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1.
Nature ; 598(7882): 662-666, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34616044

RESUMEN

The availability of L-arginine in tumours is a key determinant of an efficient anti-tumour T cell response1-4. Consequently, increases of typically low L-arginine concentrations within the tumour may greatly potentiate the anti-tumour responses of immune checkpoint inhibitors, such as programmed death-ligand 1 (PD-L1)-blocking antibodies5. However, currently no means are available to locally increase intratumoural L-arginine levels. Here we used a synthetic biology approach to develop an engineered probiotic Escherichia coli Nissle 1917 strain that colonizes tumours and continuously converts ammonia, a metabolic waste product that accumulates in tumours6, to L-arginine. Colonization of tumours with these bacteria increased intratumoural L-arginine concentrations, increased the number of tumour-infiltrating T cells and had marked synergistic effects with PD-L1 blocking antibodies in the clearance of tumours. The anti-tumour effect of these bacteria was mediated by L-arginine and was dependent on T cells. These results show that engineered microbial therapies enable metabolic modulation of the tumour microenvironment leading to enhanced efficacy of immunotherapies.


Asunto(s)
Inmunoterapia/métodos , Ingeniería Metabólica , Microorganismos Modificados Genéticamente , Neoplasias Experimentales/terapia , Traslado Adoptivo , Animales , Arginina/metabolismo , Antígeno B7-H1/antagonistas & inhibidores , Línea Celular Tumoral , Escherichia coli , Femenino , Linfocitos Infiltrantes de Tumor/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/microbiología , Probióticos , Proteoma , Biología Sintética , Linfocitos T/inmunología , Microambiente Tumoral/inmunología
2.
N Engl J Med ; 388(16): 1465-1477, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37018468

RESUMEN

BACKGROUND: Respiratory syncytial virus (RSV) infection causes considerable illness in older adults. The efficacy and safety of an investigational bivalent RSV prefusion F protein-based (RSVpreF) vaccine in this population are unknown. METHODS: In this ongoing, phase 3 trial, we randomly assigned, in a 1:1 ratio, adults (≥60 years of age) to receive a single intramuscular injection of RSVpreF vaccine at a dose of 120 µg (RSV subgroups A and B, 60 µg each) or placebo. The two primary end points were vaccine efficacy against seasonal RSV-associated lower respiratory tract illness with at least two or at least three signs or symptoms. The secondary end point was vaccine efficacy against RSV-associated acute respiratory illness. RESULTS: At the interim analysis (data-cutoff date, July 14, 2022), 34,284 participants had received RSVpreF vaccine (17,215 participants) or placebo (17,069 participants). RSV-associated lower respiratory tract illness with at least two signs or symptoms occurred in 11 participants in the vaccine group (1.19 cases per 1000 person-years of observation) and 33 participants in the placebo group (3.58 cases per 1000 person-years of observation) (vaccine efficacy, 66.7%; 96.66% confidence interval [CI], 28.8 to 85.8); 2 cases (0.22 cases per 1000 person-years of observation) and 14 cases (1.52 cases per 1000 person-years of observation), respectively, occurred with at least three signs or symptoms (vaccine efficacy, 85.7%; 96.66% CI, 32.0 to 98.7). RSV-associated acute respiratory illness occurred in 22 participants in the vaccine group (2.38 cases per 1000 person-years of observation) and 58 participants in the placebo group (6.30 cases per 1000 person-years of observation) (vaccine efficacy, 62.1%; 95% CI, 37.1 to 77.9). The incidence of local reactions was higher with vaccine (12%) than with placebo (7%); the incidences of systemic events were similar (27% and 26%, respectively). Similar rates of adverse events through 1 month after injection were reported (vaccine, 9.0%; placebo, 8.5%), with 1.4% and 1.0%, respectively, considered by the investigators to be injection-related. Severe or life-threatening adverse events were reported in 0.5% of vaccine recipients and 0.4% of placebo recipients. Serious adverse events were reported in 2.3% of participants in each group through the data-cutoff date. CONCLUSIONS: RSVpreF vaccine prevented RSV-associated lower respiratory tract illness and RSV-associated acute respiratory illness in adults (≥60 years of age), without evident safety concerns. (Funded by Pfizer; RENOIR ClinicalTrials.gov number, NCT05035212; EudraCT number, 2021-003693-31.).


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Vacunas contra Virus Sincitial Respiratorio , Infecciones del Sistema Respiratorio , Anciano , Humanos , Anticuerpos Antivirales , Método Doble Ciego , Infecciones por Virus Sincitial Respiratorio/diagnóstico , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/prevención & control , Vacunas contra Virus Sincitial Respiratorio/administración & dosificación , Vacunas contra Virus Sincitial Respiratorio/efectos adversos , Vacunas contra Virus Sincitial Respiratorio/uso terapéutico , Vacunas Combinadas/administración & dosificación , Vacunas Combinadas/efectos adversos , Vacunas Combinadas/uso terapéutico , Eficacia de las Vacunas , Resultado del Tratamiento , Persona de Mediana Edad , Inyecciones Intramusculares , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/prevención & control
3.
N Engl J Med ; 388(16): 1451-1464, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37018474

RESUMEN

BACKGROUND: Whether vaccination during pregnancy could reduce the burden of respiratory syncytial virus (RSV)-associated lower respiratory tract illness in newborns and infants is uncertain. METHODS: In this phase 3, double-blind trial conducted in 18 countries, we randomly assigned, in a 1:1 ratio, pregnant women at 24 through 36 weeks' gestation to receive a single intramuscular injection of 120 µg of a bivalent RSV prefusion F protein-based (RSVpreF) vaccine or placebo. The two primary efficacy end points were medically attended severe RSV-associated lower respiratory tract illness and medically attended RSV-associated lower respiratory tract illness in infants within 90, 120, 150, and 180 days after birth. A lower boundary of the confidence interval for vaccine efficacy (99.5% confidence interval [CI] at 90 days; 97.58% CI at later intervals) greater than 20% was considered to meet the success criterion for vaccine efficacy with respect to the primary end points. RESULTS: At this prespecified interim analysis, the success criterion for vaccine efficacy was met with respect to one primary end point. Overall, 3682 maternal participants received vaccine and 3676 received placebo; 3570 and 3558 infants, respectively, were evaluated. Medically attended severe lower respiratory tract illness occurred within 90 days after birth in 6 infants of women in the vaccine group and 33 infants of women in the placebo group (vaccine efficacy, 81.8%; 99.5% CI, 40.6 to 96.3); 19 cases and 62 cases, respectively, occurred within 180 days after birth (vaccine efficacy, 69.4%; 97.58% CI, 44.3 to 84.1). Medically attended RSV-associated lower respiratory tract illness occurred within 90 days after birth in 24 infants of women in the vaccine group and 56 infants of women in the placebo group (vaccine efficacy, 57.1%; 99.5% CI, 14.7 to 79.8); these results did not meet the statistical success criterion. No safety signals were detected in maternal participants or in infants and toddlers up to 24 months of age. The incidences of adverse events reported within 1 month after injection or within 1 month after birth were similar in the vaccine group (13.8% of women and 37.1% of infants) and the placebo group (13.1% and 34.5%, respectively). CONCLUSIONS: RSVpreF vaccine administered during pregnancy was effective against medically attended severe RSV-associated lower respiratory tract illness in infants, and no safety concerns were identified. (Funded by Pfizer; MATISSE ClinicalTrials.gov number, NCT04424316.).


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Vacunas contra Virus Sincitial Respiratorio , Infecciones del Sistema Respiratorio , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , Anticuerpos Antivirales , Enfermedades Transmisibles/terapia , Método Doble Ciego , Inyecciones Intramusculares , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/prevención & control , Vacunas contra Virus Sincitial Respiratorio/administración & dosificación , Vacunas contra Virus Sincitial Respiratorio/efectos adversos , Vacunas contra Virus Sincitial Respiratorio/uso terapéutico , Virus Sincitiales Respiratorios , Resultado del Tratamiento , Vacunación/efectos adversos , Vacunación/métodos , Eficacia de las Vacunas , Vacunas Combinadas/administración & dosificación , Vacunas Combinadas/efectos adversos , Vacunas Combinadas/uso terapéutico , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/prevención & control
4.
Nature ; 583(7814): 48-54, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32572207

RESUMEN

Observation of the neutrinoless double ß decay is the only practical way to establish that neutrinos are their own antiparticles1. Because of the small masses of neutrinos, the lifetime of neutrinoless double ß decay is expected to be at least ten orders of magnitude greater than the typical lifetimes of natural radioactive chains, which can mimic the experimental signature of neutrinoless double ß decay2. The most robust identification of neutrinoless double ß decay requires the definition of a signature signal-such as the observation of the daughter atom in the decay-that cannot be generated by radioactive backgrounds, as well as excellent energy resolution. In particular, the neutrinoless double ß decay of 136Xe could be established by detecting the daughter atom, 136Ba2+, in its doubly ionized state3-8. Here we demonstrate an important step towards a 'barium-tagging' experiment, which identifies double ß decay through the detection of a single Ba2+ ion. We propose a fluorescent bicolour indicator as the core of a sensor that can detect single Ba2+ ions in a high-pressure xenon gas detector. In a sensor made of a monolayer of such indicators, the Ba2+ dication would be captured by one of the molecules and generate a Ba2+-coordinated species with distinct photophysical properties. The presence of such a single Ba2+-coordinated indicator would be revealed by its response to repeated interrogation with a laser system, enabling the development of a sensor able to detect single Ba2+ ions in high-pressure xenon gas detectors for barium-tagging experiments.

5.
Proc Natl Acad Sci U S A ; 120(50): e2312242120, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38055736

RESUMEN

The evolution of cooperation is a major question in the biological and behavioral sciences. While most theoretical studies model cooperation in the context of an isolated interaction (e.g., a Prisoner's Dilemma), humans live in heterogeneous social environments, characterized by large variations in fitness interdependence-the extent to which one's fitness is affected by others. Theoretical and experimental work indicates that humans can infer, and respond to, variations in interdependence. In a heterogeneous ancestral environment, these psychological mechanisms to infer fitness interdependence could have provided a selective advantage, allowing individuals to maximize their fitness by deciding when and with whom to cooperate. Yet, to date, the link between cognitive inference, variation in fitness interdependence, and cooperation remains unclear. Here we introduce a theoretical framework to study the evolution of inference and cooperation in heterogeneous social environments, where individuals experience interactions with varying levels of corresponding interests. Using a combination of evolutionary game theory and agent-based modeling, we model the evolution of adaptive agents, who incur a cost to infer interdependence, in populations of fixed-behavior agents who always cooperate or defect. Our results indicate that natural selection could promote the evolution of psychological mechanisms to infer fitness interdependence, provided that there is enough variation in fitness interdependence to offset the cost of inference. Under certain conditions, the fixation of adaptive agents results in higher levels of cooperation. This depends crucially on the type of inference performed and the features of the interdependence landscape.


Asunto(s)
Evolución Biológica , Conducta Cooperativa , Humanos , Teoría del Juego , Modelos Teóricos , Selección Genética
6.
N Engl J Med ; 386(22): 2084-2096, 2022 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-35507508

RESUMEN

BACKGROUND: Coronavirus-like particles (CoVLP) that are produced in plants and display the prefusion spike glycoprotein of the original strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are combined with an adjuvant (Adjuvant System 03 [AS03]) to form the candidate vaccine. METHODS: In this phase 3, multinational, randomized, placebo-controlled trial conducted at 85 centers, we assigned adults (≥18 years of age) in a 1:1 ratio to receive two intramuscular injections of the CoVLP+AS03 vaccine or placebo 21 days apart. The primary objective of the trial was to determine the efficacy of the CoVLP+AS03 vaccine in preventing symptomatic coronavirus disease 2019 (Covid-19) beginning at least 7 days after the second injection, with the analysis performed after the detection of at least 160 cases. RESULTS: A total of 24,141 volunteers participated in the trial; the median age of the participants was 29 years. Covid-19 was confirmed by polymerase-chain-reaction assay in 165 participants in the intention-to-treat population; all viral samples that could be sequenced contained variants of the original strain. Vaccine efficacy was 69.5% (95% confidence interval [CI], 56.7 to 78.8) against any symptomatic Covid-19 caused by five variants that were identified by sequencing. In a post hoc analysis, vaccine efficacy was 78.8% (95% CI, 55.8 to 90.8) against moderate-to-severe disease and 74.0% (95% CI, 62.1 to 82.5) among the participants who were seronegative at baseline. No severe cases of Covid-19 occurred in the vaccine group, in which the median viral load for breakthrough cases was lower than that in the placebo group by a factor of more than 100. Solicited adverse events were mostly mild or moderate and transient and were more frequent in the vaccine group than in the placebo group; local adverse events occurred in 92.3% and 45.5% of participants, respectively, and systemic adverse events in 87.3% and 65.0%. The incidence of unsolicited adverse events was similar in the two groups up to 21 days after each dose (22.7% and 20.4%) and from day 43 through day 201 (4.2% and 4.0%). CONCLUSIONS: The CoVLP+AS03 vaccine was effective in preventing Covid-19 caused by a spectrum of variants, with efficacy ranging from 69.5% against symptomatic infection to 78.8% against moderate-to-severe disease. (Funded by Medicago; ClinicalTrials.gov number, NCT04636697.).


Asunto(s)
Adyuvantes de Vacunas , Vacunas contra la COVID-19 , COVID-19 , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/efectos adversos , Adyuvantes Inmunológicos/uso terapéutico , Adyuvantes de Vacunas/administración & dosificación , Adyuvantes de Vacunas/efectos adversos , Adyuvantes de Vacunas/uso terapéutico , Adulto , Anticuerpos Antivirales , COVID-19/genética , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/uso terapéutico , Método Doble Ciego , Humanos , Inyecciones Intramusculares , SARS-CoV-2/genética , Vacunación
7.
N Engl J Med ; 385(19): 1761-1773, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34525277

RESUMEN

BACKGROUND: BNT162b2 is a lipid nanoparticle-formulated, nucleoside-modified RNA vaccine encoding a prefusion-stabilized, membrane-anchored severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) full-length spike protein. BNT162b2 is highly efficacious against coronavirus disease 2019 (Covid-19) and is currently approved, conditionally approved, or authorized for emergency use worldwide. At the time of initial authorization, data beyond 2 months after vaccination were unavailable. METHODS: In an ongoing, placebo-controlled, observer-blinded, multinational, pivotal efficacy trial, we randomly assigned 44,165 participants 16 years of age or older and 2264 participants 12 to 15 years of age to receive two 30-µg doses, at 21 days apart, of BNT162b2 or placebo. The trial end points were vaccine efficacy against laboratory-confirmed Covid-19 and safety, which were both evaluated through 6 months after vaccination. RESULTS: BNT162b2 continued to be safe and have an acceptable adverse-event profile. Few participants had adverse events leading to withdrawal from the trial. Vaccine efficacy against Covid-19 was 91.3% (95% confidence interval [CI], 89.0 to 93.2) through 6 months of follow-up among the participants without evidence of previous SARS-CoV-2 infection who could be evaluated. There was a gradual decline in vaccine efficacy. Vaccine efficacy of 86 to 100% was seen across countries and in populations with diverse ages, sexes, race or ethnic groups, and risk factors for Covid-19 among participants without evidence of previous infection with SARS-CoV-2. Vaccine efficacy against severe disease was 96.7% (95% CI, 80.3 to 99.9). In South Africa, where the SARS-CoV-2 variant of concern B.1.351 (or beta) was predominant, a vaccine efficacy of 100% (95% CI, 53.5 to 100) was observed. CONCLUSIONS: Through 6 months of follow-up and despite a gradual decline in vaccine efficacy, BNT162b2 had a favorable safety profile and was highly efficacious in preventing Covid-19. (Funded by BioNTech and Pfizer; ClinicalTrials.gov number, NCT04368728.).


Asunto(s)
Vacunas contra la COVID-19 , COVID-19/prevención & control , Inmunogenicidad Vacunal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/análisis , Vacuna BNT162 , COVID-19/epidemiología , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/inmunología , Niño , Femenino , Estudios de Seguimiento , Humanos , Inmunización Secundaria , Incidencia , Masculino , Persona de Mediana Edad , SARS-CoV-2/inmunología , Método Simple Ciego , Resultado del Tratamiento , Adulto Joven
8.
Mol Reprod Dev ; 91(1): e23735, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38282317

RESUMEN

Boar seminal plasma (SP) proteins were associated with differences on sperm resistance to cooling at 17°C. However, information about seminal plasma proteins in boars classified by capacity of semen preservation and in vivo fertility remains lacking. Thus, the objective was to evaluate the SP proteome in boars classified by capacity of semen preservation and putative biomarkers for fertility. The ejaculates from high-preservation (HP) showed higher progressive motility during all 5 days than the low-preservation (LP) boars. There was no difference for farrowing rate between ejaculates from LP (89.7%) and HP boars (88.4%). The LP boars presented lower total piglets born (14.0 ± 0.2) than HP (14.8 ± 0.2; p < 0.01). A total of 257 proteins were identified, where 184 were present in both classes of boar, and 41 and 32 were identified only in LP and HP boars, respectively. Nine proteins were differently expressed: five were more abundant in HP (SPMI, ZPBP1, FN1, HPX, and C3) and four in LP boars (B2M, COL1A1, NKX3-2, and MPZL1). The HP boars had an increased abundance of SP proteins related to sperm resistance and fecundation process which explains the better TPB. LP boars had a higher abundance of SP proteins associated with impaired spermatogenesis.


Asunto(s)
Preservación de Semen , Semen , Porcinos , Animales , Masculino , Semen/metabolismo , Preservación de Semen/veterinaria , Proteómica , Inseminación Artificial , Espermatozoides , Fertilidad , Análisis de Semen , Proteínas de Plasma Seminal/metabolismo , Motilidad Espermática
9.
Org Biomol Chem ; 22(9): 1800-1811, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38328903

RESUMEN

Dehydration of alcohols in the presence of copper(II) sulfate has been analyzed computationally. Density functional theory (DFT) calculations on selected alcohols indicate that this reaction can take place via two possible mechanisms: (a) concerted - although asynchronous - type II dyotropic reactions, or (b) stepwise E1-like processes, in which cleavage of the C-O bond occurs in the first step, followed by syn proton elimination. Our calculations show the relationship between the initial alcohol structure and the preferred mechanism, which is a type II dyotropic reaction for primary alcohols, whereas a stepwise process is the favored one when stable carbocation intermediates are energetically accessible. The dehydration of dehydrolinalool (2,7-dimethyl-6-en-1-yn-3-ol, DHL) to yield different alkenes of interest in the fragrance industry is discussed as a case study of its regiochemistry.

10.
Phys Chem Chem Phys ; 26(28): 19369-19379, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38967480

RESUMEN

Quantum spin liquids (QSLs) have become prominent materials of interest in the pursuit of fault-tolerant materials for quantum computing applications. This is due to the fact that these materials are theorized to host an interesting variety of quantum phenomena such as quasi-particles that may behave as anyons as a result of the high entangled nature of the spin states within the systems. Computing the electronic and magnetic properties of these materials is necessary in order to understand the underlying interactions of the materials. In this paper, the structural, electronic, and magnetic properties including lattice parameters, bandgap, Heisenberg coupling constants, and Curie temperatures for α-RuCl3, a promising candidate for the Kitaev QSL model, are computed using periodic density functional theory. Furthermore, various parameters of the calculations (i.e. functional choice, basis set, k-point density, and Hubbard correction) are varied in order to determine what effect, if any, the computational setup has on the computed properties. The results of this study indicate that PBE functional with Hubbard corrections of 1.5-2.5 eV with a k-point density of 3.0 points per Å-1 appear to be the best parameters to compute Heisenberg coupling constants for α-RuCl3. These parameters with the addition of spin orbit coupling works well for computing Curie temperatures for α-RuCl3. Distinct differences are noted in the computations of the bulk structure vs. monolayer structures, indicating that interactions between the layers play a role in the material properties and changes to the inter-layer spacing may result in interesting and unique magnetic properties that require further investigation.

11.
Nature ; 555(7695): 242-245, 2018 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-29516999

RESUMEN

Indirect reciprocity is the most elaborate and cognitively demanding of all known cooperation mechanisms, and is the most specifically human because it involves reputation and status. By helping someone, individuals may increase their reputation, which may change the predisposition of others to help them in future. The revision of an individual's reputation depends on the social norms that establish what characterizes a good or bad action and thus provide a basis for morality. Norms based on indirect reciprocity are often sufficiently complex that an individual's ability to follow subjective rules becomes important, even in models that disregard the past reputations of individuals, and reduce reputations to either 'good' or 'bad' and actions to binary decisions. Here we include past reputations in such a model and identify the key pattern in the associated norms that promotes cooperation. Of the norms that comply with this pattern, the one that leads to maximal cooperation (greater than 90 per cent) with minimum complexity does not discriminate on the basis of past reputation; the relative performance of this norm is particularly evident when we consider a 'complexity cost' in the decision process. This combination of high cooperation and low complexity suggests that simple moral principles can elicit cooperation even in complex environments.


Asunto(s)
Evolución Biológica , Conducta Cooperativa , Normas Sociales , Altruismo , Humanos , Modelos Psicológicos , Principios Morales
12.
BMC Public Health ; 24(1): 427, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38336643

RESUMEN

BACKGROUND: Information is scarce regarding the economic burden of respiratory syncytial virus (RSV) disease in low-resource settings. This study aimed to estimate the cost per episode of hospital admissions due to RSV severe disease in Argentina. METHODS: This is a prospective cohort study that collected information regarding 256 infants under 12 months of age with acute lower respiratory tract infection (ALRTI) due to RSV in two public hospitals of Buenos Aires between 2014 and 2016. Information on healthcare resource use was collected from the patient's report and its associated costs were estimated based on the financial database and account records of the hospitals. We estimated the total cost per hospitalization due to RSV using the health system perspective. The costs were estimated in US dollars as of December 2022 (1 US dollar = 170 Argentine pesos). RESULTS: The mean costs per RSV hospitalization in infants was US$587.79 (95% confidence interval [CI] $535.24 - $640.33). The mean costs associated with pediatric intensive care unit (PICU) admission more than doubled from those at regular pediatric wards ($1,556.81 [95% CI $512.21 - $2,601.40] versus $556.53 [95% CI $514.59 - $598.48]). CONCLUSIONS: This study shows the direct economic impact of acute severe RSV infection on the public health system in Argentina. The estimates obtained from this study could be used to inform cost-effectiveness analyses of new preventive RSV interventions being developed.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Lactante , Humanos , Niño , Estudios Prospectivos , Argentina/epidemiología , Infecciones por Virus Sincitial Respiratorio/epidemiología , Hospitalización , Infecciones del Sistema Respiratorio/epidemiología , Costo de Enfermedad
13.
Eur Spine J ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717495

RESUMEN

PURPOSE: To conduct an independent assessment of inter- and intraobserver agreement for the META score as a tool for differentiating osteoporotic vertebral fractures and multiple myeloma vertebral fractures. METHODS: This is a retrospective observational study. The magnetic resonance imaging analysis was made by two independent spinal surgeons. We designated a Subjective assessment, in which the surgeon should establish a diagnostic classification for each vertebral fracture based on personal experience: secondary to osteoporosis, categorized as a benign vertebral fracture (BVF), or attributed to multiple myeloma, categorized a malign vertebral fracture (MVF). After a 90-day interval, both surgeons repeated the evaluations. For the next step, the observers should establish a diagnosis between BVF and MVF according to the META score system, and both observers repeated the evaluations after a 90-day interval. The intra and interobserver reliability of the Subjective evaluation was studied using the kappa (κ) test. Then, the META evaluations were paralleled using the intraclass correlation coefficient (ICC). RESULTS: A total of 220 patients who had the potential to participate in the study were initially enrolled, but after applying the exclusion criteria, 44 patients were included. Thirty-three patients had BVF, and 12 patients presented MVF. Interobserver agreement for both Subjective evaluations moments (initial and 90-days interval) found a slight agreement for both moments (0.35 and 0.40 respectively). Kappa test for both META evaluations moments (initial and 90-days interval) found a moderate interobserver agreement for both moments (0.54 and 0.48 respectively). It was observed that the ICC calculated for the Initial evaluation using META score was 0.680 and that in the 90-days interval was 0.726, indicating regular to good agreement. Kappa test for intraobserver agreements for the Subjective evaluation presented moderate agreement for both Surgeons. On the other side, Kappa test for intraobserver agreements for the META evaluation presented substantial agreement for both Surgeons. The Intraclass Correlation Coefficient of the META score found presented an almost perfect agreement for both Surgeons. CONCLUSION: Intra and interobserver agreement for both surgeons were unsatisfactory. The lack of consistent reproducibility by the same observer discourages and disfavors the routine use of the META score in clinical decision making, when potentially cases of multiple myeloma may be present.

14.
Proc Natl Acad Sci U S A ; 118(50)2021 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-34876508

RESUMEN

The level of antagonism between political groups has risen in the past years. Supporters of a given party increasingly dislike members of the opposing group and avoid intergroup interactions, leading to homophilic social networks. While new connections offline are driven largely by human decisions, new connections on online social platforms are intermediated by link recommendation algorithms, e.g., "People you may know" or "Whom to follow" suggestions. The long-term impacts of link recommendation in polarization are unclear, particularly as exposure to opposing viewpoints has a dual effect: Connections with out-group members can lead to opinion convergence and prevent group polarization or further separate opinions. Here, we provide a complex adaptive-systems perspective on the effects of link recommendation algorithms. While several models justify polarization through rewiring based on opinion similarity, here we explain it through rewiring grounded in structural similarity-defined as similarity based on network properties. We observe that preferentially establishing links with structurally similar nodes (i.e., sharing many neighbors) results in network topologies that are amenable to opinion polarization. Hence, polarization occurs not because of a desire to shield oneself from disagreeable attitudes but, instead, due to the creation of inadvertent echo chambers. When networks are composed of nodes that react differently to out-group contacts, either converging or polarizing, we find that connecting structurally dissimilar nodes moderates opinions. Overall, our study sheds light on the impacts of social-network algorithms and unveils avenues to steer dynamics of radicalization and polarization in online social networks.

15.
PLoS Genet ; 17(11): e1009883, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34735433

RESUMEN

Spousal comparisons have been proposed as a design that can both reduce confounding and estimate effects of the shared adulthood environment. However, assortative mating, the process by which individuals select phenotypically (dis)similar mates, could distort associations when comparing spouses. We evaluated the use of spousal comparisons, as in the within-spouse pair (WSP) model, for aetiological research such as genetic association studies. We demonstrated that the WSP model can reduce confounding but may be susceptible to collider bias arising from conditioning on assorted spouse pairs. Analyses using UK Biobank spouse pairs found that WSP genetic association estimates were smaller than estimates from random pairs for height, educational attainment, and BMI variants. Within-sibling pair estimates, robust to demographic and parental effects, were also smaller than random pair estimates for height and educational attainment, but not for BMI. WSP models, like other within-family models, may reduce confounding from demographic factors in genetic association estimates, and so could be useful for triangulating evidence across study designs to assess the robustness of findings. However, WSP estimates should be interpreted with caution due to potential collider bias.


Asunto(s)
Conducta Sexual , Adulto , Índice de Masa Corporal , Estudios de Cohortes , Femenino , Humanos , Masculino , Esposos , Reino Unido
16.
J Oral Rehabil ; 51(8): 1521-1529, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38717007

RESUMEN

BACKGROUND: Current clinical approaches to regenerate temporomandibular joint (TMJ) articulating cartilage defects only treat the symptoms (i.e. pain and dysfunction) and do not seek to restore joint integrity for long-term relief. Therefore, we investigated a novel self-assembling tissue-engineered cartilage to overcome this significant clinical issue for TMJ regenerative purposes. OBJECTIVES: Examine the maturation of dynamic self-regenerating cartilage (dSRC) using auricular chondrocytes and evaluate a novel combinatorial approach with fractional laser treatment and dSRC implantation for TMJ cartilage repair. MATERIALS AND METHODS: A suspension of 107 freshly harvested rabbit ear chondrocytes was cultured under a continuous reciprocating motion to form the dSRC. After 2, 4 and 8 weeks of culture, dSRC samples were stained with H&E, Safranin-O and Toluidine Blue. Immunohistochemistry (IHC) was performed for collagens type I and II. Channels (300-500 µm diameter and 1.2-1.5 mm depth) were created in six freshly harvested condyles using a fractional Erbium laser. Two groups were tested: dSRC in a laser-ablated lesion (experimental) and an empty laser-ablated channel (control). TMJ condyles were cultured for up to 8 weeks and analysed as described above. RESULTS: H&E staining showed a high cell density in dSRC compared to native cartilage. All dSRC groups demonstrated intense Safranin-O staining, indicating high glycosaminoglycan (GAG) production and intense Toluidine Blue staining showed high proteoglycan content. IHC confirmed that dSRC consisted predominantly of collagen type II. The experimental group showed improved cartilage repair at both time points compared to the empty channels. CONCLUSION: dSRC viability and successful matrix formation were demonstrated in vitro. The combination of fractional laser ablation and dSRC implantation enhanced cartilage repair.


Asunto(s)
Cartílago Articular , Condrocitos , Regeneración , Articulación Temporomandibular , Ingeniería de Tejidos , Animales , Conejos , Condrocitos/trasplante , Ingeniería de Tejidos/métodos , Articulación Temporomandibular/cirugía , Articulación Temporomandibular/patología , Regeneración/fisiología , Cartílago Articular/cirugía , Cartílago Articular/patología , Trastornos de la Articulación Temporomandibular/cirugía , Trastornos de la Articulación Temporomandibular/fisiopatología , Trastornos de la Articulación Temporomandibular/terapia , Células Cultivadas , Cartílago Auricular/fisiología , Técnicas In Vitro
17.
J Oral Rehabil ; 51(2): 394-403, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37830126

RESUMEN

BACKGROUND: In the last decade, tissue-engineering strategies for regenerating the temporomandibular joint (TMJ) have been investigated. This may be a promising strategy for the minimally invasive restoration of joint integrity. OBJECTIVES: To evaluate whether dental pulp stem cells (DPSCs) loaded in a light-occured hydrogel made of gelatin methacryloyl (GelMA) enhance the regeneration of osteochondral defects in the rabbit TMJ. MATERIALS AND METHODS: Defects were filled with GelMA alone (control group; n = 4) or filled with GelMA loaded with rabbit DPSCs (experimental group; n = 4), In one group, the TMJ capsule was opened without creating a defect (sham group; n = 2). The following micro-CT parameters were analysed: bone volume to total volume ratio (BV/TV%) and bone mineral density (BMD). Histological evaluation was performed to assess cartilage regeneration features. A semi-quantitative scoring system was also used to evaluate the defects. RESULTS: All groups had no statistical difference regarding the micro-CT parameters. The highest mean healing score was found for the experimental group. After 4 weeks, there were no signs of hydrogel in either group or no signs of inflammation in the adjacent tissues. The tissue formed in the defect was dense fibrous connective tissue. CONCLUSION: Adding DPSCs to GelMA did not provide a regenerative enhancement in TMJ osteochondral defects. This resulted in similar micro-CT parameters after 4 weeks of healing, with improved signs of subchondral bone regeneration but no cartilage regeneration.


Asunto(s)
Pulpa Dental , Hidrogeles , Animales , Conejos , Articulación Temporomandibular , Ingeniería de Tejidos/métodos , Células Madre
18.
J Environ Manage ; 351: 119872, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38157579

RESUMEN

Controlled release of active ingredients are important for drug delivery and more recently environmental applications including modulated dosing of chemical and biological controls. This study demonstrates the importance of investigating various material science factors that can influence the diffusion rates of alginate beads to improve and tune their performance for marine environmental applications. This investigation aimed to design a rational workflow to aid in leveraging alginate bead use as a carrier matrix for releasing a specific active agent into water. Experiments were conducted to focus on the narrow a large list of relevant material formulation parameters, which included chitosan molecular weight, chitosan concentration, calcium concentration, drop height, and bead size. Once the most relevant material preparation methods were screened, a more robust statistic Design of Experiments approach was performed and results determined the important (and unimportant) factors for increasing dye release kinetics in marine water. The process was further streamlined by narrowing the critical experimental factors to a three-level based on the prior analysis: chitosan MW, chitosan concentration, and bead size. Analysis of the collected data indicated that while chitosan MW had a negligible impact (Fstatistic = 0.22), bead size (Fstatistic = 60.33) significantly influenced the diffusion rates based on surface area. However, chitosan MW had minor effects where lower chitosan MW enabled higher product release rates. This case investigation was a novel application of the design of experiment approach towards environmental applications to understand differences in release rates to marine waters for the first time and the workflow provided also serve as the basis for researchers to optimize other environmental applications requiring optimization when it is unknown how a large number of formulation variables will impact performance in different environmental scenarios.


Asunto(s)
Quitosano , Quitosano/química , Alginatos/química , Calcio , Agua , Ácidos Hexurónicos/química , Ácido Glucurónico/química
19.
Behav Res Methods ; 56(4): 3242-3258, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38129734

RESUMEN

It is common for some participants in self-report surveys to be careless, inattentive, or lacking in effort. Data quality can be severely compromised by responses that are not based on item content (non-content-based [nCB] responses), leading to strong biases in the results of data analysis and misinterpretation of individual scores. In this study, we propose a specification of factor mixture analysis (FMA) to detect nCB responses. We investigated the usefulness and effectiveness of the FMA model in detecting nCB responses using both simulated data (Study 1) and real data (Study 2). In the first study, FMA showed reasonably robust sensitivity (.60 to .86) and excellent specificity (.96 to .99) on mixed-worded scales, suggesting that FMA had superior properties as a screening tool under different sample conditions. However, FMA performance was poor on scales composed of only positive items because of the difficulty in distinguishing acquiescent patterns from valid responses representing high levels of the trait. In Study 2 (real data), FMA detected a minority of cases (6.5%) with highly anomalous response patterns. Removing these cases resulted in a large increase in the fit of the unidimensional model and a substantial reduction in spurious multidimensionality.


Asunto(s)
Autoinforme , Humanos , Análisis Factorial , Encuestas y Cuestionarios , Interpretación Estadística de Datos , Modelos Estadísticos
20.
J Infect Dis ; 228(3): 245-250, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-36967714

RESUMEN

Convalescent plasma (CP) treatment of coronavirus disease 2019 (COVID-19) has shown significant therapeutic effect when administered early (eg, Argentinian trial showing reduced hospitalization) but has in general been ineffective (eg, REMAP-CAP trial without improvement during hospitalization). To investigate whether the differences in CP used could explain the different outcomes, we compared neutralizing antibodies, anti-spike IgG, and avidity of CP used in the REMAP-CAP and Argentinian trials and in convalescent vaccinees. We found no difference between the trial plasmas, emphasizing initial patient serostatus as treatment efficacy predictor. By contrast, vaccinee CP showed significantly higher titers and avidity, being preferable for future CP treatment. Clinical Trials Registration. NCT02735707 and NCT04479163.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Donantes de Sangre , COVID-19/terapia , Sueroterapia para COVID-19 , Inmunización Pasiva
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