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151.
The catalytic activity of untreated and pre-reduced copper chromite in the hydrogenation of cyclic polyenes has been investigated. A comparison is made with the hydrogenation of polyunsaturated fatty acids of soybean oil. The role of the different oxidation states of the copper and the influence of the geometry of the substrate on the hydrogenation rate are discussed. 相似文献
152.
Bernard S. Morse Dennis Giuliani Maurice Soremekun Santo DiFino E. Regina Giuliani 《Cell proliferation》1974,7(2):113-123
The redistribution of hemopoietic tissue resulting from estrone-induced osteosclerosis in the mouse was studied. As the marrow was gradually replaced by bone, extramedullary hematopoiesis in the spleen increased at a rate sufficient to maintain hemopoietic homeostasis. The total numbers of colony forming units (CFU) in the tibia and spleen as well as the proportion of CFU in cycle was assessed. After five injections of estrone, tibial CFUs decreased to 2% of control values whereas splenic CFUs increased approximately nine-fold. The proliferative capacity of the splenic CFU was also increased in the estrone-treated animals. The increased numbers of splenic CFUs as well as the increased proliferative capacity of this compartment are probably related to the ability of extramedullary hematopoiesis in the spleen to compensate for a marrow that has been replaced by bone. 相似文献
153.
Similarity in Several Properties of Psychrophilic Bacteria Grown at Low and Moderate Temperatures 总被引:4,自引:2,他引:2 下载免费PDF全文
Hilmer A. Frank Ann Reid Leatrice M. Santo Norma A. Lum Sandra T. Sandler 《Applied microbiology》1972,24(4):571-574
Several properties of psychrophilic pseudomonads were studied with cells grown in batch culture in nutrient broth at 2 and 30 C. No differences were observed in the size, catalase activity, deoxyribonucleic acid, ribonucleic acid, or protein content of cells grown at either temperature. The importance of comparing physiologically similar cells is discussed. 相似文献
154.
155.
Fabrizio Briganti Demetrio Randazzo Andrea Scozzafava Debora Berti Piero Baglioni Patrizia Di Gennaro Enrica Galli Giuseppina Bestetti 《Journal of Molecular Catalysis .B, Enzymatic》1999,7(5-6):263-272
The whole cell biological conversion of naphthalene to (+)-cis-(1R,2S)-dihydroxy-1,2-dihydronaphthalene by the E. coli JM109(pPS1778) recombinant strain carrying the naphthalene dioxygenase and regulatory genes cloned from Pseudomonas fluorescens N3 in micellar systems has been investigated using biochemical and chemico-physical techniques. Reverse and direct micellar systems have been tested. Non-ionic surfactants (Tween and Triton X series) were found not to inhibit either the growth of the bacteria and the expression of the hydroxylating dioxygenase enzyme in such systems and were utilized in order to speed up the naphthalene conversion by increasing its solubility and also its bioavailability. The phase behavior of the direct micellar system was characterized through light scattering and other chemico-physical techniques. Further addition of isopropyl-palmitate 1–2% v/v to the micellar systems resulted in an increase of the apparent substrate concentration in solution and particularly its bioavailability thus allowing faster catalytic conversions resulting in an increase in productivity for the process. Since the cis-dihydrodiols are acquiring considerable potential as chiral pool synthons in asymmetric synthesis for a variety of industrial processes, possible applications for efficient small and large-scale production of such compounds are discussed. 相似文献
156.
ARPE-19 conditioned medium promotes neural differentiation of adipose-derived mesenchymal stem cells
Giuliana Mannino Martina Cristaldi Giovanni Giurdanella Rosario Emanuele Perrotta Debora Lo Furno Rosario Giuffrida Dario Rusciano 《World journal of stem cells》2021,13(11):1783-1796
BACKGROUNDAdipose-derived stem cells (ASCs) have been increasingly explored for cell-based medicine because of their numerous advantages in terms of easy availability, high proliferation rate, multipotent differentiation ability and low immunogenicity. In this respect, they have been widely investigated in the last two decades to develop therapeutic strategies for a variety of human pathologies including eye disease. In ocular diseases involving the retina, various cell types may be affected, such as Müller cells, astrocytes, photoreceptors and retinal pigment epithelium (RPE), which plays a fundamental role in the homeostasis of retinal tissue, by secreting a variety of growth factors that support retinal cells.AIMTo test ASC neural differentiation using conditioned medium (CM) from an RPE cell line (ARPE-19).METHODSASCs were isolated from adipose tissue, harvested from the subcutaneous region of healthy donors undergoing liposuction procedures. Four ASC culture conditions were investigated: ASCs cultured in basal Dulbecco''s Modified Eagle Medium (DMEM); ASCs cultured in serum-free DMEM; ASCs cultured in serum-free DMEM/F12; and ASCs cultured in a CM from ARPE-19, a spontaneously arising cell line with a normal karyotype derived from a human RPE. Cell proliferation rate and viability were assessed by crystal violet and MTT assays at 1, 4 and 8 d of culture. At the same time points, ASC neural differentiation was evaluated by immunocytochemistry and western blot analysis for typical neuronal and glial markers: Nestin, neuronal specific enolase (NSE), protein gene product (PGP) 9.5, and glial fibrillary acidic protein (GFAP).RESULTSDepending on the culture medium, ASC proliferation rate and viability showed some significant differences. Overall, less dense populations were observed in serum-free cultures, except for ASCs cultured in ARPE-19 serum-free CM. Moreover, a different cell morphology was seen in these cultures after 8 d of treatment, with more elongated cells, often showing cytoplasmic ramifications. Immunofluorescence results and western blot analysis were indicative of ASC neural differentiation. In fact, basal levels of neural markers detected under control conditions significantly increased when cells were cultured in ARPE-19 CM. Specifically, neural marker overexpression was more marked at 8 d. The most evident increase was observed for NSE and GFAP, a modest increase was observed for nestin, and less relevant changes were observed for PGP9.5. CONCLUSIONThe presence of growth factors produced by ARPE-19 cells in tissue culture induces ASCs to express neural differentiation markers typical of the neuronal and glial cells of the retina. 相似文献
157.
Frequent genes in rare diseases: panel‐based next generation sequencing to disclose causal mutations in hereditary neuropathies 下载免费PDF全文
Maike F. Dohrn Nicola Glöckle Lejla Mulahasanovic Corina Heller Julia Mohr Christine Bauer Erik Riesch Andrea Becker Florian Battke Konstanze Hörtnagel Thorsten Hornemann Saranya Suriyanarayanan Markus Blankenburg Jörg B. Schulz Kristl G. Claeys Burkhard Gess Istvan Katona Andreas Ferbert Debora Vittore Alexander Grimm Stefan Wolking Ludger Schöls Holger Lerche G. Christoph Korenke Dirk Fischer Bertold Schrank Urania Kotzaeridou Gerhard Kurlemann Bianca Dräger Anja Schirmacher Peter Young Beate Schlotter‐Weigel Saskia Biskup 《Journal of neurochemistry》2017,143(5):507-522
158.
Kate E. Smith Martin M. Shafer Debora Weiss Henry A. Anderson Patrick R. Gorski 《Biological trace element research》2017,175(1):33-41
This study aimed at evaluation of a relationship between blood selenium concentration (Se-B) and blood cystatin C concentration (CST) in a randomly selected population of healthy children, environmentally exposed to lead and cadmium. The studies were conducted on 172 randomly selected children (7.98 ± 0.97 years). Among participants, the subgroups were distinguished, manifesting marginally low blood selenium concentration (Se-B 40–59 μg/l), suboptimal blood selenium concentration (Se-B: 60–79 μg/l) or optimal blood selenium concentration (Se-B ≥ 80 μg/l). At the subsequent stage, analogous subgroups of participants were selected separately in groups of children with BMI below median value (BMI <16.48 kg/m2) and in children with BMI ≥ median value (BMI ≥16.48 kg/m2). In all participants, values of Se-B and CST were estimated. In the entire group of examined children no significant differences in mean CST values were detected between groups distinguished on the base of normative Se-B values. Among children with BMI below 16.48 kg/m2, children with marginally low Se-B manifested significantly higher mean CST values, as compared to children with optimum Se-B (0.95 ± 0.07 vs. 0.82 ± 0.15 mg/l, p < 0.05). In summary, in a randomly selected population of healthy children no relationships could be detected between blood selenium concentration and blood cystatin C concentration. On the other hand, in children with low body mass index, a negative non-linear relationship was present between blood selenium concentration and blood cystatin C concentration. 相似文献
159.
160.
SUMMARY: Since few years the problem of finding optimal solutions for drug or vaccine protocols have been tackled using system biology modeling. These approaches are usually computationally expensive. Our previous experiences in optimizing vaccine or drug protocols using genetic algorithms required the use of a high performance computing infrastructure for a couple of days. In the present article we show that by an appropriate use of a different optimization algorithm, the simulated annealing, we have been able to downsize the computational effort by a factor 10(2). The new algorithm requires computational effort that can be achieved by current generation personal computers. AVAILABILITY: Software and additional data can be found at http://www.immunomics.eu/SA/ 相似文献