Influence of initial chemical composition and characteristics of pulps on the production and properties of lignocellulosic nanofibers.

This work aimed to study the influence of the initial chemical composition (glucans, lignin, xylan, and mannans), intrinsic viscosity, and carboxylate groups of pulps on the production process and final properties of lignocellulosic nanofibers (LCNF). Pulps of pine sawdust, eucalyptus sawdust, and sugarcane bagasse subjected to conventional pulping and highly oxidized processes were the starting materials. The LCNF were obtained by TEMPO mediated oxidation and mechanical fibrillation with a colloidal grinder. The nanofibrillation degree, chemical charge content, rheology, laser profilometry, cristallinity and atomic force microscopy were used to characterize the LCNF. The carboxylate groups, hemicelluloses and lignin of the initial pulps were important factors that affected the production process of LCNF. The results revealed that intrinsic viscosity and carboxylate groups of the initial pulps affected LCNF production process, whereas lignin and hemicelluloses influenced the viscosity of LCNF aqueous suspensions, the roughness of LCNF films, and the carboxylate groups content of LCNF.

Thioredoxin and glutaredoxin regulate metabolism through different multiplex thiol switches.

The aim of the present study was to define the role of Trx and Grx on metabolic thiol redox regulation and identify their protein and metabolite targets. The hepatocarcinoma-derived HepG2 cell line under both normal and oxidative/nitrosative conditions by overexpression of NO synthase (NOS3) was used as experimental model. Grx1 or Trx1 silencing caused conspicuous changes in the redox proteome reflected by significant changes in the reduced/oxidized ratios of specific Cys's including several glycolytic enzymes. Cys91 of peroxiredoxin-6 (PRDX6) and Cys153 of phosphoglycerate mutase-1 (PGAM1), that are known to be involved in progression of tumor growth, are reported here for the first time as specific targets of Grx1. A group of proteins increased their CysRED/CysOX ratio upon Trx1 and/or Grx1 silencing, including caspase-3 Cys163, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) Cys247 and triose-phosphate isomerase (TPI) Cys255 likely by enhancement of NOS3 auto-oxidation. The activities of several glycolytic enzymes were also significantly affected. Glycolysis metabolic flux increased upon Trx1 silencing, whereas silencing of Grx1 had the opposite effect. Diversion of metabolic fluxes toward synthesis of fatty acids and phospholipids was observed in siRNA-Grx1 treated cells, while siRNA-Trx1 treated cells showed elevated levels of various sphingomyelins and ceramides and signs of increased protein degradation. Glutathione synthesis was stimulated by both treatments. These data indicate that Trx and Grx have both, common and specific protein Cys redox targets and that down regulation of either redoxin has markedly different metabolic outcomes. They reflect the delicate sensitivity of redox equilibrium to changes in any of the elements involved and the difficulty of forecasting metabolic responses to redox environmental changes.

Thiol redox proteomics identifies differential targets of cytosolic and mitochondrial glutaredoxin-2 isoforms in Saccharomyces cerevisiae. Reversible S-glutathionylation of DHBP synthase (RIB3).

Yeast Grx2 plays a role in the antioxidant glutathione linked defense acting on the redox status of protein cysteines, but the exact action or its specificity is not known. Moreover, it localizes in cytosol and mitochondria where it can exert different functions. To search for functions of Grx2 we determined the differential "Thiolic Redox Proteome" of control and peroxide-treated yeast mutant cells lacking the gene for Grx2 or expressing Grx2 exclusively in the mitochondria. Forty-two proteins have been identified that have alternative redox oxidation states as a consequence of Grx2 absence from the cell or expression in the mitochondria and absence from the cytosol. The precise cysteine residues affected have been mapped for each protein. One target protein, Rib3p, which has as yet an undefined function in respiration, was confirmed to have its Cys56 reversibly S-glutathionylated in vitro in a Grx2p dependent process. Grx2-dependent redox changes in key enzymes of glutamate consuming amino acid biosynthetic pathways could favor glutathione biosynthesis. Other target proteins are involved in membrane fusion, cell wall structure and ribosome assembly, but others are of unknown function. These results provide clues on the metabolic hot spots of redox regulatory mechanisms.

Effects of oxidative stress on protein thiols and disulphides in Mytilus edulis revealed by proteomics: actin and protein disulphide isomerase are redox targets.

Many proteins contain cysteines which are sensitive to oxidation. This is sometimes reversible through interaction with glutathione, glutaredoxin or thioredoxin systems making these proteins potential sensors of oxidative stress. In this study we analysed whether there was an increase in mixed disulphide bond (-S-S-) formation in the blue mussel Mytilus edulis in response to menadione. This was achieved by initially blocking reduced thiols with N-ethylmaleimide, -S-S- were then reduced with dithiothreitol (DTT) and labelled with 5-iodoacetamidofluorescein (5-IAF). Free -SHs were also labelled directly with 5-IAF. Separations were performed on 1D or 2D SDS PAGE and images analysed. There was an increase in -S-S- in response to menadione and detection of changes in oxidised proteins was easier than that of changes in the amount of reduced proteins. Protein disulphide isomerase (PDI) was labelled both as -SH and -S-S-, underlining its involvement in the redox status of the animal. A glutathione transferase (GST P1-1) forms an inter-chain disulphide bridge in response to menadione.

Restless legs syndrome in patients with chronic venous disorders: an untold story.

OBJECTIVES: To prospectively study the profile of restless leg syndrome (RLS) in patients presenting to a phlebology practice. METHODS: The study uses prospective questionnaire and clinical observation study. In all, 174 consecutive patients and 174 matched controls were evaluated in detail. The diagnosis of restless legs syndrome (RLS) was established by the International RLS study group (IRLSSG) criteria. Detailed clinical, systemic and Duplex ultrasound evaluations were done to establish the presence of chronic venous disorders (CVD) (reflux > 0.5 s on augmentation manoeuvers and revised clinical, aetiological, anatomical and pathological [CEAP] criteria). RESULTS: Of the 174 consecutive subjects studied (22M: 152F), 63 (36%) had evidence of RLS compared with only 34 of 174 of the controls (19%, P < 0.05). Sixty-two (98%) of these RLS-positive study subjects were subsequently diagnosed with CVD. In comparison, 31 (91%) of the RLS-positive control subjects (n = 34) were found to have CVD. This prevalence of CVD was comparable with RLS-positive study subjects, but was significantly higher than the prevalence in CVD in RLS-negative controls (P < 0.01). Only three (9%) of the controls had RLS without CVD. RLS-positive subjects were typically women above the age of 40 years (P < 0.01 vs. men, P < 0.01 vs. below 40 years). A significant difference in clinical presentation in the study subjects was the high prevalence of leg cramps in the RLS-positive subjects (P < 0.01). None of the patients with RLS in this series gave history of anaemia, chronic renal failure or an established psychiatric or neurological disease as found pathognomic for RLS by others. CONCLUSIONS: RLS appears to be a common overlapping clinical syndrome in patients with CVD. Prospective blinded therapeutic trials are planned to study the influence of definitive treatments for CVD on sequential RLS scores.

Redox proteomics in the mussel, Mytilus edulis.

Pollutants (e.g. PAHs, metals) cause oxidative stress (OS) by forming reactive oxygen species. Redox proteomics provides a means for identifying protein-specific OS effects in Mytilus edulis. Groups of mussels were sampled from a clean site in Cork Harbour, Ireland and exposed to 1 mM H2O2 in holding tanks. Protein extracts of gill and digestive gland were separated by two dimensional electrophoresis and similar protein expression profiles were found. Effects of OS on disulphide bridge patterns were investigated in diagonal gels by separating proteins in non-reducing conditions followed by a second reducing dimension. Immunoprecipitation selected carbonylated and glutathionylated proteins. These methodologies can contribute to redox proteomic studies of pollutant responses in marine organisms.

Two-dimensional electrophoresis analysis of glutathione affinity-selected proteins from the clam Tapes semidecussatus: Evidence for tissue-specific expression of redox proteins.

Proteins from gill, digestive gland and mantle of the clam Tapes semidecussatus were selected on glutathione (GSH) agarose to simplify proteomic comparison. Analysis by two-dimensional gel electrophoresis (2D SDS PAGE) revealed tissue-specific patterns of protein expression with some spots common to all tissues. Immunoblotting of gill and digestive gland separations identified some spots as glutathione transferases (GSTs). In gill and digestive gland several spots were immunoblotted with Pi class GSTs indicating multiple isoenzymes. Selected spots were excised, digested with trypsin and analyzed by reversed phase C-18 high performance liquid chromatography and tandem mass spectrometry. This confirmed that gill and digestive gland share some GST isoenzymes. Our results suggest that this clam expresses a complex tissue-specific pattern of GSH-binding proteins, which may reflect different redox requirements in each tissue.

Binge eating disorder in extreme obesity.

OBJECTIVE: To determine whether extremely obese binge eating disorder (BED) subjects (BED defined by the Eating Disorder Examination) differ from their extremely obese non-BED counterparts in terms of their eating disturbances, psychiatric morbidity and health status. DESIGN: Prospective clinical comparison of BED and non-BED subjects undergoing gastric bypass surgery (GBP). SUBJECTS: Thirty seven extremely obese (defined as BMI > or = 40 kg/m(2)) subjects (31 women, six men), aged 22-58 y. MEASUREMENTS: Eating Disorder Examination 12th Edition (EDE), Three Factor Eating Questionnaire (TFEQ), Structured Clinical Interview for the Diagnostic and Statistical Manual-IV (SCID-IV), Short-Form Health Status Survey (SF-36), and 24 h Feeding Paradigm. RESULTS: Twenty-five percent of subjects were classified as BED (11% met full and 14% partial BED criteria) and 75% of subjects were classified as non-BED. BED (full and partial) subjects had higher eating disturbance in terms of eating concern and shape concern (as found by the EDE), higher disinhibition (as found by the TFEQ), and they consumed more liquid meal during the 24 h feeding paradigm. No difference was found in psychiatric morbidity between BED and non-BED in terms of DSM-IV Axis I diagnosis. The health status scores of both BED and non-BED subjects were significantly lower than US norms on all subscales of the SF-36, particularly the BED group. CONCLUSION: Our findings support the validity of the category of BED within a population of extremely obese individuals before undergoing GBP. BED subjects differed from their non-BED counterparts in that they had a greater disturbance in eating attitudes and behavior, a poorer physical and mental health status, and a suggestion of impaired hunger/satiety control. However, in this population of extremely obese subjects, the stability of BED warrants further study.

Cognitive therapy, nutritional therapy and their combination in the treatment of bulimia nervosa.

BACKGROUND: This study compared the effectiveness of cognitive therapy (CT), nutritional therapy (NT), the combination of cognitive and nutritional therapy (CNT), against a control condition of support group (SG) in the treatment of bulimia nervosa. METHODS: One hundred female out-patients who fulfilled DSM-III-R criteria for bulimia nervosa were randomized to the four treatment groups. NT and CT were designed to cover different areas with minimal overlap, and CNT provided all of the features of both of these treatments. The control condition was conducted in a group self-help format. Each of the treatments lasted 14 weeks. RESULTS: All three active treatments as well as SG produced significant decreases in binge/vomit episodes. Intent-to-treat analysis found CNT and CT to be significantly more effective than SG in retaining subjects in treatment and completion of study, as well as in producing greater improvements in dysfunctional attitudes and self-control. CNT was superior to SG in achieving abstinence from bulimic behaviour. NT was superior to SG only in increase of self-control. Logistic regression found that the cognitive component, whether given alone or in conjunction with NT, and higher pre-treatment self-control scores were significant predictors for both completion of study and abstinence. CONCLUSION: CT (either alone, or in combination with nutritional therapy) remains the treatment of choice for bulimia nervosa. A treatment escalation approach should be tested for the treatment of bulimia with the more intensive and less widely available CT (with or without nutritional counselling) offered after patients have failed the less intensive and more widely available support group treatment.

Marking of resection margins.

Starch was used to mark the resection margins of breast tissue simply by rolling formalin fixed specimens in, for instance, glove powder. Starch adheres satisfactorily to the specimen and is obvious, microscopically, if crossed polarisers are used. There is little "carry-over" of starch across the rest of the tissue, and subsequent radiology of specimen or blocks is not prejudiced. It is concluded that starch powder is eminently suitable in most cases as a single marker of the surgically cut surface. The method is quick, cheap, and clean. It should not be relied on, anymore than other methods, to mark the surgically cut surface of ragged or partly disrupted specimens.

A computerized approach to statistical quality control for radioimmunoassays in the clinical chemistry laboratory.

Methods for statistical quality control for the clinical laboratory in general, and radioimmunoassay in particular, have been proposed for many years. Unfortunately, only a very small number of laboratories have adapted these procedures. By use of teletypes and other remote terminals, it is possible for all laboratories to access centralized computers where a general purpose quality control program can be stored. This relieves each laboratory of the costly task of developing software, provides some degree of inter-laboratory standardization and facilitates comparison of precision and accuracy between laboratories. A prototype program for this purpose is described. This program evaluates within-assay and between-assay variability, by means of an analysis of variance for a one-way classification random-effects model, and can monitor any assay parameter by use of control chart techniques. In addition, several tests are provided to evaluate the temporal stability of the assay system, and appropriate tests for outliers are included. Also, methods are described for combination of information from several quality control samples. This provides a valid basis for adjustment of assay results or for outright rejection of an assay. For convenience, this program is designed for output on a teletype or similar terminal located in the laboratory. Simplified versions of this program can be readily adapted to desk-top calculators. The original purpose for developing this system was to provide the clinical laboratory with a simple, general, and flexible method for assessing the performance of radioimmunoassays, but its usefulness should extend to virtually all assay methods.

The progression and evaluation of hetatologic and serum biochemical values in the chimpanzee.

Summary statistics of various hematologic and serum biochemical measures are presented for a colony of 74 chimpanzees (Pan troglodytes). Covariance analysis of longitudinal values revealed a progression of some measures with maturity. Equations for evaluating these measures as they relate to the health of individual colony members and new additions to the colony were formulated. From these equations, confidence bounds (95%), which can be regarded as normative ranges, were established for each of the measures. The literature on hematologic and serum biochemical values in the chimpanzee, especially as they pertain to the evaluation and progression of values, is reviewed.