221 Objectives The human induced pluripotent stem cells (hiPSCs) have gained increasing interest for tissue regeneration and transplantation therapies since their discovery. However, teratoma formation after iPSCs transplantation is one of the most serious drawbacks that may limit their further clinical application. We investigated here whether the human hiPSC-derived teratomas could be detected by an integrin targeting agent 99mTc-PEG4-E[PEG4-c(RGDfK)]2 (99mTc-3PRGD2). Methods The hiPSCs were reprogrammed from neonatal human dermal fibroblasts by introducing OCT4, SOX2, C-MYC and KLF4. The successful generation of hiPSCs was verified by immunofluoresence staining, microarray and bisulfite sequencing experiments. The hiPSCs were subcutaneously injected into the right thighs of severe combined immunodeficient (SCID) mice. After about six weeks, the teratoma formation was observed, and the teratoma-bearing mice were then subjected to biodistribution and small-animal SPECT/CT imaging of 99mTc-3PRGD2, and microPET imaging of 18F-FDG. Results 99mTc-3PRGD2 showed high (2.82 ± 0.21 and 2.69 ± 0.73 %ID/g at 0.5 and 1 h p.i., respectively) and specific (teratoma uptake decreased from 2.69 ± 0.73 to 0.53 ± 0.26 %ID/g after blocking with cold 3PRGD2) uptake in teratoma tissues.18F-FDG showed low teratoma uptake, and thus failed to detect the teratomas. 99mTc-3PRGD2 showed high contrast teratoma imaging by small-animal SPECT/CT. Ex vivo immunofluorescence staining validated the integrin αvβ3 expression in the vasculature during teratoma formation. Conclusions SPECT/CT with 99mTc-3PRGD2 is a promising approach for the noninvasive monitoring of tumorigenicity after hiPSCs transplantation
Plantations in dry and semi-arid areas significantly affect the soil's ability to store carbon and maintain a stable water balance. It is yet unclear, though, how planted trees in these regions might impact the soil's carbon and water levels. As a forest ages, it is unknown how soil water and soil carbon interact with one another. In order to conduct this study, four Saxaul plantations in the Alxa Plateau were chosen, with the neighboring mobile sandy (MS) ground serving as a control. The ages of the plantations ranged from 5 to 46 years. The major topics of the study included the relationship between soil water and soil carbon, changes in the 0-300 cm soil layer's soil water content (SWC), soil organic carbon (SOC), and soil inorganic carbon (SIC) following afforestation. The findings demonstrated that, in comparison to MS, afforestation considerably increased SOC and SIC stocks. In comparison to MS, the SIC grew by 4.02 kg m
The molecules of the title compound, C7H9N5O2, are almost completely planar. All bond lengths and angles show normal values. Hydrogen bonds of the form N—H⋯O interconnect the molecules to form a three-dimensional network.
Haloxylon ammodendron is a desert shrub widely used as a windbreak and for sand fixation, and it has achieved remarkable results in China. However, in desert areas, large-scale afforestation increases soil water consumption and forms a dried soil layer (DSL), the development of which seriously threatens the sustainable development of the ecosystem. In this study, soil moisture in the 0-400 cm soil profile was measured in selected 5-, 11-, 22-, 34-, and 46-year-old plantations of Haloxylon ammodendron plantations in Alxa Legue, China, and three soil desiccation evaluation indices were calculated-the soil desiccation index (SDI), DSL thickness (DSLT), and DSL soil water content (DSL-SWC)-to analyze the change pattern of the soil water content for different stand ages. The results showed that the shallow water layer (0-200 cm) was depleted sharply in the first five years of Haloxylon ammodendron plantation growth, but no DSL developed; the inflection point of soil water content change appeared after 10 years of growth, after which the shallow soil water was depleted and the drying process of the deep soil water content was significantly faster than that in the early growth period. The deep soil layer (200-400 cm) was depleted seriously after 22 years of afforestation, the soil drying phenomenon was obvious, and the DSL developed from the 172 cm soil layer. After 46 years of afforestation, the DSL was fully developed and the DSL-SWC was only 0.034 cm3 cm-3. Priority should thus be given to the use of less water-consuming shrub species; alternatively, after 5 years of growth of Haloxylon ammodendron plantations, certain water control measures should be taken to maintain the soil water balance.
As a vital conservation area for water sources in the Yellow River Basin, understanding the spatial-temporal dynamics of vegetation coverage is crucial, along with the factors that affect it, to ensure ecological preservation and sustainable development of the Yellow River Source Region (YRSR). In this paper, we utilized Landsat surface reflectance data from 2000 to 2020 using de-clouding and masking methods implementing the Google Earth Engine (GEE) cloud platform. We investigated spatial-temporal changes in vegetation coverage by combining the maximum value composite (MVC), the dimidiate pixel model (DPM), the Theil–Sen median slope, and the Mann–Kendall test. The influencing factors on vegetation coverage were quantitatively analyzed using a geographic detector, and future tendencies in vegetation coverage were predicted utilizing the Future Land Use Simulation (FLUS) model. The outcomes suggested the following: (1) On the temporal scale, vegetation coverage exhibited a general upward trend between 2000 and 2020, with the YRSR showing a yearly growth rate of 0.23% (p < 0.001). In comparison to 2000, the area designated as having extremely high vegetation coverage increased by 19.3% in 2020. (2) Spatially, the central and southeast regions have higher values of vegetation coverage, whereas the northwest has lower values. In the study area, 75.5% of the region demonstrated a significant improvement trend, primarily in Xinghai County, Zeku County, and Dari County in the south and the northern portion of the YRSR; conversely, a notable tendency of degradation was identified in 11.8% of the area, mostly in the southeastern areas of Qumalai County, Chenduo County, Shiqu County, and scattered areas in the southeastern region. (3) With an explanatory power of exceeding 45%, the three influencing factors that had the biggest effects on vegetation coverage were mean annual temperature, elevation, and mean annual precipitation. Mean annual precipitation has been shown to have a major impact on vegetation covering; the interconnections involving these factors have increased the explanatory power of vegetation coverage’s regional distribution. (4) Predictions for 2030 show that the vegetation coverage is trending upward in the YRSR, with a notable recovery trend in the northwestern region. This study supplies a theoretical foundation to formulate strategies to promote sustainable development and ecological environmental preservation in the YRSR.
Two complexes [MnL 2 (H 2 O) 2 ]·2ClO 4 (complex 1) and [CuL(H 2 O) 3 ]·2NO 3 (complex 2) (where L = 3,5‐bis(1‐imidazoly) pyridine) were designed and synthesized. The structures of the complexes were characterized by X‐ray crystallography, elemental analyses, and infrared spectrum. The interaction capacity of the complexes with calf thymus DNA has been investigated by UV and fluorescence spectroscopy. Gel electrophoresis assay demonstrated the ability of the complexes to cleave the pBR322 plasmid DNA. Efficient binding properties of DNA were established by UV–vis, fluorescence, and gel electrophoresis. The intrinsic binding constants ( K b ) were calculated to be 0.1524, 0.1041 for complexes 1–2, respectively. The cytotoxic activity of the two complexes exhibited a higher cytotoxicity against HeLa cell lines and lower cytotoxicity toward the normal cell lines. Flow cytometry demonstrated the cancer cell inhibitory rate of two complexes. Furthermore, computer‐aided molecular docking studies were performed to visualize the binding mode of the drug candidate at the molecular level. Interestingly, complex 1 exhibited a significant cancer cell inhibitory rate than cisplatin and other complexes.
A series of novel cytotoxic compounds, [Mn(cpt) 2 ], [Zn(tpt)(H 2 O) 2 ]⋅DMA⋅2(H 2 O) and [Cu(tpt)]⋅DMA (cpt = 4′‐(4‐carboxyphenyl)‐2,2′:6′,2″‐terpyridine, tpt = 4‐(2,4,6‐tricarboxylphenyl)‐2,2′:6′,2″‐terpyridine, DMA = (CH 3 ) 2 NH), were isolated and characterized. The structures of these complexes were characterized using single‐crystal X‐ray diffraction. The mode and extent of binding between fish sperm DNA and the complexes were investigated using fluorescence spectroscopy and molecular docking. These results indicate the ability of the complexes to bind to DNA with different binding affinities. The binding of the Zn(II) complex with DNA is stronger than that of the corresponding Cu(II) analogue, which is expected due to the z* effect and geometry. The ability of these complexes to cleave pBR322 plasmid DNA was demonstrated using gel electrophoresis assay, showing that the complexes have effective DNA cleavage activity. In addition, the cytotoxic effects of these complexes were examined on HeLa cells (human cervix epithelia carcinoma cells) in vitro . The three complexes exhibit different cytotoxic effects and decent cancer cell inhibitory rate. This means that the structures and type of metal have a great influence on the activity of these novel complexes.
In the title compound, [Zn(C14H8Br2N2O3)(C5H5N)2], the ZnII ion is coordinated by one N and two O atoms from a Schiff base ligand and by the N atoms of two pyridine molecules to form a distorted trigonal–bipyramidal geometry.
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