Comparative cytologic features of adenocarcinoma in situ of the uterine cervix

The cytologic findings in 30 cases of adenocarcinoma in situ (AIS) and related lesions of the cervix were compared with those in 13 cases of cervical invasive adenocarcinoma and 8 cases of cervical nonneoplastic conditions that mimicked AIS cytologically. Although there was considerable overlap, the presence of large cells with irregular nuclei and uneven chromatin distribution in smears containing no normal endocervical cells helped to distinguish invasive adenocarcinoma from AIS. The presence of "feathering," rosettes, mitotic figures and very crowded nuclei with scant cytoplasm and without cilia helped distinguish AIS from benign conditions.     

Rice yields as influenced by Azolla N2 fixation and urea N-fertilization

Application of 0, 30, 60, 90 and 120 kg N ha^–1 of urea (U) in split doses with (and without)Azolla pinnata, R. Brown was studied for three consecutive seasons under planted field condition. Fresh weight (FW), acetylene reduction activity (ARA) and N yield of Azolla were found to be maximum 14 days after inoculation (DAI). Among the different treatments, maximum Azolla growth was recorded in no N control. The FW, ARA and N yield of Azolla were inhibited increasingly with the increase in N levels. Irrespective of season, FW and N yield of Azolla were inhibited only a small extent with 90 kg N ha^–1 U, beyond which the inhibition was pronounced. ARA was inhibited only slightly up to 60 kg N ha^–1 of U. Grain yield and crop N uptake of rice increased significantly up to 90 kg N ha^–1 of U (alone or in combination with Azolla) in the dry seasons (variety IR 36) and up to 60 kg N ha^–1 U in the wet season (variety CR 1018).     

Extrachromosomal inheritance of nalidixic acid resistance in the petite negative yeast Schizosaccharomyces pombe

Summary Spontaneous mutants resistant to nalidixic acid (NAL) were isolated from the petite negative yeast Schizosaccharomyces pombe (S. pombe). One of these mutants, resistant to 200 g/ml NAL, nal ^r–Y13, was characterized both genetically and biochemically. The extrachromosomal inheritance of this mutation was demonstrated both by mitotic segregation and by mitotic haploidization analysis. In the wild-type, NAL at a concentration of 100 g/ml almost completely inhibits incorporation of [¹⁴C]adenine in total DNA as well as in mitochondrial DNA. In the NAL-resistant mutant both total DNA synthesis and mitochondrial DNA synthesis were resistant to the drug. These results are discussed in view of previously published findings on the close interaction between the two DNA synthesizing systems in S. pombe.     

Synthesis of mitochondrial DNA during the cell cycle of the petite negative yeast Schizosaccharomyces pombe

Summary Synthesis of mitochondrial DNA (mitDNA) and nuclear DNA (nucDNA) during growth of synchronously dividing cultures of Schizosaccharomyces pombe (S. pombe) was followed by pulse labelling with radioactive adenine and determination of its rate of incorporation into total protoplast DNA and into the DNA of DNase-treated mitochondria at different stages of the cell cycle. It could be demonstrated that both mitDNA and nucDNA were synthesised discontinuously and at different points in the cell cycle.     

Nucleo-cytoplasmic interactions in the petite negative yeast Schizosaccharomyces pombe

Summary In the petite positive yeast, Saccharomyces cerevisiae, cycloheximide selectively inhibits protein synthesis on cytoplasmic ribosomes, and, as a consequence, nuclear DNA synthesis. Mitochondrial DNA, however, is synthesized for 4–6 h after cessation of protein synthesis. In this paper we show that in contrast to Saccharomyces cerevisiae, synthesis of mitochondrial and nuclear DNA is tightly coordinated in the petite negative yeast Schizosaccharomyces pombe, since inhibition of cytoplasmic protein synthesis leads immediately to cessation of both nuclear and mitochondrial DNA synthesis.Dedicated to Prof. Dr. F. Kaudewitz on occasion of his 60th birthday     

Formation and characterization of glutamate dehydrogenase monolayers on silicon supports

In this paper we have tested two different procedures (the "three-step" and the "four-step" procedures) for the covalent immobilization of glutamate dehydrogenase (GDH) onto silicon supports. Atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FT-IR), fluorescence spectroscopy and an enzymatic assay were used to probe the structure and activity of the immobilized enzyme. Our results demonstrate that coupling through the "three-step" procedure does not significantly affect either the fold pattern or the activity of the enzyme, suggesting that this method could be ideally suited to the development of high quality monolayers for use in enzyme-based planar biosensors.     

Interleukin-8 induces nuclear transcription factor-kappaB through a TRAF6-dependent pathway

Considering the potential role of interleukin-8 (IL-8) in inflammation, angiogenesis, tumorigenesis, and metastasis, we investigated the molecular mechanism involved in IL-8-mediated signaling. In this report we provide evidence that like TNF, an inducer of NF-kappaB and also a NF-kappaB-dependent gene product, IL-8 induces NF-kappaB in a unique pathway. IL-8 induces NF-kappaB activation in a dose-dependent manner in different cell types as detected by a DNA-protein binding assay. IL-8 induces NF-kappaB-dependent reporter gene expression as well as ICAM-1, VCAM-1, and Cox-2 expression. IL-8 also induces IkappaBalpha phosphorylation followed by degradation and p65 translocation. IL-8 induces c-Jun N-terminal kinase (JNK) and mitogen-activated protein kinase (MAPK) in a dose- and time-dependent manner. IL-8-induced NF-kappaB activation is for the most part unaltered when cells are transfected with dominant-negative TRADD, FADD, or TRAF2, but is inhibited with dominant-negative TRAF6-, NIK-, IKK-, or IkappaBalpha-transfected cells. The data suggest that IL-8-induced NF-kappaB activation proceeds through a TRAF2-independent but TRAF6-dependent pathway, followed by recruitment of IRAK and activation of IKK. IL-8-induced NF-kappaB activation is not observed in a cell-permeable peptide that has TRAF6 binding motif-treated cells or IRAK-deficient cells. IL-8-induced NF-kappaB activation proceeds mostly through interaction with TRAF6 and partially through the Rho-GTPase pathways. This is the first report that IL-8 induces NF-kappaB in a distinct pathway, and activation of NF-kappaB and its dependent genes may be one of the pathways of IL-8-induced inflammation and angiogenesis.     

Synthesis of some pyrazole derivatives and preliminary investigation of their affinity binding to P-glycoprotein

A series of substituted pyrazolines were synthesized and evaluated for their anticancer activity and for their ability to inhibit P-glycoprotein-mediated multidrug resistance by direct binding to a purified protein domain containing an ATP-binding site and a modulator interacting region. Compounds 2a and e have been found to bind to P-glycoprotein with greater affinity.     

Novel 1,4-dihydropyridine induces apoptosis in human cancer cells through overexpression of Sirtuin1

1,4-Dihydropyridines (1,4-DHPs) are important as a class of heterocyclic compounds that exhibit wide range of biological actions. Many of its derivatives are already characterized as medicinally important drugs and used worldwide. In this study, we have screened some novel Hantzsch 1,4-DHP compounds using both in silico (QSAR and Pharmacophore) and in vitro (cytotoxic screening). 1,4-DHP showed selective cytotoxicity against five human cancerous cell lines; A375, A549, HeLa, HepG2 and SH-SY5Y but limited effect towards normal skin keratinocyte (HaCaT), lung fibroblast (WL-38) and healthy peripheral blood mononuclear cells. In A375 and HepG2 cells, one of the 1,4-DHP derivative (DHP-8) was found to inhibit cell proliferation, and simultaneously increased the apoptotic population as well as mitochondrial membrane depolarization. Furthermore, the mitochondrial signal was triggered with the activation of cleaved Caspase9, Caspase3 and PARP. The treatment with DHP-8 also increased the expression level of SIRT1, subsequently decreasing the level of pAKT^ser473 and survivin. Reduced pAKT^ser473 expression led to decrease the phosphorylated inactive form of GSK3β^ser9 and as a result, proteasomal degradation of Mcl-1 occurred in both the cell lines. Here, we suggest that the apoptotic effect of DHP-8 in A375 and HepG2 cells was mediated by AKT and survivin pathways through SIRT1 activation. The involvement of DHP-8 in SIRT1 activation was further verified by co-treatment of nicotinamide with DHP-8 in both A375 and HepG2 cells. Overall, this study emphasizes the possible potential and therapeutic role of DHP-8 in skin and liver cancer.