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1.
N Engl J Med ; 385(13): 1172-1183, 2021 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-34192426

RESUMEN

BACKGROUND: Early clinical data from studies of the NVX-CoV2373 vaccine (Novavax), a recombinant nanoparticle vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that contains the full-length spike glycoprotein of the prototype strain plus Matrix-M adjuvant, showed that the vaccine was safe and associated with a robust immune response in healthy adult participants. Additional data were needed regarding the efficacy, immunogenicity, and safety of this vaccine in a larger population. METHODS: In this phase 3, randomized, observer-blinded, placebo-controlled trial conducted at 33 sites in the United Kingdom, we assigned adults between the ages of 18 and 84 years in a 1:1 ratio to receive two intramuscular 5-µg doses of NVX-CoV2373 or placebo administered 21 days apart. The primary efficacy end point was virologically confirmed mild, moderate, or severe SARS-CoV-2 infection with an onset at least 7 days after the second injection in participants who were serologically negative at baseline. RESULTS: A total of 15,187 participants underwent randomization, and 14,039 were included in the per-protocol efficacy population. Of the participants, 27.9% were 65 years of age or older, and 44.6% had coexisting illnesses. Infections were reported in 10 participants in the vaccine group and in 96 in the placebo group, with a symptom onset of at least 7 days after the second injection, for a vaccine efficacy of 89.7% (95% confidence interval [CI], 80.2 to 94.6). No hospitalizations or deaths were reported among the 10 cases in the vaccine group. Five cases of severe infection were reported, all of which were in the placebo group. A post hoc analysis showed an efficacy of 86.3% (95% CI, 71.3 to 93.5) against the B.1.1.7 (or alpha) variant and 96.4% (95% CI, 73.8 to 99.5) against non-B.1.1.7 variants. Reactogenicity was generally mild and transient. The incidence of serious adverse events was low and similar in the two groups. CONCLUSIONS: A two-dose regimen of the NVX-CoV2373 vaccine administered to adult participants conferred 89.7% protection against SARS-CoV-2 infection and showed high efficacy against the B.1.1.7 variant. (Funded by Novavax; EudraCT number, 2020-004123-16.).


Asunto(s)
Vacunas contra la COVID-19 , COVID-19/prevención & control , Inmunogenicidad Vacunal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/epidemiología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/inmunología , Humanos , Inyecciones Intramusculares/efectos adversos , Persona de Mediana Edad , SARS-CoV-2 , Método Simple Ciego , Vacunas Sintéticas/inmunología , Adulto Joven
2.
Anal Chem ; 96(22): 9016-9025, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38780636

RESUMEN

Despite recent advancements in colorectal cancer (CRC) treatment, the prognosis remains unfavorable primarily due to high recurrence and liver metastasis rates. Fluorescence molecular imaging technologies, combined with specific probes, have gained prominence in facilitating real-time tumor resection guided by fluorescence. Hepatocyte growth factor (HGF) is overexpressed in CRC, but the advancement of HGF fluorescent probes has been impeded by the absence of effective HGF-targeting small-molecular ligands. Herein, we present the targeted capabilities of the novel V-1-GGGK-MPA probe labeled with a near-infrared fluorescent dye, which targets HGF in CRC. The V-1-GGGK peptide exhibits high specificity and selectivity for HGF-positive in vitro tumor cells and in vivo tumors. Biodistribution analysis of V-1-GGGK-MPA revealed tumor-specific accumulation with low background uptake, yielding signal-to-noise ratio (SNR) values of tumor-to-colorectal >6 in multiple subcutaneous CRC models 12 h postinjection. Quantitative analysis confirmed the probe's high uptake in SW480 and HT29 orthotopic and liver metastatic models, with SNR values of tumor-to-colorectal and -liver being 5.6 ± 0.4, 4.6 ± 0.5, and 2.1 ± 0.3, 2.0 ± 0.5, respectively, enabling precise tumor visualization for surgical navigation. Pathological analysis demonstrated the excellent tumor boundaries discrimination capacity of the V-1-GGGK-MPA probe at the molecular level. With its rapid tumor targeting, sustained tumor retention, and precise tumor boundary delineation, V-1-GGGK-MPA merges as a promising HGF imaging agent, enriching the toolbox of intraoperative navigational fluorescent probes for CRC.


Asunto(s)
Neoplasias Colorrectales , Colorantes Fluorescentes , Factor de Crecimiento de Hepatocito , Imagen Óptica , Colorantes Fluorescentes/química , Factor de Crecimiento de Hepatocito/metabolismo , Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/patología , Humanos , Animales , Ratones , Ratones Desnudos , Distribución Tisular , Ratones Endogámicos BALB C , Línea Celular Tumoral
3.
Epidemiol Infect ; 152: e37, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38250791

RESUMEN

To investigate the symptoms of SARS-CoV-2 infection, their dynamics and their discriminatory power for the disease using longitudinally, prospectively collected information reported at the time of their occurrence. We have analysed data from a large phase 3 clinical UK COVID-19 vaccine trial. The alpha variant was the predominant strain. Participants were assessed for SARS-CoV-2 infection via nasal/throat PCR at recruitment, vaccination appointments, and when symptomatic. Statistical techniques were implemented to infer estimates representative of the UK population, accounting for multiple symptomatic episodes associated with one individual. An optimal diagnostic model for SARS-CoV-2 infection was derived. The 4-month prevalence of SARS-CoV-2 was 2.1%; increasing to 19.4% (16.0%-22.7%) in participants reporting loss of appetite and 31.9% (27.1%-36.8%) in those with anosmia/ageusia. The model identified anosmia and/or ageusia, fever, congestion, and cough to be significantly associated with SARS-CoV-2 infection. Symptoms' dynamics were vastly different in the two groups; after a slow start peaking later and lasting longer in PCR+ participants, whilst exhibiting a consistent decline in PCR- participants, with, on average, fewer than 3 days of symptoms reported. Anosmia/ageusia peaked late in confirmed SARS-CoV-2 infection (day 12), indicating a low discrimination power for early disease diagnosis.


Asunto(s)
Ageusia , COVID-19 , Humanos , Anosmia/epidemiología , Anosmia/etiología , COVID-19/diagnóstico , Prueba de COVID-19 , Vacunas contra la COVID-19 , Estudios Longitudinales , SARS-CoV-2 , Ensayos Clínicos Fase III como Asunto
4.
Mikrochim Acta ; 191(2): 101, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38231363

RESUMEN

Hyaluronidase (HAase) is an important endoglycosidase involved in numerous physiological and pathological processes, such as apoptosis, senescence, and cancer progression. Simple, convenient, and sensitive detection of HAase is important for clinical diagnosis. Herein, an easy-to-operate multicolor visual sensing strategy was developed for HAase determination. The proposed sensor was composed of an enzyme-responsive hydrogel and a nanochromogenic system (gold nanobipyramids (AuNBPs)). The enzyme-responsive hydrogel, formed by polyethyleneimine-hyaluronic acid (PEI-HA), was specifically hydrolyzed with HAase, leading to the release of platinum nanoparticles (PtNPs). Subsequently, PtNPs catalyzed the mixed system of 3,3',5,5'-tetramethylbenzidine (TMB) and H2O2 to produce TMB2+ under acidic conditions. Then, TMB2+ effectively etched the AuNBPs and resulted in morphological changes in the AuNBPs, accompanied by a blueshift in the localized surface plasmon resonance peak and vibrant colors. Therefore, HAase can be semiquantitatively determined by directly observing the color change of AuNBPs with the naked eye. On the basis of this, the method has a linear detection range of HAase concentrations between 0.6 and 40 U/mL, with a detection limit of 0.3 U/mL. In addition, our designed multicolor biosensor successfully detected the concentration of HAase in human serum samples. The results showed no obvious difference between this method and enzyme-linked immunosorbent assay, indicating the good accuracy and usability of the suggested method.


Asunto(s)
Bencidinas , Hialuronoglucosaminidasa , Nanopartículas del Metal , Humanos , Hidrogeles , Peróxido de Hidrógeno , Platino (Metal)
5.
Circulation ; 146(25): 1950-1967, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36420731

RESUMEN

BACKGROUND: Cardiac regeneration after injury is limited by the low proliferative capacity of adult mammalian cardiomyocytes (CMs). However, certain animals readily regenerate lost myocardium through a process involving dedifferentiation, which unlocks their proliferative capacities. METHODS: We bred mice with inducible, CM-specific expression of the Yamanaka factors, enabling adult CM reprogramming and dedifferentiation in vivo. RESULTS: Two days after induction, adult CMs presented a dedifferentiated phenotype and increased proliferation in vivo. Microarray analysis revealed that upregulation of ketogenesis was central to this process. Adeno-associated virus-driven HMGCS2 overexpression induced ketogenesis in adult CMs and recapitulated CM dedifferentiation and proliferation observed during partial reprogramming. This same phenomenon was found to occur after myocardial infarction, specifically in the border zone tissue, and HMGCS2 knockout mice showed impaired cardiac function and response to injury. Finally, we showed that exogenous HMGCS2 rescues cardiac function after ischemic injury. CONCLUSIONS: Our data demonstrate the importance of HMGCS2-induced ketogenesis as a means to regulate metabolic response to CM injury, thus allowing cell dedifferentiation and proliferation as a regenerative response.


Asunto(s)
Infarto del Miocardio , Miocitos Cardíacos , Ratones , Animales , Miocitos Cardíacos/metabolismo , Corazón , Miocardio/metabolismo , Ratones Noqueados , Regeneración/genética , Proliferación Celular , Mamíferos
6.
Clin Infect Dis ; 76(3): 398-407, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36210481

RESUMEN

BACKGROUND: The recombinant protein-based vaccine, NVX-CoV2373, demonstrated 89.7% efficacy against coronavirus disease 2019 (COVID-19) in a phase 3, randomized, observer-blinded, placebo-controlled trial in the United Kingdom. The protocol was amended to include a blinded crossover. Data to the end of the placebo-controlled phase are reported. METHODS: Adults aged 18-84 years received 2 doses of NVX-CoV2373 or placebo (1:1) and were monitored for virologically confirmed mild, moderate, or severe COVID-19 (onset from 7 days after second vaccination). Participants who developed immunoglobulin G (IgG) against nucleocapsid protein but did not show symptomatic COVID-19 were considered asymptomatic. Secondary outcomes included anti-spike (S) IgG responses, wild-type virus neutralization, and T-cell responses. RESULTS: Of 15 185 participants, 13 989 remained in the per-protocol efficacy population (6989 NVX-CoV2373, 7000 placebo). At a maximum of 7.5 months (median, 4.5) postvaccination, there were 24 cases of COVID-19 among NVX-CoV2373 recipients and 134 cases among placebo recipients, a vaccine efficacy of 82.7% (95% confidence interval [CI], 73.3%-88.8%). Vaccine efficacy was 100% (95% CI, 17.9%-100.0%) against severe disease and 76.3% (95% CI, 57.4%-86.8%) against asymptomatic disease. High anti-S and neutralization responses to vaccination were evident, together with S-protein-specific induction of interferon-γ secretion in peripheral blood T cells. Incidence of serious adverse events and adverse events of special interest were similar between groups. CONCLUSIONS: A 2-dose regimen of NVX-CoV2373 conferred a high level of ongoing protection against asymptomatic, symptomatic, and severe COVID-19 through >6 months postvaccination. A gradual decrease of protection suggests that a booster may be indicated. CLINICAL TRIALS REGISTRATION: EudraCT, 2020-004123-16.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Adulto , Humanos , Vacunas contra la COVID-19/efectos adversos , COVID-19/prevención & control , SARS-CoV-2 , Vacunas Sintéticas/efectos adversos , Inmunoglobulina G , Inmunogenicidad Vacunal , Método Doble Ciego , Anticuerpos Antivirales
7.
Anal Chem ; 95(18): 7344-7353, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37104013

RESUMEN

Surgical resection constitutes the first choice of treatment for colorectal cancer (CRC). Despite advancements in intraoperative navigation, there remains a considerable lack of effective targeting probes for the imaging-guided surgical navigation of CRC owing to their high heterogeneity. Hence, developing a suitable fluorescent probe to detect the specific types of CRC populations is crucial. Herein, we labeled ABT-510, a small, CD36-targeting thrombospondin-1-mimetic peptide overexpressed in various cancer types, with fluorescein isothiocyanate or near-infrared dye MPA. We found that fluorescence-conjugated ABT-510 exhibited excellent selectivity and specificity toward cells or tissues with high CD36 expression. The tumor-to-colorectal signal ratios were 11.28 ± 0.61 (95% confidence interval) and 10.74 ± 0.07 (95% confidence interval) in subcutaneous HCT-116 and HT-29 tumor-bearing nude mice, respectively. Moreover, high signal contrast was observed in the orthotopic and liver metastatic CRC xenograft mouse models. Furthermore, MPA-PEG4-r-ABT-510 exhibited an antiangiogenic effect via tube information assay with human umbilical vein endothelial cells. Overall, MPA-PEG4-r-ABT-510 presents rapid and precise tumor delineation characteristics, thereby making it a desirable tool for CRC imaging and surgical navigation.


Asunto(s)
Neoplasias Colorrectales , Células Endoteliales , Humanos , Ratones , Animales , Células Endoteliales/metabolismo , Ratones Desnudos , Péptidos , Neoplasias Colorrectales/diagnóstico por imagen , Neoplasias Colorrectales/tratamiento farmacológico , Imagen Molecular , Línea Celular Tumoral , Imagen Óptica
8.
Anal Chem ; 95(30): 11429-11439, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37465877

RESUMEN

Despite advancements in pancreatic cancer treatment, it remains one of the most lethal malignancies with extremely poor diagnosis and prognosis. Herein, we demonstrated the efficiency of a novel peptide GB-6 labeled with a near-infrared (NIR) fluorescent dye 3H-indolium, 2-[2-[2-[(2-carboxyethyl)thio]-3-[2-[1,3-dihydro-3,3-dimethyl-5-sulfo-1-(3-sulfopropyl)-2H-indol-2-ylidene]ethylidene]-1-cyclohexen-1-yl]ethenyl]-3,3-dimethyl-5-sulfo-1-(3-sulfopropyl)-, inner salt (MPA) and radionuclide technetium-99m (99mTc) as targeting probes using the gastrin-releasing peptide receptor (GRPR) that is overexpressed in pancreatic cancer as the target. A short linear peptide with excellent in vivo stability was identified, and its radiotracer [99mTc]Tc-HYNIC-PEG4-GB-6 and the NIR probe MPA-PEG4-GB-6 exhibited selective and specific uptake by tumors in an SW1990 pancreatic cancer xenograft mouse model. The favorable biodistribution of the tracer [99mTc]Tc-HYNIC-PEG4-GB-6 in vivo afforded tumor-specific accumulation with high tumor-to-muscle and -bone contrasts and renal body clearance at 1 h after injection. The biodistribution analysis revealed that the tumor-to-pancreas and -intestine fluorescence signal ratios were 5.2 ± 0.3 and 6.3 ± 1.5, respectively, in the SW1990 subcutaneous xenograft model. Furthermore, the high signal accumulation in the orthotopic pancreatic and liver metastasis tumor models with tumor-to-pancreas and -liver fluorescence signal ratios of 7.66 ± 0.48 and 3.94 ± 0.47, respectively, enabled clear tumor visualization for intraoperative navigation. The rapid tumor targeting, precise tumor boundary delineation, chemical versatility, and high potency of the novel GB-6 peptide established it as a high-contrast imaging probe for the clinical detection of GRPR, with compelling additional potential in molecular-targeted therapy.


Asunto(s)
Neoplasias Hepáticas , Neoplasias Pancreáticas , Humanos , Ratones , Animales , Receptores de Bombesina , Distribución Tisular , Línea Celular Tumoral , Péptidos/química , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/patología , Tomografía Computarizada de Emisión de Fotón Único/métodos , Modelos Animales de Enfermedad , Imagen Molecular , Neoplasias Pancreáticas
9.
Anal Chem ; 95(49): 17968-17973, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-38032052

RESUMEN

Extracellular vesicles (EVs) are used by living cells for the purpose of biological information trafficking from parental-to-recipient cells and vice versa. This back-and-forth communication is enabled by two distinct kinds of biomolecules that constitute the cargo of an EV: proteins and nucleic acids. The proteomic-cum-genetic information is mediated by the physiological state of a cell (healthy or otherwise) as much as modulated by the biogenesis pathway of the EV. Therefore, in mirroring the huge diversities of human communications, the proteins and nucleic acids involved in cell communications possess seemingly near limitless diversities, and it is this characteristic that makes EVs so highly heterogeneous. Currently, there is no simple and reliable tool for the selective capture of heterogeneous EVs and the delivery of their undamaged cargo for research in extracellular protein mapping and spatial proteomics studies. Our work is a preliminary attempt to address this issue. We demonstrated our approach by using antibody functionalized liposomes to capture EVs from tumor and healthy cell-lines. To characterize their performance, we presented fluorescence and nanoparticle tracking analysis (NTA) results, TEM images, and Western blotting analysis for EV proteins. We also extracted dermal interstitial fluid (ISF) from healthy individuals and used our functionalized synthetic vesicle (FSV) method to capture EVs from their proteins. We constructed three proteomic sets [EV vs ISF, (FSV+EV) vs ISF, and (FSV+EV) vs EV] from the EV proteins and the free proteins harvested from ISF and compared their differentially expressed proteins (DEPs). The performance of our proposed method is assessed via an analysis of 1095 proteins, together with volcano plots, heatmap, GO annotation, and enriched KEGG pathways and organelle localization results of 213 DEPs.


Asunto(s)
Vesículas Extracelulares , Ácidos Nucleicos , Humanos , Liposomas/metabolismo , Líquido Extracelular , Proteómica/métodos , Vesículas Extracelulares/metabolismo , Ácidos Nucleicos/metabolismo
10.
Small ; 19(24): e2207889, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36899491

RESUMEN

Printed flexible electronics have emerged as versatile functional components of wearable intelligent devices that bridge the digital information networks with biointerfaces. Recent endeavors in plant wearable sensors provide real-time and in situ insights to study phenotyping traits of crops, whereas monitoring of ethylene, the fundamental phytohormone, remains challenging due to the lack of flexible and scalable manufacturing of plant wearable ethylene sensors. Here the all-MXene-printed flexible radio frequency (RF) resonators are presented as plant wearable sensors for wireless ethylene detection. The facile formation of additive-free MXene ink enables rapid, scalable manufacturing of printed electronics, demonstrating decent printing resolution (2.5% variation), ≈30000 S m-1 conductivity and mechanical robustness. Incorporation of MXene-reduced palladium nanoparticles (MXene@PdNPs) facilitates 1.16% ethylene response at 1 ppm with 0.084 ppm limit of detection. The wireless sensor tags are attached on plant organ surfaces for in situ and continuously profiling of plant ethylene emission to inform the key transition of plant biochemistry, potentially extending the application of printed MXene electronics to enable real-time plant hormone monitoring for precision agriculture and food industrial management.


Asunto(s)
Nanopartículas del Metal , Dispositivos Electrónicos Vestibles , Paladio , Productos Agrícolas , Etilenos
11.
J Phys Chem A ; 127(13): 3000-3019, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36897578

RESUMEN

We used aerosol mass spectrometry coupled with tunable synchrotron photoionization to measure radical and closed-shell species associated with particle formation in premixed flames and during pyrolysis of butane, ethylene, and methane. We analyzed photoionization (PI) spectra for the C7H7 radical to identify the isomers present during particle formation. For the combustion and pyrolysis of all three fuels, the PI spectra can be fit reasonably well with contributions from four radical isomers: benzyl, tropyl, vinylcyclopentadienyl, and o-tolyl. Although there are significant experimental uncertainties in the isomeric speciation of C7H7, the results clearly demonstrate that the isomeric composition of C7H7 strongly depends on the combustion or pyrolysis conditions and the fuel or precursors. Fits to the PI spectra using reference curves for these isomers suggest that all of these isomers may contribute to m/z 91 in butane and methane flames, but only benzyl and vinylcyclopentadienyl contribute to the C7H7 isomer signal in the ethylene flame. Only tropyl and benzyl appear to play a role during pyrolytic particle formation from ethylene, and only tropyl, vinylcyclopentadienyl, and o-tolyl appear to participate during particle formation from butane pyrolysis. There also seems to be a contribution from an isomer with an ionization energy below 7.5 eV for the flames but not for the pyrolysis conditions. Kinetic models with updated and new reactions and rate coefficients for the C7H7 reaction network predict benzyl, tropyl, vinylcyclopentadienyl, and o-tolyl to be the primary C7H7 isomers and predict negligible contributions from other C7H7 isomers. These updated models provide better agreement with the measurements than the original versions of the models but, nonetheless, underpredict the relative concentrations of tropyl, vinylcyclopentadienyl, and o-tolyl in both flames and pyrolysis and overpredict benzyl in pyrolysis. Our results suggest that there are additional important formation pathways for the vinylcyclopentadienyl, tropyl, and o-tolyl radicals and/or loss pathways for the benzyl radical that are currently unaccounted for in the present models.

12.
J Dairy Sci ; 106(10): 6880-6893, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37210373

RESUMEN

This study investigated the effect of feeding seaweed (Ascophyllum nodosum) to dairy cows on milk mineral concentrations, feed-to-milk mineral transfer efficiencies, and hematological parameters. Lactating Holstein cows (n = 46) were allocated to 1 of 2 diets (n = 23 each): (1) control (CON; without seaweed) and (2) seaweed (SWD; replacing 330 g/d of dried corn meal in CON with 330 g/d dried A. nodosum). All cows were fed the CON diet for 4 wk before the experiment (adaptation period), and animals were then fed the experimental diets for 9 wk. Samples included sequential 3-wk composite feed samples, a composite milk sample on the last day of each week, and a blood sample at the end of the study. Data were statistically analyzed using a linear mixed effects model with diet, week, and their interaction as fixed factors; cow (nested within diet) as a random factor; and data collected on the last day of the adaptation period as covariates. Feeding SWD increased milk concentrations of Mg (+6.6 mg/kg), P (+56 mg/kg), and I (+1,720 µg/kg). It also reduced transfer efficiency of Ca, Mg, P, K, Mn, and Zn, and increased transfer efficiency of Mo. Feeding SWD marginally reduced milk protein concentrations, whereas there was no effect of SWD feeding on cows' hematological parameters. Feeding A. nodosum increased milk I concentrations, which can be beneficial when feed I concentration is limited or in demographics or populations with increased risk of I deficiency (e.g., female adolescents, pregnant women, nursing mothers). However, care should also be taken when feeding SWD to dairy cows because, in the present study, milk I concentrations were particularly high and could result in I intakes that pose a health risk for children consuming milk.


Asunto(s)
Ascophyllum , Algas Marinas , Niño , Bovinos , Femenino , Embarazo , Animales , Humanos , Adolescente , Lactancia , Alimentación Animal/análisis , Dieta/veterinaria , Minerales/farmacología , Verduras , Suplementos Dietéticos
13.
J Phys Chem A ; 126(19): 3015-3026, 2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35522242

RESUMEN

We have developed a strategy for distinguishing between small-angle X-ray scattering (SAXS) from gas-phase species and newly formed nanoparticles in mixed gas- and particle-phase reacting flows. This methodology explicitly accounts for temperature-dependent scattering from gases. We measured SAXS in situ in a sooting linear laminar partially premixed co-flow ethylene/air diffusion flame. The scattering signal demonstrates a downward curvature as a function of the momentum transfer (q) at q values of 0.2-0.57 Å-1. The q-dependent curvature is consistent with the Debye equation and the independent-atom model for gas-phase scattering. This behavior can also be modeled using the Guinier approximation and could be characterized as a Guinier knee for gas-phase scattering. The Guinier functional form can be fit to the scattering signal in this q range without a priori knowledge of the gas-phase composition, enabling estimation of the gas-phase contribution to the scattering signal while accounting for changes in the gas-phase composition and temperature. We coupled the SAXS measurements with in situ temperature measurements using coherent anti-Stokes Raman spectroscopy. This approach to characterizing the gas-phase SAXS signal provides a physical basis for distinguishing among the contributions to the scattering signal from the instrument function, flame gases, and nanoparticles. The results are particularly important for the analysis of the SAXS signal in the q range associated with particles in the size range of 1-6 nm.

14.
Lett Appl Microbiol ; 74(2): 247-257, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34826147

RESUMEN

Although the microbiology laboratory paradigm has increasingly changed from manual to automated procedures, and from functional to molecular methods, traditional culture methods remain vital. Using inexpensive desktop fused filament fabrication 3D printing, we designed, produced and tested rapid prototypes of customised labware for microbial culture namely frames to make dip slides, inoculation loops, multi-pin replicators, and multi-well culture plates for solid medium. These customised components were used to plate out samples onto solid media in various formats, and we illustrate how they can be suitable for many microbiological methods such as minimum inhibitory concentration tests, or for directly detecting pathogens from mastitis samples, illustrating the flexibility of rapid-prototyped culture consumable parts for streamlining microbiological methods. We describe the methodology needed for microbiologists to develop their own novel and unique tools, or to fabricate and customise existing consumables. A workflow is presented for designing and 3D printing labware and quickly producing easy-to-sterilise and re-useable plastic parts of great utility in the microbiology laboratory.


Asunto(s)
Laboratorios , Impresión Tridimensional , Medios de Cultivo , Plásticos , Flujo de Trabajo
15.
Small ; 17(26): e2100911, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34038614

RESUMEN

Compressible energy devices have received increasing attention with the rapid development of flexible electronics and wearable devices due to their size adaptability and functional stability. However, it is hard to simultaneously achieve satisfactory energy density and mechanical stability for electrodes. Here an open-porous dual network sponge (DNS) with two networks of highly conductive carbon nanotubes and Li+ -intercalating TiO2 -B nanowires is synthesized and employed as compressible lithium ion battery electrodes. All 1D components inside the DNS mutually penetrate with each other to form two physically distinct but functionally coupling networks, endowing DNS excellent compressibility and stability. A prototype compressible lithium-ion battery (C-LIB) is also demonstrated, in which the DNS exhibits a specific capacity of >238 mAh g-1 under static 50% strain, and further in situ measurements show that under 1000 times of cyclic strains, DNS can charge and discharge normally maintaining a high capacity of 240 mAh g-1 and exhibits robustness to fast strain rates up to 500% min-1 . The dual network structure can be extended to design high-performance compliant electrodes that are promising to serve in future compressible and deformable electronics and energy systems.


Asunto(s)
Litio , Nanotubos de Carbono , Suministros de Energía Eléctrica , Electrodos , Iones
16.
J Appl Microbiol ; 130(4): 1337-1356, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32955795

RESUMEN

AIMS: The aim was to understand the time-dependent antibiotic-induced perturbation pattern of gut microbiota and its effect on the innate immune and metabolic profile of the host. METHODS AND RESULTS: Vancomycin was administered at 50 mg kg-1 of body weight twice daily for six consecutive days to perturb the gut microbiota of C57BL/6 (Th1-biased) and BALB/c (Th2-biased) mice. Following treatment with vancomycin, we observed a reduction in the abundance of phyla Firmicutes and Bacteroides and an increase in Proteobacteria in the gut for both strains of mice following treatment with vancomycin till day 4. Abundance of Akkermansia muciniphila of Verrucomicrobia phylum also increased, from day 5 onwards following vancomycin treatment. The time-dependent variation of gut microbiota was associated with increased (i) expression of toll-like receptors and inflammatory genes such as TNF-α, IL-6, and IL-17, (ii) gut barrier permeability and (iii) blood glucose level of the host. The results also showed that (i) transplantation of cecal microbiota from vancomycin-treated day 6 mice to day 3 vancomycin-treated mice helped in restoring blood glucose level in C57BL/6 mice and (ii) short-chain fatty acids like acetate, butyrate and propionate changed with the alteration of gut microbiota to induce differential regulation of host immune response. CONCLUSIONS: The current results revealed that an increase in A. muciniphila led to decreased inflammation and increased rate of glucose tolerance in the host. The treatment, with vancomycin till day 4, increased expression of inflammatory genes. The continuation of vancomycin for two more days reversed the effects. The effects were significantly more in C57BL/6 than BALB/c mice. SIGNIFICANCE AND IMPACT OF THE STUDY: The current study established that the treatment with vancomycin till day 4 increased pathogenic bacteria but day 5 onwards provided significant health-related benefits to the host by increasing A. muciniphila more in C57BL/6 than BALB/c mice.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Vancomicina/farmacología , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Ácidos Grasos Volátiles/metabolismo , Inmunidad Innata/efectos de los fármacos , Metaboloma/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células Th2/efectos de los fármacos , Células Th2/inmunología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología
17.
Circulation ; 139(5): 647-659, 2019 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-30586712

RESUMEN

BACKGROUND: The impact of gut microbiota on the regulation of host physiology has recently garnered considerable attention, particularly in key areas such as the immune system and metabolism. These areas are also crucial for the pathophysiology of and repair after myocardial infarction (MI). However, the role of the gut microbiota in the context of MI remains to be fully elucidated. METHODS: To investigate the effects of gut microbiota on cardiac repair after MI, C57BL/6J mice were treated with antibiotics 7 days before MI to deplete mouse gut microbiota. Flow cytometry was applied to examine the changes in immune cell composition in the heart. 16S rDNA sequencing was conducted as a readout for changes in gut microbial composition. Short-chain fatty acid (SCFA) species altered after antibiotic treatment were identified by high-performance liquid chromatography. Fecal reconstitution, transplantation of monocytes, or dietary SCFA or Lactobacillus probiotic supplementation was conducted to evaluate the cardioprotective effects of microbiota on the mice after MI. RESULTS: Antibiotic-treated mice displayed drastic, dose-dependent mortality after MI. We observed an association between the gut microbiota depletion and significant reductions in the proportion of myeloid cells and SCFAs, more specifically acetate, butyrate, and propionate. Infiltration of CX3CR1+ monocytes to the peri-infarct zone after MI was also reduced, suggesting impairment of repair after MI. Accordingly, the physiological status and survival of mice were significantly improved after fecal reconstitution, transplantation of monocytes, or dietary SCFA supplementation. MI was associated with a reorganization of the gut microbial community such as a reduction in Lactobacillus. Supplementing antibiotic-treated mice with a Lactobacillus probiotic before MI restored myeloid cell proportions, yielded cardioprotective effects, and shifted the balance of SCFAs toward propionate. CONCLUSIONS: Gut microbiota-derived SCFAs play an important role in maintaining host immune composition and repair capacity after MI. This suggests that manipulation of these elements may provide opportunities to modulate pathological outcome after MI and indeed human health and disease as a whole.


Asunto(s)
Antibacterianos/toxicidad , Bacterias/efectos de los fármacos , Microbioma Gastrointestinal/efectos de los fármacos , Monocitos/inmunología , Infarto del Miocardio/microbiología , Miocardio/inmunología , Animales , Bacterias/inmunología , Bacterias/metabolismo , Modelos Animales de Enfermedad , Disbiosis , Ácidos Grasos/administración & dosificación , Ácidos Grasos/metabolismo , Trasplante de Microbiota Fecal , Femenino , Interacciones Huésped-Patógeno , Lactobacillus/inmunología , Lactobacillus/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Monocitos/metabolismo , Monocitos/trasplante , Infarto del Miocardio/inmunología , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Miocardio/metabolismo , Miocardio/patología , Probióticos/administración & dosificación , Células RAW 264.7
18.
Hum Mol Genet ; 27(21): 3675-3687, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30060141

RESUMEN

Fibrillin microfibrils are extracellular matrix assemblies that form the template for elastic fibres, endow blood vessels, skin and other elastic tissues with extensible properties. They also regulate the bioavailability of potent growth factors of the TGF-ß superfamily. A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)10 is an essential factor in fibrillin microfibril function. Mutations in fibrillin-1 or ADAMTS10 cause Weill-Marchesani syndrome (WMS) characterized by short stature, eye defects, hypermuscularity and thickened skin. Despite its importance, there is poor understanding of the role of ADAMTS10 and its function in fibrillin microfibril assembly. We have generated an ADAMTS10 WMS mouse model using Clustered Regularly Spaced Interspaced Short Palindromic Repeats and CRISPR associated protein 9 (CRISPR-Cas9) to introduce a truncation mutation seen in WMS patients. Homozygous WMS mice are smaller and have shorter long bones with perturbation to the zones of the developing growth plate and changes in cell proliferation. Furthermore, there are abnormalities in the ciliary apparatus of the eye with decreased ciliary processes and abundant fibrillin-2 microfibrils suggesting perturbation of a developmental expression switch. WMS mice have increased skeletal muscle mass and more myofibres, which is likely a consequence of an altered skeletal myogenesis. These results correlated with expression data showing down regulation of Growth differentiation factor (GDF8) and Bone Morphogenetic Protein (BMP) growth factor genes. In addition, the mitochondria in skeletal muscle are larger with irregular shape coupled with increased phospho-p38 mitogen-activated protein kinase (MAPK) suggesting muscle remodelling. Our data indicate that decreased SMAD1/5/8 and increased p38/MAPK signalling are associated with ADAMTS10-induced WMS. This model will allow further studies of the disease mechanism to facilitate the development of therapeutic interventions.


Asunto(s)
Proteínas ADAMTS/genética , Modelos Animales de Enfermedad , Microfibrillas/metabolismo , Mutación , Transducción de Señal , Síndrome de Weill-Marchesani/metabolismo , Proteínas ADAMTS/metabolismo , Animales , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Transgénicos , Proteínas Smad Reguladas por Receptores/metabolismo , Síndrome de Weill-Marchesani/genética
19.
Small ; 16(47): e2002200, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33140911

RESUMEN

Embedding the functional nanostructures into a lightweight nanocarbon framework is very promising for developing high performance advanced electrodes for rechargeable batteries. Here, to realize workable capacity, core-shell (FeSe2 /C) nanostructures are embedded into carbon nanotube (CNT) framework via a facile wet-chemistry approach accompanied by thermally induced selenization. The CNT framework offers 3D continuous routes for electronic/ionic transfer, while macropores provide adequate space for high mass loading of FeSe2 /C. However, the carbon shell not only creates a solid electronic link among CNTs and FeSe2 but also improves the diffusivity of sodium ions into FeSe2 , as well as acts as a buffer cushion to accommodate the volume variations. These unique structural features of CNT/FeSe2 /C make it an excellent host for sodium storage with a capacity retention of 546 mAh g-1 even after 100 cycles at 100 mA g-1 . Moreover, areal and volumetric capacities of 5.06 mAh cm-2 and 158 mAh cm-3 are also achieved at high mass loading 16.9 mg cm-2 , respectively. The high performance of multi-benefited engineered structure makes it a potential candidate for secondary ion batteries, while its easy synthesis makes it extendable to further complex structures with other morphologies (such as nanorods, nanowires, etc.) to meet the high energy demands.

20.
Bioinformatics ; 35(13): 2283-2290, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30481257

RESUMEN

MOTIVATION: Skeletal diseases are prevalent in society, but improved molecular understanding is required to formulate new therapeutic strategies. Large and increasing quantities of available skeletal transcriptomics experiments give the potential for mechanistic insight of both fundamental skeletal biology and skeletal disease. However, no current repository provides access to processed, readily interpretable analysis of this data. To address this, we have developed SkeletalVis, an exploration portal for skeletal gene expression experiments. RESULTS: The SkeletalVis data portal provides an exploration and comparison platform for analysed skeletal transcriptomics data. It currently hosts 287 analysed experiments with 739 perturbation responses with comprehensive downstream analysis. We demonstrate its utility in identifying both known and novel relationships between skeletal expression signatures. SkeletalVis provides users with a platform to explore the wealth of available expression data, develop consensus signatures and the ability to compare gene signatures from new experiments to the analysed data to facilitate meta-analysis. AVAILABILITY AND IMPLEMENTATION: The SkeletalVis data portal is freely accessible at http://phenome.manchester.ac.uk. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Biología Computacional , Transcriptoma , Programas Informáticos
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