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981.
982.
Emilia Mellado Rafael De La Camara Buenaventura Buendía Juan L. Rodriguez-Tudela Manuel Cuenca-Estrella 《Revista iberoamericana de micología》2013,30(1):64-68
BackgroundAn allogeneic hematopoietic cell transplantation (allo-HCT) patient presented with chronic pulmonary aspergillosis associated to pulmonary graft versus host disease (GVHD) and was treated for a long time with several antifungal agents that were administered as prophylaxis, combination therapies, and maintenance treatment. The patient suffered from a breakthrough invasive pulmonary aspergillosis due to Aspergillus fumigatus after long-term antifungal therapy.Material and methodsSeveral isolates were analyzed. First isolates were susceptible in vitro to all azole agents. However, after prolonged treatment with itraconazole and voriconazole a multiple azole resistant A. fumigatus isolate was cultured from bronchoalveolar lavage (BAL) when the patient was suffering from an invasive infection, and cavitary lesions were observed.ResultsAnalysis of the resistant mechanisms operating in the last strain led us to report the first isolation in Spain of an azole resistant A. fumigatus strain harboring the L98H mutation in combination with the tandem repeat (TR) alteration in CYP51A gene (TR-L98H). Long-term azole therapy may increase the risk of resistance selecting strains exhibiting reduced susceptibility to these compounds. However, since the isolates were genetically different the suggestion that could be made is that the resistance was not induced during the prolonged azole therapy but the patient might simply have acquired this resistant isolate from the environment, selected by the therapy.ConclusionsThese findings suggest that in all long-term treatments with antifungal agents, especially with azoles, repeated sampling and regular susceptibility testing of strains isolated is necessary as resistant isolates could be selected. 相似文献
983.
Paecilomyces lilacinus is a geographically widespread nematophagous fungus and a promising biological control agent against plant parasitic nematodes. However, relatively little is known about its patterns of genetic variation through its broad geographic and ecological contexts. In this study, we analyzed the genetic variation of 2 virulence-associated genes (PLS and PLC) and 4 housekeeping gene fragments (ITS, RPB1, RPB2, and β-tubulin) among 80 P. lilacinus specimens collected from 7 locations in China. Various degrees of polymorphism and haplotype diversity were observed among the six gene fragments. However, no genetic differentiation was observed among the geographic populations, consistent with extensive gene flow among these geographic populations of P. lilacinus in China. Our analysis also suggested that clonal reproduction was the predominant mode of reproduction in natural populations of P. lilacinus. 相似文献
984.
985.
José Correa-Basurto Judith Espinosa-Raya Mario González-May L. Michel Espinoza-Fonseca Iván Vázquez-Alcántara José Trujillo-Ferrara 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):133-138
Two arylderivatives, 3a-Acetoxy-5H-pyrrolo(1,2-a) (3,1)benzoxazin-1,5-(3aH)-dione 3 and cis-N-p-Acetoxy-phenylisomaleimide 4, were synthesized from anthranilic acid and para-aminophenol, respectively. The inhibitory effects of these compounds on acetylcholinesterase (AChE) activity were evaluated in vitro as well as by docking simulations. Both compounds showed inhibition of AChE activity (Ki = 4.72 ± 2.3 μM for 3 and 3.6 ± 1.8 μM for 4) in in vitro studies. Moreover, they behaved as irreversible inhibitors and made π–π interaction with W84 and hydrogen bonded with S200 and Y337 according to experimental data and docking calculations. The docking calculations showed ΔG bind (kcal/mol) of ? 9.22 for 3 and ? 8.58 for 4. These two compounds that can be use as leads for a new family of anti-Alzheimer disease drugs. 相似文献
986.
For a long time, Cercosaura ocellata was considered polytypic, with three subspecies: C. ocellata ocellata, C. ocellata petersi and C. ocellata bassleri. Recently, C. ocellata bassleri was elevated to full species, based on analysis of a few molecular samples from Peru. This species complex is widely distributed in South America, occurring in Amazonia, Cerrado, Atlantic forest and Pampa biomes. The monophyly and species diversity of C. ocellata are still unstudied. Here, we infer phylogenetic relationships and species diversity of this group analysing 2326 base pairs of three mitochondrial (12S, 16S, and ND4) and one nuclear (c-mos) genes. Our taxon sampling of 115 specimens includes 72 samples of C. ocellata and sequences of other Cercosaura species and closely related Cercosaurinae. Maximum likelihood phylogenetic analysis recovered the monophyly of Cercosaura and that of C. ocellata with strong support. Our analyses suggest that C. ocellata is a complex of cryptic species, which possibly started diversifying in Amazonia. 相似文献
987.
Muhammad Zareef Rashid Iqbal Neira Gamboa De Dominguez Juan Rodrigues Javid H. Zaidi Muhammad Arfan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):301-308
A series of new benzenesulfonamides, most of which are chiral, incorporating 1, 3, 4-oxadiazole and amino acid moieties have been synthesized. Some of these compounds were screened for antimalarial activity and also evaluated for their ability to inhibit hem polymerization. The electrophoretic analysis indicated that one compound was effective in inhibiting the degradation of hemoglobin. The synthesized compounds were tested in mice infected with Plasmodium berghei. These derivatives have the potential for the development of novel antimalarial lead compounds. 相似文献
988.
Christopher J. Fowler Gunnar Tiger María L. López-Rodríguez Alma Viso Silvia Ortega-Gutiérrez José A. Ramos 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):225-231
Arachidonoyl-serotonin inhibits in a mixed-type manner the metabolism of the endocannabinoid anandamide by the enzyme fatty acid amidohydrolase. In the present study, compounds related to arachidonoyl-serotonin have been synthesised and investigated for their ability to inhibit anandamide hydrolysis by this enzyme in rat brain homogenates. Removal of the 5-hydroxy from the serotonin head group of arachidonoyl-serotonin produced a compound (N-arachidonoyltryptamine) that was a 2.3-fold weaker inhibitor of anandamide hydrolysis, but which also produced its inhibition by a mixed-type manner (Ki(slope) 1.3 µM; Ki(intercept) 44 µM). Replacement of the amide linkage in this compound by an ester group further reduced the potency. In contrast, replacement of the arachidonoyl side chain by a linolenoyl side chain did not affect the observed potency. N-(Fur-3-ylmethyl) arachidonamide (UCM707), N-(fur-3-ylmethyl)linolenamide and N-(fur-3-ylmethyl)oleamide inhibited anandamide hydrolysis with pI50 values of 4.53, 5.36 and 5.25, respectively. The linolenamide derivative was also found to be a mixed-type inhibitor. It is concluded that the 5-hydroxy group of arachidonoyl-serotonin contributes to, but is not essential for, inhibitory potency at fatty acid amidohydrolase. 相似文献
989.
Humaira Rasheed Amanda Phipps-Green Ruth Topless Jade E Hollis-Moffatt Jennie Harré Hindmarsh Christopher Franklin Nicola Dalbeth Peter B Jones Douglas HN White Lisa K Stamp Tony R Merriman 《Arthritis research & therapy》2013,15(6):R177
Introduction
The T allele of a single nucleotide polymorphism (SNP: rs2544390) in lipoprotein receptor-related protein 2 (LRP2) is associated with higher serum urate and risk of gout in Japanese individuals. SNP rs2544390 also interacts with alcohol consumption in determining hyperuricemia in this population. We investigated the association of rs2544390 with gout, and interaction with all types of alcohol consumption in European and New Zealand (NZ) Māori and Pacific subjects, and a Māori study cohort from the East Coast region of NZ’s North Island.Methods
Rs2544390 was genotyped by Taqman®. From NZ a total of 1205 controls and 1431 gout cases clinically ascertained were used. Publicly available genotype and serum urate data were utilized from the Atherosclerosis Risk in Communities (ARIC) study and the Framingham Heart Study (FHS). Alcohol consumption data were obtained by consumption frequency questions in all study cohorts. Multivariate adjusted logistic regression was done using STATA.Results
The T allele of rs2544390 was associated with increased risk of gout in the combined Māori and Pacific Island cohort (OR = 1.20, P = 0.009), and associated with gout in the European subjects, but with a protective effect (OR = 0.79, PUnadjusted = 0.02). Alcohol consumption was positively associated with risk of gout in Māori and Pacific subjects (0.2% increased risk/g/week, P = 0.004). There was a non-additive interaction between any alcohol intake and the risk of gout in the combined Māori and Pacific cohorts (PInteraction = 0.001), where any alcohol intake was associated with a 4.18-fold increased risk in the CC genotype group (P = 6.6x10-5), compared with a 1.14-fold increased risk in the CT/TT genotype group (P = 0.40). These effects were not observed in European subjects.Conclusions
Association of the T-allele with gout risk in the Māori and Pacific subjects was consistent with this allele increasing serum urate in Japanese individuals. The non-additive interaction in the Māori and Pacific subjects showed that alcohol consumption over-rides any protective effect conferred by the CC genotype. Further exploration of the mechanism underlying this interaction should generate new understanding of the biological role of alcohol in gout, in addition to strengthening the evidence base for reduction of alcohol consumption in the management of gout. 相似文献990.
José A Gómez-Puerta Raquel Celis M Victoria Hernández Virginia Ruiz-Esquide Julio Ramírez Isabel Haro Juan D Ca?ete Raimon Sanmartí 《Arthritis research & therapy》2013,15(6):R182