31 research outputs found
Astrocytic S100B, Blood-Brain Barrier and Neurodegenerative Diseases
Increased life span and expectations of a better quality of life have resulted in a spotlight on neurodegenerative and cardiovascular diseases generally associated with aging. The drive toward evidence-based medicine has necessitated a constant search for objective biomarkers to assay disease onset, progress, and outcomes to make the best clinical decisions. Enhancement of their use depends on the mechanistic understanding of the biomarkerâs role in the disease process itself. This chapter focuses on S100B. It is a calcium sensor protein that is primarily astrocytic. While it plays a complex, interlinked role in signaling, serum levels of S100B as a biomarker for clinical decisions is also an area of intense investigation. Both aspects are presented, with an emphasis on the role of S100B in in maintaining a blood-brain barrier, especially in the context of suggesting a unified mechanism for the onset and progression of neurodegenerative diseases
Cytotoxic and apoptotic potential of Myristica fragrans Houtt. (mace) extract on human oral epidermal carcinoma KB cell lines
Several studies have revealed that certain naturally occurring medicinal plants inhibit the growth of various cancers. The present study was conducted to evaluate cytotoxicity and apoptotic induction potential of Myristica fragrans Houtt mace extract. The cytotoxic activity of the Myristica fragrans Houtt mace acetone extract was assayed by MTT assay on human oral epidermal carcinoma KB cell lines. KB cells were incubated with different concentration of mace extract ranging from 25 to 125ÎŒg/mL for 24hrs. The apoptotic induction potential was also studied by the analysis of Bcl-2 protein and gene expression in mace extract incubated KB cell lines using western blotting technique and real-time polymerase chain reaction. The mace extract exhibited cytotoxicity and anticancer effect against KB cell lines and it also suppressed the growth of cancer cells, therefore growth inhibitory effect was noted in extract treated cell lines. The apoptotic potential of mace extract was accompanied by reduced gene expression of Bcl-2 compared to the untreated KB cells. The mace extract shows the cytotoxic activity and induced the apoptosis through the modulation of its target genes Bcl-2 in the KB cell lines, suggesting the potential of mace as a candidate for oral cancer chemoprevention. This can be further investigated in vivo for its anticancer potential
Data on Final Calcium Concentration in Native Gel Reagents Determined Accurately Through Inductively Coupled Plasma Measurements
In this article we present data on the concentration of calcium as determined by Inductively Coupled Plasma (ICP) measurements. Calcium was estimated in the reagents used for native gel electrophoresis of Neuronal Calcium Sensor (NCS) proteins. NCS proteins exhibit calcium-dependent mobility shift in native gels. The sensitivity of this shift to calcium necessitated a precise determination of calcium concentrations in all reagents used. We determined the calcium concentrations in different components used along with the samples in the native gel experiments. These were: 20 mM Tris pH 7.5, loading dye and running buffer, with distilled water as reference. Calcium determinations were through ICP measurements. It was found that the running buffer contained calcium (244 nM) over the blank
Extravasated Brain-Reactive Autoantibodies Perturb Neuronal Surface Protein Expression in Alzheimer\u27s Pathology
Background: Increased blood-brain barrier (BBB) permeability is reported in both the neuropathological and in vivo studies in both Alzheimerâs Disease (AD) and age matched cognitively normal, no cognitive impairment (NCI), subjects. Impaired BBB allows various vascular components such as immunoglobulin G (IgG) to extravasate into the brain and specifically bind to various neuronal surface proteins (NSP), also known as brain reactive autoantibodies (BrABs). This interaction is predicted to further enhance deposition of amyloid plaques.
Hypothesis: Interaction between extravasated BrABs and its cognate NSPs lower the expression of that NSPs in AD patients.
Methods: We selected Western blotting technique to study the expression of various brain proteins and test our hypothesis. Fresh frozen brain samples of AD and NCI subjects were acquired, and total brain protein was extracted using protocol established in Acharya lab. We also identified various NSPs to study the impact of BrABs-NSPs interactions. Additionally, we investigated the expression of amyloid plaques ((amyloid precursor protein (APP)) and apoptosis (Caspase-3) markers. Specific NSPs examined included the alpha7 nicotinic acetylcholine receptor (α7nAChR) and anti-choline acetyltransferase (ChAT). To image the membranes, fluorescent imaging was used initially, which was later switched to chemiluminescence, after much troubleshooting.
Results: Most of the work done through these experiments was focused on establishing a thorough Western blot protocol that can be used to reliably perform these experiments. This involved determining the appropriate primary and secondary antibodies concentrations, loading concentrations, and testing different imaging settings to determine the most ideal image-acquisition conditions. Towards the end of the fellowship, we were successful in developing a protocol to further explore our investigation. Using this protocol, we were able to visualize bands for ChAT, α7nAChR, and caspase â 3.
Conclusions: Using this protocol further Western blot experiments can be run to study and compare the expression levels of various NSP in AD and control samples for testing our hypothesi
Near-Field Acousto Monitoring Shear Interactions Inside a Drop of Fluid: The Role of the Zero-Slip condition
A full understanding of nanometer-range (near-field) interactions between two sliding solid boundaries, with a mesoscopic fluid layer sandwiched in between, remains challenging. In particular, the origin of the blue-shift resonance frequency experienced by a laterally oscillating probe when approaching a substrate is still a matter of controversy. A simpler problem is addressed here, where a laterally oscillating solid probe interacts with a more sizable drop of fluid that rests on a substrate, aiming at identifying interaction mechanisms that could also be present in the near-field interaction case. It is found that the inelastic component of the probe-fluid interaction does not constitute the main energy-dissipation channel and has a weak dependence on fluidâs viscosity, which is attributed to the zero-slip hydrodynamic condition. In contrast, the acoustic signal engendered by the fluid has a stronger dependence on the fluidâs viscosity(attributed also to the zero-slip hydrodynamic condition) and correlates well with the probeâs resonancefrequency red-shift. We propose a similar mechanism happens in near field experiments, but a blue-shift in the probeâs resonance results as a consequence of the fluid molecules (subjected to the zero-slip condition at both the probe and substrate boundaries) exerting instead a spring type restoring force on the probe
Systemic Inflammation and Microbial Translocation Are Characteristic Features of SARS-CoV-2-Related Multisystem Inflammatory Syndrome in Children
BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) is a rare manifestation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children that can result in increased morbidity and mortality. The inflammatory underpinnings of MIS-C have not been examined in detail. METHODS: We examined the plasma levels of acute phase proteins and microbial translocation markers in children with MIS-C, children with acute coronavirus disease 2019 (COVID-19) infection, SARS-CoV-2-seropositive children, and controls. RESULTS: MIS-C children exhibited significantly higher levels of C-reactive protein (CRP), alpha2 macroglobulin (α2M), serum amyloid P (SAP), lipopolysaccharide (LPS), sCD14, and LPS binding protein (LBP) and significantly lower levels of haptoglobin (Hp) in comparison with seropositive, control, and/or COVID-19 children. In addition, COVID-19 children exhibited significantly higher levels of most of the above markers in comparison with seropositive and control children. Principal component analysis using a set of these markers could clearly discriminate MIS-C and COVID-19 from seropositive and control children. MIS-C children requiring pediatric intensive care unit admission and COVID-19 children with severe disease had higher levels of CRP, SAP, and/or sCD14 at admission. CONCLUSIONS: Our study describes the role of systemic inflammation and microbial translocation markers in children with MIS-C and COVID-19 and therefore helps in advancing our understanding of the pathogenesis of different presentations of SARS-CoV-2 infection in children
Neutrophil Extracellular TrapâDerived Enzymes Oxidize HighâDensity Lipoprotein: An Additional Proatherogenic Mechanism in Systemic Lupus Erythematosus
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108351/1/art38703.pd
Role of matrix metalloproteinases in multi-system inflammatory syndrome and acute COVID-19 in children
INTRODUCTION: Multisystem Inflammatory Syndrome in children (MIS-C) is a serious inflammatory sequela of SARS-CoV2 infection. The pathogenesis of MIS-C is vague and matrix metalloproteinases (MMPs) may have an important role. Matrix metalloproteinases (MMPs) are known drivers of lung pathology in many diseases. METHODS: To elucidate the role of MMPs in pathogenesis of pediatric COVID-19, we examined their plasma levels in MIS-C and acute COVID-19 children and compared them to convalescent COVID-19 and children with other common tropical diseases (with overlapping clinical manifestations). RESULTS: Children with MIS-C had elevated levels of MMPs (P < 0.005 statistically significant) in comparison to acute COVID-19, other tropical diseases (Dengue fever, typhoid fever, and scrub typhus fever) and convalescent COVID-19 children. PCA and ROC analysis (sensitivity 84â100% and specificity 80â100%) showed that MMP-8, 12, 13 could help distinguish MIS-C from acute COVID-19 and other tropical diseases with high sensitivity and specificity. Among MIS-C children, elevated levels of MMPs were seen in children requiring intensive care unit admission as compared to children not needing intensive care. Similar findings were noted when children with severe/moderate COVID-19 were compared to children with mild COVID-19. Finally, MMP levels exhibited significant correlation with laboratory parameters, including lymphocyte counts, CRP, D-dimer, Ferritin and Sodium levels. DISCUSSION: Our findings suggest that MMPs play a pivotal role in the pathogenesis of MIS-C and COVID-19 in children and may help distinguish MIS-C from other conditions with overlapping clinical presentation
Unique cellular immune signatures of multisystem inflammatory syndrome in children
The clinical presentation of MIS-C overlaps with other infectious/non-infectious diseases such as acute COVID-19, Kawasaki disease, acute dengue, enteric fever, and systemic lupus erythematosus. We examined the ex-vivo cellular parameters with the aim of distinguishing MIS-C from other syndromes with overlapping clinical presentations. MIS-C children differed from children with non-MIS-C conditions by having increased numbers of naĂŻve CD8(+) T cells, naĂŻve, immature and atypical memory B cells and diminished numbers of transitional memory, stem cell memory, central and effector memory CD4(+) and CD8(+) T cells, classical, activated memory B and plasma cells and monocyte (intermediate and non-classical) and dendritic cell (plasmacytoid and myeloid) subsets. All of the above alterations were significantly reversed at 6â9 months post-recovery in MIS-C. Thus, MIS-C is characterized by a distinct cellular signature that distinguishes it from other syndromes with overlapping clinical presentations. Trial Registration: ClinicalTrials.gov clinicaltrial.gov. No: NCT04844242