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1.
Arch Gynecol Obstet ; 310(2): 713-718, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38871965

RESUMEN

BACKGROUND: Acute abdominal conditions during pregnancy are significant risks to maternal and fetal health, necessitating timely diagnosis and intervention. The choice of surgical approach is a major concern for obstetricians. OBJECTIVE: To evaluate the safety and efficacy of the TU-LESS procedure for acute abdomen in late pregnancy. METHODS: We retrospectively analyzed 12 patients who underwent TU-LESS for acute abdominal conditions in the third trimester from 2020 to 2023. We reviewed medical records for clinical characteristics, surgical interventions, postoperative complications, and pregnancy outcomes. RESULTS: The study included patients with a median age of 27 (range 20-35) and a BMI of 24.33 kg/m2 (range 21.34-31.96). The median gestational age at surgery was 30 weeks (range, 28 + 3-32 + 4 weeks), with surgeries lasting an average of 60 min (range, 30-163 min). Blood loss was 2-20 mL, and the median hospital stay post-surgery was 6 days (range, 2-16 days). There were no significant complications. The median time to delivery after TU-LESS was 56 days (range, 26-66 days), resulting in 8 full-term deliveries, 2 preterm cesareans, and 2 preterm vaginal deliveries. All newborns were healthy, with no fetal losses or neonatal deaths. CONCLUSION: TU-LESS, performed by experienced obstetricians and gynecologists with proper preoperative preparation, is safe and effective for managing acute abdomen in late pregnancy, without the need to delay surgery due to gestational age.


Asunto(s)
Abdomen Agudo , Complicaciones del Embarazo , Tercer Trimestre del Embarazo , Humanos , Femenino , Embarazo , Estudios Retrospectivos , Abdomen Agudo/cirugía , Abdomen Agudo/etiología , Adulto , Complicaciones del Embarazo/cirugía , Adulto Joven , Resultado del Embarazo , Edad Gestacional , Complicaciones Posoperatorias/epidemiología , Tiempo de Internación/estadística & datos numéricos
2.
J Phys Chem Lett ; 15(22): 5905-5913, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38809103

RESUMEN

The regulation of physiochemical behaviors by changing molecular weights is an important cornerstone of polymer physics. However, similar correlations between molecular weights and properties have not been discovered in inorganic ionic compounds. In this work, we prepared a calcium carbonate specimen with a semiflexible chain topology analogous to those of polymers. The molecular weights of the calcium carbonate chains, which ranged from 3400 to 54 100 Da, were directly correlated to their physiochemical behaviors, including gel point, zero shear viscosity, and plateau modulus. The calcium carbonate chains showed similar polymeric characteristics, including shear thinning, thixotropy, entropic elasticity, and viscoelasticity. These features agreed with recent theories and formulas in polymer physics textbooks. On the basis of this understanding, the mechanical properties of calcium carbonate-based gels could be altered by changing their molecular weights. This study could represent a fusion of inorganic chemistry and polymer physics with similar molecular weight-dependent behaviors and material properties, establishing an alternative pathway for designing future inorganic materials.

3.
Cell Death Dis ; 15(4): 265, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615022

RESUMEN

Antigen-specific T cell receptor-engineered T cell (TCR-T) based immunotherapy has proven to be an effective method to combat cancer. In recent years, cross-talk between the innate and adaptive immune systems may be requisite to optimize sustained antigen-specific immunity, and the stimulator of interferon genes (STING) is a promising therapeutic target for cancer immunotherapy. The level of expression or presentation of antigen in tumor cells affects the recognition and killing of tumor cells by TCR-T. This study aimed at investigating the potential of innate immune stimulation of T cells and engineered T cells to enhance immunotherapy for low-expression antigen cancer cells. We systematically investigated the function and mechanism of cross-talk between STING agonist diABZI and adaptive immune systems. We established NY-ESO-1 full knockout Mel526 cells for this research and found that diABZI activated STING media and TCR signaling pathways. In addition, the results of flow cytometry showed that antigens presentation from cancer cells induced by STING agonist diABZI also improved the affinity of TCR-T cells function against tumor cells in vitro and in vivo. Our findings revealed that diABZI enhanced the immunotherapy efficacy of TCR-T by activating STING media and TCR signaling pathways, improving interferon-γ expression, and increasing antigens presentation of tumor cells. This indicates that STING agonist could be used as a strategy to promote TCR-T cancer immunotherapy.


Asunto(s)
Neoplasias , Linfocitos T , Presentación de Antígeno , Anticuerpos , Citometría de Flujo , Receptores de Antígenos de Linfocitos T , Neoplasias/terapia
5.
Nat Nanotechnol ; 19(6): 716-717, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38548909
6.
Nat Nanotechnol ; 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499860

RESUMEN

Bone is the most common site of metastasis, and although low proliferation and immunoediting at the early stage make existing treatment modalities less effective, the microenvironment-inducing behaviour could be a target for early intervention. Here we report on a spatiotemporal coupling interaction between tumour cells and osteoclasts, and named the tumour-associated osteoclast 'tumasteoclast'-a subtype of osteoclasts in bone metastases induced by tumour-migrasome-mediated cytoplasmic transfer. We subsequently propose an in situ decoupling-killing strategy in which tetracycline-modified nanoliposomes encapsulating sodium bicarbonate and sodium hydrogen phosphate are designed to specifically release high concentrations of hydrogen phosphate ions triggered by tumasteoclasts, which depletes calcium ions and forms calcium-phosphorus crystals. This can inhibit the formation of migrasomes for decoupling and disrupt cell membrane for killing, thereby achieving early prevention of bone metastasis. This study provides a research model for exploring tumour cell behaviour in detail and a proof-of-concept for behaviour-targeting strategy.

7.
Mar Life Sci Technol ; 6(1): 102-114, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38433970

RESUMEN

Marine microorganisms have long been recognized as potential sources for drug discovery. Griseofulvin was one of the first antifungal natural products and has been used as an antifungal agent for decades. In this study, 12 new griseofulvin derivatives [(±)-1-2, (+)-3, (±)-4, 10-12, and 14-15] and two new griseofulvin natural products (9 and 16) together with six known analogues [(-)-3, 5-8, and 13] were isolated from the mangrove-derived fungus Nigrospora sp. QQYB1 treated with 0.3% NaCl or 2% NaBr in rice solid medium. Their 2D structures and absolute configurations were established by extensive spectroscopic analysis (1D and 2D NMR, HRESIMS), ECD spectra, computational calculation, DP4 + analysis, and X-ray single-crystal diffraction. Compounds 1-4 represent the first griseofulvin enantiomers with four absolute configurations (2S, 6'S; 2R, 6'R; 2S, 6'R; 2R, 6'S), and compounds 9-12 represent the first successful production of brominated griseofulvin derivatives from fungi via the addition of NaBr to the culture medium. In the antifungal assays, compounds 6 and 9 demonstrated significant inhibitory activities against the fungi Colletotrichum truncatum, Microsporum gypseum, and Trichophyton mentagrophyte with inhibition zones varying between 28 and 41 mm (10 µg/disc). The structure-activity relationship (SAR) was analyzed, which showed that substituents at C-6, C-7, C-6' and the positions of the carbonyl and double bond of griseofulvin derivatives significantly affected the antifungal activity. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00210-0.

8.
Front Bioeng Biotechnol ; 12: 1344964, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38344290

RESUMEN

Bamboo is considered a renewable energy bioresource for solving the energy crisis and climate change. Dendrocalamus branddisii (DB) was first subjected to sulfomethylation reaction at 95°C for 3 h, followed by Fenton oxidation pretreatment at 22°C for 24 h. The synergistic effect of combined pretreatment dramatically improved enzymatic digestibility efficiency, with maximum yield of glucose and ethanol content of 71.11% and 16.47 g/L, respectively, increased by 4.7 and 6.11 time comparing with the single Fenton oxidation pretreatment. It was found that the hydrophobicity of substrate, content of surface lignin, degree of polymerization, and specific surface area have significant effects on the increase of enzymatic saccharification efficiency. It also revealed that sulfomethylation pre-extraction can improve the hydrophilicity of lignin, leading to the lignin dissolution, which was beneficial for subsequent Fenton pretreatment of bamboo biomass. This work provides some reference for Fenton oxidation pretreatment of bamboo biomass, which can not only promote the utilization of bamboo in southwest China, but also enhances the Fenton reaction in the bamboo biorefinery.

9.
J Phys Chem Lett ; 15(9): 2624-2631, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38420912

RESUMEN

As a result of the non-directionality of ionic bonds, oppositely charged ions always assemble into closely packed clusters or crystals rather than linear structured ionic species. Here, we generated a series of linear calcium carbonate chains, (Ca2+CO32-)n, with an orientated directionality of the ionic interactions. The formation of these ionic chains with long-range ordered ionic interactions was originally induced by the dipole orientation of the ions and subsequently preserved by capping agents. According to the appropriately established folding-capping model, rational control of the capping effect can regulate the length of the (Ca2+CO32-)n chain within 100 nm, corresponding to n ≤ 250. Our discovery overturns the current understanding of ionic bonding in chemistry and opens a way to control the assembly of inorganic ions at molecular scale, pushing forward a fusion of molecular compounds and ionic compounds that share similar topological control.

10.
Cancer Cell Int ; 24(1): 64, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336680

RESUMEN

BACKGROUND: Esophageal cancer (EC) is a global canker notorious for causing high mortality due to its relentless incidence rate, convoluted with unyielding recurrence and metastasis. However, these intricacies of EC are associated with an immoderate expression of NY-ESO-1 antigen, presenting a lifeline for adoptive T cell therapy. We hypothesized that naturally isolated higher-affinity T cell receptors (TCRs) that bind to NY-ESO-1 would allow T lymphocytes to target EC with a pronounced antitumor response efficacy. Also, targeting TRPV2, which is associated with tumorigenesis in EC, creates an avenue for dual-targeted therapy. We exploited the dual-targeting antitumor efficacy against EC. METHODS: We isolated antigen-specific TCRs (asTCRs) from a naive library constructed with TCRs obtained from enriched cytotoxic T lymphocytes. The robustness of our asTCRs and their TCR-T cell derivatives, Tranilast (TRPV2 inhibitor), and their bivalent treatment were evaluated with prospective cross-reactive human-peptide variants and tumor cells. RESULTS: Our study demonstrated that our naive unenhanced asTCRs and their TCR-Ts perpetuated their cognate HLA-A*02:01/NY-ESO-1(157-165) specificity, killing varying EC cells with higher cytotoxicity compared to the known affinity-enhanced TCR (TCRe) and its wild-type (TCR0) which targets the same NY-ESO-1 antigen. Furthermore, the TCR-Ts and Tranilast bivalent treatment showed superior EC killing compared to any of their monovalent treatments of either TCR-T or Tranilast. CONCLUSION: Our findings suggest that dual-targeted immunotherapy may have a superior antitumor effect. Our study presents a technique to evolve novel, robust, timely therapeutic strategies and interventions for EC and other malignancies.

11.
Nat Prod Res ; : 1-7, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38251853

RESUMEN

A new phenylspirodrimane derivative named stachybotrysin A (1), together with four known analogues (2-5) were isolated and purified from the solid culture of the deep-sea-derived Stachybotrys chartarum FS705. Their structures were determined by comprehensive spectroscopic analysis and the absolute configuration was evaluated by theoretical ECD calculations. Compounds 1-5 were evaluated for their cytotoxic, antibacterial and α-glucosidase inhibitory activities. The results showed that compound 2 displayed mild cytotoxicity with IC50 values in the range of 8.88 ∼ 22.73 µM against four human tumour cell lines, SF-268, MCF-7, HepG-2, and A549. Compound 1 showed strong α-glucosidase inhibitory activity with an IC50 value of 20.68 µM. Compounds 4 and 5 exhibited weak antibacterial activity against Bacillus subtilis.

12.
Nat Prod Res ; 38(4): 594-600, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-36938638

RESUMEN

Two new compounds (R)-6-((8S)-hydroxypropyl)-2-methyl-5,6-dihydro-4H-pyran-4-one (1) and (R)-6-((8R)-hydroxypropyl)-2-methyl-5,6-dihydro-4H-pyran-4-one (2), together with four known compounds were isolated from the marine-derived fungus Cladosporium halotolerans FS702. The structures of these compounds were determined on the basis of extensive spectroscopic analysis including 1D/2D NMR, IR, UV, HRESIMS, ECD calculations as well as the modified Mosher's method. Cytotoxic assay results showed that compound 2 had significant cytotoxic activity against SF-268, MCF-7, HepG-2, and A549 cells lines with IC50 values of 0.16, 0.47, 0.33 and 0.23 µM, respectively.


Asunto(s)
Antineoplásicos , Pironas , Línea Celular Tumoral , Pironas/farmacología , Antineoplásicos/química , Hongos/química , Cladosporium/química , Estructura Molecular
13.
Adv Mater ; 36(3): e2308017, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38009645

RESUMEN

Alloys often combine different metals to generate superior mechanical properties. However, it is challenging to prepare high mechanical strength minerals with similar strategies. Using calcium carbonate (CaC) and calcium phosphate (CaP) as examples, this work synthesizes a group of compounds with the chemical formulas Ca(CO3 )x (PO4 )2(1- x )/3 (0 < x < 1, CaCPs) by cross-linking ionic oligomers. Unlike mixtures, these CaCPs exhibit a single temperature for the phase transition from amorphous to crystallized CaC (calcite) and CaP (hydroxyapatite). By heat-induced synchronous crystallization, dual-phase CaC/CaP with continuous crystallized boundaries are resembled to alloy-like minerals (ALMs). The mechanical properties of the ALMs are adjusted by tailoring their chemical compositions to reach a hardness of 5.6 GPa, which exceed those of control calcite and hydroxyapatite samples by 430% and 260%, respectively. This strategy expands the chemical scope of inorganic materials and holds promise for preparing high-performance minerals.

14.
Chem Biodivers ; 20(12): e202301512, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37921566

RESUMEN

Four new phomalones A-D (1-4), together with five known analogues (5-9) were isolated from the deep-sea-derived fungus Trichobotrys effuse FS522. Their structures of the new compounds established by analysis of their NMR and HR-ESI-MS spectroscopic data, and the absolute configurations of 2 was determined by electronic circular dichroism (ECD) calculations. compounds 4, 6 and 8 substantially inhibited the production of nitric oxide (NO) with IC50 values of 4.64, 13.90, and 34.07 µM.


Asunto(s)
Ascomicetos , Antiinflamatorios/farmacología , Espectroscopía de Resonancia Magnética/métodos , Estructura Molecular , Piranos/química , Piranos/farmacología , Compuestos Heterocíclicos con 3 Anillos/química , Compuestos Heterocíclicos con 3 Anillos/farmacología
15.
Am J Transl Res ; 15(7): 4544-4557, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37560239

RESUMEN

BACKGROUND: Preterm premature rupture of membranes (PPROM) is closely associated with pathogenic microbiomes in the female reproductive tract, and can lead to neonatal septicemia. The current study aimed to investigate potential pathogenic microbiomes associated with neonatal septicemia based on DNA metagenome sequencing. METHODS: In this study, a total of 7 pregnant women with PPROM presenting neonatal septicemia (experimental group) and 3 pregnant women with normal newborns (control group) were enrolled. Vaginal secretions at admission and before parturition as well as placental tissues after parturition were collected for DNA metagenome sequencing using whole genome shotgun method on the Illumina NovaSeq/HiSeq platform. Raw data were processed by BioBakery workflow, and MetaPhlAn4 was implemented for qualitative and quantitative analyses of microbiome. Lactobacillus crispatus, Gardneralla vaginalis, Fannyhessea vaginae and Streptococcus suis were specifically detected from the experimental group. The two groups were compared using Student's t-tests. RESULTS: The indexes of Chao1 (P=0.00028/P=0.00072), abundance-based coverage estimator (ACE, P=0.00059/P=0.00026), Shannon (P=0.036/P=0.0065) and Simpson (P=0.007/P=0.041) in the experimental group were increased at admission and before parturition as compared with the control group. Several microbiomes, such as Lactobacillus crispatus, Gardneralla vaginalis, Fannyhessea vaginae and Streptococcus suis, were specifically detected in the experimental group. Notably, Gardnerella vaginalis and Streptococcus gallolyticus were identified from the vaginal secretions and placenta tissues of women with neonatal septicemia. Moreover, nucleic acid synthesis and carbohydrate metabolism-related pathways were enriched in the experimental group. CONCLUSION: This study enhanced the current understanding of the mechanisms underlying pathogenic microbiomes in PPROM-induced neonatal septicemia. The trial registry number is ChiCTR2300070666 (URL: https://www.chictr.org.cn/showproj.html?proj=195648).

16.
Bioprocess Biosyst Eng ; 46(9): 1331-1340, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37470869

RESUMEN

Chemoenzymatic epoxidation of olefin mediated by lipase is a green and environmentally friendly alternative process. However, the mass transfer barrier and lipase deactivation caused by the traditional organic-water biphasic reaction system have always been the focus of researchers' attention. To overcome these issues, we investigated the effects of reaction temperature and two important substrates (H2O2 and acyl donor) on the epoxidation reaction and interfacial mass transfer. As a result, we determined the optimal reaction conditions: a temperature of 30 °C, 30 wt-% H2O2 as the oxygen source, and 1 M lauric acid as the oxygen carrier. Additionally, by simulating the conditions of shaking flask reactions, we designed a batch reactor and added a metal mesh to effectively block the direct contact between high-concentration hydrogen peroxide and the enzyme. Under these optimal conditions, the epoxidation reaction was carried out for 5 h, and the product yield reached a maximum of 93.2%. Furthermore, after seven repetitive experiments, the lipase still maintained a relative activity of 51.2%.


Asunto(s)
Peróxido de Hidrógeno , Lipasa , Monoterpenos Bicíclicos , Alquenos
17.
Nature ; 619(7969): 293-299, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37286604

RESUMEN

Although organic-inorganic hybrid materials have played indispensable roles as mechanical1-4, optical5,6, electronic7,8 and biomedical materials9-11, isolated organic-inorganic hybrid molecules (at present limited to covalent compounds12,13) are seldom used to prepare hybrid materials, owing to the distinct behaviours of organic covalent bonds14 and inorganic ionic bonds15 in molecular construction. Here we integrate typical covalent and ionic bonds within one molecule to create an organic-inorganic hybrid molecule, which can be used for bottom-up syntheses of hybrid materials. A combination of the organic covalent thioctic acid (TA) and the inorganic ionic calcium carbonate oligomer (CCO) through an acid-base reaction provides a TA-CCO hybrid molecule with the representative molecular formula TA2Ca(CaCO3)2. Its dual reactivity involving copolymerization of the organic TA segment and inorganic CCO segment generates the respective covalent and ionic networks. The two networks are interconnected through TA-CCO complexes to form a covalent-ionic bicontinuous structure within the resulting hybrid material, poly(TA-CCO), which unifies paradoxical mechanical properties. The reversible binding of Ca2+-CO32- bonds in the ionic network and S-S bonds in the covalent network ensures material reprocessability with plastic-like mouldability while preserving thermal stability. The coexistence of ceramic-like, rubber-like and plastic-like behaviours within poly(TA-CCO) goes beyond current classifications of materials to generate an 'elastic ceramic plastic'. The bottom-up creation of organic-inorganic hybrid molecules provides a feasible pathway for the molecular engineering of hybrid materials, thereby supplementing the classical methodology used for the manufacture of organic-inorganic hybrid materials.

19.
Anal Sci ; 39(10): 1727-1739, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37344740

RESUMEN

Nanomaterials with intrinsic enzyme-like activity have gained substantial scientific attention as viable substitutes to natural biological enzymes owing to their cheap price and great stability. Numerous artificial enzyme mimics have been employed effectively in sectors such as sensing, environmental processing, and cancer treatment. In this study, novel nitrogen-doped porous carbon nanomaterials (CPs) were produced by modifying polypyrrole with magadiite using chemical oxidative polymerization and calcination methods. The obtained nitrogen-doped porous carbon nanomaterials exhibited improved peroxidase-like activity, which catalyzed the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2) to produce colorful compounds. Kinetic investigation revealed that the affinity for TMB of nitrogen-doped porous carbon peroxidase mimics was higher than that of genuine horseradish peroxidase (HRP). In addition, a sensitive assay with encouraging performance for the colorimetric detection of ascorbic acid (AA) was successfully fabricated employing nitrogen-doped porous carbon nanomaterials as peroxidase mimics. The results were satisfactory and demonstrated its potential application in antioxidant detection.


Asunto(s)
Nanoestructuras , Peroxidasa , Peroxidasa/química , Antioxidantes , Polímeros , Ácido Ascórbico , Carbono/química , Nitrógeno , Glucosa , Colorimetría/métodos , Peróxido de Hidrógeno/química , Porosidad , Pirroles , Peroxidasas , Nanoestructuras/química , Colorantes
20.
Nat Biomed Eng ; 7(5): 629-646, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36797418

RESUMEN

The monogenic nature of Huntington's disease (HD) and other neurodegenerative diseases caused by the expansion of glutamine-encoding CAG repeats makes them particularly amenable to gene therapy. Here we show the feasibility of replacing expanded CAG repeats in the mutant HTT allele with a normal CAG repeat in genetically engineered pigs mimicking the selective neurodegeneration seen in patients with HD. A single intracranial or intravenous injection of adeno-associated virus encoding for Cas9, a single-guide RNA targeting the HTT gene, and donor DNA containing the normal CAG repeat led to the depletion of mutant HTT in the animals and to substantial reductions in the dysregulated expression and neurotoxicity of mutant HTT and in neurological symptoms. Our findings support the further translational development of virally delivered Cas9-based gene therapies for the treatment of genetic neurodegenerative diseases.


Asunto(s)
Enfermedad de Huntington , Animales , Porcinos , Enfermedad de Huntington/genética , Enfermedad de Huntington/terapia , Enfermedad de Huntington/metabolismo , Expansión de Repetición de Trinucleótido , Sistemas CRISPR-Cas/genética , Ingeniería Genética
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