Effect of natalizumab on oxidative damage biomarkers in relapsing-remitting multiple sclerosis

BackgroundNatalizumab is a monoclonal antibody used to treat multiple sclerosis. This study sought to determine whether the protective action of natalizumab involved a reduction in oxidative damage.MethodsTwenty-two multiple sclerosis patients fulfilling the revised McDonald criteria were assigned to treatment with 300 mg natalizumab intravenously once monthly (infusion every 4 weeks) in accordance with Spanish guidelines. Carbonylated proteins, 8-hydroxy-2’-deoxyguanosine, total glutathione, reduced glutathione, superoxide dismutase, glutathione peroxidase, and myeloperoxidase levels were measured at baseline and after 14 months’ treatment, and the antioxidant gap was calculated.ResultsNatalizumab prompted a drop in oxidative-damage biomarker levels, together with a reduction both in myeloperoxidase levels and in the myeloperoxidase/neutrophil granulocyte ratio. Interestingly, natalizumab induced nuclear translocation of Nrf2 and a fall in serum vascular cell adhesion molecule-1 levels.ConclusionThese findings suggest that natalizumab has a beneficial effect on oxidative damage found in MS patients.     

Analysis of bleomycin-induced mutagenic functions related to the PSO4 (= xs9) gene of Saccharomyces cerevisiae.

In the present work we analyse some properties of the pso4-1 (= xs9) mutant of the yeast Saccharomyces cerevisiae, which is blocked in both reverse mutation and recombination. We have applied the "apparent survival test" as a method to characterize putative inducible error-prone repair activities related to the PSO4 gene. As the mutagenic agent we have used bleomycin, which is an antitumour radiomimetic antibiotic. Survival, reverse mutation yield, and reverse mutation frequency were determined as a function of bleomycin concentrations (1-60 micrograms/ml) in the logarithmic phase of growth. It is shown that the PSO4 gene product is poorly involved in bleomycin sensitivity and that reverse mutation induced by this mutagen is dramatically reduced in the pso4-1 lys2 mutant strain, as compared with the isogenic SC7K (lys2) strain. M(x) functions exhibit linear-quadratic courses for both the SC7K (lys2) and the pso4-1 lys2 strains. The apparent survival functions display "humps" in both strains, corresponding to the resistant components of the survival functions. These facts suggest that the mutagenicity of bleomycin depends on at least one inducible error-prone repair pathway and that the PSO4 gene product could act as a mutation triggering factor.     

Evaluation of the detection of human papillomavirus genotypes in cervical specimens by hybrid capture as screening for precancerous lesions in HIV-positive women

Given the frequency and persistence of human papillomavirus (HPV) infection and associated cytological alterations in HIV-1-positive women, the incidence of uterine cervix neoplasm is likely to increase along with patient survival. More appropriate screening programs, which, in addition to Pap smears (PS), also include tests to detect and type HPV, are needed for the early identification of precancerous cervical lesions. This prospective study involved 168 HIV-positive (group A) and 100 HIV-negative women (group B). Cervicovaginal samples were collected for a PS and HPV DNA search. The detected virus was typed as high–intermediate oncogenic risk HPV (HR-HPV) and low-risk HPV (LR-HPV) using hybrid capture (HC) (Murex-Digene) and in-house PCR tests. The HC-detected prevalence of HPV was 111/168 (66%:HR 75.6%) in group A and 15/100 (15%:HR 42.9%) in group B (P < 0.0001). Polymerase chain reaction (PCR) was positive in 91% and 48%, respectively. No significant difference was observed between drug addicts and heterosexual HIV-1-positive women (P = 0.09). HPV was detected in 94% of the 57 HIV-positive women with cytological alterations. HR-HPV was found in 41/49 women with low-grade and 7/8 with high-grade squamous intraepithelial lesions (LSIL and HSIL, respectively). In women with a negative PS, HPV was detected in 57/111 cases (HR 63%) of group A and in 13/98 of group B (6 cases of HR). Of the 54 group A women who underwent biopsy, histology revealed that 41 had LSIL (18 with negative PS, 19 with LSIL, and 4 with HSIL; HR-HPV in 73% and LR-HPV in 17%), nine had HSIL (5 LSIL and 4 HSIL on cytology; HR-HPV in 89% and LR-HPV in 11%), and four were negative (all cytology negative; 3 HR-HPV and 1 LR-HPV). HR-HPV was more frequent as immunodepression worsened. These results show that cytological evaluation alone underestimated histological alterations in 23/50 women (42.6%), whereas the combination of Pap smear and HPV detection reduced this underestimate to 5%. J. Med. Virol. 56:133–137, 1998. © 1998 Wiley-Liss, Inc.     

Duplex Doppler ultrasound study of the temporomandibular joint

IntroductionThe anatomy and physiology of the temporomandibular joint can be studied clinically and by diagnostic imaging. Magnetic resonance imaging (MRI), radiography (X-ray) and computed tomography (CT) have thus for many years contributed to the study of the kinetics in the mandibular condyle. However, also duplex Doppler ultrasound (US) examination is widely used in the study of structures during movement, particularly vascular structures.Materials and methodsA total of 30 patients were referred by the Department of Orthodontics to the Department of Radiological, Oncological and Pathological Sciences, University of Rome “La Sapienza”. All patients underwent duplex Doppler ultrasound (US) examination of the temporomandibular joint using Toshiba APLIO SSA-770A equipment and duplex Doppler multi-display technique, which allows simultaneous display of US images and color Doppler signals. A linear phased array probe with crystal elements was used operating at a basic frequency of 6 MHz during pulsed Doppler spectral analysis and 7.5 MHz during US imaging.ResultsIn normal patients a regular alternation in the spectral Doppler waveforms was obtained, while in patients with temporomandibular joint meniscus dysfunction there was no regularity in the sum of the Fourier series with an unsteady waveform pattern related to irregular movements of the temporomandibular joint.ConclusionsIn all cases duplex Doppler US examination proved able to differentiate between normal and pathological patients and among the latter this technique permitted identification of the most significant aspects of the dysfunctional diseases.     

Analytical performance of a sensitive assay for cardiac troponin I with loci™ technology

ObjectivesTo confirm the analytical performance of the Dimension Vista LOCI troponin I assay (cTnI).Design and methodLimit of blank (LoB), limit of detection (LoD), limit of quantitation (LoQ) with a 10% coefficient of variation (CV), linearity, precision, method comparison, and 99th percentile upper reference limits (URL) were analyzed. Endogenous analytes and rheumatoid factor (RF) were tested for assay interference.ResultsThe 99th percentile was 0.022 µg/L (CV = 14%) and the LoQ was 0.036 µg/L. The ratio of 10% CV concentration to 99th percentile was 1.63. Linearity extended from 0 to 44.36 µg/L. The method comparison equation was Dimension® Vista? = 0.94 (Dimension® RxL) + 0.00 µg/L with bias at low levels. No interference was detected.ConclusionsThis study shows acceptable performance characteristics of the LOCI cTnI assay on Dimension® Vista? to diagnosis and risk stratification of patients with acute coronary syndrome symptoms.     

Novel Interactions Involving the Mas Receptor Show Potential of the Renin–Angiotensin system in the Regulation of Microglia Activation: Altered Expression in Parkinsonism and Dyskinesia

The renin–angiotensin system (RAS) not only plays an important role in controlling blood pressure but also participates in almost every process to maintain homeostasis in mammals. Interest has recently increased because SARS viruses use one RAS component (ACE2) as a target-cell receptor. The occurrence of RAS in the basal ganglia suggests that the system may be targeted to improve the therapy of neurodegenerative diseases. RAS-related data led to the hypothesis that RAS receptors may interact with each other. The aim of this paper was to find heteromers formed by Mas and angiotensin receptors and to address their functionality in neurons and microglia. Novel interactions were discovered by using resonance energy transfer techniques. The functionality of individual and interacting receptors was assayed by measuring levels of the second messengers cAMP and Ca²⁺ in transfected human embryonic kidney cells (HEK-293T) and primary cultures of striatal cells. Receptor complex expression was assayed by in situ proximity ligation assay. Functionality and expression were assayed in parallel in primary cultures of microglia treated or not with lipopolysaccharide and interferon-γ (IFN-γ). The proximity ligation assay was used to assess heteromer expression in parkinsonian and dyskinetic conditions. Complexes formed by Mas and the angiotensin AT₁ or AT₂ receptors were identified in both a heterologous expression system and in neural primary cultures. In the heterologous system, we showed that the three receptors—MasR, AT₁R, and AT₂R—can interact to form heterotrimers. The expression of receptor dimers (AT₁R-MasR or AT₂R-MasR) was higher in microglia than in neurons and was differentially affected upon microglial activation with lipopolysaccharide and IFN-γ. In all cases, agonist-induced signaling was reduced upon coactivation, and in some cases just by coexpression. Also, the blockade of signaling of two receptors in a complex by the action of a given (selective) receptor antagonist (cross-antagonism) was often observed. Differential expression of the complexes was observed in the striatum under parkinsonian conditions and especially in animals rendered dyskinetic by levodopa treatment. The negative modulation of calcium mobilization (mediated by AT₁R activation), the multiplicity of possibilities on RAS affecting the MAPK pathway, and the disbalanced expression of heteromers in dyskinesia yield new insight into the operation of the RAS system, how it becomes unbalanced, and how a disbalanced RAS can be rebalanced. Furthermore, RAS components in activated microglia warrant attention in drug-development approaches to address neurodegeneration.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13311-020-00986-4.Key Words: Parkinson, microglia, Mas receptor, GPCR, angiotensin, angiotensin AT₁ receptor, angiotensin AT₂ receptor