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1.
Clin Chem Lab Med ; 61(8): 1511-1517, 2023 07 26.
Article in English | MEDLINE | ID: mdl-36799248

ABSTRACT

OBJECTIVES: To evaluate pre-analytical challenges related to high-volume central laboratory SARS-CoV-2 antigen testing with a prototype qualitative SARS-CoV-2 antigen immunoassay run on the automated Abbott ARCHITECT instrument. METHODS: Contrived positive and negative specimens and de-identified nasal and nasopharyngeal specimens in transport media were used to evaluate specimen and reagent on-board stability, assay analytical performance and interference, and clinical performance. RESULTS: TCID50/mL values were similar for specimens in various transport media. Inactivated positive clinical specimens and viral lysate (USA-WA1/2020) were positive on the prototype immunoassay. Within-laboratory imprecision was ≤0.10 SD (<1.00 S/C) with a ≤10% CV (≥1.00 S/C). Assay reagents were stable on board the instrument for 14 days. No high-dose hook effect was observed with a SARS-CoV-2 stock of Ct 13.0 (RLU>1.0 × 106). No interference was observed from mucin, whole blood, 12 drugs, and more than 20 cross-reactants. While specimen stability was limited at room temperature for specimens with or without viral inactivation, a single freeze/thaw cycle or long-term storage (>30 days) at -20 °C did not adversely impact specimen stability or assay performance. Specificity of the prototype SARS-CoV-2 antigen immunoassay was ≥98.5% and sensitivity was ≥89.5% across two ARCHITECT instruments. Assay sensitivity was inversely correlated with Ct and was similar to that reported for the Roche Elecsys® SARS-CoV-2 Ag immunoassay. CONCLUSIONS: The prototype SARS-CoV-2 antigen ARCHITECT immunoassay is sensitive and specific for detection of SARS-CoV-2 in nasal and nasopharyngeal specimens. Endogenous proteases in mucus may degrade the target antigen, which limits specimen storage and transport times and complicates assay workflow.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , COVID-19/diagnosis , Sensitivity and Specificity , COVID-19 Testing , Immunoassay
2.
Harefuah ; 159(6): 391-393, 2020 Jun.
Article in Hebrew | MEDLINE | ID: mdl-32583639

ABSTRACT

INTRODUCTION: SARS-CoV-2 is dispersed from patients by talking, coughing and sneezing. The generated micro-droplets aerosols can travel up to 8 meters, stay suspended for long periods and preserve viral infectivity for a median of 2.7 hours. An unprotected person exposed to this cloud, might inhale a considerable amount of infectious viral doses, which will attach to the ACE 2 receptors on alveoli epithelium, resulting in infection. N95 respirators and surgical masks block 95% and 50-60% respectively of inhalable particles and protect the wearer from infection. Surgical masks and N95 without exhalation valve, protect both the wearer and the environment from carriers and sick people.


Subject(s)
Aerosols , Coronavirus Infections/prevention & control , Coronavirus Infections/transmission , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Pneumonia, Viral/transmission , Respiratory Protective Devices , Risk Assessment , Betacoronavirus , COVID-19 , Humans , SARS-CoV-2
3.
Hum Mol Genet ; 25(11): 2143-2157, 2016 06 01.
Article in English | MEDLINE | ID: mdl-27000625

ABSTRACT

Intermediate filaments (IFs) are cytoskeletal polymers that extend from the nucleus to the cell membrane, giving cells their shape and form. Abnormal accumulation of IFs is involved in the pathogenesis of number neurodegenerative diseases, but none as clearly as giant axonal neuropathy (GAN), a ravaging disease caused by mutations in GAN, encoding gigaxonin. Patients display early and severe degeneration of the peripheral nervous system along with IF accumulation, but it has been difficult to link GAN mutations to any particular dysfunction, in part because GAN null mice have a very mild phenotype. We therefore established a robust dorsal root ganglion neuronal model that mirrors key cellular events underlying GAN. We demonstrate that gigaxonin is crucial for ubiquitin-proteasomal degradation of neuronal IF. Moreover, IF accumulation impairs mitochondrial motility and is associated with metabolic and oxidative stress. These results have implications for other neurological disorders whose pathology includes IF accumulation.


Subject(s)
Cytoskeletal Proteins/genetics , Giant Axonal Neuropathy/genetics , Intermediate Filament Proteins/genetics , Intermediate Filaments/genetics , Animals , Disease Models, Animal , Energy Metabolism/genetics , Giant Axonal Neuropathy/pathology , Humans , Intermediate Filament Proteins/biosynthesis , Intermediate Filaments/pathology , Mice , Mitochondria/genetics , Mitochondria/pathology , Neurons/metabolism , Neurons/pathology , Oxidative Stress/genetics , Proteasome Endopeptidase Complex/genetics , Proteasome Endopeptidase Complex/metabolism , Proteolysis
7.
Harefuah ; 154(2): 129-32, 134, 2015 Feb.
Article in Hebrew | MEDLINE | ID: mdl-25856869

ABSTRACT

The entity 'sick building syndrome' is poorly defined and comprises of a set of symptoms resulting from environmental exposure to a work or a living environment. The symptoms are mainly "allergic"-like and include nasal, eye, and mucous membrane irritation, dry skin as well as respiratory symptoms and general symptoms such as fatigue, lethargy, headaches and fever. The Autoimmune [Auto-inflammatory] Syndrome Induced by Adjuvants (ASIA) is a wider term which describes the role of various environmental factors in the pathogenesis of immune mediated diseases. Factors entailing an immune adjuvant activity such as infectious agents, silicone, aluminium salts and others were found in association with defined and non-defined immune mediated diseases. The sick building syndrome and ASIA share a similar complex of signs and symptoms and probably the same immunological mechanisms which further support a common denominator.


Subject(s)
Adjuvants, Immunologic/adverse effects , Autoimmune Diseases/immunology , Sick Building Syndrome/immunology , Autoimmune Diseases/epidemiology , Environmental Exposure/adverse effects , Humans , Occupational Diseases/epidemiology , Occupational Diseases/immunology , Occupational Exposure/adverse effects , Sick Building Syndrome/epidemiology
8.
Neurobiol Dis ; 70: 90-8, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24905915

ABSTRACT

While α-Synuclein (α-Syn) is mainly detected as a cytosolic protein, a portion of it is recovered bound to membranes. It is suggested that binding to membrane phospholipids controls α-Syn structure, physiology and pathogenesis. We aimed at investigating the role, of the positive charged lysine residues at the KTKEGV repeat motif, in mediating α-Syn associations with membrane phospholipids and in α-Syn oligomerization and aggregation. Specifically, two positive lysine (K) residues were replaced with two negative glutamic acid (E) residues at either the first or second KTKEGV repeat motifs. The effect of these mutations on membrane binding was determined by a quantitative phospholipid ELISA assay and compared to wild-type α-Syn and to the Parkinson's disease-causing mutations, A30P, E46K and A53T. We found that the K to E substitutions affected α-Syn binding to phospholipids. In addition, K to E substitutions resulted in a dramatically lower level of soluble α-Syn oligomers and larger intracellular inclusions. Together, our results suggest a critical role for lysine residues at the N-terminal repeat domain in the pathophysiology of α-Syn.


Subject(s)
Cell Membrane/metabolism , Phospholipids/metabolism , alpha-Synuclein/genetics , alpha-Synuclein/metabolism , Amino Acid Sequence , Animals , Brain/metabolism , Cell Line , HEK293 Cells , Humans , Mice, Inbred C3H , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Molecular Sequence Data , Mutation , Parkinson Disease/genetics
10.
Harefuah ; 153(8): 443-4, 499, 2014 Aug.
Article in Hebrew | MEDLINE | ID: mdl-25286630

ABSTRACT

An Israeli researcher working in Finland with Bank Voles, contracted an infectious viral disease and died. This was a rare event, but it is important to learn about this class of viruses and to be aware of the hazards while working in the field in close contact with wild animals. The virus termed Puumala belongs to the genus Hanta from the Bunyaviridae family. The natural reservoir is rodents, mice, rats and Bank Votes for the Puuamala strain. The disease is termed HFRS (hemorrhagic fever with renal syndrome), is prevalent in Asia and Europe, affecting 200,000 people a year, with 5-15% percent mortality (although in Finland mortality rate is 0.1%). The New World strains cause HPS (hemorrhagic pulmonary syndrome) affecting 200 people a year with 40% mortality. Virus is present in all rodents excretions, and route of infection is by aerosols, hand to mucus membranes contamination, by rodents bites and by contaminated food or water. More than 226 work related infections were documented. Treatment with Ribavirin helps in HFRS but not in HPS. The virus is stable in the environment for long periods, and research must be carried out at biosafety level 3. Working outdoors in rodent infested area, should be carried out using protective clothing, gloves, googles and face mask whenever aerosol producing tasks are performed. Both indoor and outdoor, it is important to adhere to self-hygienic procedures, especially hand washing.


Subject(s)
Hazard Analysis and Critical Control Points/methods , Hemorrhagic Fever with Renal Syndrome , Puumala virus/pathogenicity , Ribavirin/therapeutic use , Animals , Antiviral Agents/therapeutic use , Disease Reservoirs , Disease Vectors , Finland/epidemiology , Hemorrhagic Fever with Renal Syndrome/mortality , Hemorrhagic Fever with Renal Syndrome/physiopathology , Hemorrhagic Fever with Renal Syndrome/prevention & control , Hemorrhagic Fever with Renal Syndrome/virology , Humans , Mice , Rats , Research Personnel
11.
bioRxiv ; 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-39416015

ABSTRACT

Influenza represents one of the biggest health threats facing humanity. Seasonal epidemics can transition to global pandemics, with cross-species infection presenting a continuous challenge. Although vaccines and several anti-viral options are available, constant genetic drifts and shifts vitiate any of the aforementioned prevention and treatment options. Therefore, we describe an approach targeted at the virus's channel to derive new anti-viral options. Specifically, Influenza A's M2 protein is a well-characterized channel targeted for a long time by aminoadamantane blockers. However, widespread mutations in the protein render the drugs ineffective. Consequently, we started by screening a repurposed drug library against aminoadamantane-sensitive and resistant M2 channels using bacteria-based genetic assays. Subsequent in cellulo testing and structure-activity relationship studies yielded a combination of Theobromine and Arainosine, which exhibits stark anti-viral activity by inhibiting the virus's channel. The drug duo was potent against H1N1 pandemic swine flu, H5N1 pandemic avian flu, aminoadamantane-resistant and sensitive strains alike, exhibiting activity that surpassed Oseltamivir, the leading anti-flu drug on the market. When this drug duo was tested in an animal model, it once more outperformed Oseltamivir, considerably reducing disease symptoms and viral RNA progeny. In conclusion, the outcome of this study represents a new potential treatment option for influenza alongside an approach that is sufficiently general and readily applicable to other viral targets.

12.
Harefuah ; 157(12): 748-750, 2018 Dec.
Article in Hebrew | MEDLINE | ID: mdl-30582304
15.
Harefuah ; 152(4): 188-9, 249, 2013 Apr.
Article in Hebrew | MEDLINE | ID: mdl-23844515

ABSTRACT

Clostridium difficile is the etiologic agent of nosocomial and community-acquired diarrhea associated with exposure to antibiotics that disrupt the normal colonic flora. As antibacterials currently used for primary C. difficile infections favor recurrences, new methods able to neutralize the bacterium without affecting the gut microbiota are badly needed. Complementary treatment with probiotic agents to reconstitute the physiologicaL intestinal flora does not yield any consistent benefit. In recent years, fecal transplantation has been used in the English-speaking countries with cure rates of about 87%. Fecal microbiota transplantation (FMT) holds considerable promise as a therapy for recurrent Clostridium difficile infection, but well-designed, randomized-controlled trials and Long-term follow-up registries are stilt required. These are needed to identify the right patient, efficacy and safety profile of FMT before this approach can be widely advocated. Another aspect of bad/good parasites are the use of helminth or helminth ova for treating autoimmune diseases, especially those affecting the gut.


Subject(s)
Anti-Bacterial Agents/adverse effects , Enterocolitis, Pseudomembranous/microbiology , Enterocolitis , Gastrointestinal Contents , Probiotics/therapeutic use , Anti-Bacterial Agents/administration & dosage , Clostridioides difficile/isolation & purification , Clostridioides difficile/pathogenicity , Enterocolitis/etiology , Enterocolitis/therapy , Gastrointestinal Contents/drug effects , Gastrointestinal Contents/microbiology , Humans , Lactobacillus/drug effects , Lactobacillus/physiology
16.
Harefuah ; 156(12): 748-750, 2017 Dec.
Article in Hebrew | MEDLINE | ID: mdl-29292610
17.
J Immunol Methods ; 504: 113262, 2022 05.
Article in English | MEDLINE | ID: mdl-35341761

ABSTRACT

OBJECTIVES: Quantitative detection of interleukin-6 (IL-6) in serum and plasma can help monitor immune responses and the development of acute inflammation to guide patient management. We developed an IL-6 immunoassay for use with the automated ARCHITECT system for detecting an increase in the inflammatory response. METHODS: Immunized mouse sera were tested and selected B-cells were harvested for fusion with myeloma cells. A panel of monoclonal antibodies were produced, from which capture and detection monoclonal antibodies for the prototype IL-6 immunoassay were selected and screened on the ARCHITECT instrument. The antibody pair that most effectively captured and detected IL-6 was selected to develop a prototype IL-6 immunoassay. Calibrator and panel preparations using an internal recombinant IL-6 standard were compared to serum panels prepared with the IL-6 International Standard 89/548. Assay specificity and spike recovery were determined, and assay sensitivity was compared with the Roche EUA Elecsys IL-6 assay run on the cobas analyzer. RESULTS: Twenty-one antibodies in 441 antibody pairs were screened. The prototype IL-6 assay showed high sensitivity with an estimated limit of detection of 0.317 pg/mL and limit of quantitation of <1.27. Spike recovery was 90%-110% in serum and plasma. The internal recombinant human IL-6 calibrator showed excellent stability for 63 days at 2-8 °C. The prototype IL-6 immunoassay was specific for IL-6, exhibited no cross reactivity to related cytokines and interleukins, and was 10-fold more sensitive than the Elecsys IL-6 assay. CONCLUSIONS: The prototype ARCHITECT IL-6 automated immunoassay is a reliable and robust method for the quantitative determination of IL-6 in human serum and plasma.


Subject(s)
Immunologic Tests , Interleukin-6 , Animals , Antibodies, Monoclonal , Humans , Immunoassay/methods , Immunologic Factors , Mice , Sensitivity and Specificity
18.
Traffic ; 10(2): 218-34, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18980610

ABSTRACT

Alpha-synuclein (alphaS) is an abundant neuronal cytoplasmic protein implicated in Parkinson's disease (PD), but its physiological function remains unknown. Consistent with its having structural motifs shared with class A1 apolipoproteins, alphaS can reversibly associate with membranes and help regulate membrane fatty acid composition. We previously observed that variations in alphaS expression level in dopaminergic cultured cells or brains are associated with changes in polyunsaturated fatty acid (PUFA) levels and altered membrane fluidity. We now report that alphaS acts with PUFAs to enhance the internalization of the membrane-binding dye, FM 1-43. Specifically, alphaS expression coupled with exposure to physiological levels of certain PUFAs enhanced clathrin-mediated endocytosis in neuronal and non-neuronal cultured cells. Moreover, alphaS expression and PUFA-enhanced basal and -evoked synaptic vesicle (SV) endocytosis in primary hippocampal cultures of wild type (wt) and genetically depleted alphaS mouse brains. We suggest that alphaS and PUFAs normally function in endocytic mechanisms and are specifically involved in SV recycling upon neuronal stimulation.


Subject(s)
Clathrin/metabolism , Endocytosis , Fatty Acids, Unsaturated/metabolism , Synaptic Vesicles/metabolism , alpha-Synuclein/metabolism , Animals , Cell Line , Cell Membrane/metabolism , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Neurons/metabolism , Protein Multimerization , Protein Transport , Receptors, Transferrin/metabolism , Solubility , Tissue Culture Techniques , Transferrin/metabolism , alpha-Synuclein/deficiency , alpha-Synuclein/genetics
19.
Mod Rheumatol ; 21(3): 235-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21188456

ABSTRACT

Sick building syndrome (SBS) is a term coined for a set of clinically recognizable symptoms and ailments without a clear cause reported by occupants of a building. In the 1990s the term "functional somatic syndromes" was applied to several syndromes, including SBS, multiple chemical sensitivity, repetition stress injury, the side effects of silicone breast implants, the Gulf War syndrome (GWS), chronic fatigue syndrome, the irritable bowel syndrome, and fibromyalgia. Recently, Shoenfeld and Agmon-Levin suggested that four conditions--siliconosis, macrophagic myofascitis, the GWS, and post-vaccination phenomena--which share clinical and pathogenic resemblances, may be included under a common syndrome entitled the "autoimmune (auto-inflammatory) syndrome induced by adjuvants". Comparison of the clinical manifestations, symptoms, and signs of the four conditions described by Shoenfeld and Agmon-Levin with those described for SBS shows that nine out of ten main symptoms are present in all 5 conditions. Shoenfeld and Agmon-Levin further propose several major and minor criteria, which, although requiring further validation, may aid in the diagnosis of this newly defined syndrome. We propose here that SBS may also be included as a part of "Shoenfeld's syndrome".


Subject(s)
Adjuvants, Immunologic/adverse effects , Autoimmune Diseases/epidemiology , Autoimmune Diseases/immunology , Sick Building Syndrome/epidemiology , Sick Building Syndrome/immunology , Humans , Prevalence
20.
Biotechniques ; 71(1): 370-375, 2021 07.
Article in English | MEDLINE | ID: mdl-34139879

ABSTRACT

Inactivation of SARS-CoV-2 virus is necessary to mitigate risk but may interfere with diagnostic assay performance. We examined the effect of heat inactivation on a prototype SARS-CoV-2 antigen immunoassay run on the ARCHITECT automated analyzer. Recombinant full-length SARS-CoV-2 nucleocapsid protein and virus lysate detection was reduced by 66 and 31%, respectively. Several nonionic detergents were assessed as inactivation alternatives based on infectivity in cultured Vero CCL81 cells. Incubation of SARS-CoV-2 in 0.1% Tergitol 15-S-9 for 10 min significantly reduced infectivity and increased the immunoassay signal for cultured lysate and patient specimens. Tergitol 15-S-9 can inactivate SARS-CoV-2 while preserving epitopes on the nucleocapsid protein for enhanced detection by immunoassay antibodies.


Subject(s)
COVID-19 Testing/methods , Poloxalene/pharmacology , SARS-CoV-2/drug effects , SARS-CoV-2/immunology , Virus Inactivation/drug effects , Animals , Antibodies, Viral/drug effects , Antibodies, Viral/immunology , COVID-19/diagnosis , COVID-19/immunology , COVID-19 Testing/standards , Cells, Cultured , Chlorocebus aethiops , Humans , Immunoassay/methods , Immunoassay/standards , Nucleocapsid/immunology , Surface-Active Agents/pharmacology , Vero Cells
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