Plasma Light Research Articles

Validation of Plasma and CSF Neurofilament Light Chain as an Early Marker for Sporadic Creutzfeldt-Jakob Disease.

Biomarkers are becoming increasingly important for the differential diagnosis of neurodegenerative diseases. Previous observations indicated neurofilament light chain (NfL) as a potential blood-based biomarker for sporadic Creutzfeldt-Jakob disease (sCJD). Here, we investigated the stability, inter-assay/intra-assay variation and the regulation of NfL levels in CSF and plasma in a large cohort of sCJD patients by using a single-molecule array (SIMOA). We defined cutoffs for an accurate diagnosis and measured plasma NfL level in prion-infected mice models at different time points to identify the potential dynamics throughout the disease. Our analyses confirmed CSF and plasma NfL as stable and consistent marker for sCJD. Receiver operating characteristic (ROC) curve analysis showed an AUC of 0.92-0.93 to distinguish sCJD from control groups. Newly defined cutoffs revealed good diagnostic accuracies of CSF and plasma NfL, indicated by a sensitivity of 80-83.5% and a specificity of 87.4-91%. Studies on two humanized prion-infected mice lines (Tg340-PRNP129MM and Tg361-PRNP129VV) revealed increased plasma NfL levels in a late pre-clinical or very early clinical stage between 120-150days post-inoculation. In conclusion, our work supports the potential use of CSF and plasma NfL as a very early biomarker in sCJD diagnostic with good diagnostic accuracies.

Screening for neurodegeneration in Langerhans cell histiocytosis with neurofilament light in plasma.

SummaryPatients with Langerhans cell histiocytosis (LCH) may develop progressive neurodegeneration in the central nervous system (ND‐CNS‐LCH). Neurofilament light protein (NFL) in cerebrospinal fluid (CSF) is a promising biomarker to detect and monitor ND‐CNS‐LCH. We compared paired samples of NFL in plasma (p‐NFL) and CSF in 10 patients (19 samples). Nine samples had abnormal CSF‐NFL (defined as ≥380 ng/l) with corresponding p‐NFL ≥ 2 ng/l. Ten samples had CSF‐NFL < 380 ng/l; eight (80%) with p‐NFL < 2 ng/l (p < 0.001; Fisher's exact test). Thus, our results suggest that p‐NFL may be used to screen for ND‐CNS‐LCH. Further studies are encouraged, including the role of p‐NFL for monitoring of ND‐CNS‐LCH.

Interaction of powerful plasma jets with Mo/Si multilayers

The paper presents some results of experimental studies of Mo/Si multilayer degradation under UV exposure from compressed plasma jets in air. Such high current plasma flows generate broadband powerful UV radiation fluxes. A single exposure caused a slight decrease of reflectivity from 0.54 to 0.47 due to the coating contamination by the debris from the plasma light emitter.

Laboratory system for optical coherence tomography (OCT) using a laser plasma source of soft x-rays and extreme ultraviolet and focusing ellipsoidal optics.

Optical coherence tomography (OCT) with the use of soft x-rays (SXR) and extreme ultraviolet (EUV) has been recently demonstrated [Fuchs et al. Sci. Rep.6, 20658 (2016)10.1038/srep20658; Fuchs et al. Optica4, 903 (2017)10.1364/OPTICA.4.000903]. This new imaging technique, named XCT, makes it possible to obtain cross-sectional and tomographic images of objects with nanometer spatial resolution. The article presents a newly developed laboratory system for XCT using a compact laser plasma light source operating in the SXR and EUV spectral ranges. The source is based on a gas puff target containing Kr gas or a Kr/Xe gas mixture irradiated with nanosecond laser pulses from an Nd:YAG laser. The use of the gas puff target enables efficient emission of SXR and EUV radiation without generating target debris associated with laser ablation when using a solid target. The system is equipped with an ellipsoidal mirror to collect radiation from the source and focus on the imaged object. The XCT measurements are made by processing the spectrum of the radiation reflected from the object recorded with a transmission grating spectrometer equipped with an identical focusing mirror and a CCD camera. The paper presents the characterization and optimization of the new XCT system and its application to the measurements of layered nanostructures.

194 nm microplasma lamps driven by excitation transfer: optical sources for the 199Hg ion atomic clock and photochemistry

A series of miniature, microcavity plasma lamps emitting predominantly at 194 nm has been successfully developed and tested as the optical pump for the microwave 199Hg-ion atomic clock (40.507 GHz), replacing low pressure, RF-powered Ar/Hg discharges. Intense fluorescence on the 6p 2P1/2 → 6s 2S1/2 transition of the singly-charged 202Hg ion at 194.23 nm has been generated in arrays of cylindrical microplasmas through electron-impact excitation of He, followed by three-body formation of He2(a 3 ) and Penning ionization of Hg. Emission spectroscopy and kinetic modeling of He/Hg vapor plasmas demonstrate that the population of the Hg+(62P1/2) radiating state (16.82 eV), produced by direct or two-step electron impact processes, is 1% of that generated by excitation transfer to Hg by H. Flat, fused silica lamps having emitting areas as small as 4 mm2 and containing several mg of 202Hg and 50–800 Torr of He have been fabricated and serve as optical drivers for the Hg+ atomic clock cycle. Based on small arrays of 500 μm–1 mm diameter microcavities, these lamps produce peak and average intensities at 194 nm greater than those associated with the Hg resonance transition at ∼ 254 nm, despite the factor of 3 difference between the energies of the 6p 3P1 and 6p 2P1/2 states of neutral Hg and Hg+, respectively. These lamps are unique in the sense that the desired radiating species is an excited ion and the background He gas pressure can reach 1 atm, both of which contribute to a dense glow plasma placing severe demands on E/N, power conditioning, and materials selection. Nevertheless, with proper attention given to design, vacuum processing, and preparation of the lamps, lifetimes above 1500 h have been realized to date. When these lamps drive Jet Propulsion Laboratory Hg+ clocks, the stability floor has been measured to be −14. The implications of this lamp for gas-phase and solid-state photochemistry are also discussed.

Fundamental Concepts and Discussion of Plasma Physics

Plasma physics is the state of matter, which consists of charged particles. Plasma is usually produced by heating a gas so that the electrons are separated from the atom or molecule from which it is made. Upper ionization can be performed using high power laser or microwave lighting. Plasma occurs naturally in stars and space. In physics, a plasma is an electrical conductor that has the same number of positively and negatively charged particles. What happens when atoms of a gas are ionized. It is sometimes called the fourth state of matter. Unlike rigid bodies, liquids and gases, negative ions are often carried by electrons. Every work has a reverse side. Positive charges are usually carried by atoms or molecules that do not have identical electrons. In some rare but curious cases, the missing electrons of one type of atom or molecule bond with another. As a result, positive and negative ions are present in the plasma. The most severe cases of this type occur when the dust is low. But as dust particles, they are added in a state known as plasma dust. The peculiarity of the state of the plasma is due to the value of the electrical and magnetic energy acting on the plasma. Affects all types of matter, except for gravitational attraction. Because the electromagnetic force can work over long distances. Therefore, the plasma acts as a fluid group. Although the particles rarely collide. Almost all visible objects in the Universe are in the plasma state. Most of them are found in sunlight and stars in this form. And the space between planets and stars, auroras, lightning and arcades are also plasma. Available with both plasma and fluorescent lamps. In addition to the rigid crystalline structure of the metal, among many other phenomena and objects, the Earth itself is immersed in a thin plasma. Called the solar wind and surrounded by a dense plasma called the ionosphere.

Attachment and Osteogenic Potential of Dental Pulp Stem Cells on Non-Thermal Plasma and UV Light Treated Titanium, Zirconia and Modified PEEK Surfaces.

Ultraviolet (UV) light and non-thermal plasma (NTP) treatment are chairside methods that can efficiently improve the biological aging of implant material surfaces caused by customary storage. However, the behaviors of stem cells on these treated surfaces of the implant are still unclear. This study aimed to investigate the effects of UV light and NTP treated surfaces of titanium, zirconia and modified polyetheretherketone (PEEK, BioHPP) on the attachment and osteogenic potential of human dental pulp stem cells (DPSCs) in vitro. Machined disks were treated using UV light and argon or oxygen NTP for 12 min each. Untreated disks were set as controls. DPSCs were cultured from the wisdom teeth of adults that gave informed consent. After 24 h of incubation, the attachment and viability of cells on surfaces were assessed. Cells were further osteogenically induced, alkaline phosphatase (ALP) activity was detected via a p-Nitrophenyl phosphate assay (day 14 and 21) and mineralization degree was measured using a Calcium Assay kit (day 21). UV light and NTP treated titanium, zirconia and BioHPP surfaces improved the early attachment and viability of DPSCs. ALP activity and mineralization degree of osteoinductive DPSCs were significantly increased on UV light and NTP treated surfaces of titanium, zirconia and also oxygen plasma treated Bio-HPP (p < 0.05). In conclusion, UV light and NTP treatments may improve the attachment of DPSCs on titanium, zirconia and BioHPP surfaces. Osteogenic differentiation of DPSCs can be enhanced on UV light and NTP treated surfaces of titanium and zirconia, as well as on oxygen plasma treated Bio-HPP.

Consecutive treatments of cold plasma and intense pulsed light for microbial decontamination of fresh cabbage slices in plastic containers

Consecutive treatment with intense pulsed light (IPL) and cold plasma (CP) was evaluated as an intervention technology to decontaminate cabbage slices in plastic containers. Salmonella inactivation efficacy increased as the treatment time and voltage of IPL and CP treatments increased. The rotation of the container during IPL treatment as well as the selected sequence of treatment, CP treatment followed by IPL treatment (CP-IPL), were beneficial in inactivating Salmonella. Under the determined conditions (CP: 24.5 kV, 2 min; IPL: 1.5 kV, 2 min), the inactivation levels of Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, and Bacillus cereus spores using CP-IPL treatment were 3.1, 2.9, 3.2 log CFU/g, and 2.1 log spores/g, respectively. The efficacy of Salmonella inactivation in cabbage slices using CP-IPL treatment was maintained during storage at 4 °C and 10 °C. CP-IPL treatment did not alter the color and lipid peroxidation of cabbage slices. At identical treatment times, CP-IPL treatment alleviated the antioxidant activity decrease and the damage to the cabbage cell membrane compared with CP treatment alone, while resulting in a higher microbial inactivation efficacy. This study demonstrates that CP-IPL treatment has the potential to effectively increase the microbiological safety of cabbage slices in plastic containers with minimal impact on their quality.

Upgraded TV Thomson scattering system on the T-10 tokamak

The Thomson scattering system on the tokamak T-10 was upgraded in 2016. The new system is based on previous diagnostic with replacement of main components: laser, fiber bundle and camera. It is the first TS system combining Nd:YAG laser with a TV registration. Previous laser was replaced by a new 100 Hz Nd:YAG laser working during the whole plasma discharge on the second harmonic (λ = 532 nm) with pulse energy of 2,5 J and a duration of 10 ns. A multi-pass system with 5 passes of the beam through the plasma volume is used to inject laser light into the vacuum chamber. The scattered light is transported to the spectrometer by means of a new fiber-optic bundle providing a high spatial resolution of 5 mm over the full plasma diameter of 600 mm. An image intensifier with a GaAs photocathode and a P43 phosphor is used for detection. Fast CMOS camera Vision Research Phantom V7.3 captures images and allows to measure background plasma light between laser pulses. The diagnostic worked during three experimental campaigns and demonstrated the operability in various plasma regimes.

Investigation on property of electron beam plasma with diamond window

The properties of Ar plasma generated by electron beam with initial energy of 45 keV passing through a 5 μm-thick diamond film window was investigated by experimental diagnostic and Monte Carlo simulation. It is found that the plasma light emission intensity enhances with increasing the electron beam current, while the plasma shape has no significant change. When the gas pressure increases, the plasma shrinks and becomes brighter, and its shape gradually changes from cone-shape to semi prolate spheroid. The electron density increases with increasing gas pressure and electron current. When the gas pressure is higher than 10 kPa, the electron density can reach the order of 1010 cm−3 at an electron current of 0.3 mA. Under high-pressure conditions, the plasma range with respect to gas pressure satisfies well a simple inverse relationship. The electron energy deposition distribution obtained by Monte Carlo simulation is consistent with the measured plasma light emission intensity distribution. Optical emission spectroscopy was used to analyze collision process in the electron beam plasma. The line intensities of the 2p 2, 2p 6 and 2p 10 levels grow relatively with increasing gas pressure, indicating that the atom-atom collisional processes are enhanced.

Circulating LIGHT (TNFSF14) and Interleukin-18 Levels in Sepsis-Induced Multi-Organ Injuries.

The novel therapeutic target cytokine LIGHT (TNFSF14) was recently shown to play a major role in COVID-19-induced acute respiratory distress syndrome (ARDS). This study aims to investigate the associations of plasma LIGHT and another potentially targetable cytokine, interleukin-18 (IL-18), with ARDS, acute hypoxic respiratory failure (AHRF), or acute kidney injury (AKI), caused by non-COVID-19 viral or bacterial sepsis. A total of 280 subjects diagnosed with sepsis, including 91 cases with sepsis triggered by viral infections, were investigated in this cohort study. Day 0 plasma LIGHT and IL-18, as well as 59 other biomarkers (cytokines, chemokines, and acute-phase reactants) were measured by sensitive bead immunoassay and associated with symptom severity. We observed significantly increased LIGHT level in both bacterial sepsis patients (p = 1.80 × 10−5) and patients with sepsis from viral infections (p = 1.78 × 10−3). In bacterial sepsis, increased LIGHT level was associated with ARDS, AKI, and higher Apache III scores, findings also supported by correlations of LIGHT with other biomarkers of organ failure. IL-18 levels were highly variable across individuals and consistently correlated with Apache III scores, mortality, and AKI in both bacterial and viral sepsis. There was no correlation between LIGHT and IL-18. For the first time, we demonstrate independent effects of LIGHT and IL-18 in septic organ failure. The association of plasma LIGHT with AHRF suggests that targeting the pathway warrants exploration, and ongoing trials may soon elucidate whether this is beneficial. Given the large variance of plasma IL-18 among septic subjects, targeting this pathway requires precise application.

Osseointegration of Zirconia Implants after UV-Light or Cold Atmospheric Plasma Surface Treatment In Vivo.

The influence of UV light and non-thermal plasma on the osseointegration of yttria-stabilized zirconia implants (Y-TZP) comparing the two methods is unclear. The aim of this study was to show the influence of these methods on the osseointegration of dental zirconia implants in an animal model. A total of 54 implants were either untreated, treated with UV light (UV), or non-thermal oxygen plasma for 12 min and inserted into the parietal bones of six domestic pigs. The animals were sacrificed after a healing interval of two, four, and nine weeks. The degree of osseointegration was determined using histomorphometric determination of bone-to-implant contact values (BIC) and the bone-to-implant contact values within the retentive parts of the implants (BAFO). BIC values decreased in all groups after four weeks of healing and re-increased after nine weeks in all groups. BAFO increased significantly over time in all groups. However, there were no statistically significant differences in BIC and BAFO values between the control group and the test groups and over time. Clinical studies may follow to confirm the influence of cold plasma and UV light on the healing and survival of zirconia implants.

Hyperspectral infrared imaging of surface phonon-polaritons in SrTiO3

Polaritons have a demonstrated impact on nanophotonic applications in the midinfrared through visible spectral range. Surface phonon-polaritons (SPhPs) offer a way to bring the potential of polaritons to the longer infrared wavelengths. Strontium titanate (STO) is a perovskite polar dielectric with diverse technologically advantageous properties and it can support SPhPs in a uniquely broad spectral range of the far infrared. Despite these advantages, STO has mostly been overlooked as a nanophotonic material. In this work we investigate SPhP propagation in STO in the far-infrared through midinfrared spectral range using broadband, near-field nanospectroscopy. We developed a tabletop, laser sustained plasma light source that enabled us to obtain amplitude and phase resolved hyperspectral line scan maps of SPhPs across the surface of the STO sample. Analytical modeling of experimental data reveals the dispersion characteristics of SPhPs in STO. This work establishes STO as a platform for perovskite-based broadband far-infrared and terahertz nanophotonics.

High-Pressure Processing for Sustainable Food Supply

Sustainable food supply has gained considerable consumer concern due to the high percentage of spoilage microorganisms. Food industries need to expand advanced technologies that can maintain the nutritive content of foods, enhance the bio-availability of bioactive compounds, provide environmental and economic sustainability, and fulfill consumers’ requirements of sensory characteristics. Heat treatment negatively affects food samples’ nutritional and sensory properties as bioactives are sensitive to high-temperature processing. The need arises for non-thermal processes to reduce food losses, and sustainable developments in preservation, nutritional security, and food safety are crucial parameters for the upcoming era. Non-thermal processes have been successfully approved because they increase food quality, reduce water utilization, decrease emissions, improve energy efficiency, assure clean labeling, and utilize by-products from waste food. These processes include pulsed electric field (PEF), sonication, high-pressure processing (HPP), cold plasma, and pulsed light. This review describes the use of HPP in various processes for sustainable food processing. The influence of this technique on microbial, physicochemical, and nutritional properties of foods for sustainable food supply is discussed. This approach also emphasizes the limitations of this emerging technique. HPP has been successfully analyzed to meet the global requirements. A limited global food source must have a balanced approach to the raw content, water, energy, and nutrient content. HPP showed positive results in reducing microbial spoilage and, at the same time, retains the nutritional value. HPP technology meets the essential requirements for sustainable and clean labeled food production. It requires limited resources to produce nutritionally suitable foods for consumers’ health.

Reducing reflectivity of stimulated Raman scattering by discretely changing phase of incident light in inertial fusion plasmas

A new method to reduce the stimulated Raman scattering (SRS) in inertial confinement fusion conditions is proposed by changing the incident light phase discretely. The proposal is first examined by three-wave coupling equations and then verified by Vlasov simulations. A remarkable decreasing in SRS reflectivity is observed when the period of phase changing is less than where is the growth rate of SRS. By contrast, some simulations with continuously changing phase of incident light are carried out to compare their influence on SRS. In addition, the proposal may suppress the stimulated Brillouin scattering.

Plasma NfL trajectory during ICU‐treatment of COVID‐19 patients: A prospective cohort study

BackgroundCOVID‐19 is a respiratory disease where neurological sequelae are frequently reported. Neurofilament light (NfL) in plasma is a validated biomarker for neuronal damage. We assessed the trajectory of NfL levels in intensive care unit (ICU) patients diagnosed with COVID‐19, and studied its relationship to clinical outcomes and markers of hypothesized pathophysiological mechanisms.MethodAs part of the Art‐Deco study and Amsterdam UMC COVID‐biobank, longitudinal samples and clinical data were collected weekly from a cohort of 31 prospectively admitted ICU patients with a minimum of 7 days of ventilation. The mean±sd age was 63±11 years. Admission duration ranged from 14‐35 days and 156 samples were collected. We evaluated the NfL trajectory over time, and whether this trajectory differed by 90‐day mortality outcome. Due to the non‐linear trajectory of NfL, we applied linear mixed models including cubic splines for the time variable. Secondly, we tested whether baseline or peak NfL levels predicted mortality (n=7/31), delirium incidence after detubation (n=18/22), and duration of delirium (6±6 days). Third, we assessed if disease severity (day 7 Sequential Organ Failure Assessment [SOFA] score) and baseline hypoxemia (pAO2 before intubation), inflammation (IL1‐b, IL‐6, IL‐8, TNF‐α), and coagulopathy (d‐dimer, presence of pulmonary embolism) were predictive of the NfL trajectory. For the latter models, we included an interaction term for the pathophysiological markers in the linear mixed models. All models were adjusted for age.ResultNfL increased during ICU admission (p<001), and persisted longer in the non‐survivors (p<0.05;Figure 1). Baseline or maximum NfL was not predictive of mortality or delirium incidence. However, maximum NfL correlated to the duration of delirium (r=0.5;p=0.02). From the pathophysiological markers, SOFA scores (p<0.05) and baseline TNF‐α (p<0.05) were related to a stronger increase of NfL over time.ConclusionNfL levels increased over time and plateaued after 2‐3 weeks in most COVID‐19 patients at the ICU. Peak levels of NfL were predictive of delirium persistence. Repeated NfL levels may provide a future method for monitoring neurological outcomes in sedated ICU patients. Disease severity and specific inflammatory components appear important predictors of the NfL trajectory reflecting axonal damage in severe COVID‐19 patients.

Plasma and cerebrospinal fluid neurofilament light protein concentrations are differentially associated with biomarker evidence of neurodegeneration in a community‐based population of 70‐year‐olds

AbstractBackgroundNeurofilament light protein (NfL) is the best‐established fluid biomarker for general neurodegeneration, predicting poor outcome in cognitive function across neurodegenerative dementias. Currently, there are few studies examining the correlation of plasma and cerebrospinal fluid (CSF) NfL with other fluid and imaging biomarkers for neurodegeneration.MethodThe sample (n= 287) was derived from the Gothenburg H70 Birth cohort 1944 study, conducted in 2014‐2016. CSF NfL, total‐Tau (t‐Tau), phospho‐Tau (p‐Tau), neurogranin, CSF/serum albumin ratio and plasma NfL were measured and brain magnetic resonance imaging (MRI) was conducted. Participants were examined with comprehensive neuropsychiatric and somatic examinations, and dementia was diagnosed according to DSM III criteria. In linear models adjusted for age and sex, NfL was examined in relation to other demographics, cognitive tests, CSF biomarkers and MRI measurements. Sub analysis were also performed on participants with or without β‐Amyloid pathology, defined as a CSF β‐Amyloid 42 ≤ 530 pg/mL.ResultNfL in plasma and CSF presented a moderate correlation (Spearman’s R=0.41, p&lt;0.001). P‐NfL was associated with worse delayed memory recall (p=0.019), smaller hippocampus volume (p=0.001), larger white matter lesion volume (p=0.004), as well as CSF levels of β‐amyloid 42 (p=0.043), β‐amyloid 42/40 (p=0.049), β‐amyloid 42/t‐Tau (p=0.007), CSF NfL (p&lt;0.001) and BMI (p&lt;0.001). CSF NfL was associated with t‐Tau (p=0.001), p‐Tau (p&lt;0.001), neurogranin (p=0.014), albumin ratio (Qalb) (p=0.001), P‐NfL (p&lt;0.001), and BMI (p=0.033). In participants with prevalent β‐amyloid 42 pathology, P‐NfL was associated with β‐amyloid 42 (p=0.009), β‐amyloid 42/40 (p=0.043), β‐amyloid 42/t‐Tau (p=0.010) and CSF NfL (p&lt;0.001). In participants without β‐amyloid 42 pathology, P‐NfL associated with BMI (p&lt;0.001), smaller hippocampus volume (p=0.007) and CSF NfL (p&lt;0.001).ConclusionAlthough CSF NfL and P‐NfL concentrations are correlated, the biomarker measured in the two sample types presents distinct associations with biomarker evidence of AD pathology and neurodegeneration. P‐NfL was associated with several markers that are characteristic of AD, whereas CSF NfL demonstrated more associations with synaptic and neurodegeneration.

Neurofilament light in plasma is a potential biomarker of central nervous system involvement in systemic lupus erythematosus.

Neuropsychiatric manifestations (NP) are common in systemic lupus erythematosus (SLE). However, the pathophysiological mechanisms are not completely understood. Neurofilament light protein (NfL) is part of the neuronal cytoskeleton. Increased NfL concentrations, reflecting neurodegeneration, is observed in cerebrospinal fluid (CSF) in several neurodegenerative and neuroinflammatory conditions. We aimed to explore if plasma NfL could serve as a biomarker for central nervous system (CNS) involvement in SLE. Sixty-seven patients with SLE underwent neurological examination; 52 underwent lumbar puncture, while 62 underwent cerebral magnetic resonance imaging (MRI). We measured selected auto-antibodies and other laboratory variables postulated to have roles in NP pathophysiology in the blood and/or CSF. We used SPM12 software for MRI voxel-based morphometry. Age-adjusted linear regression analyses revealed increased plasma NfL concentrations with increasing creatinine (β = 0.01, p < 0.001) and Q-albumin (β = 0.07, p = 0.008). We observed higher plasma NfL concentrations in patients with a history of seizures (β = 0.57, p = 0.014), impaired motor function (β = 0.36, p = 0.008), increasing disease activity (β = 0.04, p = 0.008), and organ damage (β = 0.10, p = 0.002). Voxel-based morphometry suggested an association between increasing plasma NfL concentrations and the loss of cerebral white matter in the corpus callosum and hippocampal gray matter. Increased plasma NfL concentrations were associated with some abnormal neurological, cognitive, and neuroimaging findings. However, plasma NfL was also influenced by other factors, such as damage accrual, creatinine, and Q-albumin, thereby obscuring the interpretation of how plasma NfL reflects CNS involvement. Taken together, NfL in CSF seems a better marker of neuronal injury than plasma NfL in patients with SLE.

Relativistic Self-Trapping of Extreme Laser Light in an Inhomogeneous Plasma

Relativistic Self-Trapping of Extreme Laser Light in an Inhomogeneous Plasma

Neurofilament Light in CSF and Plasma Is a Marker of Neuronal Damage in HTLV-1-Associated Myelopathy and Correlates With Neuroinflammation.

Background and ObjectivesTo evaluate the usefulness of CSF and plasma neurofilament light (Nf-L) as a biomarker for human T-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy (HAM).MethodsNf-L, CXCL10, and neopterin were measured by ELISA in 83 CSF samples obtained from 49 individuals living with HTLV-1/2. Plasma Nf-L was also measured by single molecule array. Results were correlated with duration of disease, age, mobility, CSF cell counts, CSF protein, and HTLV-1 proviral load.ResultsNf-L was detected in all CSF samples (median [range] = 575 [791.8–2,349] pg/mL) and positively correlated with markers of inflammation (CXCL10 (r = 0.733), neopterin (r = 0.499), cell count (r = 0.403), and protein levels (r = 0.693) in CSF; p < 0.0015). There was an inverse correlation between Nf-L and duration of disease (r = −0.584, p < 0.0001). Wheelchair-dependent patients had high concentrations of markers of inflammation and neuronal damage. Concentrations of CXCL10, neopterin, and Nf-L remained elevated in follow-up samples (mean follow-up 5.2 years). Nf-L in plasma correlated with concentration of Nf-L, neopterin, CXCL10, and protein in CSF.ConclusionsNf-L in plasma and CSF has potential to be used as a biomarker of disease activity in HAM. Neuronal damage seems to be more intense early in disease but persists long term. Wheelchair-dependent patients have ongoing neuroinflammation.