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1.
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
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M Magnani L Chiarantini E Vittoria U Mancini L Rossi A Fazi 《Biotechnology and applied biochemistry》1992,16(2):188-194
The use of adjuvants is usually required to induce strong immunological responses to protein antigens. However, in many cases these adjuvants cannot be extensively applied in human and veterinary vaccinations because of associated inflammatory reactions or granuloma formation. We show here that protein antigens (bovine serum albumin, hog liver uricase, and yeast hexokinase), coupled to autologous red blood cells by way of a biotin-avidin-biotin bridge, elicit an immunological response in mice similar to or higher than that obtained by the use of Freund's adjuvant. Quantities as low as 0.5 micrograms/mouse are high enough to generate these immunological responses. Furthermore, splenocytes of mice immunized by red blood cell-coupled antigens can be used to generate hybridomas secreting monoclonal antibodies. Thus, the delivery of antigens by autologous red blood cells is an effective way to avoid the use of adjuvants for producing anti-peptide antibodies and possibly to generate peptide vaccines. 相似文献
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Errors Related to Different Techniques of Intraperitoneal Injection in Mice 总被引:1,自引:0,他引:1 下载免费PDF全文
We found a 12% error in the placement of intraperitoneal injections of mice with the one-man procedure of injection. With a two-man procedure, the incidence of error was consistently reduced to 1.2%. 相似文献
6.
Mohanty Madhumita Jena; Ye Maian; Li Xingli; Rossi Noreen F. 《American journal of physiology. Cell physiology》2001,281(2):C555
Hypotonicswelling increases the intracellular Ca2+ concentration([Ca2+]i) in vascular smooth muscle cells(VSMC). The source of this Ca2+ is not clear. To study thesource of increase in [Ca2+]i in response tohypotonic swelling, we measured [Ca2+]i infura 2-loaded cultured VSMC (A7r5 cells). Hypotonic swelling produced a40.7-nM increase in [Ca2+]i that was notinhibited by EGTA but was inhibited by 1 µM thapsigargin. Priordepletion of inositol 1,4,5-trisphosphate (IP3)-sensitive Ca2+ stores with vasopressin did not inhibit the increasein [Ca2+]i in response to hypotonic swelling.Exposure of 45Ca2+-loaded intracellular storesto hypotonic swelling in permeabilized VSMC produced an increase in45Ca2+ efflux, which was inhibited by 1 µMthapsigargin but not by 50 µg/ml heparin, 50 µM ruthenium red, or25 µM thio-NADP. Thus hypotonic swelling of VSMC causes a release ofCa2+ from the intracellular stores from a novel sitedistinct from the IP3-, ryanodine-, and nicotinic acidadenine dinucleotide phosphate-sensitive stores. 相似文献
7.
M Villavedra J J Battistoni S Rossi H Carol A Nieto 《International journal for parasitology》2001,31(10):1087-1092
A 30-33 kDa electroeluted fraction of T. gondii tachyzoites improved discrimination between acute and chronic phase sera when used instead of the whole tachyzoite extract in an avidity-ELISA. In order to identify the components of these fractions, crude tachyzoite antigen was fractionated by anionic exchange chromatography. The 30-33 kDa antigen cluster eluted in the not-bound fraction could account for a large proportion of the antibody response against the 30-33 kDa electroeluted fraction. According to the N-terminal sequence data, this antigen fraction is composed mainly of SAG1 and another protein with high homology to chitin binding proteins from plants. 相似文献
8.
The treatment of rats by galactosamine (2 mmol/kg i.p.), which dramatically alters the metabolism of pyrimidine nucleotides in the liver, has been used to investigate the dynamics of pyrimidine nucleotides in the rat heart. Six hours after administration of the drug, the UTP and UDPG myocardial contents were decreased by respectively 40 and 52% while the sum of uracil nucleotides was increased by 66% and that of cytosine nucleotides by 15%. When administered 5 h after galactosamine treatment, cytidine (750 nmol/rat i.v.) induced a further increase in cytosine nucleotides (46% above control value 1 h later) without however effect on uracil nucleotides. On the other hand, the administration of uridine (250 nmol/rat, i.v. 5 h after galactosamine), while restoring UTP, UDPG and the pool of uracil nucleotides, provoked a decrease in cytosine nucleotide level (-17%). In the absence of galactosamine treatment, the administration of uridine and cytidine did not induce changes in nucleotide levels despite a rise in blood cytidine concentration. All these observations support the hypothesis that: 1. the pathway for cytosine nucleotide synthesis predominant in the heart is that utilizing preformed exogenous cytidine and 2. this pathway is mainly controlled by the intracellular concentration of UTP rather than that of CTP. 相似文献
9.
Oligonucleotide probes for the detection of TEM-1 and TEM-2 beta-lactamase genes and their transposons 总被引:5,自引:0,他引:5
We describe the use of molecular probes to detect the TEM-type beta-lactamase genes. As a general probe, we prepared a 656 base pair restriction fragment, entirely within the TEM structural gene. This probe was specific for the TEM family, hybridizing only with TEM-1 and TEM-2. The TEM-1 and TEM-2 beta-lactamases differ by only one amino acid. We synthesized two oligonucleotides whose central bases correspond to this difference. The use of these oligonucleotides enables us to discriminate between TEM-1 and TEM-2 genes. Using oligonucleotides homologous to parts of Tn3, we also monitored the presence of TnA-like transposons in bacteria harboring different beta-lactamase genes. Only the TEM-1 and TEM-2 genes were found to be on transposons with terminal sequences identical to those of Tn3. All hybridization experiments were performed with both dot-blot and colony-hybridization techniques, and the suitability of these two methods for epidemiological studies is compared. 相似文献
10.
High extracellular K or Rb levels (20 mM) produce an increase in the resting EPSP and spike frequencies recorded intra cellularly from single fibres of the posterior nerve in the isolated frog labyrinth. The afferent discharge facilitation proved to be inversely related to the fibre's initial resting activity. The K effect is systematically larger than the Rb effect. High sensitive and scarcely sensitive units may be identified with respect to K and Rb action. The present findings suggest that, according to previous models of hair cell functioning, the K and Rb effects are mediated by a raise in intracellular Ca concentration which sustains an increased transmitter release at the cyto-neural junction. 相似文献