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991.
Alessandra Micera Barbara Stampachiacchiere Antonio Di Zazzo Roberto Sgrulletta Magdalena Cortes Eduardo Maria Normando Alessandro Lambiase Stefano Bonini 《PloS one》2015,10(11)
Objective
In a previous study, we reported the upregulation of Nerve Growth Factor (NGF) and trkANGFR expression in Ocular Cicatricial Pemphigoid (OCP), an inflammatory and remodeling eye disease. Herein, we hypothesize a potential NGF-driven mechanism on fibroblasts (FBs) during OCP remodeling events. To verify, human derived OCP-FBs were isolated and characterized either at baseline or after NGF exposure.Materials and Methods
Conjunctival biopsies were obtained from 7 patients having OCP and 6 control subjects (cataract surgery). Both conjunctivas and primary FB cultures were characterised for αSMA, NGF and trkANGFR/p75NTR expression. Subcultures were exposed to NGF and evaluated for αSMA, NGF, trkANGFR/p75NTR expression as well as TGFβ1/IL4 release. For analysis, early and advanced subgroups were defined according to clinical parameters.Results
OCP-conjunctivas showed αSMA-expressing FBs and high NGF levels. Advanced OCP-FBs showed higher αSMA expression associated with higher p75NTR and lower trkANGFR expression, as compared to early counterparts. αSMA expression was in keeping with disease severity and correlated to p75NTR. NGF exposure did not affect trkANGFR levels in early OCP-FBs while decreased both αSMA/p75NTR expression and TGFβ1/IL4 release. These effects were not observed in advanced OCP-FBs.Conclusions
Taken together, these data are suggestive for a NGF/p75NTR task in the potential modulation of OCP fibrosis and encourages further studies to fully understand the underlying mechanism occurring in fibrosis. NGF/p75NTR might be viewed as a potential therapeutic target. 相似文献992.
Enrico Baldan Sebastiano Nigris Chiara Romualdi Stefano D’Alessandro Anna Clocchiatti Michela Zottini Piergiorgio Stevanato Andrea Squartini Barbara Baldan 《PloS one》2015,10(10)
We investigated the potential plant growth-promoting traits of 377 culturable endophytic bacteria, isolated from Vitis vinifera cv. Glera, as good biofertilizer candidates in vineyard management. Endophyte ability in promoting plant growth was assessed in vitro by testing ammonia production, phosphate solubilization, indole-3-acetic acid (IAA) and IAA-like molecule biosynthesis, siderophore and lytic enzyme secretion. Many of the isolates were able to mobilize phosphate (33%), release ammonium (39%), secrete siderophores (38%) and a limited part of them synthetized IAA and IAA-like molecules (5%). Effects of each of the 377 grapevine beneficial bacteria on Arabidopsis thaliana root development were also analyzed to discern plant growth-promoting abilities (PGP) of the different strains, that often exhibit more than one PGP trait. A supervised model-based clustering analysis highlighted six different classes of PGP effects on root architecture. A. thaliana DR5::GUS plantlets, inoculated with IAA-producing endophytes, resulted in altered root growth and enhanced auxin response. Overall, the results indicate that the Glera PGP endospheric culturable microbiome could contribute, by structural root changes, to obtain water and nutrients increasing plant adaptation and survival. From the complete cultivable collection, twelve promising endophytes mainly belonging to the Bacillus but also to Micrococcus and Pantoea genera, were selected for further investigations in the grapevine host plants towards future application in sustainable management of vineyards. 相似文献
993.
Patrick D. Brandt Susi Sturzenegger Varvayanis Tracey Baas Amanda F. Bolgioni Janet Alder Kimberly A. Petrie Isabel Dominguez Abigail M. Brown C. Abigail Stayart Harinder Singh Audra Van Wart Christine S. Chow Ambika Mathur Barbara M. Schreiber David A. Fruman Brent Bowden Christopher A. Wiesen Yvonne M. Golightly Chris E. Holmquist Daniel Arneman Joshua D. Hall Linda E. Hyman Kathleen L. Gould Roger Chalkley Patrick J. Brennwald Rebekah L. Layton 《PLoS biology》2021,19(7)
994.
Barbara A. Piperata Mark Hubbe Kammi K. Schmeer 《American journal of physical anthropology》2014,155(2):210-220
Recently scholars have advocated for the use of a critical biocultural approach in bioarchaeology, where osteological and dental markers of stress are used to understand the broader biosocial context of past populations. However, the ability to accomplish this task rests on the assumption that ultimate-level environmental stressors and well-being in the past can be reconstructed from the prevalence of pathologies in skeletal collections. Here we test this assumption using anemia prevalence in the Mexican Family Life Survey. Specifically we test three hypotheses: (1) that individuals sharing the same household are more likely to share anemia status; (2) anemia status is a predictor of economic status (a common proxy for broader environmental context); and (3) anemia status is related to self-rated health. Results demonstrate that: anemia status was not commonly shared between household members; there was a significant overlap in economic status between anemic and nonanemic individuals (i.e., anemia poorly predicted economic status) and; while anemia status was associated with self-perceived health, the majority of those who reported poor health were nonanemic while a significant number of those who reported very good health were anemic. We argue that these findings are likely related to variation in individual frailty, which is shaped by biological and cultural risk factors. Therefore, we advocate for greater incorporation of individual frailty into bioarchaeological investigations, and, in effort to overcome some of the difficulties associated with this task, increased use of data from living populations and greater collaboration between bioarchaeologists and human biologists. Am J Phys Anthropol 155:210–220, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
995.
996.
In Caenorhabditis elegans, germline apoptosis is promoted by egl-1 and ced-13 in response to meiotic checkpoint activation. We report that the requirement for these two factors depends on which checkpoints are active. We also identify a regulatory region of egl-1 required to inhibit germline apoptosis in response to DNA damage incurred during meiotic recombination. 相似文献
997.
Ajit G. Thomas Cliona M. O’Driscoll Joseph Bressler Walter E. Kaufmann Camilo J. Rojas Barbara S. Slusher 《Biochemical and biophysical research communications》2014
Glutaminase plays a critical role in the generation of glutamate, a key excitatory neurotransmitter in the CNS. Excess glutamate release from activated macrophages and microglia correlates with upregulated glutaminase suggesting a pathogenic role for glutaminase. Both glutaminase siRNA and small molecule inhibitors have been shown to decrease excess glutamate and provide neuroprotection in multiple models of disease, including HIV-associated dementia (HAD), multiple sclerosis and ischemia. Consequently, inhibition of glutaminase could be of interest for treatment of these diseases. Bis-2-(5-phenylacetimido-1,2,4-thiadiazol-2-yl)ethyl sulfide (BPTES) and 6-diazo-5-oxo-l-norleucine (DON), two most commonly used glutaminase inhibitors, are either poorly soluble or non-specific. Recently, several new BPTES analogs with improved physicochemical properties were reported. To evaluate these new inhibitors, we established a cell-based microglial activation assay measuring glutamate release. Microglia-mediated glutamate levels were significantly augmented by tumor necrosis factor (TNF)-α, phorbol 12-myristate 13-acetate (PMA) and Toll-like receptor (TLR) ligands coincident with increased glutaminase activity. While several potent glutaminase inhibitors abrogated the increase in glutamate, a structurally related analog devoid of glutaminase activity was unable to block the increase. In the absence of glutamine, glutamate levels were significantly attenuated. These data suggest that the in vitro microglia assay may be a useful tool in developing glutaminase inhibitors of therapeutic interest. 相似文献
998.
Abigail Perez-Valdespino Yunfeng Li Barbara Setlow Sonali Ghosh David Pan George Korza Florence E. Feeherry Christopher J. Doona Yong-Qing Li Bing Hao Peter Setlow 《Journal of bacteriology》2014,196(11):2077-2088
The Bacillus subtilis
spoVAEa and spoVAF genes are expressed in developing spores as members of the spoVA operon, which encodes proteins essential for the uptake and release of dipicolinic acid (DPA) during spore formation and germination. SpoVAF is likely an integral inner spore membrane protein and exhibits sequence identity to A subunits of the spore''s nutrient germinant receptors (GRs), while SpoVAEa is a soluble protein with no obvious signals to allow its passage across a membrane. However, like SpoVAD, SpoVAEa is present on the outer surface of the spore''s inner membrane, as SpoVAEa was accessible to an external biotinylation agent in spores and SpoVAEa disappeared in parallel with SpoVAD during proteinase K treatment of germinated spores. SpoVAEa and SpoVAD were also distributed similarly in fractions of disrupted dormant spores. Unlike spoVAD, spoVAEa is absent from the genomes of some spore-forming members of the Bacillales and Clostridiales orders, although SpoVAEa''s amino acid sequence is conserved in species containing spoVAEa. B. subtilis strains lacking SpoVAF or SpoVAEa and SpoVAF sporulated normally, and the spores had normal DPA levels. Spores lacking SpoVAF or SpoVAEa and SpoVAF also germinated normally with non-GR-dependent germinants but more slowly than wild-type spores with GR-dependent germinants, and this germination defect was complemented by ectopic expression of the missing proteins. 相似文献
999.
Airoldi C Zona C Sironi E Colombo L Messa M Aurilia D Gregori M Masserini M Salmona M Nicotra F La Ferla B 《Journal of biotechnology》2010,156(4):317-324
Curcumin derivatives with high chemical stability, improved solubility and carrying a functionalized appendage for the linkage to other entities, have been synthesized in a straightforward manner. All compounds retained Curcumin ability to bind Aβ peptide oligomers without inducing their aggregation. Moreover all Curcumin derivatives were able to stain very efficiently Aβ deposits. 相似文献
1000.
Markus Michael Müller Barbara Hörmann Christoph Syldatk Rudolf Hausmann 《Applied microbiology and biotechnology》2010,87(1):167-174
Rhamnolipids are biosurfactants with interesting physico-chemical properties. However, the main obstacles towards an economic
production are low productivity, high raw-material costs, relatively expensive downstream processing, and a lack of understanding
the rhamnolipid production regulation in bioreactor systems. This study shows that the sequenced Pseudomonas aeruginosa strain PAO1 is able to produce high quantities of rhamnolipid during 30 L batch bioreactor cultivations with sunflower oil
as sole carbon source and nitrogen limiting conditions. Thus PAO1 could be an appropriate model for rhamnolipid production
in pilot plant bioreactor systems. In contrast to well-established production strains, PAO1 allows knowledge-based systems
biotechnological process development combined with the frequently used heuristic bioengineering approach. The maximum rhamnolipid
concentration obtained was 39 g/L after 90 h of cultivation. The volumetric productivity of 0.43 g/Lh was comparable with
previous described production strains. The specific rhamnolipid productivity showed a maximum between 40 and 70 h of process
time of 0.088 gRL/gBDMh. At the same time interval, a shift of the molar di- to mono-rhamnolipid ratio from 1:1 to about 2:1 was observed. PAO1
not only seems to be an appropriate model, but surprisingly has the potential as a strain of choice for actual biotechnological
rhamnolipid production. 相似文献