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1.
Purified murein from Thiobacillus neapolitanus was poorly digested by lysozyme. It's sensitivity to the enzyme greatly increased after N-acetylation. The murein was found to contain 30 to 35% glucosamine residues lacking N-acetyl groups. It also contained phosphomuramic acid. Further modifications included amidation of diaminopimelic acid in the peptide side chains and a low alanine content. None of these modifications were found in the murein of another sulphur bacterium, Thiobacillus versutus. 相似文献
2.
The research was designed to investigate the moderating effect of some personality traits on subjective distress caused by daily hassles. The traits were internal locus of control, repression, ego strength, and barrier (as studied and defined by S. Fisher). The last two variables were negatively correlated both with the somatic and emotional distress indications and with the frequency of hassles reportED; internal locus of control showed an inverse relationship only with frequency of hassles. The hypothesis is formulated that ego strength and barrier are personality factors influencing not only the outcomes of coping (ie the stress response), but also event appraisal. 相似文献
3.
Functional topography of discrete domains of human CD38 总被引:6,自引:0,他引:6
Ausiello CM Urbani F Lande R la Sala A Di Carlo B Baj G Surico N Hilgers J Deaglio S Funaro A Malavasi F 《Tissue antigens》2000,56(6):539-547
4.
Chiurillo MA Crisante G Rojas A Peralta A Dias M Guevara P Añez N Ramírez JL 《Clinical and diagnostic laboratory immunology》2003,10(5):775-779
We used the species specificity and repetitious nature of subtelomeric kinetoplastida sequences to generate a duplex PCR assay for the simultaneous detection of Trypanosoma cruzi and Trypanosoma rangeli in experimentally and naturally infected triatomine (Reduviid) bugs and in infected human subjects. The assay was species specific and was capable of detecting 1/20th of T. cruzi and 1/4th of T. rangeli cell equivalents without complementary hybridization. In addition, the PCR-based assay was robust enough for direct application to difficult biological samples such as Reduviid feces or guts and was capable of recognizing all T. cruzi and T. rangeli strains and lineages. Because the assay primers amplify entirely different target sequences, no reaction interference was observed, facilitating future adaptation of this assay to an automated format. 相似文献
5.
Eugenio I. Vivas Andreina Liendo Karl Dawidowicz Toms Istúriz 《Journal of basic microbiology》1994,34(2):117-122
It is known that two gluconokinases are inducibly expressed during the utilization of gluconate by E. coli. One is thermoresistant (activity stable for 3 h at 30 °C) and the other thermosensitive (losses 75% or more of its activity under the above conditions). The thermoresistant gluconokinase (EC 2.7.1.12) was isolated, purified and characterized for the first time from the E. coli mutant Ca26, a K12 derivative which lacks the thermosensitive activity. The enzyme was purified 43 fold with a recovery of 11%. The Mr of the enzyme was 100 kDa with three equal subunits of approximately 29.5 kDa. The enzyme exhibited Michaelis-Menten kinetics and the Km values for gluconate and ATP were 0.02 mM and 0.045 mM respectively. 相似文献
6.
Krzyzak AT Jasiński A Weglarz WP Adamek D Sagnowskil P Baj M 《Acta neurobiologiae experimentalis》2005,65(3):255-264
Magnetic Resonance Diffusion Tensor Imaging (DTI) of the control and traumatic injured spinal cord of a rat in vitro is reported. Experiments were performed on excised spinal cords from 10 Wistar rats, using a home-built 6.4 T MR microscope. MRI and histopathological results were compared. Presented results show that DTI of the spinal cord, perfused with formalin 10 minutes after the injury, can detect changes in water diffusion in white matter (WM) and in gray matter (GM), in areas extending well beyond the region of direct impact. Histology of neurons of the GM shows changes that can be attributed to ischemia. This is in agreement with the observed decrease of diffusion in the injured regions, which may be attributed to the cytotoxic edema due to ischemia. However, the diffusion changes in highly anisotropic WM seem to be caused by a direct action of mechanical force of impact, which significantly distorts the nerve fibers. 相似文献
7.
Daniela Vitucci Angela Amoresano Marcella Nunziato Simona Muoio Andreina Alfieri Giovannangelo Oriani Luca Scalfi Luigi Frusciante Maria Manuela Rigano Piero Pucci Luigi Fontana Pasqualina Buono Francesco Salvatore 《Nutrients》2021,13(4)
The isoforms of lycopene, carotenoids, and their derivatives including precursors of vitamin A are compounds relevant for preventing chronic degenerative diseases such as cardiovascular diseases and cancer. Tomatoes are a major source of these compounds. However, cooking and successive metabolic processes determine the bioavailability of tomatoes in human nutrition. To evaluate the effect of acute/chronic cooking procedures on the bioavailability of lycopene and carotene isoforms in human plasma, we measured the blood levels of these compounds and of the serum antioxidant potential in volunteers after a meal containing two different types of tomato sauce (rustic or strained). Using a randomized cross-over administration design, healthy volunteers were studied, and the above indicated compounds were determined by HPLC. The results indicate an increased bioavailability of the estimated compounds and of the serum antioxidant potential with both types of tomato purée and the subsequently derived sauces (the increase was greater with strained purée). This study sheds light on the content of nutrient precursors of vitamin A and other antioxidant compounds derived from tomatoes cooked with different strategies. Lastly, our study indicates that strained purée should be preferred over rustic purée. 相似文献
8.
Ziaber J Tchórzewski H Chmielewski H Baj Z Paśnik J Kaczmarek J 《Neurologia i neurochirurgia polska》1999,33(4):789-796
Usually neglected is the role of neutrophils in causing of immunological disturbances in patients with multiple sclerosis (MS). Nevertheless, it has been indicated over the recent years that these cells possess a sufficient potential to affect both immune response and inflammation. This potential may result in MS through the process of priming of these cells by proinflammatory cytokines like TNF. We studied TNF and its soluble receptors sp55 and sp75 serum levels and binding of fluorescein isothiocyanate (FITC)-stained TNF by neutrophils. We studied three different groups of MS patients: 10 patients in relapse of the disease, 13 in its remission, and 11 in its chronic progressive form (CP-MS). The control was provided by 14 neurological patients (OND) with non-inflammatory diseases. The performed studies showed higher TNF sp55 and sp75 soluble TNF receptors serum levels in the patients with relapse, comparing with other MS patients and OND. TNF binding by neutrophils of MS patients during relapse was also higher, than other MS patients and OND. These result suggest the preactivation of neutrophils in the relapse of MS. 相似文献
9.
Antonello D’Andrea Juri Radmilovic Stefano Caselli Andreina Carbone Raffaella Scarafile Simona Sperlongano Giampaolo Tocci Tiziana Formisano Francesca Martone Biagio Liccardo Michele D’Alto Eduardo Bossone Maurizio Galderisi Paolo Golino 《The international journal of cardiovascular imaging》2018,34(10):1561-1561
10.
Ettore Porreca Concetta Di Febbo Assunta Pandolfi Andria D''Orazio Nicola Martelli Andrea Mezzetti Franco Cuccurullo Andreina Poggi 《Atherosclerosis》1993,100(2):141-148
We studied the relation between the glutathione (GSH) system and cell proliferation in a model of smooth muscle cells (SMC) derived from the thoracic aorta of 4–6-week-old (young) and 15-month-old (aged) rats. SMC from aged rats showed greater levels of total non-protein thiol compounds (T-SH), increased glutathione transferase (GST) and increased glutathione reductase (GSSG-Red) activities compared with cells from young rats. These changes were associated with an increased proliferation rate of SMC from aged rats. To evaluate the role of GSH on cell proliferation better, a specific inhibitor of gamma-glutamyl-cystein synthetase,
-buthionine-SR-sulphoximine (BSO) was used. BSO showed a dose-dependent inhibition of cell growth, with an IC50 of 10−4 M, after 48–72 h of incubation. Removal of BSO restored cell growth, further suggesting a link between GSH levels and vascular cell proliferation. The inhibitory effect of BSO was about two times greater on SMC from young than on SMC from aged rats. BSO showed 56% inhibition on the proliferation of SMC from young rats and 32% inhibition on SMC from aged rats (10−4 M, 72 h of incubation). A parallel reduction of GSH levels of 38% and 19% for SMC from young and aged rats, respectively, was observed, suggesting that age-related factors may influence the involvement of GSH system in cell proliferation. 相似文献