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Electrical matrix stimulation suppresses acute itch independently of activation of sleeping nociceptors. Eur J Pain 2024; 28:285-296. [PMID: 37715607 DOI: 10.1002/ejp.2177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/24/2023] [Accepted: 08/19/2023] [Indexed: 09/17/2023]
Abstract
INTRODUCTION Itch can be reduced by pain. Activation of sleeping nociceptors (CMi) is a crucial mechanism for the peripheral component of intense and long-lasting pain. Thus, activation of CMi might be especially effective in itch reduction. Electrical stimulation using sinusoidal pulses activates CMi with tolerable pain intensity, whereas short rectangular pulses with low intensity do not. In humans, histaminergic itch is mediated by histamine-sensitive CMi, whereas other pruritogens activate polymodal nociceptors (CM). METHODS In a psychophysical approach in a balanced crossover repeated-measures design in healthy volunteers, we activated nociceptors by two different electrical stimulation paradigms via a matrix electrode: 4 Hz sinusoidal pulses that activate C-nociceptors including CMi or 4 Hz rectangular stimuli to activate nociceptors excluding CMi. After 5-min stimulation, itch was induced by either histamine iontophoresis or application of cowhage spicules. Itch ratings were assessed via a numerical rating scale (NRS). RESULTS Electrical 4 Hz sine wave stimulation (0.1 mA) with low pain ratings of 1.5 (NRS; 0-10) induced an axon reflex erythema (3 cm2 ), indicating activation of CMi, whereas rectangular 0.2 ms pulses (average 0.91 mA) with the same pain rating did not. Both electrical stimulation paradigms reduced itch magnitude over time evoked by either histamine or cowhage to a similar extent. Peak maximum itch evoked by histamine was reduced by both stimulation paradigms, but not cowhage maximum itch. DISCUSSION Since electrical stimulation with the rectangular pulse paradigm reduces itch to a similar extent as the sine wave stimulation paradigm, the input of CMi is not necessarily required for itch suppression. The input of A-fibres and polymodal nociceptors, similarly, as also achieved by scratching, seems to be sufficient for both forms of chemically evoked itch. SIGNIFICANCE Since activation of CMi does not provide additional benefit for itch suppression, spinal pain pathways transmitted via CM versus CMi have differential effects on itch-processing circuits. This is important knowledge for using electrical matrix stimulation as itch suppressor since activation of sleeping nociceptors either requires significantly painful stimulation paradigms or specialized stimulation paradigms as sinusoidal pulses. An alternative approach using half-sine wave pulses with low pain intensity activating specifically polymodal nociceptors to suppress itch via matrix electrode stimulation may be considered.
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Electrophysiological characterization of schizophrenia-associated variants in NaV1.2 sodium channel. Eur Psychiatry 2022. [PMCID: PMC9568033 DOI: 10.1192/j.eurpsy.2022.1967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Introduction A major pathophysiological hypothesis of schizophrenia states an increased activity of glutamatergic neurons leading to an imbalance of neural excitation and inhibition (E/I-imbalance). One potential molecular mechanism of E/I-imbalance is a dysfunction of voltage-gated sodium channels, which are crucial for the generation of action potentials, the fundamental event of neuronal excitation. Indeed, patients with schizophrenia exhibit an increased burden of rare exonic variants of sodium channel genes, but the literature describing their electrophysiological effect is scarce. Objectives The aim of this project is to assess the functional impact of three mutations of the Sodium Voltage-Gated Channel Alpha Subunit 2 (SCN2A) gene / NaV1.2 channel which were identified in four patients with schizophrenia, using a heterologous expression system. Methods Three variants of the human SCN2A gene (R850P, V1282F and S1656P) were created using site-directed mutagenesis. HEK293T cells transfected with either the mutant or wild type constructs are being investigated by voltage-clamp technique, applying activation, steady-state fast inactivation, use dependency and ramp protocols. Results All three mutated constructs were successfully created. Preliminary recordings from the V1282F mutant indicate a shift of both the activation and steady-state fast inactivation to the hyperpolarized direction. Conclusions In a subgroup of patients, E/I imbalance may be a consequence of Nav1.2 mutations leading to increased excitability of glutamatergic neurons. By integrating insights from different mutations we aim to identify traits of a potentially shared disease pathway which may provide a basis for the development of novel therapeutics. Disclosure No significant relationships.
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An ecotoxicological view on neurotoxicity assessment. ENVIRONMENTAL SCIENCES EUROPE 2018; 30:46. [PMID: 30595996 PMCID: PMC6292971 DOI: 10.1186/s12302-018-0173-x] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 10/31/2018] [Indexed: 05/04/2023]
Abstract
The numbers of potential neurotoxicants in the environment are raising and pose a great risk for humans and the environment. Currently neurotoxicity assessment is mostly performed to predict and prevent harm to human populations. Despite all the efforts invested in the last years in developing novel in vitro or in silico test systems, in vivo tests with rodents are still the only accepted test for neurotoxicity risk assessment in Europe. Despite an increasing number of reports of species showing altered behaviour, neurotoxicity assessment for species in the environment is not required and therefore mostly not performed. Considering the increasing numbers of environmental contaminants with potential neurotoxic potential, eco-neurotoxicity should be also considered in risk assessment. In order to do so novel test systems are needed that can cope with species differences within ecosystems. In the field, online-biomonitoring systems using behavioural information could be used to detect neurotoxic effects and effect-directed analyses could be applied to identify the neurotoxicants causing the effect. Additionally, toxic pressure calculations in combination with mixture modelling could use environmental chemical monitoring data to predict adverse effects and prioritize pollutants for laboratory testing. Cheminformatics based on computational toxicological data from in vitro and in vivo studies could help to identify potential neurotoxicants. An array of in vitro assays covering different modes of action could be applied to screen compounds for neurotoxicity. The selection of in vitro assays could be guided by AOPs relevant for eco-neurotoxicity. In order to be able to perform risk assessment for eco-neurotoxicity, methods need to focus on the most sensitive species in an ecosystem. A test battery using species from different trophic levels might be the best approach. To implement eco-neurotoxicity assessment into European risk assessment, cheminformatics and in vitro screening tests could be used as first approach to identify eco-neurotoxic pollutants. In a second step, a small species test battery could be applied to assess the risks of ecosystems.
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Modelling activity-dependent changes of velocity in C-fibers. Scand J Pain 2017. [DOI: 10.1016/j.sjpain.2017.04.062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Aims
When C-nociceptors are activated repeatedly using electrical stimulation at relatively low frequencies (0.125–2 Hz), their propagation velocity will decrease. This is referred to as activity-dependent slowing (ADS). The main reason why activity-dependent changes in velocity are of interest is that they can be recorded directly, using invasive methods (microneurography), in patients with chronic pain. Interestingly, in certain patients with neuropathic pain, reduced activity-dependent slowing of conduction has been observed, indicating that these axons have an increased excitability. Through a computational model, it is possible to link such velocity alterations with changes in active conductances, opening for an understanding the underlying excitability changes occurring in these patients.
Methods
We have developed a detailed multicompartment model of a C-nociceptor fiber. This model incorporates a wide range of voltage-gated ion channels (Nav1.7, Nav1.8, Nav1.9, K
dr, K
A, K
M, K
Na and h) which were implemented across a detailed and realistic axon morphology.
Results
The model predicts that the small diameter of the axon can accumulate intracellular sodium when it is repeatedly activated in a similar fashion as during single fiber microneurography. This increase of intracellular sodium concentration can shift the balance between ion channel currents, shift the membrane potential and membrane input resistance, and thereby generate activity-dependent changes of velocity, such as ADS as well as recovery cycle supernormality.
Conclusions
Our results thus provide insight into how activity-dependent excitability changes can be generated in C-fibers. By identifying which ion channels are contributing to activity-dependent changes of velocity this could provide insight into ion channel alterations in neuropathic pain patients.
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DI-035 Should we make patients and nurses aware of their drug administration problems and training needs? Eur J Hosp Pharm 2015. [DOI: 10.1136/ejhpharm-2015-000639.211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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The opioid methadone induces a local anaesthetic-like inhibition of the cardiac Na⁺ channel, Na(v)1.5. Br J Pharmacol 2014; 171:427-37. [PMID: 24117196 DOI: 10.1111/bph.12465] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 09/23/2013] [Accepted: 09/27/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Treatment with methadone is associated with severe cardiac arrhythmias, a side effect that seems to result from an inhibition of cardiac hERG K⁺ channels. However, several other opioids are inhibitors of voltage-gated Na⁺ channels. Considering the common assumption that an inhibition of the cardiac Na⁺ channel Na(v)1.5, is the primary mechanism for local anaesthetic (LA)-induced cardiotoxicity, we hypothesized that methadone has LA-like properties leading to a modulation of Na(v)1.5 channels. EXPERIMENTAL APPROACH The whole-cell patch clamp technique was applied to investigate the effects of methadone on wild-type and mutant human Na(v)1.5 channels expressed in HEK293 cells. A homology model of human Na(v)1.5 channels was used to perform automated ligand-docking studies. KEY RESULTS Methadone inhibited Na(v)1.5 channels in a state-dependent manner, that is, tonic block was stronger with inactivated channels than with resting channels and a use-dependent block at 10 Hz. Methadone induced a concentration-dependent shift of the voltage dependency of both fast and slow inactivation towards more hyperpolarized potentials, and impaired recovery from fast and slow inactivation. The LA-insensitive mutants N406K and F1760A exhibited reduced tonic and use-dependent block by methadone, and docking predictions positioned methadone in a cavity that was delimited by the residue F1760. Dextromethadone and levomethadone induced discrete stereo-selective effects on Na(v)1.5 channels. CONCLUSIONS AND IMPLICATIONS Methadone interacted with the LA-binding site to inhibit Na(v)1.5 channels. Our data suggest that these channels are a hitherto unrecognized molecular component contributing to cardiac arrhythmias induced by methadone.
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Optimal approaches for balancing invasive species eradication and endangered species management. Science 2014; 344:1028-31. [DOI: 10.1126/science.1250763] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Chaperone-mediated native folding of a β-scorpion toxin in the periplasm of Escherichia coli. Biochim Biophys Acta Gen Subj 2013; 1840:10-5. [PMID: 23999087 PMCID: PMC3898981 DOI: 10.1016/j.bbagen.2013.08.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 08/15/2013] [Accepted: 08/26/2013] [Indexed: 11/18/2022]
Abstract
Background Animal neurotoxin peptides are valuable probes for investigating ion channel structure/function relationships and represent lead compounds for novel therapeutics and insecticides. However, misfolding and aggregation are common outcomes when toxins containing multiple disulfides are expressed in bacteria. Methods The β-scorpion peptide toxin Bj-xtrIT from Hottentotta judaica and four chaperone enzymes (DsbA, DsbC, SurA and FkpA) were co-secreted into the oxidizing environment of the Escherichia coli periplasm. Expressed Bj-xtrIT was purified and analyzed by HPLC and FPLC chromatography. Its thermostability was assessed using synchrotron radiation circular dichroism spectroscopy and its crystal structure was determined. Results Western blot analysis showed that robust expression was only achieved when cells co-expressed the chaperones. The purified samples were homogenous and monodisperse and the protein was thermostable. The crystal structure of the recombinant toxin confirmed that it adopts the native disulfide connectivity and fold. Conclusions The chaperones enabled correct folding of the four-disulfide-bridged Bj-xtrIT toxin. There was no apparent sub-population of misfolded Bj-xtrIT, which attests to the effectiveness of this expression method. General significance We report the first example of a disulfide-linked scorpion toxin natively folded during bacterial expression. This method eliminates downstream processing steps such as oxidative refolding or cleavage of a fusion-carrier and therefore enables efficient production of insecticidal Bj-xtrIT. Periplasmic chaperone activity may produce native folding of other extensively disulfide-reticulated proteins including animal neurotoxins. This work is therefore relevant to venomics and studies of a wide range of channels and receptors. Novel method for producing natively folded disulfide linked toxins Co-expression in periplasmic space with chaperones Crystal structure has the same structure/disulfide links as toxin from natural source. Synchrotron radiation circular dichroism spectroscopy shows thermal stability. Potential uses in studies of channel and receptor structure/function relationships
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Muscarinic receptor subtypes involved in urothelium-derived relaxatory effects in the inflamed rat urinary bladder. Auton Neurosci 2012; 170:5-11. [PMID: 22789737 DOI: 10.1016/j.autneu.2012.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 06/13/2012] [Accepted: 06/18/2012] [Indexed: 11/30/2022]
Abstract
Functional studies have shown altered cholinergic mechanisms in the inflamed bladder, which partly depend on muscarinic receptor-induced release of nitric oxide (NO). The current study aimed to characterize which muscarinic receptor subtypes that are involved in the regulation of the nitrergic effects in the bladder cholinergic response during cystitis. For this purpose, in vitro examinations of carbachol-evoked contractions of inflamed and normal bladder preparations were performed. The effects of antagonists with different selectivity for the receptor subtypes were assessed on intact and urothelium-denuded bladder preparations. In preparations from cyclophosphamide (CYP; in order to induce cystitis) pre-treated rats, the response to carbachol was about 75% of that of normal preparations. Removal of the urothelium or administration of a nitric oxide synthase inhibitor re-established the responses in the inflamed preparations. Administration of 4-diphenylacetoxy-N-methylpiperidine (4-DAMP) inhibited the carbachol-induced contractile responses of preparations from CYP pre-treated rats less potently than controls. Pirenzepine and p-fluoro-hexahydro-sila-diphenidol (pFHHSiD) affected the carbachol-induced contractile responses to similar extents in preparations of CYP pre-treated and control rats. However, the Schild slopes for the three antagonists were all significantly different from unity in the preparations from CYP pre-treated rats. Again, L-NNA or removal of the urothelium eliminated any difference compared to normal preparations. This study confirms that muscarinic receptor stimulation in the inflamed rat urinary bladder induces urothelial release of NO, which counteracts detrusor contraction.
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Experimental pathology. Nephrol Dial Transplant 2012. [DOI: 10.1093/ndt/gfs241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Acid-base/Na, K, Cl. Experimental and clinical. Clin Kidney J 2011. [DOI: 10.1093/ndtplus/4.s2.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd013605] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstracts: Left Ventricular electro-mechanics. Europace 2009. [DOI: 10.1093/europace/euq243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abstracts: Pacing results. Europace 2009. [DOI: 10.1093/europace/euq232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Moderated Posters: Cardiac resynchronisation therapy. Europace 2009. [DOI: 10.1093/europace/euq218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Multiple adenomatous polyps of the gallbladder presenting as carcinoma of the gallbladder. THE EUROPEAN JOURNAL OF SURGERY = ACTA CHIRURGICA 2001; 167:915-7. [PMID: 11841082 DOI: 10.1080/110241501753361604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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[Detection of human papillomavirus in cutaneous extragenital Bowen's disease in immunocompetent patients]. Ann Dermatol Venereol 2000; 127:40-5. [PMID: 10717561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
INTRODUCTION A specific link between human papillomavirus (HPV) types 16, 18, 31, and 33 and genital carcinomas and between HPV type 5 and cutaneous extragenital carcinomas in patients with epidermodysplasia verruciformis and renal transplant has been previously found. The aim of this prospective study was to detect HPV in cases of cutaneous extragenital Bowen's disease (BD) from non-immunosuppressed patients. PATIENTS AND METHODS Twelve cases of cutaneous extragenital BD or Bowen's carcinoma (BC), seen in the period 1994-1996 and confirmed by histologic examination, were included in the study. Tissue sections were studied by in situ hybridization with a mixture of HPV DNA probes and specific HPV DNA probes. In addition, study on fresh materiel from 1995 included: Southern blot hybridization with various usual HPV probes (6, 11, 16, 18, 31, 33, 35, 39, 42), polymerase chain reaction (PCR) with hybridization using consensus HPV probes and probes specific for HPV types 6, 11, 16, 18 and 33. In positive samples with conventional PCR, in situ PCR with probes specific for HPV types 6/11 and 16 was performed on tissue sections. RESULTS In situ hybridization was negative in all the cases. Southern blot hybridization was negative in our 9 studied cases. Three cases studied by consensus PCR were positive. PCR with specific HPV probes revealed positivity on two of these cases: HPV 6 in one, and HPV 16 in another. In situ PCR was positive with a mixed 6/11 HPV probe in the third positive consensus PCR case. DISCUSSION Our study revealed the presence of HPV in 3 out of 12 cases of cutaneous extragenital BD and BC. HPV type 16, found in BC of skull, was the most usually found type in the literature. HPV types 6/11, detected in 2 cases, were rarely found in cutaneous extragenital BD and BC and these results are in favor of the oncogenic effect of these virus types. In our study, in situ hybridization and Southern blot hybridization were negative in all the cases; HPV was only found in 3 cases by conventional PCR and in 1 case by in situ PCR. The low range of detection of HPV in cutaneous extragenital BD may be due to the used methods, to difficulties related to sampling and/or to a low number of copies of the HPV genoma.
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High-resolution measurement of the dielectronic recombination of fluorinelike selenium ions. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1996; 53:1413-1423. [PMID: 9913031 DOI: 10.1103/physreva.53.1413] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Dissociative recombination of cold HD+ at the Test Storage Ring. PHYSICAL REVIEW LETTERS 1993; 70:426-429. [PMID: 10054109 DOI: 10.1103/physrevlett.70.426] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Development of pseudobullous morphea and scleroderma-like illness during therapy with L-5-hydroxytryptophan and carbidopa. J Am Acad Dermatol 1991; 25:332-3. [PMID: 1918474 DOI: 10.1016/s0190-9622(08)80475-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Teaching checklist for home infusion therapy. Oncol Nurs Forum 1990; 17:923-6. [PMID: 2263519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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The induction of immunoblastic T cell sarcomas by virus-transformed prothymocytes. THE AMERICAN JOURNAL OF PATHOLOGY 1980; 101:265-82. [PMID: 6254363 PMCID: PMC1903601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The ontogeny of thymus-dependent lymphoid tumors induced by murine sarcoma-murine leukemia virus (MSV-MuLV) was investigated. Tumors that developed in spleens of infected mice 6 or more months after the injection of virus were diagnosed as immunoblastic T cell sarcomas. Cells derived from the tumors and established as a continuous cell line expressed the thymus leukemia (TL), brain-associated theta (BAT), and Qa2 cell surface antigens but lacked either the Ly 1 or Ly 2, 3 mature T cell differentiation antigens. In addition, the tumor cell expressed c type viral antigens, and had receptors for the lectin peanut agglutinin. The tumor cells were inert when tested for their capacity to respond in several functional T cell assays. Taken together, these data support the hypothesis that the primary target of malignant transformation by MSV-MuLV is a prothymocyte.
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Abstract
Mice injected intraperitoneally with 20 mg of ferritin twice weekly for more than 4 weeks developed proteinuria due to the deposition of ferritin-antiferritin antibody complexes in renal glomeruli. Deposits of ferritin, immunoglobulin G (IgG) and third complement component (C3) also accumulated in the perivascular, extracellular space of the choroid plexus as demonstrated by immunofluorescence and electron microscopy. The findings confirm previous observations on immune complex deposits in the choroid plexus in spontaneous autoimmune disease and persistent viral infections. The occurrence of similar deposits in the human choroid plexus and the possibility of an associated disturbance of the blood-spinal fluid barrier are discussed.
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Abstract
Incubation of neuroblastoma X glioma hybrid cells for 12-97 hr with methionine-enkephalin results in an increase in adenylate cyclase activity [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] that is mediated by the opiate receptor. The results show that cells become tolerant to, and dependent upon, enkephalin.
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A short lived polypeptide component of one of two discrete functional pools of hepatic nuclear alpha-amanitin resistant RNA polymerases. Biochem Biophys Res Commun 1974; 58:1030-8. [PMID: 4406947 DOI: 10.1016/s0006-291x(74)80247-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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