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Chemical Science Apr 2023The growth of porous aromatic frameworks (PAFs) on the surface of polymer brushes is reported for the first time. In contrast to PAFs formed in solution, polymer brushes...
The growth of porous aromatic frameworks (PAFs) on the surface of polymer brushes is reported for the first time. In contrast to PAFs formed in solution, polymer brushes provide a confined environment for PAF growth, resulting in nanosized and homogeneous spherical PAFs formed amongst the polymer brushes. 4-Bromobenzene functionalities from the polymer brushes are utilized to induce PAF growth by a Yamamoto-type Ullman coupling reaction. The size of PAFs can be tailored from 30 nm to 500 nm by subtly changing the structural parameters: reaction time, grafting density, and concentration of 4-bromobenzene on the surface. The established strategy is not only applicable to the preparation of PAF-1, but can also be extended to the controlled preparation of PAF-5. In addition, free-standing and flexible PS/PAF-1 hybrid membranes are obtained dissolving the oxidized layer between the polymer layer and the silicon substrate, which can be transferred to any flat substrate. The obtained PS/PAF-1 membrane is proven to show high efficiency in removing dye from water and is promising for eliminating other foulants, such as microorganisms and trace organics.
PubMed: 37035702
DOI: 10.1039/d2sc06930j -
Ecotoxicology and Environmental Safety Nov 2022Decabromodiphenyl ethane (DBDPE) is a typical flame retardant found in various electrical and textile items. DBDPE is abundantly available in the surrounding environment...
Decabromodiphenyl ethane (DBDPE) is a typical flame retardant found in various electrical and textile items. DBDPE is abundantly available in the surrounding environment and wild animals based on its persistence and bioaccumulation. DBDPE has been shown to cause apoptosis in rat spermatogenic cells, resulting in reproductive toxicity. However, the toxicity of DBDPE on the male reproductive system and the potential mechanisms are still unclear. This study evaluated the effect of DBDPE on the reproductive system in male SD rats and demonstrated the potential mechanisms of reproductive toxicity. DBDPE (0, 5, 50, and 500 mg/kg/day) was administered via gavage to male SD rats for 28 days. DBDPE caused histopathological changes in the testis, reduced sperm quantity and motility, and raised the malformation rate in rats, according to the findings. Furthermore, it caused DNA damage to rat testicular cells. It inhibited the expressions of spermatogenesis-and oogenesis-specific helix-loop-helix transcription factor 1 (Sohlh1), piwi-like RNA-mediated gene silencing 2 (MILI), cyclin-dependent kinase 2 (CDK2), and CyclinA, resulting in meiotic failure, as well as the expressions of synaptonemal complex proteins 1 and 3 (SYCP1 and SYCP3), leading to chromosomal association disorder in meiosis and spermatocyte cycle arrest. Moreover, DBDPE induced glycolipid metabolism disorder and activated mitochondria-mediated apoptosis pathways in the testes of SD rats. The quantity and quality of sperm might be declining due to these factors. Our findings offer further evidence of the harmful impact of DBDPE on the male reproductive system.
Topics: Male; Rats; Animals; Rats, Sprague-Dawley; Semen; Bromobenzenes; Flame Retardants; Glycolipids
PubMed: 36228355
DOI: 10.1016/j.ecoenv.2022.114165 -
Acta Crystallographica. Section E,... 2013In the title compound, C15H11BrN4O2S, the tetra-zole ring makes dihedral angles of 45.97 (10) and 75.41 (1)°, respectively, with the benzoyl and bromo-benzene rings...
In the title compound, C15H11BrN4O2S, the tetra-zole ring makes dihedral angles of 45.97 (10) and 75.41 (1)°, respectively, with the benzoyl and bromo-benzene rings while the dihedral angle between the benzene rings is 73.77 (1)°. In the crystal, mol-ecules are linked through O-H⋯ N and C-H⋯ O hydrogen bonds, giving infinite chains in both the [110] and [1-10] directions. These chains are further connected by C-Br⋯π and C-O⋯π inter-actions and also by π-π stacking between tetra-zole rings [centroid-centroid distance = 3.312 (1) Å], generating a three-dimensional network.
PubMed: 24046647
DOI: 10.1107/S1600536813014840 -
Acta Crystallographica. Section E,... Sep 2009In the title compound, C(16)H(11)BrO(2), the isocoumarin ring system is planar (r.m.s. deviation = 0.015 Å) and subtends a dihedral angle of 88.90 (2)° with the...
In the title compound, C(16)H(11)BrO(2), the isocoumarin ring system is planar (r.m.s. deviation = 0.015 Å) and subtends a dihedral angle of 88.90 (2)° with the bromo-benzene ring. In the crystal, mol-ecules are linked, forming a three-dimensional packing pattern involving C-H⋯O inter-actions, Br⋯O contacts [3.4734 (10) Å] and π-π stacking inter-actions with centroid-centroid distances ranging from 3.667 (2) to 3.765 (2) Å.
PubMed: 21577958
DOI: 10.1107/S1600536809037246 -
Acta Crystallographica. Section E,... Mar 2010In the title compound, C(7)H(7)BrN(2)S, the thio-urea unit is almost perpendicular to the bromo-benzene fragment, making a dihedral angle of 80.82 (16)°. The crystal...
In the title compound, C(7)H(7)BrN(2)S, the thio-urea unit is almost perpendicular to the bromo-benzene fragment, making a dihedral angle of 80.82 (16)°. The crystal structure is stabilized by N-H⋯S inter-molecular hydrogen bonds, which form linear chains along the ab diagonal.
PubMed: 21580628
DOI: 10.1107/S1600536810008305 -
Acta Crystallographica. Section E,... Jun 2009In the title compound, C(55)H(69)BrO(4), the calixarene mol-ecule displays a 'partial cone' conformation bearing the lateral substituent in a sterically favorable...
In the title compound, C(55)H(69)BrO(4), the calixarene mol-ecule displays a 'partial cone' conformation bearing the lateral substituent in a sterically favorable equatorial arrangement between two syn-orientated arene units. The crystal packing is stabilized by weak C-H⋯π contacts, involving one tert-butyl group, and π-stacking inter-actions of the lateral bromo-benzene units [centroid-centroid distance = 3.706 (1) Å].
PubMed: 21582956
DOI: 10.1107/S1600536809023137 -
Chemosphere Sep 2020This critical review summarizes the occurrence of 63 novel brominated flame retardants (NBFRs) in indoor air, dust, consumer goods and food. It includes their EU... (Review)
Review
This critical review summarizes the occurrence of 63 novel brominated flame retardants (NBFRs) in indoor air, dust, consumer goods and food. It includes their EU registration and (potential) risks. The increasing application of NBFRs calls for more research on their occurrence, environmental fate and toxicity. This review reports which NBFRs are actually being studied, which are detected and which are of most concern. It also connects data from the European Chemical Association on NBFRs with other scientific information. Large knowledge gaps emerged for 28 (out of 63) NBFRs, which were not included in any monitoring programs or other studies. This also indicates the need for optimized analytical methods including all NBFRs. Further research on indoor environments, emission sources and potential leaching is also necessary. High concentrations of 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (EH-TBB), bis(2-ethylhexyl)tetrabromophthalate (BEH-TEBP), decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) were often reported. The detection of hexabromobenzene (HBB), pentabromotoluene (PBT), 1,4-dimethyltetrabromobenzene (TBX), 4-(1,2-dibromoethyl)-1,2-dibromocyclohexane (DBE-DBCH) and tetrabromobisphenol A bis(2,3-dibromopropyl) ether (TBBPA-BDBPE) also raises concern.
Topics: Air Pollution, Indoor; Bromobenzenes; Dust; Environmental Monitoring; Flame Retardants; Halogenated Diphenyl Ethers; Halogenation; Polybrominated Biphenyls
PubMed: 32417508
DOI: 10.1016/j.chemosphere.2020.126816 -
The Journal of Toxicological Sciences 2017The aim of the present study is to investigate whether or not bromobenzene (BB) toxicity varies with circadian periodicity. Seven-week-old male ICR mice were injected...
The aim of the present study is to investigate whether or not bromobenzene (BB) toxicity varies with circadian periodicity. Seven-week-old male ICR mice were injected with 900 mg/kg (5.73 mmol/kg) BB intraperitoneally at 4 different time points of a day (zeitgeber time [ZT]: ZT0, ZT6, ZT12, and ZT18). Mortality was then monitored for 7 days after injection. Interestingly, mice were sensitive to BB acute toxicity at ZT6 while tolerant at ZT18. Moreover, in mice that were given a non-lethal dose of BB (540 mg (3.44 mmol)/kg), levels of alanine aminotransferase and aspartate aminotransferase, used as markers of hepatic injury, markedly increased in response to injection at ZT6, but did not increase significantly in response to injection at ZT18. In contrast, the markers of renal injury (creatinine and blood urea nitrogen), showed no significant difference in response to the two injection times. To further investigate this extreme circadian variation, we examined hepatic and renal lipid peroxidation levels, and conducted histopathological studies. Similar to our observation with alanine aminotransferase and creatinine, hepatic lipid peroxidation and histopathological changes were more pronounced than renal changes, and showed circadian variation. Our present investigation demonstrated that BB-induced mortality had clear circadian variation, and suggested that hepatic injury was one of the important factors for determination of this variation.
Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Blood Urea Nitrogen; Bromobenzenes; Chemical and Drug Induced Liver Injury; Circadian Rhythm; Creatinine; Kidney; Liver; Male; Malondialdehyde; Mice, Inbred ICR; Solvents
PubMed: 28321051
DOI: 10.2131/jts.42.251 -
Acta Crystallographica. Section E,... Nov 2008In the title compound, C(16)H(11)BrO(3), the mol-ecules adopt an E configuration with respect to the C=C double bond of the propenone unit. The 13 non-H atoms of the...
In the title compound, C(16)H(11)BrO(3), the mol-ecules adopt an E configuration with respect to the C=C double bond of the propenone unit. The 13 non-H atoms of the benzodioxole and propenone units are approximately coplanar (r.m.s. deviation = 0.027 Å) and the bromo-benzene ring plane forms a dihedral angle of 10.8 (1)° to this plane. The structure is layered, with the mol-ecules forming a herring-bone arrangement within each layer.
PubMed: 21581358
DOI: 10.1107/S1600536808037446 -
Toxicology Reports 2016As legacy toxicogenomics databases have become available, improved data mining approaches are now key to extracting and visualizing subtle relationships between...
As legacy toxicogenomics databases have become available, improved data mining approaches are now key to extracting and visualizing subtle relationships between toxicants and gene expression. In the present study, a novel "aggregating bundles of clusters" (ABC) procedure was applied to separate cholestatic from non-cholestatic drugs and model toxicants in the Johnson & Johnson (Janssen) rat liver toxicogenomics database [3]. Drug-induced cholestasis is an important issue, particularly when a new compound enters the market with this liability, with standard preclinical models often mispredicting this toxicity. Three well-characterized cholestasis-responsive genes (Cyp7a1, Mrp3 and Bsep) were chosen from a previous in-house Janssen gene expression signature; these three genes show differing, non-redundant responses across the 90+ paradigm compounds in our database. Using the ABC procedure, extraneous contributions were minimized in comparisons of compound gene responses. All genes were assigned weights proportional to their correlations with Cyp7a1, Mrp3 and Bsep, and a resampling technique was used to derive a stable measure of compound similarity. The compounds that were known to be associated with rat cholestasis generally had small values of this measure relative to each other but also had large values of this measure relative to non-cholestatic compounds. Visualization of the data with the ABC-derived signature showed a very tight, essentially identically behaving cluster of robust human cholestatic drugs and experimental cholestatic toxicants (ethinyl estradiol, LPS, ANIT and methylene dianiline, disulfiram, naltrexone, methapyrilene, phenacetin, alpha-methyl dopa, flutamide, the NSAIDs--indomethacin, flurbiprofen, diclofenac, flufenamic acid, sulindac, and nimesulide, butylated hydroxytoluene, piperonyl butoxide, and bromobenzene), some slightly less active compounds (3'-acetamidofluorene, amsacrine, hydralazine, tannic acid), some drugs that behaved very differently, and were distinct from both non-cholestatic and cholestatic drugs (ketoconazole, dipyridamole, cyproheptadine and aniline), and many postulated human cholestatic drugs that in rat showed no evidence of cholestasis (chlorpromazine, erythromycin, niacin, captopril, dapsone, rifampicin, glibenclamide, simvastatin, furosemide, tamoxifen, and sulfamethoxazole). Most of these latter drugs were noted previously by other groups as showing cholestasis only in humans. The results of this work suggest that the ABC procedure and similar statistical approaches can be instrumental in combining data to compare toxicants across toxicogenomics databases, extract similarities among responses and reduce unexplained data varation.
PubMed: 28959545
DOI: 10.1016/j.toxrep.2016.01.009