Acid-catalyzed hydrolysis of cellulose and cellulosic waste using a microwave reactor system

A microwave reactor system was investigated as a potential technique to maximize sugar yield for the hydrolysis of municipal solid waste for ethanol production. Specifically, dilute acid hydrolysis of a-cellulose and waste cellulosic biomass (grass clippings) with phosphoric acid was undertaken within the microwave reactor system. The experimental data and reaction kinetic analysis indicate that the use of a microwave reactor system can successfully facilitate dilute acid hydrolysis of cellulose and waste cellulosic biomass, producing high yields of total sugars in short reaction times. The maximum yield of reducing sugars was obtained at 7.5% (w/v) phosphoric acid and 160 degrees C, corresponding to 60% of the theoretical total sugars, with a reaction time of 5 min. When using a very low acid concentration (0.4% w/v) for the hydrolysis in the microwave reactor, it was found that 10 g of total sugars/100 g dry mass was produced, which is significant considering the low acid concentration. When hydrolyzing grass clippings using the microwave reactor, the optimum conditions were an acid concentration of 2.5% (w/v), 175 degrees C with a 15 min reaction time, giving 18 g/100 g dry mass of total sugars, with xylose being the sugar with the highest yield. It was observed that pentose sugars were more easily formed but also more easily degraded, these being significantly affected by increases in acid concentration and temperature. Kinetic modeling of the data indicated that the use of microwave heating may account for an increase in reaction rate constant, k(1), found in this study in comparison with conventional systems described in the literature.

Glycemic index, carbohydrate and fiber intakes and risk of reflux esophagitis, Barrett’s esophagus, and esophageal adenocarcinoma

Objective: To examine the association between dietary glycemic index (GI), glycemic load (GL), total carbohydrate, sugars, starch, and fiber intakes and the risk of reflux esophagitis, Barrett’s esophagus, and esophageal adenocarcinoma.

Methods: In an all-Ireland study, dietary information was collected from patients with esophageal adenocarcinoma (n = 224), long-segment Barrett’s esophagus (n = 220), reflux esophagitis (n = 219), and population-based controls (n = 256). Multiple logistic regression analysis examined the association between dietary variables and disease risk by tertiles of intake and as continuous variables, while adjusting for potential confounders.

Results: Reflux esophagitis risk was positively associated with starch intake and negatively associated with sugar intake. Barrett’s esophagus risk was significantly reduced in people in the highest versus the lowest tertile of fiber intake (OR 0.44 95%CI 0.25–0.80). Fiber intake was also associated with a reduced risk of esophageal adenocarcinoma, as was total carbohydrate intake (OR 0.45 95%CI 0.33–0.61 per 50 g/d increase). However, an increased esophageal adenocarcinoma risk was detected per 10 unit increase in GI intake (OR 1.42 95%CI 1.07–1.89).

Conclusions: Our findings suggest that fiber intake is inversely associated with Barrett’s esophagus and esophageal adenocarcinoma risk. Esophageal adenocarcinoma risk is inversely associated with total carbohydrate consumption but positively associated with high GI intakes.

Advanced glycation end products (AGEs) co-localize with AGE receptors in the retinal vasculature of diabetic and of AGE-infused rats

Advanced glycation end products (AGEs), formed from the nonenzymatic glycation of proteins and lipids with reducing sugars, have been implicated in many diabetic complications; however, their role in diabetic retinopathy remains largely unknown. Recent studies suggest that the cellular actions of AGEs may be mediated by AGE-specific receptors (AGE-R). We have examined the immunolocalization of AGEs and AGE-R components R1 and R2 in the retinal vasculature at 2, 4, and 8 months after STZ-induced diabetes as well as in nondiabetic rats infused with AGE bovine serum albumin for 2 weeks. Using polyclonal or monoclonal anti-AGE antibodies and polyclonal antibodies to recombinant AGE-R1 and AGE-R2, immunoreactivity (IR) was examined in the complete retinal vascular tree after isolation by trypsin digestion. After 2, 4, and 8 months of diabetes, there was a gradual increase in AGE IR in basement membrane. At 8 months, pericytes, smooth muscle cells, and endothelial cells of the retinal vessels showed dense intracellular AGE IR. AGE epitopes stained most intensely within pericytes and smooth muscle cells but less in basement membrane of AGE-infused rats compared with the diabetic group. Retinas from normal or bovine-serum-albumin-infused rats were largely negative for AGE IR. AGE-R1 and -R2 co-localized strongly with AGEs of vascular endothelial cells, pericytes, and smooth muscle cells of either normal, diabetic, or AGE-infused rat retinas, and this distribution did not vary with each condition. The data indicate that AGEs accumulate as a function of diabetes duration first within the basement membrane and then intracellularly, co-localizing with cellular AGE-Rs. Significant AGE deposits appear within the pericytes after long-term diabetes or acute challenge with AGE infusion conditions associated with pericyte damage. Co-localization of AGEs and AGE-Rs in retinal cells points to possible interactions of pathogenic significance.

Increased levels of advanced glycation endproducts in the lenses and blood vessels of cigarette smokers.

BACKGROUND: Advanced glycation endproducts (AGEs) arise from the spontaneous reaction of reducing sugars with the amino groups of macromolecules. AGEs accumulate in tissue as a consequence of diabetes and aging and have been causally implicated in the pathogenesis of several of the end-organ complications of diabetes and aging, including cataract, atherosclerosis, and renal insufficiency. It has been recently proposed that components in mainstream cigarette smoke can react with plasma and extracellular matrix proteins to form covalent adducts with many of the properties of AGEs. We wished to ascertain whether AGEs or immunochemically related molecules are present at higher levels in the tissues of smokers.

MATERIALS AND METHODS: Lens and coronary artery specimens from nondiabetic smokers and nondiabetic nonsmokers were examined by immunohistochemistry, immunoelectron microscopy, and ELISA employing several distinct anti-AGE antibodies. In addition, lenticular extracts were tested for AGE-associated fluorescence by fluorescence spectroscopy.

RESULTS: Immunoreactive AGEs were present at significantly higher levels in the lenses and lenticular extracts of nondiabetic smokers (p < 0.003). Anti-AGE immunogold staining was diffusely distributed throughout lens fiber cells. AGE-associated fluorescence was significantly increased in the lenticular extracts of nondiabetic smokers (p = 0.005). AGE-immunoreactivity was significantly elevated in coronary arteries from nondiabetic smokers compared with nondiabetic nonsmokers (p = 0.015).

CONCLUSIONS: AGEs or immunochemically related molecules are present at higher levels in the tissues of smokers than in nonsmokers, irrespective of diabetes. In view of previous reports implicating AGEs in a causal association with numerous pathologies, these findings have significant ramifications for understanding the etiopathology of diseases associated with smoking, the single greatest preventable cause of morbidity and mortality in the United States.

Quantification of N-(glucitol)ethanolamine and N-(carboxymethyl)serine:two products of nonenzymatic modification of aminophospholipids formed in vivo

Chemical, nonenzymatic modification of protein and lipids by reducing sugars, such as glucose, is thought to contribute to age-related deterioration in tissue protein and cellular membranes and to the pathogenesis of diabetic complications. This report describes the synthesis and quantification of N-(glucitol)ethanolamine (GE) and N-(carboxymethyl)serine (CMS), two products of nonenzymatic modification of aminophospholipids. GE is the product of reduction and hydrolysis of glycated phosphatidylethanolamine (PE), while CMS is formed through reaction of phosphatidylserine (PS) with products of oxidation of either carbohydrate (glycoxidation) or lipids (lipoxidation). Gas chromatography/mass spectrometry procedures for quantification of the N,O-acetyl methyl ester derivatives of the modified head groups were developed. GE and CMS were quantified in samples of PE and PS, respectively, following incubation with glucose in vitro; CMS formation was dependent on the presence of oxygen during the incubation. Both GE and CMS were detected and quantified in lipid extracts of human red blood cell membranes. The content of GE, but not CMS, was increased in the lipids from diabetic compared to nondiabetic subjects. Measurement of these modified lipids should prove useful for assessing the role of carbonyl-amine reactions of aminophospholipids in aging and age-related diseases.

The Maillard reaction in vivo

The Maillard or browning reaction between reducing sugars and protein contributes to the chemical deterioration and loss of nutritional value of proteins during food processing and storage. This article presents and discusses evidence that the Maillard reaction is also involved in the chemical aging of long-lived proteins in human tissues. While the concentration of the Amadori adduct of glucose to lens protein and skin collagen is relatively constant with age, products of sequential glycation and oxidation of protein, termed glycoxidation products, accumulate in these long-lived proteins with advancing age and at an accelerated rate in diabetes. Among these products are the chemically modified amino acids, N epsilon-(carboxymethyl)lysine (CML), N epsilon-(carboxymethyl)hydroxylysine (CMhL), and the fluorescent crosslink, pentosidine. While these glycoxidation products are present at only trace levels in tissue proteins, there is strong evidence for the presence of other browning products which remain to be characterized. Mechanisms for detoxifying reactive intermediates in the Maillard reaction and catabolism of extensively browned proteins are also discussed, along with recent approaches for therapeutic modulation of advanced stages of the Maillard reaction.

Post-slaughter changes in ATP metabolites, Reducing and phosphorylated sugars in chicken meat

The formation of ATP breakdown products in chicken M. pectoralis major post-slaughter is reported. The concentrations of metabolites were followed in chicken breast throughout the carcass processing post-slaughter and during chilled storage. The concentration of glucose remains similar throughout the period whilst that of glucose-6-phosphate decreases linearly. Glucose and glucose-6-phosphate concentrations were inversely related to the pHu of the breast meat throughout chilled storage. Rapid post-mortem glycolysis and high pHu values suggest the occurrence of stress at and pre-slaughter. Whilst ATP, ADP and AMP were rapidly broken down, the concentration of IMP rose rapidly and remained high. Concentrations of inosine, ribose and hypoxanthine increased gradually post-slaughter but an initial increase in ribose phosphate was not sustained. Most of the potential ribose present in chicken meat, believed to be important for flavor formation, remains bound in the form of inosine and IMP. There is evidence that additional breakdown pathways for ribose and ribose-5-phosphate may deplete the concentrations of these precursors.

Effect of pH and temperature on the formation of volatile compounds in cysteine/reducing sugar/starch mixtures during extrusion cooking

Mixtures of cysteine, reducing sugar (xylose or glucose), and starch were extrusion cooked using feed pH values of 5.5, 6.5, and 7.5 and target die temperatures of 120, 150, and 180 degreesC. Volatile compounds were isolated by headspace trapping onto Tenax and analyzed by gas chromatography-mass spectrometry. Eighty and 38 compounds, respectively, were identified from extrudates prepared using glucose and xylose. Amounts of most compounds increased with temperature and pH. Aliphatic sulfur compounds, thiophenes, pyrazines, and thiazoles were the most abundant chemical classes for the glucose samples, whereas for xylose extrudates highest levels were obtained for non-sulfur-containing furans, thiophenes, sulfur-containing furans, and pyrazines. 2-Furanmethanethiol and 2-methyl-3-furanthiol were present in extrudates prepared using both sugars, but levels were higher in xylose samples. The profiles of reaction products were different from those obtained from aqueous or reduced-moisture systems based on cysteine and either glucose or ribose.

Use of weaning protocols for reducing duration of mechanical ventilation in critically ill adult patients: Cochrane systematic review and meta-analysis.

Objective To investigate the effects of weaning protocols on the total duration of mechanical ventilation, mortality, adverse events, quality of life, weaning duration, and length of stay in the intensive care unit and hospital.

Design Systematic review.

Data sources Cochrane Central Register of Controlled Trials, Medline, Embase, CINAHL, LILACS, ISI Web of Science, ISI Conference Proceedings, Cambridge Scientific Abstracts, and reference lists of articles. We did not apply language restrictions.

Review methods We included randomised and quasi-randomised controlled trials of weaning from mechanical ventilation with and without protocols in critically ill adults.

Data selection Three authors independently assessed trial quality and extracted data. A priori subgroup and sensitivity analyses were performed. We contacted study authors for additional information.

Results Eleven trials that included 1971 patients met the inclusion criteria. Compared with usual care, the geometric mean duration of mechanical ventilation in the weaning protocol group was reduced by 25% (95% confidence interval 9% to 39%, P=0.006; 10 trials); the duration of weaning was reduced by 78% (31% to 93%, P=0.009; six trials); and stay in the intensive care unit length by 10% (2% to 19%, P=0.02; eight trials). There was significant heterogeneity among studies for total duration of mechanical ventilation (I(2)=76%, P

Conclusion There is evidence of a reduction in the duration of mechanical ventilation, weaning, and stay in the intensive care unit when standardised weaning protocols are used, but there is significant heterogeneity among studies and an insufficient number of studies to investigate the source of this heterogeneity. Some studies suggest that organisational context could influence outcomes, but this could not be evaluated as it was outside the scope of this review.

Protocolized versus non-protocolized weaning for reducing the duration of invasive mechanical ventilation in critically ill paediatric patients (Protocol)

This is the protocol for a review and there is no abstract. The objectives are as follows:

To assess the effects of weaning by protocol for invasively ventilated critically ill children.

To compare the total duration of invasive mechanical ventilation of critically ill children who are weaned using protocols versus usual (non-protocolized) practice.
To ascertain any differences between protocolized weaning and usual care in terms of mortality, adverse events, ICU length of stay, and quality of life.

Restorative justice conferencing for reducing recidivism in young offenders (aged 7 to 21)

Background
Restorative justice is “a process whereby parties with a stake in a specific offence resolve collectively how to deal with the aftermath of the offence and its implications for the future” (Marshall 2003). Despite the increasing use of restorative justice programmes as an alternative to court proceedings, no systematic review has been undertaken of the available evidence on the effectiveness of these programmes with young offenders. Recidivism in young offenders is a particularly worrying problem, as recent surveys have indicated
the frequency of re-offences for young offenders has ranged from 40.2% in 2000 to 37.8% in 2007 (Ministry of Justice 2009)

Objectives
To evaluate the effects of restorative justice conferencing programmes for reducing recidivism in young offenders.

Search methods
We searched the following databases up to May 2012: CENTRAL, 2012 Issue 5, MEDLINE (1978 to current), Bibliography of Nordic Criminology (1999 to current), Index to Theses (1716 to current), PsycINFO (1887 to current), Social Sciences Citation Index (1970 to current), Sociological Abstracts (1952 to current), Social Care Online (1985 to current), Restorative Justice Online (1975 to current), Scopus (1823 to current), Science Direct (1823 to current), LILACS (1982 to current), ERIC (1966 to current), Restorative Justice Online (4May 2012),WorldCat (9May 2012), ClinicalTrials.gov (19May 2012) and ICTRP (19May 2012). ASSIA,National Criminal Justice Reference Service and Social Services Abstracts were searched up to May 2011. Relevant bibliographies, conference programmes and journals were also searched.

Selection criteria
Randomised controlled trials (RCTs) or quasi-RCTs of restorative justice conferencing versus management as usual, in young offenders.

Data collection and analysis
Two authors independently assessed the risk of bias of included trials and extracted the data. Where necessary, original investigators were contacted to obtain missing information.

Main results
Four trials including a total of 1447 young offenders were included in the review. Results failed to find a significant effect for restorative justice conferencing over normal court procedures for any of the main analyses, including number re-arrested (odds ratio (OR) 1.00, 95% confidence interval (CI) 0.59 to 1.71; P = 0.99), monthly rate of reoffending (standardised mean difference (SMD) -0.06, 95% CI -0.28 to 0.16; P = 0.61), young person’s remorse following conference (OR 1.73, 95% CI 0.97 to 3.10; P = 0.06), young person’s recognition of wrongdoing following conference (OR 1.97, 95% CI 0.81 to 4.80; P = 0.14), young person’s self-perception following conference (OR 0.95, 95% CI 0.55 to 1.63; P = 0.85), young person’s satisfaction following conference (OR 0.42, 95% CI 0.04 to 4.07; P = 0.45) and victim’s satisfaction following conference (OR 4.05, 95%CI 0.56 to 29.04; P = 0.16). A small number of sensitivity analyses did indicate significant effects, although all are to be interpreted with caution.

Authors’ conclusions
There is currently a lack of high quality evidence regarding the effectiveness of restorative justice conferencing for young offenders. Caution is urged in interpreting the results of this review considering the small number of included studies, subsequent low power and high risk of bias. The effects may potentially be more evident for victims than offenders. The need for further research in this area is highlighted.

Identification of low inorganic and total grain arsenic rice cultivars from Bangladesh

For the world's population, rice consumption is a major source of inorganic arsenic (As), a nonthreshold class 1 carcinogen. Reducing the amount of total and inorganic As within the rice grain would reduce the exposure risk. In this study, grain As was measured in 76 cultivars consisting of Bangladeshi landraces, improved Bangladesh Rice Research Institute (BRRI) cultivars, and parents of permanent mapping populations grown in two field sites in Bangladesh, Faridpur and Sonargaon, irrigated with As-contaminated tubewell water. Grain As ranged from 0.16 to 0.74 mg kg(-1) at Faridpur and from 0.07 to 0.28 mg kg(-1) at Sonargaon. Highly significant cultivar differences were detected and a significant correlation (r = 0.802) in the grain As between the two field sites was observed, indicating stable genetic differences in As accumulation. The cultivars with the highest concentration of grain As were the Bangladeshi landraces. Landraces with red bran had significantly more grain As than the cultivars with brown bran. The percent of inorganic As decreased linearly with increasing total As, but genetic variation within this trend was identified. A number of local cultivars with low grain As were identified. Some tropical japonica cultivars with low grain As have the potential to be used in breeding programs and genetic studies aiming to identify genes which decrease grain As.

Hydrolysis characteristics and kinetics of waste hay biomass as a potential energy crop for fermentable sugars production using autoclave parr reactor system

The use of the organic fraction of municipal solid waste crops has received considerable attention as a sustainable feedstock that can replace fossil fuels for the production of renewable energy. Therefore, municipal bin-waste in the form of hay was investigated as a potential energy crop for fermentable sugars production. Hydrolysis of hay by dilute phosphoric acid was carried out in autoclave parr reactor, where reactor temperature (135-200 degrees c) and acid concentration (2.5-10% (w/w)) were examined. Analysis of the decomposition rate of hemicellulosic biomass was undertaken using HPLC of the reaction products. Xylose production reached a maximum value of 13.5 g/100 g dry mass corresponding to a yield of 67% at the best identified conditions of 2.5 wt% H3PO4, 175 degrees C, 10 min reaction time, and at 5 wt% H3PO4, 150 degrees C, and 5 min reaction time. For glucose, an average yield of 25% was obtained at 5 wt% H3PO4, 175 degrees C and 30 min. Glucose degradation to HMF was achieved at 10 wt% H3PO4 and 200 degrees C. The maximum yield for produced arabinose was an average of 3 g/100 g dry. mass corresponding to 100% of the total possible arabinose. The kinetic study of the acid hydrolysis was also carried out using the Saeman and the Two-fraction models. It was found for both models that the kinetic constants (k) depend on the acid concentration and temperature. For xylose and arabinose it was found that the rate of formation was more favoured than the rate of degradation. By contrast, for glucose it was found that glucose degradation was occurring faster than glucose formation. It can be concluded that dilute phosphoric acid hydrolysis of hay crop is feasible for the production of fermentable sugars which are essential for bioethanol synthesis. 

Reducing the psychological distress of family caregivers of home-based palliative care patients: short-term effects from a randomised controlled trial

BACKGROUND: Palliative care is expected to incorporate comprehensive support for family caregivers given that many caregivers suffer psychological morbidity. However, systematically implemented evidence-based psychological support initiatives are lacking.
AIM: The objective of this study was to prepare caregivers for the role of supporting a patient with advanced cancer receiving home-based palliative care by offering a one-to-one psycho-educational intervention. We hypothesised that primary family caregivers who participated in the intervention would report decreased psychological distress (primary outcome), fewer unmet needs and increased levels of perceived preparedness, competence and positive emotions.
METHODS: A three-arm randomised controlled trial was conducted comparing two versions of the intervention (one face-to-face visit versus two visits) plus standard care to a control group (standard care) across four sites in Australia.
RESULTS: A total of 298 participants were recruited; 148 were in the Control condition, 57 in Intervention 1 (one visit) and 93 in Intervention 2 (two visits). Relative to participants in the control group; the psychological well-being of participants in the intervention condition was improved by a small amount but non-significantly. No significant reduction in unmet needs or improvements in positive aspects of caregiving amongst the intervention group were identified. However, the intervention demonstrated significant improvements in participants' levels of preparedness and competence for Intervention 2.
CONCLUSION/IMPLICATIONS: This research adds to accumulating body of evidence demonstrating that relatively short psycho-educational interventions can enable family caregivers to feel more prepared and competent in the role of supporting a dying relative. Further investigation is required to determine the longer term outcomes of such interventions. 

Protocolized versus non-protocolized weaning for reducing the duration of mechanical ventilation in critically ill adult patients (Review)

BACKGROUND: Reducing weaning time is desirable in minimizing potential complications from mechanical ventilation. Standardized weaning protocols are purported to reduce time spent on mechanical ventilation. However, evidence supporting their use in clinical practice is inconsistent.

OBJECTIVES: To assess the effects of protocolized weaning from mechanical ventilation on the total duration of mechanical ventilation for critically ill adults; ascertain differences between protocolized and non-protocolized weaning in terms of mortality, adverse events, quality of life, weaning duration, intensive care unit (ICU) and hospital length of stay (LOS); and explore variation in outcomes by type of ICU, type of protocol and approach to delivering the protocol.

SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2010), MEDLINE (1950 to 2010), EMBASE (1988 to 2010), CINAHL (1937 to 2010), LILACS (1982 to 2010), ISI Web of Science and ISI Conference Proceedings (1970 to 2010), Cambridge Scientific Abstracts (inception to 2010) and reference lists of articles. We did not apply language restrictions.

SELECTION CRITERIA: We included randomized and quasi-randomized controlled trials of protocolized weaning versus non-protocolized weaning from mechanical ventilation in critically ill adults.

DATA COLLECTION AND ANALYSIS: Three authors independently assessed trial quality and extracted data. A priori subgroup and sensitivity analyses were performed. We contacted study authors for additional information.

MAIN RESULTS: Eleven trials that included 1971 patients met the inclusion criteria. The total duration of mechanical ventilation geometric mean in the protocolized weaning group was on average reduced by 25% compared with the usual care group (N = 10 trials, 95% CI 9% to 39%, P = 0.006); weaning duration was reduced by 78% (N = 6 trials, 95% CI 31% to 93%, P = 0.009); and ICU LOS by 10% (N = 8 trials, 95% CI 2% to 19%, P = 0.02). There was significant heterogeneity among studies for total duration of mechanical ventilation (I(2) = 76%, P <0.01) and weaning duration (I(2) = 97%, P <0.01), which could not be explained by subgroup analyses based on type of unit or type of approach.

AUTHORS' CONCLUSIONS: There is some evidence of a reduction in the duration of mechanical ventilation, weaning duration and ICU LOS with use of standardized protocols, but there is significant heterogeneity among studies and an insufficient number of studies to investigate the source of this heterogeneity. Although some study authors suggest that organizational context may influence outcomes, these factors were not considered in all included studies and therefore could not be evaluated.