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991.
Lucia Anna Muscarella Raffaela Barbano Vincenzo D'Angelo Massimiliano Copetti Michelina Coco Teresa Balsamo Annamaria la Torre Angelo Notarangelo Michele Troiano Salvatore Parisi Nadia Icolaro Domenico Catapano Vanna Maria Valori Fabio Pellegrini Giuseppe Merla Massimo Carella Vito Michele Fazio Paola Parrella 《Epigenetics》2011,6(3):317-325
992.
Fusarium avenaceum isolates from wheat, rye, barley, triticale, corn and potato formed substance with yellow fluorescence with properties similar to citrinin. Pathogenicity of 17 isolates tested against cereals seedlings was weaker than F. culmorum isolates; one isolate only was strong, two medium and the remaining 82 % were very weak or non pathogenic. 相似文献
993.
Paola Di Natale Carmela Di Domenico Guglielmo R D Villani Angelo Lombardo Antonia Follenzi Luigi Naldini 《European journal of biochemistry》2002,269(11):2764-2771
Mucopolysaccharidosis type I (MPS I) results from a deficiency in the enzyme alpha-L-iduronidase (IDUA), and is characterized by skeletal abnormalities, hepatosplenomegaly and neurological dysfunction. In this study, we used a late generation lentiviral vector to evaluate the utility of this vector system for the transfer and expression of the human IDUA cDNA in MPS I fibroblasts. We observed that the level of enzyme expression in transduced cells was 1.5-fold the level found in normal cells; the expression persisted for at least two months. In addition, transduced MPS I fibroblasts were capable of clearing intracellular radiolabeled glycosaminoglycan (GAG). Pulse-chase experiments on transduced fibroblasts showed that the recombinant enzyme was synthesized as a 76-kDa precursor form and processed to a 66-kDa mature form; it was released from transduced cells and was endocytosed into a second population of untreated MPS I fibroblasts via a mannose 6-phosphate receptor. These results suggest that the lentiviral vector may be used for the delivery and expression of the IDUA gene to cells in vivo for treatment of MPS I. 相似文献
994.
Béatrice Mathiot Angelo Perani Dominique Dumas Michel Maugras Jacques Didelon Jean-François Stoltz 《Cytotechnology》1993,11(1):41-48
Hybridoma cell growth and monoclonal antibody production were investigated with a laboratory-made system in which cells were grown in dialysis tubing (MW cut-off 25 kD). The dialysis system contained 10 ml of cell suspension and was immersed in 200 ml of culture medium which when replaced or was at 4-day intervals. With this system, monoclonal antibody concentrations similar to those observed in ascites (concentrations in the order of one gramme per liter) were obtained. With no medium replacement, the antibody production was 3.3 g/l and the cell productivity 3.2×10–8 g of IgM produced per cell in one minute. With medium replacement the antibody production was higher, 4.4 g/l but the cell productivity was lower, 1.49×10–8 g per cell in one minute. Cells cultivated in non-optimized conditions were better producers than cells growing in a good environment.Abbreviations FCS
fetal calf serum
- Ig
immunoglobulin
- MAb
monoclonal antibody
- MW
molecular weight
- MWCO
molecular weight cut off
- RM
replaced medium
- NRM
non replaced medium 相似文献
995.
Summary The chromosome complement and some karyological features were investigated in the pelagic amphipod Hyperiella dilatata Stebbing 1888 from the Ross Sea (Antarctica). The diploid karyotype consists of 48 metacentric and 10 submetacentric elements (2n = 58). The presence of secondary constrictions and supernumerary chromosomes is described. Available chromosome numbers of Hyperiidea exhibit a wide range of distribution, among which Hyperiella dilatata is the closest to the modal number of other amphipods. 相似文献
996.
Annarosa Arcangel Laura Faravelli Laura Bianchi Barbara Rosati Angela Gritti Angelo Vescovy Enzo Wanke Massimo Olivotto 《Cell communication & adhesion》1996,4(4):369-385
Changes in the resting potential (Vrest) and in the underlying ionic conductances were measured by the patch-clamp technique in SH-SY5Y human neuroblastoma cells exposed to substrate-bound or soluble Laminin (bLN: sLN), as compared to integrin-independent substrates (polylysine (PL); bovine serum albumin (BSA)). While PL and BSA were ineffective, both forms of LN caused an early (5-15 min) activation of a peculiar type of Inwardly Rectifying K- current (I,ir) characterised by a voltage-dependent inactivation in the range of membrane potentials around —50/0 mV. Iir was blocked by Cs+ ions and by the antiarrhythmic drug E-4031, a specific inhibitor of the HERG-codified channels. In cells adherent to bLN, I,ir potentiation (85%) persisted for 90-120 min and was accompanied by a similar, but transient, increase in the leakage conductance (Gl). Successively, the persistence of a high Iir conductance and the decrease of Gl progressively bring Vrest from -12 to -30 mV in about 120 min. On the other hand, in cells adherent to PL, exposure to sLN produced a similar but not persistent activation of Iir, without any increase in Gl: this caused a rapid, transient hyperpolarisation of Vrest The effects of bLN and sLN were mimicked by antibodies raised against the integrin β1 subunit, suggesting a specific integrin-mediated mechanism. In fact, when bound to the culture dishes, these antibodies simultaneously activated the Iir and Gl, whereas in soluble form they only activated Iir. Cells adherent to bLN emitted neurites, a process impaired by the block of Iir by E-4031 and Cs+. On the whole data suggest that the integrin-mediated activation of Iir plays a crucial role in the commitment to neuritogenesis of neuroblastoma cells, independently on the effects of this activation on Vrest. 相似文献
997.
998.
Fulvio Lauretani Cosimo Roberto Russo Stefania Bandinelli Benedetta Bartali Chiara Cavazzini Angelo Di Iorio Anna Maria Corsi Taina Rantanen Jack M Guralnik Luigi Ferrucci 《Journal of applied physiology》2003,95(5):1851-1860
Sarcopenia, the reduction of muscle mass and strength that occurs with aging, is widely considered one of the major causes of disability in older persons. Surprisingly, criteria that may help a clinician to identify persons with impaired muscle function are still lacking. Using data from a large representative sample of the general population, we examined how muscle function and calf muscle area change with aging and affect mobility in men and women free of neurological conditions. We tested several putative indicators of sarcopenia, including knee extension isometric torque, handgrip, lower extremity muscle power, and calf muscle area. For each indicator, sarcopenia was considered to be present when the measure was >2 SDs below the mean. For all four measures, the prevalence of sarcopenia increased with age, both in men and women. The age-associated gradient in prevalence was maximum for muscle power and minimum for calf-muscle area. However, lower extremity muscle power was no better than knee-extension torque or handgrip in the early identification of poor mobility, defined either as walking speed <0.8 m/s or inability to walk at least 1 km without difficulty and without developing symptoms. Optimal cutoff values that can be used in the clinical practice to identify older persons with poor mobility were developed. The findings of the study lay the basis for a cost-effective, clinical marker of sarcopenia based on a measure of isometric handgrip strength. Our findings should be verified in a longitudinal study. 相似文献
999.
1000.
Angelo Abbondandolo Anne Weyer Henri Heslot Micheline Lambert 《Journal of bacteriology》1971,108(3):959-963
Observation of the growth of some adenineless mutants of Schizosaccharomyces pombe on six substituted purine analogs leads to the hypothesis that an enzyme is present which catalyzes the conversion of these analogs into hypoxanthine. The enzyme adenase (adenine aminohydrolase, EC 3.5.4.2) has been found to be active in cell-free extracts of S. pombe. Results are reported which are in agreement with the hypothesis that this enzyme is responsible for the in vivo utilization of 6-chloropurine. This evidence comes mainly from a study of adenine aminohydrolase in two mutants selected for partial inability to grow on 6-chloropurine. 相似文献