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1.
Nucleic Acids Res ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38554105

RESUMO

During assembly, ribosomal particles in bacteria fold according to energy landscapes comprised of multiple parallel pathways. Cryo-electron microscopy studies have identified a critical maturation step that occurs during the late assembly stages of the 50S subunit in Bacillus subtilis. This step acts as a point of convergency for all the parallel assembly pathways of the subunit, where an assembly intermediate accumulates in a 'locked' state, causing maturation to pause. Assembly factors then act on this critical step to 'unlock' the last maturation steps involving the functional sites. Without these factors, the 50S subunit fails to complete its assembly, causing cells to die due to a lack of functional ribosomes to synthesize proteins. In this review, we analyze these findings in B. subtilis and examine other cryo-EM studies that have visualized assembly intermediates in different bacterial species, to determine if convergency points in the ribosome assembly process are a common theme among bacteria. There are still gaps in our knowledge, as these methodologies have not yet been applied to diverse species. However, identifying and characterizing these convergency points can reveal how different bacterial species implement unique mechanisms to regulate critical steps in the ribosome assembly process.

2.
Cell Rep Med ; 5(3): 101433, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38401547

RESUMO

Inclusion of defined quantities of the two major surface proteins of influenza virus, hemagglutinin (HA) and neuraminidase (NA), could benefit seasonal influenza vaccines. Recombinant HA and NA multimeric proteins derived from three influenza serotypes, H1N1, H3N2, and type B, are surface displayed on nanoliposomes co-loaded with immunostimulatory adjuvants, generating "hexaplex" particles that are used to immunize mice. Protective immune responses to hexaplex liposomes involve functional antibody elicitation against each included antigen, comparable to vaccination with monovalent antigen particles. When compared to contemporary recombinant or adjuvanted influenza virus vaccines, hexaplex liposomes perform favorably in many areas, including antibody production, T cell activation, protection from lethal virus challenge, and protection following passive sera transfer. Based on these results, hexaplex liposomes warrant further investigation as an adjuvanted recombinant influenza vaccine formulation.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Vacinas contra Influenza , Influenza Humana , Infecções por Orthomyxoviridae , Camundongos , Animais , Humanos , Hemaglutininas , Neuraminidase/genética , Vírus da Influenza A Subtipo H3N2 , Lipossomos , Adjuvantes Imunológicos , Vacinas Sintéticas
3.
Proc Natl Acad Sci U S A ; 121(7): e2306993121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315848

RESUMO

Puromycin is covalently added to the nascent chain of proteins by the peptidyl transferase activity of the ribosome and the dissociation of the puromycylated peptide typically follows this event. It was postulated that blocking the translocation of the ribosome with emetine could retain the puromycylated peptide on the ribosome, but evidence against this has recently been published [Hobson et al., Elife 9, e60048 (2020); and Enam et al., Elife 9, e60303 (2020)]. In neurons, puromycylated nascent chains remain in the ribosome even in the absence of emetine, yet direct evidence for this has been lacking. Using biochemistry and cryoelectron microscopy, we show that the puromycylated peptides remain in the ribosome exit channel in the large subunit in a subset of neuronal ribosomes stalled in the hybrid state. These results validate previous experiments to localize stalled polysomes in neurons and provide insight into how neuronal ribosomes are stalled. Moreover, in these hybrid-state neuronal ribosomes, anisomycin, which usually blocks puromycylation, competes poorly with puromycin in the puromycylation reaction, allowing a simple assay to determine the proportion of nascent chains that are stalled in this state. In early hippocampal neuronal cultures, over 50% of all nascent peptides are found in these stalled polysomes. These results provide insights into the stalling mechanisms of neuronal ribosomes and suggest that puromycylated peptides can be used to reveal subcellular sites of hybrid-state stalled ribosomes in neurons.


Assuntos
Emetina , Ribossomos , Puromicina/farmacologia , Microscopia Crioeletrônica , Emetina/análise , Emetina/metabolismo , Ribossomos/metabolismo , Biossíntese de Proteínas , Peptídeos/metabolismo , Neurônios/metabolismo
4.
Small ; 20(9): e2304534, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37849036

RESUMO

The receptor binding domain (RBD) of the SARS-CoV-2 Spike (S) glycoprotein is an appealing immunogen, but associated vaccine approaches must overcome the hapten-like nature of the compact protein and adapt to emerging variants with evolving RBD sequences. Here, a vaccine manufacturing methodology is proposed comprising a sterile-filtered freeze-dried lipid cake formulation that can be reconstituted with liquid proteins to instantaneously form liposome-displayed protein nanoparticles. Mannitol is used as a bulking agent and a small amount of Tween-80 surfactant is required to achieve reconstituted submicron particles that do not precipitate prior to usage. The lipid particles include an E. coli-derived monophosphoryl lipid A (EcML) for immunogenicity, and cobalt porphyrin-phospholipid (CoPoP) for antigen display. Reconstitution of the lipid cake with aqueous protein results in rapid conversion of the RBD into intact liposome-bound format prior to injection. Protein particles can readily be formed with sequent-divergent RBD proteins derived from the ancestral or Omicron strains. Immunization of mice elicits antibodies that neutralize respective viral strains. When K18-hACE2 transgenic mice are immunized and challenged with ancestral SARS-CoV-2 or the Omicron BA.5 variant, both liquid liposomes displaying the RBD and rapid reconstituted particles protect mice from infection, as measured by the viral load in the lungs and nasal turbinates.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Animais , Camundongos , SARS-CoV-2 , Escherichia coli , Lipossomos , COVID-19/prevenção & controle , Lipídeos
5.
Vet Pathol ; : 3009858231214025, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38006226

RESUMO

This study describes the clinical, gross, and histologic findings in 17 cases of aneurysms in bearded dragons (Pogona vitticeps). The clinical presentation ranged from incidental to sudden and unexpected death. The affected vasculature was predominantly arterial; however, based on the topographical locations of the lesions, gross structure, and drainage, some veins were likely involved. Magnetic resonance imaging and computerized tomography scans of 1 animal showed a large aneurysm of the internal carotid artery extending from near its aortic origin into the caudal head. Aneurysms were organized in 5 groups based on their anatomical locations: cephalic, cranial coelom (for all near the heart), caudal coelom (for the mesenteric vessels and descending aorta), limbs, and tail. The cranial coelomic region was the most prevalent location. Gross findings were large hematomas or red serosanguineous fluid filling the adjacent area, as most of the aneurysms (94%) were ruptured at the time of the study. The main histological findings were degenerative changes of the vessel walls characterized by moderate to severe disruption of the collagen and elastic fibers of the tunica media and adventitia (100%), followed by thickening of the intima with thrombi formation (54%) and dissecting hematoma of the vessel wall (47%). Vasculitis (29%), mineralization (6%), and lipid deposits (6%) in the vessel wall were observed occasionally. Based on these findings, the vascular dilations and ruptures observed in bearded dragons likely are associated with weakness of the vessel walls caused by degenerative changes in the intimal and medial tunics.

6.
Animals (Basel) ; 13(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37760228

RESUMO

Ovine pulmonary adenocarcinoma (OPA) is a contagious respiratory tumor of small ruminants, manifesting in chronic weight loss and respiratory failure. Infection with the betaretrovirus jaagsiekte sheep retrovirus (JSRV) is the cause of OPA. Here, we describe the gross and microscopic features of twenty-six sheep and one goat with naturally occurring JSRV-associated OPA. All the animals included in this study had pulmonary lesions morphologically consistent with OPA, but the majority of the observed lesions demonstrated features of both the classical and the atypical form of OPA, and were, therefore, classified grossly as mixed. The gross lesions were located mainly in the cranial pulmonary lobes, were multifocal to coalescing, variable in number and size, flat to slightly raised, firm, and white to grey. Histologically, the cases were classified according to the predominant architectural patterns as lepidic, papillary, acinar, or mixed; the mixed histological pattern was the most prevalent. The aim of this study was to describe the gross and microscopic spectrum of OPA in naturally infected small ruminants from Spain. The mixed form of OPA is less commonly reported, and can be confused with other concurrent pulmonary pathologies (such as BALT hyperplasia in SRLV-associated pneumonia or lungworm granulomas).

7.
Nat Struct Mol Biol ; 30(10): 1468-1480, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37653244

RESUMO

Ribosome assembly is orchestrated by many assembly factors, including ribosomal RNA methyltransferases, whose precise role is poorly understood. Here, we leverage the power of cryo-EM and machine learning to discover that the E. coli methyltransferase KsgA performs a 'proofreading' function in the assembly of the small ribosomal subunit by recognizing and partially disassembling particles that have matured but are not competent for translation. We propose that this activity allows inactive particles an opportunity to reassemble into an active state, thereby increasing overall assembly fidelity. Detailed structural quantifications in our datasets additionally enabled the expansion of the Nomura assembly map to highlight rRNA helix and r-protein interdependencies, detailing how the binding and docking of these elements are tightly coupled. These results have wide-ranging implications for our understanding of the quality-control mechanisms governing ribosome biogenesis and showcase the power of heterogeneity analysis in cryo-EM to unveil functionally relevant information in biological systems.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/metabolismo , Subunidades Ribossômicas Menores/metabolismo , Proteínas de Escherichia coli/metabolismo , RNA Ribossômico/metabolismo , Proteínas Ribossômicas/metabolismo
8.
Bioconjug Chem ; 34(8): 1467-1476, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37499133

RESUMO

A series of generation 3-5 dendrons based on a bis(2,2-hydroxymethylpropionic acid) (bis-MPA) scaffold bearing three respective lengths of linear poly(ethylene glycol) at their periphery and a dibenzocyclooctyne unit at their core was prepared. These dendrons were appended to the surface of azide-decorated α-chymotrypsin (α-CT) via strain-promoted azide-alkyne cycloaddition to yield a library of dendron-protein conjugates. These conjugates were characterized by FT-IR and NMR spectroscopy and were imaged using cryo-electron microscopy. The activity of the PEGylated α-CT-dendron conjugates was investigated using a small molecule (benzoyl-l-tyrosine p-nitroanilide) as well as different proteins of different sizes and crystallinities (casein and bovine serum albumin) as substrates. It was found that the activity of the conjugates toward the small molecule was largely retained, while the activity toward the proteins was significantly diminished. Furthermore, the results indicate that for most of the conjugates the PEG length had a more pronounced impact on enzyme activity than the dendron generation. Overall, the highest sieving ratios were found for α-CT-dendron conjugates decorated with G3-PEG2000, G4-PEG2000, and G5-PEG1000, with the latter two structures offering the best combination of sieving ratio and small molecule activity.


Assuntos
Dendrímeros , Dendrímeros/química , Microscopia Crioeletrônica , Azidas , Espectroscopia de Infravermelho com Transformada de Fourier , Polietilenoglicóis/química
9.
Br J Surg ; 110(9): 1180-1188, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37311694

RESUMO

BACKGROUND: The aim of this study was to compare the clinical outcomes between breast cancer patients who underwent axillary lymph node dissection with postoperative management using a polyethylene glycol-coated patch versus axillary drainage. The direct costs associated with both postoperative management strategies were also evaluated. METHODS: This was a multicentre RCT in women with breast cancer who underwent axillary lymph node dissection (ClinicalTrials.gov identifier: NCT04487561). Patients were randomly assigned (1 : 1) to receive either drainage or a polyethylene glycol-coated patch as postoperative management. The primary endpoints were the need for an emergency department visit for any event related to the surgery and the rate of seroma development. RESULTS: A total of 227 patients were included , 115 in the patch group (50.7 per cent) and 112 (29.4 per cent ) in the drainage group. The incidence of emergency department visits was significantly greater for patients with drainage versus a polyethylene glycol-coated patch (incidence rate difference 26.1 per cent, 95 per cent c.i. 14.5 to 37.7 per cent; P < 0.001). Conversely, the seroma rate was significantly higher in the polyethylene glycol-coated patch group (incidence rate difference 22.8 per cent, 95 per cent c.i. 6.7 to 38.9 per cent; P < 0.0055). Compared with drainage, using a polyethylene glycol-coated patch resulted in cost savings of €100.41 per patient. An incremental cost-effectiveness ratio analysis found that drainage was associated with an incremental cost-effectiveness ratio of €7594.4 for no need for hospital admission and €491.7 for no need for an emergency department visit. CONCLUSION: Compared with patients who received drainage after axillary lymph node dissection, the use of a polyethylene glycol-coated patch resulted in a higher rate of seroma, but a lower number of postoperative outpatient or emergency department visits and thus a reduction in overall costs.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Seroma/epidemiologia , Seroma/etiologia , Seroma/cirurgia , Excisão de Linfonodo/métodos , Drenagem/métodos , Hospitalização , Axila/patologia
10.
Front Endocrinol (Lausanne) ; 14: 1154158, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124725

RESUMO

Background/Aims: Chemokines are known to play critical roles mediating inflammation in many pathophysiological processes. The aim of this study was to investigate the role of chemokine receptor CCR4 and its ligands CCL17 and CCL22 in human morbid obesity. Methods: Circulating levels of CCL17 and CCL22 were measured in 60 morbidly obese patients (mean age, 45 ± 1 years; body mass index/BMI, 44 ± 1 kg/m2) who had undergone bariatric bypass surgery, and 20 control subjects. Paired subcutaneous (SCAT) and visceral adipose tissue (VCAT) from patients were analysed to measure expression of CCR4 and its ligands by RT-PCR, western blot and immunohistochemical analysis. The effects of CCR4 neutralization ex vivo on leukocyte-endothelial cells were also evaluated. Results: Compared with controls, morbidly obese patients presented higher circulating levels of CCL17 (p=0.029) and CCL22 (p<0.001) and this increase was positively correlated with BMI (p=0.013 and p=0.0016), and HOMA-IR Index (p=0.042 and p< 0.001). Upregulation of CCR4, CCL17 and CCL22 expression was detected in VCAT in comparison with SCAT (p<0.05). Using the parallel-plate flow chamber model, blockade of endothelial CCR4 function with the neutralizing antibody anti-CCR4 in morbidly obese patients significantly reduced leucocyte adhesiveness to dysfunctional endothelium, a key event in atherogenesis. Additionally, CCL17 and CCL22 increased activation of the ERK1/2 mitogen-activated protein kinase signalling pathway in human aortic endothelial cells, which was significantly reduced by CCR4 inhibition (p=0.016 and p<0.05). Conclusion: Based on these findings, pharmacological modulation of the CCR4 axis could represent a new therapeutic approach to prevent adipose tissue dysfunction in obesity.


Assuntos
Células Endoteliais , Obesidade Mórbida , Humanos , Adulto , Pessoa de Meia-Idade , Células Endoteliais/metabolismo , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Quimiocina CCL17/genética , Quimiocinas , Transdução de Sinais , Receptores de Quimiocinas/metabolismo , Quimiocina CCL22/genética
11.
Biomed J ; 46(6): 100588, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36925108

RESUMO

BACKGROUND: Enterotoxigenic Escherichia coli (ETEC) strains cause infectious diarrhea and colonize host intestine epithelia via surface-expressed colonization factors. Colonization factor antigen I (CFA/I), a prevalent ETEC colonization factor, is a vaccine target since antibodies directed to this fimbria can block ETEC adherence and prevent diarrhea. METHODS: Two recombinant antigens derived from CFA/I were investigated with a vaccine adjuvant system that displays soluble antigens on the surface of immunogenic liposomes. The first antigen, CfaEB, is a chimeric fusion protein comprising the minor (CfaE) and major (CfaB) subunits of CFA/I. The second, CfaEad, is the adhesin domain of CfaE. RESULTS: Owing to their His-tag, recombinant CfaEB and CfaEad, spontaneously bound upon admixture with nanoliposomes containing cobalt-porphyrin phospholipid (CoPoP), as well as a synthetic monophosphoryl lipid A (PHAD) adjuvant. Intramuscular immunization of mice with sub-microgram doses CfaEB or CfaEad admixed with CoPoP/PHAD liposomes elicited serum IgG and intestinal IgA antibodies. The smaller CfaEad antigen benefitted more from liposome display. Serum and intestine antibodies from mice immunized with liposome-displayed CfaEB or CfaEad recognized native CFA/I fimbria as evidenced by immunofluorescence and hemagglutination inhibition assays using the CFA/I-expressing H10407 ETEC strain. CONCLUSION: These data show that colonization factor-derived recombinant ETEC antigens exhibit immunogenicity when delivered in immunogenic particle-based formulations.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Animais , Camundongos , Lipossomos , Infecções por Escherichia coli/prevenção & controle , Diarreia , Adesinas Bacterianas , Antígenos de Bactérias
12.
J Neurosci ; 43(14): 2440-2459, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36849416

RESUMO

Local translation in neurons is partly mediated by the reactivation of stalled polysomes. Stalled polysomes may be enriched within the granule fraction, defined as the pellet of sucrose gradients used to separate polysomes from monosomes. The mechanism of how elongating ribosomes are reversibly stalled and unstalled on mRNAs is still unclear. In the present study, we characterize the ribosomes in the granule fraction using immunoblotting, cryogenic electron microscopy (cryo-EM), and ribosome profiling. We find that this fraction, isolated from 5-d-old rat brains of both sexes, is enriched in proteins implicated in stalled polysome function, such as the fragile X mental retardation protein (FMRP) and Up-frameshift mutation 1 homologue. Cryo-EM analysis of ribosomes in this fraction indicates they are stalled, mainly in the hybrid state. Ribosome profiling of this fraction reveals (1) an enrichment for footprint reads of mRNAs that interact with FMRPs and are associated with stalled polysomes, (2) an abundance of footprint reads derived from mRNAs of cytoskeletal proteins implicated in neuronal development, and (3) increased ribosome occupancy on mRNAs encoding RNA binding proteins. Compared with those usually found in ribosome profiling studies, the footprint reads were longer and were mapped to reproducible peaks in the mRNAs. These peaks were enriched in motifs previously associated with mRNAs cross-linked to FMRP in vivo, independently linking the ribosomes in the granule fraction to the ribosomes associated with FMRP in the cell. The data supports a model in which specific sequences in mRNAs act to stall ribosomes during translation elongation in neurons.SIGNIFICANCE STATEMENT Neurons send mRNAs to synapses in RNA granules, where they are not translated until an appropriate stimulus is given. Here, we characterize a granule fraction obtained from sucrose gradients and show that polysomes in this fraction are stalled on consensus sequences in a specific state of translational arrest with extended ribosome-protected fragments. This finding greatly increases our understanding of how neurons use specialized mechanisms to regulate translation and suggests that many studies on neuronal translation may need to be re-evaluated to include the large fraction of neuronal polysomes found in the pellet of sucrose gradients used to isolate polysomes.


Assuntos
Proteína do X Frágil de Retardo Mental , Ribossomos , Animais , Feminino , Masculino , Ratos , Grânulos de Ribonucleoproteínas Citoplasmáticas/metabolismo , Proteína do X Frágil de Retardo Mental/genética , Polirribossomos , Biossíntese de Proteínas , Ribossomos/metabolismo , RNA Mensageiro/metabolismo
13.
Animals (Basel) ; 12(23)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36496780

RESUMO

Mycobacteriosis is an important disease that affects captive and wild aquatic fish. Syngnathids are susceptible to infection by non-tuberculous mycobacteria. The aim of this study was to describe clinical signs, and macroscopic and histological lesions in 25 syngnathids and the molecular characterization of the causative mycobacteria. Clinical presentation ranged from sudden death to non-specific signs, including anorexia, poor body condition, weight loss and marked dyspnea with increased respiratory effort and rate. Gross lesions were mostly ulcers on the tail and small white nodules in the liver, coelomic cavity and inside the eye. The most affected organs were gills, liver, intestine and coelomic mesentery. Microscopic lesions consisted of areas of multifocal to diffuse granulomatous inflammation and bacterial emboli with numerous intralesional acid-fast bacilli. Epithelioid cells, multinucleated giant cells, lymphocytes and fibrous connective tissue, which are commonly observed in granulomatous inflammation, were not observed here. In the real-time PCR, M. fortuitum, M. chelonae and M. marinum common primers, Mycobacterium spp. were detected in 4, 7 and 14 individuals, respectively. In addition, this is the first description of mycobacteriosis found in Syngnathus acus.

14.
mBio ; 13(6): e0141322, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36286522

RESUMO

Clp proteases consist of a proteolytic, tetradecameric ClpP core and AAA+ Clp-ATPases. Streptomycetes, producers of a plethora of secondary metabolites, encode up to five different ClpP homologs, and the composition of their unusually complex Clp protease machinery has remained unsolved. Here, we report on the composition of the housekeeping Clp protease in Streptomyces, consisting of a heterotetradecameric core built of ClpP1, ClpP2, and the cognate Clp-ATPases ClpX, ClpC1, or ClpC2, all interacting with ClpP2 only. Antibiotic acyldepsipeptides (ADEP) dysregulate the Clp protease for unregulated proteolysis. We observed that ADEP binds Streptomyces ClpP1, but not ClpP2, thereby not only triggering the degradation of nonnative protein substrates but also accelerating Clp-ATPase-dependent proteolysis. The explanation is the concomitant binding of ADEP and Clp-ATPases to opposite sides of the ClpP1P2 barrel, hence revealing a third, so far unknown mechanism of ADEP action, i.e., the accelerated proteolysis of native protein substrates by the Clp protease. IMPORTANCE Clp proteases are antibiotic and anticancer drug targets. Composed of the proteolytic core ClpP and a regulatory Clp-ATPase, the protease machinery is important for protein homeostasis and regulatory proteolysis. The acyldepsipeptide antibiotic ADEP targets ClpP and has shown promise for treating multiresistant and persistent bacterial infections. The molecular mechanism of ADEP is multilayered. Here, we present a new way how ADEP can deregulate the Clp protease system. Clp-ATPases and ADEP bind to opposite sides of Streptomyces ClpP, accelerating the degradation of natural Clp protease substrates. We also demonstrate the composition of the major Streptomyces Clp protease complex, a heteromeric ClpP1P2 core with the Clp-ATPases ClpX, ClpC1, or ClpC2 exclusively bound to ClpP2, and the killing mechanism of ADEP in Streptomyces.


Assuntos
Streptomyces , Proteólise , Streptomyces/metabolismo , Endopeptidase Clp/metabolismo , Proteínas de Bactérias/metabolismo , Antibacterianos , ATPases Translocadoras de Prótons/metabolismo , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Peptídeo Hidrolases/metabolismo
15.
J Virol ; 96(19): e0100622, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36106872

RESUMO

Intranasal vaccination offers the potential advantage of needle-free prevention of respiratory pathogens such as influenza viruses with induction of mucosal immune responses. Optimal design of adjuvants and antigen delivery vehicles for intranasal delivery has not yet been well established. Here, we report that an adjuvant-containing nanoliposome antigen display system that converts soluble influenza hemagglutinin antigens into nanoparticles is effective for intranasal immunization. Intranasal delivery of nanoliposomes in mice delivers the particles to resident immune cells in the respiratory tract, inducing a mucosal response in the respiratory system as evidenced by nasal and lung localized IgA antibody production, while also producing systemic IgG antibodies. Intranasal vaccination with nanoliposome particles decorated with nanogram doses of hemagglutinin protected mice from homologous and heterologous H3N2 and H1N1 influenza virus challenge. IMPORTANCE A self-assembling influenza virus vaccine platform that seamlessly converts soluble antigens into nanoparticles is demonstrated with various H1N1 and H3N2 influenza antigens to protect mice against influenza virus challenge following intranasal vaccination. Mucosal immune responses following liposome delivery to lung antigen-presenting cells are demonstrated.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza , Imunidade nas Mucosas , Vacinas contra Influenza , Infecções por Orthomyxoviridae , Adjuvantes Imunológicos , Administração Intranasal , Animais , Anticorpos Antivirais/imunologia , Células Apresentadoras de Antígenos/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/administração & dosagem , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Lipossomos , Camundongos , Nanopartículas , Infecções por Orthomyxoviridae/prevenção & controle , Vacinação
16.
Entropy (Basel) ; 24(8)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-36010713

RESUMO

Predicting the values of a financial time series is mainly a function of its price history, which depends on several factors, internal and external. With this history, it is possible to build an ∊-machine for predicting the financial time series. This work proposes considering the influence of a financial series through the transfer of entropy when the values of the other financial series are known. A method is proposed that considers the transfer of entropy for breaking the ties that occur when calculating the prediction with the ∊-machine. This analysis is carried out using data from six financial series: two American, the S&P 500 and the Nasdaq; two Asian, the Hang Seng and the Nikkei 225; and two European, the CAC 40 and the DAX. This work shows that it is possible to influence the prediction of the closing value of a series if the value of the influencing series is known. This work showed that the series that transfer the most information through entropy transfer are the American S&P 500 and Nasdaq, followed by the European DAX and CAC 40, and finally the Asian Nikkei 225 and Hang Seng.

17.
Transl Oncol ; 19: 101390, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35290919

RESUMO

Irinotecan (IRI) loaded actively into PEGylated liposomes via a sucrosulfate gradient has been approved recently to treat advanced pancreatic cancer. In this study, a similar liposomal composition was developed that includes a low mole fraction (1 mol.%) of porphyrin-phospholipid (PoP), a photosensitizer that stably incorporates into liposomes, to confer light-triggered IRI release. IRI-loaded PoP liposomes containing ammonium sucrosulfate (ASOS) as a complexing agent were more stable in serum compared to liposomes employing the more conventional ammonium sulfate. Without irradiation, PoP IRI liposomes released less than 5% IRI during 8 h of incubation in bovine serum at 37 °C, but released over 90% of the drug within minutes of exposure to red light (665 nm) irradiation. A single treatment with IRI-PoP liposomes and light exposure (15 mg/kg IRI with 250 J/cm2) resulted in tumor eradication in mice bearing either MIA PaCa-2 tumors or low-passage patient-derived tumor xenografts that recapitulate characteristics of the clinical disease. Analogous monotherapies of IRI or photodynamic therapy were ineffective in controlling tumor growth. Enhanced drug uptake could be visualized within laser-treated tumors by direct in situ imaging of irinotecan. Biodistribution analysis of IRI, its active metabolite (SN-38), and major metabolite (SN-38 G) showed that laser treatment significantly increased tumor accumulation of all IRI-derived molecular species. A pharmacokinetic model that hypothesized tumor vasculature permeabilization as the primary reason underlying the increased drug deposition accounted for the enhanced drug influx into tumors.

18.
PLoS One ; 17(3): e0263671, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35275926

RESUMO

Novel therapeutic strategies are needed to control the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic. Here, we present a protocol to anchor the SARS-CoV-2 spike (S-)protein in the cytoplasmic membranes of erythrocyte liposomes. A surfactant was used to stabilize the S-protein's structure in the aqueous environment before insertion and to facilitate reconstitution of the S-proteins in the erythrocyte membranes. The insertion process was studied using coarse grained Molecular Dynamics (MD) simulations. Liposome formation and S-protein anchoring was studied by dynamic light scattering (DLS), ELV-protein co-sedimentation assays, fluorescent microcopy and cryo-TEM. The Erythro-VLPs (erythrocyte based virus like particles) have a well defined size of ∼200 nm and an average protein density on the outer membrane of up to ∼300 proteins/µm2. The correct insertion and functional conformation of the S-proteins was verified by dose-dependent binding to ACE-2 (angiotensin converting enzyme 2) in biolayer interferometry (BLI) assays. Seroconversion was observed in a pilot mouse trial after 14 days when administered intravenously, based on enzyme-linked immunosorbent assays (ELISA). This red blood cell based platform can open novel possibilities for therapeutics for the coronavirus disease (COVID-19) including variants, and other viruses in the future.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Membrana Eritrocítica , Simulação de Dinâmica Molecular , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus , Vacinas de Partículas Semelhantes a Vírus , Animais , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/química , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/farmacologia , Membrana Eritrocítica/química , Membrana Eritrocítica/imunologia , Feminino , Lipossomos , Camundongos , Projetos Piloto , Domínios Proteicos , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/farmacologia , Vacinas de Partículas Semelhantes a Vírus/química , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/farmacologia
19.
Rev Esp Salud Publica ; 962022 Mar 25.
Artigo em Espanhol | MEDLINE | ID: mdl-35332116

RESUMO

OBJECTIVE: Current literature is insufficient to determine the acceptability of self-sampling as a primary method for cervical cancer screening among women from a regular screening population. The aim of this study was to determine the acceptability of self-sampling among women in the Region of Murcia as a primary screening tool. METHODS: We performed a cross-sectional study between April-May 2021, in a regional sample of 247 women ages 35-65 years. All participants were contacted and completed a survey by telephone which included sociodemographic characteristics, knowledge and attitudes towards cancer screening, and self-sampling assessment. We conducted weighted statistical analysis including descriptive, bivariate and a multivariate logistic regression model to examine the associations between women's characteristics and their preference for self-sampling compared to clinician sampling. RESULTS: A total of 89.4% of participants reported at least one previous cytology in the last 5 years, 88.7% with a frequency equal to or less than 3 years. Eighty-one percent of women preferred self-sampling over clinical sampling as a primary screening method. Basal characteristics were unrelated to women's preference for self-sampling (P-adjusted≥0.05). Feasibility and reliability were the main concerns perceived in relation to self-sampling (23.3% and 14.8%, respectively). CONCLUSIONS: Acceptability of self-sampling was high among women in the Region of Murcia. Self-sampling in conjunction with an adequate educational strategy could be a suitable approach to consider in the cervical cancer screening program.


OBJETIVO: Actualmente existe poca evidencia publicada sobre la aceptabilidad de la autotoma como prueba inicial de cribado del cáncer de cérvix en una población de mujeres que acuden a cribado regularmente. El objetivo del estudio fue determinar la aceptabilidad de la autotoma en mujeres de la Región de Murcia (RM) como prueba primaria de cribado. METODOS: Estudio transversal mediante encuesta telefónica a una muestra de 247 mujeres entre 35-65 años de la RM entre abril-mayo de 2021. Se recogieron las características sociodemográficas, los conocimientos, actitudes frente a los cribados de cáncer y valoración de la autotoma. Se realizó un análisis ponderado descriptivo, bivariante y regresión logística multivariante para determinar las características de las participantes relacionadas con su preferencia por la autotoma frente a la toma realizada por un profesional sanitario. RESULTADOS: El 89,4% de las mujeres refirieron realizarse alguna citología en los últimos 5 años, el 88,7% de ellas con una frecuencia ≤3 años. El 81% de las mujeres prefirieron la autotoma como prueba primaria de cribado para la detección del cáncer de cérvix. No se detectaron características relacionadas con la preferencia de la autotoma frente a la toma por un profesional sanitario (P-ajustado≥0,05). Los principales inconvenientes valorados de la autotoma fueron la factibilidad (23,3%) y fiabilidad de la prueba (14,8%). CONCLUSIONES: La aceptabilidad de la autotoma fue elevada entre las mujeres encuestadas de la RM. Sería conveniente valorar este método junto a una estrategia adecuada de educación a las mujeres dentro del programa de prevención del cáncer de cérvix.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Adulto , Idoso , Estudos Transversais , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/diagnóstico , Reprodutibilidade dos Testes , Autocuidado/métodos , Espanha , Neoplasias do Colo do Útero/diagnóstico
20.
PLoS One ; 17(3): e0264713, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35298483

RESUMO

In most big cities, public transports are enclosed and crowded spaces. Therefore, they are considered as one of the most important triggers of COVID-19 spread. Most of the existing research related to the mobility of people and COVID-19 spread is focused on investigating highly frequented paths by analyzing data collected from mobile devices, which mainly refer to geo-positioning records. In contrast, this paper tackles the problem by studying mass mobility. The relations between daily mobility on public transport (subway or metro) in three big cities and mortality due to COVID-19 are investigated. Data collected for these purposes come from official sources, such as the web pages of the cities' local governments. To provide a systematic framework, we applied the IBM Foundational Methodology for Data Science to the epidemiological domain of this paper. Our analysis consists of moving averages with a moving window equal to seven days so as to avoid bias due to weekly tendencies. Among the main findings of this work are: a) New York City and Madrid show similar distribution on studied variables, which resemble a Gauss bell, in contrast to Mexico City, and b) Non-pharmaceutical interventions don't bring immediate results, and reductions to the number of deaths due to COVID are observed after a certain number of days. This paper yields partial evidence for assessing the effectiveness of public policies in mitigating the COVID-19 pandemic.


Assuntos
COVID-19/mortalidade , Meios de Transporte , Adulto , COVID-19/epidemiologia , Cidades/epidemiologia , Cidades/estatística & dados numéricos , Ciência de Dados/métodos , Modelos Epidemiológicos , Humanos , México/epidemiologia , Cidade de Nova Iorque/epidemiologia , Espanha/epidemiologia , Meios de Transporte/métodos , Meios de Transporte/estatística & dados numéricos
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