Synthesis, structural characterization, antimicrobial and cytotoxic effects of aziridine, 2-aminoethylaziridine and azirine complexes of copper(II) and palladium(II).

The synthesis, spectroscopic and X-ray structural characterization of copper(II) and palladium(II) complexes with aziridine ligands as 2-dimethylaziridine HNCH2CMe2 (a), the bidentate N-(2-aminoethyl)aziridines C2H4NC2H4NH2 (b) or CH2CMe2NCH2CMe2NH2 (c) as well as the unsaturated azirine NCH2CPh (d) are reported. Cleavage of the cyclometallated Pd(II) dimer [μ-Cl(C6H4CHMeNMe2-C,N)Pd]2 with ligand a yielded compound [Cl(NHCH2CMe2)(C6H4CHMe2NMe2-C,N)Pd] (1a). The reaction of the aziridine complex trans-[Cl2Pd(HNC2H4)2] with an excess of aziridine in the presence of AgOTf gave the ionic chelate complex trans-[(C2H4NC2H4NH2-N,N′)2Pd](OTf)2 (2b) which contains the new ligand b formed by an unexpected insertion and ring opening reaction of two aziridines (“aziridine dimerization”). CuCl2 reacted in pure HNC2H4 or HNCH2CMe2 (b) again by “dimerization” to give the tris-chelated ionic complex [Cu(C2H4NC2H4NH2-N,N′)3]Cl2 (3b) or the bis-chelated complex [CuCl(C2H2Me2NC2H2Me2NH2-N,N′)2]Cl (4c). By addition of 2H-3-phenylazirine (d) to PdCl2, trans-[Cl2Pd(NCH2CPh)2] (5d) was formed. All new compounds were characterized by NMR, IR and mass spectra and also by X-ray structure analyses (except 3b). Additionally the cytotoxic effects of these complexes were examined on HL-60 and NALM-6 human leukemia cells and melanoma WM-115 cells. The antimicrobial activity was also determined. The growth of Gram-positive bacterial strains (S. aureus, S. epidermidis, E. faecalis) was inhibited by almost all tested complexes at the concentrations of 37.5–300.0 μg mL−1. However, MIC values of complexes obtained for Gram-negative E. coli and P. aeruginosa, as well as for C. albicans yeast, mostly exceeded 300 μg mL−1. The highest antibacterial activity was achieved by complexes 1a and 2b. Complex 2b also inhibited the growth of Gram-negative bacteria. Graphical abstract: Synthesis, structural characterization, antimicrobial and cytotoxic effects of aziridine, 2-aminoethylaziridine and azirine complexes of copper(ii) and palladium(ii

Ameloblastic neoplasia spectrum : a cross-sectional study of MMPS expression and proliferative activity

Objective. To compare the proliferation and the expression of matrix metalloproteinases (MMPs; MMP-2 and MMP-9) in solid and unicystic ameloblastomas with ameloblastic carcinomas. Study Design.Five cases of ameloblastic carcinoma (AC), 18 cases of solid ameloblastoma (SA), and seven of unicystic ameloblastoma (UA) were selected. The immunohistochemical expression of MMPs was assessed by the percentage of positive tumor cells and stained stroma. The mean argyrophilic nucleolar organizer region (AgNOR) and the percentage of cells with more than one AgNOR per nucleus were evaluated. Results. Statistically significant higher mean AgNOR was observed in AC than in SA and UA. MMP-2 was expressed similarly in tumor and stroma among groups. MMP-9 was higher in the stroma of SA than that of UA (P = .0484). Conclusions. The cell proliferation was related to the greater aggressiveness of AC. High expression of MMP-2 and MMP-9 in all lesions highlighted the importance of these enzymes in the biology of ameloblastic tumors

Surgical findings in cryptorchidism in children with Zika-related microcephaly: a case series.

BACKGROUND: Complications in the urinary tract related to congenital Zika syndrome have recently been reported. One complication, cryptorchidism, has been reported by the Microcephaly Epidemic Research Group/MERG, in Pernambuco/Brazil. The present article describes for the first time the surgical findings in a case series of boys with Zika-related microcephaly and cryptorchidism, who underwent surgical testicular exploration as a contribution to better understand the possible mechanisms involved in gonads formation and descent. METHODS: A total of 7 children (11 testicular units), aged 3 to 4 years, were submitted to inguinal or scrotal orchidopexy for the treatment of palpable cryptorchidism between August 2019 and January 2020. Characteristics of the gonads and its annexes related to appendixes, testis-epididymis dissociation, gubernacular insertion, and associated hydroceles and/or hernias were described. Measures in centimetres were taken for volume calculate. RESULTS: We found a low prevalence of testicular and epididymal appendix (66.7%), a high prevalence of testis-epididymis dissociation (55.6%), low mean testicular volume for their ages (lower for older boys) and ectopic gubernacular insertion in all cases. There was no evidence of associated hydroceles and/or hernias in any case. No surgical complication was registered or reported, and all explored gonads were properly placed in the scrotal sac. CONCLUSIONS: We herein describe the surgical findings of these children's orchidopexies and discuss the possible mechanisms of viral action in embryogenesis and postnatal growth and development of the testes and annexes. These children need to be followed over time due to the higher risk of testicular atrophy and malignancy. Surgical timing seems to be relevant to avoid loss of testicular volume

Molecular imaging of glycan chains couples cell-wall polysaccharide architecture to bacterial cell

Biopolymer composite cell walls maintain cell shape and resist forces in plants, fungi and bacteria. Peptidoglycan, a crucial antibiotic target and immunomodulator, performs this role in bacteria. The textbook structural model of peptidoglycan is a highly ordered, crystalline material. Here we use atomic force microscopy (AFM) to image individual glycan chains in peptidoglycan from Escherichia coli in unprecedented detail. We quantify and map the extent to which chains are oriented in a similar direction (orientational order), showing it is much less ordered than previously depicted. Combining AFM with size exclusion chromatography, we reveal glycan chains up to 200 nm long. We show that altered cell shape is associated with substantial changes in peptidoglycan biophysical properties. Glycans from E. coli in its normal rod shape are long and circumferentially oriented, but when a spheroid shape is induced (chemically or genetically) glycans become short and disordered