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1.
Proc Natl Acad Sci U S A ; 121(23): e2319499121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38814867

RESUMEN

Plants and animals detect biomolecules termed microbe-associated molecular patterns (MAMPs) and induce immunity. Agricultural production is severely impacted by pathogens which can be controlled by transferring immune receptors. However, most studies use a single MAMP epitope and the impact of diverse multicopy MAMPs on immune induction is unknown. Here, we characterized the epitope landscape from five proteinaceous MAMPs across 4,228 plant-associated bacterial genomes. Despite the diversity sampled, natural variation was constrained and experimentally testable. Immune perception in both Arabidopsis and tomato depended on both epitope sequence and copy number variation. For example, Elongation Factor Tu is predominantly single copy, and 92% of its epitopes are immunogenic. Conversely, 99.9% of bacterial genomes contain multiple cold shock proteins, and 46% carry a nonimmunogenic form. We uncovered a mechanism for immune evasion, intrabacterial antagonism, where a nonimmunogenic cold shock protein blocks perception of immunogenic forms encoded in the same genome. These data will lay the foundation for immune receptor deployment and engineering based on natural variation.


Asunto(s)
Arabidopsis , Epítopos , Solanum lycopersicum , Epítopos/inmunología , Solanum lycopersicum/inmunología , Solanum lycopersicum/genética , Solanum lycopersicum/microbiología , Arabidopsis/inmunología , Arabidopsis/genética , Genoma Bacteriano , Moléculas de Patrón Molecular Asociado a Patógenos/inmunología , Moléculas de Patrón Molecular Asociado a Patógenos/metabolismo , Inmunidad de la Planta/genética , Inmunidad de la Planta/inmunología , Factor Tu de Elongación Peptídica/genética , Factor Tu de Elongación Peptídica/inmunología , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/genética , Bacterias/inmunología , Bacterias/genética , Proteínas y Péptidos de Choque por Frío/genética , Proteínas y Péptidos de Choque por Frío/inmunología , Proteínas y Péptidos de Choque por Frío/metabolismo
2.
Biomolecules ; 14(3)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38540704

RESUMEN

Bis-indole derived compounds such as 1,1-bis(3'-indolyl)-1-(3,5-disubstitutedphenyl) methane (DIM-3,5) and the corresponding 4-hydroxyl analogs (DIM8-3,5) are NR4A1 ligands that act as inverse NR4A1 agonists and are potent inhibitors of tumor growth. The high potency of several DIM-3,5 analogs (IC50 < 1 mg/kg/day), coupled with the >60% similarity of the ligand-binding domains (LBDs) of NR4A1 and NR4A2 and the pro-oncogenic activities of both receptors lead us to hypothesize that these compounds may act as dual NR4A1 and NR4A2 ligands. Using a fluorescence binding assay, it was shown that 22 synthetic DIM8-3,5 and DIM-3,5 analogs bound the LBD of NR4A1 and NR4A2 with most KD values in the low µM range. Moreover, the DIM-3,5 and DIM8-3,5 analogs also decreased NR4A1- and NR4A2-dependent transactivation in U87G glioblastoma cells transfected with GAL4-NR4A1 or GAL4-NR4A2 chimeras and a UAS-luciferase reporter gene construct. The DIM-3,5 and DIM8-3,5 analogs were cytotoxic to U87 glioblastoma and RKO colon cancer cells and the DIM-3,5 compounds were more cytotoxic than the DIM8-3,5 compounds. These studies show that both DIM-3,5 and DIM8-3,5 compounds previously identified as NR4A1 ligands bind both NR4A1 and NR4A2 and are dual NR4A1/2 ligands.


Asunto(s)
Glioblastoma , Humanos , Ligandos , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Línea Celular Tumoral , Indoles/farmacología , Indoles/química , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo
3.
PLoS One ; 19(3): e0298799, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38457452

RESUMEN

BACKGROUND: Contact tracing is a key component in controlling the spread of COVID-19, however little research has focused on learning from the experiences of contact tracing staff. Harnessing learning from those in this role can provide valuable insights into the process of contact tracing and how best to support staff in this crucial role. METHODS: Thematic analysis was used to analyse 47 semi-structured interviews conducted with contact tracing staff via telephone or Zoom at three time points in 2021: March, May and September-October. RESULTS: Six themes related to the contact tracing role were identified, including training, workforce culture, systems issues, motivation and support. While initially nervous in the role, participants were motivated to contribute to the pandemic response and believed the role provided them with valuable transferable skills. Participants described the training as having improved over time while desiring more proactive training. Sources of frustration included a perceived lack of opportunity for feedback and involvement in process changes, feelings of low autonomy, and a perception of high staff turnover. Participants expressed a need for improved communication of formal emotional supports. Increased managerial support and provision of opportunities for career advancement may contribute to increased motivation among staff. CONCLUSIONS: These findings identify the experiences of contact tracing staff working during the COVID-19 pandemic, and have important implications for the improvement of the contact tracing system. Recommendations based on learning from participants offer suggestions as to how best to support the needs of contact tracing staff during a pandemic response.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Trazado de Contacto , Pandemias , Irlanda/epidemiología , Comunicación
5.
bioRxiv ; 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37790530

RESUMEN

Plants and animals detect biomolecules termed Microbe-Associated Molecular Patterns (MAMPs) and induce immunity. Agricultural production is severely impacted by pathogens which can be controlled by transferring immune receptors. However, most studies use a single MAMP epitope and the impact of diverse multi-copy MAMPs on immune induction is unknown. Here we characterized the epitope landscape from five proteinaceous MAMPs across 4,228 plant-associated bacterial genomes. Despite the diversity sampled, natural variation was constrained and experimentally testable. Immune perception in both Arabidopsis and tomato depended on both epitope sequence and copy number variation. For example, Elongation Factor Tu is predominantly single copy and 92% of its epitopes are immunogenic. Conversely, 99.9% of bacterial genomes contain multiple Cold Shock Proteins and 46% carry a non-immunogenic form. We uncovered a new mechanism for immune evasion, intrabacterial antagonism, where a non-immunogenic Cold Shock Protein blocks perception of immunogenic forms encoded in the same genome. These data will lay the foundation for immune receptor deployment and engineering based on natural variation.

6.
Plant J ; 117(1): 7-22, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37844152

RESUMEN

Plant intracellular immune receptors, primarily nucleotide-binding, leucine-rich repeat proteins (NLRs), detect pathogen effector proteins and activate NLR-triggered immunity (NTI). Recently, 'sensor' NLRs have been reported to function with 'helper' NLRs to activate immunity. We investigated the role of two helper NLRs, Nrc2 and Nrc3, on immunity in tomato to the bacterial pathogen Pseudomonas syringae pv. tomato (Pst) mediated by the sensor NLR Prf and the Pto kinase. An nrc2/nrc3 mutant no longer activated Prf/Pto-mediated NTI to Pst containing the effectors AvrPto and AvrPtoB. An nrc3 mutant showed intermediate susceptibility between wild-type plants and a Prf mutant, while an nrc2 mutant developed only mild disease. These observations indicate that Nrc2 and Nrc3 act additively in Prf-/Pto-mediated immunity. We examined at what point Nrc2 and Nrc3 act in the Prf/Pto-mediated immune response. In the nrc2/3 mutant, programmed cell death (PCD) normally induced by constitutively active variants of AvrPtoB, Pto, or Prf was abolished, but that induced by M3Kα or Mkk2 was not. PCD induced by a constitutively active Nrc3 was also abolished in a Nicotiana benthamiana line with reduced expression of Prf. MAPK activation triggered by expression of AvrPto in the wild-type tomato plants was completely abolished in the nrc2/3 mutant. These results indicate that Nrc2 and Nrc3 act with Prf/Pto and upstream of MAPK signaling. Nrc2 and Nrc3 were not required for PCD triggered by Ptr1, another sensor NLR-mediating Pst resistance, although these helper NLRs do appear to be involved in resistance to certain Pst race 1 strains.


Asunto(s)
Proteínas Serina-Treonina Quinasas , Solanum lycopersicum , Proteínas Serina-Treonina Quinasas/metabolismo , Solanum lycopersicum/genética , Pseudomonas syringae/fisiología , Apoptosis , Proteínas de Plantas/metabolismo , Enfermedades de las Plantas/microbiología , Proteínas Bacterianas/metabolismo
7.
Adv Neonatal Care ; 24(3): 212-218, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38127593

RESUMEN

BACKGROUND: The Chandler Regional Medical Center (CRMC) neonatal intensive care unit (NICU) began a phased implementation of Eat-Sleep-Console (ESC) for the management of those at risk for neonatal opioid withdrawal syndrome (NOWS). PURPOSE: The purpose of this initiative is to track short-term outcomes as well as the program's effect on nursing workflow and job performance rating/satisfaction. METHODS: A retrospective review of the ESC implementation process at CRMC from the years 2018-2020. The study consisted of 3 epochs: (1) traditional pharmacologic management; (2) parent-led ESC management; and (3) parent/nurse-led ESC management. Length of stay (LOS), treatment pathway assignment, and proportion of infants treated with pharmacologic agents were compared between epochs. In addition, a survey of NICU nursing staff was distributed to measure nurses' perceptions and attitudes towards the ESC program and the management of infants with NOWS. RESULTS: The proportion of infants treated via ESC increased (0%, 53%, and 100%), with an associated decrease in LOS (18.4, 10.5, and 9.3 days) during each epoch of the study period. Thirty-seven nurses completed the survey, with 94% of nurses reporting being comfortable caring for ESC patients and 89% feeling supported in their ESC nursing assignments, with only 11% stating that caring for ESC patients significantly alters their other nursing care processes. IMPLICATIONS FOR PRACTICE AND RESEARCH: Implementation of an ESC treatment program for infants with NOWS significantly decreased LOS and the proportion of infants treated pharmacologically. This phased implementation process was not associated with self-reported negative nursing perceptions of the program and its treatment goals/outcomes.


Asunto(s)
Hospitales Comunitarios , Unidades de Cuidado Intensivo Neonatal , Síndrome de Abstinencia Neonatal , Humanos , Síndrome de Abstinencia Neonatal/enfermería , Síndrome de Abstinencia Neonatal/terapia , Recién Nacido , Estudios Retrospectivos , Tiempo de Internación/estadística & datos numéricos , Femenino , Enfermería Neonatal/métodos , Masculino , Analgésicos Opioides/uso terapéutico , Analgésicos Opioides/efectos adversos , Actitud del Personal de Salud
8.
Food Chem ; 437(Pt 2): 137906, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-37939420

RESUMEN

This study investigated the effects of aerobic and anaerobic growth and proteolytic enzymes on the amino acid content of yeast hydrolysates in relation to taste and nutrition. Saccharomyces cerevisiae ATCC5574 was grown under fed-batch aerobic or batch anaerobic conditions. Intracellular glutamic acid (Glu) concentrations were 18-fold higher in aerobic yeast. Hydrolysis with papain and alkaline protease released more amino acids (AA) than simple autolysis or hydrolysis with bromelain, most significantly when applied to aerobic yeast (∼2-fold increase). Autolysates and bromelain hydrolysates from aerobic yeast had low levels of bitter and essential AAs, with high levels of umami Glu. Papain and alkaline protease hydrolysates of aerobic yeast had high levels of umami, bitter and essential AAs. Autolysates/hydrolysates from anaerobic yeast had moderate, high, and low levels of bitter, essential and umami AAs. Selection of both yeast growth conditions and hydrolysis enzyme can manipulate the free AA profile and yield of hydrolysates.


Asunto(s)
Bromelaínas , Péptido Hidrolasas , Péptido Hidrolasas/metabolismo , Bromelaínas/metabolismo , Saccharomyces cerevisiae/metabolismo , Aminoácidos , Gusto , Papaína/metabolismo , Hidrólisis , Ácido Glutámico , Hidrolisados de Proteína/química
9.
JACC Basic Transl Sci ; 8(10): 1318-1330, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38094696

RESUMEN

No studies have explored a functional role for bone morphogenetic protein (BMP)-9, a transforming growth factor-ß superfamily ligand, in cardiac remodeling after myocardial infarction (MI). Using BMP-9 null mice, we observed that loss of BMP-9 decreases survival and increases cardiac rupture after MI. We further observed that loss of BMP-9 not only increases collagen abundance, but also promotes matrix metalloproteinase-9 activity and collagen degradation after MI. These findings identify BMP-9 as a necessary component of cardiac remodeling after MI and a potentially important target of therapy to improve outcomes after MI.

10.
Artículo en Inglés | MEDLINE | ID: mdl-38064044

RESUMEN

The functional role of TGFß type I receptor, activin-like kinase (ALK)-1 in post-myocardial infarction (MI) cardiac remodeling is unknown. We hypothesize that reduced ALK1 activity reduces survival and promotes cardiac fibrosis after MI. MI was induced in wild-type (WT), and ALK+/- mice by left coronary ligation. After 14 days ALK1+/- mice had reduced survival with a higher rate of cardiac rupture compared to WT mice. ALK1+/- left ventricles (LVs) had increased volumes at the end of systole and at the end of diastole. After MI ALK1+/- LVs had increased profibrotic SMAD3 signaling, type 1 collagen, and fibrosis as well as increased levels of TGFß1 co-receptor, endoglin, VEGF, and ALK1 ligands BMP9 and BMP10. ALK1+/- LVs had decreased levels of stromal-derived factor 1α. These data identify the critical role of ALK1 in post-MI survival and cardiac remodeling and implicate ALK1 as a potential therapeutic target to improve survival after MI.

11.
Chem Biodivers ; 20(11): e202300602, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37798811

RESUMEN

This study compared free and bound phenolic compounds in various marine microalgae species. It assessed total phenolic content (TPC), total flavonoid content (TFC) and total condensed tannin content (TCT) and their antioxidant capacities using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⋅+ ) radical cation-based assay and ferric ion reducing antioxidant power assay. Liquid chromatography-mass spectrometry (LC-MS) was also employed to characterize the phenolic profiling. Results showed that free phenolic compounds ranged from 1.83-6.45 mg GAE/g d. w., while bound phenolic compounds ranged from 4.03-26.03 mg GAE/g d. w., indicating significant differences. These variations were consistent across assays, highlining unique profiles in different species. A total 10 phenolics were found in these seven microalgae, including 1 phenolic acid, 6 flavonoids, 1 other polyphenol and 2 lignans. 4'-O-methyl-(-)-epigallocatechin 7-O-glucuronide and chrysoeriol 7-O-glucoside in microalgae were firstly reported in microalgal samples. These findings have implications for future applications in industries.


Asunto(s)
Antioxidantes , Microalgas , Antioxidantes/química , Flavonoides/química , Fenoles/química , Extractos Vegetales/química
12.
Surg Endosc ; 37(12): 9509-9513, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37700013

RESUMEN

INTRODUCTION: Body mass index (BMI) > 50 kg/m2 is associated with relatively increased morbidity and mortality with bariatric surgery (BS). There is reluctance to consider these patients operative candidates without preoperative weight loss. Glucagon-like peptide-1 (GLP-1) agonists have demonstrated effective weight loss in the post-BS setting. This study aims to determine the safety and efficacy of GLP-1 agonists in the pre-habilitation of patients with BMI > 50 kg/m2. METHODS: This is a retrospective review of bariatric surgery patients with BMI > 50 kg/m2 from a single bariatric center. Patients were compared by preoperative GLP-1 therapy status. All patients received medical, surgical, psychiatric, and nutritional evaluation and counseling. Preoperative BMI, change in weight from program intake until surgery, time to surgery, and perioperative complications were evaluated. RESULTS: 31 patients were included in the analysis. 18 (58%) received a GLP-1 agonist preoperatively. GLP-1 agonist use was associated with a 5.5 ± 3.2-point reduction in BMI compared to 2.9 ± 2.4 amongst controls (p = 0.026). There was no difference in the mean length of time in the bariatric program prior to surgery between groups (p = 0.332). There were no reported complications related to GLP-1 use in the preoperative setting and no difference in perioperative complications between groups (p = 0.245). DISCUSSION: GLP-1 agonist use in patients with a BMI > 50 kg/m2 results in significantly more weight loss prior to bariatric surgery, without increased time to surgery or complication rate. Further study is required to evaluate the long-term impact of preoperative GLP-1 agonist use prior to bariatric surgery. This therapy may improve perioperative and long-term outcomes in the very high-risk BMI population.


Asunto(s)
Cirugía Bariátrica , Obesidad Mórbida , Humanos , Estudios de Cohortes , Cirugía Bariátrica/métodos , Estudios Retrospectivos , Índice de Masa Corporal , Pérdida de Peso , Péptido 1 Similar al Glucagón , Obesidad Mórbida/complicaciones , Obesidad Mórbida/cirugía
13.
J Med Entomol ; 60(6): 1364-1373, 2023 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-37643752

RESUMEN

House fly (Musca domestica L.) (Diptera: Muscidae) populations can negatively impact poultry layer facilities, posing a risk to human and animal health and egg food safety. House flies quickly develop resistance to traditional chemical control methods; therefore, improved biological control may provide opportunities for improved integrated pest management (IPM) programs. Biological control methods currently used include augmentative releases of pteromalid pupal parasitoids and application of the fungal entomopathogen Beauveria bassiana (Balsamo) Vuillemin. This study used bioassays to compare the impact of different B. bassiana strains on survival of house flies and of 3 species of filth fly parasitoids. The B. bassiana that were compared were 3 new field-collected isolates, an older field-collected isolate (L90), and a common commercially available strain (GHA). Flies and parasitoids were exposed to filter paper treated with 1.5 × 109 spores of each strain and a control. All field-isolated strains induced lower mean survival times in house flies than GHA did. The results for all species of parasitoids demonstrated less difference among the treatment groups and the control than in-house flies. Although there was some effect of B. bassiana exposure on parasitoid mortality, the expected spatial separation of parasitoids from areas of application may offer some protection. Using the most effective tested strains of B. bassiana and filth fly parasitoids jointly could be a biological component of an IPM plan for fly control in poultry facilities.


Asunto(s)
Beauveria , Moscas Domésticas , Himenópteros , Muscidae , Humanos , Animales , Moscas Domésticas/microbiología , Control Biológico de Vectores/métodos
14.
Endocrinology ; 164(10)2023 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-37652054

RESUMEN

Nuclear receptor 4A1 (NR4A1) plays an important role in endometriosis progression; levels of NR4A1 in endometriotic lesions are higher than in normal endometrium, and substituted bis-indole analogs (NR4A1) antagonists suppress endometriosis progression in mice with endometriosis. In addition, the flavonoids kaempferol and quercetin are natural products that directly bind NR4A1 and significantly repress the intrinsic NR4A1-dependent transcriptional activity in human endometriotic epithelial and stromal cells and Ishikawa endometrial cancer cells. NR4A1 knockdown and inhibition of NR4A1 by kaempferol and quercetin suppressed proliferation of human endometriotic epithelial cells and Ishikawa cells by inhibiting epidermal growth factor receptor/c-Myc/survivin-mediated growth-promoting and survival pathways, The mammalian target of rapamycin (mTOR) signaling and αSMA/CTGF/COL1A1/FN-mediated fibrosis signaling but increasing Thioredoxin domain Containing 5/SESN2-mediated oxidative/estrogen receptors stress signaling. In human endometriotic stromal cells, NR4A1 knockdown and inhibition of NR4A1 by kaempferol and quercetin primarily inhibited mTOR signaling by suppressing proliferation of human endometrial stromal cells. In addition, kaempferol and quercetin treatment also effectively suppressed the growth of endometriotic lesions in mice with endometriosis compared with the vehicle without any body weight changes. Therefore, kaempferol and quercetin are NR4A1 antagonists with potential as nutritional therapy for endometriosis.


Asunto(s)
Endometriosis , Quercetina , Humanos , Femenino , Animales , Ratones , Quercetina/farmacología , Quercetina/uso terapéutico , Flavonoides , Endometriosis/tratamiento farmacológico , Quempferoles/farmacología , Quempferoles/uso terapéutico , Serina-Treonina Quinasas TOR , Mamíferos , Sestrinas , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética
15.
Front Cardiovasc Med ; 10: 1223244, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37435054

RESUMEN

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiovascular disorder affecting 1 in 500 people in the general population. Characterized by asymmetric left ventricular hypertrophy, cardiomyocyte disarray and cardiac fibrosis, HCM is a highly complex disease with heterogenous clinical presentation, onset and complication. While mutations in sarcomere genes can account for a substantial proportion of familial cases of HCM, 40%-50% of HCM patients do not carry such sarcomere variants and the causal mutations for their diseases remain elusive. Recently, we identified a novel variant of the alpha-crystallin B chain (CRYABR123W) in a pair of monozygotic twins who developed concordant HCM phenotypes that manifested over a nearly identical time course. Yet, how CRYABR123W promotes the HCM phenotype remains unclear. Here, we generated mice carrying the CryabR123W knock-in allele and demonstrated that hearts from these animals exhibit increased maximal elastance at young age but reduced diastolic function with aging. Upon transverse aortic constriction, mice carrying the CryabR123W allele developed pathogenic left ventricular hypertrophy with substantial cardiac fibrosis and progressively decreased ejection fraction. Crossing of mice with a Mybpc3 frame-shift model of HCM did not potentiate pathological hypertrophy in compound heterozygotes, indicating that the pathological mechanisms in the CryabR123W model are independent of the sarcomere. In contrast to another well-characterized CRYAB variant (R120G) which induced Desmin aggregation, no evidence of protein aggregation was observed in hearts expressing CRYABR123W despite its potent effect on driving cellular hypertrophy. Mechanistically, we uncovered an unexpected protein-protein interaction between CRYAB and calcineurin. Whereas CRYAB suppresses maladaptive calcium signaling in response to pressure-overload, the R123W mutation abolished this effect and instead drove pathologic NFAT activation. Thus, our data establish the CryabR123W allele as a novel genetic model of HCM and unveiled additional sarcomere-independent mechanisms of cardiac pathological hypertrophy.

16.
NPJ Vaccines ; 8(1): 101, 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37443366

RESUMEN

Chemical cross-linking is used to stabilize protein structures with additional benefits of pathogen and toxin inactivation for vaccine use, but its use has been restricted by the potential for local or global structural distortion. This is of particular importance when the protein in question requires a high degree of structural conservation for inducing a biological outcome such as the elicitation of antibodies to conformationally sensitive epitopes. The HIV-1 envelope glycoprotein (Env) trimer is metastable and shifts between different conformational states, complicating its use as a vaccine antigen. Here we have used the hetero-bifunctional zero-length reagent 1-Ethyl-3-(3-Dimethylaminopropyl)-Carbodiimide (EDC) to cross-link two soluble Env trimers, selected well-folded trimer species using antibody affinity, and transferred this process to good manufacturing practice (GMP) for experimental medicine use. Cross-linking enhanced trimer stability to biophysical and enzyme attack. Cryo-EM analysis revealed that cross-linking retained the overall structure with root-mean-square deviations (RMSDs) between unmodified and cross-linked Env trimers of 0.4-0.5 Å. Despite this negligible distortion of global trimer structure, we identified individual inter-subunit, intra-subunit, and intra-protomer cross-links. Antigenicity and immunogenicity of the trimers were selectively modified by cross-linking, with cross-linked ConS retaining bnAb binding more consistently than ConM. Thus, the EDC cross-linking process improves trimer stability whilst maintaining protein folding, and is readily transferred to GMP, consistent with the more general use of this approach in protein-based vaccine design.

17.
Nat Commun ; 14(1): 4546, 2023 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-37507365

RESUMEN

The generation of high-quality antibody responses to Plasmodium falciparum (Pf) circumsporozoite protein (PfCSP), the primary surface antigen of Pf sporozoites, is paramount to the development of an effective malaria vaccine. Here we present an in-depth structural and functional analysis of a panel of potent antibodies encoded by the immunoglobulin heavy chain variable (IGHV) gene IGHV3-33, which is among the most prevalent and potent antibody families induced in the anti-PfCSP immune response and targets the Asn-Ala-Asn-Pro (NANP) repeat region. Cryo-electron microscopy (cryo-EM) reveals a remarkable spectrum of helical antibody-PfCSP structures stabilized by homotypic interactions between tightly packed fragments antigen binding (Fabs), many of which correlate with somatic hypermutation. We demonstrate a key role of these mutated homotypic contacts for high avidity binding to PfCSP and in protection from Pf malaria infection. Together, these data emphasize the importance of anti-homotypic affinity maturation in the frequent selection of IGHV3-33 antibodies and highlight key features underlying the potent protection of this antibody family.


Asunto(s)
Vacunas contra la Malaria , Malaria Falciparum , Malaria , Humanos , Microscopía por Crioelectrón , Plasmodium falciparum/genética , Malaria/prevención & control , Malaria Falciparum/prevención & control , Proteínas Protozoarias/química , Anticuerpos , Anticuerpos Antiprotozoarios
18.
Mol Ther Nucleic Acids ; 32: 995-1009, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37332476

RESUMEN

Angiogenesis is critical for tissue repair following myocardial infarction (MI), which is exacerbated under insulin resistance or diabetes. MicroRNAs are regulators of angiogenesis. We examined the metabolic regulation of miR-409-3p in post-infarct angiogenesis. miR-409-3p was increased in patients with acute coronary syndrome (ACS) and in a mouse model of acute MI. In endothelial cells (ECs), miR-409-3p was induced by palmitate, while vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) decreased its expression. Overexpression of miR-409-3p decreased EC proliferation and migration in the presence of palmitate, whereas inhibition had the opposite effects. RNA sequencing (RNA-seq) profiling in ECs identified DNAJ homolog subfamily B member 9 (DNAJB9) as a target of miR-409-3p. Overexpression of miR-409-3p decreased DNAJB9 mRNA and protein expression by 47% and 31% respectively, while enriching DNAJB9 mRNA by 1.9-fold after Argonaute2 microribonucleoprotein immunoprecipitation. These effects were mediated through p38 mitogen-activated protein kinase (MAPK). Ischemia-reperfusion (I/R) injury in EC-specific miR-409-3p knockout (KO) mice (miR-409ECKO) fed a high-fat, high-sucrose diet increased isolectin B4 (53.3%), CD31 (56%), and DNAJB9 (41.5%). The left ventricular ejection fraction (EF) was improved by 28%, and the infarct area was decreased by 33.8% in miR-409ECKO compared with control mice. These findings support an important role of miR-409-3p in the angiogenic EC response to myocardial ischemia.

19.
New Phytol ; 239(5): 1935-1953, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37334551

RESUMEN

Some nucleotide-binding and leucine-rich repeat receptors (NLRs) indirectly detect pathogen effectors by monitoring their host targets. In Arabidopsis thaliana, RIN4 is targeted by multiple sequence-unrelated effectors and activates immune responses mediated by RPM1 and RPS2. These effectors trigger cell death in Nicotiana benthamiana, but the corresponding NLRs have yet not been identified. To identify N. benthamiana NLRs (NbNLRs) that recognize Arabidopsis RIN4-targeting effectors, we conducted a rapid reverse genetic screen using an NbNLR VIGS library. We identified that the N. benthamiana homolog of Ptr1 (Pseudomonas tomato race 1) recognizes the Pseudomonas effectors AvrRpt2, AvrRpm1, and AvrB. We demonstrated that recognition of the Xanthomonas effector AvrBsT and the Pseudomonas effector HopZ5 is conferred independently by the N. benthamiana homolog of Ptr1 and ZAR1. Interestingly, the recognition of HopZ5 and AvrBsT is contributed unequally by Ptr1 and ZAR1 in N. benthamiana and Capsicum annuum. In addition, we showed that the RLCK XII family protein JIM2 is required for the NbZAR1-dependent recognition of AvrBsT and HopZ5. The recognition of sequence-unrelated effectors by NbPtr1 and NbZAR1 provides an additional example of convergently evolved effector recognition. Identification of key components involved in Ptr1 and ZAR1-mediated immunity could reveal unique mechanisms of expanded effector recognition.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas/metabolismo , Bacterias/metabolismo , Proteínas Portadoras/metabolismo , Pseudomonas , Receptores Inmunológicos/metabolismo , Proteínas Bacterianas/metabolismo , Pseudomonas syringae/metabolismo , Enfermedades de las Plantas/microbiología , Proteínas de Arabidopsis/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo
20.
BMC Health Serv Res ; 23(1): 602, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37291553

RESUMEN

BACKGROUND: Contact tracing is a key control measure in the response to the COVID-19 pandemic. While quantitative research has been conducted on the psychological impact of the pandemic on other frontline healthcare workers, none has explored the impact on contact tracing staff. METHODS: A longitudinal study was conducted using two repeated measures with contact tracing staff employed in Ireland during the COVID-19 pandemic using two-tailed independent samples t tests and exploratory linear mixed models. RESULTS: The study sample included 137 contact tracers in March 2021 (T1) and 218 in September 2021 (T3). There was an increase from T1 to T3 in burnout related exhaustion (p < 0·001), post-traumatic stress disorder (PTSD) symptom scores (p < 0·001), mental distress (p < 0·01), perceived stress (p < 0·001) and tension and pressure (p < 0·001). In those aged 18-30, there was an increase in exhaustion related burnout (p < 0·01), PTSD symptoms (p < 0·05), and tension and pressure scores (p < 0·05). Additionally, participants with a background in healthcare showed an increase in PTSD symptom scores by T3 (p < 0·001), reaching mean scores equivalent to those of participants who did not have a background in healthcare. CONCLUSIONS: Contact tracing staff working during the COVID-19 pandemic experienced an increase in adverse psychological outcomes. These findings highlight a need for further research on psychological supports required by contact tracing staff with differing demographic profiles.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Trazado de Contacto , Estudios Longitudinales , Pandemias , Agotamiento Psicológico , Personal de Salud
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