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A micropaleontologic study was carried out from samples collected along a section that crops out in the Santiago Coatepec Stream, located in the southeast of the state of Puebla, Mexico. The sedimentary sequence begins with a reddish conglomerate. Above, thick and thin layers of grey-greenish sandstones that continue in fine-grained, calcareous sandstones, and, finally, in limestones. The reddish conglomerate may represent a continental environment, and the marine transgression began with the sandstone deposit that contains a marine association of Invertebrates such as Trigonids (Myophorella sp.), and other Mollusks such as Trichites sp., Ostreids and Gastropods, Echinoderms, and Sponges as Cladocoropsis mirabilis. This sequence also provides a rich assemblage of larger Foraminifera as well as Algae, which is reported for the first time in this site. The larger agglutinated Foraminiferal assemblage is composed of Alveosepta jaccardi, Pseudocyclammina lituus, Everticyclammina virguliana, Rectocyclammina chouberti, Choffatella cf. Ch. tingitana, Mesoendothyra croatica, Nautiloculina oolithica, Freixialina planispiralis, Audienusina fourcadei, Placopsilina sp., Pseudocyclammina sp., Meandrospira sp. and Lenticulina sp. All those taxa were adapted to special paleoecological conditions, such as a continuous terrigenous input. The Algae are Marinella lugeoni, Pseudoepimastopora jurassica, Permocalculus sp., and Halimeda sp. The stratigraphic distribution of the larger benthic Foraminifera allow us to propose a Kimmeridgian age for the studied sequence. The opening of the Atlantic Ocean permitted the colonization of its margins by the larger Foraminifera during this time. The data provided by the larger Foraminifera, the Algae, and the lithology may suggest an internal platform environment of warm shallow water. This foraminiferal association is constituted by cosmopolitan species which are frequent in the Tethyan Realm. 相似文献
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Tomasz Michal Golas Anne Sikkema Jack Gros Richard M. C. Feron Ronald G. van den Berg Gerard M. van der Weerden Celestina Mariani J. J. H. M. Allefs 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(4):797-808
Initial screening of 14 Solanum dulcamara accessions enabled the identification of individuals resistant and susceptible to Phytophthora infestans. Crosses between contrasting genotypes resulted in three F2–BC1 populations segregating for resistance to late blight in a laboratory assay and under field conditions. Genetic profiling
of one of these populations using 128 AFLP primers generated three markers linked to the resistant phenotype. Blast analysis
of the sequenced markers resulted in a plausible gene position on the distal end of the long arm of chromosome 9 that could
be confirmed by CAPS markers. Thus, we describe a first resistant gene, named Rpi-dlc1, from S. dulcamara, a Solanum species native to Europe. In addition, one population was tested for broadness of resistance responses using a set of seven
additional P. infestans isolates, varying in virulence. This indicated the possible presence of additional Rpi genes. 相似文献
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Violin M Forbici F Cozzi-Lepri A Velleca R Bertoli A Riva C Giannella S Manconi PE Lazzarin A Pasquinucci S Tacconi L Carnevale G Mazzotta F Bonazzi L Montroni M Chirianni A Capobianchi M Ippolito G Moroni M Perno CF D'Arminio-Monforte A;I.CO.N.A. Study Group. Italian Cohort of Antiretroviral Naive patients 《Journal of biological regulators and homeostatic agents》2002,16(1):37-43
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Lopalco L Barassi C Pastori C Longhi R Burastero SE Tambussi G Mazzotta F Lazzarin A Clerici M Siccardi AG 《Journal of immunology (Baltimore, Md. : 1950)》2000,164(6):3426-3433
Exposure to HIV does not necessarily result in infection. Because primary HIV infection is associated with CCR5-tropic HIV variants (R5), CCR5-specific Abs in the sera of HIV-seronegative, HIV-exposed individuals (ESN) might be associated with protection against infection. We analyzed sera from ESN, their HIV-infected sexual partners (HIV+), and healthy controls (USN) searching for CCR5-specific Abs, studying whether incubation of PBMC with sera could prevent macrophage inflammatory protein 1 beta (Mip1 beta) (natural ligand of CCR5) binding to CCR5. Results showed that Mip1 beta binding to CCR5 was not modified by sera of either 40 HIV+ or 45 USN but was greatly reduced by sera of 6/48 ESN. Binding inhibition was due to Abs reactive with CCR5. The CCR5-specific Abs neutralized the infectivity of primary HIV isolates obtained from the corresponding HIV+ partners and of R5-primary HIV strains, but not that of CXCR4-tropic or amphitropic HIV strains. Immunoadsorption on CCR5-transfected, but not on CXCR4-transfected, cells removed CCR5-specific and virus-neutralizing Abs. Epitope mapping on purified CCR5-specific Abs showed that these Abs recognize a conformational epitope in the first cysteine loop of CCR5 (aa 89-102). Affinity-purified anti-CCR5-peptide neutralized the infectivity of R5 strains of HIV-1. Anti-CCR5 Abs inhibited Mip1beta-induced chemotaxis of PBMC from healthy donors. PBMC from two ESN (with anti-CCR5 Abs) were CCR5-negative and could not be stimulated by Mip1beta in chemotaxis assays. These results contribute to clarifying the phenomenon of immunologic resistance to HIV and may have implications for the development of a protective vaccine. 相似文献
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Park-Wyllie L Mazzotta P Pastuszak A Moretti ME Beique L Hunnisett L Friesen MH Jacobson S Kasapinovic S Chang D Diav-Citrin O Chitayat D Nulman I Einarson TR Koren G 《Teratology》2000,62(6):385-392
BACKGROUND: Corticosteroids are first-line drugs for the treatment of a variety of conditions in women of childbearing age. Information regarding human pregnancy outcome with corticosteroids is limited. METHODS: We collected prospectively and followed up 184 women exposed to prednisone in pregnancy and 188 pregnant women who were counseled by Motherisk for nonteratogenic exposure. The primary outcome was the rate of major birth defects. A meta-analysis of all epidemiological studies was conducted. The Mantel-Haenszel summary odds ratio was calculated for the pooled studies with 95% confidence intervals. A cumulative summary odds ratio was also calculated by combining studies in chronological order. Chi-squared for homogeneity was determined to establish the comparability of the studies. RESULTS: In our prospective study, there was no statistical difference in the rate of major anomalies between the corticosteroid-exposed and control groups. In the meta-analysis, the Mantel-Haenszel summary odds ratio for major malformations with all cohort studies was 1.45 [95% CI 0.80, 2.60] and 3.03 [95% CI 1.08, 8. 54] when Heinonen et al. ('77) was removed. This suggests a marginally increased risk of major malformations after first-trimester exposure to corticosteroids. In addition, summary odds ratio for case-control studies examining oral clefts was significant (3.35 [95% CI 1.97, 5.69]). CONCLUSIONS: Although prednisone does not represent a major teratogenic risk in humans at therapeutic doses, it does increase by an order of 3.4-fold the risk of oral cleft, which is consistent with the existing animal studies. 相似文献
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Manuela Sironi Mara Biasin Federica Gnudi Rachele Cagliani Irma Saulle Diego Forni Veronica Rainone Daria Trabattoni Micaela Garziano Francesco Mazzotta Luis Miguel Real Antonio Rivero-Juarez Antonio Caruz Sergio Lo Caputo Mario Clerici 《PloS one》2014,9(9)
The HAVCR2 gene encodes TIM-3, an immunoglobulin superfamily member expressed by exhausted CD8+ T cells during chronic viral infection. We investigated whether genetic variation at HAVCR2 modulates the susceptibility to HIV-1 acquisition; specifically we focused on a 3′ UTR variant (rs4704846, A/G) that represents a natural selection target. We genotyped rs4704846 in three independent cohorts of HIV-1 exposed seronegative (HESN) individuals with different geographic origin (Italy and Spain) and distinct route of exposure to HIV-1 (sexual and injection drug use). Matched HIV-1 positive subjects and healthy controls were also analyzed. In all case-control cohorts the minor G allele at rs4704846 was more common in HIV-1 infected individuals than in HESN, with healthy controls showing intermediate frequency. Results from the three association analyses were combined through a random effect meta-analysis, which revealed no heterogeneity among samples (Cochrane''s Q, p value = 0.89, I2 = 0) and yielded a p value of 6.8 ×10−4. The minor G allele at rs4704846 was found to increase HAVCR2 expression after in vitro HIV-1 infection. Thus, a positively selected polymorphism in the 3′ UTR, which modulates HAVCR2 expression, is associated with the susceptibility to HIV-1 infection. These data warrant further investigation into the role of TIM-3 in the prevention and treatment of HIV-1/AIDS. 相似文献
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H.-S. Lee Y.-Y. Chung Chandreyee Das B. Karunanandaa Jacques L. van Went Celestina Mariani T.-H. Kao 《Sexual plant reproduction》1997,10(6):341-350
In a previous study of the function of a pollen-expressed receptor kinase of Petunia inflata, PRK1, it was found that transgenic plants carrying an antisense-PRK1 gene were unable to transmit the transgene through either the male or, unexpectedly, the female. In this report, the nature
of this female phenotype was studied using one of the transgenic plants, ASRK-13. Electron and light microscopic examination
of the embryo sac and seed development of ASRK-13 and a wild-type plant revealed that embryo sac development of approximately
half of the ovules of ASRK-13 was abnormal. The development of the affected embryo sacs was arrested at the late stages of
megagametogenesis. The majority of the affected embryo sacs completed three rounds of mitosis normally, but failed to progress
through the maturation stages when cell expansion, nuclear migration, and differentiation take place. The remaining small
number of abnormal embryo sacs were arrested at either the four- or eight-nucleate stages. The ovules containing the defective
embryo sacs apparently failed to be fertilized, resulting in degeneration of half of the seeds produced by ASRK-13. RNA gel
blot analysis suggests that the PRK1 gene is expressed in the ovary, albeit at a much lower level than in the anther. The possibility that the antisense PRK1 gene is responsible for the abnormal embryo sac development is discussed.
Received: 25 April 1997 / Revision accepted: 25 June 1997 相似文献