57 research outputs found
The role of caspases in Parkinson’s Disease pathogenesis: a brief look at the mitochondrial pathway
Parkinson’s disease (PD) is a neurodegenerative disorder
characterised by tremor, rigidity, Bradykinesia and reduced facial expression. Development of PD is considered to be the result of deficiency of the neurotransmitter dopamine, which is due to death of Dopamine-Containing Neurons (DCNs) that produce dopamine in the pars compacta region of the substantia nigra. Although the concentrated efforts of the scientific community over the last decades, the etiology of the death of DCN is yet to be understood. Oxidative stress has been considered as one of the causes of defects in the mitochondria leading to the dopaminergic cell damage [1]. Levodopa therapy is a well-known treatment for the symptoms of PD, however long term use of L-dopa causes side effects including further enhancement of oxidative stress [2]. The elevated levels of Reactive Oxidative Species (ROS) such as hydrogen peroxide, superoxide and hydroxyl ions, induce stimulation to the Permeability Transition Pore (mPTP) of the mitochondria leading to the collapse of the mitochondrial membrane potential and the release of cytochrome C. Furthermore, increased ROS activity promote nitric oxide binding to superoxide producing peroxynitrate enhancing oxidative and nitrosative stress, which results in DNA damage, chromosomal mutations, lipid peroxidation and enzyme defects [3]. Mutation of E3 ligase caused by peroxynitrate damage leads to impairment of ubiquitin-proteasome system, resulting in high levels of defective proteins, which accumulate in the Endoplasmic Reticulum (ER) promoting ER stress and ultimately cell death. Moreover, the apoptotic neuron triggers injury signals that activate microglia and promote release of cytokines such as interleukins-6 and -8. Subsequently, interleukins trigger Caspase activation along with inducible NO synthase, which further elevates formation of nitric oxide. Exposure to excessive reactive nitrite species along with enhanced production of ROS and peroxynitrate lead to dysfunction of complex-IV and complex-I activities of the mitochondria and promote mitochondrialmediated apoptosis through Caspase activation [4,5]
Modulation of LPS stimulated NF-kappaB mediated Nitric Oxide production by PKCε and JAK2 in RAW macrophages
<p>Abstract</p> <p>Background</p> <p>Nuclear factor kappa B (NF-κB) has been shown to play an important role in regulating the expression of many genes involved in cell survival, immunity and in the inflammatory processes. NF-κB activation upregulates inducible nitric oxide synthase leading to enhanced nitric oxide production during an inflammatory response. NF-κB activation is regulated by distinct kinase pathways independent of inhibitor of κB kinase (IKK). Here, we examine the role of protein kinase C isoforms and janus activated kinase 2 (JAK2) activation in NF-κB activation and LPS-stimulated NO production.</p> <p>Methods</p> <p>Murine RAW 264.7 macrophages were treated with lipopolysaccharide (LPS), Phorbol 12-myristate 13-acetate (PMA) and a combination of LPS and PMA in the presence or absence of various inhibitors of PKC isoforms and JAK2. Nuclear translocation of the NF-κB p65 subunit, was assessed by Western blot analysis whilst NO levels were assessed by Greiss assay.</p> <p>Results</p> <p>LPS-stimulated NO production was attenuated by PMA whilst PMA alone did not affect NO release. These effects were associated with changes in p65 nuclear translocation. The PKCα, β, γ, δ and ζ inhibitor Gö 6983 (Go) had no effect on LPS-induced NO release. In contrast, Bisindolymalemide I (Bis), a PKC α, β<sub>I</sub>, β<sub>II</sub>, γ, δ and ε isoform inhibitors completely inhibited LPS-stimulated NO production without affecting p65 nuclear translocation. Furthermore, a partial inhibitory effect on LPS-induced NO release was seen with the JAK2 inhibitor AG-490 and the p38 MAPK inhibitor SB 203850.</p> <p>Conclusion</p> <p>The results further define the role of NF-κB in LPS stimulated NO production in RAW macrophages. The data support a function for PKCε, JAK2 and p38 MAPK in NF-κB activation following p65 nuclear import.</p
Modulation of LPS stimulated NF-kappaB mediated Nitric Oxide production by PKCε and JAK2 in RAW macrophages
Nuclear factor kappa B (NF-κB) has been shown to play an important role in regulating the expression of many genes involved in cell survival, immunity and in the inflammatory processes. This paper details research in which Murine RAW 264.7 macrophages were treated with lipopolysaccharide (LPS), Phorbol 12-myristate 13-acetate (PMA) and a combination of LPS and PMA in the presence or absence of various inhibitors of PKC isoforms and JAK2. Nuclear translocation of the NF-κB p65 subunit, was assessed by Western blot analysis whilst NO levels were assessed by Greiss assay. The results of the research further define the role of NF-κB in LPS stimulated NO production in RAW macrophages. The data support a function for PKCε, JAK2 and p38 MAPK in NF-κB activation following p65 nuclear import
Neutralizing antibodies against SARS-CoV-2 are higher but decline faster in mRNA vaccinees compared to individuals with natural infection.
Waning protection against emerging SARS-CoV-2 variants by pre-existing antibodies elicited due to current vaccination or natural infection is a global concern. Whether this is due to the waning of immunity to SARS-COV-2 remains unclear. We aimed to investigate the dynamics of antibody isotype responses among vaccinated naïve (VN) and naturally infected (NI) individuals. We followed up antibody levels in COVID-19 mRNA-vaccinated subjects without prior infection (VN, n = 100) in two phases: phase-I (P-I) at ~ 1.4 and phase-II (P-II) at ~ 5.3 months. Antibody levels were compared to those of unvaccinated and naturally infected subjects (NI, n = 40) at ~ 1.7 (P-1) and 5.2 (P-II) months post-infection. Neutralizing antibodies (NTAb), anti-S-RBD-IgG, -IgM, and anti-S-IgA isotypes were measured. The VN group elicited significantly greater antibody responses (p < 0.001) than the NI group at P-I, except for IgM. In the VN group, a significant waning in antibody response was observed in all isotypes. There was about ~ a 4-fold decline in NTAb levels (p < 0.001), anti-S-RBD-IgG (~5-folds, p < 0.001), anti-S-RBD-IgM (~6-folds, p < 0.001), and anti-S1-IgA (2-folds, p < 0.001). In the NI group, a significant but less steady decline was notable in S-RBD-IgM (~2-folds, p < 0.001), and a much smaller but significant difference in NTAb (<2-folds, p < 0.001) anti-S-RBD IgG (<2-folds, p = 0.005). Unlike the VN group, the NI group mounted a lasting anti-S1-IgA response with no significant decline. Anti-S1-IgA, which were ~ 3 folds higher in VN subjects compared to NI in P-1 (p < 0.001), dropped to almost the same levels, with no significant difference observed between the two groups in P-II. While double-dose mRNA vaccination boosted antibody levels, vaccinated individuals' 'boost' was relatively short-lived.This work was made possible by WHO grant numbers COVID-19-22-43 and UREP28–173–3-057 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors
Validation of a Novel Fluorescent Lateral Flow Assay for Rapid Qualitative and Quantitative Assessment of Total Anti-SARS-CoV-2 S-RBD Binding Antibody Units (BAU) from Plasma or Fingerstick Whole-Blood of COVID-19 Vaccinees
Background: Limited commercial LFA assays are available to provide a reliable quantitative measurement of the total binding antibody units (BAU/mL) against the receptor-binding domain of the SARS-CoV-2 spike protein (S-RBD). Aim: This study aimed to evaluate the performance of the fluorescence LFA FinecareTM 2019-nCoV S-RBD test along with its reader (Model No.: FS-113) against the following reference methods: (i) the FDA-approved GenScript surrogate virus-neutralizing assay (sVNT); and (ii) three highly performing automated immunoassays: BioMérieux VIDAS®3, Ortho VITROS®, and Mindray CL-900i®. Methods: Plasma from 488 vaccinees was tested by all aforementioned assays. Fingerstick whole-blood samples from 156 vaccinees were also tested by FinecareTM. Results and conclusions: FinecareTM showed 100% specificity, as none of the pre-pandemic samples tested positive. Equivalent FinecareTM results were observed among the samples taken from fingerstick or plasma (Pearson correlation r = 0.9, p < 0.0001), suggesting that fingerstick samples are sufficient to quantitate the S-RBD BAU/mL. A moderate correlation was observed between FinecareTM and sVNT (r = 0.5, p < 0.0001), indicating that FinecareTM can be used for rapid prediction of the neutralizing antibody (nAb) post-vaccination. FinecareTM BAU results showed strong correlation with VIDAS®3 (r = 0.6, p < 0.0001) and moderate correlation with VITROS® (r = 0.5, p < 0.0001) and CL-900i® (r = 0.4, p < 0.0001), suggesting that FinecareTM can be used as a surrogate for the advanced automated assays to measure S-RBD BAU/mL.This work was made possible by grant number UREP28-173-3-057 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors
Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries
Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely
Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study
Purpose:
Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom.
Methods:
Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded.
Results:
The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8–4.6) in CFS 4 vs 1–3; OR 12.4 (6.2–24.5) in CFS 8 vs 1–3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3–1.9) in CFS 4 compared to 0.2 (0.1–0.7) in CFS 8). These risks were both independent of age and dementia.
Conclusion:
We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes
Exercise as a neuroprotective mechanism in Parkinson’s disease: future treatment potential?
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