Publications by authors named "Vagner T"

Mammalian cells release a heterogeneous array of extracellular vesicles (EVs) that contribute to intercellular communication by means of the cargo that they carry. To resolve EV heterogeneity and determine if cargo is partitioned into select EV populations, we developed a method named "EV Fingerprinting" that discerns distinct vesicle populations using dimensional reduction of multiparametric data collected by quantitative single-EV flow cytometry. EV populations were found to be discernible by a combination of membrane order and EV size, both of which were obtained through multiparametric analysis of fluorescent features from the lipophilic dye Di-8-ANEPPS incorporated into the lipid bilayer.

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Optimizing outcomes in prostate cancer (PCa) requires precision in characterization of disease status. This effort was directed at developing a PCa extracellular vesicle (EV) Digital Scoring Assay (DSA) for detecting metastasis and monitoring progression of PCa. PCa EV DSA is comprised of an EV purification device (i.

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Nanomaterials are characterized by an extremely large surface-to-volume ratio. Extracellular Vesicles (EVs) - which have been recently recognized as the universal agent of intercellular communication, being involved in many physiological and pathological processes and interkingdom biochemical communication - are nanoparticles, but this key aspect has never been rationally addressed. Here we report the first attempt to quantify the membrane-to-lumen partition of proteins in EVs.

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Extracellular vesicles (EVs) are membrane-enclosed particles that play an important role in cancer progression and have emerged as a promising source of circulating biomarkers. Protein -acylation, frequently called palmitoylation, has been proposed as a post-translational mechanism that modulates the dynamics of EV biogenesis and protein cargo sorting. However, technical challenges have limited large-scale profiling of the whole palmitoyl-proteins of EVs.

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Tumor-derived extracellular vesicles (EVs) present in bodily fluids are emerging liquid biopsy markers for non-invasive cancer diagnosis and treatment monitoring. Because the majority of EVs in circulation are not of tumor origin, it is critical to develop new platforms capable of enriching tumor-derived EVs from the blood. Herein, we introduce a biostructure-inspired NanoVilli Chip, capable of highly efficient and reproducible immunoaffinity capture of tumor-derived EVs from blood plasma samples.

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Extracellular vesicles (EVs) are membrane-enclosed particles that are released by virtually all cells from all living organisms. EVs shuttle biologically active cargo including protein, RNA, and DNA between cells. When shed by cancer cells, they function as potent intercellular messangers with important functional consequences.

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Cancer-derived extracellular vesicles (EVs) are membrane-enclosed structures of highly variable size. EVs contain a myriad of substances (proteins, lipid, RNA, DNA) that provide a reservoir of circulating molecules, thus offering a good source of biomarkers. We demonstrate here that large EVs (L-EV) (large oncosomes) isolated from prostate cancer (PCa) cells and patient plasma are an EV population that is enriched in chromosomal DNA, including large fragments up to 2 million base pair long.

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Huntington's disease (HD) affects both neurons and astrocytes. To target the latter and to ensure brain-wide transgene expression, adeno-associated viral (AAV) vectors can be administered intravenously, as AAV vectors cross the blood-brain barrier (BBB) and enable preferential transduction of astrocytes due to their close association with blood vessels. However, there is a possibility that the subclass of GFAP-expressing astrocytes performs a distinct role in HD and reacts differently to therapeutic measures than the rest of the astrocytes.

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Unlabelled: This study evaluates single-cell indicators of glutamate transport in sulforhodamine 101-positive astrocytes of Q175 mice, a knock-in model of Huntington's disease (HD). Transport-related fluorescent ratio signals obtained with sodium-binding benzofuran isophtalate (SBFI) AM from unperturbed or voltage-clamped astrocytes and respective glutamate transporter currents (GTCs) were induced by photolytic or synaptic glutamate release and isolated pharmacologically. The HD-induced deficit ranged from -27% (GTC maximum at -100 mV in Ba(2+)) to -41% (sodium transients in astrocytes after loading SBFI-AM).

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Article Synopsis
  • Huntington's disease (HD) is a genetic neurodegenerative disorder characterized by motor symptoms, particularly the hypokinetic-rigid phenotype, which can be studied using the Q175 mouse model.
  • At one year old, Q175 mice showed significant reductions in spontaneous movements, increased inactivity, and delays in reactions, indicating severe hypokinesia, without notable loss of certain striatal neurons.
  • Findings suggest that decreased dopamine release and impaired cortico-striatal synaptic transmission contribute to hypokinesia in HD, evidenced by changes in synaptic activity and neurotransmitter signaling in the affected mice.
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Introduction: Apoptosis is involved in pathological cell death of a wide range of human diseases. One of the most important biochemical markers of apoptosis is activation of caspase-3. Ability to detect caspase-3 activation early in the pathological process is important for determining the timing for interfering with apoptosis initiation and prevention of cell damage.

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Unicellular, diazotrophic cyanobacteria temporally separate dinitrogen (N2) fixation and photosynthesis to prevent inactivation of the nitrogenase by oxygen. This temporal segregation is regulated by a circadian clock with oscillating activities of N2 fixation in the dark and photosynthesis in the light. On the population level, this separation is not always complete, since the two processes can overlap during transitions from dark to light.

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Huntington's disease (HD) is caused by a dominant mutation that results in an unstable expansion of a CAG repeat in the huntingtin gene leading to a toxic gain of function in huntingtin protein which causes massive neurodegeneration mainly in the striatum and clinical symptoms associated with the disease. Since the mutation has multiple effects in the cell and the precise mechanism of the disease remains to be elucidated, gene therapy approaches have been developed that intervene in different aspects of the condition. These approaches include increasing expression of growth factors, decreasing levels of mutant huntingtin, and restoring cell metabolism and transcriptional balance.

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We describe an open-source freeware programme for high throughput analysis of nanoSIMS (nanometre-scale secondary ion mass spectrometry) data. The programme implements basic data processing and analytical functions, including display and drift-corrected accumulation of scanned planes, interactive and semi-automated definition of regions of interest (ROIs), and export of the ROIs' elemental and isotopic composition in graphical and text-based formats. Additionally, the programme offers new functions that were custom-designed to address the needs of environmental microbiologists.

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Investigating the contribution of microbial populations to biochemical processes of global significance is challenging as there are few approaches that can detect microbial metabolic activities on single-cell level. Given the widespread distribution and importance of microorganisms in elemental transformations, improved methods for measuring microbial activities in naturally occurring microbial communities is essential. In this article, microautoradiography (MAR), Raman microspectroscopy, and Secondary Ion Mass Spectrometry (SIMS) and their combination with isotope labeling and molecular genetic methods for cell identification (i.

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Many diatoms that inhabit low-nutrient waters of the open ocean live in close association with cyanobacteria. Some of these associations are believed to be mutualistic, where N(2)-fixing cyanobacterial symbionts provide N for the diatoms. Rates of N(2) fixation by symbiotic cyanobacteria and the N transfer to their diatom partners were measured using a high-resolution nanometer scale secondary ion mass spectrometry approach in natural populations.

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Carbon and nitrogen fluxes in Aphanizomenon sp. colonies in the Baltic Sea were measured using a combination of microsensors, stable isotopes, mass spectrometry, and nanoscale secondary ion mass spectrometry (nanoSIMS). Cell numbers varied between 956 and 33 000 in colonies ranging in volume between 1.

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The study was aimed at defining the informative value of dynamic hepatobiliary scintigraphy (HBSG) in the evaluation of duodenal reflux in patients with postgastrectomic disorders after reconstructive surgery. HBSG was performed in 23 patients. After intravenous injection of 99mTc bromeside in a dose of 74-80 MBq, the areas concerned were identified in the projection of the liver, gallbladder, hepaticocholedochus, duodenum, and stomach for 120 minutes with 60-min cholagogic breakfast.

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The blood rheologic properties were studied in 49 patients with chronic arterial insufficiency. The values of systemic and regional circulation were studied in 25 patients. Changes in blood viscosity and aggregate condition were found to play an essential role in the occurrence of general and regional hemodynamic disorders.

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Examined were 47 patients with acute ischemia of the extremities: 29--with favourable outcome, and 18-with the development of gangrene. Scintigraphy of the extremity with 99mTc-Sn-pyrophosphate was performed; urinary excretion of epinephrine and norepinephrine, DOPA and dopamine, and vanillylmandelic acid as well was studied; the content of ACTH, cortisol and cyclic adenosine monophosphate in the blood was defined. The use of radionuclide and biochemical methods of investigation permits to assess the degree of severity of the ischemic injury to the tissues of the extremities.

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A comparative effectiveness of hemosorption in relation to atherosclerotic or autoimmune genesis of the disease is presented by results of the treatment of 41 patients with chronic arterial insufficiency of the extremities. The effectiveness of hemosorption is shown to be significantly higher in patients with autoimmune genesis of the disease than with atherosclerosis.

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