19 research outputs found

    Distinguishing grade I meningioma from higher grade meningiomas without biopsy

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    BACKGROUND: Many meningiomas are identified by imaging and followed, with an assumption that they are WHO Grade I tumors. The purpose of our investigation is to find clinical or imaging predictors of WHO Grade II/III tumors to distinguish them from Grade I meningiomas. METHODS: Patients with a pathologic diagnosis of meningioma from 2002-2009 were included if they had pre-operative MRI studies and pathology for review. A Neuro-Pathologist reviewed and classified all tumors by WHO 2007. All Brain MRI imaging was reviewed by a Neuro-radiologist. Pathology and Radiology reviews were blinded from each other and clinical course. Recursive partitioning was used to create predictive models for identifying meningioma grades. RESULTS: Factors significantly correlating with a diagnosis of WHO Grade II-III tumors in univariate analysis: prior CVA (p = 0.005), CABG (p = 0.010), paresis (p = 0.008), vascularity index = 4/4: (p = 0.009), convexity vs other (p = 0.014), metabolic syndrome (p = 0.025), non-skull base (p = 0.041) and non-postmenopausal female (p = 0.045). Recursive partitioning analysis identified four categories: 1. prior CVA, 2. vascular index (vi) = 4 (no CVA), 3. premenopausal or male, vi \u3c 4, no CVA. 4. Postmenopausal, vi \u3c 4, no CVA with corresponding rates of 73, 54, 35 and 10% of being Grade II-III meningiomas. CONCLUSIONS: Meningioma patients with prior CVA and those grade 4/4 vascularity are the most likely to have WHO Grade II-III tumors while post-menopausal women without these features are the most likely to have Grade I meningiomas. Further study of the associations of clinical and imaging factors with grade and clinical behavior are needed to better predict behavior of these tumors without biopsy

    R1507, an Anti-Insulin-Like Growth Factor-1 Receptor (IGF-1R) Antibody, and EWS/FLI-1 siRNA in Ewing's Sarcoma: Convergence at the IGF/IGFR/Akt Axis

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    A subset of patients with Ewing's sarcoma responds to anti-insulin-like growth factor-1 receptor (IGF-1R) antibodies. Mechanisms of sensitivity and resistance are unknown. We investigated whether an anti-IGF-1R antibody acts via a pathway that could also be suppressed by small interfering (si) RNA against the EWS/FLI-1 fusion protein, the hallmark of Ewing's sarcoma. The growth of two Ewing's sarcoma cell lines (TC-32 and TC-71) was inhibited by the fully human anti-IGF-1R antibody, R1507 (clonogenic and MTT assays). TC-32 and TC-71 cells express high levels of IGF-2, while RD-ES and A4573 Ewing's cell lines, which were less responsive to R1507 in our assays, express low or undetectable IGF-2, respectively. TC-71 cells also expressed high levels of IGF-1R, and R1507 decreased steady-state levels of this receptor by internalization/degradation, an effect which was associated with a decrease in p-IGF-1R, p-IRS-1, and p-Akt. EWS/FLI-1 siRNA also decreased p-Akt, due to its ability to increase IGF-BP3 levels and subsequently decrease IGF-1 and IGF-2 levels, thus inhibiting signaling through p-IGF-1R. This inhibition correlated with growth suppression and apoptosis. The attenuation of Akt activation was confirmed in TC-71 and HEK-293 (human embryonic kidney) cells by transfecting them with IGF-1R siRNA. We conclude that antibodies and siRNA to IGF-1R, as well as siRNA to EWS/FLI-1, act via intersecting IGF/IGF-1R signals that suppress a common point in this pathway, namely the phosphorylation of Akt

    Subdominant/Cryptic CD8 T Cell Epitopes Contribute to Resistance against Experimental Infection with a Human Protozoan Parasite

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    During adaptive immune response, pathogen-specific CD8+ T cells recognize preferentially a small number of epitopes, a phenomenon known as immunodominance. Its biological implications during natural or vaccine-induced immune responses are still unclear. Earlier, we have shown that during experimental infection, the human intracellular pathogen Trypanosoma cruzi restricts the repertoire of CD8+ T cells generating strong immunodominance. We hypothesized that this phenomenon could be a mechanism used by the parasite to reduce the breath and magnitude of the immune response, favoring parasitism, and thus that artificially broadening the T cell repertoire could favor the host. Here, we confirmed our previous observation by showing that CD8+ T cells of H-2a infected mice recognized a single epitope of an immunodominant antigen of the trans-sialidase super-family. In sharp contrast, CD8+ T cells from mice immunized with recombinant genetic vaccines (plasmid DNA and adenovirus) expressing this same T. cruzi antigen recognized, in addition to the immunodominant epitope, two other subdominant epitopes. This unexpected observation allowed us to test the protective role of the immune response to subdominant epitopes. This was accomplished by genetic vaccination of mice with mutated genes that did not express a functional immunodominant epitope. We found that these mice developed immune responses directed solely to the subdominant/cryptic CD8 T cell epitopes and a significant degree of protective immunity against infection mediated by CD8+ T cells. We concluded that artificially broadening the T cell repertoire contributes to host resistance against infection, a finding that has implications for the host-parasite relationship and vaccine development

    Dietary supplementation with the tribomechanically activated zeolite clinoptilolite in immunodeficiency: effects on the immune system

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    Natural zeolites are crystalline aluminosilicates with unique adsorption, cation-exchange, and catalytic properties that have multiple uses in industry and agriculture. TMAZ, a natural zeolite clinoptilolite with enhanced physicochemical properties, is the basis of the dietary supplements Megamin and Lycopenomin, which have demonstrated antioxidant activity in humans. The aim of this prospective, open, and controlled parallel-group study was to investigate the effects of supplementation with TMAZ on the cellular immune system in patients undergoing treatment for immunodeficiency disorder. A total of 61 patients were administered daily TMAZ doses of 1.2 g (Lycopenomin) and 3.6 g (Megamin) for 6 to 8 weeks, during which the patients' primary medical therapy was continued unchanged. Blood and lymphocyte counts were performed at baseline and at the end of the study. Blood count parameters were not relevantly affected in either of the two treatment groups. Megamin administration resulted in significantly increased CD4+, CD19+, and HLA-DR+ lymphocyte counts and a significantly decreased CD56+ cell count. Lycopenomin was associated with an increased CD3+ cell count and a decreased CD56+ lymphocyte count. No adverse reactions to the treatments were observed

    Transmembrane helix 12 modulates progression of the ATP catalytic cycle in ABCB1

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    Understanding the process that underlies multidrug recognition and efflux by P-glycoprotein (ABCB1) remains a key biological challenge. Structural data have recently become available for the murine and Caenorhabditis elegans homologues of ABCB1; however all structures were obtained in the absence of nucleotide. A feature of these structures was the presence of a central cavity that is inaccessible from the extracellular face of the protein. To determine the conformational dynamics of this region several residues in transmembrane helices TM6 (331, 343 and 354) and TM12 (980) were mutated to cysteine. Based upon structural predictions, these residues are proposed to line, or reside proximal to, the central cavity. The mutant isoforms were labelled with a paramagnetic probe enabling the application of EPR spectroscopic methods. Power saturation EPR spectra were recorded in the presence of hydrophobic (O2 ) or hydrophilic (NiEDDA) quenching agents to study the local environment of each residue. ABCB1 was trapped in both its nucleotide-bound and post-hydrolytic conformations and EPR spectra were again recorded in the presence and absence of quenching agents. The EPR line shapes provide information on the movements of these residues within TM6 and TM12 during ATP hydrolysis. Rationalization of the data with molecular dynamic simulations indicates that the cavity is converted to a configuration open to the aqueous phase following nucleotide binding, thereby suggesting alternating access to the cavity on opposite sides of the membrane during translocation

    Sixty years of global progress in managed aquifer recharge

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    The last 60 years has seen unprecedented groundwater extraction and overdraft as well as development of new technologies for water treatment that together drive the advance in intentional groundwater replenishment known as managed aquifer recharge (MAR). This paper is the first known attempt to quantify the volume of MAR at global scale, and to illustrate the advancement of all the major types of MAR and relate these to research and regulatory advancements. Faced with changing climate and rising intensity of climate extremes, MAR is an increasingly important water management strategy, alongside demand management, to maintain, enhance and secure stressed groundwater systems and to protect and improve water quality. During this time, scientific research—on hydraulic design of facilities, tracer studies, managing clogging, recovery efficiency and water quality changes in aquifers—has underpinned practical improvements in MAR and has had broader benefits in hydrogeology. Recharge wells have greatly accelerated recharge, particularly in urban areas and for mine water management. In recent years, research into governance, operating practices, reliability, economics, risk assessment and public acceptance of MAR has been undertaken. Since the 1960s, implementation of MAR has accelerated at a rate of 5%/year, but is not keeping pace with increasing groundwater extraction. Currently, MAR has reached an estimated 10 km3/year, ~2.4% of groundwater extraction in countries reporting MAR (or ~1.0% of global groundwater extraction). MAR is likely to exceed 10% of global extraction, based on experience where MAR is more advanced, to sustain quantity, reliability and quality of water supplies

    Sixty years of global progress in managed aquifer recharge

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    Sessanta anni di progressi a livello globale nella ricarica delle falde acquifere in condizioni controllate Riassunto Gli ultimi 60 anni sono stati testimoni di prelievi e fenomeni di sovrasfruttamento delle falde senza precedenti, come pure dello sviluppo di nuove tecnologie per il trattamento delle acque. Questi fattori hanno guidato i progressi nelle applicazioni della ricarica intenzionale degli acquiferi, nota in lingua inglese come managed aquifer recharge – MAR (in italiano tradotto in “ricarica delle falde in condizioni controllate”). Questo articolo è il primo tentativo conosciuto dagli Autori che ha l’obiettivo di quantificare a scala globale il volume prodotto attraverso tecniche MAR, di illustrare i progressi compiuti nelle varie tipologie di MAR e di mettere questi in relazione con gli avanzamenti nella ricerca e nella regolamentazione. Di fronte al cambiamento del clima e all’aumento dell’intensità degli eventi climatici estremi, le tecniche MAR rappresentano una strategia di gestione delle acque sempre più importante, insieme alla gestione della domanda, per mantenere, migliorare e proteggere i sistemi acquiferi sotto pressione e per salvaguardare e migliorare la qualità delle acque. In questo arco di tempo, la ricerca scientifica relativa alla progettazione idraulica degli impianti, agli studi con traccianti, alla gestione dei fenomeni di intasamento, all’efficienza di recupero ed. alle modifiche della qualità delle acque sotterranee, ha supportato i miglioramenti pratici nei sistemi MAR e ha prodotto benefici in senso più ampio in idrogeologia. I pozzi di ricarica hanno largamente contribuito ad incrementare il ravvenamento degli acquiferi, in particolare nelle aree urbane e nella gestione delle acque di miniera. Negli ultimi anni sono state intraprese ricerche sulla governance, le pratiche operative, l’affidabilità, l’economicità, la valutazione del rischio e l’accettazione pubblica dei sistemi MAR. Dagli anni ‘60, la realizzazione di sistemi MAR è progredita ad un tasso del 5% all’anno, ma non sta tenendo il passo con l’aumento dei prelievi delle acque sotterranee. Attualmente si stima che i sistemi MAR forniscano circa 10 km3/anno, circa il 2.4% dei prelievi di acque sotterranee nei paesi che riportano la presenza di impianti MAR (o ~1.0% del prelievo globale di acque sotterranee). Si ritiene, sulla base dei dati provenienti dai paesi in cui l’uso di questa tecnica è avanzato, che i volumi immagazzinati attraverso i sistemi MAR potranno arrivare a superare il 10% dei prelievi globali, sostenendo la disponibilità, affidabilità e qualità delle risorse idriche.The last 60 years has seen unprecedented groundwater extraction and overdraft as well as development of new technologies for water treatment that together drive the advance in intentional groundwater replenishment known as managed aquifer recharge (MAR). This paper is the first known attempt to quantify the volume of MAR at global scale, and to illustrate the advancement of all the major types of MAR and relate these to research and regulatory advancements. Faced with changing climate and rising intensity of climate extremes, MAR is an increasingly important water management strategy, alongside demand management, to maintain, enhance and secure stressed groundwater systems and to protect and improve water quality. During this time, scientific research—on hydraulic design of facilities, tracer studies, managing clogging, recovery efficiency and water quality changes in aquifers—has underpinned practical improvements in MAR and has had broader benefits in hydrogeology. Recharge wells have greatly accelerated recharge, particularly in urban areas and for mine water management. In recent years, research into governance, operating practices, reliability, economics, risk assessment and public acceptance of MAR has been undertaken. Since the 1960s, implementation of MAR has accelerated at a rate of 5%/year, but is not keeping pace with increasing groundwater extraction. Currently, MAR has reached an estimated 10 km3/year, ~2.4% of groundwater extraction in countries reporting MAR (or ~1.0% of global groundwater extraction). MAR is likely to exceed 10% of global extraction, based on experience where MAR is more advanced, to sustain quantity, reliability and quality of water supplies
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