabolismo , Especificidade por Substrato , UbiquitinaçãoRESUMO
The Longmen Shan mountain range, site of the devastating 12 May 2008 Wenchuan (M = 7.9) earthquake, defines the eastern margin of the Himalayan orogen and exhibits greater topographic relief than anywhere else in the Tibetan plateau. However, before the earthquake, geodetic and geologic surveys measured little shortening across the range front, inspiring a vigorous debate about the process by which the topography of the mountain belt is produced and maintained. Two endmember models have been proposed: (1) brittle crustal thickening, in which thrust faults with large amounts of slip that are rooted in the lithosphere cause uplift, and (2) crustal flow, in which low-viscosity material in the lower crust extrudes outward from the Tibetan plateau and inflates the crust north and east of the Himalayas. Here we use balanced geologic cross-sections to show that crustal shortening, structural relief, and topography are strongly correlated in the range front. This suggests that crustal shortening is a primary driver for uplift and topography of the Longmen Shan on the flanks of the plateau. The 2008 Wenchuan (M = 7.9) earthquake, which ruptured a large thrust fault along the range front causing tens of thousands of fatalities and widespread damage, is an active manifestation of this shortening process.
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The pathologic manifestations of renal diseases related to monoclonal plasma cell dyscrasia include light chain deposition disease, the AL type of amyloidosis, and myeloma cast nephropathy. Light chain deposit disease (LCDD) is an uncommon condition in which monoclonal light chains are deposited in the glomeruli, tubules, and vessels causing varying degree of damage. We report a case of LCDD coincident with fibrillary glomerulonephropathy (FGN) in a 73-yr-old man with a diagnosis of monoclonal gammopathy of undetermined significance who presented with progressive renal insufficiency and mild proteinuria. The serum kappa light chain level was markedly raised. Immunofluorescent stains showed IgG along with C3 and kappa staining in glomeruli, but lambda staining was negative. Electron microscopic studies revealed diffuse punctuate-type deposits along the subendothelial areas. There were also scattered randomly oriented fibrils with a mean fibril thickness of 15-25 nm seen mainly in the glomerular mesangium, consistent with FGN. The congo red stain was negative on the histologic section. The present case illustrates that LCDD can progress to develop FGN in a patient with monoclonal gammopathy.
Assuntos
Glomerulonefrite/complicações , Glomerulonefrite/diagnóstico , Cadeias Leves de Imunoglobulina/sangue , Cadeias Leves de Imunoglobulina/urina , Paraproteinemias/complicações , Idoso , Proteína de Bence Jones/urina , Diagnóstico Diferencial , Progressão da Doença , Glomerulonefrite/sangue , Humanos , Glomérulos Renais/patologia , Masculino , Paraproteinemias/sangueRESUMO
Sarcoglycans are originally identified in muscle for their involvement in limb-girdle muscular dystrophies. They form a multi-meric complex (alpha-, beta-, gamma-, delta-sarcoglycan) that associates with dystrophin, dystroglycan and other proteins to constitute the larger dystrophin-glycoprotein complex at the muscle membrane. Three sarcoglycan subunits (epsilon-, beta-, delta-sarcoglycan) were previously identified in Schwann cells and shown to associate with dystroglycan and a Schwann cell-specific dystrophin isoform (Dp116) at the outermost Schwann cell membrane. Currently, little is known about the exact composition and function of the sarcoglycan complex in the peripheral nervous system. In this study, we showed that the Schwann cell sarcoglycan complex consists of epsilon-, beta-, delta-sarcoglycan and the newly identified zeta-sarcoglycan subunit. The expression of sarcoglycans precedes the onset of myelination and is induced by neurons. In sarcoglycan-deficient BIO14.6 hamsters, loss of the Schwann cell sarcoglycan complex reduces the steady state levels of alpha-dystroglycan and Dp116. Ultrastructural analysis of sciatic nerves from the mutant animals revealed altered myelin sheaths and disorganized Schmidt-Lanterman incisures indicative of myelin instability. The disruption in myelin structure increased in severity with age. Nerve conduction studies also showed subtle electrophysiological abnormalities in the BIO14.6 hamsters consistent with reduced myelin stability. Together, these findings suggest an important role of sarcoglycans in the stability of peripheral nerve myelin.
Assuntos
Bainha de Mielina/química , Sarcoglicanas/fisiologia , Células de Schwann/metabolismo , Envelhecimento , Animais , Células Cultivadas , Técnicas de Cocultura , Cricetinae , Citoplasma/ultraestrutura , Estabilidade de Medicamentos , Distroglicanas/química , Distroglicanas/metabolismo , Eletrofisiologia , Masculino , Microscopia Eletrônica , Bainha de Mielina/metabolismo , Bainha de Mielina/ultraestrutura , Sistema Nervoso/fisiopatologia , Condução Nervosa , Isoformas de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Ratos , Ratos Sprague-Dawley , Sarcoglicanas/deficiência , Sarcoglicanas/metabolismo , Células de Schwann/ultraestrutura , Nervo Isquiático/ultraestrutura , Fatores de TempoRESUMO
We report 2 complicated cases of thrombotic microangiopathy with chronic features and active components. The first case was a 36-yr-old woman with positive anti-DNA antibody and possible lupus cerebritis, who developed thrombotic microangiopathy secondary to a series of syndromes, including preeclampsia and anti-phospholipid antibody syndrome. Renal biopsy revealed no evidence of lupus nephritis and her renal function returned to normal 1 week after the biopsy. The second case was a 46-yr-old man who developed thrombotic microangiopathy of unknown etiology, which led to end-stage renal disease within 6 mo. The patient received a living related-donor transplant, but thrombotic microangiopathy recurred in the donor kidney only 40 days after the renal transplantation.
Assuntos
Transplante de Rim , Rim/irrigação sanguínea , Complicações Cardiovasculares na Gravidez , Trombose/complicações , Adulto , Síndrome Antifosfolipídica/complicações , Doença Crônica , Feminino , Membrana Basal Glomerular/patologia , Humanos , Rim/patologia , Falência Renal Crônica/etiologia , Transplante de Rim/patologia , Masculino , Microcirculação , Pessoa de Meia-Idade , Gravidez , Trombocitopenia/etiologiaRESUMO
For several years proteomics research has been expected to lead to the finding of new markers that will translate into clinical tests applicable to samples such as serum, plasma and urine: so-called in vitro diagnostics (IVDs). Attempts to implement technologies applied in proteomics, in particular protein arrays and surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF MS), as IVD instruments have initiated constructive discussions on opportunities and challenges inherent in such a translation process also with respect to the use of multi-marker profiling approaches and pattern signatures in IVD. Taking into account the role that IVD plays in health care, we describe IVD requirements and needs. Subject to stringent costs versus benefit analyses, IVD has to provide reliable information about a person's condition, prognosis or risk to suffer a disease, thus supporting decisions on treatment or prevention. It is mandatory to fulfill requirements in routine IVD, including disease prevention, diagnosis, prognosis, and treatment monitoring or follow up among others. To fulfill IVD requirements, it is essential to (1) provide diagnostic tests that allow for definite and reliable diagnosis tied to a decision on interventions (prevention, treatment, or nontreatment), (2) meet stringent performance characteristics for each analyte (in particular test accuracy, including both precision of the measurement and trueness of the measurement), and (3) provide adequate diagnostic accuracy, i.e., diagnostic sensitivity and diagnostic specificity, determined by the desired positive and negative predictive values which depend on disease frequency. The fulfillment of essential IVD requirements is mandatory in the regulated environment of modern diagnostics. Addressing IVD needs at an early stage can support a timely and effective transition of findings and developments into routine diagnosis. IVD needs reflect features that are useful in clinical practice. This helps to generate acceptance and assists the implementation process. On the basis of IVD requirements and needs, we outline potential implications for clinical proteomics focused on applied research activities.
Assuntos
Diagnóstico , Técnicas de Diagnóstico Molecular , Proteômica , Tomada de Decisões , Humanos , Espectrometria de Massas/métodos , Valor Preditivo dos Testes , Proteômica/instrumentação , Proteômica/métodos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
We report the case of a 46-yr-old man with a 16-yr history of type I diabetes mellitus who developed rapid onset of nephrotic syndrome. Renal biopsy revealed diabetic nephropathy, characterized by thickened glomerular basement membranes (GBM), mild nodular glomerulosclerosis, and focal arteriolar hyalinization. Immunofluorescent (IF) studies showed strong granular IgM staining along glomerular loops, with subepithelial and intramembranous immune complex deposits along glomerular capillary loops demonstrated by electron microscopy (EM). These findings are consistent with membranous glomerulopathy with IgM as the predominant immunoglobulin. In addition, there were large aggregates of electron-dense material composed of numerous ring or spherical particles, ranging from 200 to 400 nm, in Bowman's space, which corresponded to eosinophilic aggregates on light microscopy (LM) and strong IgM stained materials by IF studies.
Assuntos
Nefropatias Diabéticas/diagnóstico , Glomerulonefrite Membranosa/diagnóstico , Imunoglobulina M/imunologia , Nefropatias Diabéticas/imunologia , Glomerulonefrite Membranosa/imunologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Transplantation of kidneys with pre-existing glomerulonephritis (GN) has rarely been reported. Little is known of the subsequent evolution of donor pathology in the recipient. We report a transplant using a donor with systemic lupus erythematosus (SLE) and a history of remote acute renal failure but normal renal function at death. Although the screening harvest biopsy was unremarkable, time zero post-implantation renal biopsy showed evidence of lupus nephritis (LN). Sequential protocol biopsies demonstrated gradual resolution of the donor pathology, and renal function was stable despite severe cardiac disease in the recipient. Studies examining the role of functional and biopsy data on outcomes in expanded criteria renal transplantation are reviewed, and the limits of guidance from use of this data are discussed. Pre-existing mild GN may not be an absolute donor exclusion for candidates willing to accept expanded criteria donors. Use of expanded pool kidneys should be guided by functional, biopsy and demographic information, as no single factor alone predicts outcome.
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Falência Renal Crônica/cirurgia , Transplante de Rim , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/métodos , Injúria Renal Aguda , Seguimentos , Humanos , Transplante de Rim/efeitos adversos , Nefrite Lúpica/etiologia , Masculino , Prontuários Médicos , Pessoa de Meia-IdadeRESUMO
Intracellular inclusions in lymphoproliferative disorders are not common. Multiple different types of inclusions have been reported in chronic lymphocytic leukemia (CLL), including vacuoles, crystals, and pseudocrystals. Most of the reported cases were seen in the bone marrow lymphocytes, and the majority of these on electron microscopy. We report a case of long-standing CLL with no therapy that had filamentous cytoplasmic inclusions in the peripheral blood that were readily seen by light microscopy. Electron microscopy demonstrated dilated cisternae of the rough endoplasmic reticulum filled with amorphous electron-dense material. By immunofluorescence, the material proved to be immunoglobulin G-lambda deposits. The immunophenotype had the typical CLL pattern with positive staining with CD19, CD5, and CD23, and low-density CD20 staining; however, it also had unusual staining with CD25 and intermediate-intensity staining with CD22.
Assuntos
Citoplasma/ultraestrutura , Corpos de Inclusão/ultraestrutura , Leucemia Linfocítica Crônica de Células B/sangue , Leucemia Linfocítica Crônica de Células B/patologia , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/análise , Antígenos CD/imunologia , Feminino , Citometria de Fluxo/métodos , Humanos , Imunoglobulina G/ultraestrutura , Cadeias lambda de Imunoglobulina/ultraestrutura , Imunofenotipagem/métodos , Microscopia Eletrônica/métodos , Receptores de IgE/análise , Receptores de IgE/imunologia , Receptores de Interleucina-2/análise , Receptores de Interleucina-2/imunologiaRESUMO
Borehole data from young sediments folded above the Puente Hills blind thrust fault beneath Los Angeles reveal that the folding extends to the surface as a discrete zone (=145 meters wide). Buried fold scarps within an upward- narrowing zone of deformation, which extends from the upward termination of the thrust ramp at 3 kilometers depth to the surface, document the occurrence of at least four large (moment-magnitude 7.2 to 7.5) earthquakes on this fault during the past 11,000 years. Future events of this type pose a seismic hazard to metropolitan Los Angeles. Moreover, the methods developed in this study can be used to refine seismic hazard assessments of blind thrusts in other metropolitan regions.