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1.
J Med Syst ; 48(1): 70, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39073632

RESUMEN

This is the second in a series of studies assessing the usability and reliability of a novel voice-based delivery system of mental health screening assessments. The previous study demonstrated the reliability and patient preference of a voice-based format of the Patient Health Questionnaire 9 (PHQ 9) for measuring major depression compared to a traditional paper format. Through this study, we further examined the Amazon Alexa tool in the administration of the General Anxiety Disorder 7 (GAD 7). With a replicated methodology to the first study, 40 newly administered patients completed the GAD 7 in one format at their first session and the alternate format at their follow up. Results from the new in clinic population replicated the findings observed in the first PHQ 9 study: GAD 7 assessment scores for the Alexa and paper version showed a high degree of reliability (α = 0.77), patients showed higher overall positive attitudes for the voice-based GAD 7 format, and subscales for attractiveness, stimulation, and novelty were significantly higher for the voiced-based format. Results also demonstrated 42 (84%) of the 50 patients who completed the voice-based format responded as being willing to use the device from home. With new recommendations of universal screening of anxiety disorders for patients below the age of 65 and rapid changes in virtual mental healthcare, convenient screenings are more important than ever. We believe this novel clinical assessment tool has the potential to improve patient behavioral healthcare while mitigating the workload of healthcare professionals.


Asunto(s)
Trastornos de Ansiedad , Humanos , Femenino , Masculino , Reproducibilidad de los Resultados , Persona de Mediana Edad , Adulto , Trastornos de Ansiedad/diagnóstico , Voz , Encuestas y Cuestionarios , Psicometría , Anciano
2.
bioRxiv ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38293060

RESUMEN

Natural language-based generative artificial intelligence (AI) has become increasingly prevalent in scientific research. Intriguingly, capabilities of generative pre-trained transformer (GPT) language models beyond the scope of natural language tasks have recently been identified. Here we explored how GPT-4 might be able to perform rudimentary structural biology modeling. We prompted GPT-4 to model 3D structures for the 20 standard amino acids and an α-helical polypeptide chain, with the latter incorporating Wolfram mathematical computation. We also used GPT-4 to perform structural interaction analysis between nirmatrelvir and its target, the SARS-CoV-2 main protease. Geometric parameters of the generated structures typically approximated close to experimental references. However, modeling was sporadically error-prone and molecular complexity was not well tolerated. Interaction analysis further revealed the ability of GPT-4 to identify specific amino acid residues involved in ligand binding along with corresponding bond distances. Despite current limitations, we show the capacity of natural language generative AI to perform basic structural biology modeling and interaction analysis with atomic-scale accuracy.

3.
J Trauma Acute Care Surg ; 96(3): 364-370, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38011031

RESUMEN

BACKGROUND: Hemorrhage accounts for the most preventable deaths after trauma. Resuscitation is guided by studies that demonstrate improved outcomes in patients receiving whole blood or balanced administration of blood products. Platelets present a logistical challenge due to short shelf life and need for refrigeration. Platelet-derived extracellular vesicles (PEVs) are a possible platelet alternative. Platelet-derived extracellular vesicles are secreted from platelets, have hemostatic effects and mitigate inflammation and vascular injury, similar to platelets. This pilot study aimed to elucidate the therapeutic effects of PEVs in a rat model of uncontrolled hemorrhage. METHODS: Male rats were anesthetized and femoral vessels cannulated. Vital signs (MAP, HR, and RR) were monitored. Electrolytes, lactate and ABG were obtained at baseline, 1-hour and 3-hours post injury. Laparotomy was performed, 50% of the middle hepatic lobe excised and the abdomen packed with gauze. Rats received 2 mL PEVs or lactated Ringers (LR) over 6 minutes immediately after injury. Peritoneal blood loss was quantified using preweighed gauze at 5 minutes, 15 minutes, 30 minutes, 45 minutes, and 60 minutes. Laparotomy was closed 1-hour postinjury. Animals were monitored for 3 hours postinjury then euthanized. Generalized Linear Mixed Effects models were performed to assess effects of treatment and time on lactate and MAP. RESULTS: Twenty-one rats were included (11 LR, 10 PEV). Overall blood loss was between 6 mL and 10 mL and not significantly different between groups. There was a 36% mortality rate in the LR group and 0% mortality in the PEV group ( p = 0.03). The LR group had significantly higher lactates at 1 hour ( p = 0.025). At 15 minutes, 45 minutes, 60 minutes, and 180 minutes, the MAP of the PEV group was significantly higher than the LR group. CONCLUSION: Early studies are encouraging regarding the potential use of PEVs in uncontrolled hemorrhagic shock based on improved survival and hemodynamics.


Asunto(s)
Vesículas Extracelulares , Choque Hemorrágico , Humanos , Ratas , Masculino , Animales , Choque Hemorrágico/tratamiento farmacológico , Proyectos Piloto , Hemorragia/tratamiento farmacológico , Resucitación , Ácido Láctico , Soluciones Isotónicas/farmacología , Soluciones Isotónicas/uso terapéutico , Modelos Animales de Enfermedad
4.
Trends Biochem Sci ; 48(12): 1014-1018, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37833131

RESUMEN

Generative artificial intelligence (AI) is a burgeoning field with widespread applications, including in science. Here, we explore two paradigms that provide insight into the capabilities and limitations of Chat Generative Pre-trained Transformer (ChatGPT): its ability to (i) define a core biological concept (the Central Dogma of molecular biology); and (ii) interpret the genetic code.


Asunto(s)
Inteligencia Artificial , Código Genético , Biología Molecular
6.
J Med Syst ; 46(6): 38, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35536347

RESUMEN

Over the last two decades, metric-based instruments have garnered popularity in mental health. Self-administered surveys, such as the Patient Health Questionnaire 9 (PHQ 9), have been leveraged to inform treatment practice of Major Depressive Disorder (MDD). The aim of this study was to measure the reliability and usability of a novel voice-based delivery system of the PHQ 9 using Amazon Alexa within a patient population. Forty-one newly admitted patients to a behavioral medicine clinic completed the PHQ 9 at two separate time points (first appointment and one-month follow up). Patients were randomly assigned to a version (voice vs paper) completing the alternate format at the next appointment. Patients additionally completed a 26-item User Experience Questionnaire (UEQ) and open-ended questionnaire at each session. Assessments between PHQ 9 total scores for the Alexa and paper version showed a high degree of reliability (α = .86). Quantitative UEQ results showed significantly higher overall positive attitudes towards the Alexa format with higher subscale scores on attractiveness, stimulation, and novelty. Further qualitative responses supported these findings with 85.7% of participants indicating a willingness to use the device at home. With the benefit of user instruction in a clinical environment, the novel Alexa delivery system was shown to be consistent with the paper version giving evidence of reliability between the two formats. User experience assessments further showed a preference for the novel version over the traditional format. It is our hope that future studies may examine the efficacy of the Alexa format in improving the at-home clinical treatment of depression.


Asunto(s)
Trastorno Depresivo Mayor , Cuestionario de Salud del Paciente , Trastorno Depresivo Mayor/terapia , Humanos , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
7.
Wiley Interdiscip Rev RNA ; 13(5): e1718, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35199457

RESUMEN

Francis Crick advanced two distinct but interrelated fundamental principles of molecular biology: (1) the Sequence Hypothesis and (2) the Central Dogma. The Sequence Hypothesis defines biological information transfer as the residue-by-residue transfer of sequence information between nucleic acids and to proteins. This is commonly summarized as DNA âž” RNA âž” protein and is colloquially referred to as the Central Dogma. More specifically, however, the Central Dogma expounded by Crick included a critical restriction, stipulating that "once sequential information has passed into protein it cannot get out again." Under this definition, the Central Dogma has stood the test of time despite challenges. In principle, a violation of the Central Dogma could transpire through synthetic biology or by natural occurrence. To address these possibilities, we draw insights from existing modes of information transfer in protein synthesis and from synthetic Clustered Regularly-Interspaced Short Palindromic Repeats (CRISPR) gene-editing. We introduce a three-part evaluation scheme, which we apply to the CRISPR/Cas9 system and the more recent CRISPR prime editing system. Potential mechanisms by which engineered sequence editing systems might violate the Central Dogma are considered. We conclude that although information transfer in protein synthesis and CRISPR gene-editing remain within the bounds of the Central Dogma, the underlying mechanisms point toward an avenue of synthetic biology that could directly violate the Central Dogma. Finally, we speculate on some of the theoretical and practical implications of a protein-derived information transfer system. This article is categorized under: RNA Evolution and Genomics > Ribonomics RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications Translation > Mechanisms.


Asunto(s)
Edición Génica , ARN , ARN/genética
8.
J Agric Food Chem ; 68(13): 4036-4041, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32159957

RESUMEN

Waxy potato amylopectin has longer internal and external linear chains than rice or corn amylopectin that are capable of retrograding to a higher degree, but its molecular recrystallization is impeded by unprotonated phosphate groups. Here, we studied whether retrogradation and gel properties of waxy potato starch can be enhanced by lowering pH. The gel strength of waxy potato starch was strongly inversely correlated with pH, going from 10 to 4, and its magnitude was higher at pH values in which the ζ potential of the system was low. Waxy potato starch formed a strong aggregate gel driven by the formation of intermolecular double helices (G' drop25-95 °C ≈ 1358 Pa, melting ΔH = 9.5 J/g) when conditions that reduce electrostatic repulsion (pH 4, ζ = -1.7) are used, a phenomenon that was not observed in low-phosphorylated waxy cereal starches (i.e., waxy rice and corn).


Asunto(s)
Solanum tuberosum/química , Almidón/química , Rastreo Diferencial de Calorimetría , Conformación de Carbohidratos , Geles/química , Concentración de Iones de Hidrógeno , Temperatura
9.
EMBO J ; 39(6): e103777, 2020 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-32090359

RESUMEN

Research on non-coding RNA (ncRNA) is a rapidly expanding field. Providing an official gene symbol and name to ncRNA genes brings order to otherwise potential chaos as it allows unambiguous communication about each gene. The HUGO Gene Nomenclature Committee (HGNC, www.genenames.org) is the only group with the authority to approve symbols for human genes. The HGNC works with specialist advisors for different classes of ncRNA to ensure that ncRNA nomenclature is accurate and informative, where possible. Here, we review each major class of ncRNA that is currently annotated in the human genome and describe how each class is assigned a standardised nomenclature.


Asunto(s)
Genoma Humano/genética , ARN no Traducido/clasificación , Terminología como Asunto , Humanos , ARN no Traducido/genética
10.
Neurobiol Learn Mem ; 161: 51-56, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30862525

RESUMEN

The rodent odor span task (OST) uses an incrementing non-matching to sample procedure in which a series of odors is presented and selection of the session-novel odor is reinforced. An OST is frequently used to test the effects of neurobiological variables on memory capacity as the number of odors to remember increases during the course of the session. In this regard, one important finding has been that NMDA receptor antagonists selectively impair OST performance at doses that spare accuracy on control tasks. However, in many versions of the odor span task the number of stimuli to remember is confounded with the number of distractor odors presented to the rat on each trial. The present study compared the effects of the NMDA antagonist dizocilpine when the number of choices was held constant at two (one novel odor-S+ and one previously presented distractor odor-S-) and when the number of choice stimuli was permitted to increase up to 10 (one S+ and 9 S-). Dizocilpine impaired OST accuracy at doses that had no effect on a reference memory control task in both 2-choice and 10-choice conditions; however, the dose-response function was shifted to the left in the 10-choice tests. The impairments produced by dizocilpine were exacerbated as the memory load increased in both 2- and 10-choice conditions. These findings support the hypothesis that NMDA antagonism reduces the number of stimuli that rats can remember accurately, but the interaction between the effective DZP dose and the number of distractors shows that drug effects on OST performances may involve attentional factors in addition to memory capacity. The findings also demonstrate that variations in number of OST distractors can be used to alter sensitivity of the task.


Asunto(s)
Atención , Maleato de Dizocilpina/farmacología , Antagonistas de Aminoácidos Excitadores/farmacología , Memoria a Corto Plazo , Percepción Olfatoria , Desempeño Psicomotor , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Animales , Atención/efectos de los fármacos , Atención/fisiología , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Masculino , Memoria a Corto Plazo/efectos de los fármacos , Memoria a Corto Plazo/fisiología , Percepción Olfatoria/efectos de los fármacos , Percepción Olfatoria/fisiología , Desempeño Psicomotor/efectos de los fármacos , Desempeño Psicomotor/fisiología , Ratas , Ratas Sprague-Dawley
11.
Artículo en Inglés | MEDLINE | ID: mdl-29959195

RESUMEN

Protein synthesis involves a complex machinery comprising numerous proteins and RNAs joined by noncovalent interactions. Its function is to link long chains of amino acids into proteins with precise sequences as encoded by the genome. Regulation of protein synthesis, called translational control, occurs both at a global level and at specific messenger RNAs (mRNAs). To understand how translation is regulated, knowledge of the molecular structures and kinetic interactions of its components is needed. This review focuses on the targets of translational control and the mechanisms employed.


Asunto(s)
Regulación de la Expresión Génica , Genoma , Biosíntesis de Proteínas , Regiones no Traducidas 5' , Codón , Citoplasma/metabolismo , Cinética , Fosforilación , Conformación Proteica , Procesamiento Proteico-Postraduccional , Proteínas/metabolismo , ARN/metabolismo , ARN Mensajero/metabolismo , Ribosomas/metabolismo
12.
Artículo en Inglés | MEDLINE | ID: mdl-30082466

RESUMEN

Protein synthesis and its regulation are central to all known forms of life and impinge on biological arenas as varied as agriculture, biotechnology, and medicine. Otherwise known as translation and translational control, these processes have been investigated with increasing intensity since the middle of the 20th century, and in increasing depth with advances in molecular and cell biology. We review the origins of the field, focusing on the underlying concepts and early studies of the cellular machinery and mechanisms involved. We highlight key discoveries and events on a timeline, consider areas where current research has engendered new ideas, and conclude with some speculation on future directions for the field.


Asunto(s)
Biología Celular/historia , Regulación de la Expresión Génica , Biología Molecular/historia , Biosíntesis de Proteínas , Animales , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Oocitos/fisiología , Reticulocitos/fisiología , Erizos de Mar/fisiología
13.
Artículo en Inglés | MEDLINE | ID: mdl-29891561

RESUMEN

As obligate intracellular parasites, virus reproduction requires host cell functions. Despite variations in genome size and configuration, nucleic acid composition, and their repertoire of encoded functions, all viruses remain unconditionally dependent on the protein synthesis machinery resident within their cellular hosts to translate viral messenger RNAs (mRNAs). A complex signaling network responsive to physiological stress, including infection, regulates host translation factors and ribosome availability. Furthermore, access to the translation apparatus is patrolled by powerful host immune defenses programmed to restrict viral invaders. Here, we review the tactics and mechanisms used by viruses to appropriate control over host ribosomes, subvert host defenses, and dominate the infected cell translational landscape. These not only define aspects of infection biology paramount for virus reproduction, but continue to drive fundamental discoveries into how cellular protein synthesis is controlled in health and disease.


Asunto(s)
Regulación Viral de la Expresión Génica , Interacciones Huésped-Patógeno , Biosíntesis de Proteínas , Animales , Humanos , Virus de Plantas/metabolismo , Procesamiento Postranscripcional del ARN , Ribosomas/metabolismo , Estrés Fisiológico , Proteínas Virales/biosíntesis , Virosis/metabolismo , Replicación Viral
14.
J Exp Anal Behav ; 110(3): 366-379, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30431658

RESUMEN

Two experiments examined the emergence of generalized identity matching in rats using a successive discrimination procedure with olfactory stimuli. Trials consisted of the presentation of two odors separated by a 1-s interstimulus interval. Responses during the second odor presentation were reinforced only if the two odors were identical. In Experiment 1, rats were trained with two odors and then exposed to sessions that included unreinforced probe trials with novel odors. There was evidence of higher response rates on matching probe trials in some rats, but matching did not approach baseline levels. Additional training with four exemplars produced transfer to novel odors that was equivalent to baseline levels. Experiment 2 tested the possibility that detection of stimulus change, rather than generalized identity, was responsible for the transfer seen in Experiment 1. Thus, a masking odor was inserted during the 1-s interstimulus interval so that stimulus change occurred on all trials. Although response rates on probe trials were lower than baseline rates, above chance transfer to novel stimuli was still observed in four of the five animals tested. These findings support the hypothesis that transfer of matching to novel odors in this successive matching-to-sample paradigm is based on a generalized identity relation.


Asunto(s)
Condicionamiento Operante , Generalización Psicológica , Animales , Aprendizaje Discriminativo , Masculino , Odorantes , Estimulación Física , Ratas , Ratas Sprague-Dawley , Refuerzo en Psicología , Olfato
15.
Nat Rev Mol Cell Biol ; 19(12): 791-807, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30038383

RESUMEN

Advances in sequencing and high-throughput techniques have provided an unprecedented opportunity to interrogate human diseases on a genome-wide scale. The list of disease-causing mutations is expanding rapidly, and mutations affecting mRNA translation are no exception. Translation (protein synthesis) is one of the most complex processes in the cell. The orchestrated action of ribosomes, tRNAs and numerous translation factors decodes the information contained in mRNA into a polypeptide chain. The intricate nature of this process renders it susceptible to deregulation at multiple levels. In this Review, we summarize current evidence of translation deregulation in human diseases other than cancer. We discuss translation-related diseases on the basis of the molecular aberration that underpins their pathogenesis (including tRNA dysfunction, ribosomopathies, deregulation of the integrated stress response and deregulation of the mTOR pathway) and describe how deregulation of translation generates the phenotypic variability observed in these disorders.


Asunto(s)
Enfermedad/genética , Biosíntesis de Proteínas/genética , Biosíntesis de Proteínas/fisiología , Animales , Variación Biológica Poblacional/genética , Humanos , Factores de Iniciación de Péptidos/genética , ARN Mensajero/genética , ARN de Transferencia/genética , Ribosomas/genética , Estrés Fisiológico/genética , Serina-Treonina Quinasas TOR/genética
16.
Exp Clin Psychopharmacol ; 26(1): 6-17, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29389166

RESUMEN

The glutamate hypothesis proposes that N-Methyl-D-aspartate (NMDA) receptor hypofunction underlies cognitive and perhaps other schizophrenic symptoms. The present study used the odor span task to assess the effects of NMDA antagonists on remembering multiple stimuli in rodents. This task uses an incrementing nonmatching-to-sample procedure in which responses to a new olfactory stimulus are reinforced on each trial, whereas responses to previously presented stimuli are not. NMDA antagonists have been associated with memory impairments in a variety of animal models; however, there are inconsistencies across different NMDA antagonists and tasks used. The current study compared the acute effects of phencyclidine (PCP), ketamine (KET), and the novel NMDA antagonist methoxetamine (MXE) on responding in the odor span task and a simple discrimination control task. PCP and MXE impaired odor span accuracy at doses that did not impair simple discrimination in most rats; however, the effects of KET were less selective. Within-session analyses indicated that the effects of PCP and MXE depended on the number of stimuli to remember, that is, impairment only occurred when the memory load was relatively high. These effects of PCP and MXE were consistent with the hypothesis that NMDA antagonists may interfere with working memory, but the basis for less selective results with KET are unclear. (PsycINFO Database Record


Asunto(s)
Ciclohexanonas/farmacología , Ciclohexilaminas/farmacología , Ketamina/farmacología , Memoria a Corto Plazo/efectos de los fármacos , Odorantes/análisis , Fenciclidina/farmacología , Animales , Condicionamiento Operante/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/farmacología , Masculino , Ratas , Refuerzo en Psicología
17.
Behav Processes ; 155: 26-32, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28713029

RESUMEN

There is a growing body of research on matching- and non-matching-to-sample (MTS, NMTS) relations with rats using olfactory stimuli; however, the specific characteristics of this relational control are unclear. In the current study we examine MTS and NMTS in rats with an automated olfactometer using a successive (go, no-go) procedure. Ten rats were trained to either match- or non-match-to-sample with common scents (apple, cinnamon, etc.) as olfactory stimuli. After matching or non-matching training with four odorants, rats were tested for transfer twice with four new odorants on each test. Most rats trained on MTS showed immediate transfer to new stimuli, and most rats trained on NMTS showed full transfer by the second set of new odors. After meeting criterion on the second transfer test, the contingencies were reversed with four new odor stimuli such that subjects trained on matching were shifted to non-matching and vice versa. Following these reversed contingencies, the effects of the original training persisted for many trials with new odorants. These data extend previous studies on same-different concept formation in rats, showing strong generalization requiring few exemplars. The critical role of olfactory stimuli is discussed.


Asunto(s)
Odorantes , Desempeño Psicomotor/fisiología , Olfato/fisiología , Animales , Aprendizaje Discriminativo , Generalización Psicológica , Masculino , Ratas , Ratas Sprague-Dawley , Aprendizaje Inverso , Transferencia de Experiencia en Psicología
18.
Translation (Austin) ; 5(2): e1366294, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29034140

RESUMEN

Nonsense-mediated mRNA decay (NMD) couples protein synthesis to mRNA turnover. It eliminates defective transcripts and controls the abundance of certain normal mRNAs. Our study establishes a connection between NMD and the translation factor eIF5A (eukaryotic initiation factor 5A) in human cells. eIF5A modulates the synthesis of groups of proteins (the eIF5A regulon), and undergoes a distinctive two-step post-translational modification (hypusination) catalyzed by deoxyhypusine synthase and deoxyhypusine hydroxylase. We show that expression of NMD-susceptible constructs was increased by depletion of the major eIF5A isoform, eIF5A1. NMD was also attenuated when hypusination was inhibited by RNA interference with either of the two eIF5A modifying enzymes, or by treatment with the drugs ciclopirox or deferiprone which inhibit deoxyhypusine hydroxylase. Transcriptome analysis by RNA-Seq identified human genes whose expression is coordinately regulated by eIF5A1, its modifying enzymes, and the pivotal NMD factor, Upf1. Transcripts encoding components of the translation system were highly represented, including some encoding ribosomal proteins controlled by alternative splicing coupled to NMD (AS-NMD). Our findings extend and strengthen the association of eIF5A with NMD, previously inferred in yeast, and show that hypusination is important for this function of human eIF5A. In addition, they advance drug-mediated NMD suppression as a therapeutic opportunity for nonsense-associated diseases. We propose that regulation of mRNA stability contributes to eIF5A's role in selective gene expression.

19.
Neurobiol Learn Mem ; 145: 67-74, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28893667

RESUMEN

The odor span task is an incrementing non-matching-to-sample procedure designed to provide an analysis of working memory capacity in rodents. The procedure takes place in an arena apparatus and rats are exposed to a series of odor stimuli in the form of scented lids with the selection of new stimuli reinforced. This procedure makes it possible to study drug effects as a function of the number of stimuli to remember. In the present study, the non-selective positive allosteric GABAA receptor modulator flunitrazepam impaired odor span performance at doses that did not affect a control odor discrimination. In contrast, the alpha-1 selective positive GABAA receptor modulator zolpidem and the cholinergic receptor antagonist scopolamine only impaired odor span at doses that produced more global impairment, including decreased accuracy in the control discrimination and increased response omissions in the both the odor span and control discrimination procedures. Even though the effects of flunitrazepam were selective to odor span performance, they did not depend on the number of stimuli to remember-the same degree of impairment occurred regardless of the memory load. These findings suggest that flunitrazepam interfered selectively with conditional discrimination performance rather than working memory and tentatively suggest that flunitrazepam's selective effects in the odor span task relative to the control odor discrimination are mediated by one or more non-alpha1 GABAA receptor subtypes.


Asunto(s)
Amnesia/inducido químicamente , Flunitrazepam/administración & dosificación , Memoria a Corto Plazo/fisiología , Neurotransmisores/administración & dosificación , Piridinas/administración & dosificación , Escopolamina/administración & dosificación , Animales , Antagonistas Colinérgicos/administración & dosificación , Discriminación en Psicología/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Moduladores del GABA/administración & dosificación , Agonistas de Receptores de GABA-A/administración & dosificación , Masculino , Memoria a Corto Plazo/efectos de los fármacos , Odorantes , Percepción Olfatoria , Ratas Sprague-Dawley , Zolpidem
20.
PLoS One ; 11(5): e0154842, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27191165

RESUMEN

UNLABELLED: Antiretrovirals suppress HIV-1 production yet spare the sites of HIV-1 production, the HIV-1 DNA-harboring cells that evade immune detection and enable viral resistance on-drug and viral rebound off-drug. Therapeutic ablation of pathogenic cells markedly improves the outcome of many diseases. We extend this strategy to HIV-1 infection. Using drug-based lead discovery, we report the concentration threshold-dependent antiretroviral action of the medicinal chelator deferiprone and validate preclinical findings by a proof-of-concept double-blind trial. In isolate-infected primary cultures, supra-threshold concentrations during deferiprone monotherapy caused decline of HIV-1 RNA and HIV-1 DNA; did not allow viral breakthrough for up to 35 days on-drug, indicating resiliency against viral resistance; and prevented, for at least 87 days off-drug, viral rebound. Displaying a steep dose-effect curve, deferiprone produced infection-independent deficiency of hydroxylated hypusyl-eIF5A. However, unhydroxylated deoxyhypusyl-eIF5A accumulated particularly in HIV-infected cells; they preferentially underwent apoptotic DNA fragmentation. Since the threshold, ascertained at about 150 µM, is achievable in deferiprone-treated patients, we proceeded from cell culture directly to an exploratory trial. HIV-1 RNA was measured after 7 days on-drug and after 28 and 56 days off-drug. Subjects who attained supra-threshold concentrations in serum and completed the protocol of 17 oral doses, experienced a zidovudine-like decline of HIV-1 RNA on-drug that was maintained off-drug without statistically significant rebound for 8 weeks, over 670 times the drug's half-life and thus clearance from circulation. The uniform deferiprone threshold is in agreement with mapping of, and crystallographic 3D-data on, the active site of deoxyhypusyl hydroxylase (DOHH), the eIF5A-hydroxylating enzyme. We propose that deficiency of hypusine-containing eIF5A impedes the translation of mRNAs encoding proline cluster ('polyproline')-containing proteins, exemplified by Gag/p24, and facilitated by the excess of deoxyhypusine-containing eIF5A, releases the innate apoptotic defense of HIV-infected cells from viral blockade, thus depleting the cellular reservoir of HIV-1 DNA that drives breakthrough and rebound. TRIAL REGISTRATION: ClinicalTrial.gov NCT02191657.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Piridonas/uso terapéutico , Adolescente , Adulto , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/farmacología , Apoptosis/efectos de los fármacos , Línea Celular , Células Cultivadas , Deferiprona , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Descubrimiento de Drogas , Femenino , VIH-1/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Piridonas/administración & dosificación , Piridonas/efectos adversos , Piridonas/farmacología
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