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1.
Methods ; 225: 100-105, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38565390

RESUMEN

The development of reliable probe technology for the detection of bisulfite (HSO3-) in situ in food and biological samples is contributing significantly to food quality and safety assurance as well as community health. In this work, a responsive probe, EHDI, is developed for ratiometric fluorescence detection of HSO3- in aqueous solution, meat samples, and living cells. The probe is designed based on the HSO3- triggered 1,4-addition of electron deficit C = C bond of EHDI. As a result of this specific 1,4-addition, the π-conjugation system was destructed, resulting in blue shifts of the emission from 687 to 440 nm and absorption from 577 to 355 nm. The probe has good water solubility, high sensitivity and selectivity, allowing it to be used for imaging of HSO3- internalization and production endogenously. The capability of probe EHDI for HSO3- was then validated by traditional HPLC technology, enabling accurately detect HSO3- in beef samples. The successful development of this probe thus offers a new tool for investigating HSO3- in situ in food and biological conditions.


Asunto(s)
Colorantes Fluorescentes , Carne , Sulfitos , Sulfitos/análisis , Sulfitos/química , Colorantes Fluorescentes/química , Animales , Humanos , Carne/análisis , Espectrometría de Fluorescencia/métodos , Bovinos , Carne Roja/análisis
2.
Nucleic Acids Res ; 51(9): 4148-4177, 2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-37094040

RESUMEN

DNA sequence composition determines the topology and stability of G-quadruplexes (G4s). Bulged G-quadruplex structures (G4-Bs) are a subset of G4s characterized by 3D conformations with bulges. Current search algorithms fail to capture stable G4-B, making their genome-wide study infeasible. Here, we introduced a large family of computationally defined and experimentally verified potential G4-B forming sequences (pG4-BS). We found 478 263 pG4-BS regions that do not overlap 'canonical' G4-forming sequences in the human genome and are preferentially localized in transcription regulatory regions including R-loops and open chromatin. Over 90% of protein-coding genes contain pG4-BS in their promoter or gene body. We observed generally higher pG4-BS content in R-loops and their flanks, longer genes that are associated with brain tissue, immune and developmental processes. Also, the presence of pG4-BS on both template and non-template strands in promoters is associated with oncogenesis, cardiovascular disease and stemness. Our G4-BS models predicted G4-forming ability in vitro with 91.5% accuracy. Analysis of G4-seq and CUT&Tag data strongly supports the existence of G4-BS conformations genome-wide. We reconstructed a novel G4-B 3D structure located in the E2F8 promoter. This study defines a large family of G4-like sequences, offering new insights into the essential biological functions and potential future therapeutic uses of G4-B.


Asunto(s)
G-Cuádruplex , Humanos , Genoma Humano/genética , Estudio de Asociación del Genoma Completo , Regiones Promotoras Genéticas , Secuencia de Bases
3.
Circulation ; 148(5): 405-425, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37409482

RESUMEN

BACKGROUND: Adeno-associated virus (AAV) has emerged as one of the best tools for cardiac gene delivery due to its cardiotropism, long-term expression, and safety. However, a significant challenge to its successful clinical use is preexisting neutralizing antibodies (NAbs), which bind to free AAVs, prevent efficient gene transduction, and reduce or negate therapeutic effects. Here we describe extracellular vesicle-encapsulated AAVs (EV-AAVs), secreted naturally by AAV-producing cells, as a superior cardiac gene delivery vector that delivers more genes and offers higher NAb resistance. METHODS: We developed a 2-step density-gradient ultracentrifugation method to isolate highly purified EV-AAVs. We compared the gene delivery and therapeutic efficacy of EV-AAVs with an equal titer of free AAVs in the presence of NAbs, both in vitro and in vivo. In addition, we investigated the mechanism of EV-AAV uptake in human left ventricular and human induced pluripotent stem cell-derived cardiomyocytes in vitro and mouse models in vivo using a combination of biochemical techniques, flow cytometry, and immunofluorescence imaging. RESULTS: Using cardiotropic AAV serotypes 6 and 9 and several reporter constructs, we demonstrated that EV-AAVs deliver significantly higher quantities of genes than AAVs in the presence of NAbs, both to human left ventricular and human induced pluripotent stem cell-derived cardiomyocytes in vitro and to mouse hearts in vivo. Intramyocardial delivery of EV-AAV9-sarcoplasmic reticulum calcium ATPase 2a to infarcted hearts in preimmunized mice significantly improved ejection fraction and fractional shortening compared with AAV9-sarcoplasmic reticulum calcium ATPase 2a delivery. These data validated NAb evasion by and therapeutic efficacy of EV-AAV9 vectors. Trafficking studies using human induced pluripotent stem cell-derived cells in vitro and mouse hearts in vivo showed significantly higher expression of EV-AAV6/9-delivered genes in cardiomyocytes compared with noncardiomyocytes, even with comparable cellular uptake. Using cellular subfraction analyses and pH-sensitive dyes, we discovered that EV-AAVs were internalized into acidic endosomal compartments of cardiomyocytes for releasing and acidifying AAVs for their nuclear uptake. CONCLUSIONS: Together, using 5 different in vitro and in vivo model systems, we demonstrate significantly higher potency and therapeutic efficacy of EV-AAV vectors compared with free AAVs in the presence of NAbs. These results establish the potential of EV-AAV vectors as a gene delivery tool to treat heart failure.


Asunto(s)
Vesículas Extracelulares , Células Madre Pluripotentes Inducidas , Humanos , Ratones , Animales , Dependovirus/genética , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/genética , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Vectores Genéticos , Células Madre Pluripotentes Inducidas/metabolismo , Anticuerpos Neutralizantes , Vesículas Extracelulares/metabolismo
4.
J Am Chem Soc ; 146(20): 13709-13713, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38738955

RESUMEN

G-Quadruplex (G4) structures formed by guanine-rich DNA and RNA sequences are implicated in various biological processes. Understanding the mechanisms by which proteins recognize G4 structures is crucial for elucidating their functional roles. Here we present the X-ray crystal structure of an ankyrin protein bound to a parallel G4 structure. Our findings reveal a new specific recognition mode in which a bundle of α-helices and loops of the ankyrin form a flat surface to stack on the G-tetrad core. The protein employs a combination of hydrogen bonds and hydrophobic contacts to interact with the G4, and electrostatic interaction is used to enhance the binding affinity. This binding mechanism provides valuable insights into understanding G4 recognition by proteins.


Asunto(s)
Ancirinas , G-Cuádruplex , Modelos Moleculares , Ancirinas/química , Cristalografía por Rayos X , Humanos , Unión Proteica , Enlace de Hidrógeno
5.
Methods ; 214: 1-7, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37075873

RESUMEN

Increasing awareness of the health and environment impacts of the antibiotics misuse or overuse, such as tetracycline (TC) in treatment or prevention of infections and diseases, has driven the development of robust methods for their detection in biological, environmental and food systems. In this work, we report the development of a new europium(III) complex functionalized silica nanoprobe (SiNPs-Eu3+) for highly sensitive and selective detection of TC residue in aqueous solution and food samples (milk and meat). The nanoprobe is developed by immobilization of Eu3+ ion onto the surface of silica nanoparticles (SiNPs) as the emitter and TC recognition unit. The ß-diketone configuration of TC can further coordinate with Eu3+ steadily on the surface of nanoprobe, facilitating the absorption of light excitation for Eu3+ emitter activation and luminescence "off-on" response. The dose-dependent luminescence enhancement of SiNPs-Eu3+ nanoprobe exhibits good linearities, allowing the quantitative detection of TC. The SiNPs-Eu3+ nanoprobe shows high sensitivity and selectivity for TC detection in buffer solution. Time resolved luminescence analysis enables the elimination of autofluorescence and light scattering for highly sensitive detection of TC in milk and pork mince with high accuracy and precision. The successful development of SiNPs-Eu3+ nanoprobe is anticipated to provide a rapid, economic, and robust approach for TC detection in real world samples.


Asunto(s)
Europio , Luminiscencia , Europio/análisis , Europio/química , Dióxido de Silicio , Tetraciclina/análisis , Tetraciclina/química , Antibacterianos
6.
J Chem Phys ; 160(7)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38364012

RESUMEN

We extend the force-level elastically collective nonlinear Langevin equation theory to treat the spatial gradients of the alpha relaxation time and glass transition temperature, and the corresponding film-averaged quantities, to the geometrically asymmetric case of finite thickness supported films with variable fluid-substrate coupling. The latter typically nonuniversally slows down motion near the solid-liquid interface as modeled via modification of the surface dynamic free energy caging constraints that are spatially transferred into the film and which compete with the accelerated relaxation gradient induced by the vapor interface. Quantitative applications to the foundational hard sphere fluid and a polymer melt are presented. The strength of the effective fluid-substrate coupling has very large consequences for the dynamical gradients and film-averaged quantities in a film thickness and thermodynamic state dependent manner. The interference of the dynamical gradients of opposite nature emanating from the vapor and solid interfaces is determined, including the conditions for the disappearance of a bulk-like region in the film center. The relative importance of surface-induced modification of local caging vs the generic truncation of the long range collective elastic component of the activation barrier is studied. The conditions for the accuracy and failure of a simple superposition approximation for dynamical gradients in thin films are also determined. The emergence of near substrate dead layers, large gradient effects on film-averaged response functions, and a weak non-monotonic evolution of dynamic gradients in thick and cold films are briefly discussed. The connection of our theoretical results to simulations and experiments is briefly discussed, as is the extension to treat more complex glass-forming systems under nanoconfinement.

7.
Proc Natl Acad Sci U S A ; 118(31)2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34326262

RESUMEN

Molecular, polymeric, colloidal, and other classes of liquids can exhibit very large, spatially heterogeneous alterations of their dynamics and glass transition temperature when confined to nanoscale domains. Considerable progress has been made in understanding the related problem of near-interface relaxation and diffusion in thick films. However, the origin of "nanoconfinement effects" on the glassy dynamics of thin films, where gradients from different interfaces interact and genuine collective finite size effects may emerge, remains a longstanding open question. Here, we combine molecular dynamics simulations, probing 5 decades of relaxation, and the Elastically Cooperative Nonlinear Langevin Equation (ECNLE) theory, addressing 14 decades in timescale, to establish a microscopic and mechanistic understanding of the key features of altered dynamics in freestanding films spanning the full range from ultrathin to thick films. Simulations and theory are in qualitative and near-quantitative agreement without use of any adjustable parameters. For films of intermediate thickness, the dynamical behavior is well predicted to leading order using a simple linear superposition of thick-film exponential barrier gradients, including a remarkable suppression and flattening of various dynamical gradients in thin films. However, in sufficiently thin films the superposition approximation breaks down due to the emergence of genuine finite size confinement effects. ECNLE theory extended to treat thin films captures the phenomenology found in simulation, without invocation of any critical-like phenomena, on the basis of interface-nucleated gradients of local caging constraints, combined with interfacial and finite size-induced alterations of the collective elastic component of the structural relaxation process.

8.
Sensors (Basel) ; 24(3)2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38339704

RESUMEN

This paper introduces an approach to the automated measurement and analysis of dairy cows using 3D point cloud technology. The integration of advanced sensing techniques enables the collection of non-intrusive, precise data, facilitating comprehensive monitoring of key parameters related to the health, well-being, and productivity of dairy cows. The proposed system employs 3D imaging sensors to capture detailed information about various parts of dairy cows, generating accurate, high-resolution point clouds. A robust automated algorithm has been developed to process these point clouds and extract relevant metrics such as dairy cow stature height, rump width, rump angle, and front teat length. Based on the measured data combined with expert assessments of dairy cows, the quality indices of dairy cows are automatically evaluated and extracted. By leveraging this technology, dairy farmers can gain real-time insights into the health status of individual cows and the overall herd. Additionally, the automated analysis facilitates efficient management practices and optimizes feeding strategies and resource allocation. The results of field trials and validation studies demonstrate the effectiveness and reliability of the automated 3D point cloud approach in dairy farm environments. The errors between manually measured values of dairy cow height, rump angle, and front teat length, and those calculated by the auto-measurement algorithm were within 0.7 cm, with no observed exceedance of errors in comparison to manual measurements. This research contributes to the burgeoning field of precision livestock farming, offering a technological solution that not only enhances productivity but also aligns with contemporary standards for sustainable and ethical animal husbandry practices.


Asunto(s)
Nube Computacional , Aprendizaje Profundo , Femenino , Bovinos , Animales , Reproducibilidad de los Resultados , Industria Lechera/métodos , Tecnología
9.
Phys Chem Chem Phys ; 25(13): 9073-9082, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36919786

RESUMEN

Beryllium is a vital alkaline-earth metal for plasma physics, space science, and nuclear technology. Unfortunately, its accurate phase diagram is clouded by many controversial results, even though solid beryllium can only exist with hcp or bcc crystalline structures. Herein, we offer a simple quantum-statistical solution to the above problem. Our core idea is to develop the moment expansion technique to determine the Helmholtz free energy under extreme conditions. This strategy helps elucidate the underlying correlation among symmetric characteristics, vibrational excitations, and physical stabilities. In particular, our analyses reveal that the appearance of anharmonic effects forcefully straightens up the hcp-bcc boundary. This phenomenon explains why it has been difficult to detect bcc signatures via diamond-anvil-cell measurements. Besides, we modify the work-heat equivalence principle to quickly obtain the high-pressure melting profile from the room-temperature equation of state. The hcp-bcc-liquid triple point of beryllium is found at 165 GPa and 4559 K. Our theoretical findings agree excellently with cutting-edge ab initio simulations adopting the phonon quasiparticle method and the thermodynamic integration. Finally, we consider the principal Hugoniot curve and its secondary branches to explore the behaviors of beryllium under shock compression. Our predictions would be advantageous for designing inertial-confinement-fusion experiments.

10.
Nucleic Acids Res ; 49(13): 7588-7601, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34214172

RESUMEN

Human telomeres are composed of GGGTTA repeats and interspersed with variant repeats. The GGGCTA variant motif was identified in the proximal regions of human telomeres about 10 years ago and was shown to display a length-dependent instability. In parallel, a structural study showed that four GGGCTA repeats folded into a non-canonical G-quadruplex (G4) comprising a Watson-Crick GCGC tetrad. It was proposed that this non-canonical G4 might be an additional obstacle for telomere replication. In the present study, we demonstrate that longer GGGCTA arrays fold into G4 and into hairpins. We also demonstrate that replication protein A (RPA) efficiently binds to GGGCTA repeats structured into G4 but poorly binds to GGGCTA repeats structured into hairpins. Our results (along with results obtained with a more stable variant motif) suggest that GGGCTA hairpins are at the origin of GGGCTA length-dependent instability. They also suggest, as working hypothesis, that failure of efficient binding of RPA to GGGCTA structured into hairpins might be involved in the mechanism of GGGCTA array instability. On the basis of our present and past studies about telomeric G4 and their interaction with RPA, we propose an original point of view about telomeric G4 and the evolution of telomeric motifs.


Asunto(s)
Proteína de Replicación A/metabolismo , Telómero/química , ADN/química , G-Cuádruplex , Humanos , Conformación de Ácido Nucleico , Motivos de Nucleótidos , Oligonucleótidos/química , Secuencias Repetitivas de Ácidos Nucleicos , Complejo Shelterina , Telómero/metabolismo , Proteínas de Unión a Telómeros/metabolismo
11.
Nucleic Acids Res ; 49(3): 1724-1736, 2021 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-33503265

RESUMEN

G-quadruplex (G4) DNA structures with a left-handed backbone progression have unique and conserved structural features. Studies on sequence dependency of the structures revealed the prerequisites and some minimal motifs required for left-handed G4 formation. To extend the boundaries, we explore the adaptability of left-handed G4s towards the existence of bulges. Here we present two X-ray crystal structures and an NMR solution structure of left-handed G4s accommodating one, two and three bulges. Bulges in left-handed G4s show distinct characteristics as compared to those in right-handed G4s. The elucidation of intricate structural details will help in understanding the possible roles and limitations of these unique structures.


Asunto(s)
ADN/química , G-Cuádruplex , Cristalografía por Rayos X , Modelos Moleculares , Resonancia Magnética Nuclear Biomolecular , Motivos de Nucleótidos , Azúcares/química
12.
Molecules ; 28(6)2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36985798

RESUMEN

Kakadu plum (Terminalia ferdinandiana), endemic to Australia, is growing in popularity due to its high levels of vitamin C and strong antioxidant properties. In this study, Kakadu plum fruit powder was used as a functional food ingredient with other plant materials to develop value-added products to enhance their nutritional and commercial value. The present study determined the bioactive properties of nine products, including three Kakadu plum fruit powder samples produced from different processing batches and five Kakadu plum-blended products. Vitamin C, the total phenolic content, and the ellagic acid content were determined. Bioactive properties such as antioxidant, antidiabetic, and antimicrobial assays were also performed. Cytotoxicity was tested to obtain more specific product information regarding food safety. Kakadu plum-blended products showed lower cytotoxicity and lower bioactive properties (antioxidant and antibacterial activities) in comparison to Kakadu plum powder. However, overall, most of the bioactive properties were shown to be higher in the blends when compared with the commercial blueberry powder as a benchmark antioxidant product. Therefore, there is great potential for Kakadu plum to contribute to the growing functional food and ingredient markets.


Asunto(s)
Antioxidantes , Prunus domestica , Antioxidantes/farmacología , Polvos , Ácido Ascórbico , Fenoles/farmacología , Fenoles/análisis , Vitaminas , Frutas/química
13.
Molecules ; 28(4)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36838596

RESUMEN

Pleiogynium timoriense, commonly known as Burdekin plum (BP), is among many Australian native plants traditionally used by Indigenous people. However, only limited information is available on the nutritional and sensory quality of BP grown in Australia as well as its changes during storage. Therefore, this study evaluated the quality of BP during one week of ambient storage (temperature 21 °C, humidity 69%). Proximate analysis revealed a relatively high dietary fiber content in BP (7-10 g/100 g FW). A significant reduction in fruit weight and firmness (15-30% and 60-90%, respectively) with distinguishable changes in flesh color (ΔE > 3) and an increase in total soluble solids (from 11 to 21 °Brix) could be observed during storage. The vitamin C and folate contents in BP ranged from 29 to 59 mg/100g FW and 0.3 to 5.9 µg/100g FW, respectively, after harvesting. A total phenolic content of up to 20 mg GAE/g FW and ferric reducing antioxidant power of up to 400 µmol Fe2+/g FW in BP indicate a strong antioxidant capacity. In total, 34 individual phenolic compounds were tentatively identified in BP including cyanidin 3-galactoside, ellagic acid and gallotannins as the main phenolics. Principle component analysis (PCA) of the quantified phenolics indicated that tree to tree variation had a bigger impact on the phenolic composition of BP than ambient storage. Sensory evaluation also revealed the diversity in aroma, appearance, texture, flavor and aftertaste of BP. The results of this study provide crucial information for consumers, growers and food processors.


Asunto(s)
Anacardiaceae , Prunus domestica , Humanos , Antioxidantes , Australia , Ácido Ascórbico , Frutas
14.
Molecules ; 28(10)2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37241743

RESUMEN

Halophytes are considered emerging functional foods as they are high in protein, minerals, and trace elements, although studies investigating halophyte digestibility, bioaccessibility, and intestinal absorption are limited. Therefore, this study investigated the in vitro protein digestibility, bioaccessibility and intestinal absorption of minerals and trace elements in saltbush and samphire, two important Australian indigenous halophytes. The total amino acid contents of samphire and saltbush were 42.5 and 87.3 mg/g DW, and even though saltbush had a higher total protein content overall, the in vitro digestibility of samphire protein was higher than the saltbush protein. The in vitro bioaccessibility of Mg, Fe, and Zn was higher in freeze-dried halophyte powder compared to the halophyte test food, suggesting that the food matrix has a significant impact on mineral and trace element bioaccessibility. However, the samphire test food digesta had the highest intestinal Fe absorption rate, whereas the saltbush digesta exhibited the lowest (37.7 vs. 8.9 ng/mL ferritin). The present study provides crucial data about the digestive "fate" of halophyte protein, minerals, and trace elements and increases the understanding of these underutilized indigenous edible plants as future functional foods.


Asunto(s)
Plantas Tolerantes a la Sal , Oligoelementos , Australia , Absorción Intestinal , Minerales , Plantas Tolerantes a la Sal/química , Oligoelementos/análisis
15.
Am J Respir Cell Mol Biol ; 66(3): 312-322, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34861136

RESUMEN

Respiratory syncytial virus (RSV)-induced immunopathogenesis and disease severity in neonatal mice and human infants have been related to elevated pulmonary IL-33. Thus, targeting IL-33 has been suggested as a potential therapy for respiratory viral infections. Yet, the regulatory mechanisms on IL-33 during early life remain unclear. Here, using a neonatal mouse model of RSV, we demonstrate that IL-1ß positively regulates but is not required for RSV-induced expression of pulmonary IL-33 in neonatal mice early after the initial infection. Exogenous IL-1ß upregulates RSV-induced IL-33 expression by promoting the proliferation of IL-33+ lung epithelial stem/progenitor cells. These cells are exclusively detected in RSV-infected neonatal rather than adult mice, partially explaining the IL-1ß-independent IL-33 expression in RSV-infected adult mice. Furthermore, IL-1ß aggravates IL-33-mediated T-helper cell type 2-biased immunopathogenesis upon reinfection. Collectively, our study demonstrates that IL-1ß exacerbates IL-33-mediated RSV immunopathogenesis by promoting the proliferation of IL-33+ epithelial stem/progenitor cells in early life.


Asunto(s)
Interleucina-1beta/farmacología , Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Animales , Humanos , Interleucina-33 , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Infecciones por Virus Sincitial Respiratorio/patología , Células Madre/patología
16.
Lancet ; 397(10284): 1554-1563, 2021 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-33894833

RESUMEN

BACKGROUND: The use of intracytoplasmic sperm injection has increased substantially worldwide, primarily in couples with non-male factor infertility. However, there is a paucity of evidence from randomised trials supporting this approach compared with conventional in-vitro fertilisation (IVF). We aimed to investigate whether intracytoplasmic sperm injection would result in a higher livebirth rate compared with conventional IVF. METHODS: This open-label, multicentre, randomised trial was done at two IVF centres in Ho Chi Minh City, Vietnam (IVFMD, My Duc Hospital and IVFAS, An Sinh Hospital). Eligible couples were aged at least 18 years and the male partner's sperm count and motility (progressive motility) were normal based on WHO 2010 criteria. Couples had to have undergone two or fewer previous conventional IVF or intracytoplasmic sperm injection attempts, have used an antagonist protocol for ovarian stimulation, and agree to have two or fewer embryos transferred. Couples were randomly assigned (1:1) to undergo either intracytoplasmic sperm injection or conventional IVF, using block randomisation with variable block size of 2, 4, or 8 and a telephone-based central randomisation method. The computer-generated randomisation list was prepared by an independent statistician who had no other involvement in the study. Embryologists and couples were not masked to study groups because of the type of interventions and differences in hospital fees, but clinicians performing embryo transfer were unaware of study group allocation. The primary outcome was livebirth after the first embryo transfer from the initiated cycle. Analyses were done on an intention-to-treat basis. The trial is registered with ClinicalTrials.gov, NCT03428919. FINDINGS: Between March 16, 2018, and Aug 12, 2019, we randomly assigned 1064 couples to intracytoplasmic sperm injection (n=532) or conventional IVF (n=532). Livebirth after the first embryo transfer from the initiated cycle occurred in 184 (35%) of 532 couples randomly assigned to intracytoplasmic sperm injection and in 166 (31%) of 532 couples randomly assigned to conventional IVF (absolute difference 3·4%, 95% CI -2·4 to 9·2; risk ratio [RR] 1·11, 95% CI 0·93 to 1·32; p=0·27). 29 (5%) couples in the intracytoplasmic sperm injection group and 34 (6%) couples in the conventional IVF group had fertilisation failure (absolute difference -0·9%, -4·0 to 2·1, RR 0·85, 95% CI 0·53 to 1·38; p=0·60). INTERPRETATION: In couples with infertility in whom the male partner has a normal total sperm count and motility, intracytoplasmic sperm injection did not improve the livebirth rate compared with conventional IVF. Our results challenge the value of the routine use of intracytoplasmic sperm injection in assisted reproduction techniques for this population. FUNDING: My Duc Hospital and Merck Sharp and Dohme.


Asunto(s)
Fertilización In Vitro/efectos adversos , Infertilidad/terapia , Técnicas Reproductivas Asistidas/estadística & datos numéricos , Inyecciones de Esperma Intracitoplasmáticas/efectos adversos , Adulto , Transferencia de Embrión/métodos , Femenino , Fertilización In Vitro/métodos , Humanos , Análisis de Intención de Tratar/métodos , Nacimiento Vivo/epidemiología , Masculino , Inducción de la Ovulación/métodos , Embarazo , Resultado del Embarazo , Técnicas Reproductivas Asistidas/tendencias , Recuento de Espermatozoides/métodos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Motilidad Espermática/fisiología , Vietnam/epidemiología
17.
Biochem Biophys Res Commun ; 613: 153-158, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35561583

RESUMEN

93del is a 16-nucleotide G-quadruplex-forming aptamer which can inhibit the activity of the HIV-1 integrase enzyme at nanomolar concentration. Previous structural analyses of 93del using NMR spectroscopy have shown that the aptamer forms an interlocked G-quadruplex structure in K+ solution. Due to its exceptional stability and unique topology, 93del has been used in many different studies involving DNA G-quadruplexes, such as DNA aptamer and multimer design, as well as DNA fluorescence research. To gain further insights on the structure of this unique aptamer, we have determined several high-resolution crystal structures of 93del and its variants. While confirming the overall dimeric interlocked G-quadruplex folding topology previously determined by NMR, our results reveal important detailed structural information, particularly the formation of a water-mediated A•G•G•G•G pentad. These insights allow us to better understand the formation of various structural elements in G-quadruplexes and should be useful for designing and manipulating G-quadruplex scaffolds with desired properties.


Asunto(s)
Aptámeros de Nucleótidos , G-Cuádruplex , Integrasa de VIH , Aptámeros de Nucleótidos/química , Integrasa de VIH/metabolismo , Agua
18.
Biochem Biophys Res Commun ; 610: 113-118, 2022 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-35462091

RESUMEN

In the neurodegenerative disorders amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), expansion of the G4C2 hexanucleotide repeat in the gene C9orf72 is a most common known cause of the disease. Here we use atomic force microscopy (AFM) and gel electrophoresis to visualize the formation of higher-order structures by RNA G4C2 repeats in physiologically relevant conditions. For the RNA sequence r[G4C2G4], we observed G-wires with left-handed undulating features of 4.4-nm periodicity and a uniform height which is consistently higher than that of a duplex B-DNA. These higher-order structures were not degraded fully when treated with a mixture of RNase A and RNase T1. Similarly, higher-order structures were observed for sequences containing three or four G4C2 repeats, pointing towards their potential formation in longer sequence contexts. Our observations suggest that RNA G-quadruplex blocks and G-wires can accumulate in cells containing G4C2 repeat transcripts.


Asunto(s)
Esclerosis Amiotrófica Lateral , Demencia Frontotemporal , Esclerosis Amiotrófica Lateral/genética , Proteína C9orf72/química , Proteína C9orf72/genética , Expansión de las Repeticiones de ADN , Demencia Frontotemporal/genética , Humanos , ARN/genética
19.
J Autoimmun ; 131: 102857, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35780036

RESUMEN

Dysregulated T-cell activation is a hallmark of several autoimmune diseases such as rheumatoid arthritis (RA) and multiple sclerosis (MS). The lymphocyte cytosolic protein 2 (LCP2), also known as SLP-76, is essential for the development and activation of T cells. Despite the critical role of LCP2 in T-cell activation and the need for developing drugs that modify T-cell activation, no LCP2 inhibitors have been developed. This can be explained by the "undruggable" nature of LCP2, lacking a structure permissive to standard small molecule inhibitor modalities. Here, we explored an alternative drug modality, developing antisense oligonucleotides (ASOs) targeting LCP2 mRNAs, and evaluated its activity in modulating T-cell activation. We identified a set of 3' UTR targeting LCP2 ASOs, which knocked down LCP2 in a human T-cell line and primary human T cells and found that these suppressed T-cell receptor mediated activation. We also found that the ASOs suppressed FcεR1-mediated mast cell activation, in line with the role of LCP2 in mast cells. Taken together, our data provide examples of how immunomodulatory ASOs that interfere with undruggable targets can be developed and propose that such drug modalities can be used to treat autoimmune diseases.


Asunto(s)
Enfermedades Autoinmunes , Oligonucleótidos Antisentido , Línea Celular , Humanos , Activación de Linfocitos , Oligonucleótidos Antisentido/química , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Linfocitos T
20.
Phys Chem Chem Phys ; 24(8): 4910-4915, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35137768

RESUMEN

Vacancies are prevalent point defects in crystals, but their thermal responses are elusive. Herein, we formulate a simple theoretical model to shed light on the vacancy evolution during heating. Vibrational excitations are thoroughly investigated via moment recurrence techniques in quantum statistical mechanics. On that basis, we carry out numerical analyses for Ag, Cu, and Ni with the Sutton-Chen many-body potential. Our results reveal that the well-known Arrhenius law is insufficient to describe the proliferation of vacancies. Specifically, anharmonic effects lead to a strong nonlinearity in the Gibbs energy of vacancy formation. Our physical picture is well supported by previous simulations and experiments.

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