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排序方式: 共有559条查询结果,搜索用时 250 毫秒
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Alexander Mironov Antonino Colanzi Maria Giuseppina Silletta Giusy Fiucci Silvio Flati Aurora Fusella Roman Polishchuk Alexander Mironov Jr. Giuseppe Di Tullio Roberto Weigert Vivek Malhotra Daniela Corda Maria Antonietta De Matteis Alberto Luini 《The Journal of cell biology》1997,139(5):1109-1118
We have investigated the role of the ADP- ribosylation induced by brefeldin A (BFA) in the mechanisms controlling the architecture of the Golgi complex. BFA causes the rapid disassembly of this organelle into a network of tubules, prevents the association of coatomer and other proteins to Golgi membranes, and stimulates the ADP-ribosylation of two cytosolic proteins of 38 and 50 kD (GAPDH and BARS-50; De Matteis, M.A., M. DiGirolamo, A. Colanzi, M. Pallas, G. Di Tullio, L.J. McDonald, J. Moss, G. Santini, S. Bannykh, D. Corda, and A. Luini. 1994. Proc. Natl. Acad. Sci. USA. 91:1114–1118; Di Girolamo, M., M.G. Silletta, M.A. De Matteis, A. Braca, A. Colanzi, D. Pawlak, M.M. Rasenick, A. Luini, and D. Corda. 1995. Proc. Natl. Acad. Sci. USA. 92:7065–7069). To study the role of ADP-ribosylation, this reaction was inhibited by depletion of NAD+ (the ADP-ribose donor) or by using selective pharmacological blockers in permeabilized cells. In NAD+-depleted cells and in the presence of dialized cytosol, BFA detached coat proteins from Golgi membranes with normal potency but failed to alter the organelle's structure. Readdition of NAD+ triggered Golgi disassembly by BFA. This effect of NAD+ was mimicked by the use of pre–ADP- ribosylated cytosol. The further addition of extracts enriched in native BARS-50 abolished the ability of ADP-ribosylated cytosol to support the effect of BFA. Pharmacological blockers of the BFA-dependent ADP-ribosylation (Weigert, R., A. Colanzi, A. Mironov, R. Buccione, C. Cericola, M.G. Sciulli, G. Santini, S. Flati, A. Fusella, J. Donaldson, M. DiGirolamo, D. Corda, M.A. De Matteis, and A. Luini. 1997. J. Biol. Chem. 272:14200–14207) prevented Golgi disassembly by BFA in permeabilized cells. These inhibitors became inactive in the presence of pre–ADP-ribosylated cytosol, and their activity was rescued by supplementing the cytosol with a native BARS-50–enriched fraction. These results indicate that ADP-ribosylation plays a role in the Golgi disassembling activity of BFA, and suggest that the ADP-ribosylated substrates are components of the machinery controlling the structure of the Golgi apparatus. 相似文献
3.
V. Cusumano G.B. Costa R. Trifiletti R.A. Merendino G. Mancuso 《FEMS immunology and medical microbiology》1995,10(2):151-156
Abstract Contamination of food with mycotoxins is a major health problem. Impairment of several immune functions has been repeatedly reported in animals fed with contaminated fodder. Since the liver is a major target of toxicity by aflatoxins, the effects of aflatoxins B1, and its hepatic metabolites Q1 and M1 on Kupffer cell function was investigated in vitro. Aflatoxin B1 induced significant ( P < 0.05) inhibition of phagocytosis, intracellular killing of Candida albicans , and intrinsic anti-Herpes virus activity at concentrations as low as 0.01 pg ml−1 . Aflatoxin Q1 and M1 had similar effects on phagocytosis and microbicidal activity, but were two- to ten-fold less potent than aflatoxin B1 . 相似文献
4.
A Natalello D Ami M Collini L D'Alfonso G Chirico G Tonon S Scaramuzza R Schrepfer SM Doglia 《PloS one》2012,7(8):e42511
The limited stability of proteins in vitro and in vivo reduces their conversion into effective biopharmaceuticals. To overcome this problem several strategies can be exploited, as the conjugation of the protein of interest with polyethylene glycol, in most cases, improves its stability and pharmacokinetics. In this work, we report a biophysical characterization of the non-pegylated and of two different site-specific mono-pegylated forms of recombinant human methionyl-granulocyte colony stimulating factor (Met-G-CSF), a protein used in chemotherapy and bone marrow transplantation. In particular, we found that the two mono-pegylations of Met-G-CSF at the N-terminal methionine and at glutamine 135 increase the protein thermal stability, reduce the aggregation propensity, preventing also protein precipitation, as revealed by circular dichroism (CD), Fourier transform infrared (FTIR), intrinsic fluorescence spectroscopies and dynamic light scattering (DLS). Interestingly, the two pegylation strategies were found to drastically reduce the polydispersity of Met-G-CSF, when incubated under conditions favouring protein aggregation, as indicated by DLS measurements. Our in vitro results are in agreement with preclinical studies, underlining that preliminary biophysical analyses, performed in the early stages of the development of new biopharmaceutical variants, might offer a useful tool for the identification of protein variants with improved therapeutic values. 相似文献
5.
Grossly Defective nef Gene Sequences in a Human Immunodeficiency Virus Type 1-Seropositive Long-Term Nonprogressor 总被引:6,自引:3,他引:6
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Roberto Salvi Anna Rosa Garbuglia Antonino Di Caro Simonetta Pulciani Francesco Montella Arrigo Benedetto 《Journal of virology》1998,72(5):3646-3657
We have been investigating a long-term nonprogressor who was found to be human immunodeficiency virus type 1 (HIV-1) seropositive in 1985 and has survived with stable CD4+ T-cell counts (>1,000 CD4 cells/μl) without any AIDS-related illness. We have previously reported that repeated attempts to measure HIV-1 RNA in the peripheral mononuclear cells obtained from this subject have invariably failed. In the present study, we have analyzed the molecular nature of the HIV-1 quasispecies infecting this patient by PCR amplification of two proviral regions, the 5′ long terminal repeat (5′LTR)/gag leader and the nef gene, directly from fresh uncultured peripheral mononuclear cells, followed by length polymorphism analysis (with 1994, 1995, and 1996 samples) and sequencing (with a 1996 sample). Only proviral forms with nef deletions were revealed by length polymorphism analysis in samples from all three time points. Sequence analysis of the nef gene from the 1996 sample confirmed the presence of similar proviral quasispecies characterized by the presence of several deletions located in the nef-alone and the nef/U3 overlapping regions. Length polymorphism analysis of the 5′LTR/gag leader region suggested the existence of two major quasispecies populations, one characterized by the presence of forms carrying deletions in the U3 region and the other showing a completely intact, full-length 5′LTR. Evidence of the role of nef gene defects in long-term survival of HIV-1-infected patients has been provided so far in two independent investigations involving patients infected with HIV through blood transfusion. Here we show the existence of a similar condition in a subject who acquired HIV-1 seropositivity through the sexual route. 相似文献
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7.
A molecular beacon, bead-based assay for the detection of nucleic acids by flow cytometry 总被引:3,自引:1,他引:2
Horejsh D Martini F Poccia F Ippolito G Di Caro A Capobianchi MR 《Nucleic acids research》2005,33(2):e13
Molecular beacons are dual-labelled probes that are typically used in real-time PCR assays, but have also been conjugated with solid matrices for use in microarrays or biosensors. We have developed a fluid array system using microsphere-conjugated molecular beacons and the flow cytometer for the specific, multiplexed detection of unlabelled nucleic acids in solution. For this array system, molecular beacons were conjugated with microspheres using a biotin-streptavidin linkage. A bridged conjugation method using streptavidin increased the signal-to-noise ratio, allowing for further discrimination of target quantitation. Using beads of different sizes and molecular beacons in two fluorophore colours, synthetic nucleic acid control sequences were specifically detected for three respiratory pathogens, including the SARS coronavirus in proof-of-concept experiments. Considering that routine flow cytometers are able to detect up to four fluorescent channels, this novel assay may allow for the specific multiplex detection of a nucleic acid panel in a single tube. 相似文献
8.
Girolamo A. Vitello Francesco Calì Mirella Vinci Carmela Scuderi Francesca LEpiscopo Antonino Musumeci Sebastiano A. Musumeci Antonio G. Nicotera 《Journal of musculoskeletal & neuronal interactions》2020,20(4):610
Spinal muscular atrophy (SMA) refers to a group of genetic neuromuscular disorders affecting lower motor neurons causative of numerous phenotypes. To date, according to the age of onset, maximum muscular activity achieved, and life expectation four types of SMA are recognized, all caused by mutations in the SMN1 gene with SMN2 copy number influencing disease severity. Herein, we describe the case of a 31-year-old young male with normal psychomotor development who has experienced fatigue, cramps, and muscle fasciculations in the lower limbs for a period of 2 months. Based on electrophysiological and clinical findings we performed SMA genetic, clinical exome and RNA expression of candidate genes which led us to suggest SMN1-SMN2 genes [(2+0) and (0+0)] combination as possibly being implicated in the phenotype. 相似文献
9.
Abstract Cardopatum corymbosum is a perennial hemicryptophyta species living on erosion-prone steep slopes where it forms very small, scattered communities that resist soil erosion. The aim of this study was to understand better the life cycle of this species before suggesting its use for eco-engineering purposes to stop soil erosion. We examined anatomical preparations with a light microscope, and plant anatomy was reconstructed by examining sequential cross sections of the stem cut from the shoot apex to the root collar. A single sprout above the root collar produces a rosette of leaves at the beginning of spring and a floral axis at the end of summer. The leaves and the floral axis die at the end of summer, whereas the basal portion of the new stem remains alive and forms, together with the root system, the perennial portion of this plant. This stem zone is named “transition zone” and presents leaf traces converging in the centre where they give rise to a vascular cylinder with a cambium ring dividing a secondary xylem from a secondary phloem. New buds form in the cortex of the transition zone that are quiescent and are not visible externally until the following spring when they resume growth and generate a new sprout. These buds should be considered adventitious because: (1) they form independently of leaves; and (2) their annual production could represent the plant's response to ensure its survival after the loss of the above-ground portion of the stem. Given the efficient resprouting strategy coupled with a perennial root system, C. corymbosum is a good candidate for bio-engineering applications against the soil erosion typical of steep slopes in Mediterranean climates. This species could be considered for intensive re-vegetation in order to produce a protective soil covering. 相似文献
10.
Polito Francesca Famà Fausto Oteri Rosaria Raffa Giovanni Vita Gianluca Conti Alfredo Daniele Sacco Macaione Vincenzo Passalacqua Marcello Cardali Salvatore Di Giorgio Rosa Maria Gioffrè Maria Angileri Flavio F. Germanò Antonino Aguennouz M’Hammed 《Molecular biology reports》2020,47(4):2941-2949
Molecular Biology Reports - TBI is the main cause of death and disability in individuals aged 1–45 in Western countries. One of the main challenges of TBI at present is the lack of specific... 相似文献