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Severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) has developed substantial antigenic variability. As the majority of the population now has pre-existing immunity due to infection or vaccination, the use of experimentally generated animal immune sera can be valuable for measuring antigenic differences between virus variants. Here, we immunized Syrian hamsters by two successive infections with one of nine SARS-CoV-2 variants. Their sera were titrated against 16 SARS-CoV-2 variants, and the resulting titers were visualized using antigenic cartography. The antigenic map shows a condensed cluster containing all pre-Omicron variants (D614G, Alpha, Delta, Beta, Mu, and an engineered B.1+E484K variant) and considerably more diversity among a selected panel of Omicron subvariants (BA.1, BA.2, BA.4/BA.5, the BA.5 descendants BF.7 and BQ.1.18, the BA.2.75 descendant BN.1.3.1, the BA.2-derived recombinants XBB.2 and EG.5.1, and the BA.2.86 descendant JN.1). Some Omicron subvariants were as antigenically distinct from each other as the wildtype is from the Omicron BA.1 variant. Compared to titers measured in human sera, titers in hamster sera are of higher magnitude, show less fold change, and result in a more compact antigenic map topology. The results highlight the potential of sera from hamsters for the continued antigenic characterization of SARS-CoV-2.
Assuntos
Variação Antigênica , COVID-19 , Mesocricetus , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , SARS-CoV-2/imunologia , SARS-CoV-2/genética , COVID-19/imunologia , COVID-19/virologia , Cricetinae , Variação Antigênica/imunologia , Variação Antigênica/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Antígenos Virais/imunologia , Antígenos Virais/genética , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Humanos , Soros Imunes/imunologiaRESUMO
Influenza B virus primarily infects humans, causing seasonal epidemics globally. Two antigenic variants-Victoria-like and Yamagata-like-were detected in the 1980s, of which the molecular basis of emergence is still incompletely understood. Here, the antigenic properties of a unique collection of historical virus isolates, sampled from 1962 to 2000 and passaged exclusively in mammalian cells to preserve antigenic properties, were determined with the hemagglutination inhibition assay and an antigenic map was built to quantify and visualize the divergence of the lineages. The antigenic map revealed only three distinct antigenic clusters-Early, Victoria, and Yamagata-with relatively little antigenic diversity in each cluster until 2000. Viruses with Victoria-like antigenic properties emerged around 1972 and diversified subsequently into two genetic lineages. Viruses with Yamagata-like antigenic properties evolved from one lineage and became clearly antigenically distinct from the Victoria-like viruses around 1988. Recombinant mutant viruses were tested to show that insertions and deletions (indels), as observed frequently in influenza B virus hemagglutinin, had little effect on antigenic properties. In contrast, amino-acid substitutions at positions 148, 149, 150, and 203, adjacent to the hemagglutinin receptor binding site, determined the main antigenic differences between the Early, Victoria-like, and Yamagata-like viruses. Surprisingly, substitutions at two of the four positions reverted in recent viruses of the Victoria lineage, resulting in antigenic properties similar to viruses circulating â¼50 y earlier. These data shed light on the antigenic diversification of influenza viruses and suggest there may be limits to the antigenic evolution of influenza B virus.
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Influenza Humana , Animais , Variação Antigênica/genética , Sítios de Ligação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Hemaglutininas , Humanos , Vírus da Influenza B/genética , Mamíferos , FilogeniaRESUMO
We analyzed neutralizing antibodies in samples from ancestral + BA.1 and ancestral + BA.4/5 boosted individuals, collected around 5.5 months after booster. Titers of neutralizing antibodies generally decreased compared to a time point early after the bivalent booster immunization. This was more pronounced for individuals without infection history and for recently emerged Omicron variants.
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Vacinas contra COVID-19 , COVID-19 , Humanos , Anticorpos Amplamente Neutralizantes , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos AntiviraisRESUMO
Neutralizing antibodies are important correlates of protection against dengue. Yet, determinants of variation in neutralization across strains within the four dengue virus serotypes (DENV1-4) is imperfectly understood. Studies focus on structural DENV proteins, especially the envelope (E), the primary target of anti-DENV antibodies. Although changes in immune recognition (antigenicity) are often attributed to variation in epitope residues, viral processes influencing conformation and epitope accessibility also affect neutralizability, suggesting possible modulating roles of nonstructural proteins. We estimated effects of residue changes in all 10 DENV proteins on antigenic distances between 348 DENV collected from individuals living in Bangkok, Thailand (1994-2014). Antigenic distances were derived from response of each virus to a panel of twenty non-human primate antisera. Across 100 estimations, excluding 10% of virus pairs each time, 77 of 295 positions with residue variability in E consistently conferred antigenic effects; 52 were within ±3 sites of known binding sites of neutralizing human monoclonal antibodies, exceeding expectations from random assignments of effects to sites (p = 0.037). Effects were also identified for 16 sites on the stem/anchor of E which were only recently shown to become exposed under physiological conditions. For all proteins, except nonstructural protein 2A (NS2A), root-mean-squared-error (RMSE) in predicting distances between pairs held out in each estimation did not outperform sequences of equal length derived from all proteins or E, suggesting that antigenic signals present were likely through linkage with E. Adjusted for E, we identified 62/219 sites embedding the excess signals in NS2A. Concatenating these sites to E additionally explained 3.4% to 4.0% of observed variance in antigenic distances compared to E alone (50.5% to 50.8%); RMSE outperformed concatenating E with sites from any protein of the virus (ΔRMSE, 95%IQR: 0.01, 0.05). Our results support examining antigenic determinants beyond the DENV surface.
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Vírus da Dengue , Dengue , Aminoácidos , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos/genética , Tailândia , Proteínas do Envelope ViralRESUMO
Vaccines against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) have been highly efficient in protecting against Coronavirus Disease 2019 (COVID-19). However, the emergence of viral variants that are more transmissible and, in some cases, escape from neutralizing antibody responses has raised concerns. Here, we evaluated recombinant protein spike antigens derived from wild-type SARS-CoV-2 and from variants B.1.1.7, B.1.351, and P.1 for their immunogenicity and protective effect in vivo against challenge with wild-type SARS-CoV-2 in the mouse model. All proteins induced high neutralizing antibodies against the respective viruses but also induced high cross-neutralizing antibody responses. The decline in neutralizing titers between variants was moderate, with B.1.1.7-vaccinated animals having a maximum fold reduction of 4.8 against B.1.351 virus. P.1 induced the most cross-reactive antibody responses but was also the least immunogenic in terms of homologous neutralization titers. However, all antigens protected from challenge with wild-type SARS-CoV-2 in a mouse model.
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Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Chlorocebus aethiops , Reações Cruzadas , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Células VeroRESUMO
Medical evaluation for military applicants is an intricate process that requires an understanding of the terminology, standards, and guidelines. Allergy providers are often called to provide medical evaluations for patients who desire to join the military services. Without understanding the complexities and nuances of military medical evaluations, a provider may delay or not be able to assist their patient in obtaining the desired goal of joining the services. This article reviews the terminology of military medical evaluations and the guidelines and processes for these evaluations. We also focus our discussion on common allergic conditions that may be disqualifying for service and provide expert opinions of the subtleties of these conditions to provide the allergist with a practical approach to medical evaluations. Finally, we provide a list of resources that are accessible to any provider engaged in military medical evaluations for accessions.
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Hipersensibilidade , Militares , Humanos , Hipersensibilidade/diagnóstico , Guias de Prática Clínica como AssuntoRESUMO
In Fig. 2 of this Letter, the 'E' and 'G' clade labels were inadvertently reversed, and in Table 2 the genotype of DA27 was 'D1' instead of 'D5'. These have been corrected online.
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Hepatitis B virus (HBV) is a major cause of human hepatitis. There is considerable uncertainty about the timescale of its evolution and its association with humans. Here we present 12 full or partial ancient HBV genomes that are between approximately 0.8 and 4.5 thousand years old. The ancient sequences group either within or in a sister relationship with extant human or other ape HBV clades. Generally, the genome properties follow those of modern HBV. The root of the HBV tree is projected to between 8.6 and 20.9 thousand years ago, and we estimate a substitution rate of 8.04 × 10-6-1.51 × 10-5 nucleotide substitutions per site per year. In several cases, the geographical locations of the ancient genotypes do not match present-day distributions. Genotypes that today are typical of Africa and Asia, and a subgenotype from India, are shown to have an early Eurasian presence. The geographical and temporal patterns that we observe in ancient and modern HBV genotypes are compatible with well-documented human migrations during the Bronze and Iron Ages1,2. We provide evidence for the creation of HBV genotype A via recombination, and for a long-term association of modern HBV genotypes with humans, including the discovery of a human genotype that is now extinct. These data expose a complexity of HBV evolution that is not evident when considering modern sequences alone.
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Evolução Molecular , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B/virologia , Filogenia , África , Animais , Ásia , Europa (Continente) , Genótipo , Vírus da Hepatite B/classificação , História Antiga , História Medieval , Hominidae/virologia , Migração Humana/história , Humanos , Recombinação GenéticaRESUMO
Unanticipated trunk perturbation is commonly observed when anterior cruciate ligament (ACL) injuries occur during direction-changing manoeuvres. This study aimed to quantify the effect of mid-flight medial-lateral external trunk perturbation directions/locations on ACL loading variables during sidestep cuttings. Thirty-two recreational athletes performed sidestep cuttings under combinations of three perturbation directions (no-perturbation, ipsilateral-perturbation, and contralateral-perturbation relative to the cutting leg) and two perturbation locations (upper-trunk versus lower-trunk). The pushing perturbation was created by customised devices releasing a slam ball to contact participants near maximum jump height prior to cutting. Perturbation generally resulted in greater peak vertical ground reaction force and slower cutting velocity. Upper-trunk contralateral perturbation showed the greatest lateral trunk bending away from the travel direction, greatest peak knee flexion and abduction angles, and greatest peak internal knee adduction moments compared to other conditions. Such increased ACL loading variables were likely due to the increased lateral trunk bending and whole-body horizontal velocity away from the cutting direction caused by the contralateral perturbation act at the upper trunk. The findings may help understand the mechanisms of indirect contact ACL injuries and develop effective cutting techniques for ACL injury prevention.
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Lesões do Ligamento Cruzado Anterior , Tronco , Humanos , Tronco/fisiologia , Fenômenos Biomecânicos , Lesões do Ligamento Cruzado Anterior/fisiopatologia , Lesões do Ligamento Cruzado Anterior/prevenção & controle , Masculino , Adulto Jovem , Feminino , Ligamento Cruzado Anterior/fisiologia , Movimento/fisiologia , Joelho/fisiologia , AdultoRESUMO
We compared the serologic responses of 1 dose versus 2 doses of a variant vaccine (Moderna mRNA-1273 Beta/Omicron BA.1 bivalent vaccine) in adults. A 2-dose boosting regimen with a variant vaccine did not increase the magnitude or the durability of the serological responses compared to a single variant vaccine boost.
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Vacina de mRNA-1273 contra 2019-nCoV , Adulto , Humanos , Vacinas Combinadas , Protocolos Clínicos , RNA Mensageiro/genéticaRESUMO
In a randomized clinical trial, we compare early neutralizing antibody responses after boosting with bivalent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger RNA (mRNA) vaccines based on either BA.1 or BA.4/BA.5 Omicron spike protein combined with wild-type spike. Responses against SARS-CoV-2 variants exhibited the greatest reduction in titers against currently circulating Omicron subvariants for both bivalent vaccines.
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COVID-19 , Humanos , COVID-19/prevenção & controle , SARS-CoV-2/genética , Anticorpos Neutralizantes , Vacinas Combinadas , Anticorpos AntiviraisRESUMO
Connector 'hubs' are brain regions with links to multiple networks. These regions are hypothesized to play a critical role in brain function. While hubs are often identified based on group-average functional magnetic resonance imaging (fMRI) data, there is considerable inter-subject variation in the functional connectivity profiles of the brain, especially in association regions where hubs tend to be located. Here we investigated how group hubs are related to locations of inter-individual variability. To answer this question, we examined inter-individual variation at group-level hubs in both the Midnight Scan Club and Human Connectome Project datasets. The top group hubs defined based on the participation coefficient did not overlap strongly with the most prominent regions of inter-individual variation (termed 'variants' in prior work). These hubs have relatively strong similarity across participants and consistent cross-network profiles, similar to what was seen for many other areas of cortex. Consistency across participants was further improved when these hubs were allowed to shift slightly in local position. Thus, our results demonstrate that the top group hubs defined with the participation coefficient are generally consistent across people, suggesting they may represent conserved cross-network bridges. More caution is warranted with alternative hub measures, such as community density (which are based on spatial proximity to network borders) and intermediate hub regions which show higher correspondence to locations of individual variability.
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Conectoma , Rede Nervosa , Humanos , Vias Neurais , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Conectoma/métodosRESUMO
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
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Since late 2020, SARS-CoV-2 variants have regularly emerged with competitive and phenotypic differences from previously circulating strains, sometimes with the potential to escape from immunity produced by prior exposure and infection. The Early Detection group is one of the constituent groups of the US National Institutes of Health National Institute of Allergy and Infectious Diseases SARS-CoV-2 Assessment of Viral Evolution program. The group uses bioinformatic methods to monitor the emergence, spread, and potential phenotypic properties of emerging and circulating strains to identify the most relevant variants for experimental groups within the program to phenotypically characterize. Since April 2021, the group has prioritized variants monthly. Prioritization successes include rapidly identifying most major variants of SARS-CoV-2 and providing experimental groups within the National Institutes of Health program easy access to regularly updated information on the recent evolution and epidemiology of SARS-CoV-2 that can be used to guide phenotypic investigations.
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COVID-19 , SARS-CoV-2 , Estados Unidos/epidemiologia , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , National Institutes of Health (U.S.)RESUMO
Lipopolysaccharides (LPSs) are a hallmark virulence factor of Gram-negative bacteria. They are complex, structurally heterogeneous mixtures due to variations in number, type, and position of their simplest units: fatty acids and monosaccharides. Thus, LPS structural characterization by traditional mass spectrometry (MS) methods is challenging. Here, we describe the benefits of field asymmetric ion mobility spectrometry (FAIMS) for analysis of an intact R-type lipopolysaccharide complex mixture (lipooligosaccharide; LOS). Structural characterization was performed using Escherichia coli J5 (Rc mutant) LOS, a TLR4 agonist widely used in glycoconjugate vaccine research. FAIMS gas-phase fractionation improved the (S/N) ratio and number of detected LOS species. Additionally, FAIMS allowed the separation of overlapping isobars facilitating their tandem MS characterization and unequivocal structural assignments. In addition to FAIMS gas-phase fractionation benefits, extra sorting of the structurally related LOS molecules was further accomplished using Kendrick mass defect (KMD) plots. Notably, a custom KMD base unit of [Na-H] created a highly organized KMD plot that allowed identification of interesting and novel structural differences across the different LOS ion families, i.e., ions with different acylation degrees, oligosaccharides composition, and chemical modifications. Defining the composition of a single LOS ion by tandem MS along with the organized KMD plot structural network was sufficient to deduce the composition of 181 LOS species out of 321 species present in the mixture. The combination of FAIMS and KMD plots allowed in-depth characterization of the complex LOS mixture and uncovered a wealth of novel information about its structural variations.
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Espectrometria de Mobilidade Iônica , Lipopolissacarídeos , Humanos , Lipopolissacarídeos/química , Cefotaxima , Espectrometria de Massas em Tandem , Íons/química , Escherichia coliRESUMO
The production of costly public goods (as distinct from metabolic byproducts) has largely been understood through the realization that spatial structure can minimize losses to non-producing "cheaters" by allowing for the positive assortment of producers. In well-mixed systems, where positive assortment is not possible, the stable production of public goods has been proposed to depend on lineages that become indispensable as the sole producers of those goods while their neighbors lose production capacity through genome streamlining (the Black Queen Hypothesis). Here, we develop consumer-resource models motivated by nitrogen-fixing, siderophore-producing bacteria that consider the role of colimitation in shaping eco-evolutionary dynamics. Our models demonstrate that in well-mixed environments, single "public goods" can only be ecologically and evolutionarily stable if they are partially privatized (i.e., if producers reserve a portion of the product pool for private use). Colimitation introduces the possibility of subsidy: strains producing a fully public good can exclude non-producing strains so long as the producing strain derives sufficient benefit from the production of a second partially private good. We derive a lower bound for the degree of privatization necessary for production to be advantageous, which depends on external resource concentrations. Highly privatized, low-investment goods, in environments where the good is limiting, are especially likely to be stably produced. Coexistence emerges more rarely in our mechanistic model of the external environment than in past phenomenological approaches. Broadly, we show that the viability of production depends critically on the environmental context (i.e., external resource concentrations), with production of shared resources favored in environments where a partially-privatized resource is scarce.
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Evolução Biológica , EcologiaRESUMO
BACKGROUND: Sesame allergy has been characterized in the Middle East for some time. However, it has become more widely recognized as foods containing sesame and sesame seeds have become increasingly available in Australia, Europe, and North America. With the passage of the Food Allergy Safety, Treatment, Education, and Research Act in 2021, the United States will join other countries in identifying sesame as a major food allergen and require sesame to be labeled as a food allergen beginning in 2023. OBJECTIVE: To review the literature related to sesame allergy as an increasingly recognized food allergen around the world. DATA SOURCES: English-language articles retrieved by PubMed searches with relevance to sesame allergy. STUDY SELECTIONS: Articles were included using the search terms "sesame allergy" and "sesame seed allergy." RESULTS: A total of 69 relevant articles regarding sesame allergy, relating to its prevalence, clinical presentation, natural history, allergenic epitopes, diagnosis, and treatment, were selected. CONCLUSION: In recent decades, considerable gains have been made in determining prevalence and natural history of sesame allergy. With increased recognition and prevalence come the need for reliable methods of identification of sesame allergy and approaches for management.
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Hipersensibilidade Alimentar , Sesamum , Humanos , Alérgenos , Sesamum/efeitos adversos , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/terapia , Europa (Continente) , América do Norte/epidemiologiaRESUMO
BACKGROUND: There are no studies describing 12-week extended maintenance interval (EMI) immunotherapy (IT) efficacy in preventing anaphylaxis to imported fire ant (IFA) stings. OBJECTIVE: The purpose of this study was to determine the safety and efficacy of 12-week maintenance intervals in patients treated with IFA IT. METHODS: After a minimum of 3 months of conventional maintenance interval IT and verification of baseline efficacy, adults with IFA hypersensitivity were prospectively enrolled and extended their maintenance doses to 6-, 8-, and 12-week intervals. Efficacy was confirmed by means of an annual IFA sting challenge. RESULTS: A total of 25 patients initiated EMI. The severity of their initial systemic reactions was mild in 8 patients (32%), moderate in 10 patients (40%), and severe in 7 patients (28%). Maintenance IT duration at trial entry was less than 3 years in 18 patients (mean 11 months; range 3-28 months), 3 to 5 years in 4 patients (mean 46 months; range 36-57 months), and greater than 5 years in 5 patients (mean 111 months; range 67-197 months). The treatment cohort did not experience systemic reactions to extended interval injections, cluster refill injections, field stings, or sting challenges. CONCLUSION: This prospective longitudinal cohort study revealed that in adults 18 years old or older who have received at least 3 months of maintenance dose IFA-whole body extract IT with proven efficacy, extension to a 12-week EMI is a safe effective treatment option. The benefits of EMI include a reduced number of injections, clinic visits, and lapses in maintenance IT.
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Anafilaxia , Venenos de Formiga , Formigas , Mordeduras e Picadas de Insetos , Adulto , Animais , Humanos , Adolescente , Estudos Longitudinais , Estudos Prospectivos , Mordeduras e Picadas de Insetos/tratamento farmacológico , Imunoterapia , Venenos de Formiga/uso terapêuticoRESUMO
PURPOSE: Patient-reported outcome measures (PRO) are critical tools to developing an understanding of cancer patients' experience. This paper presents some of the lesser-understood implications of using patient-reported outcome measures in clinical research. METHODS: This study uses a combination of literature sources, real-world examples from supportive care studies, and statistical simulations to demonstrate the operating characteristics of patient-reported measures. RESULTS: It is demonstrated that care must be taken in the analysis of PROs as the assumptions of the most common mean-based approaches are often violated including linearity, normally distributed errors, interference with asymptotic convergence via boundary values, and more. Further, the implications of subjective discretization are shown to reduce the apparent statistical power of PRO-based studies. CONCLUSIONS: PRO-based studies must be designed conscientiously as each PRO item will demonstrate a varying degree of subjectivity in a given population. Sample sizes of randomized studies using PROs must be inflated to account for this. Analyses should consider using ordinal statistical models until such time as the assumptions of mean-based models can be verified.
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Neoplasias , Medidas de Resultados Relatados pelo Paciente , Humanos , Neoplasias/terapia , Modelos EstatísticosRESUMO
PURPOSE: This review was designed to compile the currently available evidence on the prophylactic use of gabapentin in the head and neck cancer patient population. METHODS: A systematic search was conducted of PubMed, Web of Science, and Google Scholar to identify articles related to the use of prophylactic gabapentin in patients undergoing head and neck cancer therapy. Candidate studies were screened for inclusion and a subsequent bias assessment was conducted by multiple reviewers. Meta-analysis was conducted in cases in which the studies used compatible outcome measures. RESULTS: Ten studies were identified that met the inclusion criteria and were assessed for bias. Among the four small studies that examined pain prevention, 2 were positive and 2 were inconclusive. Three of the four studies examiniRDng opioid use noted less need for opioids in the treatment arm. Meta-analysis of the pertinent studies showed no difference in feeding tube placement (RD = 0.64%, 95%CI: (- 25.8%, 27.1%), p = 0.962) but substantially less weight loss among those in the treatment arm (p = 0.047). CONCLUSION: Prophylactic gabapentin appears to be a promising treatment option for preventing pain, reducing opioids, and reducing weight loss in patients undergoing head and neck cancer therapy. However, the studies on the treatment to date are small and several have a substantial risk of bias.