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71.
Gavallo F Di Carlo E Quaglin E Jezzi M Strasly M Bussolino F Colombo MP Nanni P Lollini PL Musiani P Forni G 《Journal of biological regulators and homeostatic agents》2001,15(4):351-358
As a natural consequence of the expression of the activated transforming rat Her-2/neu oncogene all mammary glands of female transgenic BALB/c (BALB-neuT) mice develop atypical epithelial hyperplasia which progresses to invasive carcinoma. A lobular carcinoma is palpable in all mammary glands of 33-week-old BALB-neuT mice. This progression is markedly delayed by systemic administration of IL-12. In a series of studies the best administration schedule, the lowest dose and the most effective administration time have been defined. The cellular and molecular mechanisms resulting in the delay of carcinogenesis have been established. By means of a series of downstream mediators IL-12 inhibits the angiogenic burst that goes along with the passage from preneoplastic to neoplastic and invasive lesions; it also recruits lymphoid cells in the mammary pad and activates their cytotoxicity towards neoplastic cells and newly formed vessels; and furthermore, it induces lymphoid cells to trigger antiangiogenic activities in neoplastic epithelial cells. Effective, low-dose and non-toxic IL-12 treatments may thus be envisaged as a possible option in the management of preneoplastic mammary lesions and in mammary cancer prevention. 相似文献
72.
Sfondrini L Besusso D Zoia MT Rodolfo M Invernizzi AM Taniguchi M Nakayama T Colombo MP Ménard S Balsari A 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(1):151-158
The role of NKT cells on antitumor activity of CpG oligodeoxynucleotides (ODNs) was evaluated by peritumoral injections of CpG-ODNs in s.c. melanoma-bearing mice of strains differing in the number of NKT cells (athymic nude mice, recombination-activating gene(-/-)/transgenic V(alpha)14/Vbeta8.2 mice that generate NKT cells; J(alpha)281(-/-) mice and CD1(-/-) mice, which both have a strongly reduced number of NKT cells; and C57BL/6 wild-type mice). Tumor growth was significantly inhibited in strains enriched or depleted of NKT cells. The two murine strains having a reduced number of NKT cells differed significantly in the CpG-dependent tumor growth inhibition: in J(alpha)281(-/-) mice this inhibition was superimposable to that observed in C57BL/6 mice, while in CD1(-/-) mice the inhibition was dramatic. The increased tumor inhibition in CD1(-/-) correlated with a significantly higher ratio of IFN-gamma-IL-4 production in response to CpG as compared with C57BL/6 and J(alpha)281(-/-) mice. Experiments in which preparations of APCs and lymphocytes of the three strains were mixed showed that in the presence of APCs not expressing CD1, the production of CpG-ODN-induced type 1 cytokines was higher. Phenotype analysis of IFN-gamma- and IL-4-producing cells revealed that the differences between CD1(-/-) and C57BL/6 in the production of these two cytokines were mainly due to CD3(+) T lymphocytes. These data point to a regulatory role for the CD1 molecule in antitumor activity induced by danger signals, independently of V(alpha)14 NKT cells. The identification of a CD1-dependent suppressive subpopulation(s) might have important implications for the study of tolerance in the context of cancer, autoimmunity, and transplantation. 相似文献
73.
Development of Genus/Species-Specific PCR Analysis for Identification of <Emphasis Type="Italic">Carnobacterium</Emphasis> Strains 总被引:6,自引:0,他引:6
Heterofermentative lactic acid bacteria belonging to the genus Carnobacterium are currently divided into seven different species, C. piscicola, C. mobile, C. gallinarum, C. inhibens, C. divergens, C. funditum, and C. alterfunditum. 16S rDNA-targeted PCR assay was carried out for the identification of the genus Carnobacterium. In addition, type strains of all Carnobacterium species were analyzed by 16S–23S rDNA intergenic spacer analysis in comparison with type strains of phylogenetically related
lactic acid bacteria. These methods enabled the identification and the discrimination among Carnobacterium species and the other phylogenetically related lactic acid bacteria. Likewise, analogous results were obtained by restriction
analysis of amplified 16S rDNA performed with HaeIII and HinfI as restriction enzymes.
Received: 25 July 2001 / Accepted: 19 October 2001 相似文献
74.
Thrombin is a primary target for the development of novel anticoagulants, since it plays two important and opposite roles in hemostasis: procoagulant and anticoagulant. All thrombin functions are influenced by Na+ binding, which triggers the transition of this enzyme from an anticoagulant (slow) form to a procoagulant (fast) form. In previous studies, we have conveniently produced by chemical synthesis analogues of the N-terminal fragment 1-47 of hirudin HM2 containing noncoded amino acids and displaying up to approximately 2700-fold more potent antithrombin activity, comparable to that of full-length hirudin. In the work presented here, we have exploited the versatility of chemical synthesis to probe the structural and energetic properties of the S3 site of thrombin through perturbations introduced in the structure of hirudin fragment 1-47. In particular, we have investigated the effects of systematic replacement of Tyr3 with noncoded amino acids retaining the aromatic nucleus of Tyr, as well as similar hydrophobic and steric properties, but possessing different electronic (e.g., p-fluoro-, p-iodo-, or p-nitro-Phe), charge (p-aminomethyl-Phe), or conformational (homo-Phe) properties. Our results indicate that the affinity of fragment 1-47 for thrombin is proportional to the desolvation free energy change upon complex formation, and is inversely related to the electric dipole moment of the amino acid side chain at position 3 of hirudin. In this study, we have also identified the key features that are responsible for the preferential binding of hirudin to the procoagulant (fast) form of thrombin. Strikingly, shaving at position 3, by Tyr --> Ala exchange, abolishes the differences in the affinity for thrombin allosteric forms, whereas a bulkier side chain (e.g., beta-naphthylalanine) improves binding preferentially to the fast form. These results provide strong, albeit indirect, evidence that the procoagulant (fast) form of thrombin is in a more open and accessible conformation with respect to the less forgiving structure it acquires in the slow form. This view is also supported by the results of molecular dynamics simulations conducted for 18 ns on free thrombin in full explicit water, showing that after approximately 5 ns thrombin undergoes a significant conformational transition, from a more open conformation (which we propose can be related to the fast form) to a more compact and closed one (which we propose can be related to the slow form). This transition mainly involves the Trp148 and Trp60D loop, the S3 site, and the fibrinogen binding site, whereas the S1 site, the Na+-binding site, and the catalytic pocket remain essentially unchanged. In particular, our data indicate that the S3 site of the enzyme is less accessible to water in the putative slow form. This structural picture provides a reasonable molecular explanation for the fact that physiological substrates related to the procoagulant activity of thrombin (fibrinogen, thrombin receptor 1, and factor XIII) orient a bulky side chain into the S3 site of the enzyme. Taken together, our results can have important implications for the design of novel thrombin inhibitors, of practical utility in the treatment of coagulative disorders. 相似文献
75.
MADS-box protein complexes control carpel and ovule development in Arabidopsis 总被引:28,自引:0,他引:28
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Favaro R Pinyopich A Battaglia R Kooiker M Borghi L Ditta G Yanofsky MF Kater MM Colombo L 《The Plant cell》2003,15(11):2603-2611
The AGAMOUS (AG) gene is necessary for stamen and carpel development and is part of a monophyletic clade of MADS-box genes that also includes SHATTERPROOF1 (SHP1), SHP2, and SEEDSTICK (STK). Here, we show that ectopic expression of either the STK or SHP gene is sufficient to induce the transformation of sepals into carpeloid organs bearing ovules. Moreover, the fact that these organ transformations occur when the STK gene is expressed ectopically in ag mutants shows that STK can promote carpel development in the absence of AG activity. We also show that STK, AG, SHP1, and SHP2 can form multimeric complexes and that these interactions require the SEPALLATA (SEP) MADS-box proteins. We provide genetic evidence for this role of the SEP proteins by showing that a reduction in SEP activity leads to the loss of normal ovule development, similar to what occurs in stk shp1 shp2 triple mutants. Together, these results indicate that the SEP proteins, which are known to form multimeric complexes in the control of flower organ identity, also form complexes to control normal ovule development. 相似文献
76.
Molecular and phylogenetic analyses of the complete MADS-box transcription factor family in Arabidopsis: new openings to the MADS world 总被引:25,自引:0,他引:25
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Parenicová L de Folter S Kieffer M Horner DS Favalli C Busscher J Cook HE Ingram RM Kater MM Davies B Angenent GC Colombo L 《The Plant cell》2003,15(7):1538-1551
77.
78.
Venturoli S Paradisi R Bagnoli A Colombo FM Ravaioli B Vianello F Mancini F Gualerzi B Porcu E Seracchioli R 《Hormone research》2001,56(1-2):25-31
OBJECTIVE: To evaluate the safety and efficacy of a low dose of flutamide (125 mg/day) in maintaining the clinical results already obtained using a higher dose (250 mg/day), in women suffering from hirsutism. METHOD: Forty-three women suffering from hirsutism of varying origin received 250 mg/day of flutamide as an initial treatment for 12 months and, subsequently, 125 mg/day of flutamide for an additional 12 months as a maintenance treatment. Hirsutism was evaluated by the Ferriman-Gallwey score, and hair diameter and hair growth rate were determined by a special image analysis processor. Biochemical, clinical and hormonal parameters were evaluated in basal conditions and every 2-6 months. RESULTS: The significant decrease in the hirsutism score, hair diameter and hair growth rate during the initial treatment period was confirmed at the end of the maintenance treatment period. Androgen levels decreased up to the end of the initial treatment period and partially decreased during the maintenance treatment. During the initial treatment period, 4 subjects showed an increase of aspartate aminotransferase and alanine aminotransferase and dropped out. During the maintenance treatment period, no side effects or complications were observed. CONCLUSION: Satisfactory management of hirsutism with flutamide seems to be represented by an initial treatment period using 250 mg/day to achieve satisfactory results, followed by a long maintenance treatment period using 125 mg/day. 相似文献
79.
Susceptibility profile of vaginal yeast isolates from Brazil 总被引:3,自引:0,他引:3
Vaginal specimens for culture were obtained from two hundred and five immunocompetent, non-hospitalized patients selected among all women attending the Gynecology and Obstetric Ambulatory Clinic of the University of Espírito Santo, Brazil, during a 2-year period (From 1998 to 1999). Patients were checked for signs and symptoms of vulvovaginitis and previous use of topical and systemic antifungal drugs. Yeast isolates were identified by classical methods and the antifungal susceptibility profile was determined according to NCCLS microbroth assay. The prevalence of vaginal yeast isolates from asymptomatic women was 25% (30/121) and 60% (50/84) among patients with symptoms of vulvovaginitis. Candida albicans was the most frequently isolated species in both groups (46% and 90%, respectively), followed by C. glabrata (13% and 6%, respectively). All isolates were susceptible to amphotericin B. Only ten isolates had dose dependent susceptibility (DDS) or resistance to azoles; and seven of these were non-albicans species. Based on our results we suggest that species identification and antifungal susceptibility testing need not be routinely performed in immunocompetent women, and may be reasonable only for the minority of patients with complicated vulvovaginal candidiasis that fail to respond to therapy. 相似文献
80.
Boland JL Corbeij HA Van Der Giessen W Seabra-Gomes R Suryapranata H Wijns W Hanet C Suttorp MJ Buller C Bonnier JJ Colombo A Van Birgelen C Pieper M Mangioni JA Londero H Carere RG Hamm CW Bonan R Bartorelli A Kyriakides ZS Chauhan A Rothman M Grinfeld L Oosterwijk C Serruys PW Cumberland DC 《International journal of cardiovascular interventions》2000,3(4):215-225
AIMS: The BiodivYsio trade mark stent (Biocompatibles Ltd, Farnham, UK) is coated with a phosphorylcholine (PC)-containing copolymer to confer biocompatibility. The SOPHOS (Study Of PHosphorylcholine coating On Stents) study was designed to assess the safety and efficacy of this novel coronary stent and by indirect comparison to indicate equivalence with other formal stent studies. METHODS AND RESULTS: Patients with angina and a single short (#x2A7F;12 mm) de novo lesion in a native coronary artery of >/=2.75 mm diameter were included. A total of 425 patients were allocated in 24 centers. Clinical data were collected at one-, six- and nine-month follow-up. Angiography was performed before and after the stent implantation. In addition, in the first 200 patients (SOPHOS A) angiography was routinely performed at six months. The following 225 patients (SOPHOS B) were merely followed up clinically. The primary end-point of the study, the six-month MACE-rate (MACE = Major Adverse Cardiac Events) was 13.4% (two cardiac death; five Q-wave/nine non-Q-wave myocardial infarctions (MI); nine CABG and 32 target lesion revascularization (TLR), which is similar to the calculated 15% MACE-rate in comparable reference studies. Secondary end-points included among others restenosis at six months in the SOPHOS A population. The target vessel diameter was 2.98 +/- 0.48 mm. Minimal lumen diameter pre/post procedure and at follow-up was 1.00 +/- 0.32, 2.69 +/- 0.37, 1.91 +/- 0.71 mm, respectively. The binary restenosis rate (>/=50% diameter stenosis at follow-up) was 17.7%. CONCLUSION: The coronary BiodivYsio stent is safe and effective as a primary device for the treatment of native coronary artery lesions in patients with stable or unstable angina pectoris. Clinical and angiographic results are in the statistical range of equivalence with comparable studies with other current stents. 相似文献