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701.
702.
We developed a scale-up process design for the production of the 18 kDa heat shock recombinant protein from Mycobacterium leprae cloned in Saccharomyces cerevisiae (1). Here we present some of the costs associated with running a process based in our laboratory and pilot scale data. Based on these values and assuming the demand of the 18kDa-hsp protein as 500g/year we can review costs at least on an approximate basis. 相似文献
703.
704.
E C Bueno A J Vaz C A Oliveira L R Machado J A Livramento S R Mielli M Ueda 《Cytometry》1999,38(3):106-110
The events of the cellular immune response in neurocysticercosis (NC) are not fully understood. Studies of the CD3, CD3/CD4, CD3/CD8, CD45/CD19, and CD45/CD56 molecules and activation-related CD69 molecule in cells from the cerebrospinal fluid (CSF) and peripheral blood (PB) of patients with NC may provide a better elucidation of the inflammatory and immunological events occurring in this disease. Seven patients with NC and 3 individuals with other disorders were evaluated by a three-color flow cytometric method. CD69 was detected in a higher percentage of cells in all CSF samples from patients, but not in PB or CSF from the control group. The percentage of CD3+ cells did not differ significantly in CSF and PB cells from patients and controls. The predominance of CD3+CD8+ cells was observed in CSF from one patient and in PB from 2 patients, who were in stage III of the disease (inflammatory process). The percentage of CD45+CD19+ cells was higher in CSF than in PB from patients who presented anti-cysticercus antibodies in CSF. The percentage of CD45+CD56+ cells in CSF was higher than in PB, but this rate was similar to reference values reported by other authors. Our data suggest that the cytometric method applied to a larger number of CSF samples may provide a better understanding of the cell-mediated immune response involved in NC. 相似文献
705.
Silas P. Rodrigues Maura Da Cunha José A. Ventura Patricia Machado Bueno Fernandes 《Plant cell reports》2009,28(5):861-871
Spontaneous latex exudation is the main symptom of papaya sticky (meleira) disease caused by the Papaya meleira virus (PMeV), a double-stranded RNA (dsRNA) virus. This paper describes different effects of PMeV on papaya latex. Latex samples
were subjected to different histochemical tests to evaluate their chemical composition. Additionally, the integrity of the
latex particles was assessed by transmission and scanning electron microscopy analysis. Biochemical and micro- and macro-element
measurements were performed. PMeV dsRNA extraction was performed to evaluate the interaction of the virus with the latex particles.
Sticky diseased latex was positive for alkaloid biosynthesis and showed an accumulation of calcium oxalate crystals. PMeV
also increased H2O2 synthesis within sticky diseased laticifers. The protein, sugar and water levels were altered, probably due to chemical changes.
The morphology of the latex particles was further altered; PMeV particles seemed to be bound to the latex particles. The alkaloid
and H2O2 biosynthesis in the papaya laticifers indicate a papaya defense response against PMeV. However, such efforts failed, as the
virus affected the plant latex. The effects described here suggest some advantages of the infection process, including facilitating
the movement of the virus within the papaya plant. 相似文献
706.
707.
708.
Y Menezo A Cupo L Bueno 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1987,304(12):337-340
In search of early pregnancy factors, we detected by radioimmunoassay the presence of enkephalin in bovine and human corpus luteum. In vitro met-enkephalin release by bovine corpus luteum is about 0.5 to 1 pmole/mg of fresh tissue/24 hrs. The content of the fresh tissue is between 0.7 and 1.9 pmoles per gram of human tissue, and 0.9 pmoles for bovine tissue. Furthermore, we determined the presence of leu-enkephalin and met-enkephalin Arg-Gly-Leu to. The ratios observed confirm a pro-enkephalin A expression in the ovary. Opiates or opioid-like peptides are present in the female genitalia at the time of early embryo development. The roles of these opioid peptides is discussed in term of ovum transport, granulosa cell physiology and early pregnancy factors. 相似文献
709.
Myocyte differentiation and body wall muscle regeneration in the planarian Girardia tigrina 总被引:2,自引:0,他引:2
F. Cebrià Marcelo Vispo P. Newmark David Bueno Rafael Romero 《Development genes and evolution》1997,207(5):306-316
Freshwater planarians (Platyhelminthes, Turbellaria) show a great degree of morphological plasticity, making them a useful
model for studying cell differentiation and pattern restoration processes during regeneration. Using confocal microscopy and
a monoclonal antibody specific for muscle cells (TMUS-13), we have monitored the restoration of the body wall musculature
during head regeneration in whole-mount organisms. Our results show that until the 4th day of regeneration the blastema is
occupied by very disorganized muscle fibers, that from this moment become progressively organized restoring the original muscle
pattern. In addition to recognizing mature muscle cells, TMUS-13 also recognizes differentiating myocytes, allowing us to
trace the origin of newly formed muscle cells. We report that myocytes are detected in the postblastema region as early as
day 1 of regeneration. This is the first demonstration that, in addition to serving as a proliferative zone as previously
described, overt differentiation begins in the postblastema, at least for muscle cells. We also show that the TMUS13 antigen
is the myosin heavy-chain gene from planarians.
Received: 15 April 1997 / Accepted: 7 July 1997 相似文献