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91.
Pollero Ricardo J. Gaspar María L. Cabello Marta 《World journal of microbiology & biotechnology》2001,17(8):805-810
Several properties of the lipolytic activity exhibited by the conidial fungus Phoma glomerata were studied. Lipolytic activity in an aqueous buffer medium was measured on triacylglycerol, phosphoglyceride and cholesterol ester under different experimental conditions. The effect of storage temperature on the stability of the hydrolytic activity, and optimal conditions of temperature and time of maximal activity were determined. The optimal conditions for maximal lipolytic activity were found to be 40–50 °C and 1 h. The activity released to the medium by 1 mg cells for 1 h at 40 °C was stated as the enzyme released unit (ERU). The protein fraction of MW > 50 kDa obtained by ultrafiltration of the medium, was active on the three substrates assayed, and it showed a non-specific hydrolytic activity on both the 1- and 2-acyl esters either in the neutral glyceride or in the phosphoglyceride. A protein of M
r approx. 75 kDa was the only one that showed esterase activity. The crude medium, stored at –15 °C, maintained its initial hydrolytic activity on triacylglycerol for at least 42 days, though when it was kept for 10 days at 4 °C, the activity fell to 50%. Kinetic parameters using substrates such as triolein (TO), dipalmitoyl phosphatidylcholine (DPPC) and cholesteryl oleate (ChoO), were comparatively evaluated. The activity of the enzyme in the hydrolysis of TO showed the highest values, whereas the maximal specific activities were less when the enzyme was assayed against DPPC and ChoO. 相似文献
92.
M. Bouchet Th. Gaspar T. A. Thorpe 《In vitro cellular & developmental biology. Plant》1978,14(10):819-823
Summary A comparison of the soluble and cell-wall-bound isoperoxidases of normal auxin-requiring and auxin-independent (habituated)
tobacco callus revealed that normal tissues contained a higher level of isoperoxidases. There were also qualitative differences
in these isoperoxidases. Partially purified soluble and ionically bound isoperoxidases of normal callus likewise exhibited
higher auxin-oxidase activities. Normal tissues also were found to contain higher levels of auxin-oxidase inhibitors (auxin
protectors). Overall, however, the data indicate that there is a higher rate of auxin destruction in normal tobacco callus
than in habituated tissue. This presumably leads to insufficient endogenous auxin for growth.
This study was supported in part by grants to T.G. from the Center IRSIA d'Etude de la Reproduction végétale and the FRFC
Contract No. 2.9009. it Was carried out while T.A.T. was the holder of a senior Fellowship under the NATO senior Scientists
Program. 相似文献
93.
94.
de Dios Carolina Yu Feng Hua García Fernando Cebollada Alfonso Armelles Gaspar 《Plasmonics (Norwell, Mass.)》2018,13(6):2061-2066
Plasmonics - We analyze the optical and chirooptical response of two Au nanorods vertically separated and with arbitrary relative in-plane orientation. The use of a simple model of Lorentzian... 相似文献
95.
Winnie Ip Juliana M.F. Silva Hubert Gaspar Arindam Mitra Shreenal Patel Kanchan Rao Robert Chiesa Persis Amrolia Kimberly Gilmour Gul Ahsan Mary Slatter Andrew R. Gennery Robert F. Wynn Paul Veys Waseem Qasim 《Cytotherapy》2018,20(6):830-838
Background
Adenovirus (ADV) reactivation can cause significant morbidity and mortality in children after allogeneic stem cell transplantation. Antiviral drugs can control viremia, but viral clearance requires recovery of cell-mediated immunity.Method
This study was an open-label phase 1/2 study to investigate the feasibility of generating donor-derived ADV-specific T cells (Cytovir ADV, Cell Medica) and to assess the safety of pre-emptive administration of ADV-specific T cells in high-risk pediatric patients after allogeneic hematopoietic stem cell transplantation (HSCT) to treat adenoviremia. Primary safety endpoints included graft-versus-host disease (GvHD), and secondary endpoints determined antiviral responses and use of antiviral drugs.Results
Between January 2013 and May 2016, 92 donors were enrolled for the production of ADV T cells at three centers in the United Kingdom (UK), and 83 products were generated from 72 mobilized peripheral blood harvests and 20 steady-state whole blood donations. Eight children received Cytovir ADV T cells after standard therapy and all resolved ADV viremia between 15 and 127 days later. ADV-specific T cells were detectable using enzyme-linked immunospot assay (ELISpot) in the peripheral blood of all patients analyzed. Serious adverse events included Grade II GvHD, Astrovirus encephalitis and pancreatitis.Conclusion
The study demonstrates the safety and feasibility of pre-emptively manufacturing peptide pulsed ADV-specific cells for high-risk pediatric patients after transplantation and provides early evidence of clinical efficacy. 相似文献96.
B. Bisbis J.P. Billard C. Huault C. Kevers F. Le Dily T. Gaspar 《Biologia Plantarum》1997,40(4):493-497
5-Aminolevulinic acid synthase (ALAS) has been detected in a normal (auxin- and cytokinin-dependent) green sugar beet callus under light and under darkness. ALAS activity was lower when the callus was grown under light. The supply of precursors of the Shemin pathway (glycine and succinate) to dark-grown callus enhanced considerably the capacity of the 5-aminolevulinic acid (ALA) formation. Glutamate, -aminobutyrate or -ketoglutarate also increased ALA accumulation. Such an accumulation was also obtained after inhibition of polyamine synthesis. The results show that glutamate or its derivatives might feed the Shemin pathway in conditions preventing glutamate to be used through the Beale pathway. 相似文献
97.
M.A. Bernal B. Bisbis M.A. Pedreño C. Kevers C. Penel T. Gaspar 《Biologia Plantarum》1997,39(2):161-168
Habituated sugar beet calli have been characterized as having a deficiency in some tetrapyrrole containing compounds. However,
peroxidases might be dissociated from the other tetrapyrrole containing compounds. When light-cultured normal and habituated
calli were transferred to darkness their peroxidase activity reduced and increased, respectively, indicating that habituation
could not strictly be characterized by a deficiency in peroxidase content but rather by a different regulation of its activity.
This regulation could be mediated through soluble effectors which act as potential peroxidase inhibitors and/or by a differential
expression of the peroxidase isoenzyme patterns which were present in these tissues in both light and darkness. The different
peroxidase activity and the nature of acidic and basic peroxidase isoenzymes in normal and habituated tissues could explain
the different features of both types of cultures.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
98.
99.
Max R. Gaspar 《The Western journal of medicine》1954,81(3):214-217
During a 12-year period at the Los Angeles County General Hospital there were 364 cases of resection and anastomosis of the small intestine which were classified and studied. Particular attention was paid to the methods of anastomosis. There were more wound infections, fistulas and otherwise faulty anastomosis with the open than with the closed technique. In the presence of a peritoneal cavity not previously contaminated by bowel content, a closed anastomosis is better and safer than an open anastomosis. 相似文献