Isolation, characteristics, and poly(butylene adipate-co-terephthalate) (PBAT) degradation mechanism of a marine bacteria Roseibium aggregatum ZY-1.

Marine microorganisms have been reported to degrade microplastics. However, the degradation mechanisms are still poorly understood. In this study, a bacterium Roseibium aggregatum ZY-1 was isolated from seawater, which can degrade poly(butylene adipate-co-terephthalate) (PBAT). The PBAT-PLA(polylactic acid, PLA) films, before and after degradation, were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectrometer (FTIR), the weight loss rate and water contact angle were measured. The results indicate that ZY-1 colonized on PBAT-PLA film, changed the functional groups and decreased water contact angle of PBAT-PLA film. Moreover, liquid chromatography mass spectrometry (LC-MS) analysis reveales that PBAT was degraded into its oligomers (TB, BTB) and monomers (T, A) during 10 days, and adipic acid (A) could be used as a sole carbon source. The whole genome sequencing analyses illustrate the mechanisms and enzymes such as PETase, carboxylesterases, arylesterase (PpEst) and genes like pobA, pcaBCDFGHIJKT, dcaAEIJK, paaGHJ involved in PBAT degradation. Therefore, the R. aggregatum ZY-1 will be a promising candidate of PBAT degradation.

The cryptic step in the biogeochemical tellurium (Te) cycle: Indirect elementary Te oxidation mediated by manganese-oxidizing bacteria Bacillus sp. FF-1.

Tellurium (Te) is a rare element within the chalcogen group, and its biogeochemical cycle has been studied extensively. Tellurite (Te(IV)) is the most soluble Te species and is highly toxic to organisms. Chemical or biological Te(IV) reduction to elemental tellurium (Te0) is generally considered an effective detoxification route for Te(IV)-containing wastewater. This study unveils a previously unnoticed Te0 oxidation process mediated by the manganese-oxidizing bacterium Bacillus sp. FF-1. This bacterium, which exhibits both Mn(II)-oxidizing and Te(IV)-reducing abilities, can produce manganese oxides (BioMnOx) and Te0 (BioTe0) when exposed to Mn(II) and Te(IV), respectively. When 5 mM Mn(II) was added after incubating 0.1 mM or 1 mM Te(IV) with strain FF-1 for 16 h, BioTe0 was certainly re-oxidized to Te(IV) by BioMnOx. Chemogenic and exogenous biogenic Te0 can also be oxidized by BioMnOx, although at different rates. This study highlights a new transformation process of tellurium species mediated by manganese-oxidizing bacteria, revealing that the environmental fate and ecological risks of Te0 need to be re-evaluated.

Competitive Mn(II) removal occurs in Lysinibacillus sp. MHQ-1 through microbially-induced carbonate precipitation (MICP) and indirect Mn(II) oxidation.

Biological Mn(II) removal usually involves adsorption and precipitation of Mn(II) in the form of various minerals. Manganese oxides (MnOx) formation through the activity of Mn(II) oxidation bacteria (MnOB) contributes to the majority of Mn(II) removal. However, whether other bacterial-mediated pathway could couple or competitive with Mn(II) oxidation during Mn(II) removal is scarcely reported. In this study, we reported a competitive Mn(II) removal occurred in nutrient-rich condition during the indirect Mn(II) oxidation of Lysinibacillus sp. MHQ-1, i.e., microbially-induced carbonate precipitation (MICP). In the presence of 1 mM Mn(II), 39.4% of free Mn(II) converted to MnCO3(s) quickly within 100 h, and then 11.6% of initial Mn(II) slowly oxidized to MnOx within 442 h. The urease activity assay and the genome sequencing confirmed the existence of urease and the absence of Mn(II)-oxidizing enzymes in the genome of strain MHQ-1. The urease catalyzed the formation of carbonate ion that reacts with Mn(II) and the formed ammonia raises the pH to initiate indirect Mn(II) oxidation. Genome survey suggests the urease widely exists in various Mn(II)-oxidizing bacteria (MnOB), emphasizing the importance to reconsider the composition, stability and environmental effects of biological Mn(II) removal products in nutrient-rich environment.

Evidence-based summary for the safety of multiple medication in elderly patients with ischemic stroke.

Background: To retrieve, analyze, and summarize the relevant evidence of home-based medications use for stroke patients, so as to provide evidence for safe home-based medication of elderly patients with ischemic stroke. Methods: We performed a search in the databases of British Medical Journal (BMJ) Best Practice, UpToDate, Joanna Briggs Institute (JBI) Evidence-based Health Care Center Library, Cochrane Library, PubMed, China National Knowledge Infrastructure (CNKI), Wanfang Knowledge Data Service Platform, and others, according to the evidence pyramid model. We retrieved all evidence on the safety of home-based multiple medications use in elderly patients with ischemic stroke, including clinical decision-making, expert consensus, guidelines, systematic reviews, and summary of evidence. The search time limit was from the establishment of the database to March 2021. The literature evaluation standard and evidence grading system of JBI Evidence-based Health Care Center were used to evaluate the quality of the literature, and to classify the extracted evidence. Results: A total of 17 articles were included in this study, comprising 2 guidelines, 11 systematic reviews, 3 evidence summaries, and 1 expert consensus. This article summarizes the 7 best evidences from 5 aspects: drug dispensing, drug identification, medication time, prescription simplification, and self-management plan. Conclusions: The evidence of home-based multiple medication use in elderly patients with ischemic stroke provides an evidence-based reference for ensuring the safety of medications for patients, and guides elderly patients with ischemic stroke and their caregivers by applying the best available evidence.

[Comparative study on effect of electroacupuncture at lower he-sea point of stomach and he-sea matching front-mu points for gastroparesis].

OBJECTIVE: To explore the efficacy difference of electroacupuncture at lower he-sea point and he-sea matching front-mu points for the treatment of gastroparesis. METHODS: A total of 63 patients with gastroparesis were randomly divided into a lower he point group (group A, 32 cases, 2 cases dropped off) and a he matching mu points group (group B, 31 cases, 1 case dropped off). The group A was treated with electroacupuncture at Zusanli (ST 36), and the group B was treated with electroacupuncture at Zusanli (ST 36) and Zhongwan (CV 12). Both groups were treated with continuous wave (2 Hz in frequency) for 30 min, once a day, 5 times a week for 3 weeks. The gastroparesis cardinal symptom index (GCSI) score, gastric half-emptying time (T1/2) and the 180 min gastric residual rate of the two groups before and after treatment were observed, and the clinical effective rate was compared. RESULTS: After treatment, the total GCSI scores, T1/2 and the 180 min gastric residual rates in both groups were lower than those before treatment (P<0.01), and the 180 min gastric residual rate and T1/2 in the group A were lower than those in the group B (P<0.05). The total effective rate was 93.3% (28/30) in the group A, which was superior to 70.0% (21/30) in the group B (P<0.05). CONCLUSION: Electroacupuncture at lower he-sea point and he-sea matching front-mu points can both be used to treat gastroparesis, but electroacupuncture at Zusanli (ST 36) has a better effect. The acupoints of Zusanli (ST 36) and Zhongwan (CV 12) may have antagonistic effects.

Two new Cu(II)-based coordination polymers: inhibitory activity on prostate cancer by reducing EGF-R expression and HIPPO signaling pathway activation.

Under solvothermal conditions, two new coordination polymers (CPs), namely {[Cu(HL)]·2CH3CN}n (1) and {[Cu(HL)(bimb)]·4H2O}n (2) (H3L = tris(p-carboxyphenyl)phosphane oxide, bimb = 1,4-bis(imidazol-1-ylmethyl)benzene) were prepared. Their treatment activity on the human prostate cancer was evaluated through series of biological experiments. Firstly, the human prostate cancer cells proliferation was determined with Cell Counting Kit-8 (CCK-8) detection kit. The influence of compounds 1 and 2 on the cancer cells migration and invasion ability was measured with trans-well assay. Next, the important role of the EGF-R human prostate cancer cells was determined with western blotting. In the end, the activation of the HIPPO signaling pathway was detected with real-time reverse transcription polymerase chain reaction (RT-PCR).

Cyclometalated Platinum(II) Complexes of 1,3-Bis(1-n-butylpyrazol-3-yl)benzenes: Synthesis, Characterization, Electrochemical, Photophysical, and Gelation Behavior Studies.

A new series of cyclometalated platinum(II) complexes of N^C^N ligands, where N^C^N = 1,3-bis(1-n-alkylpyrazol-3-yl)benzene (bpzb), namely, [Pt(bpzb)Cl] (1 and 2) and [Pt(bpzb)(C≡C-R)] (3-10) (R = C6H5, C6H4-OCH3-p, C6H4-NO2-p, C6H4-NH2-p, 4-cholesteryl phenyl carbamate, and cholesteryl methylcarbamate) were synthesized and characterized. Their electrochemical and photophysical properties were investigated. Two of the platinum(II) complexes were also structurally characterized by X-ray crystallography, and short intermolecular C-H···Pt contacts were observed. Vibronic-structured emission bands originating from triplet IL (3IL) excited states of the bpzb ligands with mixing of some 3MLCT [dπ(Pt)→π*(bpzb)] character were observed in solution state. Interestingly, complex 5 shows a low-energy emission that is derived from the involvement of the p-nitrophenylethynyl ligand. Complex 9 with hydrophobic cholesteryl 4-ethynylphenyl carbamate ligand was found to form stable metallogels in several organic solvents, which are responsive to mechanical sonication and thermal stimuli and show circular dichroism activity.

A "strongly" self-catenated metal-organic framework with the highest topological density among 3,4-coordinated nets.

A new type of 3D "strongly" self-catenated metal-organic framework (SDU-9) has been constructed from [Cu2(COO)4] paddlewheel secondary building units and a tripodal carboxylate linker. SDU-9 ([Cu6(H2O)6L4]·24H2O, where [H3L = 4,4',4"-(hydroxysilanetriyl)tris(triphenyl-4-carboxylic acid), represents a rare example of a highly symmetrical coordination network and extremely tight self-catenation. To the best of our knowledge, SDU-9 has the highest topological density among all known 3,4-coordinated nets.

Synergistic anticancer activity of 5-aminolevulinic acid photodynamic therapy in combination with low-dose cisplatin on Hela cells.

OBJECTIVE: Photodynamic therapy (PDT ) is a promising modality for the treatment of various tumors. In order to assist in optimizing treatment, we applied 5-ALA/PDT in combination with low-dose cisplatin to evaluate cytotoxicity in Hela cells. METHODS: Antiproliferative effects of 5-ALA/PDT and cisplatin, alone and in combination, were assessed using MTT assay. To examine levels of apoptosis, Hela cells treated with 5-ALA/PDT, and combination treatment were assessed with Annexin-V/PI by flow cytometry. To investigate the molecular mechanisms underlying alterations in cell proliferation and apoptosis, Western blot analysis was conducted to determine the expression of p53, p21, Bax and Bcl-2 proteins. RESULTS: MTT assays indicated that combination treatment obviously decreased the viability of Hela cells compared to individual drug treatment. In addition, it was confirmed that exposure of Hela cells to 5-ALA/PDT in combination with low-dose cisplatin resulted in more apoptosis in vitro. Synergistic anticancer activity was related to upregulation p53 expression and alteration in expression of p21, Bcl-2 and Bax. CONCLUSION: Our findings suggest that administration of 5-ALA/PDT in combination with the low-dose cisplatin may be an effective and feasible therapy for cervical cancer.

Control over interpenetration in lanthanide-organic frameworks: synthetic strategy and gas-adsorption properties.

Two isostructural lanthanide-organic frameworks (1 and 2) with 2-fold interpenetrating nets have been synthesized based on 1,4-benzenedicarboxylic acid (H(2)BDC). By application of an organic ligand with hindrance groups and a terminal chelating ligand to replace BDC and coordinated solvates, interpenetration has been effectively controlled. The gas-sorption properties of the noninterpenetrating net have been studied.

A surface-charge study on cellular-uptake behavior of F3-peptide-conjugated iron oxide nanoparticles.

Surface-charge measurements of mammalian cells in terms of Zeta potential are demonstrated as a useful biological characteristic in identifying cellular interactions with specific nanomaterials. A theoretical model of the changes in Zeta potential of cells after incubation with nanoparticles is established to predict the possible patterns of Zeta-potential change to reveal the binding and internalization effects. The experimental results show a distinct pattern of Zeta-potential change that allows the discrimination of human normal breast epithelial cells (MCF-10A) from human cancer breast epithelial cells (MCF-7) when the cells are incubated with dextran coated iron oxide nanoparticles that contain tumor-homing F3 peptides, where the tumor-homing F3 peptide specifically bound to nucleolin receptors that are overexpressed in cancer breast cells.