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1.
Clin Pharmacol Ther ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38863207

RESUMEN

Methadone is a mu (µ) opioid receptor agonist used clinically in adults and children to manage opioid use disorder, neonatal abstinence syndrome, and acute and chronic pain. It is typically marketed as a racemic mixture of R- and S-enantiomers. R-methadone has 30-to 50-fold higher analgesic potency than S-methadone, and S-methadone has a greater adverse effect (prolongation) on the cardiac QTc interval. Methadone undergoes stereoselective metabolism. CYP2B6 is the primary enzyme responsible for catalyzing the metabolism of both enantiomers to the inactive metabolites, S- and R-2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (S- and R-EDDP). Genetic variation in the CYP2B6 gene has been investigated in the context of implications for methadone pharmacokinetics, dose, and clinical outcomes. Most CYP2B6 variants result in diminished or loss of CYP2B6 enzyme activity, which can lead to higher plasma methadone concentrations (affecting S- more than R-methadone). However, the data do not consistently indicate that CYP2B6-based metabolic variability has a clinically significant effect on methadone dose, efficacy, or QTc prolongation. Expert analysis of the published literature does not support a change from standard methadone prescribing based on CYP2B6 genotype (updates at www.cpicpgx.org).

2.
J Chem Ecol ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842636

RESUMEN

Animals that consume toxic diets provide models for understanding the molecular and physiological adaptations to ecological challenges. Garter snakes (Thamnophis) in western North America prey on Pacific newts (Taricha), which employ tetrodotoxin (TTX) as an antipredator defense. These snakes possess mutations in voltage-gated sodium channels (Nav), the molecular targets of TTX, that decrease the binding ability of TTX to sodium channels (target-site resistance). However, genetic variation at these loci that cannot explain all the phenotypic variation in TTX resistance in Thamnophis. We explored a separate means of resistance, toxin metabolism, to determine if TTX-resistant snakes either rapidly remove TTX or sequester TTX. We examined the metabolism and distribution of TTX in the body (toxicokinetics), to determine differences between TTX-resistant and TTX-sensitive snakes in the rates at which TTX is eliminated from organs and the whole body (using TTX half-life as our metric). We assayed TTX half-life in snakes from TTX-resistant and TTX-sensitive populations of three garter snake species with a coevolutionary history with newts (T. atratus, T. couchii, T. sirtalis), as well as two non-resistant "outgroup" species (T. elegans, Pituophis catenifer) that seldom (if ever) engage newts. We found TTX half-life varied across species, populations, and tissues. Interestingly, TTX half-life was shortest in T. elegans and P. catenifer compared to all other snakes. Furthermore, TTX-resistant populations of T. couchii and T. sirtalis eliminated TTX faster (shorter TTX half-life) than their TTX-sensitive counterparts, while populations of TTX-resistant and TTX-sensitive T. atratus showed no difference rates of TTX removal (same TTX half-life). The ability to rapidly eliminate TTX may have permitted increased prey consumption, which may have promoted the evolution of additional resistance mechanisms. Finally, snakes still retain substantial amounts of TTX, and we projected that snakes could be dangerous to their own predators days to weeks following the ingestion of a single newt. Thus, aspects of toxin metabolism may have been key in driving predator-prey relationships, and important in determining other ecological interactions.

3.
J Trauma Stress ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38853630

RESUMEN

Despite the established association between posttraumatic stress disorder (PTSD) and impulsivity, the literature is limited regarding impulsivity as a multifaceted construct. That is, the field's understanding of how PTSD symptoms may increase particular impulsive tendencies and behaviors is constrained by examining impulsivity solely as an umbrella term. The aim of the present study was to determine if there are differential associations between PTSD symptom severity and various components of impulsivity across multiple self-report measures. A sample of 215 undergraduate women (M age = 19.77 years, SD = 1.91, Range: 18-39 years) completed the PTSD Checklist for DSM-5 (PCL-5), Barratt Impulsiveness Scale (BIS-11), short version of the UPPS-P Impulsive Behavior Scale (SUPPS-P), and Delaying Gratification Inventory (DGI). Structural equation modeling was used to examine associations between PTSD symptoms and each measure's subscales. The findings included significant predictions from PTSD symptoms to the BIS-11 Attentional Impulsiveness subscale, ß = .23, SE = .07, 95% CI [.09, .37]; DGI Physical Pleasures, ß = -.24, SE = .07, 95% CI [-.38, -.11], and Achievement subscales, ß = -.19, SE = .08, 95% CI [-.34, -.04]; and the SUPPS-P Positive Urgency, ß = .22, SE = .08, 95% CI [.07, .37], and Negative Urgency subscales, ß = .32, SE = .07, 95% CI [.19, .46]. These results have implications for precision medicine approaches that emphasize targeting these specific facets of impulsivity, with likely downstream effects on health risk behaviors for emerging adult women.

4.
Vopr Virusol ; 69(2): 134-150, 2024 May 06.
Artículo en Ruso | MEDLINE | ID: mdl-38843020

RESUMEN

INTRODUCTION: SARS-CoV-2 infection causes immune disorders that create conditions for the reactivation of human herpesviruses (HHVs). However, the estimates of the HHVs effect on the course and outcome of COVID-19 are ambiguous. Аim - to study the possible relationship between the HHV reactivation and the adverse outcome of COVID-19. MATERIALS AND METHODS: Postmortem samples from the brain, liver, spleen, lymph nodes and lungs were obtained from 59 patients treated at the Moscow Infectious Diseases Hospital No.1 in 2021-2023. The group 1 comprised 39 patients with fatal COVID-19; group 2 (comparison group) included 20 patients not infected with SARS-CoV-2 who died from various somatic diseases. HHV DNA and SARS-CoV-2 RNA were determined by PCR. RESULTS: HHV DNA was found in autopsy samples from all patients. In group 1, EBV was most often detected in lymph nodes (94%), HHV-6 in liver (68%), CMV in lymph nodes (18%), HSV in brain (16%), VZV in lung and spleen (3% each). The detection rates of HHVs in both groups was similar. Important differences were found in viral load. In patients with COVID-19, the number of samples containing more than 1,000 copies of HHV DNA per 100,000 cells was 52.4%, in the comparison group - 16.6% (p < 0.002). An association has been established between the reactivation of HSV and HHV-6 and the severity of lung damage. Reactivation of EBV correlated with increased levels of liver enzymes. CONCLUSION: Reactivation of HHVs in patients with fatal COVID-19 was associated with severe lung and liver damages, which indicates a link between HHV reactivation and COVID-19 deaths.


Asunto(s)
Autopsia , COVID-19 , ADN Viral , Infecciones por Herpesviridae , Herpesviridae , SARS-CoV-2 , Humanos , COVID-19/virología , COVID-19/mortalidad , COVID-19/diagnóstico , COVID-19/patología , Femenino , Masculino , ADN Viral/genética , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Persona de Mediana Edad , Anciano , Herpesviridae/genética , Herpesviridae/aislamiento & purificación , Infecciones por Herpesviridae/virología , Infecciones por Herpesviridae/mortalidad , Adulto , Pulmón/virología , Pulmón/patología , Activación Viral , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/aislamiento & purificación , Moscú , Carga Viral , Ganglios Linfáticos/virología , Ganglios Linfáticos/patología , Anciano de 80 o más Años , Bazo/virología , Bazo/patología
5.
bioRxiv ; 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38826421

RESUMEN

Monogenic syndromes are associated with neurodevelopmental changes that result in cognitive impairments, neurobehavioral phenotypes including autism and attention deficit hyperactivity disorder (ADHD), and seizures. Limited studies and resources are available to make meaningful headway into the underlying molecular mechanisms that result in these symptoms. One such example is DeSanto-Shinawi Syndrome (DESSH), a rare disorder caused by pathogenic variants in the WAC gene. Individuals with DESSH syndrome exhibit a recognizable craniofacial gestalt, developmental delay/intellectual disability, neurobehavioral symptoms that include autism, ADHD, behavioral difficulties and seizures. However, no thorough studies from a vertebrate model exist to understand how these changes occur. To overcome this, we developed both murine and zebrafish Wac/wac deletion mutants and studied whether their phenotypes recapitulate those described in individuals with DESSH syndrome. We show that the two Wac models exhibit craniofacial and behavioral changes, reminiscent of abnormalities found in DESSH syndrome. In addition, each model revealed impacts to GABAergic neurons and further studies showed that the mouse mutants are susceptible to seizures, changes in brain volumes that are different between sexes and relevant behaviors. Finally, we uncovered transcriptional impacts of Wac loss of function that will pave the way for future molecular studies into DESSH. These studies begin to uncover some biological underpinnings of DESSH syndrome and elucidate the biology of Wac, with advantages in each model.

6.
bioRxiv ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38826344

RESUMEN

Cardiolipin (CL) is a mitochondria-specific phospholipid that forms heterotypic interactions with membrane-shaping proteins and regulates the dynamic remodeling and function of mitochondria. However, the precise mechanisms through which CL influences mitochondrial morphology are not well understood. In this study, employing molecular dynamics (MD) simulations, we observed CL localize near the membrane-binding sites of the mitochondrial fusion protein Optic Atrophy 1 (OPA1). To validate these findings experimentally, we developed a bromine-labeled CL probe to enhance cryoEM contrast and characterize the structure of OPA1 assemblies bound to the CL-brominated lipid bilayers. Our images provide direct evidence of interactions between CL and two conserved motifs within the paddle domain (PD) of OPA1, which control membrane-shaping mechanisms. We further observed a decrease in membrane remodeling activity for OPA1 in lipid compositions with increasing concentrations of monolyso-cardiolipin (MLCL). Suggesting that the partial replacement of CL by MLCL accumulation, as observed in Barth syndrome-associated mutations of the tafazzin phospholipid transacylase, compromises the stability of protein-membrane interactions. Our analyses provide insights into how biological membranes regulate the mechanisms governing mitochondrial homeostasis.

7.
Semin Neurol ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38876459

RESUMEN

There is an urgent need to expand access to treatment for persons with opioid use disorder (OUD). As neurologists may frequently encounter patients with chronic pain who have developed OUD, they are in a position to serve as advocates for treatment. Buprenorphine is the most scalable medication for OUD in the United States, yet expansion has plateaued in recent years despite growing treatment needs. Reluctance of providers to establish treatment with new patients, challenges with rural expansion, stigma related to buprenorphine-based care, and pharmacy pressures that incentivize low dispensing and inventories may have stalled expansion. This review introduces these challenges before outlining actionable and evidenced-based strategies that warrant investigation, including methods to improve patient access to care (remotely delivered care, mobile delivery programs, Bridge programs) and provider retention and confidence in prescribing (expert consults, Extension for Community Healthcare Outcomes, a telementoring model, hub-and-spoke services), as well as novel innovations (virtual reality, artificial intelligence, wearable technologies). Overall, fortifying existing delivery systems while developing new transformative models may be necessary to achieve more optimal levels of buprenorphine treatment expansion.

9.
Artículo en Inglés | MEDLINE | ID: mdl-38895868

RESUMEN

OBJECTIVE: Olfactory neuroblastoma is a rare sinonasal malignancy with comparatively positive prognosis and survival, but with a range of biological behaviors that can be difficult to prognosticate with current means of risk stratification. Neutrophil-to-lymphocyte ratio (NLR) has been found across a diverse range of malignancies to be associated with poorer outcomes. This paper aims to elucidate the relationship of NLR with olfactory neuroblastoma to assess its prognostic value in this setting. STUDY DESIGN: Retrospective chart review. SETTING: A single tertiary care academic hospital. METHODS: The study cohort included all patients treated for initial presentation of olfactory neuroblastoma from 2004 to 2020. NLR was calculated from preoperative labs, and each patient was evaluated for Kadish staging, Hyams grade, intraoperative positive margin, use of adjuvant therapy, posttreatment recurrence, and death. All statistical analysis was conducted using R and relationship between NLR and variables was assessed via binomial logistic regression. RESULTS: Forty-four patients were included, 24 were male. Average age 52.8, average length of follow-up was 9.6 years. Patients were grouped by low (Kadish A/B) and advanced (Kadish C/D) stage, n = 23 and n = 21, respectively, and low (Hyams I/II) and high (Hyams III/IV) risk, n = 15 and n = 11, respectively. Advanced Kadish stage was associated with elevated NLR, odds ratio 5.69 [2.30, 20.7], P = .001. No other variables were associated with elevated NLR including Hyams grade, margin status, recurrence, and mortality. CONCLUSION: Higher Kadish grade is associated with elevated NLR which may provide novel prognostic value to current risk-stratifying systems.

10.
Gait Posture ; 113: 139-144, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38897002

RESUMEN

BACKGROUND: Gait impairment is an early marker of Parkinson's disease (PD) and is frequently monitored to evaluate disease progression. Wearable sensors are increasingly being used to quantify gait in the real-world setting among people with PD (pwPD). Particularly, embedding wearables on devices or clothing that are worn daily may represent a useful strategy to improve compliance and regular monitoring of gait. RESEARCH QUESTION: The current investigation examined the validity of innovative smart glasses to measure gait among pwPD. METHODS: Participants wore the smart glasses and 6 APDM gait sensors simultaneously, while performing two walking tasks: the 3-meters Timed Up and Go test (TUG) and the 7-meters Stand and Walk (SAW) test. The following spatiotemporal gait parameters were calculated from the data collected using the two different devices: step time, step length, swing percentage, TUG duration, turn duration, and turn velocity. RESULTS: A total of 31 pwPD (mean age=68.6±8.5 years; 35.48 % female(N=11), mean Unified Parkinson's Disease Rating Scale (UPDRS) total score=32.1±14.7) participated in the study. Smart glasses achieved high validity in measuring step time (ICC=0.92, p=0.01) and TUG duration (ICC=0.96, p=0.03) compared to APDM sensors. On the other hand, the smart glasses did not achieve adequate validity when measuring step length, swing percentage, turn duration or turn velocity. SIGNIFICANCE: The current study suggests that smart glasses has the potential to measure TUG and step time in individuals living with PD. However, further research is needed to improve algorithms for sensors worn on the head.

11.
eNeuro ; 11(6)2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38834298

RESUMEN

In the rodent whisker system, active sensing and sensorimotor integration are mediated in part by the dynamic interactions between the motor cortex (M1) and somatosensory cortex (S1). However, understanding these dynamic interactions requires knowledge about the synapses and how specific neurons respond to their input. Here, we combined optogenetics, retrograde labeling, and electrophysiology to characterize the synaptic connections between M1 and layer 5 (L5) intratelencephalic (IT) and pyramidal tract (PT) neurons in S1 of mice (both sexes). We found that M1 synapses onto IT cells displayed modest short-term depression, whereas synapses onto PT neurons showed robust short-term facilitation. Despite M1 inputs to IT cells depressing, their slower kinetics resulted in summation and a response that increased during short trains. In contrast, summation was minimal in PT neurons due to the fast time course of their M1 responses. The functional consequences of this reduced summation, however, were outweighed by the strong facilitation at these M1 synapses, resulting in larger response amplitudes in PT neurons than IT cells during repetitive stimulation. To understand the impact of facilitating M1 inputs on PT output, we paired trains of inputs with single backpropagating action potentials, finding that repetitive M1 activation increased the probability of bursts in PT cells without impacting the time dependence of this coupling. Thus, there are two parallel but dynamically distinct systems of M1 synaptic excitation in L5 of S1, each defined by the short-term dynamics of its synapses, the class of postsynaptic neurons, and how the neurons respond to those inputs.


Asunto(s)
Corteza Motora , Optogenética , Corteza Somatosensorial , Animales , Corteza Somatosensorial/fisiología , Corteza Motora/fisiología , Masculino , Femenino , Vías Nerviosas/fisiología , Sinapsis/fisiología , Ratones , Neuronas/fisiología , Ratones Endogámicos C57BL , Vibrisas/fisiología , Tractos Piramidales/fisiología , Ratones Transgénicos , Potenciales Postsinápticos Excitadores/fisiología
12.
Cell Metab ; 36(6): 1394-1410.e12, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38838644

RESUMEN

A vexing problem in mitochondrial medicine is our limited capacity to evaluate the extent of brain disease in vivo. This limitation has hindered our understanding of the mechanisms that underlie the imaging phenotype in the brain of patients with mitochondrial diseases and our capacity to identify new biomarkers and therapeutic targets. Using comprehensive imaging, we analyzed the metabolic network that drives the brain structural and metabolic features of a mouse model of pyruvate dehydrogenase deficiency (PDHD). As the disease progressed in this animal, in vivo brain glucose uptake and glycolysis increased. Propionate served as a major anaplerotic substrate, predominantly metabolized by glial cells. A combination of propionate and a ketogenic diet extended lifespan, improved neuropathology, and ameliorated motor deficits in these animals. Together, intermediary metabolism is quite distinct in the PDHD brain-it plays a key role in the imaging phenotype, and it may uncover new treatments for this condition.


Asunto(s)
Encéfalo , Glucosa , Propionatos , Enfermedad por Deficiencia del Complejo Piruvato Deshidrogenasa , Animales , Enfermedad por Deficiencia del Complejo Piruvato Deshidrogenasa/metabolismo , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagen , Glucosa/metabolismo , Propionatos/metabolismo , Ratones , Dieta Cetogénica , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Masculino , Glucólisis
13.
Artículo en Inglés | MEDLINE | ID: mdl-38878020

RESUMEN

BACKGROUND: Biologic therapies inhibiting the IL-4 or IL-5 pathways are very effective in the treatment of asthma and other related conditions. However, the cytokines IL-4 and IL-5 also play a role in the generation of adaptive immune responses. Although these biologics do not cause overt immunosuppression, their effect in primary severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunization has not been studied completely. OBJECTIVE: Our aim was to evaluate the antibody and cellular immunity after SARS-CoV-2 mRNA vaccination in patients on biologics (PoBs). METHODS: Patients with severe asthma or atopic dermatitis who were taking benralizumab, dupilumab, or mepolizumab and had received the initial dose of the 2-dose adult SARS-CoV-2 mRNA vaccine were enrolled in a prospective, observational study. As our control group, we used a cohort of immunologically healthy subjects (with no significant immunosuppression) who were not taking biologics (NBs). We used a multiplexed immunoassay to measure antibody levels, neutralization assays to assess antibody function, and flow cytometry to quantitate Spike-specific lymphocytes. RESULTS: We analyzed blood from 57 patients in the PoB group and 46 control subjects from the NB group. The patients in the PoB group had lower levels of SARS-CoV-2 antibodies, pseudovirus neutralization, live virus neutralization, and frequencies of Spike-specific B and CD8 T cells at 6 months after vaccination. In subgroup analyses, patients with asthma who were taking biologics had significantly lower pseudovirus neutralization than did subjects with asthma who were not taking biologics. CONCLUSION: The patients in the PoB group had reduced SARS-CoV-2-specific antibody titers, neutralizing activity, and virus-specific B- and CD8 T-cell counts. These results have implications when considering development of a more individualized immunization strategy in patients who receive biologic medications blocking IL-4 or IL-5 pathways.

15.
Nat Commun ; 15(1): 4681, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824190

RESUMEN

The telomere sequence, TTAGGG, is conserved across all vertebrates and plays an essential role in suppressing the DNA damage response by binding a set of proteins termed shelterin. Changes in the telomere sequence impair shelterin binding, initiate a DNA damage response, and are toxic to cells. Here we identify a family with a variant in the telomere template sequence of telomerase, the enzyme responsible for telomere elongation, that led to a non-canonical telomere sequence. The variant is inherited across at least one generation and one family member reports no significant medical concerns despite ~9% of their telomeres converting to the novel sequence. The variant template disrupts telomerase repeat addition processivity and decreased the binding of the telomere-binding protein POT1. Despite these disruptions, the sequence is readily incorporated into cellular chromosomes. Incorporation of a variant sequence prevents POT1-mediated inhibition of telomerase suggesting that incorporation of a variant sequence may influence telomere addition. These findings demonstrate that telomeres can tolerate substantial degeneracy while remaining functional and provide insights as to how incorporation of a non-canonical telomere sequence might alter telomere length dynamics.


Asunto(s)
Linaje , Complejo Shelterina , Telomerasa , Proteínas de Unión a Telómeros , Telómero , Humanos , Telómero/metabolismo , Telómero/genética , Proteínas de Unión a Telómeros/metabolismo , Proteínas de Unión a Telómeros/genética , Complejo Shelterina/metabolismo , Telomerasa/genética , Telomerasa/metabolismo , Masculino , Femenino , Homeostasis del Telómero/genética , Secuencia de Bases , Adulto
16.
Pediatr Cardiol ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38836879

RESUMEN

Mental health (MH) is an important, yet understudied area of care for patients with congenital heart disease (CHD). Pediatric subspecialty fellows believe MH should be within their scope of practice, but few feel confident in their ability to appropriately screen, evaluate, manage, and make treatment referrals for youth with CHD and concurrent MH concerns. A 6-session, didactic-based curriculum was designed by an interprofessional team of experts. It was administered to pediatric cardiology fellows over 9 months during two academic years. Topics included the following: Introduction to MH and CHD, MH Screening and Clinic-Based Interventions, Psychopharmacology, Delirium, Trauma-Informed Care, and Adult CHD and Transitional Care. An investigator-designed survey was developed to assess fellow comfort with MH knowledge, screening, and treatment recommendation domains. Twenty-three fellows participated with 14 completing the pre-post survey (58% participation, 11/17 in year 1, 3/6 in year 2). Most participants were in their first year of training (9/14, 57%). Overall, fellow comfort with MH topics increased significantly (mean score 2.89 ± 0.46 vs. 3.4 ± 0.4, p = 0.0005), with improved comfort in the MH knowledge (p = 0.003) and treatment recommendation domains (p = 0.001). A didactic-based MH curriculum improves the comfort of pediatric cardiology fellows to address the MH concerns of their patients. The topics in this curriculum will continue to be refined over time and could be generalized to training programs, both nationally and across pediatric specialties, to improve MH care for high-risk populations.

17.
J Pediatr Psychol ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38872285

RESUMEN

OBJECTIVE: Culture and diversity-related training is critical to the development of competent pediatric psychologists. Evaluation of training efforts have been conducted at the program level, yet evaluation of trainee experiences in culture and diversity-related training remains unassessed. This trainee-led study was the first formal assessment of pediatric psychology trainee experiences of culture and diversity-related training and the impact of training on their own cultural humility. METHODS: Study overview and a survey link was distributed across 2 listservs associated with the American Psychological Association (Division 53, Division 54) and sent directly to directors of graduate, internship, and fellowship training programs with a request to share with trainees. Surveys assessing integration of cultural training and trainee cultural humility were completed. Trainees also provided qualitative feedback regarding their multicultural training and development. RESULTS: Pediatric psychology trainees (N = 90) reported inconsistent integration of culture and diversity topics into their training. Of the 34 training areas assessed, 10 were perceived as thoroughly integrated into formal training by at least half of the respondents. Trainees often sought independent cultural training outside of their programs, and no relationship was detected between perceived integration of cultural training and trainee cultural competence. DISCUSSION: Results indicate room for improvement regarding integration of cultural training and a need to better understand driving forces behind trainees independently seeking training outside of their formal training programs. Moreover, understanding the aspects of training that are most contributory to trainee development is needed given that no relationship between training and development emerged in the current study.

18.
Angew Chem Int Ed Engl ; : e202405634, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38742923

RESUMEN

In vivo electrochemistry in small brain regions or synapses requires nanoelectrodes with long straight tips for submicron scale measurements. Nanoelectrodes can be fabricated using a Nanoscribe two-photon printer, but annealed tips curl if they are long and thin. We propose a new pulling-force strategy to fabricate a straight carbon nanoneedle structure. A micron-width bridge is printed between two blocks. The annealed structure shrinks during pyrolysis, and the blocks create a pulling force to form a long, thin, and straight carbon bridge. Parameterization study and COMSOL modeling indicate changes in the block size, bridge size and length affect the pulling force and bridge shrinkage. Electrodes were printed on niobium wires, insulated with aluminum oxide, and the bridge cut with focused ion beam (FIB) to expose the nanoneedle tip. Annealed needle diameters ranged from 400 nm to 5.25 µm and length varied from 50.5 µm to 146 µm. The electrochemical properties are similar to glassy carbon, with good performance for dopamine detection with fast-scan cyclic voltammetry. Nanoelectrodes enable biological applications, such as dopamine detection in a specific Drosophila brain region. Long and thin nanoneedles are generally useful for other applications such as cellular sensing, drug delivery, or gas sensing.

20.
Lancet HIV ; 11(5): e285-e299, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38692824

RESUMEN

BACKGROUND: An effective HIV vaccine will most likely need to have potent immunogenicity and broad cross-subtype coverage. The aim of the HIV Vaccine Trials Network (HVTN) 124 was to evaluate safety and immunogenicity of a unique polyvalent DNA-protein HIV vaccine with matching envelope (Env) immunogens. METHODS: HVTN 124 was a randomised, phase 1, placebo-controlled, double-blind study, including participants who were HIV seronegative and aged 18-50 years at low risk for infection. The DNA vaccine comprised five plasmids: four copies expressing Env gp120 (clades A, B, C, and AE) and one gag p55 (clade C). The protein vaccine included four DNA vaccine-matched GLA-SE-adjuvanted recombinant gp120 proteins. Participants were enrolled across six clinical sites in the USA and were randomly assigned to placebo or one of two vaccine groups (ie, prime-boost or coadministration) in a 5:1 ratio in part A and a 7:1 ratio in part B. Vaccines were delivered via intramuscular needle injection. The primary outcomes were safety and tolerability, assessed via frequency, severity, and attributability of local and systemic reactogenicity and adverse events, laboratory safety measures, and early discontinuations. Part A evaluated safety. Part B evaluated safety and immunogenicity of two regimens: DNA prime (administered at months 0, 1, and 3) with protein boost (months 6 and 8), and DNA-protein coadministration (months 0, 1, 3, 6, and 8). All randomly assigned participants who received at least one dose were included in the safety analysis. The study is registered with ClinicalTrials.gov (NCT03409276) and is closed to new participants. FINDINGS: Between April 19, 2018 and Feb 13, 2019, 60 participants (12 in part A [five men and seven women] and 48 in part B [21 men and 27 women]) were enrolled. All 60 participants received at least one dose, and 14 did not complete follow-up (six of 21 in the prime-boost group and eight of 21 in the coadminstration group). 11 clinical adverse events deemed by investigators as study-related occurred in seven of 48 participants in part B (eight of 21 in the prime-boost group and three of 21 in the coadministration group). Local reactogenicity in the vaccine groups was common, but the frequency and severity of reactogenicity signs or symptoms did not differ between the prime-boost and coadministration groups (eg, 20 [95%] of 21 in the prime-boost group vs 21 [100%] of 21 in the coadministration group had either local pain or tenderness of any severity [p=1·00], and seven [33%] vs nine [43%] had either erythema or induration [p=0·97]), nor did laboratory safety measures. There were no delayed-type hypersensitivity reactions or vasculitis or any severe clinical adverse events related to vaccination. The most frequently reported systemic reactogenicity symptoms in the active vaccine groups were malaise or fatigue (five [50%] of ten in part A and 17 [81%] of 21 in the prime-boost group vs 15 [71%] of 21 in the coadministration group in part B), headache (five [50%] and 18 [86%] vs 12 [57%]), and myalgia (four [40%] and 13 [62%] vs ten [48%]), mostly of mild or moderate severity. INTERPRETATION: Both vaccine regimens were safe, warranting evaluation in larger trials. FUNDING: US National Institutes of Health and US National Institute of Allergy and Infectious Diseases.


Asunto(s)
Vacunas contra el SIDA , Anticuerpos Anti-VIH , Infecciones por VIH , VIH-1 , Vacunas de ADN , Humanos , Vacunas contra el SIDA/administración & dosificación , Vacunas contra el SIDA/inmunología , Vacunas contra el SIDA/efectos adversos , Adulto , Masculino , Femenino , Método Doble Ciego , Vacunas de ADN/administración & dosificación , Vacunas de ADN/inmunología , Vacunas de ADN/efectos adversos , Infecciones por VIH/prevención & control , Infecciones por VIH/inmunología , Persona de Mediana Edad , Adulto Joven , Anticuerpos Anti-VIH/sangre , Adolescente , VIH-1/inmunología , Estados Unidos , Inmunización Secundaria , Inmunogenicidad Vacunal , Proteína gp120 de Envoltorio del VIH/inmunología , Proteína gp120 de Envoltorio del VIH/genética , Anticuerpos Neutralizantes/sangre
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