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2.
Adriana Calderaro Giovanna Piccolo Chiara Gorrini Sara Montecchini Sabina Rossi Maria Cristina Medici Carlo Chezzi Georges Snounou 《PloS one》2012,7(10)
It has been proposed that ovale malaria in humans is caused by two closely related but distinct species of malaria parasites: P. ovale curtisi and P. ovale wallikeri. We have extended and optimized a Real-time PCR assay targeting the parasite’s small subunit ribosomal RNA (ssrRNA) gene to detect both these species. When the assay was applied to 31 archival blood samples from patients diagnosed with P. ovale, it was found that the infection in 20 was due to P. ovale curtisi and in the remaining 11 to P. ovale wallikeri. Thus, this assay provides a useful tool that can be applied to epidemiological investigations of the two newly recognized distinct P. ovale species, that might reveal if these species also differ in their clinical manifestation, drugs susceptibility and relapse periodicity. The results presented confirm that P. ovale wallikeri is not confined to Southeast Asia, since the majority of the patients analyzed in this study had acquired their P. ovale infection in African countries, mostly situated in West Africa. 相似文献
3.
Chiara Pavanello Alice Ossoli Arianna Strazzella Patrizia Risè Fabrizio Veglia Marie Lhomme Paolo Parini Laura Calabresi 《Journal of lipid research》2022,63(7):100232
Mutations in the LCAT gene cause familial LCAT deficiency (Online Mendelian Inheritance in Man ID: #245900), a very rare metabolic disorder. LCAT is the only enzyme able to esterify cholesterol in plasma, whereas sterol O-acyltransferases 1 and 2 are the enzymes esterifying cellular cholesterol in cells. Despite the complete lack of LCAT activity, patients with familial LCAT deficiency exhibit circulating cholesteryl esters (CEs) in apoB-containing lipoproteins. To analyze the origin of these CEs, we investigated 24 carriers of LCAT deficiency in this observational study. We found that CE plasma levels were significantly reduced and highly variable among carriers of two mutant LCAT alleles (22.5 [4.0–37.8] mg/dl) and slightly reduced in heterozygotes (218 [153–234] mg/dl). FA distribution in CE (CEFA) was evaluated in whole plasma and VLDL in a subgroup of the enrolled subjects. We found enrichment of C16:0, C18:0, and C18:1 species and a depletion in C18:2 and C20:4 species in the plasma of carriers of two mutant LCAT alleles. No changes were observed in heterozygotes. Furthermore, plasma triglyceride-FA distribution was remarkably similar between carriers of LCAT deficiency and controls. CEFA distribution in VLDL essentially recapitulated that of plasma, being mainly enriched in C16:0 and C18:1, while depleted in C18:2 and C20:4. Finally, after fat loading, chylomicrons of carriers of two mutant LCAT alleles showed CEs containing mainly saturated FAs. This study of CEFA composition in a large cohort of carriers of LCAT deficiency shows that in the absence of LCAT-derived CEs, CEs present in apoB-containing lipoproteins are derived from hepatic and intestinal sterol O-acyltransferase 2. 相似文献
4.
Chiara Tyndall Hansjo¨rg Lehnherr Ursula Sandmeier Eva Kulik & Thomas A. Bickle 《Molecular microbiology》1997,23(4):729-736
Eco R124I, Eco DXXI and Eco prrI are the known members of the type IC family of DNA restriction and modification systems. The first three are carried on large, conjugative plasmids, while Eco prrI is chromosomally encoded. The enzymes are coded by three genes, hsdR , hsdM and hsdS . Analysis of the DNA sequences upstream and downstream of the type IC hsd loci shows that all are highly homologous to each other and also to sequences present in the bacteriophage P1 genome. The upstream sequences include functional phd and doc genes, which encode an addiction system that stabilizes the P1 prophage state, and extend to and beyond pac , the site at which phage DNA packaging begins. Downstream of the hsd loci, P1 DNA sequences begin at exactly the same place for all of the systems. For Eco DXXI and Eco prrI the P1 homology extends for thousands of base pairs while for Eco R124I an IS 1 insertion and an associated deletion have removed most of the P1-homologous sequences. The significance of these results for the evolution of DNA restriction and modification systems is discussed. 相似文献
5.
Behavioural expression of D-1 receptor supersensitivity depends on previous stimulation of D-2 receptors 总被引:1,自引:0,他引:1
SKF 38393 (2 mg/kg s.c.), a reportedly selective D-1 agonist, failed to induce contralateral turning behaviour in naive rats bearing 12 days old unilateral 6-hydroxydopamine lesions. On the other hand strong contraversive turning in response to SKF 38393 was obtained if rats had been tested 2 or 7 days before with apomorphine (0.1 mg/kg s.c.) or with LY 171555 (0.2 mg/kg s.c.), a selective D-2 receptor agonist. Contraversive turning in response to SKF 38393 was blocked by a low dose (0.05 mg/kg s.c.) of the specific D-1 antagonist SCH 23390. The results indicate that the behavioural expression of D-1 receptor supersensitivity following lesion of dopaminergic neurons depends on previous exposure to a stimulation of D-2 receptors. 相似文献
6.
A cytochrome P450 called PBD-1 isolated from liver microsomes of an adult male Beagle dog treated with phenobarbital (PB) is structurally and functionally similar to members of the P450IIIA gene subfamily in rat and human liver microsomes. The sequence of the first 28 amino-terminal residues of PBD-1 is identical in 15 and 20 positions, respectively, to the P450IIIA forms P450p from rat and P450NF (and HLp) from human. Upon immunoblot analysis, anti-PBD-1 IgG recognizes PCNa (P450p) and PCNb (PB/PCN-E) from rat, P450NF from human, and two proteins in liver microsomes from both untreated and PB-treated dogs. Similarly, anti-PCNb IgG cross-reacts with PBD-1 and with at least one protein in microsomes from untreated dogs and two proteins in microsomes from PB-treated dogs. P450IIIA-form marker steroid 6 beta-hydroxylase activities increase 2.5-fold upon PB-treatment of dogs and are selectively inhibited by anti-PBD-1 IgG. NADPH-dependent triacetyloleandomycin (TAO) complex formation and erythromycin demethylase, also marker activities for P450IIIA forms from rats and humans, increase 4- and 5-fold in dog liver microsomes upon PB treatment, whereas immunochemically reactive PBD-1 is induced 3-fold. In microsomes from PB-treated dogs, 5 mg anti-PBD-1 IgG/nmol P450 inhibits greater than 75 and 50% of TAO complex formation and erythromycin demethylase activity, respectively. TAO complex formation is not inhibited by chloramphenicol, a selective inhibitor of the major PB-inducible dog liver cytochrome P450, PBD-2. These data suggest that PBD-1 or another immunochemically related form is responsible for a major portion of macrolide antibiotic metabolism by microsomes from PB-treated dogs and for steroid 6 beta-hydroxylation by microsomes from both untreated and PB-treated dogs. Major species differences were noted, however, in the apparent Km for 6 beta-hydroxylation of androstenedione by liver microsomes from untreated rats (24 microM), humans (380 microM), and untreated dogs (4700 microM). 相似文献
7.
Chiara D'Onofrio Caterina D. Pesce Tecla Fontana Fabrizio Ciprani Enzo Bonmassar Raffaele Calio 《Cancer immunology, immunotherapy : CII》1990,31(4):213-220
Summary Infection with human T-cell leukemia virus type I (HTLV-I) is associated in vitro and in vivo with a remarkable depression of cell-mediated immune functions. In the present report it is shown that early events following virus-induced suppression of the cell-mediated immune response of freshly isolated cord blood mononuclear cells (CBL) infected with HTLV-I can be partially counteracted by treatment with interferons , or (IFN). All three types of IFN exerted a protective effect on CBL cultures exposed to the virus. This resulted in: (a) a reduced number of virus-positive cells until 4 weeks of culture; (b) delay in the clonal expansion of infected cells (IFN and ); (c) increased natural killer cell activity of CBL, 1 week post-infection (p.i.), mediated by IFN; (d) increase of allospecific recognition of infecting and priming HTLV-I donor MT-2 cells by CBL in a cytotoxic-T-lymphocyte-like response, mediated by IFN and particularly by IFN; (e) phenotype distribution of CBL subpopulations, tested 4 days p.i., more similar to that of non-infected CBL cultures.In contrast, the overall CBL proliferation, that is profoundly depressed during the first week p.i., was not restored by IFN treatments, suggesting that boosting of the cell-mediated killing induced by IFN might involve the maturation of undifferentiated precursor cells rather than stimulation of their proliferation. The improvement of the efficiency of the antiviral immune response induced by treatment with IFN is likely to contribute to the clearance of virus-positive cells during the early phase of infection. This would provide experimental evidence to support an immunopharmacological approach contributing to the conversion of HTLV-I carriers from positive to negative. 相似文献
8.
Summary Photoautotrophic picoplankton is reported from some lakes located near the Italian Antarctic station of Terra Nova. Observations, carried out by both flow cytometry on water samples and electron microscopy on micro-organisms in cultures from each lake, have confirmed the occurrence in all the environments studied of this fraction accounting, in several cases, for more than the 50% of the phytoplankton, measured as chlorophyll. Cultures of the picoplankton fraction from these waters contained known prokaryotic (Synechococcus) and eukaryotic (Chlorella) genera as well as two unidentified entities, possibly prochlorophytes. 相似文献
9.
The effect of cyclosporine on PMA-stimulated superoxide production has been studied on human alveolar macrophages, human neutrophils, cytoplasts and Epstein-Barr-virus-transformed B lymphocytes. Cyclosporine inhibits superoxide production in alveolar macrophages but not in neutrophils and cytoplasts. The respiratory burst of B-lymphocytes was scarcely inhibited by cyclosporine. The activity of NADPH oxidase from macrophages and neutrophils was not directly affected by cyclosporine. These data are considered in relation with the proposed mechanism for cyclosporine action and the stimulation of the respiratory burst. 相似文献
10.
A Verrillo A de Teresa C Martino G di Chiara 《Bollettino della Società italiana di biologia sperimentale》1985,61(2):183-188
Blood glucose, insulin and prolactin concentrations were determined before and after sulpiride injection (50 mg i.m.) in 20 non-insulin-dependent diabetic patients (10 with retinopathy and 10 without evidence of retinal damage) and 10 subjects with normal glucose tolerance. Prolactin response to sulpiride was significantly higher in diabetics than in controls (at 20 min., p less than 0.01; at 30 and 60 min., p less than 0.005; at 90 min., p less than 0.01; at 120 min., p less than 0.05). The sulpiride induced hyperprolactinemia did not influence blood glucose and plasma insulin levels in controls as well as in diabetic patients. Prolactin response to sulpiride was the same in diabetics with and in those without retinal changes. We conclude that acute hyperprolactinemia seems to have no influence on glucose homeostasis in normal and non insulin-dependent diabetic subjects. 相似文献