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61.
62.
Zhao-Jun Liu Pirouz Daftarian Letícia Kovalski Bo Wang Runxia Tian Diego M. Castilla Emre Dikici Victor L. Perez Sapna Deo Sylvia Daunert Omaida C. Velazquez 《PloS one》2016,11(4)
Stem cell therapy has emerged as a promising approach for treatment of a number of diseases, including delayed and non-healing wounds. However, targeted systemic delivery of therapeutic cells to the dysfunctional tissues remains one formidable challenge. Herein, we present a targeted nanocarrier-mediated cell delivery method by coating the surface of the cell to be delivered with dendrimer nanocarriers modified with adhesion molecules. Infused nanocarrier-coated cells reach to destination via recognition and association with the counterpart adhesion molecules highly or selectively expressed on the activated endothelium in diseased tissues. Once anchored on the activated endothelium, nanocarriers-coated transporting cells undergo transendothelial migration, extravasation and homing to the targeted tissues to execute their therapeutic role. We now demonstrate feasibility, efficacy and safety of our targeted nanocarrier for delivery of bone marrow cells (BMC) to cutaneous wound tissues and grafted corneas and its advantages over conventional BMC transplantation in mouse models for wound healing and neovascularization. This versatile platform is suited for targeted systemic delivery of virtually any type of therapeutic cell. 相似文献
63.
64.
S. Strobel J.A. Encarna??o N.I. Becker T.E. Trenczek 《European journal of histochemistry : EJH》2015,59(2)
Bats have a very high mass-specific energy demand due to small size and active flight. European bat species are mostly insectivorous and the morphology of the gastrointestinal (GI) tract should be adapted accordingly. This study investigated the general anatomy by histology and the function by analysing carbohydrate distribution in particular of the mucus of the GI tract of the insectivorous bat Pipistrellus pipistrellus. The GI tracts of three individuals were dissected, fixed in formaldehyde, and embedded in paraffin wax. The tissues and cells of the GI tract of P. pipistrellus were analysed by classical (acid alizarin blue, haematoxylin-eosin, and Masson Goldner Trichrome), histochemical (periodic acid-Schiff, Alcian blue at pH 2.5) and lectin histochemical (lectins WGA and HPA) staining procedures. The GI tract of P. pipistrellus is organised into the typical mammalian layers. The short, narrow, and thin-walled esophagus is simple with a folded stratified squamous epithelium without glands but mucous surface cells secreting neutral mucus. The stomach is globular shaped without specialisation. Mucous surface cells produced neutral mucus whereas neck and parietal cells secreted a mixture of neutral and acid mucus. Chief cell surface was positive for N-acetylglucosamine and the cytoplasm for N-acetylgalactosamine residues. The intestine lacked a caecum and appendix. The small intestine was divided into duodenum, jejunum-ileum and ileum-colon. The epithelium consisted of columnar enterocytes and goblet cells. The large intestine is short, only represented by the descending colon-rectum. It lacked villi and the mucosa had only crypts of Lieberkühn. Towards the colon-rectum, goblet cells produced mucus with N-acetylglucosamine residues increasing in acidity except in colon-rectum where acidity was highest in the base of crypts. Along the tube the surface of enterocytes was positive for N-acetylglucosamine and N-acetylgalactosamine. All over the mucus filling the lumen of the GI tract was positive for N-acetylglucosamine and increased in acidity in all parts except of the stomach.In conclusion, the simple GI tract showed an anatomical reduction of tissue enabling for a short retention time and a reduction of the load carried during flight: short GI tract, lack of lymphoid tissue, missing of glands in certain regions, and a distinct pattern of mucus distribution, indicating different physiological functions of these areas. The GI tract of P. pipistrellus was typical for an insectivorous species probably representing the ancestral condition.Key words: Chiroptera, esophagus, glycoconjugates, intestine, lectins, stomach 相似文献
65.
Botías C Anderson DL Meana A Garrido-Bailón E Martín-Hernández R Higes M 《Journal of invertebrate pathology》2012,110(1):108-113
Although Nosema ceranae was first isolated from the Asian honeybee (Apis cerana) in Asia and then subsequently recognized as a widespread gut parasite of the Western honeybee (Apis mellifera), its origins and primary host are yet to be accurately established. In this study we examined the possibility of an Asian origin for the parasite by looking for evidence of its ongoing spread out of Asia. To do this, we surveyed for the presence of N. ceranae in A. cerana and A. mellifera on isolated islands of the Solomon Islands (Pacific region), most of which were inhabited with A. mellifera that had been introduced from Australia and New Zealand at a time when N. ceranae was not present in either country, but on which some had also recently become inhabited with invasive A. cerana that originated from Asia with no prior history of contact with A. mellifera infected with N. ceranae. We also sought to verify previous findings that N. ceranae was widespread in Asian honeybees by surveying for its presence in isolated populations of the Asian honeybees, A. cerana, A. koschevnikovi, A. nigrocincta and A. florea. We obtained evidence that A. cerana introduced N. ceranae to A. mellifera in the Solomon Islands and also confirmed the widespread occurrence of the parasite in Asian honeybees, even reporting it for the first time in A. koschevnikovi from Borneo. Our findings provide further support for the hypothesis that N. ceranae has only recently emerged from Asia to become a parasite of A. mellifera. 相似文献
66.
VM Girijavallabhan C Alvarez F Bennett L Chen S Gavalas Y Huang SH Kim A Kosinski P Pinto R Rizvi R Rossman B Shankar L Tong F Velazquez S Venkatraman VA Verma J Kozlowski NY Shih JJ Piwinski M Maccoss CD Kwong N Bansal JL Clark AT Fowler HS Kezar J Valiyaveettil RC Reynolds JA Maddry S Ananthan JA Secrist C Li R Chase S Curry HC Huang X Tong FG Njoroge A Arasappan 《Bioorganic & medicinal chemistry letters》2012,22(17):5652-5657
Introduction of a nitrogen atom into the benzene ring of a previously identified HCV replication (replicase) benzothiazole inhibitor 1, resulted in the discovery of the more potent pyridothiazole analogues 3. The potency and PK properties of the compounds were attenuated by the introductions of various functionalities at the R(1), R(2) or R(3) positions of the molecule (compound 3). Inhibitors 38 and 44 displayed excellent potency, selectivity (GAPDH/MTS CC(50)), PK parameters in all species studied, and cross genotype activity. 相似文献
67.
Anilkumar GN Selyutin O Rosenblum SB Zeng Q Jiang Y Chan TY Pu H Wang L Bennett F Chen KX Lesburg CA Duca J Gavalas S Huang Y Pinto P Sannigrahi M Velazquez F Venkatraman S Vibulbhan B Agrawal S Ferrari E Jiang CK Huang HC Shih NY George Njoroge F Kozlowski JA 《Bioorganic & medicinal chemistry letters》2012,22(1):713-717
Development of SAR at the C2 position of indole lead 1, a palm site inhibitor of HCV NS5B polymerase (NS5B IC(50)=0.053μM, replicon EC(50)=4.8μM), is described. Initial screening identified an acyl sulfonamide moiety as an isostere for the C2 carboxylic acid group. Further SAR investigation resulted in identification of acyl sufonamide analog 7q (NS5B IC(50)=0.039μM, replicon EC(50)=0.011μM) with >100-fold improved replicon activity. 相似文献
68.
Jorge A. Encarna??o 《Journal of Ethology》2012,30(2):271-278
Sexual segregation is a common phenomenon in temperate bats, but little is known about driving forces or spatiotemporal patterns.
Sexual segregation of the tree-dwelling Daubenton’s bat (Myotis daubentonii) was analyzed. Day roosts and foraging areas of radio-tracked animals were recorded during late spring, early summer, and
late summer. Home ranges were calculated for each sex based on identified locations. Distance analysis between sex-specific
roosts and foraging areas was conducted for each period. Mixed colonies were confirmed by trapping at roosts. Home range of
males was larger (47.3 km2) than of females (9.7 km2). During late spring, distances between male and female roosts were larger (median = 715 m) than during early (median = 474 m)
and late summer (median = 489 m). Distances between sex-specific foraging areas were larger during early summer (median = 2,134 m)
than during both late spring (median = 1,116 m) and late summer (median = 628 m). The proportion of males in mixed groups
increased from late spring (0.2 ± 0.1) to late summer (0.5 ± 0.2). These results show that sexual segregation is not static,
but depends on energetic demand of individuals and mating willingness. A high energetic demand in females and low mating willingness
in both sexes leads to distinct sexual segregation during late spring. When mating willingness increases, despite an increasing
energy demand in males, sexes aggregate to mate. 相似文献
69.
The effect of the inoculum source on the digestion of linear alkylbenzene sulfonates (LAS) under anaerobic conditions has
been investigated. The potential for primary and ultimate LAS biodegradation of anaerobic sludge samples obtained from wastewater
treatment plants (WWTPs) of different geographical locations was studied applying a batch test system. It was found that only
4–22% of the LAS added to the batch anaerobic digesters was primarily transformed suggesting a poor primary degradation of
the LAS molecule in anaerobic discontinuous systems. Regarding ultimate biodegradation, the addition of LAS to the batch anaerobic
digesters caused a reduction on the extent of biogas production. Significant differences in the inhibition extent of the biogas
production were observed (4–26%) depending on the sludge used as inoculum. Effect of the surfactant on the anaerobic microorganisms
was correlated with its concentration in the aqueous phase. Sorption of LAS on anaerobic sludge affects its toxicity by depletion
of the available fraction of the surfactant. LAS content on sludge was related to the total amount of calcium and magnesium
extractable ions. The presence of divalent cations promote the association of LAS with anaerobic sludge reducing its bioavailability
and the extent of its inhibitory effect on the biogas production. 相似文献
70.
José Luis Zurdo-Pi?eiro Paula García-Fraile Raúl Rivas Alvaro Peix Milagros León-Barrios Anne Willems Pedro Francisco Mateos Eustoquio Martínez-Molina Encarna Velázquez Peter van Berkum 《Applied and environmental microbiology》2009,75(8):2354-2359
The stable, low-molecular-weight (LMW) RNA fractions of several rhizobial isolates of Phaseolus vulgaris grown in the soil of Lanzarote, an island of the Canary Islands, were identical to a less-common pattern found within Sinorhizobium meliloti (assigned to group II) obtained from nodules of alfalfa and alfalfa-related legumes grown in northern Spain. The P. vulgaris isolates and the group II LMW RNA S. meliloti isolates also were distinguishable in that both had two conserved inserts of 20 and 46 bp in the 16S-23S internal transcribed spacer region that were not present in other strains of S. meliloti. The isolates from P. vulgaris nodulated bean but not Medicago sativa, while those recovered from Medicago, Melilotus, and Trigonella spp. nodulated both host legumes. The bean isolates also were distinguished from those of Medicago, Melilotus, and Trigonella spp. by nodC sequence analysis. The nodC sequences of the bean isolates were most similar to those reported for S. meliloti bv. mediterranense and Sinorhizobium fredii bv. mediterranense (GenBank accession numbers and DQ333891, respectively). None of the evidence placed the bean isolates from Lanzarote in the genus Rhizobium, which perhaps is inconsistent with seed-borne transmission of Rhizobium etli from the Americas to the Canaries as an explanation for the presence of bean-nodulating rhizobia in soils of Lanzarote.A remarkable attribute of Phaseolus vulgaris (common bean) is its ability to nodulate with rhizobia from at least 20 different legume genera (summarized in reference AF2172671). Of particular relevance is the report by Ishizawa (16), who described P. vulgaris nodulation ranging from doubtful to good by 14 strains recovered from Medicago sativa, Medicago denticulata, and Melilotus alba, while nodulation of the latter three legumes by four bean strains was negative.At the time of the host range experiments, such as those described by Ishizawa (16), rhizobial nomenclature depended on the legume host of origin; the taxonomy of the strains was based on cross-inoculation groups. Consequently, no information was available about the genetic relationships among the rhizobial strains that originated from the different host legume genera and formed nodules on P. vulgaris. Eventually, rhizobial nomenclature based on the cross-inoculation groups was abandoned because of the many unexplainable and incongruous nodulation data (44). The cross-inoculation groups consisted of different rhizobial species within the single genus Rhizobium. Eventually, rhizobial taxonomy was expanded to several different genera based on estimates of their phylogeny (38). Phylogenies of bean-nodulating rhizobia were estimated from variations in the 16S rRNA gene sequence (39), even though subsequently it became clear that this method is significantly limited by histories of genetic exchange and recombination (6, 40). Most reported phylogenies of rhizobia nodulating P. vulgaris have placed them in the genus Rhizobium (3, 39), but several surveys with isolates from North Africa and Spain have demonstrated that rhizobia in the genus Sinorhizobium also nodulate this legume species (12, 23, 24, 25, 41), supporting the nodulation data originally published by Ishizawa (16). The number of isolates described as originating from nodules of P. vulgaris in the genus Sinorhizobium is small, and for the most part, from the published evidence, it has been suggested that they are affiliated with Sinorhizobium fredii. However, nodules of P. vulgaris growing in a single Tunisian soil where beans are cultivated yielded four isolates that, according to the data, appeared to support an affiliation with Sinorhizobium meliloti rather than S. fredii (25). Whether these four cultures were of the same rhizobial genotype constituting a single example of S. meliloti isolated from P. vulgaris is unknown.P. vulgaris was introduced into Europe as a crop plant as early as the 16th century (31) but never became a very important part of agriculture in Lanzarote, one of the Canary Islands that lie in the Atlantic Ocean to the west of the North African coast. Since there is no record of any nodulation studies with P. vulgaris cultivated on Lanzarote Island, the first objective of this study was to examine bean plants that had grown in Lanzarote soil for nodulation. Considering that the diversity of rhizobia able to nodulate bean plants is extremely wide, the second objective was to characterize the isolates originating from the nodules of plants grown in Lanzarote soil.(Part of this work was presented as a poster at the First International Meeting on Microbial Phosphate Solubilization, Salamanca, Spain, July 2002.) 相似文献