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Annibale A. Puca Anna Ferrario Anna Maciag Giulia Accardi Anna Aiello Caterina Maria Gambino Giuseppina Candore Calogero Caruso Aryan M. Namboodiri Janardan P. Pandey 《Immunity & ageing : I & A》2018,15(1):26
Background
The aim of this study was to analyse the role of GM allotypes, i.e. the hereditary antigenic determinants expressed on immunoglobulin polypeptide chains, in the attainment of longevity. The role played by immunoglobulin allotypes in the control of immune responses is well known as well as the role of an efficient immune response in longevity achievement. So, it is conceivable that particular GM allotypes may contribute to the generation of an efficient immune response that supports successful ageing, hence longevity.Methods
In order to show if GM allotypes play a role in the achievement of longevity, we typed the DNA of 95 Long-living individuals (LLIs) and 96 young control individuals (YCs) from South Italy for GM3/17 and GM23+/? alleles.Results
To demonstrate the role of GM allotypes in the attainment of longevity we compared genotype and allele frequencies of GM allotypes between LLIs and YCs. A global chi-square test (3?×?2) shows that the distribution of genotypes at the GM 3/17 locus is highly significantly different in LLIs from that observed in YCs (p?<?0.0001). The 2?×?2 chi-square test shows that the carriers of the GM3 allele contribute to this highly significant difference. Accordingly, GM3 allele is significantly overrepresented in LLIs. No significant differences were instead observed regarding GM23 allele.Conclusion
These preliminary results show that GM3 allotype is significantly overrepresented in LLIs. To best of our knowledge, this is the first study performed to assess the role of GM allotypes in longevity. So, it should be necessary to verify the data in a larger sample of individuals to confirm GM role in the attainment of longevity.14.
Naturally occurring neuronal death (NOND) is an essential phenomenon during the course of normal development of the nervous system. Studies in vivo and on organotypic cultures have helped to elucidate the basic histological and ultrastructural features, as well as the main cellular mechanisms of NOND in several areas of the brain. This review examines the existing evidence about the two waves of apoptotic cell death that affect the different types of cerebellar neurons in normal development and certain pathological conditions. The first wave regards neuronal progenitors and pre-migratory neuroblasts, the second post-migratory neuroblasts and mature neurons. The underlying cellular and molecular mechanisms are discussed critically also in the light of their relevance to neurodegenerative diseases. 相似文献
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Wright GE Brown NC Xu WC Long ZY Zhi C Gambino JJ Barnes MH Butler MM 《Bioorganic & medicinal chemistry letters》2005,15(3):729-732
7-Substituted-N(2)-(3,4-dichlorobenzyl)guanines potently and competitively inhibit DNA polymerases IIIC and IIIE from Gram(+) bacteria. Certain derivatives are also competitive inhibitors of DNA polymerase IIIE from Gram(-) bacteria. 相似文献
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Selective hypoxia-cytotoxins based on vanadyl complexes with 3-aminoquinoxaline-2-carbonitrile-N1,N4-dioxide derivatives 总被引:1,自引:0,他引:1
Vieites M Noblía P Torre MH Cerecetto H Laura Lavaggi M Costa-Filho AJ Azqueta A de Cerain AL Monge A Parajón-Costa B González M Gambino D 《Journal of inorganic biochemistry》2006,100(8):1358-1367
A new vanadyl complex with the formula VO(L1)2, where L1=3-amino-6(7)-chloroquinoxaline-2-carbonitrile N(1), N(4)-dioxide, has been synthesized and characterized by elemental analyses, conductometry, fast atom bombardment mass spectroscopy (FAB-MS) and electronic, Fourier transform infrared (FTIR), Raman, nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) spectroscopies. Results were compared with those previously reported for analogous vanadium complexes with other 3-aminoquinoxaline-2-carbonitrile N1,N4-dioxide derivatives as ligands. As an effort to develop novel metal-based selective hypoxia-cytotoxins and to improve bioavailability and pharmacological and toxicological properties of aminoquinoxaline carbonitrile N-dioxides bioreductive prodrugs, the new complex and VO(L)2 complexes, with L=3-amino-6(7)-bromoquinoxaline-2-carbonitrile N1,N4-dioxide (L2) and 3-amino-6(7)-methylquinoxaline-2-carbonitrile N1,N4-dioxide (L3), were subjected to cytotoxic evaluation in V79 cells in hypoxic and aerobic conditions. The complexes resulted in vitro more potent cytotoxins than the free ligands (i.e. potencies P(VO(L1)2)=3.0, P(L1)=9.0 microM) and Tirapazamine (P=30.0 microM) and showed excellent selective cytotoxicity in hypoxia, being no cytotoxic in oxia. In addition, the solubility in hydrophilic solvents resulted significantly higher for the vanadyl complexes than for the free ligands. These results could be indicative that complexation of the quinoxaline-2-carbonitrile N1,N4-dioxide derivatives with vanadium could improve their bioavailability. In addition, a new aspect of the series has been investigated. A detailed comparison of the electrochemical behavior of the free ligands and the complexes has been performed searching for a correlation between reduction potentials of the complexes and their activities and hypoxia selectivities. 相似文献
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Roberto Gambino Gianluca Ruiu Gianfranco Pagano Maurizio Cassader 《Journal of Protein Chemistry》1997,16(3):205-212
The specific binding of digoxigenin-labeled lectins to carbohydrate moieties is used to characterize the carbohydrate chains bound to apolipoprotein H. Our results show that apolipoprotein H is rich in sialic acid linked (2–6) to galactose or N-acetylgalactosamine. Sialic acid is not (2–3)-linked to galactose. Galactose is (1–4)-linked to N-acetylglucosamine and (1–3)-linked to N-acetylgalactosamine. High-mannose N-glycan chains are barely detectable. After N-glycosidase F treatment the molecular weight is substantially reduced. The main band is 32,500 daltons. Carbohydrate O-linked chains, which are mainly represented by sialic acid, are (2–6)-linked to galactose or N-acetylgalactosamine. Galactose is also organized in O-linked chains and it is (1–4)-linked to N-acetylglucosamine and (1–3)-linked to acetylgalactosamine. Biochemical analysis of carbohydrate structures reveals that no specific carbohydrate complex is bound to a single isoform. 相似文献