Effect of phenol formaldehyde-associated microplastics on soil microbial community, assembly, and functioning.

Increasing investigations explore the effects of plastic pollutants on bacterial communities, diversity, and functioning in various ecosystems. However, the impact of microplastics (MPs) on the eukaryotic community, microbial assemblages, and interactions is still limited. Here, we investigated bacterial and micro-eukaryotic communities and functioning in soils with different concentrations of phenol formaldehyde-associated MPs (PF-MPs), and revealed the factors, such as soil properties, microbial community assembly, and interactions between microbes, influencing them. Our results showed that a high concentration (1%) of PF-MPs decreased the microbial interactions and the contribution of deterministic processes to the community assembly of microbes, and consequently changed the communities of bacteria, but not eukaryotes. A significant and negative relationship was determined between N2O emission rate and functional genes related to nitrification, indicating that the competitive interactions between functional microbes would affect the nitrogen cycling of soil ecosystem. We further found that vegetable biomass weakly decreased in treatments with a higher concentration of PF-MPs and positively related to the diversity of micro-eukaryotic communities and functional diversity of bacterial communities. These results suggest that a high concentration of the PF-MPs would influence crop growth by changing microbial communities, interactions, and eukaryotic and functional diversity. Our findings provide important evidence for agriculture management of phenol formaldehyde and suggest that we must consider their threats to microbial community compositions, diversity, and assemblage in soils due to the accumulation of PF-MPs widely used in the field.

Watershed urbanization enhances the enrichment of pathogenic bacteria and antibiotic resistance genes on microplastics in the water environment.

Microplastics (MPs) serve as vectors for microorganisms and antibiotic resistance genes (ARGs) and contribute to the spread of pathogenic bacteria and ARGs across various environments. Patterns of microbial communities and ARGs in the biofilm on the surface of MPs, also termed as plastisphere, have become an issue of global concern. Although antibiotic resistome in the plastisphere has been detected, how watershed urbanization affects patterns of potential pathogens and ARGs in the microplastic biofilms is still unclear. Here, we compared the bacterial communities, the interaction between bacterial taxa, pathogenic bacteria, and ARGs between the plastisphere and their surrounding water, and revealed the extensive influence of urbanization on them. Our results showed that bacterial communities and interactions in the plastisphere differed from those in their surrounding water. Microplastics selectively enriched Bacteroidetes from water. In non-urbanized area, the abundance of Oxyphotobacteria was significantly (p < 0.05) higher in plastisphere than that in water, while α-Proteobacteria was significantly (p < 0.05) higher in plastisphere than those in water of urbanized area. Pathogenic bacteria, ARGs, and mobile genetic elements (MGEs) were significantly (p < 0.05) higher in the urbanized area than those in non-urbanized area. MPs selectively enriched ARG-carrying potential pathogens, i.e., Klebsiella pneumoniae and Enterobacter cloacae, and exhibited a distinct effect on the relative abundance of ARG and pathogens in water with different urbanization levels. We further found ARGs were significantly correlated to MGEs and pathogenic bacteria. These results suggested that MPs would promote the dissemination of ARGs among microbes including pathogenic bacteria, and urbanization would affect the impact of MPs on microbes, pathogens, and ARGs in water. A high level of urbanization could enhance the enrichment of pathogens and ARGs by MPs in aquatic systems and increase microbial risk in aquatic environments. Our findings highlighted the necessity of controlling the spread of ARGs among pathogens and the usage of plastic products in ecosystems of urban areas.

Long-acting PEGylated growth hormone in children with idiopathic short stature.

Objective: To evaluate the safety and efficacy of weekly PEGylated-recombinant human growth hormone (PEG-rhGH) in children with idiopathic short stature (ISS) in China. Design and methods: This was a multicenter, phase II study in which all subjects were randomized 1:1:1 to weekly s.c. injections of PEG-rhGH 0.1 (low-dose (LD) group) or 0.2 mg/kg/week (high-dose (HD) group) or control for 52 weeks. The primary end point was change (Δ) in height s.d. score (HT-SDS) from baseline to week 52. Secondary end points were height velocity (HV), bone maturity, insulin-like growth factor-1 (IGF-1) SDS, and IGF-1/insulin-like growth factor-binding protein-3 (IGFBP-3) molar ratio. Results: A total of 360 children with ISS were recruited in the study (n = 120 in each group). At week 52, ΔHT-SDS was 0.56 ± 0.26, 0.98 ± 0.35, and 0.20 ± 0.26 in the LD, HD, and control groups, respectively (within-group P < 0.0001; intergroup P < 0.0001). Statistically significant values of ΔHV, IGF-1, IGF-1/IGFBP-3 ratio, and IGF-1 SDS at week 52 from baseline were observed in both treatment groups (P < 0.0001). There were clear dose-dependent responses for all auxological variables. PEG-rhGH was well tolerated throughout the treatment period with treatment-emergent adverse events (TEAEs) reported in 86.5%, 84.6%, and 91.3% of children in the HD, LD, and control groups, respectively. The incidence of TEAEs was similar in all treatment groups despite the difference in doses. A total of 27 (8.7%) children experienced drug-related TEAEs. Conclusion: Fifty-two-week treatment with PEG-rhGH 0.1 or 0.2 mg/kg/week achieved significant improvement in HT-SDS and other growth-related variables, including HV, IGF-1 SDS, and IGF-1/IGFBP-3 ratio, in a dose-dependent manner. Both doses were well tolerated with similar safety profiles.

Characterization and cytotoxicity studies of DPPC:M(2+) novel delivery system for cisplatin thermosensitivity liposome with improving loading efficiency.

A novel, metal ion-assisted drug-loading model, in which the metal ion was used to modify the microstructure of DPPC bilayers, has been developed to improve the drug-loading efficiency of cisplatin thermosensitivity liposomes. The reactions of dipalmitoyl phosphatidylcholine (DPPC) with diverse metal ions (Zn(2+), Cu(2+), Mn(2+) and Mg(2+)) yield four typical liposomes, which have been characterized by FT-IR, Raman and fluorescence techniques; the mechanism for higher drug encapsulation efficiency has also been investigated. In these prepared liposomes, the conformation of DPPC is changed due to the electrostatic interaction between the metal ions and phospholipid acyl group, leading to a closer arrangement of the lipid hydrocarbon chains and higher Tm of DPPC. As a result, the encapsulation efficiency of metal ion-assisted loading liposome is significantly higher than that of metal ion-free state. While for the release time, all four metal ion-assisted liposomes could be released within 10min at 42±0.5°C, which approach to the phase transition temperature, indicating that the introduction of metal ions into the DPPC bilayer membranes has no influence on the thermosensitivity of the liposome. Furthermore, the higher cytotoxicity of metal ion-bounded liposomes than that of free cisplatin solution suggests that high encapsulation efficiency can cause cytotoxicity increase. Hence, this work highlighted that metal ion-assisted loading model increased the encapsulation efficiency and cell cytotoxicity of cisplatin in thermosensitive liposomes with no obvious effects on sustained and temperature-dependent drug release.

Reactivity of 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole, structures and magnetic properties of polynuclear and polymeric Mn(II), Cu(II) and Cd(II) complexes.

Five new complexes were obtained from solution or hydrothermal reactions of M(OAc)(2) (M = Mn, Cu and Cd) or CuCl(2) with 4-amino-3,5-bis(pyridin-2-yl)-1,2,4-triazole (abpt) and NaN(3) or 1,3,5-benzenetricarboxylic acid (btcH(3)) in different molar ratios. Structural analysis reveals that Cd(abpt) units in [Cd(abpt)(mu(1,1)-N(3))(2)](n) (1) are bridged by double mu(1,1) end-on (EO) azides into 1D zigzag coordination chains. Similar structural motifs, i.e. the chelation of abpt to the metal center and the double bridges of EO azides, are found in [Mn(4)(abpt)(4)(mu(1,1)-N(3))(8)(H(2)O)(2)] (2). The terminal aqua molecules and the monodentate N(3)(-) groups lead to the formation of a tetranuclear complex rather than a polymeric compound. The abpt underwent deamination in the presence of copper ions during the process of coordination and became 3,5-bis(pyridin-2-yl)-1,2,4-triazolate (bpt-H) in 3-5. [Cu(4)(bpt-H)(4)(N(3))(4)].4.5H(2)O (3) is a neutral tetranuclear grid-like complex, in which the azides act as monodentate ligands. A similar [Cu(4)(bpt-H)(4)](4+) grid-like unit was found in [Cu(4)(bpt-H)(4)(mu-btcH)Cl(2)].2H(2)O (4) and a pair of symmetry-related copper atoms are bridged by the mu-btcH(2)(-) coligand in a butterfly-shaped structure. In [Cu(2)(bpt-H)(mu(6)-btc)(H(2)O)](n) (5), the tetranuclear {Cu(4)(mu-bpt-H)(2)(mu(3)-carboxylate)(2)}(4+) units are bridged by mu(6)-btc(3-) ligands in a 2D step-like layer structure. Temperature-dependent magnetic susceptibility measurements reveal that the double mu(1,1)-N(3)(-) bridges in 2 transmit the ferromagnetic interactions between Mn(2+) centers (J(1) = J(2) = +3.09(4) cm(-1), g(Mn(II)) = 2.02(1)), and the mu-(bpt-H)(-) bridges transmit moderate antiferromagnetic interactions in both 3 (J = -12.78(13) cm(-1)) and 4 (J(1) = -14.96(11) cm(-1)). In 4 the antiferromagnetic coupling via the mu-btcH(2-) bridge was found as the second coupling pathway (J(2) = -9.48(7) cm(-1)). The coexistence of ferromagnetic and antiferromagnetic coupling between four Cu(2+) centers occurs in 5 (J(1) = -0.88(3) cm(-1) and J(2) = +5.01(2) cm(-1)). The magneto-structural relationship for tetranuclear copper pyrazolate/triazolate compounds has been discussed.