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161.
Cryptococcosis as an opportunistic infection in immunodeficiency secondary to paracoccidioidomycosis
Gil Benard R. C. B. Gryschek A. J. S. Duarte M. A. Shikanai-Yasuda 《Mycopathologia》1996,134(2):65-69
We describe the case reports of two patients with immunodeficiency secondary to paracoccidioidomycosis (PCM) and opportunistic Cryptococcus neoformans infections. Secondary immunodeficiency likely occurred as a consequence of the intestinal loss of proteins and lymphocytes associated with malabsorption syndrome due to obstructed lymphatic drainage. Both patients had had severe abdominal involvement during the acute PCM disease. Immunological evaluation showed cellular and humoral immunity impairment. Cryptococcosis manifested as relatively well circumscribed lesions: osteolytic lesions of the skull in one patient, and pulmonary nodules in the other. The latter was treated surgically and with amphotericin B, whereas the other was treated with the combination amphotericin-B and flucytosine. Both patients had a good response to treatment with complete regression of the lesions. They have now 2 and 4 years of follow-up with maintenance therapy and no indication of reactivation of the infection. PCM also did not reactivate. The clinical and immunological characteristics of these patients are discussed and compared to the opportunistic C. neoformans infections of AIDS and transplant patients. 相似文献
162.
The chromosomal delta sequences of the yeast Saccharomyces cerevisiae were employed as recombination sites to integrate the bacterial neo(r) gene and the yeast SUC2 gene into the yeast genome. A dominate selection method employing the aminoglycoside antibiotic G418 was used. Transformation efficiencies and growth behaviors of the transformants were studied. Transformants were obtained with more than 40 integrations; the majority of insertions were tandem with a maximum of three different insertion sites utilized at one time. After 70-100 generations of growth in nonselective medium, the high copy number SUC2-neo(r) integrants were found to be unstable; only minor instability was observed for the neo(r) and low copy number SUC2-neo(r) integrants. (c) 1996 John Wiley & Sons, Inc. 相似文献
163.
The paper describes the local, national, European and wider-area framework, statutes, and formal and voluntary mechanisms for managing European estuaries. These aspects are discussed in relation to two large and representative estuarine systems, the Tagus, Portugal, and the Humber, on the English North Sea coast As estuaries are sites of many activities and uses, most of which are encouraged or at least condoned, management has the role of preventing and resolving conflicts between those uses and users. Accepted uses of estuaries include the discharge and dumping of waste materials, fin and shell-fisheries, conservation, land reclamation, natural usage, abstraction by industry, and recreation. Estuarine management is now being carried out within the constraints of local and regional government planning, planning and activities of water pollution control bodies, fisheries control bodies, and navigation and port authorities The Tagus and Humber estuaries support all of the above activities and uses, and have controls within a European legislative framework but have differing histories of management and planning in order to resolve conflicts. In addition the Humber is subject to controls placed on North Sea areas. The paper discusses the relevant national and European legislation (Directives) and accepted practices for management. Furthermore, the paper discusses the formulation and practice of estuarine management plans as used by various bodies (nature conservation, water quality and regional authority). It is of particular note that the lessons from these two estuaries are relevant to many other European estuaries. 相似文献
164.
The operational stability of the Candida rugosa lipase immobilized in a hydrophilic polyurethane foam was evaluated in consecutive batches for the glycerolysis of olive oil in n-hexane, aimed at the production of monoglycerides.Glycerol controlled the glycerolysis in the system under study, since it is both a substrate and a powerful water binder that reduces the water activity of the reaction medium and of the microenvironment. Two sets of experiments were carried out under different glycerol/triglyceride ratios. After 345 hours of consecutive 23 hours batches no lipase inactivation was observed.List of Symbols aw
thermodynamic activity of water
- DG
diglyceride (s)
- FAME
fatty acid methyl ester (s)
- FFA
free fatty acid (s)
- FID
flame ionization detector Gly glycerol
- MG
monoglyceride (s)
- TG
triglyceride (s)
- TLC
thin layer chromatography
The authors are grateful to Profs. P. Adlercreutz, Technical University of Lund, Sweden, and J.M.S. Cabral, Instituto Superior Técnico, Lisbon, Portugal, for inspiring discussions and advice, to Prof. Helena Pereira, Instituto Superior de Agronomia (ISA), Lisbon, Portugal, for the use of GC equipment and to Mrs. Marlene Dionísio, ISA, for invaluable help with some of the experimental work. 相似文献
165.
M. H. L. Ribeiro D. M. F. Prazeres J. M. S. Cabral M. M. R. da Fonseca 《Bioprocess and biosystems engineering》1995,12(1-2):95-102
l-tryptophan was produced froml-serine and indole by immobilized Escherichia coli cells in organic-aqueous systems. Selective adsorption was the method chosen to enable both product separation andl-serine reutilization. Amongst various adsorbents tested activated carbons and neutral polymeric resins (XAD-4 and XAD-7) showed good performance. The neutral resins could selectively concentrate thel-tryptophan from dilute aqueous solutions and adsorbed only 5% of the unconvertedl-serine. High separation factors (l-tryptophan/l-serine and indole/l-tryptophan) were obtained with these adsorbents. Despite a lower capacity, the XAD-7 resin had the advantage of desorbingl-tryptophan with basic or acidic solutions, while organic solvents were required to desorb, at the same concentration levels, this compound from XAD-4.In a packed bed column filled with XAD-4 resin or activated carbon, totall-tryptophan adsorption and recovery were achieved at linear velocities up to 5.0 cm/min and 3.2 cm/min respectively. Successive sorbent reutilization, following continuous sorption and elution steps, was carried out in packed bed columns with the neutral resins and activated carbon.Thel-form of tryptophan, after crystallization, was identified by HPTLC.List of Symbols HPLC
High Performance Liquid Chromatography
- HPTLC
High Performance Thin Layer Chromatography
- Trp
tryptophan
- Ser
Serine
-
A
amount of sorbent(g)
-
c
equilibrium solute concentration in the aqueous phase (g/dm3)
-
c
i
initial (before adding the sorbent) liquid phase concentration (g/dm3)
-
C
T
tryptophan concentration in the inlet solution (g/dm3)
-
C
To
tryptophan concentration in the outlet solution (g/dm3)
-
E
z
axial dispersion coefficient (m2/s)
-
k
experimental constant (Eq. 1, 2 and 3)
-
K
1
rate constant of adsorption (min–1)
-
L
column length(m)
-
n
experimental constant (eq. 1, 2 and 3)
-
q
equilibrium solid phase concentration (g solute/g sorbent)
-
q
max
maximum capacity of sorbent (g solute/g sorbent)
-
t
time(s)
-
v
liquid velocity (m/s)
-
V
volume of liquid phase(dm3)
-
V
e
eluted volume(dm3)
-
V
r
volume needed to saturate the column (dm3) 相似文献
166.
G. Guillen M. J. Leal A. Alvarez M. Delgado R. Silva L. Herrera 《Engineering in Life Science》1995,15(1):97-106
The 5C outer membrane protein, one of the N. meningitidis class 5 proteins, was preferably expressed in bacteria isolated from the nasopharynx and its role in adhering to the mucosal cells and invading them as well as the development of anti-5C antibodies in healthy carriers was demonstrated. Anti-5C monoclonal antibodies are bactericidal in the presence of the human complement. The immunodominant region of the 5C protein is highly conserved among the different strains of N. meningitidis, and the opc gene, which encodes the protein, does not seem to show antigenic variations. Here the isolation of the opc gene from the Cuban strain B:4:P1.15 by PCR (Polymerase Chain Reaction) is presented. Under the regulation of the tryptophan promoter, the gene was cloned and sequenced in E. coli with a high level of expression and fused to the amino-terminal end of the interleukin-2 gene. In the dot-blot experiments, the presence of the gene in those strains which did not express the protein in the whole cell ELISA was also detectable. 相似文献
167.
Medium-chain fatty acids (C6 to C12), produced by yeast metabolism during alcoholic fermentation, are known to be inhibitory to lactic acid bacteria. The purpose of this work was to clarify the effect of both ethanol and decanoic and dodecanoic acids on the growth and malolactic activity of aLeuconostoc oenos strain isolated from Portuguese red wine. Ethanol in concentrations up to 12% had no significant effect on malolactic activity but strongly inhibited cell growth. The fatty acids decanoic acid, in concentrations up to 12.5 mg l–1, and, dodecanoic acid up to 2.5 mg l–1 seemed to act as growth factors stimulating also malolactic activity; at higher concentrations they exerted an inhibitory effect. We found clear pH dependence between pH 3.0 and pH 6.0, between decanoic acid concentration and its effect on malolactic activity, indicating that the undissociated molecule is the active form. At pH 3.0 the results can be explained by considering that fatty acids enter the cell as protonated molecules and dissociate in the cytoplasm due to the higher internal pH, leading to increased intracellular hydrogenous concentration. This may be the basis of two different effects that contribute to the observed inhibition: decrease in the intracellular pH and dissipation of the transmembrane proton gradient, thus inhibiting intracellular enzymes and ApH-dependent transport systems. 相似文献
168.
Akira Akabayashi C.T.B.V. Zaia James I. Koenig Steven M. Gabriel Ivan Silva Sarah F. Leibowitz 《Peptides》1994,15(8):1437-1444
The peptide galanin (GAL), when injected into the rat hypothalamus, is known to stimulate feeding behavior and affect the secretion of various hormones, including insulin and the adrenal steroid, corticosterone. To determine whether endogenous peptide levels shift in relation to natural rhythms of feeding and circulating hormone levels, rats were sacrificed at different times of the light/dark cycle, and their GAL levels were measured, via radioimmunoassay, in medial hypothalamic dissections and micropunched hypothalamic areas. The results suggest the existence of two distinct diurnal rhythms for hypothalamic GAL. One rhythm, detected exclusively in the area of the SCN, is characterized by bimodal peaks of GAL, threefold higher than basal peptide levels, around the onset of the dark and light periods. The second rhythm shows a single peak of GAL towards the middle of the nocturnal feeding cycle, specifically between the third and sixth hour. This latter rhythm is evident in the dorsal region of the medial hypothalamus, localized specifically to the lateral portion of the PVN. Moreover, it is inversely related to circulating insulin but unrelated to the adrenal steroids, suggesting a possible association between this pancreatic hormone and GAL in the PVN. 相似文献
169.
170.
Josep Ll. Ventura Assumpció Estruch Gil Rodas Ramon Segura 《European journal of applied physiology and occupational physiology》1994,68(4):345-349
The metabolic responses induced by the ingestion of a beverage containing glucose (G), fructose (F) or placebo (W) 30 min before exercise of high intensity and intermediate duration have been investigated; in these conditions the energy processes are mostly dependent on aerobic reactions. A group of 11 male recreational sportsmen ran on a treadmill, at an intensity corresponding to 82% of peak oxygen consumption, until exhaustion on three different occasions (after ingestion of a beverage containing 75 g of G, 75 g of F or W). Plasma glucose, insulin, and lactic acid concentrations were determined just prior to the ingestion of the beverages, 30 min afterwards and 10 and 30 min after completion of the exercise. The mean endurance time was 644 (SD 261) s after the ingestion of G, 611 (SD 227) s after the ingestion of F and 584 (SD 189) s after the ingestion of the W (P < 0.05 between G and W). No differences in the oxygen uptake, respiratory quotient or lactate concentrations between the three trials were observed. Both plasma glucose and insulin concentrations determined in samples obtained immediately before the onset of exercise were higher when G was ingested than when F (P < 0.05 andP < 0.05, respectively) or W (P < 0.001 and P < 0.005, respectively) were ingested. These findings would suggest that the ingestion of G prior to an effort of intermediate duration may improve physical performance. 相似文献