Background: The major stress response to critical illness leads to a catabolic state and loss of lean body mass. Aims: To test whether an increased rate of creatinine excretion might provide unique ...and timely information to monitor cell catabolism; to relate this information to balances of cell constituents (nitrogen, potassium, phosphate and magnesium); to evaluate the effectiveness of nutritional therapy to reverse this catabolic process. Design: Prospective observational study. Methods: Children with severe traumatic brain injury admitted to the paediatric critical care units of The Hospital for Sick Children, Toronto, Canada and Hospital das Clínicas, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil were studied. Complete 24 h urine collections were obtained for measurement of creatinine excretion rate and daily balances of nitrogen, potassium, phosphate and magnesium. Results: Seventeen patients were studied for 3–10 days. On Day 1, all had negative balances for protein and phosphate. Balances for these intracellular constituents became positive when protein intake was ⩾1 g/kg/day and energy intake was ⩾50% of estimated energy expenditure (P < 0.0001). Creatinine excretion rate was positively correlated with the urea appearance rate (r = 0.60; P < 0.0001), and negatively with protein balance (r = -0.45; P < 0.0001). Sepsis developed in four patients; before its clinical detection, there were negative balances for all intracellular markers and an abrupt rise in the excretion of creatinine. Conclusions: Negative balances of intracellular components and an increase in rate of creatinine excretion heralded the onset of catabolism.
Twenty-two azo dyes were used to study the influence of substituents on azo dye biodegradability and to explore the possibility of enhancing the biodegradabilities of azo dyes without affecting their ...properties as dyes by changing their chemical structures. Streptomyces spp. and Phanerochaete chrysosporium were used in the study. None of the actinomycetes (Streptomyces rochei A10, Streptomyces chromofuscus A11, Streptomyces diastaticus A12, S. diastaticus A13, and S. rochei A14) degraded the commercially available Acid Yellow 9. Decolorization of monosulfonated mono azo dye derivatives of azobenzene by the Streptomyces spp. was observed with five azo dyes having the common structural pattern of a hydroxy group in the para position relative to the azo linkage and at least one methoxy and/or one alkyl group in an ortho position relative to the hydroxy group. The fungus P. chrysosporium attacked Acid Yellow 9 to some extent and extensively decolorized several azo dyes. A different pattern was seen for three mono azo dye derivatives of naphthol. Streptomyces spp. decolorized Orange I but not Acid Orange 12 or Orange II. P. chrysosporium, though able to transform these three azo dyes, decolorized Acid Orange 12 and Orange II more effectively than Orange I. A correlation was observed between the rate of decolorization of dyes by Streptomyces spp. and the rate of oxidative decolorization of dyes by a commercial preparation of horseradish peroxidase type II, extracellular peroxidase preparations of S. chromofuscus A11, or Mn(II) peroxidase from P. chrysosporium. Ligninase of P. chrysosporium showed a dye specificity different from that of the other oxidative enzymes. These results suggest that peroxidase enzymes are involved in the initial azo dye biodegradation process.
Pathways for the degradation of 3,5-dimethyl-4-hydroxy-azobenzene-4'-sulfonic acid (I) and 3-methoxy-4-sulfonic acid (I) and 3-methoxy-4-hydroxyazobenzene-4'-sulfonamide (II) by the manganese ...peroxidase and ligninase of Phanerochaete chrysosporium and by the peroxidase of Streptomyces chromofuscus have been proposed. Twelve metabolic products were found, and their mechanisms of formation were explained. Preliminary oxidative activation of the dyes resulted in the formation of cationic species, making the molecules vulnerable to the nucleophilic attack of water. Two types of hydrolytic cleavage were observed. Asymmetric splitting gave rise to quinone and diazene derivatives, while symmetric splitting resulted in the formation of quinone monoimine and nitroso derivatives. These unstable intermediates underwent further redox, oxidation, and hydrolytic transformation, eventually furnishing 11 organic products and ammonia
Five (14)C-radiolabeled azo dyes and sulfanilic acid were synthesized and used to examine the relationship between dye substitution patterns and biodegradability (mineralization to CO2) by a ...white-rot fungus and an actinomycete. 4-Amino-U-(14)Cbenzenesulfonic acid and 4-(3-sulfo-4-aminophenylazo)-U-(14)Cbenzenesulfonic acid were used as representative compounds having sulfo groups or both sulfo and azo groups. Such compounds are not known to be present in the biosphere as natural products. The introduction of lignin-like fragments into the molecules of 4-amino-U-(14)Cbenzenesulfonic acid and 4-(3-sulfo-4-aminophenylazo)-U-(14)Cbenzenesulfonic acid by coupling reactions with guaiacol (2-methoxyphenol) resulted in the formation of the dyes 4-(3-methoxy-4-hydroxyphenylazo)-U-(14)Cbenzenesulfonic acid and 4-(2-sulfo-3'-methoxy-4'-hydroxy-azobenzene-4-azo)-U-(14)C benzenesulfonic acid, respectively. The synthesis of acid azo dyes 4-(2-hydroxy-1-naphthylazo)-U-(14)C benzenesulfonic acid and 4-(4-hydroxy-1-naphthylazo)-U-(14)Cbenzenesulfonic acid also allowed the abilities of these microorganisms to mineralize these commercially important compounds to be evaluated. Phanerochaete chrysosporium mineralized all of the sulfonated azo dyes, and the substitution pattern did not significantly influence the susceptibility of the dyes to degradation. In contrast, Streptomyces chromofuscus was unable to mineralize aromatics with sulfo groups and both sulfo and azo groups. However, it mediated the mineralization of modified dyes containing lignin-like substitution patterns. This work showed that lignocelluloytic fungi and bacteria can be used for the biodegradation of anionic azo dyes, which thus far have been considered among the xenobiotic compounds most resistant to biodegradation. Very specific structural changes in the azo dye molecules enhanced their biodegradability
The lignocellulose-degrading abilities of 11 novel actinomycete strains isolated from termite gut were determined and compared with that of the well-characterized actinomycete, Streptomyces ...viridosporus T7A. Lignocellulose bioconversion was followed by (i) monitoring the degradation of 14Clignin- and 14Ccellulose-labeled phloem of Abies concolor to 14CO2 and 14C-labeled water-soluble products, (ii) determining lignocellulose, lignin, and carbohydrate losses resulting from growth on a lignocellulose substrate prepared from corn stalks (Zea mays), and (iii) quantifying production of a water-soluble lignin degradation intermediate (acid-precipitable polymeric lignin). The actinomycetes were all Streptomyces strains and could be placed into three groups, including a group of five strains that appear superior to S. viridosporus T7A in lignocellulose-degrading ability, three strains of approximately equal ability, and three strains of lesser ability. Strain A2 was clearly the superior and most effective lignocellulose decomposer of those tested. Of the assays used, total lignocellulose weight loss was most useful in determining overall bioconversion ability but not in identifying the best lignin-solubilizing strains. A screening procedure based on 14CO2 evolution from 14C-ligninlignocellulose combined with measurement of acid-precipitable polymeric lignin yield was the most effective in identifying lignin-solubilizing strains. For the termite gut strains, the pH of the medium showed no increase after 3 weeks of growth on lignocellulose. This is markedly different from the pattern observed with S. viridosporus T7A, which raises the medium pH considerably. Production of extracellular peroxidases by the 11 strains and S. viridosporus T7A was followed for 5 days in liquid cultures. On the basis of an increase of specific peroxidase activity in the presence of lignocellulose in the medium, the actinomycetes could be placed into the same three groups
The identification of ricin toxin A‐chain (RTA) epitopes and the molecular context in which they are recognized will allow strategies to be devised that prevent/suppress an anti‐RTA immune response ...in patients treated with RTA‐based immunotoxins. RTA‐specific human T‐cell lines and T‐cell clones were produced by in vitro priming of PBMC. The T‐cell clones used a limited set of Vβ chains (Vβ1, Vβ2 and Vβ8) to recognize RTA epitopes. The use of RTA deletion mutants demonstrated that T‐cell lines and T‐cell clones from three out of four donors responded to RTA epitopes within the domain D124‐Q223, whereas one donor recognized the region I1‐D124. The response to RTA peptides of T‐cell lines and T‐cell clones from two donors allowed the identification of immunogenic segments (D124‐G140 and L161‐T190) recognized in the context of different HLA‐DRB1 alleles (HLA‐DRB1*0801, and HLA‐DRB1*11011 and B1*03011, respectively). The response to L161‐T190 was investigated in greater detail. We found that the HLA‐DRB1*03011 allele presents a minimal epitope represented by the sequence I175‐Y183 of RTA, whereas the HLA‐DRB1*11011 allele presents the minimal epitope M174‐I184. RTA peptides and an I175A RTA point mutant allowed us to identify I175 as a crucial residue for the epitope(s) recognized by the two HLA‐DRB1 alleles. Failure of T‐cell clones to recognize ribosome inactivating proteins (RIPs) showing sequences similar but not identical to RTA further confirmed the role of I175 as a key residue for the epitope recognized in the context of HLA‐DRB1*11011/03011 alleles.
To compare the visual outcomes, reading performance, and quality of life (QoL) of working-age cataractous patients bilaterally implanted with 3 different diffractive multifocal intraocular lenses ...(MIOLs).
Two-center, randomized, prospective, double-masked study.
Sixty-three consecutive patients (126 eyes) seen at Ophthalmology Section, Palermo and Florence University, Italy, randomized to receive the ReSTOR SN6AD3 (Alcon Laboratories, Inc, Irvine, CA) (20 patients, group A), ReSTOR SN6AD1 (Alcon Laboratories, Inc) (21 patients, group B), or TECNIS ZMA00 (Abbott Medical Optics, Santa Ana, CA) (22 patients, group C) MIOL.
Phacoemulsification.
One-year follow-up differences among the 3 MIOL groups in visual acuity, reading performance by MNREAD (Minnesota Laboratory for Low-Vision Research, University of Minnesota, Minneapolis, MN) reading acuity (RA), critical print size (CPS), and maximum reading speed (MRS) under mesopic and photopic conditions.
Photopic and mesopic contrast sensitivity (CS) by Pelli-Robson test and patient satisfaction by National Eye Institute Refractive Error Quality of Life Instrument-42 (NEI RQL-42) questionnaire.
Mean photopic uncorrected near visual acuity (UNVA), distance-corrected near visual acuity (DCNVA), and corrected near visual acuity (CNVA) did not differ among groups, with a preferred reading distance greater in group B (P< 0.0005). Photopic distance-corrected intermediate visual acuity (DCIVA) was best in group B (P = 0.001) and better in group C than in group A. Mesopic UNVA and DCNVA were worse in groups A and B compared with group C (P< 0.0005 in both cases), with better DCNVA in group B than in group A (P = 0.031). Mesopic uncorrected intermediate visual acuity (UIVA) and DCIVA were worst in group A, with better results in group C (P< 0.0005 and P = 0.001, respectively). Mesopic MNREAD RA was better in group C (P = 0.02), and mesopic MRS was higher in groups B and C than in group A (P = 0.002). The QoL scores by the NEI RQL-42 test exhibited no differences among groups in 9 over 13 scales. "Near vision" (P = 0.005), "symptoms" (P = 0.001), and "satisfaction with correction" scale scores (P = 0.030) were lowest in group A, and "appearance" scale score was lowest in group B (P = 0.045).
Newer-generation aspheric diffractive MIOLs, especially low-add hybrid apodized or full diffractive, are highly suited for working-age cataractous patients in terms of visual outcomes, reading performance, and QoL. Intrinsic optical differences, such as optimization for computer or dim-light working, or night driving, could be useful tools to customize the IOL in each single case.
The cytoreductive effects of anti-transferrin receptor (anti-TfnR) immunotoxins (ITs) and of ricin toxin against tumour micromasses have been evaluated in a multicellular tumour spheroid (MTS) model. ...More than 600 (656) MTSs obtained with human breast carcinoma (MCF7) or rat glioblastoma (9L) cell lines were treated individually with ITs or toxin and the effects induced by the treatment were measured for each MTS as volume variation vs time by applying the Gompertz growth model. Two dose-dependent patterns of MTS growth were observed in MTSs of both cell lines in response to IT or toxin treatment: (1) complete inhibition of MTS growth ('sterilisation'); and (2) partial/complete inhibition ('heterogeneous response'). Within the range of IT or toxin concentrations resulting in partial inhibition of MTS growth, the sensitivity of treated MTSs was extremely heterogeneous (the cytoreductive effects varying between 0.1 and 4 logs of cells killed for a given IT or toxin concentration). Analysis of the post-treatment regrowth kinetics indicated that treated non-sterilised and control MTSs reached the same final limiting volumes. However, the doubling time estimated for the surviving cells of treated MCF7 and 9L MTSs ranged between 15 and 50 h, indicating that each MTS had individual growing potential. In conclusion, our results indicate that at substerilising IT concentrations individual heterogenicity of MTSs may greatly influence the cytoreductive potential of ITs. An implication of our study is that the efficacy of an IT treatment in eradicating disseminated micrometastases may not be predictable a priori. The MTS model that we describe in this paper may help in dissecting out factors limiting the effect of ITs in three-dimensional tumours.
Actinomycete strains isolated from 2,4,6-trinitrotoluene (TNT)-contaminated and uncontaminated environments were compared for TNT tolerance and abilities to transform TNT. Regardless of previous TNT ...exposure history, no significant differences in TNT tolerance were seen among strains. Selected strains did not significantly mineralize 14CTNT. The actinomycetes did, however, transform TNT into reduced intermediates. The data indicate that, in actinomycete-rich aerobic environments like composts, actinomycetes will transform TNT into intermediates which are known to form recalcitrant polymers
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