337 research outputs found

    The early dendritic cell signaling induced by virulent Francisella tularensis strain occurs in phases and involves the activation of ERKs and p38 in the later stage

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    Dendritic cells (DCs) infected by Francisella tularensis are poorly activated and do not undergo classical maturation process. While reasons of such unresponsiveness are not fully understood, their impact on the priming of immunity is well appreciated. Previous attempts to explain the behavior of Francisella-infected DCs were hypothesis-driven and focused on events at later stages of infection. Here, we took an alternative unbiased approach by applying methods of global phosphoproteomics to analyze the dynamics of cell signaling in primary DCs during the first hour of infection by Francisella tularensis. Presented results show that the early response of DCs to Francisella occurs in phases and that ERK and p38 signaling modules induced at the later stage are differentially regulated by virulent and attenuated ΔdsbA strain. These findings imply that the temporal orchestration of host pro-inflammatory pathways represents the integral part of Francisella life-cycle inside hijacked DCs

    Elektrokemijsko određivanje metalotioneina kod domaće peradi

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    Metallothionein (MT) belongs to group of intracellular, low-molecular and cysteine-rich proteins with a molecular weight from 6 to 10 kDa. Owing to their high affinity to heavy metals (Zn, Cd, As, etc.) their main role is homeostatic control and detoxification of metal ions in an organism. In the present work we aimed at suggesting and utilizing electroanalytical techniques to determine content of MT in the blood serum of domestic fowls. Electrochemical measurements were performed with an AUTOLAB Analyser connected to VA-Stand 663, using a standard cell with three electrodes. Particularly, MT was detected by adsorptive transfer stripping technique in connection with differential pulse voltammetry. The detection limit of MT was estimated down to 100 fM (standards only) or down to 100 pM measured in the presence of blood serum. The average content of MT was 21.3 µM. The MT level in hens was about 25 % higher than in cocks. This phenomenon can be related to higher demands on the content of this protein in hens due the requirement for ion transport to form eggshell.Metalotionein (MT) pripada grupi intracelularnih proteina male molekularne mase bogatih cisteinom, s molekularnom masom od 6 do 10 kDa. Zbog njihovog afiniteta prema teškim metalima (Zn, Cd, As, itd.) njihova glavna uloga je homeostatska kontrola i detoksifikacija iona metala u organizmu. U ovom radu predlažu se elektroanalitičke tehnike za određivanje sadržaja MT u krvnom serumu domaće peradi. Elektrokemijska mjerenja izvršena su uređajem AUTOLAB Analyser povezanim s VA-Stand 663, koristeći standardnu ćeliju s tri elektrode. Osim toga MT je određivan tehnikom adsorptivnog transfera, povezanoj s voltmetrijom diferencijalnog pulsa. Granica detekcije MT je procjenjivana do 100 fM (samo standardi) ili do 100 pM, mjereno u prisutnosti krvnog seruma. Prosječni sadržaj MT bio je 21.3 µM. Razina MT kod kokoši bila je otprilike 25% viša nego kod pijetlova. Ta pojava može se objasniti većom potrebom za ovim proteinom kod kokoši zbog transporta iona prilikom stvaranja ljuske jajeta

    A Machine Learning Approach to Support Treatment Identification for Chiari I Malformation

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    Chiari I malformation is characterized by the herniation of cerebellar tonsils below the foramen magnum. It is often accompanied by syringomyelia and neurosurgical management is still controversial. In fact, it is frequent that some symptomatic patients initially undergo bony decompression of the posterior fossa and need in a short time more invasive surgery with higher morbility (e.g., decompression of posterior fossa with dural plastic, with or without tonsillar coarctation) because of unsatisfactory results at MRI controls. This study proposes a machine learning approach (based on SVM classifier), applied to different morphometric indices estimated from sagittal MRI and some information on the patient (i.e., age and symptoms at diagnosis), to recognize patients with higher risk of syringomyelia and clinical deterioration. Our database includes 58 pediatric patients who underwent surgery treatment. A negative outcome at 1 year from the intervention was observed in 38% of them (accuracy of 62%). Our algorithm allows us to increase the accuracy to about 71%, showing it to be a valid support to neurosurgeons in refining the clinical picture

    An Adsorptive Transfer Technique Coupled with Brdicka Reaction to Reveal the Importance of Metallothionein in Chemotherapy with Platinum Based Cytostatics

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    The drugs based on platinum metals represent one of the oldest, but also one of the most effective groups of chemotherapeutic agents. Thanks to many clinical studies it is known that resistance of tumor cells to drugs is a frequent cause of chemotherapy failure. With regard to platinum based drugs, multidrug resistance can also be connected with increased expression of low-molecular weight protein metallothionein (MT). This study aimed at investigating the interactions of MT with cisplatin or carboplatin, using the adsorptive transfer technique coupled with differential pulse voltammetry Brdicka reaction (AdTS DPV Brdicka reaction), and a comparison of in vitro results with results obtained in vivo. The results obtained from the in vitro study show a strong affinity between platinum based drugs and MT. Further, we analyzed extracts of neuroblastoma cell lines treated with cisplatin or carboplatin. It is clear that neuroblastoma UKF-NB-4 cisplatin-resistant and cisplatin-sensitive cell lines unlikely respond to the presence of the platinum-based cytostatics cisplatin and carboplatin. Finally, we determined the level of MT in samples from rabbits treated with carboplatin and patients with retinoblastoma treated with the same drug

    Altered ceramide metabolism is a feature in the extracellular vesicle-mediated spread of alpha-synuclein in Lewy body disorders

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    This study was funded by the Lewy Body Society and the Michael J. Fox Foundation for Parkinson’s Research. A.H. and B.M.B. gratefully acknowledge funding from the Knut och Alice Wallenberg Stiftelse through the Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Sweden. S.T., M.K.D. and P.D.W. gratefully acknowledge the financial support of the European Regional Development Fund, Scottish Funding Council and Highlands and Islands Enterprise. Newcastle University TEM Services acknowledge BBSRC support (Grant code BB/R013942/1). The Research was supported by the National Institute for Health Research Newcastle Biomedical Research Centre based at Newcastle Hospitals NHS Foundation Trust and Newcastle University. The Newcastle Brain Tissue Resource is supported by grants from the UK Medical Research Council and the Brains for Dementia Research, a joint venture between Alzheimer’s Society and Alzheimer’s Research UK.Mutations in glucocerebrosidase (GBA) are the most prevalent genetic risk factor for Lewy body disorders (LBD)—collectively Parkinson’s disease, Parkinson’s disease dementia and dementia with Lewy bodies. Despite this genetic association, it remains unclear how GBA mutations increase susceptibility to develop LBD. We investigated relationships between LBD-specific glucocerebrosidase deficits, GBA-related pathways, and α-synuclein levels in brain tissue from LBD and controls, with and without GBA mutations. We show that LBD is characterised by altered sphingolipid metabolism with prominent elevation of ceramide species, regardless of GBA mutations. Since extracellular vesicles (EV) could be involved in LBD pathogenesis by spreading disease-linked lipids and proteins, we investigated EV derived from post-mortem cerebrospinal fluid (CSF) and brain tissue from GBA mutation carriers and non-carriers. EV purified from LBD CSF and frontal cortex were heavily loaded with ceramides and neurodegeneration-linked proteins including alpha-synuclein and tau. Our in vitro studies demonstrate that LBD EV constitute a “pathological package” capable of inducing aggregation of wild-type alpha-synuclein, mediated through a combination of alpha-synuclein–ceramide interaction and the presence of pathological forms of alpha-synuclein. Together, our findings indicate that abnormalities in ceramide metabolism are a feature of LBD, constituting a promising source of biomarkers, and that GBA mutations likely accelerate the pathological process occurring in sporadic LBD through endolysosomal deficiency.Publisher PDFPeer reviewe

    Effect of Cadmium Chloride on Metallothionein Levels in Carp

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    Due to anthropogenic activities, heavy metals still represent a threat for various trophic levels. If aquatic animals are exposed to heavy metals, we can obviously observe considerable toxicity. It is well known that organisms treated with heavy metals synthesize low molecular mass compounds rich in cysteine. In this work the effects of cadmium chloride (2.5, 5, 7.5, 10 and 12.5 mg/L) on common carp (Cyprinus carpio) was investigated. We determined cadmium content in tissue of muscle, liver and kidney by atomic absorption spectrometry with electrothermal atomization and content of metallothionein (MT) in the same tissues by the Brdicka reaction. Electrochemical methods can be considered as suitable and sensitive tools for MT determination in carp tissues. Results of our study showed a gradually enhancing of cadmium content in muscle with time and dose of cadmium chloride in water. MT levels in liver reached both high levels (above 130 ng/g) in fish exposed to 2.5, 5 and 7.5 mg/L and low level (to 50 ng/g) in fish exposed to 10 and 12.5 mg/L of cadmium chloride. This finding confirms that the synthesis of metallothioneins and binding capacity of these proteins is restricted

    Bio-Sensing of Cadmium(II) Ions Using Staphylococcus aureus†

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    Cadmium, as a hazardous pollutant commonly present in the living environment, represents an important risk to human health due to its undesirable effects (oxidative stress, changes in activities of many enzymes, interactions with biomolecules including DNA and RNA) and consequent potential risk, making its detection very important. New and unique technological and biotechnological approaches for solving this problems are intensely sought. In this study, we used the commonly occurring potential pathogenic microorganism Staphylococcus aureus for the determination of markers which could be used for sensing of cadmium(II) ions. We were focused on monitoring the effects of different cadmium(II) ion concentrations (0, 1.25, 2.5, 5, 10, 15, 25 and 50 μg mL−1) on the growth and energetic metabolism of Staphylococcus aureus. Highly significant changes have been detected in the metabolism of thiol compounds—specifically the protein metallothionein (0.79–26.82 mmol/mg of protein), the enzyme glutathione S-transferase (190–5,827 μmol/min/mg of protein), and sulfhydryl groups (9.6–274.3 μmol cysteine/mg of protein). The ratio of reduced and oxidized glutathione indicated marked oxidative stress. In addition, dramatic changes in urease activity, which is connected with resistance of bacteria, were determined. Further, the effects of cadmium(II) ions on the metabolic pathways of arginine, β-glucosidase, phosphatase, N-acetyl β-d-glucosamine, sucrose, trehalose, mannitol, maltose, lactose, fructose and total proteins were demonstrated. A metabolomic profile of Staphylococcus aureus under cadmium(II) ion treatment conditions was completed seeking data about the possibility of cadmium(II) ion accumulation in cells. The results demonstrate potential in the application of microorganisms as modern biosensor systems based on biological components

    Bio-Sensing of Cadmium(II) Ions Using Staphylococcus aureus†

    Get PDF
    Cadmium, as a hazardous pollutant commonly present in the living environment, represents an important risk to human health due to its undesirable effects (oxidative stress, changes in activities of many enzymes, interactions with biomolecules including DNA and RNA) and consequent potential risk, making its detection very important. New and unique technological and biotechnological approaches for solving this problems are intensely sought. In this study, we used the commonly occurring potential pathogenic microorganism Staphylococcus aureus for the determination of markers which could be used for sensing of cadmium(II) ions. We were focused on monitoring the effects of different cadmium(II) ion concentrations (0, 1.25, 2.5, 5, 10, 15, 25 and 50 μg mL−1) on the growth and energetic metabolism of Staphylococcus aureus. Highly significant changes have been detected in the metabolism of thiol compounds—specifically the protein metallothionein (0.79–26.82 mmol/mg of protein), the enzyme glutathione S-transferase (190–5,827 μmol/min/mg of protein), and sulfhydryl groups (9.6–274.3 μmol cysteine/mg of protein). The ratio of reduced and oxidized glutathione indicated marked oxidative stress. In addition, dramatic changes in urease activity, which is connected with resistance of bacteria, were determined. Further, the effects of cadmium(II) ions on the metabolic pathways of arginine, β-glucosidase, phosphatase, N-acetyl β-d-glucosamine, sucrose, trehalose, mannitol, maltose, lactose, fructose and total proteins were demonstrated. A metabolomic profile of Staphylococcus aureus under cadmium(II) ion treatment conditions was completed seeking data about the possibility of cadmium(II) ion accumulation in cells. The results demonstrate potential in the application of microorganisms as modern biosensor systems based on biological components

    Zeptomole Electrochemical Detection of Metallothioneins

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    Thiol-rich peptides and proteins possess a large number of biological activities and may serve as markers for numerous health problems including cancer. Metallothionein (MT), a small molecular mass protein rich in cysteine, may be considered as one of the promising tumour markers. The aim of this paper was to employ chronopotentiometric stripping analysis (CPSA) for highly sensitive detection of MT.In this study, we used adsorptive transfer stripping technique coupled with CPSA for detection of cysteine, glutathione oxidized and reduced, phytochelatin, bovine serum albumin, and metallothionein. Under the optimal conditions, we were able to estimate detection limits down to tens of fg per ml. Further, this method was applied to detect metallothioneins in blood serum obtained from patients with breast cancer and in neuroblastoma cells resistant and sensitive to cisplatin in order to show the possible role of metallothioneins in carcinogenesis. It was found that MT level in blood serum was almost twice higher as compared to the level determined in healthy individuals.This paper brings unique results on the application of ultra-sensitive electroanalytical method for metallothionein detection. The detection limit and other analytical parameters are the best among the parameters of other techniques. In spite of the fact that the paper is mainly focused on metallothionein, it is worth mentioning that successful detection of other biologically important molecules is possible by this method. Coupling of this method with simple isolation methods such as antibody-modified paramagnetic particles may be implemented to lab-on-chip instrument
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