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  1. Article ; Online: Enhanced T cell receptor specificity through framework engineering.

    Rosenberg, Aaron M / Ayres, Cory M / Medina-Cucurella, Angélica V / Whitehead, Timothy A / Baker, Brian M

    Frontiers in immunology

    2024  Volume 15, Page(s) 1345368

    Abstract: Development of T cell receptors (TCRs) as immunotherapeutics is hindered by inherent TCR cross ... new reactivities. Here we explored if TCR specificity could alternatively be tuned through framework ... by HLA-A2, we used deep mutational scanning to identify a framework mutation above the mobile CDR3β loop ...

    Abstract Development of T cell receptors (TCRs) as immunotherapeutics is hindered by inherent TCR cross-reactivity. Engineering more specific TCRs has proven challenging, as unlike antibodies, improving TCR affinity does not usually improve specificity. Although various protein design approaches have been explored to surmount this, mutations in TCR binding interfaces risk broadening specificity or introducing new reactivities. Here we explored if TCR specificity could alternatively be tuned through framework mutations distant from the interface. Studying the 868 TCR specific for the HIV SL9 epitope presented by HLA-A2, we used deep mutational scanning to identify a framework mutation above the mobile CDR3β loop. This glycine to proline mutation had no discernable impact on binding affinity or functional avidity towards the SL9 epitope but weakened recognition of SL9 escape variants and led to fewer responses in a SL9-derived positional scanning library. In contrast, an interfacial mutation near the tip of CDR3α that also did not impact affinity or functional avidity towards SL9 weakened specificity. Simulations indicated that the specificity-enhancing mutation functions by reducing the range of loop motions, limiting the ability of the TCR to adjust to different ligands. Although our results are likely to be TCR dependent, using framework engineering to control TCR loop motions may be a viable strategy for improving the specificity of TCR-based immunotherapies.
    MeSH term(s) T-Cell Antigen Receptor Specificity ; Receptors, Antigen, T-Cell ; Mutation ; Protein Binding ; Epitopes/metabolism
    Chemical Substances Receptors, Antigen, T-Cell ; Epitopes
    Language English
    Publishing date 2024-03-12
    Publishing country Switzerland
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2606827-8
    ISSN 1664-3224 ; 1664-3224
    ISSN (online) 1664-3224
    ISSN 1664-3224
    DOI 10.3389/fimmu.2024.1345368
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Hydroxychloroquine/ chloroquine as a treatment choice or prophylaxis for Covid-19 at the primary care level in developing countries: A Primum non Nocere dilemma.

    Medina, Marco T / Moncada, Sir Salvador

    Journal of the neurological sciences

    2020  Volume 415, Page(s) 116972

    Abstract: The Food and Drug Administration (FDA) warned against the use of Hydroxychloroquine or chloroquine for Covid-19 outside of a hospital or a clinical trial setting due to the risk of QT interval prolongation, ventricular tachycardia and the increased risk ... ...

    Abstract The Food and Drug Administration (FDA) warned against the use of Hydroxychloroquine or chloroquine for Covid-19 outside of a hospital or a clinical trial setting due to the risk of QT interval prolongation, ventricular tachycardia and the increased risk of these complications when combined with some antibiotics such as azithromycin. Several studies have reported no benefit of Hydroxychloroquine or chloroquine, when used alone or with a macrolide in COVID-19 hospitalized patients. Despite these warnings, in several developing countries the official guidelines for treatment of Covid-19 patients at the primary care level recommend Hydroxychloroquine and azithromycin, among other treatments, as the first-choice for mild symptomatic Covid-19 patients, asymptomatic contacts or for prophylaxis. In our opinion there is a primum non nocere dilemma during this Covid-19 pandemic. In order to solve this bioethical problem, we strongly recommend that a randomized controlled trial in a primary care setting be carried out as a matter of urgency in these areas of the world.
    MeSH term(s) Azithromycin ; Betacoronavirus ; COVID-19 ; Chloroquine ; Coronavirus Infections/drug therapy ; Developing Countries ; Humans ; Hydroxychloroquine ; Pandemics ; Pneumonia, Viral ; Primary Health Care ; SARS-CoV-2
    Chemical Substances Hydroxychloroquine (4QWG6N8QKH) ; Azithromycin (83905-01-5) ; Chloroquine (886U3H6UFF)
    Keywords covid19
    Language English
    Publishing date 2020-06-03
    Publishing country Netherlands
    Document type Editorial ; Comment
    ZDB-ID 80160-4
    ISSN 1878-5883 ; 0022-510X ; 0374-8642
    ISSN (online) 1878-5883
    ISSN 0022-510X ; 0374-8642
    DOI 10.1016/j.jns.2020.116972
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Tropical Neurology Education: A World Federation of Neurology outstanding priority.

    Medina, Marco T / Meshram, Chandrashekar / England, John / Shakir, Raad

    Journal of the neurological sciences

    2021  Volume 421, Page(s) 117281

    MeSH term(s) Educational Status ; Humans ; Neurology ; Societies, Medical
    Language English
    Publishing date 2021-02-10
    Publishing country Netherlands
    Document type Editorial
    ZDB-ID 80160-4
    ISSN 1878-5883 ; 0022-510X ; 0374-8642
    ISSN (online) 1878-5883
    ISSN 0022-510X ; 0374-8642
    DOI 10.1016/j.jns.2020.117281
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: In memoriam of Professor Theodore L. Munsat (1930-2013): his outstanding legacy with the WFN.

    Medina, Marco T

    Journal of the neurological sciences

    2014  Volume 339, Issue 1-2, Page(s) 1–2

    Abstract: The World Federation of Neurology (WFN) lost an outstanding leader on November 22, 2013 with the death of Professor Theodore Leon Munsat ("Ted"), in Waltham, Massachusetts, USA. Professor Munsat was Emeritus professor of Neurology at Tufts University ... ...

    Abstract The World Federation of Neurology (WFN) lost an outstanding leader on November 22, 2013 with the death of Professor Theodore Leon Munsat ("Ted"), in Waltham, Massachusetts, USA. Professor Munsat was Emeritus professor of Neurology at Tufts University School of Medicine and served the WFN in several capacities as trustee, chairman of the WFN Education and research committees, chairman of the WFN ALS Research group and founding director of the WFN Seminars in Clinical Neurology. He was president of the American Academy of Neurology (AAN), 1989-1991, chairman of the Continuing Educational Committee of the AAN and founding director of AAN's premier continuing medical education journal Continuum: Lifelong Learning in Neurology. He left an outstanding legacy with the WFN.
    MeSH term(s) History, 20th Century ; History, 21st Century ; Humans ; Leadership ; Neurology/history ; Physicians/history
    Language English
    Publishing date 2014-04-15
    Publishing country Netherlands
    Document type Biography ; Editorial ; Historical Article ; Portraits
    ZDB-ID 80160-4
    ISSN 1878-5883 ; 0022-510X ; 0374-8642
    ISSN (online) 1878-5883
    ISSN 0022-510X ; 0374-8642
    DOI 10.1016/j.jns.2014.01.031
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Hydroxychloroquine/ chloroquine as a treatment choice or prophylaxis for Covid-19 at the primary care level in developing countries

    Medina, Marco T. / Moncada, Sir Salvador

    Journal of the Neurological Sciences

    A Primum non Nocere dilemma

    2020  Volume 415, Page(s) 116972

    Keywords Neurology ; Clinical Neurology ; covid19
    Language English
    Publisher Elsevier BV
    Publishing country us
    Document type Article ; Online
    ZDB-ID 80160-4
    ISSN 1878-5883 ; 0022-510X ; 0374-8642
    ISSN (online) 1878-5883
    ISSN 0022-510X ; 0374-8642
    DOI 10.1016/j.jns.2020.116972
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: New spectrum of the neurologic consequences of Zika.

    Medina, Marco T / Medina-Montoya, Marco

    Journal of the neurological sciences

    2017  Volume 383, Page(s) 214–215

    Abstract: Zika virus infection represents a new neuropathological agent with association to a wide spectrum of neurological complications: a) Congenital Zika Syndrome by affecting the neural stem cells of the human fetal brain; b) Guillain-Barré Syndrome by an ... ...

    Abstract Zika virus infection represents a new neuropathological agent with association to a wide spectrum of neurological complications: a) Congenital Zika Syndrome by affecting the neural stem cells of the human fetal brain; b) Guillain-Barré Syndrome by an autoimmune response against peripheral myelin and/or axonal components or probable direct inflammatory reaction; c) Encephalitis/meningoencephalitis and myelitis by a direct viral inflammatory process on the central nervous system; d) Sensory neuropathy by infecting directly the peripheral neurons and causing substantial cell death and pathogenic transcriptional dysregulation; e) Acute Disseminated Encephalomyelitis and optic neuropathy; f) Seizures and Epilepsy and g) childhood arterial ischemic stroke by probable inflammatory reaction and endothelial injury.
    MeSH term(s) Humans ; Nervous System Diseases/etiology ; Nervous System Diseases/physiopathology ; Zika Virus Infection/complications ; Zika Virus Infection/physiopathology
    Language English
    Publishing date 2017-11-01
    Publishing country Netherlands
    Document type Editorial
    ZDB-ID 80160-4
    ISSN 1878-5883 ; 0022-510X ; 0374-8642
    ISSN (online) 1878-5883
    ISSN 0022-510X ; 0374-8642
    DOI 10.1016/j.jns.2017.10.046
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Hydroxychloroquine/ chloroquine as a treatment choice or prophylaxis for Covid-19 at the primary care level in developing countries: A Primum non Nocere dilemma

    Medina, Marco T / Moncada, Sir Salvador

    J Neurol Sci

    Abstract: The Food and Drug Administration (FDA) warned against the use of Hydroxychloroquine or chloroquine for Covid-19 outside of a hospital or a clinical trial setting due to the risk of QT interval prolongation, ventricular tachycardia and the increased risk ... ...

    Abstract The Food and Drug Administration (FDA) warned against the use of Hydroxychloroquine or chloroquine for Covid-19 outside of a hospital or a clinical trial setting due to the risk of QT interval prolongation, ventricular tachycardia and the increased risk of these complications when combined with some antibiotics such as azithromycin. Several studies have reported no benefit of Hydroxychloroquine or chloroquine, when used alone or with a macrolide in COVID-19 hospitalized patients. Despite these warnings, in several developing countries the official guidelines for treatment of Covid-19 patients at the primary care level recommend Hydroxychloroquine and azithromycin, among other treatments, as the first-choice for mild symptomatic Covid-19 patients, asymptomatic contacts or for prophylaxis. In our opinion there is a primum non nocere dilemma during this Covid-19 pandemic. In order to solve this bioethical problem, we strongly recommend that a randomized controlled trial in a primary care setting be carried out as a matter of urgency in these areas of the world.
    Keywords covid19
    Publisher WHO
    Document type Article
    Note WHO #Covidence: #506021
    Database COVID19

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  8. Article ; Online: Characterization of adult patients with Guillain-Barré syndrome during the arboviral infection outbreaks in Honduras.

    Sánchez, Odalis A / Portillo, Kendy M / Reyes-Garcia, Selvin Z / England, John D / Medina, Marco T

    Journal of the neurological sciences

    2021  Volume 427, Page(s) 117551

    Abstract: Arbovirus infections have been associated with a wide spectrum of neurological manifestations. Among these, Guillain-Barré syndrome (GBS) is one of the most common. This study describes the characteristics of GBS associated with arbovirus infections ... ...

    Abstract Arbovirus infections have been associated with a wide spectrum of neurological manifestations. Among these, Guillain-Barré syndrome (GBS) is one of the most common. This study describes the characteristics of GBS associated with arbovirus infections during the outbreak which occurred in Honduras from January 2016 to February 2019. This was an observational retrospective study of adult patients who were diagnosed with GBS during that time. The diagnosis of GBS was based upon the criteria first published by Asbury, et al. and subsequently revised as the Brighton Criteria. A total of 91 patients with GBS constituted the study population. RT-PCR tests for ZIKV, CHIKV, and DENV arboviruses were performed in 47 (52%) of the patients. Of the tested population, 8/47 were positive for one of the arboviruses (5/8 for ZIKV, 3/8 for CHIKV; 0/8 for DENV). The clinical profile of the eight cases with GBS and arboviral infection did not differ significantly from the GBS patients who tested negative for ZIKV and CHIKV. In the cases with GBS and ZIKV, a parainfectious onset of the disease was suggested. Although not a strikingly large number of patients with GBS and arbovirus infection were seen, the close temporal relationship in these eight cases suggests an arbovirus (ZIKV and CHIKV) etiology.
    MeSH term(s) Adult ; Dengue/epidemiology ; Disease Outbreaks ; Guillain-Barre Syndrome/epidemiology ; Honduras/epidemiology ; Humans ; Retrospective Studies ; Zika Virus ; Zika Virus Infection/complications ; Zika Virus Infection/diagnosis ; Zika Virus Infection/epidemiology
    Language English
    Publishing date 2021-06-21
    Publishing country Netherlands
    Document type Journal Article ; Observational Study
    ZDB-ID 80160-4
    ISSN 1878-5883 ; 0022-510X ; 0374-8642
    ISSN (online) 1878-5883
    ISSN 0022-510X ; 0374-8642
    DOI 10.1016/j.jns.2021.117551
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: The Pan-American Federation of Neurological Societies (PAFNS): A New Regional Organization.

    Medina, Marco T / Román, Gustavo C

    Journal of the neurological sciences

    2016  Volume 366, Page(s) 195–196

    Abstract: The Pan-American Federation of Neurological Societies (PAFNS) was created on 15 November 2011 during the 20th World Congress of Neurology in Marrakech by virtue of the "Declaration of Morocco" signed by the WFN Latin American delegates and ratified on 5 ... ...

    Abstract The Pan-American Federation of Neurological Societies (PAFNS) was created on 15 November 2011 during the 20th World Congress of Neurology in Marrakech by virtue of the "Declaration of Morocco" signed by the WFN Latin American delegates and ratified on 5 March 2012 by delegates attending the 13th Pan-American Congress of Neurology in La Paz, Bolivia. On 20 March 2013 delegates attending the 65th Annual Meeting of the American Academy of Neurology in San Diego, California, USA, gave formal approval to the PAFNS Constitution. The neurological societies from the following countries have approved and signed the constitution as founding members and active ordinary members: Argentina, Brazil, Bolivia, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, Puerto Rico, Uruguay, and Venezuela. The Ibero-American Stroke Society (SIECV), the Commission on Latin American Affairs of the International League Against Epilepsy (ILAE) and the World Sleep Society have requested the status of Associate Members. The WFN and the American Academy of Neurology provided seed grants for the creation of the Pan-American Federation of Neurological Societies. PAFNS represents a major step for the improvement of regional neurological care, education and research.
    MeSH term(s) Humans ; Latin America ; Neurology ; Societies, Medical
    Language English
    Publishing date 2016-07-15
    Publishing country Netherlands
    Document type Editorial
    ZDB-ID 80160-4
    ISSN 1878-5883 ; 0022-510X ; 0374-8642
    ISSN (online) 1878-5883
    ISSN 0022-510X ; 0374-8642
    DOI 10.1016/j.jns.2016.03.052
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Light-stimulated dephosphorylation of the BiP-like protein, SmicHSP75 (SBiP1) from Symbiodinium microadriaticum is inhibited by elevated but not low temperature and suggests regulation of the chaperone function.

    Castillo-Medina, Raúl Eduardo / Islas-Flores, Tania / Villanueva, Marco

    Acta biochimica Polonica

    2022  Volume 69, Issue 1, Page(s) 155–164

    Abstract: Specific phosphorylation/dephosphorylation processes are fundamental for the transduction of external stimuli into physiological responses. A few of these processes appear to be modulated by light in cultured Symbiodinium microadriaticum since the BiP- ... ...

    Abstract Specific phosphorylation/dephosphorylation processes are fundamental for the transduction of external stimuli into physiological responses. A few of these processes appear to be modulated by light in cultured Symbiodinium microadriaticum since the BiP-like protein SmicHSP75 undergoes threonine dephosphorylation upon light stimuli. Several isoforms of the protein are encoded in the S. microadriaticum genome and thus, we identified and heterologously expressed a specific sequence corresponding to the previously identified SmicHSP75 isoform to obtain a highly specific antibody. We then determined by western blot analysis, that the detected light-stimulated changes in SmicHSP75 threonine phosphorylation were not due to changes in the protein expression and explored further the effect of lower than normal and higher stressful temperature, on the phosphorylation levels of the protein. Upon long-term (12 h) exposure of the cells to the low temperature of 21ºC under darkness, the protein was found significantly phosphorylated; however, light exposure for 30 min caused a dephosphorylation effect like the 26ºC control treatment. On the other hand, in cells exposed to 32ºC for 12 h under darkness, the highly Thr-phosphorylated SmicHSP75 was converted to a low-level phosphorylated protein. Likewise, short term (30 min) exposure to 32ºC under dark conditions caused dephosphorylation of the protein, similar to what was observed upon long-term exposure to 32ºC and upon light stimulation of cells under the normal temperature of 26ºC. These data suggested activation/inactivation of the chaperone function of SmicHSP75 by regulation of its Thr phosphorylation levels under heat stress conditions in Symbiodinium microadriaticum, independent of changes in protein expression.
    MeSH term(s) Animals ; Cold Temperature ; Darkness ; Dinoflagellida/metabolism ; Heat-Shock Proteins/metabolism ; Hot Temperature ; Light ; Molecular Chaperones/metabolism ; Phosphorylation ; Temperature ; Threonine/metabolism
    Chemical Substances Heat-Shock Proteins ; Molecular Chaperones ; Threonine (2ZD004190S)
    Language English
    Publishing date 2022-02-11
    Publishing country Poland
    Document type Journal Article
    ZDB-ID 595762-x
    ISSN 1734-154X ; 0001-527X
    ISSN (online) 1734-154X
    ISSN 0001-527X
    DOI 10.18388/abp.2020_5788
    Database MEDical Literature Analysis and Retrieval System OnLINE

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