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51.
Julio Parapar Enrique Martínez-Ansemil Carlos Caramelo Rut Collado Rüdiger Schmelz 《Helgoland Marine Research》2009,63(4):293-308
The species composition and relative abundance of the annelid benthic macrofauna (Polychaeta and Oligochaeta) inhabiting the
rocky intertidal zone of the ria of Ferrol (Galicia, NW Spain) were studied during field collections, from 2000 to 2002. A
total of 14,619 specimens (11,585 polychaetes belonging to 76 species and 24 families and 3,034 oligochaetes belonging to
18 species and two families) were collected from 98 quantitative samples taken from 13 sampling sites. The general spatial
distribution of the annelid fauna reflects an increase of the diversity from the inner to the outer part of the ria. The general
patterns found in the annelid composition suggest that the assemblages were dominated by oligochaetes in the inner sheltered
sampling sites and polychaetes in the outer more exposed sites. Several faunistical and taxonomical remarks on selected species
are presented. Two new species of oligochaetes are described: Coralliodrilus artabrensis sp. n. and Pirodrilus fungithecatus sp. n. (Naididae, Phallodrilinae). A new biological index, based on the oligochaete/polychaete ratio (O/P), is proposed as
tool to evaluate environmental quality and to monitor future changes in the environment. 相似文献
52.
53.
García MA Collado M Muñoz-Fontela C Matheu A Marcos-Villar L Arroyo J Esteban M Serrano M Rivas C 《The EMBO journal》2006,25(18):4284-4292
Oncogenic viruses frequently target the pathways controlled by tumor suppressor genes, suggesting an extra function for these proteins as antiviral factors. The control exerted by the tumor suppressor Arf on cellular proliferation is crucial to restrict tumor development; however, a potential contribution of Arf to prevent viral infectivity has remained unexplored. In the present study, we investigated the consequences of loss or increased expression of Arf on viral infection. Our results reveal that ARF expression is induced by interferon and after viral infection. Furthermore, we show that ARF protects against viral infection in a gene dosage-dependent manner, and that this antiviral action is mediated in part by PKR through a mechanism that involves ARF-induced release of PKR from nucleophosmin complexes. Finally, Arf-null mice were hypersensitive to viral infection compared to wild-type mice. Together, our results reveal a novel and unexpected role for the tumor suppressor ARF in viral infection surveillance. 相似文献
54.
Susana Delgado M. Carmen Collado Leonides Fernández Juan M. Rodríguez 《Current microbiology》2009,59(1):59-64
Lactational Raynaud’s syndrome may be misdiagnosed as infectious mastitis on the basis of the breast pain. The objective of
this work was to elucidate if microbiological analysis of milk may contribute to the differentiation of both conditions. Ten
lactating women clinically diagnosed by Spanish lactation consultants were included in the study. Of these, five suffered
from mastitis and the remaining five suffered from Raynaud’s syndrome. Breast milk samples were inoculated on diverse culture
media. Seventy isolates were selected and identified by 16S rDNA PCR sequencing. Parallel, PCR-DGGE and quantitative real-time
PCR were used to assess the presence of bacterial DNA in the samples. Neither bacteria nor yeasts could be detected in the
milk samples provided by the women suffering from Raynaud’s syndrome. In contrast, large numbers of bacteria were isolated
from those with infectious lactational mastitis. Globally, the levels of bacterial DNA were significantly higher in the milk
of mastitis-suffering women. Bacteriological analysis of milk can be an useful tool to facilitate the differential diagnosis
between the infectious mastitis and Raynaud’s syndrome during lactation. 相似文献
55.
Denise O. Guimarães Warley S. Borges Noemi J. Vieira Laiani F. de Oliveira Carlos H.T.P. da Silva Norberto P. Lopes Luis G. Dias Rosa Durán-Patrón Isidro G. Collado Mônica T. Pupo 《Phytochemistry》2010,71(11-12):1423-1429
Diketopiperazine (DKP) derivatives, named colletopiperazine, fusaperazine C and E as well as four known DKPs were isolated from cultures of Colletotrichum gloeosporioides, Penicillium crustosum, both endophytic fungi isolated from Viguiera robusta, and a Fusarium spp., an endophyte of Viguiera arenaria, respectively. Their structures were established on the basis of their spectroscopic data. Conformational analysis of two known DKPs showed that folded conformations were as energetically stable as the extended one. 相似文献
56.
57.
58.
Sixteen species of Copepoda were recorded in this first detailed study of Costa Rican zooplankton. Two of these species are halophile. Notes are given on some of the species and their distribution. One new species found will be described elsewhere. The Costa Rican fauna resembles in composition the fauna of other Central American and Caribbean regions. Relatively few species were recorded. This is partly due to a low intensity of sampling but also to the paucity of lentic habitats. The occurrence of two circumtropical species of Mesocyclops is interesting.
Résumé 16 espèces de Copépodes ont été inventoriées au cours d'une première étude détaillée du zooplankton dulcaquicole de Costa Rica. Deux des espèces trouvées sont halophiles. Des remarques sont faites a propos de quelques espèces et de leur répartition. Une nouvelle espèce est nouvelle — elle sera décrite par ailleurs. La fauna de Costa Rica ressemble par sa composition à celle des autres pays d'Amérique centrale et des îles caraibes. Relativement peu d'espèces sont notées. La faible intensité de l'échantillonnage mais aussi la pauvreté en habitats limniques en sont responsables. La présence de deux espèces circumtropicales de Mesocyclops est intéressante.相似文献
59.
Ysunza A Pamplona MC Molina F Chacón E Collado M 《Plastic and reconstructive surgery》1999,104(4):905-910
Sphincter pharyngoplasty is a surgical procedure for managing velopharyngeal insufficiency after palatal closure. This procedure is intended to create an active diaphragm for velopharyngeal closure. The purpose of this study was to evaluate velopharyngeal motion after sphincter pharyngoplasty, by using selective electromyography and simultaneous videonasopharyngoscopy. Twenty-five patients who were subjected to sphincter pharyngoplasty from 1985 to 1996 were reviewed. All conditions were evaluated by using electromyography with simultaneous videonasopharyngoscopy. The following velopharyngeal muscles were examined: superior constrictor pharyngeus, palatopharyngeus, and levator veli palatini. The palatopharyngeus was included in the superiorly based surgical flaps inserted at the posterior pharyngeal wall. Twenty-three patients (92 percent) showed complete velopharyngeal closure. The two patients with residual velopharyngeal insufficiency showed a defect size of 20 and 25 percent. None of the patients showed electromyographic activity at the superiorly based flaps, indicating absence of activity of the palatopharyngeus muscles. However, all patients showed normal electromyographic activity at the superior constrictor pharyngeus and the levator veli palatini. Videonasopharyngoscopy demonstrated that lateral pharyngeal wall movements, which ranged from 25 to 40 percent, were related to strong electromyographic activity at the superior constrictor pharyngeus. It is concluded that the superiorly based pharyngeal flaps of the sphincter pharyngoplasty do not seem to create an active diaphragm for velopharyngeal closure. Moreover, the observed sphinctering seems to be passive, caused by the contraction of the superior constrictor pharyngeus. 相似文献
60.
Isolation, structure, and HIV-1-integrase inhibitory activity of structurally diverse fungal metabolites 总被引:1,自引:0,他引:1
Singh SB Jayasuriya H Dewey R Polishook JD Dombrowski AW Zink DL Guan Z Collado J Platas G Pelaez F Felock PJ Hazuda DJ 《Journal of industrial microbiology & biotechnology》2003,30(12):721-731
HIV-1 integrase is a critical enzyme for replication of HIV, and its inhibition is one of the most promising new drug strategies for anti-retroviral therapy, with potentially significant advantages over existing therapies. In this report, a series of HIV-1 inhibitors isolated from the organic extract of fermentations from terrestrial fungi is described. These fungal species, belonging to a variety of genera, were collected from throughout the world following the strict guidelines of Rio Convention on Biodiversity. The polyketide- and terpenoid-derived inhibitors are represented by two naphthoquinones, a biphenyl and two triphenyls, a benzophenone, four aromatics with or without catechol units, a linear aliphatic terpenoid, a diterpenoid, and a sesterterpenoid. These compounds inhibited the coupled and strand-transfer reaction of HIV-1 integrase with an IC50 value of 0.5–120 µM. The bioassay-directed isolation, structure elucidation, and HIV-1 inhibitory activity of these compounds are described.Abbreviations
CH
3
CN
Acetonitrile
-
TFA
Trifluoroacetic acid
-
CD
3
CN
Deuterio acetonitrile
-
CD
2
Cl
2
Deuterio methylene chloride
-
MEK
Methyl ethyl ketone
-
ZnSe
Zinc selenide
-
UV
Ultraviolet
-
IR
Infrared
-
NMR
Nuclear magnetic resonance
-
COSY
Homonuclear H-H correlation spectroscopy
-
HMQC
Heteronuclear multiple-quantum coherence
-
HMBC
Heteronuclear multiple-bond correlation
-
EIMS
Electron-impact mass spectrometry
-
HREIMS
High-resolution electron impact mass spectrometry
-
ESIMS
Electrospray ionization mass spectrometry
-
HRFABMS
High-resolution fast atom bombardment mass spectrometry
-
MES
2-(N-morpholino)-ethane sulfonic acid 相似文献