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111.
Matteo Zurlo Francesco Nicoli Davide Proietto Beatrice Dallan Cristina Zuccato Lucia Carmela Cosenza Jessica Gasparello Chiara Papi Elisabetta d'Aversa Monica Borgatti Chiara Scapoli Alessia Finotti Roberto Gambari 《Journal of cellular and molecular medicine》2023,27(3):353-364
Inhibitors of the mammalian target of rapamycin (mTOR) have been proposed to improve vaccine responses, especially in the elderly. Accordingly, testing mTOR inhibitors (such as Sirolimus) and other geroprotective drugs might be considered a key strategy to improve overall health resilience of aged populations. In this respect, Sirolimus (also known as rapamycin) is of great interest, in consideration of the fact that it is extensively used in routine therapy and in clinical studies for the treatment of several diseases. Recently, Sirolimus has been considered in laboratory and clinical studies aimed to find novel protocols for the therapy of hemoglobinopathies (e.g. β-Thalassemia). The objective of the present study was to analyse the activity of CD4+ and CD8+ T cells in β-Thalassemia patients treated with Sirolimus, taking advantages from the availability of cellular samples of the NCT03877809 clinical trial. The approach was to verify IFN-γ releases following stimulation of peripheral blood mononuclear cells (PBMCs) to stimulatory CEF and CEFTA peptide pools, stimulatory for CD4+ and CD8+ T cells, respectively. The main results of the present study are that treatment of β-Thalassemia patients with Sirolimus has a positive impact on the biological activity and number of memory CD4+ and CD8+ T cells releasing IFN-γ following stimulation with antigenic stimuli present in immunological memory. These data are to our knowledge novel and in our opinion of interest, in consideration of the fact that β-Thalassemia patients are considered prone to immune deficiency. 相似文献
112.
Summary The present study has been carried out to determine if glycine, an allosteric modulator of NMDA receptor, is involved in the vascular effect induced by the activation of the CNS NMDA receptors.Icv NMDA (from 0.01 to 1µg/rat in the 3rd ventricle) caused a significant increase in arterial blood pressure in conscious freely moving rats. Moreover, the hypertension was associated with behavioural modifications (jumping, rearing, teething and running). Glycine pretreatment (1 and 10µg/raticv), significantly increased the NMDA hypertension. Glycine alone did not cause any arterial blood pressure modification while it induced a slight sedation. HA-966 (an antagonist of the glycine site on NMDA receptor) administration (1–10µg/raticv 5 min before glycine) significantly antagonized the glycine effects on NMDA hypertension.Alone HA-966 neither modified arterial blood pressure nor antagonized NMDA hypertension. In conclusion, our investigations confirm NMDA receptor involvement in cardiovascular function and they demonstrate thatin vivo glycine positively modulates NMDA receptors. 相似文献
113.
An anaerobic granular sludge was enriched to utilize H2/CO2 in a continuous gas-fed up-flow anaerobic sludge reactor by applying operating conditions expected to produce acetic acid, butyric acid, and ethanol. Three stages of fermentation were found: Stage I with acetic acid accumulation with the highest concentration of 35 mM along with a pH decrease from initial 6 to 4.5. In Stage II, H2/CO2 was replaced by 100% H2 to induce solventogenesis, whereas butyric acid was produced with the highest concentration of 2.5 mM. At stage III with 10 µM tungsten (W) addition, iso-valeric acid, valeric acid, and caproic acid were produced at pH 4.5–5.0. In the batch tests inoculated with the enriched sludge taken from the bioreactor (day 70), however, methane production occurred at pH 6. Exogenous 15 mM acetate addition enhanced both the H2 and CO2 consumption rate compared to exogenous 10, 30, and 45 mM acetate by the enriched sludge. Exogenous acetate was failed to be converted to ethanol using H2 as electron donor by the enriched acetogens. 相似文献
114.
Leirla Salazar Hafida Fsihi Edda de Rossi Giovanna Riccardi Carmen Rios Stewart T. Cole Howard E. Takiff 《Molecular microbiology》1996,20(2):283-293
The genus Mycobacterium is composed of species with widely differing growth rates ranging from approximately three hours in Mycobacterium smegmatis to two weeks in Mycobacterium leprae. As DNA replication is coupled to cell duplication, it may be regulated by common mechanisms. The chromosomal regions surrounding the origins of DNA replication from M. smegmatis, M. tuberculosis, and M. leprae have been sequenced, and show very few differences. The gene order, rnpA-rpmH-dnaA-dnaN-recF-orf-gyrB-gyrA, is the same as in other Gram-positive organisms. Although the general organization in M. smegmatis is very similar to that of Streptomyces spp., a closely related genus, M. tuberculosis and M. leprae differ as they lack an open reading frame, between dnaN and recF, which is similar to the gnd gene of Escherichia coli. Within the three mycobacterial species, there is extensive sequence conservation in the intergenic regions flanking dnaA, but more variation from the consensus DnaA box sequence was seen than in other bacteria. By means of subcloning experiments, the putative chromosomal origin of replication of M. smegmatis, containing the dnaA-dnaN region, was shown to promote autonomous replication in M. smegmatis, unlike the corresponding regions from M. tuberculosis or M. leprae. 相似文献
115.
Two independent pathways of expression lead to self-assembly of the rabbit hemorrhagic disease virus capsid protein. 总被引:4,自引:1,他引:3 下载免费PDF全文
The rabbit hemorrhagic disease virus capsid protein was expressed in insect cells either as an individual protein species, from a mRNA analogous to the viral subgenomic RNA, or as part of a polyprotein that included the viral 3C-like protease and the RNA polymerase. Both pathways of expression led to the assembly of viruslike particles morphologically and antigenically similar to purified virus. 相似文献
116.
We investigated patterns of resource partitioning between two brackish crustaceans (I. baltica and G. insensibilis) on trophic mosaics of fungal species colonizing vegetal detritus. Laboratory feeding experiments were carried out to assess consumption rates and diet selection of single individuals belonging to five populations. Adults of two co-occurring population of both G. insensibilis and I. baltica and one population of G. insensibilis, occurring alone in another habitat patch, were studied. Each individual were offered both fragments of Cymodocea nodosa conditioned by 8 fungal species and sterilized fragments as sole food source for 7 days. Both species preferred "conditioned" detritus but potential resource use was greater in G. insensibilis than in I. baltica. Individual niche breadth increased and phenotypic variability reduced in the allotopic sample. Trophic similarities were lower between individuals of co-occuring populations than between I. baltica and the allotopic G. insensibilis. The results suggest that co-occurrence is an important factor contributing to the enhancement of phenotypic variability and, consequently, to a trophic generalization at population level in G. insensibilis. It emphasizes the role of fungal patchiness on detritus in regulating resource partitioning between the two species. 相似文献
117.
Laura Chiarantini Luigia Rossi Alessandra Fraternale Mauro Magnani 《Molecular and cellular biochemistry》1995,144(1):53-59
Human and murine blood cells treated with ZnCl2 and bis(sulfosuccinimidyl)suberate (BS3) (a cross linking agent) undergo band 3 clustering and binding of hemoglobin to red blood cell membrane proteins. These clusters induce autologous IgG binding and complement fixation, thus favouring the phagocytosis of ZnCl2/BS3 treated cells by macrophages. The extension of red blood cell opsonization can be easily modulated by changing the ZnCl2 concentration in the 0.1–1.0 mM range thus providing an effective way to affect blood cell recognition by macrophages. In fact, murine erythrocytes treated with increasing ZnCl2 concentrations have proportionally reduced survivals when reinjected into the animal. Furthermore, the organ sequestration of ZnCl2/BS3 treated cells strongly resembles the typical distribution of the senescent cells. Since the ZnCl2/BS3 treatment can also be performed on red blood cells loaded with drugs or other substances, this procedure is an effective drug-targeting system to be used for the delivery of molecules to peritoneal, liver and spleen macrophages. 相似文献
118.
E. Baldini Osvaldo Facini Fabrizio Nerozzi Federica Rossi Annalisa Rotondi 《Trees - Structure and Function》1997,12(2):73-81
Light partition has been examined and evaluated on five woody species (Olea europaea, Ficus carica, Pittosporum tobira, Hedera helix maculata, Persica vulgaris) in relation to their leaf morpho-histological characteristics, water and chlorophyll contents. Leaf parameters and optical
properties (reflectance, transmittance, absorbance) in PAR, FR and NIR wavebands (400–1100 nm) were preliminarily submitted
to a canonical correlation analysis where lamina thickness and water content showed a leading role in determining all the
optical properties, while chlorophyll, influential in the PAR region, was remarkably effective only in an extreme pigment
situation when green and albino patches of ivy leaves were compared. Transmittance appeared inversely related to lamina thickness
in accordance with the Lambert Beer law. Significant correlations were found also between mesophyll water content and both
transmittance (positive) and reflectance (negative). Olive leaves showed peculiar optical patterns because of the dense and
continuous trichome layer on their abaxial surface.
Received: 3 January 1997 / Accepted: 5 May 1997 相似文献
119.
Amicucci Antonella Rossi Ismaela Potenza Lucia Agostini Deborah Stocchi Vilberto 《Biotechnology Techniques》1997,11(3):149-154
Isolates of white truffles were identified as Tuber magnatum Pico species using a pair of primers selected from a sequence characterised amplified region (SCAR) and a specific random amplified polymorphic DNA (RAPD) marker. The present study reveals that PCR-fragment-pattern polymorphisms, the construction of probes and couples of primers from one or more of these polymorphic fragments may provide a useful and rapid tool for identifying species of ectomycorrhizal fungi in addition to conventional methods (morphological parameters). 相似文献
120.
Thedei G. Nozawa S.R. Simoes A.L. Rossi A. 《World journal of microbiology & biotechnology》1997,13(6):609-611
The mycelial Pi-repressible alkaline phosphatase of the wild-type strain 74A of Neurospora crassa was separated into at least ten isoforms by isoelectric focusing. The components visualized by activity with sodium -naphthyl phosphate as the substrate were predominantly acidic proteins with isoelectric points ranging from pH 4.5 to 7.6. The number of these isoforms was a function of growth pH. Strain pho-2A did not produce active Pi-repressible alkaline phosphatase (the pho-2 gene codes for its amino acid sequence), which gives an indication that these isoforms are encoded by the same structural gene. 相似文献