1,024 research outputs found
Nanotherapeutics in angiogenesis: synthesis and in vivo assessment of drug efficacy and biocompatibility in zebrafish embryos
Author name used in this publication: Wong, Wing-Tak.published_fina
Development and evaluation of pH-responsive single-walled carbon nanotube-doxorubicin complexes in cancer cells
Single-walled carbon nanotubes (SWNTs) have been identified as an efficient drug carrier. Here a controlled drug-delivery system based on SWNTs coated with doxorubicin (DOX) through hydrazone bonds was developed, because the hydrazone bond is more sensitive to tumor microenvironments than other covalent linkers. The SWNTs were firstly stabilized with polyethylene glycol (H2N-PEG-NH2). Hydrazinobenzoic acid (HBA) was then covalently attached on SWNTs via carbodiimide-activated coupling reaction to form hydrazine-modified SWNTs. The anticancer drug DOX was conjugated to the HBA segments of SWNT using hydrazine as the linker. The resulting hydrazone bonds formed between the DOX molecules and the HBA segments of SWNTs are acid cleavable, thereby providing a strong pH-responsive drug release, which may facilitate effective DOX release near the acidic tumor microenvironment and thus reduce its overall systemic toxicity. The DOX-loaded SWNTs were efficiently taken up by HepG2 tumor cells, and DOX was released intracellularly, as revealed by MTT assay and confocal microscope observations. Compared with SWNT-DOX conjugate formed by supramolecular interaction, the SWNT-HBA-DOX featured high weight loading and prolonged release of DOX, and thus improved its cytotoxicity against cancer cells. This study suggests that while SWNTs have great potential as a drug carrier, the efficient formulation strategy requires further study
Complete genome sequence of Thermaerobacter marianensis type strain (7p75a).
Thermaerobacter marianensis Takai et al. 1999 is the type species of the genus Thermaerobacter, which belongs to the Clostridiales family Incertae Sedis XVII. The species is of special interest because T. marianensis is an aerobic, thermophilic marine bacterium, originally isolated from the deepest part in the western Pacific Ocean (Mariana Trench) at the depth of 10.897m. Interestingly, the taxonomic status of the genus has not been clarified until now. The genus Thermaerobacter may represent a very deep group within the Firmicutes or potentially a novel phylum. The 2,844,696 bp long genome with its 2,375 protein-coding and 60 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project
Syntropic spin alignment at the interface between ferromagnetic and superconducting nitrides
The magnetic correlations at the superconductor/ferromagnet (S/F) interfaces
play a crucial role in realizing dissipation-less spin-based logic and memory
technologies, such as triplet-supercurrent spin-valves and "{\pi}" Josephson
junctions. Here we report the coexistence of an induced large magnetic moment
and a crypto ferromagnetic state at high-quality nitride S/F interfaces. Using
polarized neutron reflectometry and d. c. SQUID measurements, we quantitatively
determined the magnetization profile of S/F bilayer and confirmed the induced
magnetic moment in the adjacent superconductor only exists below TC.
Interestingly, the direction of the induced moment in the superconductors was
unexpectedly parallel to that in the ferromagnet, which contrasts with earlier
findings in S/F heterostructures based on metals or oxides. The
first-principles calculations verify the observed unusual interfacial spin
texture is caused by the Heisenberg direct exchange coupling through d orbital
overlapping and severe charge transfer across the interfaces. Our work
establishes an incisive experimental probe for understanding the magnetic
proximity behavior at S/F interfaces and provides a prototype epitaxial
building block for superconducting spintronics.Comment: 21 pages, 5 figures, supplementary file with 14 figure
Strain mediated phase crossover in Ruddlesden Popper nickelates
Recent progress on the signatures of pressure-induced high temperature
superconductivity in Ruddlesden Popper (RP) nickelates (Lan+1NinO3n+1) has
attracted growing interest in both theoretical calculations and experimental
efforts. The fabrication of high-quality single crystalline RP nickelate thin
films is critical for possible reducing the superconducting transition pressure
and advancing applications in microelectronics in the future. In this study, we
report the observations of an active phase transition in RP nickelate films
induced by misfit strain. We found that RP nickelate films favor the perovskite
structure (n = infinite) under tensile strains, while compressive strains
stabilize the La3Ni2O7 (n = 2) phase. The selection of distinct phases is
governed by the strain dependent formation energy and electronic configuration.
In compressively strained La3Ni2O7, we experimentally determined splitting
energy is ~0.2 eV and electrons prefer to occupy in-plane orbitals. First
principles calculations unveil a robust coupling between strain effects and the
valence state of Ni ions in RP nickelates, suggesting a dual driving force for
the inevitable phase co-existence transition in RP nickelates. Our work
underscores the sensitivity of RP nickelate formation to epitaxial strain,
presenting a significant challenge in fabricating pure-phase RP nickelate
films. Therefore, special attention to stacking defects and grain boundaries
between different RP phases is essential when discussing the pressure-induced
superconductivity in RP nickelates.Comment: 29 pages, 5 figures, one supplementary material
Traditional Chinese medicine Dingkun pill to increase fertility in women with a thin endometrium—a prospective randomized study
ObjectiveThe aim of this study is to optimize the treatment methods of infertility, which is suggested to be mainly caused by thin endometrium, using a special form of traditional Chinese medicine, the Dingkun pill (DKP), to increase the beneficial endometrial effect of conventional hormone/progestogen therapy.MethodsA total of 307 patients visiting our specialized gynecological endocrinology department because of infertility, which we suggested to be caused by thin endometrium [endometrial thickness (EMT) < 7 mm], were randomly assigned to the experimental group and the control group. The experimental group was treated with estradiol + sequential dydrogesterone + DKP (every day); the control group received hormonal treatment without the Chinese medicine. All patients were monitored in terms of follicle diameter, EMT, and endometrial type every 2 days from the 8th to the 10th day of the menstrual cycle until ovulation day during three menstrual cycles. Serum progesterone levels on 7–8 days after ovulation were measured, and the cumulative pregnancy rate during three menstrual cycles between the two groups was compared.ResultsEMT on ovulation day in the experimental group was significantly higher than that in the control group (7.88 vs. 7.15 mm; p < 0.001). The proportion of type A and type B endometrium in total was significantly higher in the experimental group than that in the control group (83.2% vs. 77.7%; p < 0.05). Progesterone levels were significantly higher in the experimental group than those in the control group (10.874 vs. 10.074 ng/mL; p < 0.001). The cumulative pregnancy rate, the main outcome of the study, was significantly higher in the experimental group than that in the control group (29.2% vs. 15.7%; p < 0.05).ConclusionDKP added to conventional estrogen/progestogen therapy can significantly improve EMT and luteal function in patients attending due to infertility. Because this regimen increased the cumulative pregnancy rate in our study, we conclude that DKP can be used to increase the so-called “thin endometrium infertility”
Ovarian tissue cryopreservation in the pediatric with rare diseases- experience from China’s first and the largest ovarian tissue cryobank
BackgroundThere is limited information about the efficacy of ovarian tissue cryopreservation (OTC) in children. In the present study, we report eight patients with rare diseases who underwent OTC in China’s first and largest ovarian tissue cryobank.ProcedureData from girls with rare diseases who underwent OTC between September 2020 and November 2022 were retrospectively analyzed. We also compared the number of cryopreserved cortex pieces, follicle number, and AMH in those with rare diseases and age-matched children with non-rare diseases who also underwent OTC in our cryobank.ResultsThe median age of the children was 5.88 ± 3.52 (range 2-13) years old. Unilateral oophorectomy was undertaken via laparoscopy in all of the children. The diseases in the 8 patients were: 4 mucopolysaccharidoses (MPS I two cases, IVA two cases), 1 Diamond-Blackfan anemia (DBA), 1 Fanconi anemia (FA), 1 hyperimmunoglobulin E syndrome (HIES), 1 Niemann-Pick disease. The number of cryopreserved cortex pieces was 17.13 ± 6.36, and the follicle count per 2 mm biopsy was 447.38 ± 524.35. No significant difference in age, the count of cryopreserved cortex pieces, follicle number per 2 mm biopsy, and AMH level was seen between the 20 children with non-rare diseases and those with rare diseases.ConclusionsThe reports help practitioners counsel girls with rare diseases about fertility preservation. The demand for OTC in pediatrics will likely grow as a standard of care
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