RESUMO
T cells autoreactive to the antigen-presenting molecule CD1a are common in human blood and skin, but the search for natural autoantigens has been confounded by background T cell responses to CD1 proteins and self lipids. After capturing CD1a-lipid complexes, we gently eluted ligands while preserving non-ligand-bound CD1a for testing lipids from tissues. CD1a released hundreds of ligands of two types. Inhibitory ligands were ubiquitous membrane lipids with polar head groups, whereas stimulatory compounds were apolar oils. We identified squalene and wax esters, which naturally accumulate in epidermis and sebum, as autoantigens presented by CD1a. The activation of T cells by skin oils suggested that headless mini-antigens nest within CD1a and displace non-antigenic resident lipids with large head groups. Oily autoantigens naturally coat the surface of the skin; thus, this points to a previously unknown mechanism of barrier immunity.
Assuntos
Antígenos CD1/imunologia , Autoantígenos/imunologia , Lipídeos/imunologia , Pele/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Apresentação de Antígeno , Antígenos CD1/genética , Autoantígenos/química , Autoantígenos/isolamento & purificação , Células HEK293 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipídeos/química , Lipídeos/isolamento & purificação , Ativação Linfocitária , Dados de Sequência Molecular , Ligação Proteica , Proteínas Recombinantes/genética , Relação Estrutura-AtividadeRESUMO
BACKGROUND: In 2020, the Council of State and Territorial Epidemiologists (CSTE) pertussis case definition was modified; the main change was classifying polymerase chain reaction (PCR)-positive cases as confirmed, regardless of cough duration. Pertussis data reported through Enhanced Pertussis Surveillance (EPS) in 7 sites and the National Notifiable Diseases Surveillance System (NNDSS) were used to evaluate the impact of the new case definition. METHODS: We compared the number of EPS cases with cough onset in 2020 to the number that would have been reported based on the prior (2014) CSTE case definition. To assess the impact of the change nationally, the proportion of EPS cases newly reportable under the 2020 CSTE case definition was applied to 2020 NNDSS data to estimate how many additional cases were captured nationally. RESULTS: Among 442 confirmed and probable cases reported to EPS states in 2020, 42 (9.5%) were newly reportable according to the 2020 case definition. Applying this proportion to the 6124 confirmed and probable cases reported nationally in 2020, we estimated that the new definition added 582 cases. Had the case definition not changed, reported cases in 2020 would have decreased by 70% from 2019; the observed decrease was 67%. CONCLUSIONS: Despite a substantial decrease in reported pertussis cases in the setting of coronavirus disease 2019 (COVID-19), our data show that the 2020 pertussis case definition change resulted in additional case reporting compared with the previous case definition, providing greater opportunities for public health interventions such as prophylaxis of close contacts.
Assuntos
Bordetella pertussis , Coqueluche , Coqueluche/epidemiologia , Coqueluche/diagnóstico , Coqueluche/prevenção & controle , Humanos , Estados Unidos/epidemiologia , Criança , Bordetella pertussis/genética , Bordetella pertussis/isolamento & purificação , Pré-Escolar , Lactente , Adolescente , Adulto , Adulto Jovem , Masculino , Vigilância da População , Feminino , Notificação de Doenças/estatística & dados numéricos , Reação em Cadeia da PolimeraseRESUMO
DENV infection outcomes depend on the host's variable expression of immune receptors and mediators, leading to either resolution or exacerbation. While the NS3 protein is known to induce robust immune responses, the specific impact of its protease region epitopes remains unclear. This study investigated the effect of recombinant NS3 protease region proteins from all four DENV serotypes on splenocyte activation in BALB/c mice (n = 5/group). Mice were immunized with each protein, and their splenocytes were subsequently stimulated with homologous antigens. We measured the expression of costimulatory molecules (CD28, CD80, CD86, CD152) by flow cytometry, along with IL-2 production, CD25 expression, and examined the antigen-specific activation of CD4 + and CD8 + T cells. Additionally, the expression of IL-1, IL-10, and TGF-ß1 in splenocytes from immunized animals was assessed. Apoptosis was evaluated using Annexin V/PI staining and DNA fragmentation analysis. Stimulation of splenocytes from immunized mice triggered apoptosis (phosphatidylserine exposure and caspase 3/7 activation) and increased costimulatory molecule expression, particularly CD152. Low IL-2 production and low CD25 expression, as well as sustained expression of the IL-10 gene. These results suggest that these molecules might be involved in mechanisms by which the NS3 protein contributes to viral persistence and disease pathogenesis.
Assuntos
Apoptose , Antígeno CTLA-4 , Vírus da Dengue , Camundongos Endogâmicos BALB C , Baço , Proteínas não Estruturais Virais , Animais , Camundongos , Baço/imunologia , Baço/virologia , Vírus da Dengue/imunologia , Vírus da Dengue/genética , Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Proteínas não Estruturais Virais/imunologia , Proteínas não Estruturais Virais/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genética , Imunização , Dengue/imunologia , Dengue/virologia , Citocinas/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologiaRESUMO
Adolescent parents and their offspring experience worse health outcomes throughout the life course. While over 90% of adolescent births occur in low- and middle-income countries, data from many such countries are lacking, particularly from fathers. This qualitative study conducted in Lima, Peru characterises the experience of adolescent fathers and identifies potential intervention targets. Interviews with young fathers and the mothers of their children were coded and analysed using thematic analysis and a grounded theory approach. Factors impacting their experience included family support, changes in their relationship with their partner, gender dynamics, and financial pressure. The study identified family and couple conflict, gendered expectations, and the father's personal development as potential intervention targets. Further research is needed to develop interventions that effectively engage adolescent fathers in low- and middle-income countries such as Peru, and support their transition to fatherhood.
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The binding activity of various trastuzumab biosimilars versus the branded trastuzumab towards the glycosylated extracellular domain of the human epidermal growth factor receptor 2 (HER2) target in the presence of pertuzumab was investigated. We employed size exclusion chromatography with tetra-detection methodology to simultaneously determine absolute molecular weight, concentration, molecular size, and intrinsic viscosity. All trastuzumab molecules in solution exhibit analogous behavior in their binary action towards HER2 regardless of the order of addition of trastuzumab/pertuzumab. This analogous behavior of all trastuzumab molecules, including biosimilars, highlights the robustness and consistency of their binding activity towards HER2. Furthermore, the addition of HER2 to a mixture of trastuzumab and pertuzumab leads to increased formation of high-order HER2 complexes, up to concentrations of one order of magnitude higher than in the case of sequential addition. The observed increase suggests a potential synergistic effect between these antibodies, which could enhance their therapeutic efficacy in HER2-positive cancers. These findings underscore the importance of understanding the complex interplay between therapeutic antibodies and their target antigens, providing valuable insights for the development of more effective treatment strategies.
Assuntos
Medicamentos Biossimilares , Neoplasias , Humanos , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Medicamentos Biossimilares/farmacologia , Medicamentos Biossimilares/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Cromatografia em GelRESUMO
The binding affinity of trastuzumab and pertuzumab to HER2 has been studied using both experimental and in silico methods. The experiments were conducted using the antibodies in their complete IgG form, as used in clinical therapy, and the extracellular domain of the HER2 protein in solution. This approach provides a precise, reproducible, and reliable view of the interaction between them in physicochemical conditions similar to those found in the tumoral environment. Dynamic light scattering and size exclusion chromatography coupled with tetra detection were utilized to characterize the protein complexes, measure their concentrations, and calculate the equilibrium-free binding energy, ΔGbind. In addition, PRODIGY, a QSAR-like model with excellent predictive ability, was employed to obtain in silico ΔGbind estimations. The results obtained indicate that pertuzumab exhibits a slightly higher binding affinity to HER2 than trastuzumab. The difference in binding affinity was explained based on the contribution of the different interfacial contact (IC) descriptors to the ΔGbind value estimated by the PRODIGY model. Furthermore, experiments revealed that the pertuzumab IgG antibody binds preferentially to two HER2 proteins, one per Fab fragment, while trastuzumab mainly forms a monovalent complex. This finding was interpreted based on a geometrical model that identified steric crowding in the trastuzumab-HER2 complex as compared with the pertuzumab-HER2 complex.
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Anticorpos Monoclonais , Receptor ErbB-2 , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Receptor ErbB-2/metabolismo , TrastuzumabRESUMO
Obsessive-compulsive disorder (OCD) is a debilitating psychiatric disorder. Worldwide, its prevalence is ~2% and its etiology is mostly unknown. Identifying biological factors contributing to OCD will elucidate underlying mechanisms and might contribute to improved treatment outcomes. Genomic studies of OCD are beginning to reveal long-sought risk loci, but >95% of the cases currently in analysis are of homogenous European ancestry. If not addressed, this Eurocentric bias will result in OCD genomic findings being more accurate for individuals of European ancestry than other ancestries, thereby contributing to health disparities in potential future applications of genomics. In this study protocol paper, we describe the Latin American Trans-ancestry INitiative for OCD genomics (LATINO, https://www.latinostudy.org). LATINO is a new network of investigators from across Latin America, the United States, and Canada who have begun to collect DNA and clinical data from 5000 richly phenotyped OCD cases of Latin American ancestry in a culturally sensitive and ethical manner. In this project, we will utilize trans-ancestry genomic analyses to accelerate the identification of OCD risk loci, fine-map putative causal variants, and improve the performance of polygenic risk scores in diverse populations. We will also capitalize on rich clinical data to examine the genetics of treatment response, biologically plausible OCD subtypes, and symptom dimensions. Additionally, LATINO will help elucidate the diversity of the clinical presentations of OCD across cultures through various trainings developed and offered in collaboration with Latin American investigators. We believe this study will advance the important goal of global mental health discovery and equity.
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CD1 activates T cells, but the function and size of the possible human T cell repertoires that recognize each of the CD1 antigen-presenting molecules remain unknown. Using an experimental system that bypasses major histocompatibility complex (MHC) restriction and the requirement for defined antigens, we show that polyclonal T cells responded at higher rates to cells expressing CD1a than to those expressing CD1b, CD1c or CD1d. Unlike the repertoire of invariant natural killer T (NKT) cells, the CD1a-autoreactive repertoire contained diverse T cell antigen receptors (TCRs). Functionally, many CD1a-autoreactive T cells homed to skin, where they produced interleukin 22 (IL-22) in response to CD1a on Langerhans cells. The strong and frequent responses among genetically diverse donors define CD1a-autoreactive cells as a normal part of the human T cell repertoire and CD1a as a target of the T(H)22 subset of helper T cells.
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Antígenos CD1/imunologia , Autoimunidade/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Pele/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Separação Celular , Quimiotaxia de Leucócito/imunologia , ELISPOT , Citometria de Fluxo , Humanos , Interleucinas/imunologia , Interleucinas/metabolismo , Células de Langerhans/imunologia , Células de Langerhans/metabolismo , Ativação Linfocitária/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/citologia , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/metabolismo , Interleucina 22RESUMO
Not available.
Assuntos
Poliomielite , Humanos , México/epidemiologia , Poliomielite/epidemiologia , Poliomielite/prevenção & controleRESUMO
OBJECTIVE: This study aimed to develop and validate a rapid, simple, accurate and precise analytical method for the quantification of L-AA in vitamin C serums. Moreover, the developed method was further applied to determine L-AA in eight different brands of vitamin C serums. A complementary study was also carried out to evaluate the stability of L-AA in the vitamin C serum samples after 15, 30, 45 and 60 days of storage at ambient temperature (15-35°C). METHODS: Ultra-high-performance liquid chromatography-tandem mass spectrometry was applied. RESULTS: Quantitative analyses were performed with a total chromatographic run time of 1.5 min by matrix-matched calibration, and the analytical curve was linear over the range of 1-1700 µg L-1 with a correlation coefficient of 0.9998. The limits of detection (LOD) and quantification (LOQ) were 0.3 and 1.0 µg L-1 , respectively. Intra- and inter-assay precisions, expressed in terms of relative standard deviation, ranged from 0.3% and 2.2%, respectively, and recoveries in concentration levels of 1 and 5 µg L-1 were 103.9% and 101.2%, respectively. The proposed analytical method was successfully applied to determine the L-AA content in eight commercial vitamin C serum samples. The stability of the target analyte in samples stored at ambient temperature (15-35°C) was evaluated throughout 60 days with a 15-day interval between analyses. At 0 days, L-AA content in samples ranged from 1.05 to 169.91 mg L-1 , which decreases over time. CONCLUSION: The proposed method could be powerful in routine analyses to ensure the quantification of L-AA in vitamin C serums since it proved to be a simple, reliable, fast, precise, accurate and sensitive analytical method.
OBJECTIF: Cette étude visait à développer et valider une méthode analytique rapide, simple, exacte et précise pour la quantification de l'acide L-ascorbique dans les sérums à la vitamine C. De plus, la méthode développée a été appliquée pour déterminer l'acide L-ascorbique dans huit différentes marques de sérums à la vitamine C. Une étude complémentaire a également été réalisée pour évaluer la stabilité de l'acide L-ascorbique dans les échantillons de sérum à la vitamine C après 15, 30, 45 et 60 jours de conservation à température ambiante (15 à 35 °C). MÉTHODES: La chromatographie en phase liquide à haute performance avec spectrométrie de masse en tandem a été employée. RÉSULTATS: Des analyses quantitatives ont été réalisées avec une durée totale d'exécution chromatographique de 1,5 minute par calibration matricielle appariée, et la courbe analytique était linéaire sur la plage de 1 à 1700 µg L-1 avec un coefficient de corrélation de 0,9998. La limite de détection (LD) et la limite de quantification (LQ) ont été déterminées à 0,3 et 1,0 µg L−1 , respectivement. Les précisions intra- et inter-essais, exprimées en termes d'écart-type relatif, étaient de 0,3 % et 2,2 %, respectivement, et les récupérations aux niveaux de concentration de 1 et 5 µg L-1 étaient de 103,9 % et 101,2 %, respectivement. La méthode analytique proposée a été employée avec succès pour déterminer la teneur en acide L-ascorbique de huit échantillons de sérum à la vitamine C commerciaux. La stabilité de l'analyte cible dans les échantillons conservés à température ambiante (15 à 35 °C) a été évaluée sur 60 jours avec un intervalle de 15 jours entre les analyses. À 0 jour, la teneur en acide L-ascorbique dans les échantillons était comprise entre 1,05 et 169,91 µg L-1 , ce qui diminue au fil du temps. CONCLUSION: La méthode proposée pourrait être puissante dans les analyses de routine pour assurer la quantification de l'acide L-ascorbique dans les sérums à la vitamine C puisqu'elle s'est avérée être une méthode analytique simple, fiable, rapide, précise, exacte et sensible.
Assuntos
Ácido Ascórbico , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Limite de DetecçãoRESUMO
The AS-48 bacteriocin is a potent antimicrobial polypeptide with enhanced stability due to its circular sequence of peptidic bonds. The mechanism of biological action is still not well understood in spite of both the elucidation of the molecular structure some years ago and several experiments performed that yielded valuable information about the AS-48 bacterial membrane poration activity. In this work, we present a computational study at an atomistic scale to analyze the membrane disruption mechanism. The process is based on the two-stage model: (1) peptide binding to the bilayer surface and (2) membrane poration due to the surface tension exerted by the peptide. Indeed, the induced membrane tension mechanism is able to explain stable formation of pores leading to membrane disruption. The atomistic detail obtained from the simulations allows one to envisage the contribution of the different amino acids during the poration process. Clustering of cationic residues and hydrophobic interactions between peptide and lipids seem to be essential ingredients in the process. GLU amino acids have shown to enhance the membrane disrupting ability of the bacteriocin. TRP24-TRP24 interactions make also an important contribution in the initial stages of the poration mechanism. The detailed atomistic information obtained from the simulations can serve to better understand bacteriocin structural characteristics to design more potent antimicrobial therapies.
Assuntos
Anti-Infecciosos , Bacteriocinas , Aminoácidos , Peptídeos Catiônicos Antimicrobianos/química , Bacteriocinas/farmacologia , Bicamadas Lipídicas/química , Simulação de Dinâmica MolecularRESUMO
BACKGROUND: Headache attributed to airplane travel is a rare form of headache that develops exclusively during airplane travel. It is characterized by occurring during takeoff, landing, or both, and improves spontaneously within 30 minutes after the ascent or descent of the airplane is completed. OBJECTIVES: Our objectives were to determine the prevalence of headache attributed to airplane travel among medical students who traveled by plane, the time of flight when it occurred, and the emotional state of passengers on new trips. METHODS: The study was prospective, cross-sectional, using a non-random sample of medical students who traveled by plane. In total, 155 passengers who traveled by plane on at least 3 flights, regardless of duration were interviewed. RESULTS: Headache during flight occurred 3 or more times in 7.5% (80/1070) of the trips and 14.2% (22/155) of the passengers, especially during takeoff or landing (17/22; 77.3%), having a stabbing character and lasting less than 30 minutes. The headache improved spontaneously at the end of the landing phase (17/22; 77.3%). When traveling again, 68.2% (15/22) of passengers traveled normally, despite previous painful experience. CONCLUSIONS: This study demonstrated that headache attributed to airplane travel is not as rare as previously thought, being predominant during takeoff or landing. In addition, despite the bothersome feeling, most passengers who experienced this headache traveled normally, despite previous painful experience.
Assuntos
Aeronaves , Cefaleia/epidemiologia , Cefaleia/etiologia , Estudantes de Medicina/estatística & dados numéricos , Doença Relacionada a Viagens , Adolescente , Adulto , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Estudos Prospectivos , Adulto JovemRESUMO
Pellets refer to solid biofuels for heating and power. The pellet's integrity is of great relevant to ensure safe and effective transportation and storage, and comfort to stakeholders. Several materials that are supportive, whether organic and inorganic, to pellets exist. However, no work in the literature is linking making hybrid non-wood pellets with addition of residual biomass from distillation of cellulosic bioethanol, and this requires further investigations. Figuring out how effective this challenging agro-industrial residue could be for reinforcing non-wood pellets is accordingly the scientific point of this study focusing on management of waste and valorization of biomass. The pilot-scale manufacturing of hybrid pellets consisted of systematically pressing sugarcane bagasse with the lignocellulosic reinforcement at the mass ratios of 3:1, 1:1, and 1:3 on an automatic pelletizer machine at 200 MPa and 125 °C. Elemental contents of C and H, durability, and energy density all increased significantly from 50.05 to 53.50%, 5.95 to 7.80%, 95.90 to 99.55%, and 28.20 to 31.20 MJ kg-1, respectively, with blending the starting material with the reinforcement at 1:3. Preliminary evidence of residual biomass from distillation of second-generation bioethanol capable of highly improving molecular flammable/combustible properties, mechanical stability, and fuel power of composite non-wood pellets exist.
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Biocombustíveis , Lignina/química , Biomassa , Carbono/química , Temperatura Alta , Hidrogênio/química , Oxigênio/química , Tamanho da Partícula , Pressão , Saccharum/químicaRESUMO
Soil waterlogging is a common problem in some agricultural areas, including regions under soybean (Glycine max) cultivation. In waterlogged soils, soil O2 depletion occurs due to aerobic microorganisms and plants, affecting the metabolic and physiological processes of plants after suffering anoxia in their root tissue. Another harmful factor in this situation is the exponential increase in the availability of iron (Fe) in the soil, which may result in absorption of excess Fe. The present study sought to evaluate the response mechanisms in soybean leaves 'Agroeste 3680' by physiological and biochemical analyses associating them with the development of pods in non-waterlogged and waterlogged soil, combined with one moderate and two toxic levels of Fe. Gas exchange was strongly affected by soil waterlogging. Excess Fe without soil waterlogging reduced photosynthetic pigments, and potentiated this reduction when associated with soil waterlogging. Starch and ureide accumulation in the first newly expanded trifoliate leaves proved to be response mechanisms induced by soil waterlogging and excess Fe, since plants cultivated under soil non-waterlogged soil at 25 mg dm-3 Fe showed lower contents when compared to stressed plants. Thus, starch and ureide accumulation could be considered efficient biomarkers of phytotoxicity caused by soil waterlogging and excess Fe in soybean plants. The reproductive development was abruptly interrupted by the imposition of stresses, leading to a loss of pod dry biomass, which was largely due to the substantial decrease in the net photosynthetic rate, as expressed by area (A), the blockage of carbohydrate transport to sink tissues and an increase of malondialdehyde (MDA). The negative effect on reproductive development was more pronounced under waterlogged soil.
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BACKGROUND: The incidence of pertussis in the United States has increased in recent years. While characteristics of severe pertussis infection have been described in infants, fewer data are available in older children and adults. In this analysis, we characterize pertussis infections in hospitalized patients of all ages. METHODS: Cases of pertussis with cough onset from 1 January 2011 through 31 December 2015 from 7 US Emerging Infections Program Network states were reviewed. Additional information on hospitalized patients was obtained through abstraction of the inpatient medical record. Descriptive and multivariable analyses were conducted to characterize severe pertussis infection and identify potential risk factors. RESULTS: Among 15942 cases of pertussis reported, 515 (3.2%) were hospitalized. Three hospitalized patients died. Infants aged <2 months accounted for 1.6% of all pertussis cases but 29.3% of hospitalizations. Infants aged 2-11 months and adults aged ≥65 years also had high rates of hospitalization. Infants aged <2 months whose mothers received acellular pertussis during the third trimester and children aged 2 months to 11 years who were up to date on pertussis-containing vaccines had a 43%-66% reduced risk of hospitalization. Among adolescents aged 12-20 years, 43.5% had a history of asthma, and among adults aged ≥65 years, 26.8% had a history of chronic obstructive pulmonary disease. CONCLUSIONS: Individuals at the extreme ends of life may be the most vulnerable to severe pertussis infections, though hospitalization was reported across all age groups. Continued monitoring of severe pertussis infections will be important to help guide prevention, control, and treatment options.
Assuntos
Coqueluche/epidemiologia , Coqueluche/patologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Gravidez , Fatores de Risco , Análise de Sobrevida , Estados Unidos/epidemiologia , Coqueluche/mortalidade , Adulto JovemRESUMO
Possible adverse effects of extremely low frequency magnetic fields (ELF-MF) are linked to a decrease of antioxidant defenses and the production of free radicals. The increase of free radicals affects the mitochondrial functionality inducing apoptosis, which affects the phosphorylation and generation of key ATP in fertilization. Myrciaria dubia, known as "camu camu," is a fruit with high levels of ascorbic acid, which exerts an important antioxidant function in the prevention of premature cell damage. In this study, the effect of Myrciaria dubia flour on oxidative damage produced by ELF-MF (610 µT) was evaluated by detecting the activity of endogenous mitochondrial oxidoreductase enzymes in a complete sperm cycle of mice. We found that the MF caused a significant (P < 0.05) decrease in sperm quality, whereas the groups supplied with Myrciaria dubia flour (50 and 75 mg/kg of body mass) in ELF-MF exposure showed a significant recovery (P < 0.05) in parameters of viability, percentage of plasma membrane integrity and mitochondrial activity, and index of epidymal sperm. This suggests that Myrciaria dubia flour would have an antioxidant activity that counteracts the damaging effects of ELF-MF in spermatogenesis and could be used as a natural ELF-MF protector. Bioelectromagnetics. 40:91-103, 2019. © 2019 Bioelectromagnetics Society.
Assuntos
Campos Eletromagnéticos , Infertilidade/prevenção & controle , Myrtaceae/química , Espermatozoides/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Ácido Ascórbico/metabolismo , Farinha , Radicais Livres/metabolismo , Frutas/química , Masculino , Camundongos , Oxirredutases/metabolismo , Plantas Medicinais , Espermatogênese/efeitos dos fármacosRESUMO
Protein AMPylation by Fic domain-containing proteins (Fic proteins) is an ancient and conserved post-translational modification of mostly unexplored significance. Here we characterize the Caenorhabditis elegans Fic protein FIC-1 in vitro and in vivo. FIC-1 is an AMPylase that localizes to the nuclear surface and modifies core histones H2 and H3 as well as heat shock protein 70 family members and translation elongation factors. The three-dimensional structure of FIC-1 is similar to that of its human ortholog, HYPE, with 38% sequence identity. We identify a link between FIC-1-mediated AMPylation and susceptibility to the pathogen Pseudomonas aeruginosa, establishing a connection between AMPylation and innate immunity in C. elegans.
Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Proteínas de Ligação a DNA/genética , Nucleotidiltransferases/genética , Elongação Traducional da Cadeia Peptídica , Proteínas Recombinantes/genética , Animais , Caenorhabditis elegans/química , Caenorhabditis elegans/microbiologia , Proteínas de Transporte/química , Proteínas de Transporte/genética , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Resposta ao Choque Térmico/genética , Histonas/genética , Histonas/metabolismo , Humanos , Imunidade Inata/genética , Proteínas de Membrana/química , Proteínas de Membrana/genética , Conformação Proteica , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidade , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismoRESUMO
The combination of hydrodynamic and electrophoretic experiments and computer simulations is a powerful approach to study the interaction between proteins. In this work, we present hydrodynamic and electrophoretic experiments in an aqueous solution along with molecular dynamics and hydrodynamic modeling to monitor and compute biophysical properties of the interactions between the extracellular domain of the HER2 protein (eHER2) and the monoclonal antibody trastuzumab (TZM). The importance of this system relies on the fact that the overexpression of HER2 protein is related with the poor prognosis breast cancers (HER2++ positives), while the TZM is a monoclonal antibody for the treatment of this cancer. We have found and characterized two different complexes between the TZM and eHER2 proteins (1:1 and 1:2 TZM:eHER2 complexes). The conformational features of these complexes regulate their hydrodynamic and electrostatic properties. Thus, the results indicate a high degree of molecular flexibility in the systems that ultimately leads to higher values of the intrinsic viscosity, as well as lower values of diffusion coefficient than those expected for simple globular proteins. A highly asymmetric charge distribution is detected for the monovalent complex (1:1 complex), which has strong implications in correlations between the experimental electrophoretic mobility and the modeled net charge. In order to understand the dynamics of these systems and the role of the specific domains involved, it is essential to find biophysical correlations between dynamics, macroscopic transport and electrostatic properties. The results should be of general interest for researchers working in this area.
Assuntos
Antineoplásicos Imunológicos/química , Simulação de Acoplamento Molecular , Receptor ErbB-2/química , Trastuzumab/química , Antineoplásicos Imunológicos/farmacologia , Sítios de Ligação , Humanos , Hidrodinâmica , Ligação Proteica , Receptor ErbB-2/metabolismo , Eletricidade Estática , Trastuzumab/farmacologiaRESUMO
In this work, two oligophenyleneimines type pentamers with terminal aldehydes, designated as DAFCHO (4,4'-((((((2,5-bis(octyloxy)-1,4-phenylene)bis(methanylylidene))bis(azanyl ylidene))bis(9H-fluorene-7,2-diyl))bis(azanylylidene))bis(methanylylidene))bis(2,5-bis(octyloxy) benzaldehyde)) and FDACHO (4,4'-((((((2,5-bis(octyloxy)-1,4-phenylene)bis(methanylylidene))bis (azanylylidene))bis(4,1-phenylene))bis(azanylylidene))bis(methanylylidene))bis(2,5-bis(octyloxy) benzaldehyde)) were synthesized by mechanochemistry method using 2,5-bis(octyloxy) terephtal aldehyde and 2,7-diaminofluorene or 1,4-phenylenediamine. All compounds were spectroscopically characterized using ¹H and 13C-NMR, FT-IR and mass spectrometry MALDITOF. The optical properties of the compounds were analyzed by UV-vis spectroscopy using different solvents. We observed that DAFCHO and FDACHO exhibit interesting photochromic properties when they are dissolved in chloroform and exposed to sunlight for 3, 5 and 10 min. The value of the energy band gap was calculated from the absorption spectra without irradiation Egap(optical). It was 2.50 eV for DAFCHO in chloroform solution, and it decreased to 2.34 eV when it is in films. For FDACHO, it was 2.41 eV in solution and 2.27 eV in film. HOMO (Highest Occupied Molecular Orbital), LUMO (Lowest Unoccupied Molecular Orbital) and Egap(electrochemical) values were obtained by electrochemical studies. The results indicate that the compounds can be considered as organic semiconductors since their values are 2.35 eV for DAFCHO and 2.06 eV for FDACHO. The structural and electronic properties of the compounds were corroborated with a DFT (Density Functional Theory) study.
Assuntos
Compostos de Anilina/química , Modelos Químicos , Modelos Moleculares , Polímeros/química , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , TermodinâmicaRESUMO
Seroepidemiologic studies, which measure serum antibody levels produced in response to infection and/or vaccination, can be valuable tools for gaining insight into population level dynamics of infectious diseases. However, because seroepidemiologic studies are expensive and logistically challenging, they are not routinely conducted for surveillance purposes. We have identified a novel venue, state fairgrounds, in which annual sera samples from a population may be rapidly collected with minimal recruitment expenses. We conducted a pilot pertussis seroepidemiologic study over the course of 3 days at the 2016 Minnesota State Fair to determine if this setting, which hosts nearly 2 million visitors over 12 days each year, is viable for facilitating larger seroepidemiologic studies. A total of 104 adults and children were enrolled to provide a finger stick blood sample for serologic testing and to take a written survey regarding recent cough illness and pertussis vaccination. The survey was used to distinguish between antibodies induced by vaccination and pertussis infection. Elevated antibodies suggestive of recent infection were found among two adults. The prevalence of undetectable antibodies, suggestive of susceptibility, was 72.3% (95% CI 59.6, 85.1%) among 7-17 year olds, 53.8% (95% CI 26.7, 80.9%) among 1-6 year olds, and 23.3% (95% CI 8.2, 38.5%) among adults. Our ability to rapidly enroll participants and collect satisfactory specimens suggests that seroepidemiologic studies with 1000-2000 participants could efficiently be completed over the 12-day course of the Minnesota State Fair. This setting raises the possibility of efficiently conducting annual population-based seroepidemiologic studies to supplement traditional public health surveillance in estimating disease prevalence, monitoring vaccine impact, and identifying at-risk groups.