Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Immunity ; 56(11): 2621-2634.e6, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37967533

RESUMEN

There is growing appreciation for neuraminidase (NA) as an influenza vaccine target; however, its antigenicity remains poorly characterized. In this study, we isolated three broadly reactive N2 antibodies from the plasmablasts of a single vaccinee, including one that cross-reacts with NAs from seasonal H3N2 strains spanning five decades. Although these three antibodies have diverse germline usages, they recognize similar epitopes that are distant from the NA active site and instead involve the highly conserved underside of NA head domain. We also showed that all three antibodies confer prophylactic and therapeutic protection in vivo, due to both Fc effector functions and NA inhibition through steric hindrance. Additionally, the contribution of Fc effector functions to protection in vivo inversely correlates with viral growth inhibition activity in vitro. Overall, our findings advance the understanding of NA antibody response and provide important insights into the development of a broadly protective influenza vaccine.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Infecciones por Orthomyxoviridae , Humanos , Gripe Humana/prevención & control , Neuraminidasa , Infecciones por Orthomyxoviridae/prevención & control , Subtipo H3N2 del Virus de la Influenza A , Epítopos , Anticuerpos Antivirales , Anticuerpos Monoclonales , Vacunación , Glicoproteínas Hemaglutininas del Virus de la Influenza
2.
PLoS Pathog ; 18(9): e1010875, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36155668

RESUMEN

Egg-adaptive mutations in influenza hemagglutinin (HA) often emerge during the production of egg-based seasonal influenza vaccines, which contribute to the largest share in the global influenza vaccine market. While some egg-adaptive mutations have minimal impact on the HA antigenicity (e.g. G186V), others can alter it (e.g. L194P). Here, we show that the preference of egg-adaptive mutation in human H3N2 HA is strain-dependent. In particular, Thr160 and Asn190, which are found in many recent H3N2 strains, restrict the emergence of L194P but not G186V. Our results further suggest that natural amino acid variants at other HA residues also play a role in determining the preference of egg-adaptive mutation. Consistently, recent human H3N2 strains from different clades acquire different mutations during egg passaging. Overall, these results demonstrate that natural mutations in human H3N2 HA can influence the preference of egg-adaptation mutation, which has important implications in seed strain selection for egg-based influenza vaccine.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Aminoácidos/genética , Animales , Pollos , Huevos , Evolución Molecular , Glicoproteínas Hemaglutininas del Virus de la Influenza , Hemaglutininas , Humanos , Subtipo H3N2 del Virus de la Influenza A/genética , Vacunas contra la Influenza/genética , Mutación
3.
Dis Colon Rectum ; 67(6): 834-840, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38426539

RESUMEN

BACKGROUND: Postoperative bowel dysfunction, also known as low anterior resection syndrome, is common in rectal cancer survivors and significantly impacts quality of life. Although long-term longitudinal follow-up is lacking, improvement of the syndrome is commonly believed to happen only within the first 2 years. OBJECTIVE: This study aimed to depict the longitudinal evolvement of low anterior resection syndrome beyond 3 years and explore factors associated with changes. DESIGN: Longitudinal long-term follow-ups were performed for the single center with the largest cohort within the multicenter FOWARC randomized controlled trial. SETTING: A quaternary referral center. PATIENTS: Individuals diagnosed with rectal cancer who received long-course neoadjuvant chemotherapy or chemoradiotherapy, followed by sphincter-preserving radical proctectomy. MAIN OUTCOME MEASUREMENTS: Change of low anterior resection syndrome score and stoma status. RESULTS: Of the 220 patients responding to the first follow-up at a median of 39 months, 178 (80.9%) responded to the second follow-up after a median of 83 months. During this interval, the mean low anterior resection syndrome score improved from 29.5 (95% CI, 28.3-30.7) to 18.6 (95% CI, 16.6-20.6). Fifty-six (31.5%) patients reported improvement from major to no/minor severity, and 6 (3.4%) patients had new stomas because of severe bowel dysfunction. Neoadjuvant radiotherapy ( p = 0.016) was independently and negatively associated with improvement of the score. LIMITATIONS: Loss of follow-up during the long-term follow-ups. CONCLUSIONS: Most rectal cancer survivors with low anterior resection syndrome continued to improve beyond 3 years after proctectomy. Neoadjuvant radiotherapy was negatively associated with long-term improvement of low anterior resection syndrome. See Video Abstract . CAMBIO A LARGO PLAZO DEL SNDROME DE RESECCIN ANTERIOR BAJA EN SUPERVIVIENTES DE CNCER DE RECTO SEGUIMIENTO LONGITUDINAL DE UN ENSAYO CONTROLADO ALEATORIO: ANTECEDENTES:La disfunción intestinal posoperatoria, también conocida como síndrome de resección anterior baja, es común en los sobrevivientes de cáncer de recto y afecta significativamente la calidad de vida. Aunque falta un seguimiento longitudinal a largo plazo, comúnmente se cree que la mejoría del síndrome ocurre sólo dentro de los primeros dos años.OBJETIVO:Este estudio tiene como objetivo representar la evolución longitudinal del síndrome de resección anterior baja más allá de los 3 años y explora los factores asociados con el cambio.DISEÑO:Se realizaron seguimientos longitudinales a largo plazo para el único centro con la cohorte más grande dentro del ensayo controlado aleatorio multicéntrico FOWARC.AJUSTE:Un centro de referencia cuaternario.PACIENTES:Individuos diagnosticados con cáncer de recto que recibieron quimioterapia neoadyuvante de larga duración o quimiorradioterapia, seguida de proctectomía radical con preservación del esfínter.PRINCIPALES MEDICIONES DE RESULTADO:Cambio en la puntuación del síndrome de resección anterior baja y el estado del estoma.RESULTADOS:De los 220 pacientes que respondieron al primer seguimiento con una mediana de 39 meses, 178 (80,9%) respondieron al segundo seguimiento después de una mediana de 83 meses. Durante el intervalo, la puntuación media del síndrome de resección anterior baja mejoró de 29,5 (intervalo de confianza [IC] del 95%: 28,3-30,7) a 18,6 (IC del 95%: 16,6-20,6). 56 (31,5%) pacientes informaron una mejoría de mayor a ninguna gravedad, y 6 (3,4%) pacientes tuvieron un nuevo estoma debido a una disfunción intestinal grave. La radiación neoadyuvante (p = 0,016) se asoció de forma independiente y negativa con la mejora de la puntuación.LIMITACIONES:Pérdida de seguimiento durante los seguimientos a largo plazo.CONCLUSIÓN:La mayoría de los sobrevivientes de cáncer de recto con síndrome de resección anterior baja continuaron mejorando más allá de los 3 años después de la proctectomía. La radiación neoadyuvante se asoció negativamente con la mejora a largo plazo del síndrome de resección anterior baja. (Traducción-Dr Yolanda Colorado ).


Asunto(s)
Supervivientes de Cáncer , Terapia Neoadyuvante , Complicaciones Posoperatorias , Proctectomía , Neoplasias del Recto , Humanos , Neoplasias del Recto/cirugía , Neoplasias del Recto/terapia , Masculino , Femenino , Proctectomía/métodos , Proctectomía/efectos adversos , Persona de Mediana Edad , Anciano , Síndrome , Supervivientes de Cáncer/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios de Seguimiento , Estudios Longitudinales , Terapia Neoadyuvante/métodos , Calidad de Vida , Incontinencia Fecal/etiología , Incontinencia Fecal/epidemiología , Adulto , Síndrome de Resección Anterior Baja
4.
Proc Natl Acad Sci U S A ; 118(25)2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-34099577

RESUMEN

Coronaviruses are pathogens of pandemic potential. Middle East respiratory syndrome coronavirus (MERS-CoV) causes a zoonotic respiratory disease of global public health concern, and dromedary camels are the only proven source of zoonotic infection. More than 70% of MERS-CoV-infected dromedaries are found in East, North, and West Africa, but zoonotic MERS disease is only reported from the Arabian Peninsula. We compared viral replication competence of clade A and B viruses from the Arabian Peninsula with genetically diverse clade C viruses found in East (Egypt, Kenya, and Ethiopia), North (Morocco), and West (Nigeria and Burkina Faso) Africa. Viruses from Africa had lower replication competence in ex vivo cultures of the human lung and in lungs of experimentally infected human-DPP4 (hDPP4) knockin mice. We used lentivirus pseudotypes expressing MERS-CoV spike from Saudi Arabian clade A prototype strain (EMC) or African clade C1.1 viruses and demonstrated that clade C1.1 spike was associated with reduced virus entry into the respiratory epithelial cell line Calu-3. Isogenic EMC viruses with spike protein from EMC or clade C1.1 generated by reverse genetics showed that the clade C1.1 spike was associated with reduced virus replication competence in Calu-3 cells in vitro, in ex vivo human bronchus, and in lungs of hDPP4 knockin mice in vivo. These findings may explain why zoonotic MERS disease has not been reported from Africa so far, despite exposure to and infection with MERS-CoV.


Asunto(s)
Coronavirus del Síndrome Respiratorio de Oriente Medio/genética , Zoonosis/virología , África , Animales , Arabia , Línea Celular , Dipeptidil Peptidasa 4/metabolismo , Técnicas de Sustitución del Gen , Humanos , Cinética , Coronavirus del Síndrome Respiratorio de Oriente Medio/fisiología , Fenotipo , Filogenia , Glicoproteína de la Espiga del Coronavirus/metabolismo , Replicación Viral/fisiología
5.
Eur J Immunol ; 51(9): 2296-2305, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34089541

RESUMEN

The increasing numbers of infected cases of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses serious threats to public health and the global economy. Most SARS-CoV-2 neutralizing antibodies target the receptor binding domain (RBD) and some the N-terminal domain (NTD) of the spike protein, which is the major antigen of SARS-CoV-2. While the antibody response to RBD has been extensively characterized, the antigenicity and immunogenicity of the NTD protein are less well studied. Using 227 plasma samples from COVID-19 patients, we showed that SARS-CoV-2 NTD-specific antibodies could be induced during infection. As compared to the results of SARS-CoV-2 RBD, the serological response of SARS-CoV-2 NTD is less cross-reactive with SARS-CoV, a pandemic strain that was identified in 2003. Furthermore, neutralizing antibodies are rarely elicited in a mice model when NTD is used as an immunogen. We subsequently demonstrate that NTD has an altered antigenicity when expressed alone. Overall, our results suggest that while NTD offers a supplementary strategy for serology testing, it may not be suitable as an immunogen for vaccine development.


Asunto(s)
COVID-19/inmunología , Dominios Proteicos/inmunología , SARS-CoV-2/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Línea Celular , Chlorocebus aethiops , Reacciones Cruzadas/inmunología , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Pandemias/prevención & control , Unión Proteica/inmunología , Células Sf9 , Células Vero
6.
J Infect Dis ; 223(8): 1390-1399, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-32840612

RESUMEN

BACKGROUND: Epidemiologic reports suggest that the most severe or fatal adenoviral disease in children might be associated with human adenovirus (HAdV) type 7. However, the pathogenesis of HAdV-7-induced severe disease remains poorly understood. METHODS: HAdV-3 and HAdV-7 replication kinetics and the host response to infection were compared using ex vivo human lung tissue cultures. Furthermore, cytokine and chemokine levels and the presence of adenovirus DNA in the serum of hospitalized children infected with HAdV-7 (n = 65) or HAdV-3 (n = 48) were measured (using a multiplex immunoassay and Taqman real-time polymerase chain reaction, respectively). RESULTS: Among 471 HAdV-positive specimens, HAdV-3 or HAdV-7 was the most prevalent genotype during 2014-2016 or 2018, respectively. The incidence of severe pneumonia was higher in HAdV-7-infected than in HAdV-3-infected individuals (30.1% vs 4.5%, respectively). HAdV-7 replicated more efficiently than HAdV-3 ex vivo. Interferon-induced protein 10, interleukin 6, and monocyte chemoattractant protein 1 levels were significantly higher in HAdV-7-infected than in HAdV-3-infected children. Adenovirus DNA was detected in serum samples from 40% and 4.2% of HAdV-7- and HAdV-3-infected children, respectively. Furthermore, viremia was strongly associated with severe clinical presentations. CONCLUSIONS: The pathogenesis of HAdV-7-induced severe disease was probably associated with high replication competence and hyperinflammatory responses. The detection of adenovirus DNA in blood may be useful in assessing risk for severe disease.


Asunto(s)
Infecciones por Adenovirus Humanos , Adenovirus Humanos , Inmunidad Innata , Infecciones por Adenovirus Humanos/inmunología , Adenovirus Humanos/clasificación , Niño , Humanos , Incidencia , Viremia
7.
Nephrology (Carlton) ; 24(4): 481-488, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29934960

RESUMEN

AIMS: Metformin is a biguanide derivative widely used for the treatment of type 2 diabetes mellitus. Recent evidence demonstrates that this anti-hyperglycaemic drug exerts renal protective effects, yet the mechanisms remain poorly understood. monocyte chemoattractant protein 1 (MCP-1) has been recognized as a key mediator of renal fibrosis in chronic kidney diseases, including diabetic nephropathy. This study aimed to investigate the effects of metformin on transforming growth factor beta 1 (TGF-ß1)-induced MCP-1 expression and the underlying mechanisms in rat renal tubular epithelial cells. METHODS: Rat renal tubular epithelial cell line NRK-52E cells were stimulated with TGF-ß1 and/or metformin. The messenger RNA (mRNA) of MCP-1 and bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) was evaluated by real-time quantitative polymerase chain reaction. MCP-1 protein was measured by enzyme linked immunosorbent assay (ELISA). Total and phosphorylated extracellular signal-regulated kinases 1/2 (ERK1/2) was evaluated by western blot. Down- and upregulation of BAMBI were achieved by RNA interference targeting BAMBI and lentiviral vector-mediated overexpression of the BAMBI gene, respectively. Cell viability was analysed using Cell Counting Kit 8 (CCK-8) reagents. RESULTS: Stimulation with TGF-ß1 resulted in the increased expression of MCP-1 and decreased expression of BAMBI in NRK-52E cells. Metformin inhibited the expression of MCP-1 in NRK-52E cells. Pretreatment with metformin suppressed upregulation of MCP-1 and downregulation of BAMBI, as well as phosphorylation of ERK1/2 induced by TGF-ß1. U0126, a specific inhibitor for mitogen-activated and extracellular signal-regulated kinase kinases 1/2 (MEK-1/2), completely blocked TGF-ß1-induced MCP-1 expression. Knockdown of the BAMBI gene promoted phosphorylation of ERK1/2 and TGF-ß1-induced expression of MCP-1. Overexpression of BAMBI inhibited phosphorylation of ERK1/2 and TGF-ß1-induced upregulation of MCP-1. CONCLUSION: In rat renal tubular epithelial cells, metformin prevents TGF-ß1-induced MCP-1 expression, in which BAMBI-mediated inhibition of MEK/ERK1/2 might be involved.


Asunto(s)
Quimiocina CCL2/metabolismo , Células Epiteliales/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Túbulos Renales/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Metformina/farmacología , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Animales , Línea Celular , Quimiocina CCL2/genética , Células Epiteliales/enzimología , Células Epiteliales/patología , Fibrosis , Túbulos Renales/enzimología , Túbulos Renales/patología , Proteínas de la Membrana/genética , Fosforilación , Ratas , Transducción de Señal/efectos de los fármacos
8.
Adv Mater ; 36(11): e2305400, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38010313

RESUMEN

Wet-adhesive hydrogels have been developed as an attractive strategy for tissue repair. However, achieving simultaneously low swelling and high burst pressure tolerance of wet-adhesive hydrogels is crucial for in vivo application which remains challenges. Herein, a novel super-structured porous hydrogel (denoted as PVA/PAAc-N+ ) is designed via facile moisture-induced phase separation-solvent exchange process for obtaining porous polyvinyl alcohol (PVA) hydrogel as dissipative layer and in situ photocuring technology for entangling quaternary ammonium-functionalized poly(acrylic acid)-based wet-adhesive layer (PAAc-N+ ) with the porous surface of PVA layer. Benefitting from the ionic crosslinking between quaternary ammonium ions and carboxylate ions in PAAc-N+ wet-adhesive layer as well as the high crystallinity induced by abundant hydrogen bonds of PVA layer, the hydrogel has unique ultralow swelling property (0.29) without sacrificing adhesion strength (63.1 kPa). The porous structure of PVA facilitates the mechanical interlock at the interface between PAAc-N+ wet-adhesive layer and tough PVA dissipative layer, leading to the ultrahigh burst pressure tolerance up to 493 mm Hg and effective repair for porcine heart rupture; the PVA layer surface of PVA/PAAc-N+ hydrogel can prevent postoperative adhesion. By integrating ultralow swelling, ultrahigh burst pressure tolerance, and anti-postoperative adhesion properties, PVA/PAAc-N+ hydrogel shows an appealing application prospect for tissue repair.


Asunto(s)
Compuestos de Amonio , Hidrogeles , Animales , Porcinos , Hidrogeles/química , Adherencias Tisulares/prevención & control , Materiales Biocompatibles/química , Iones , Alcohol Polivinílico/química
9.
Adv Sci (Weinh) ; 11(21): e2308590, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38509840

RESUMEN

Pelvic organ prolapse (POP) is one of the most common pelvic floor dysfunction disorders worldwide. The weakening of pelvic connective tissues initiated by excessive collagen degradation is a leading cause of POP. However, the patches currently used in the clinic trigger an unfavorable inflammatory response, which often leads to implantation failure and the inability to simultaneously reverse progressive collagen degradation. Therefore, to overcome the present challenges, a new strategy is applied by introducing puerarin (Pue) into poly(l-lactic acid) (PLLA) using electrospinning technology. PLLA improves the mechanical properties of the patch, while Pue offers intrinsic anti-inflammatory and pro-collagen synthesis effects. The results show that Pue is released from PLLA@Pue in a sustained manner for more than 20 days, with a total release rate exceeding 80%. The PLLA@Pue electrospun patches also show good biocompatibility and low cytotoxicity. The excellent anti-inflammatory and pro-collagen synthesis properties of the PLLA@Pue patch are demonstrated both in vitro in H2O2-stimulated mouse fibroblasts and in vivo in rat abdominal wall muscle defects. Therefore, it is believed that this multifunctional electrospun patch integrating anti-inflammatory and pro-collagen synthesis properties can overcome the limitations of traditional patches and has great prospects for efficient pelvic floor reconstruction.


Asunto(s)
Antiinflamatorios , Colágeno , Isoflavonas , Diafragma Pélvico , Prolapso de Órgano Pélvico , Animales , Isoflavonas/farmacología , Ratas , Antiinflamatorios/farmacología , Ratones , Prolapso de Órgano Pélvico/cirugía , Poliésteres/química , Modelos Animales de Enfermedad , Ratas Sprague-Dawley
10.
Nat Commun ; 15(1): 5175, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890325

RESUMEN

The receptor-binding site of influenza A virus hemagglutinin partially overlaps with major antigenic sites and constantly evolves. In this study, we observe that mutations G186D and D190N in the hemagglutinin receptor-binding site have coevolved in two recent human H3N2 clades. X-ray crystallography results show that these mutations coordinately drive the evolution of the hemagglutinin receptor binding mode. Epistasis between G186D and D190N is further demonstrated by glycan binding and thermostability analyses. Immunization and neutralization experiments using mouse and human samples indicate that the evolution of receptor binding mode is accompanied by a change in antigenicity. Besides, combinatorial mutagenesis reveals that G186D and D190N, along with other natural mutations in recent H3N2 strains, alter the compatibility with a common egg-adaptive mutation in seasonal influenza vaccines. Overall, our findings elucidate the role of epistasis in shaping the recent evolution of human H3N2 hemagglutinin and substantiate the high evolvability of its receptor-binding mode.


Asunto(s)
Epistasis Genética , Evolución Molecular , Glicoproteínas Hemaglutininas del Virus de la Influenza , Subtipo H3N2 del Virus de la Influenza A , Gripe Humana , Humanos , Subtipo H3N2 del Virus de la Influenza A/genética , Subtipo H3N2 del Virus de la Influenza A/metabolismo , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/química , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Animales , Ratones , Sitios de Unión , Gripe Humana/virología , Mutación , Cristalografía por Rayos X , Vacunas contra la Influenza , Unión Proteica , Receptores Virales/metabolismo , Receptores Virales/genética , Receptores Virales/química , Femenino
11.
Nat Commun ; 15(1): 2546, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38514647

RESUMEN

Influenza virus continuously evolves to escape human adaptive immunity and generates seasonal epidemics. Therefore, influenza vaccine strains need to be updated annually for the upcoming flu season to ensure vaccine effectiveness. We develop a computational approach, beth-1, to forecast virus evolution and select representative virus for influenza vaccine. The method involves modelling site-wise mutation fitness. Informed by virus genome and population sero-positivity, we calibrate transition time of mutations and project the fitness landscape to future time, based on which beth-1 selects the optimal vaccine strain. In season-to-season prediction in historical data for the influenza A pH1N1 and H3N2 viruses, beth-1 demonstrates superior genetic matching compared to existing approaches. In prospective validations, the model shows superior or non-inferior genetic matching and neutralization against circulating virus in mice immunization experiments compared to the current vaccine. The method offers a promising and ready-to-use tool to facilitate vaccine strain selection for the influenza virus through capturing heterogeneous evolutionary dynamics over genome space-time and linking molecular variants to population immune response.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Humanos , Animales , Ratones , Vacunas contra la Influenza/genética , Subtipo H3N2 del Virus de la Influenza A/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Mutación , Estaciones del Año
12.
Int J Infect Dis ; 135: 1-4, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37481108

RESUMEN

OBJECTIVES: Since the onset of the COVID-19 pandemic in 2020, there has been a significant decline in seasonal influenza infection cases in Hong Kong. However, this decline has also resulted in reduced opportunities for the development of influenza-specific antibodies in the community. The levels of antibodies required for protection against recently circulating influenza A viruses in the post-COVID-19 era remain unclear. METHODS: This study involved the analysis of paired plasma samples collected from 479 healthy adults in Hong Kong in 2021 and 2022. The neutralizing titers of plasma against influenza A (H1N1) and (H3N2) viruses circulating before and after the COVID-19 outbreak were determined using a microneutralization assay. RESULTS: The H1N1 and H3N2 vaccine strains selected for the 2022/23 season were found to be closely related to the recently circulating viruses. However, in the samples collected in 2022, only 14.61% and 0.42% showed a neutralization titer (MN50) ≥1:20 against H1N1 A/Wisconsin/588/2019 (H1/Wis19) and H3N2 A/Darwin/6/2021 (H3/Dar21), respectively. Notably, participants who reported receiving annual flu vaccinations exhibited a higher seropositive rate for H1/Wis19 compared to those who had never received the flu vaccine (28.06% vs. 5.30%). CONCLUSION: Our results indicate that adults in Hong Kong generally lack neutralizing antibodies against circulating influenza A viruses, particularly H3N2. These findings underscore the importance of promoting flu vaccination in the post-COVID-19 era.


Asunto(s)
COVID-19 , Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Adulto , Humanos , Anticuerpos Neutralizantes , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Estaciones del Año , Subtipo H3N2 del Virus de la Influenza A , Hong Kong/epidemiología , Pandemias , Estudios Retrospectivos , COVID-19/epidemiología , COVID-19/prevención & control , Anticuerpos Antivirales
13.
Int J Infect Dis ; 127: 26-32, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36481488

RESUMEN

OBJECTIVES: Four seasonal coronaviruses, including human coronavirus (HCoV)-229E and HCoV-OC43, HCoV-NL63, and HCoV-HKU1 cause approximately 15-30% of common colds in adults. However, the full landscape of the immune trajectory to these viruses that covers the whole childhood period is still not well understood. METHODS: We evaluated the serological responses against the four seasonal coronaviruses in 1886 children aged under 18 years by using enzyme-linked immunosorbent assay. The optical density values against each HCoV were determined from each sample. Generalized additive models were constructed to determine the relationship between age and seroprevalence throughout the whole childhood period. The specific antibody levels against the four seasonal coronaviruses were also tested from the plasma samples of 485 pairs of postpartum women and their newborn babies. RESULTS: The immunoglobulin (Ig) G levels of the four seasonal coronaviruses in the mother and the newborn babies were highly correlated (229E: r = 0.63; OC43: r = 0.65; NL63: r = 0.69; HKU1: r = 0.63). The seroprevalences in children showed a similar trajectory in that the levels of IgG in the neonates dropped significantly and reached the lowest level after the age of around 1 year (229E: 1.18 years; OC43: 0.97 years; NL63: 1.01 years; HKU1: 1.02 years) and then resurgence in the children who aged older than 1 year. Using the lowest level from the generalized additive models as our cutoff, the seroprevalences for HCoV-229E, HCoV-OC43, HCoV-NL63, and HCoV-HKU1 were 98.11%, 96.23%, 96.23% and 94.34% at the age of 16-18 years. CONCLUSION: Mothers share HCoV-specific IgGs with their newborn babies and the level of maternal IgGs waned at around 1 year after birth. The resurgence of the HCoV-specific IgGs was found thereafter with the increase in age suggesting repeated infection occurred in children.


Asunto(s)
Infecciones por Coronavirus , Coronavirus Humano OC43 , Coronavirus , Lactante , Recién Nacido , Adulto , Humanos , Niño , Femenino , Adolescente , Estudios Seroepidemiológicos , Estaciones del Año , China/epidemiología , Madres , Inmunoglobulina G
14.
Adv Mater ; 34(15): e2108992, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34981867

RESUMEN

Implantable meshes used in tension-free repair operations facilitate treatment of internal soft-tissue defects. However, clinical meshes fail to achieve anti-deformation, anti-adhesion, and pro-healing properties simultaneously, leading to undesirable surgery outcomes. Herein, inspired by the peritoneum, a novel biocompatible Janus porous poly(vinyl alcohol) hydrogel (JPVA hydrogel) is developed to achieve efficient repair of internal soft-tissue defects by a facile yet efficient strategy based on top-down solvent exchange. The densely porous and smooth bottom-surface of JPVA hydrogel minimizes adhesion of fibroblasts and does not trigger any visceral adhesion, and its loose extracellular-matrix-like porous and rough top-surface can significantly improve fibroblast adhesion and tissue growth, leading to superior abdominal wall defect treatment to commercially available PP and PCO meshes. With unique anti-swelling property (maximum swelling ratio: 6.4%), JPVA hydrogel has long-lasting anti-deformation performance and maintains high mechanical strength after immersion in phosphate-buffered saline (PBS) for 14 days, enabling tolerance to the maximum abdominal pressure in an internal wet environment. By integrating visceral anti-adhesion and defect pro-healing with anti-deformation, the JPVA hydrogel patch shows great prospects for efficient internal soft-tissue defect repair.


Asunto(s)
Pared Abdominal , Peritoneo , Pared Abdominal/cirugía , Materiales Biocompatibles/farmacología , Humanos , Hidrogeles , Porosidad , Adherencias Tisulares
15.
Sensors (Basel) ; 11(4): 3418-38, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22163804

RESUMEN

For mission-critical applications of wireless sensor networks (WSNs) involving extensive battlefield surveillance, medical healthcare, etc., it is crucial to have low-power, new protocols, methodologies and structures for transferring data and information in a network with full sensing coverage capability for an extended working period. The upmost mission is to ensure that the network is fully functional providing reliable transmission of the sensed data without the risk of data loss. WSNs have been applied to various types of mission-critical applications. Coverage preservation is one of the most essential functions to guarantee quality of service (QoS) in WSNs. However, a tradeoff exists between sensing coverage and network lifetime due to the limited energy supplies of sensor nodes. In this study, we propose a routing protocol to accommodate both energy-balance and coverage-preservation for sensor nodes in WSNs. The energy consumption for radio transmissions and the residual energy over the network are taken into account when the proposed protocol determines an energy-efficient route for a packet. The simulation results demonstrate that the proposed protocol is able to increase the duration of the on-duty network and provide up to 98.3% and 85.7% of extra service time with 100% sensing coverage ratio comparing with LEACH and the LEACH-Coverage-U protocols, respectively.


Asunto(s)
Redes de Comunicación de Computadores , Telemetría/métodos , Tecnología Inalámbrica , Algoritmos , Simulación por Computador , Suministros de Energía Eléctrica , Servicios Médicos de Urgencia , Humanos , Ondas de Radio
16.
Transl Cancer Res ; 10(2): 581-588, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35116392

RESUMEN

BACKGROUND: Ileostomy was widely used during colorectal cancer (CRC) surgery and peristomal dermatitis was one of the most common stoma-relative complications. Stoma education class may reduce the rate of peristomal dermatitis. METHODS: We enrolled patients who were diagnosed with rectal cancer and underwent surgery with ileostomy between January 2018 to December 2018 at a single tertiary hospital. The general demographic information of patients along with the participation in stoma education class and the occurrence of peristomal dermatitis were analyzed. RESULTS: A total of 491 patients were included in the study, and 162 patients (32.99%) participated in the stoma education class. Eighty-five patients (17.31%) suffered peristomal dermatitis within one month after ileostomy. The rate of peristomal dermatitis in the stoma education group was significantly lower than that in the control group (11.11% vs. 20.36%, P=0.011). Regardless of the education level, the risk of peristomal dermatitis in the education group was reduced (P<0.05). Lower peristomal dermatitis rates were found in patients who were younger than 60 years (P=0.012), whose stoma were taken care of by other people (P=0.014), or without diabetes (P=0.026). Univariate and Multivariate analysis showed that stoma education was the only factor associated with the decrease in rates of peristomal dermatitis (OR =0.458, P=0.008), while diabetes was an independent risk factor (OR =3.732, P<0.001). CONCLUSIONS: Postoperative stoma education class significantly decreased the rate of peristomal dermatitis in the early postoperative period in CRC patients with ileostomy, especially for those who were younger than 60 years, received stoma care from others or without diabetes.

17.
Cancer Manag Res ; 13: 3193-3200, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33889022

RESUMEN

PURPOSE: Anastomotic leakage after rectal cancer surgery in elderly patients is a critical challenge. Many risk factors have been found and many interventions tried, but anastomotic leakage in elderly patients remains difficult to deal with. This study aimed to create a nomogram for predicting anastomotic leakage after rectal surgery in elderly rectal cancer patients with dysfunctional stomata. METHODS: We collected data from 326 consecutive elderly patients with dysfunctional stomata after rectal cancer surgery at the Sixth Affiliated Hospital, Sun Yat-Sen University from January 2014 to December 2019. Risk factors of anastomotic leakage were identified with multivariate logistic regression and used to create a nomogram. Predictive performance was evaluated by the area under the receiver-operating characteristic (ROC) curve. RESULTS: American Society of Anesthesiologists score ≥3, male sex, and neoadjuvant radiotherapy were identified as significantly associated factors that could be combined for accurate prediction of anastomotic leakage on multivariate logistic regression and development of a nomogram.The area under the ROC curve for this model was 0.645. The C-index value for this model was 0.645, indicating moderate predictive ability of the risk of anastomotic leakage. CONCLUSION: The nomogram showed good ability to predict anastomotic leakage in elderly patients with rectal cancer after surgery, and might be helpful in providing a reference point for selection of surgical procedures and perioperative treatment.

18.
J Mol Neurosci ; 71(2): 302-324, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32757108

RESUMEN

By measuring the cerebral infarction rate and neurological behavioral score of rats in a sham operation group, an MCAO model control group and an Erigeron breviscapus injection treatment group, we explored the therapeutic effects of Erigeron breviscapus injection on brain tissue and neuroethological injury in rats. Plasma samples were collected at 18 time points after intravenous injection of Erigeron breviscapus. The levels of scutellarin, 4-caffeoylquinic acid, 5-caffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, chlorogenic acid and isochlorogenic acid B in rat plasma at the various time points were determined by an HPLC method, and drug concentration versus time plots were constructed to estimate the pharmacokinetic parameters. Finally, a PK-PD combined model was used to analyze the relationship between the blood concentration, time and therapeutic effects of the seven active components. The results of the pharmacodynamics studies showed that the cerebral infarction rate of rats in the Erigeron breviscapus injection group decreased significantly at 5 min, 10 min, 20 min, 6 h, 8 h, 18 h, 24 h, 32 h, 40 h and 48 h after cerebral ischemia. Abnormal neurological behavior scores were significantly reduced after 4 h of cerebral ischemia. The pharmacokinetics results showed that the seven chemical constituents in Erigeron breviscapus injection reached their highest detection value after 5 min of cerebral ischemia. The lowest detection values of scutellarin and isochlorogenic acid B appeared after 6 h of cerebral ischemia but could not be detected after 8 h. The lowest detection values of 5-caffeoylquinic acid and 4,5-dicaffeoylquinic acid were found in the third hour of cerebral ischemia but not after 4 h. The lowest detection values of 4-caffeoylquinic acid, 3,5-dicaffeoylquinic acid and chlorogenic acid were found during the second hour of cerebral ischemia but not at the third hour. However, at 18 h, 24 h, 32 h and 40 h of cerebral ischemia, the cerebral infarction rates of rats in the Erigeron breviscapus injection group were significantly reduced, with decreased values of 6.22%, 11.71%, 6.92% and 4.96%, respectively, and the effects were stronger than those after 5-20 min of cerebral ischemia. The decreased values reached their highest value after 24 h of cerebral ischemia. Our results show that the effects of Erigeron breviscapus injection on reducing the cerebral infarct rate in MCAO model rats are characterized by a fast onset and long maintenance time. The 5-min blood concentration in cerebral ischemia was the highest test value, and after this time, the cerebral infarction rate of MCAO rats began to decrease. However, the peak value of the effects lagged behind that of the plasma concentration. The maximum effective time for Erigeron breviscapus injection appeared 24 h after cerebral ischemia, which provides a reference for the screening of specific drugs for ischemic stroke, optimal dosing regimens and rational clinical drug use. Graphical Abstract.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Erigeron/química , Infarto de la Arteria Cerebral Media/complicaciones , Fitoterapia , Daño por Reperfusión/tratamiento farmacológico , Animales , Apigenina/sangre , Apigenina/química , Cromatografía Líquida de Alta Presión , Ácidos Ciclohexanocarboxílicos/sangre , Ácidos Ciclohexanocarboxílicos/química , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Medicamentos Herbarios Chinos/farmacocinética , Medicamentos Herbarios Chinos/farmacología , Glucuronatos/sangre , Glucuronatos/química , Inyecciones Intravenosas , Masculino , Estructura Molecular , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/sangre
19.
Gastroenterol Rep (Oxf) ; 9(4): 357-362, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34567568

RESUMEN

BACKGROUND: Surgical-site infection (SSI) was one of the most common post-operative morbidities of ileostomy reversal. Although several skin-closure procedures had been developed to reduce the rate of SSI, the optimal procedure remains unclear. In this study, we compared the effect of two surgical techniques for wound closure following ileostomy reversal: gunsight suture (GS) and linear suture (LS). METHODS: A total of 233 patients who underwent loop ileostomy at the Sixth Affiliated Hospital of Sun Yat-sen University between January 2015 and December 2017 were enrolled into our study. These patients were divided into two groups: the LS group and the GS group. We compared the clinical characteristics between the two groups and analyzed the data using IBM SPSS to identify risk factors for SSI. RESULTS: Both groups successfully underwent surgery. The rate of SSI was significantly lower in the GS group (n = 2, 0.02%) than in the LS group (n = 16, 12.00%, P = 0.007). The length of hospital stay after the operation in the GS group was significantly shorter than that in the LS group (8.1 ± 3.2 vs 10.8 ± 5.4 days, P < 0.001). Multivariate analysis showed that GS was an independent protective risk factor for SSI (odds ratio = 0.212, P = 0.048). CONCLUSIONS: Compared with the LS technique, the GS technique can significantly decrease the rate of SSI and shorten the length of hospital stay after surgery. The GS technique may be recommended for wound closure following ileostomy reversal.

20.
J Biomed Nanotechnol ; 17(3): 399-406, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33875074

RESUMEN

Pelvic organ prolapse (POP) has become one of the most common serious diseases affecting parous women. Weakening of pelvic ligaments plays an essential role in the pathophysiology of POP. Currently, synthetic materials are widely applied for pelvic reconstructive surgery. However, synthetic nondegradable meshes for POP therapy cannot meet the clinical requirements due to its poor biocompatibility. Herein, we fabricated electrospun core-shell nanofibers of poly(l-lactic acid)-hyaluronic acid (PLLA/HA). After that, we combined them with mouse bone marrow-derived mesenchymal stem cells (mBMSCs) to assess the cellular response and pelvic ligament tissue engineering in vitro. The cellular responses on the composite nanofibers showed that the core-shell structure nanofibers displayed with excellent biocompatibility and enhanced cellular activity without cytotoxicity. Moreover, compared with PLLA nanofibers seeded with mBMSCs, PLLA/HA nanofibers exhibited more cellular function, as revealed by the quantitative real-time polymerase chain reaction (RT-qPCR) for pelvic ligament-related gene markers including Col1a1, Col1a3 and Tnc. These features suggested that this novel core-shell nanofiber is promising in stem cell-based tissue engineering for pelvic reconstruction.


Asunto(s)
Nanofibras , Animales , Técnicas de Cultivo de Célula , Proliferación Celular , Ácido Hialurónico , Ácido Láctico , Ligamentos , Ratones , Poliésteres , Ingeniería de Tejidos , Andamios del Tejido
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA