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71.
Cuscó I Barceló MJ del Rio E Martín Y Hernández-Chico C Bussaglia E Baiget M Tizzano EF 《Human genetics》2001,108(3):222-229
Autosomal recessive spinal muscular atrophy (SMA) is classified, by age of onset and maximal motor milestones achieved, into type I (severe form), type II (intermediate form) and type III (mild/moderate form). SMA is caused by mutations in the survival motor neuron telomeric gene (SMN1) and a centromeric functional copy of this gene (SMN2) exists, both genes being located at 5q13. Homozygous deletion of exons 7 and 8 of SMN1 has been detected in approx 85% of Spanish SMA patients regardless of their phenotype. Nineteen cases with the sole deletion of exon 7 but not exon 8 (2 cases of type I, 13 cases of type II, four cases of type III) were further analysed for the presence of SMN2-SMN1 hybrid genes. We detected four different hybrid structures. Most of the patients were carriers of a hybrid structure: centromeric intron 6- centromeric exon 7- telomeric exon 8 (CCT), with or without neuronal apoptosis-inhibitor protein (NAIP). In two patients, a different hybrid structure, viz. telomeric intron 6- centromeric exon 7- telomeric exon 8 (TCT), was detected with or without NAIP. A phenotype-genotype correlation comparing the different structures of the hybrid alleles was delineated. Type I cases in our series are attributable to intrachromosomal deletion with a smaller number of SMN2 copies. Most cases with hybrid genes are type II occurring by a combination of a classical deletion in one chromosome and a hybrid gene in the other. Type III cases are closely associated with homozygozity or compound heterozygozity for hybrid genes resulting from two conversion events and have more copies of hybrid genes and SMN2 than type I or II cases. 相似文献
72.
The genus Jorunna is characterized by a dorsum covered withcaryophyllidia, a prostate with two sections, a penis usuallyunarmed but occasionally armed with hooks, a copulatory spine,the presence of an accessory gland and a labial cuticle smoothor armed with jaw elements. The examination of 216 non-typespecimens, 30 types, and a review of the literature show thatthere are 16 valid species of the genus Jorunna: J. tomentosa(Cuvier, 1804); J. funebris (Kelaart, 1859); J. pantherinaAngas,1864; J. rubescens (Bergh, 1876); J. labialis (Eliot, 1908);J. parva (Baba, 1938); J. spazzola (Marcus, 1955); J. hartleyi(Burn, 1958); J. alisonaeMarcus, 1976; J. lemchei (Marcus, 1976);J. evansi (Eliot, 1906); J. pardusBehrens & Henderson, 1981;J.ramicolaMiller, 1996 and J. onubensis Cervera, García-Gómez& García, 1986. In addition, two new species fromthe Eastern Pacific are described: J. osae n. sp. and J. tempisquensisn. sp. We propose two new combinations: Jorunna parva and J.evansi. New records for the genus Jorunna are provided fromItaly, Algeria, Seychelles, Madagascar, Thailand, Marshall Islands,New Caledonia, Île de la Réunion, Sudan, PapuaNew Guinea, Indonesia, Panama, Costa Rica, Bahamas, and SouthernMexico. We present the first preliminary phylogenetic analysisof this cryptobranch dorid genus, based on morphological anatomicaldata, and discuss the biogeography and evolution of severalcharacters in this group. The phylogeny supports the hypothesisthat the genus Jorunna is a monophyletic group and shows thatKentrodoris is nested within it. (Received 31 December 2004; accepted 10 January 2008) 相似文献
73.
Julio C. Rojas Yolanda Brindis Edi A. Malo Leopoldo Cruz-López 《Physiological Entomology》2004,29(4):356-362
Abstract. The influence of weight and colony origin of the queen of Solenopsis geminata (F.) (Hymenoptera: Formicidae) on worker attraction is studied under laboratory conditions. In the first experiment, worker response to individual queens of different weight from the same colony is evaluated. Heavier queens are more attractive than smaller queens to their own workers. In subsequent experiments, the colony origin effect is investigated and worker response to a pair of queens of the same weight from the same or different colonies is compared. When queens are from the same colony, workers do not show a significant preference between queens. However, when queens are from a different colony, workers are significantly more attracted to their own queen than to the foreign queen. Finally, the response of workers to queens of different weight from the same or different colonies is investigated. In both cases, workers are significantly more attracted to a heavier queen than a lighter queen, even if the lighter queen is their own queen. A putative pheromonal component (E)‐6‐(1‐pentenyl)‐2H‐2‐pyranone, is not positively correlated with queen weight. 相似文献
74.
Marcella Zollino Rosetta Lecce Marina Murdolo Daniela Orteschi Giuseppe Marangi Angelo Selicorni Alina Midro Giovanni Sorge Giuseppe Zampino Luigi Memo Domenica Battaglia Michael Petersen Effie Pandelia Yolanda Gyftodimou Francesca Faravelli Romano Tenconi Livia Garavelli Laura Mazzanti Rita Fischetto Pietro Cavalli Salvatore Savasta Laura Rodriguez Giovanni Neri 《Human genetics》2008,123(3):319-319
75.
76.
Bárbara Pérez-K?hler Francisca García-Moreno Yves Bayon Gemma Pascual Juan Manuel Bellón 《PloS one》2015,10(5)
Introduction
Presoaking meshes for hernia repair with antiseptics prior to implantation could decrease the adhesion of microorganisms to the material surface and reduce the risk of antibiotic resistances. In this work, we evaluate chlorhexidine and allicin (natural antiseptic not yet tested for these purposes) against vancomycin as antiseptics to be used in the pretreatment of a heavyweight polypropylene mesh using an in vitro model of bacterial contamination.Methods
Solutions of saline, vancomycin (40 µg/mL), allicin (1,000 µg/mL), chlorhexidine (2%-0.05%) and the combination allicin-chlorhexidine (900 µg/mL-0.05%) were analyzed with agar diffusion tests in the presence of 106 CFU Staphylococcus aureus ATCC25923. Additionally, sterile fragments of Surgipro (1 cm2) were soaked with the solutions and cultured onto contaminated agar plates for 24/48/72 h. The antimicrobial material DualMesh Plus was utilized as positive control. At every time, the inhibition zones were measured and the bacterial adhesion to the mesh surface quantified (sonication, scanning electron microscopy). Cytotoxicity of the treatments was examined (alamarBlue) using rabbit skin fibroblasts.Results
The largest zones of inhibition were created by allicin-chlorhexidine. Chlorhexidine was more effective than vancomycin, and allicin lost its effectiveness after 24 h. No bacteria adhered to the surface of the DualMesh Plus or the meshes soaked with vancomycin, chlorhexidine and allicin-chlorhexidine. On the contrary, saline and allicin allowed adherence of high loads of bacteria. Vancomycin had no toxic effects on fibroblasts, while allicin and chlorhexidine exerted high toxicity. Cytotoxicity was significantly reduced with the allicin-chlorhexidine combination.Conclusions
The use of antiseptics such as chlorhexidine, alone or combined with others like allicin, could represent an adequate prophylactic strategy to be used for hernia repair materials because soaking with these agents provides the mesh with similar antibacterial properties to those observed after soaking with vancomycin, similar to the effect of DualMesh Plus. 相似文献77.
78.
Patrick Orikiriza Becky Tibenderana Mark J. Siedner Yolanda Mueller Frederick Byarugaba Christopher C. Moore Emily E. Evans Maryline Bonnet Anne-Laure Page Joel Bazira Yap Boum II 《PloS one》2015,10(2)
BackgroundThere are limited data on region-specific drug susceptibility of tuberculosis (TB) in Uganda. We performed resistance testing on specimens collected from treatment-naive patients with pulmonary TB in Southwestern Uganda for first and second line anti-TB drugs. We sought to provide data to guide regional recommendations for empiric TB therapy.MethodsArchived isolates, obtained from patients at Mbarara Regional Referral Hospital from February 2009 to February 2013, were tested for resistance to isoniazid and rifampicin using the MTBDRplus and Xpert MTB/RIF assays. A subset of randomly selected isolates was tested for second line agents, including fluoroquinolones (FQs), aminoglycosides, cyclic peptides, and ethambutol using the MTBDRsl assay. We performed confirmatory testing for FQ resistance using repeated MTBDRsl, the Mycobacteria growth indicator tube (MGIT) assay, and sequencing of the gyrA and gyrB genes.ResultsWe tested isolates from 190 patients. The cohort had a median age of 33 years (IQR 26-43), 69% (131/190) were male, and the HIV prevalence was 42% (80/190). No isolates (0/190) were rifampicin-resistant and only 1/190 (0.5%) was isoniazid-resistant. Among 92 isolates tested for second-line drug resistance, 71 (77%) had interpretable results, of which none were resistant to aminoglycosides, cyclic peptides or ethambutol. Although 7 (10%) initially tested as resistant to FQs by the MTBDRsl assay, they were confirmed as susceptible by repeat MTBDRsl testing as well as by MGIT and gyrase gene sequencingConclusionWe found no MDR-TB and no resistance to ethambutol, FQs, or injectable anti-TB drugs in treatment naïve patients with pulmonary TB in Southwestern Uganda. Standard treatment guidelines for susceptible TB should be adequate for most patients with TB in this population. Where possible, molecular susceptibility testing methods should be routinely validated by culture methods. 相似文献
79.
80.
María álvarez-Viejo Yolanda Menéndez-Menéndez Jesús Otero-Hernández 《World journal of stem cells》2015,7(2):470-476
Mesenchymal stem cells, due to their characteristics are ideal candidates for cellular therapy. Currently, in culture these cells are defined by their adherence to plastic, specific surface antigen expression and multipotent differentiation potential. However, the in vivo identification of mesenchymal stem cells, before culture, is not so well established. Pre-culture identification markers would ensure higher purity than that obtained with selection based on adherence to plastic. Up until now, CD271 has been described as the most specific marker for the characterization andpurification of human bone marrow mesenchymal stem cells. This marker has been shown to be specifically expressed by these cells. Thus, CD271 has been proposed as a versatile marker to selectively isolated and expand multipotent mesenchymal stem cells with both immunosuppressive and lymphohematopoietic engraftment-promoting properties. This review focuses on this marker, specifically on identification of mesenchymal stem cells from different tissues. Literature revision suggests that CD271 should not be defined as a universal marker to identify mesenchymal stem cells before culture from different sources. In the case of bone marrow or adipose tissue, CD271 could be considered a quite suitable marker; however this marker seems to be inadequate for the isolation of mesenchymal stem cells from other tissues such as umbilical cord blood or wharton’s jelly among others. 相似文献