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1.
M N Lorenzo R Y Khan Y Wang S C Tai G C Chan A H Cheung P A Marsden 《Biochimica et biophysica acta》2001,1522(1):46-52
Generation of the functionally pleiotropic members of the endothelin vasoactive peptide family is critically catalyzed by unique type II metalloproteases, termed endothelin converting enzymes (ECE). Isolation of human ECE-2 (EC 3.4.24.71) cDNAs revealed deduced open reading frames of 787 and 765 amino acids with approximately 60% identity with human ECE-1. Characterization of mRNA variants revealed mRNA structural diversity at the 5'-terminus. Two mRNA species exist containing distinct first and second exons. Furthermore, in one of these species, an in-frame deletion of the intracytoplasmic domain removed 29 amino acids. Because of the previously reported human genetic diseases ascribed to germline mutations of member genes of the endothelin family, ECE2 was localized in human chromosomes with fluorescence in situ hybridization and radiation hybrid mapping to 3q28-q29 and SHGC-20171/D3S1571, respectively. 相似文献
2.
Lorenzo Dal Bo Paolo Mazzucchelli Antonio Marzo 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2000,749(2):258
Zofenopril is a pro-drug designed to undergo metabolic hydrolysis yielding the active free sulfhydryl compound zofenoprilat, which is an angiotensin converting enzyme (ACE) inhibitor, endowed also with a marked cardioprotective activity. A simple, highly sensitive specific LC–MS–MS method was developed for the determination of zofenopril and zofenoprilat in human plasma. In order to prevent oxidative degradation of zofenoprilat and its internal standard, their free sulfhydryl groups were protected by treatment with N-ethylmaleimide (NEM), which produced the succinimide derivatives. The compounds and their corresponding fluorine derivatives, used as internal standards, were extracted from plasma with toluene. The reconstituted dried extracts were chromatographed and then monitored by a triple-stage-quadrupole instrument operating in the negative ion spray ionization mode. The method was validated over the concentration range of 1–300 ng/ml for zofenopril and 2–600 ng/ml for zofenoprilat. Inter- and intra-assay precision and accuracy of both zofenopril and zofenoprilat were better than 10%. The limit of quantitation was 1 ng/ml with zofenopril and 2 ng/ml with zofenoprilat. Extraction recovery proved to be on average 84.8% with zofenopril and 70.1% with zofenoprilat. Similar recoveries were shown by the above two internal standards. The method was applied to measure plasma concentrations of zofenopril and zofenoprilat in 18 healthy volunteers treated orally with zofenopril calcium salt at the dose of 60 mg. 相似文献
3.
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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5.
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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7.
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
8.
D Di Lorenzo G Ruggeri C Iacobello S Belloli M Gion D T Zava S Ghielmi A Albertini 《The International journal of biological markers》1991,6(3):151-158
A radioreceptor assay (RRA) for the determination of total estrogen activity, was set up and used to assess the possible presence of exogenous molecules with estrogen activity in serum; a comparison was made with the specific radioimmunoassay (RIA) for the endogenous estrogen 17-B estradiol (17-B-E2). The assay was first performed on sera from healthy people taking estrogens in the form of oral contraceptives or lotions for local application whose total estrogenic activity in the blood was assumed to be abnormal. The assay was then performed on serum from 98 patients with early breast cancer and 20 patients with metastasis, not undergoing hormone therapy. A higher estrogen activity was found in 2.5% of sera compared to the activity found using the RIA method which is specific for endogenous estrogen 17-B-E2, the RRA/17-B-E2 ratio being higher than 3. Increased estrogen activity was found in 10% serum samples from digoxin treated cardiopathic patients, with an RRA/17-B-E2 ratio ranging from 4.4 to 20. The RRA assay could prove useful for showing up exogenous estrogen activity from various sources (drugs, food) in sera of people in whom estrogen stimulation could be potentially dangerous (i.e. in patients with hormone-sensitive tumors). This exogenous activity could support a certain degree of neoplastic stimulation and, therefore, unfavourably condition the patients' therapeutic response. 相似文献
9.
Sara Basconsuelo Herminda Reinoso Eugenia Lorenzo Rubén Bottini 《Plant Growth Regulation》1995,16(2):113-119
Morphological studies were carried out with peach flower buds collected monthly in 1989 and 1990, from two months before leaf fall (7 March) until two to three weeks before bloom (7/8 August). Chilled (2–4°C for 30 days) and unchilled buds were exposed to 20 to 25°C, 100% RH and continuous light. Gibberellin A3 (3 ng or 30 ng) was applied to some of the non-chilled cuttings at three days intervals. Then, 12, 19, and 26 days after they were planted, the buds were sampled and processed for histological studies. Cultured flower buds (chilled or unchilled) had accelerated anther and gynoecium morphogenesis after 12 days under controlled conditions, compared to buds processed immediately after collection from the field. Chilling treatment augmented the bud culture effect, while Gibberellin A3 applications to the excised buds retarded bud morphogenesis to a stage comparable to that of buds collected directly from the field. This, suggests that the comparatively high levels of Gibberellin A1/3 we previously found in mid winter [15, 18] could be at least one of the factors that controls floral bud dormancy by retarding anther and gynoecium development. 相似文献
10.
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