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Carbohydrate Polymers Nov 2020Chitosan and chitin are categorized as low cost, renewable and eco-friendly biopolymers. However, they have low mechanical properties and unfavorable pore properties in...
Chitosan and chitin are categorized as low cost, renewable and eco-friendly biopolymers. However, they have low mechanical properties and unfavorable pore properties in terms of low surface area and total pore volume that limit their adsorption application. Many studies have shown that such weaknesses can be avoided by preparation of composites with carbonaceous materials from these biopolymers. This article provides a systematic review on the preparation of chitosan/chitin-carbonaceous material composites. Commonly used carbonaceous materials such as activated carbon, biochar, carbon nanotubes, graphene oxide and graphene to prepare composites are discussed. The application of chitosan/chitin-carbonaceous material composites for the adsorption of various water pollutants, and the regeneration and reusability of adsorbents are also included. Finally, the challenges and future prospects for the adsorbents applied for the adsorption of water pollutants are summarized.
Topics: Adsorption; Carbon; Chitin; Chitosan; Recycling; Water Pollutants, Chemical
PubMed: 32829818
DOI: 10.1016/j.carbpol.2020.116690 -
Critical Care (London, England) Nov 2016Major alterations in linezolid pharmacokinetic/pharmacodynamic (PK/PD) parameters might be expected in critically ill septic patients with acute kidney injury (AKI) who... (Review)
Review
BACKGROUND
Major alterations in linezolid pharmacokinetic/pharmacodynamic (PK/PD) parameters might be expected in critically ill septic patients with acute kidney injury (AKI) who are undergoing continuous renal replacement therapy (CRRT). The present review is aimed at describing extracorporeal removal of linezolid and the main PK-PD parameter changes observed in critically ill septic patients with AKI, who are on CRRT.
METHOD
Citations published on PubMed up to January 2016 were systematically reviewed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. All authors assessed the methodological quality of the studies and consensus was used to ensure studies met inclusion criteria. In-vivo studies in adult patients with AKI treated with linezolid and on CRRT were considered eligible for the analysis only if operational settings of the CRRT machine, membrane type, linezolid blood concentrations and main PK-PD parameters were all clearly reported.
RESULTS
Among 68 potentially relevant articles, only 9 were considered eligible for the analysis. Across these, 53 treatments were identified among the 49 patients included (46 treated with high-flux and 3 with high cut-off membranes). Continuous veno-venous hemofiltration (CVVH) was the most frequent treatment performed amongst the studies. The extracorporeal clearance values of linezolid across the different modalities were 1.2-2.3 L/h for CVVH, 0.9-2.2 L/h for hemodiafiltration and 2.3 L/h for hemodialysis, and large variability in PK/PD parameters was reported. The optimal area under the curve/minimum inhibitory concentration (AUC/MIC) ratio was reached for pathogens with an MIC of 4 mg/L in one study only.
CONCLUSIONS
Wide variability in linezolid PK/PD parameters has been observed across critically ill septic patients with AKI treated with CRRT. Particular attention should be paid to linezolid therapy in order to avoid antibiotic failure in these patients. Strategies to improve the effectiveness of this antimicrobial therapy (such as routine use of target drug monitoring, increased posology or extended infusion) should be carefully evaluated, both in clinical and research settings.
Topics: Acute Kidney Injury; Anti-Bacterial Agents; Critical Illness; Humans; Linezolid; Microbial Sensitivity Tests; Observational Studies as Topic; Prospective Studies; Renal Replacement Therapy
PubMed: 27863531
DOI: 10.1186/s13054-016-1551-7 -
Ancient Science of Life 2014Quality Ayurvedic herbal medicines are potential, low-cost solutions for addressing contemporary healthcare needs of both Indian and global community. Correlating... (Review)
Review
Quality Ayurvedic herbal medicines are potential, low-cost solutions for addressing contemporary healthcare needs of both Indian and global community. Correlating Ayurvedic herbal preparations with modern processing principles (MPPs) can help develop new and use appropriate technology for scaling up production of the medicines, which is necessary to meet the growing demand. Understanding the fundamental Ayurvedic principles behind formulation and processing is also important for improving the dosage forms. Even though Ayurvedic industry has adopted technologies from food, chemical and pharmaceutical industries, there is no systematic study to correlate the traditional and modern processing methods. This study is an attempt to provide a possible correlation between the Ayurvedic processing methods and MPPs. A systematic literature review was performed to identify the Ayurvedic processing methods by collecting information from English editions of classical Ayurveda texts on medicine preparation methods. Correlation between traditional and MPPs was done based on the techniques used in Ayurvedic drug processing. It was observed that in Ayurvedic medicine preparations there were two major types of processes, namely extraction, and separation. Extraction uses membrane rupturing and solute diffusion principles, while separation uses volatility, adsorption, and size-exclusion principles. The study provides systematic documentation of methods used in Ayurveda for herbal drug preparation along with its interpretation in terms of MPPs. This is the first step which can enable improving or replacing traditional techniques. New technologies or use of existing technologies can be used to improve the dosage forms and scaling up while maintaining the Ayurvedic principles similar to traditional techniques.
PubMed: 25737605
DOI: 10.4103/0257-7941.150768 -
Marine Drugs Jan 2015Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules... (Review)
Review
Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012-2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).
Topics: Adsorption; Chitosan; Coloring Agents; Cross-Linking Reagents; Environmental Restoration and Remediation; Metals; Microscopy, Electron, Scanning
PubMed: 25584681
DOI: 10.3390/md13010312 -
The Cochrane Database of Systematic... Oct 2014Chronic kidney disease (CKD) is a worldwide public health problem which is at high increased risk of cardiovascular disease (CVD) and renal failure. Deterioration of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Chronic kidney disease (CKD) is a worldwide public health problem which is at high increased risk of cardiovascular disease (CVD) and renal failure. Deterioration of kidney function causes an increase in circulating toxins, which, in turn promotes the progression of CKD. Oral adsorbents with capacity to adsorb and remove substances including uraemic toxins from the intestine could be effective in minimising kidney injury.
OBJECTIVES
To investigate the benefits and harms of oral adsorbents for preventing or delaying the progression of CKD.
SEARCH METHODS
We searched the Cochrane Renal Group's Specialised Register (to 22 September 2014) through contact with the Trials' Search Co-ordinator using search terms relevant to this review. The following four Chinese medical databases were also searched: China Biological Medicine Database (1979 to May 2012); Chinese Science and Technique Journals Database (to May 2012); China National Infrastructure (to May 2012); Wan Fang database (to May 2012).
SELECTION CRITERIA
Randomised controlled trials (RCTs) and quasi-RCTs comparing any oral adsorbents for preventing or delaying the progression of CKD.
DATA COLLECTION AND ANALYSIS
Two authors independently assessed and extracted information. Information was collected on methods, participants, interventions and outcomes (incidence of end-stage kidney disease (ESKD), mortality, quality of life and adverse events). Results were expressed as risk ratios (RR) for dichotomous outcomes or as mean differences (MD) for continuous data with 95% confidence intervals (CI). Adverse events were expressed as risk differences (RD).
MAIN RESULTS
Fifteen studies (1590 patients) conducted in Japan, China, and the USA were identified. The risk of bias of the included studies was moderate or high and the sample sizes were small.Three studies compared oral AST-120 plus routine treatment with placebo plus routine treatment; however data on our outcome measures of interest were not reported in two studies. These studies did not assess or did not provide data for our primary outcomes of interest (incidence of ESKD; time to ESKD; all-cause mortality). There was no significant difference in the changes of serum creatinine (SCr), slope of 1/SCr over time and creatinine clearance (CrCl) between AST-120 and placebo for patients with CKD.Eight studies compared oral AST-120 plus routine treatment with routine treatment alone; data on our outcome measures of interest were not reported in one study. There was no significant difference in incidence of ESKD, all-cause mortality and the change in health-related quality of life between AST-120 and routine treatment for patients with CKD. AST-120 showed beneficial effects on delaying the decline of kidney function measured by using the slope of change in estimated CrCl (SMD 0.39, 95% CI 0.21 to 0.5) and the mean changes of glomerular filtration rate (GFR) (MD -0.76 mL/min/mo, 95% CI -0.82 to -0.70) for patients with CKD; AST-120 was not superior to routine treatment in retarding the decline of kidney function measured by using the 1/SCr slope over time, occurrence of increase in SCr concentration, doubling of SCr concentration, changes in GFR from baseline (mL/min/1.73 m²) and slope of the eGFR curve (mL/min/mo) for patients with CKD.Three studies compared oral Ai Xi Te plus routine treatment with routine treatment alone. These studies did not assess our primary outcomes of interest. Compared with routine treatment, Ai Xi Te had positive effects on reducing SCr (MD -113.40 (µmol/L), 95% CI -188.69 to -38.10) and retarding the decline of CrCl (MD 9.74 (mL/min), 95% CI 4.28 to 15.21) for patients with CKD.One study compared oral Niaoduqing granules plus routine treatment with routine treatment alone, but did not assess our primary outcomes of interest. Compared with routine treatment, Niaoduqing granules had positive effects on reducing SCr (MD -135.60 (µmol/L), 95% CI -198.03 to -73.17) and CrCl (MD 13.30 (mL/min), 95% CI 5.69 to 20.91).The most commonly reported adverse events associated with AST-120 and Ai Xi Te were gastrointestinal symptoms however no serious adverse events were reported.
AUTHORS' CONCLUSIONS
Few studies reported our primary outcomes of interest. For our secondary outcomes, there is evidence of limited quality that AST-120, Ai Xi Te and Niaoduqing granules may have positive effects on delaying the decline of kidney function. There were no serious adverse events for any of the interventions in patients with CKD. Given the lack of information for our primary outcomes, the low methodological quality of most studies, and the small sample sizes, there is no strong evidence on the effectiveness of these oral adsorbents.
Topics: Administration, Oral; Adsorption; Carbon; Disease Progression; Humans; Oxides; Phytotherapy; Randomized Controlled Trials as Topic; Renal Insufficiency, Chronic
PubMed: 25317905
DOI: 10.1002/14651858.CD007861.pub2 -
Alimentary Pharmacology & Therapeutics Dec 2010Patients with ulcerative colitis (UC) that is chronically active despite 5-aminosalicylates or immunomodulators, or who are dependent on corticosteroids to maintain... (Review)
Review
BACKGROUND
Patients with ulcerative colitis (UC) that is chronically active despite 5-aminosalicylates or immunomodulators, or who are dependent on corticosteroids to maintain remission, have limited treatment options. Granulocyte/monocyte adsorptive apheresis (GMAA) may have a role in this situation.
AIM
To conduct a systematic review of GMAA in UC.
METHODS
MEDLINE, EMBASE and the Cochrane central register of controlled trials were searched to identify randomized controlled trials (RCTs) comparing GMAA with conventional medical therapy, sham procedure or 'intensive' with 'conventional' GMAA regimens in adult UC patients. Studies reported clinical remission or response rates.
RESULTS
Ten RCTs were eligible. Formal meta-analysis was not undertaken due to concerns about methodological quality of identified studies. Compared with medical therapy, remission rates with GMAA were generally higher, and corticosteroid-sparing effects were observed. Compared with sham procedure, GMAA did not achieve significantly higher remission rates. 'Intensive' GMAA regimens demonstrated generally higher remission rates, and time to remission was shorter compared with 'conventional' regimens. Only two RCTs were at low risk of bias. Six were conducted in Japanese patients, which may limit generalizability.
CONCLUSIONS
Granulocyte/monocyte adsorptive apheresis appears of some benefit in UC. High-quality RCTs comparing granulocyte/monocyte adsorptive apheresis with conventional medical therapy or sham procedure in Western populations, with disease activity confirmed endoscopically, are required.
Topics: Adsorption; Blood Component Removal; Chronic Disease; Colitis, Ulcerative; Granulocytes; Humans; Monocytes; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 21050231
DOI: 10.1111/j.1365-2036.2010.04490.x -
Critical Care (London, England) 2007Severe sepsis and septic shock are common problems in the intensive care unit and carry a high mortality. Endotoxin, one of the principal components on the outer... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Severe sepsis and septic shock are common problems in the intensive care unit and carry a high mortality. Endotoxin, one of the principal components on the outer membrane of gram-negative bacteria, is considered important to their pathogenesis. Polymyxin B bound and immobilized to polystyrene fibers (PMX-F) is a medical device that aims to remove circulating endotoxin by adsorption, theoretically preventing the progression of the biological cascade of sepsis. We performed a systematic review to describe the effect in septic patients of direct hemoperfusion with PMX-F on outcomes of blood pressure, use of vasoactive drugs, oxygenation, and mortality reported in published studies.
METHODS
We searched PubMed, the Cochrane Collaboration Database, and bibliographies of retrieved articles and consulted with experts to identify relevant studies. Prospective and retrospective observational studies, pre- and post-intervention design, and randomized controlled trials were included. Three authors reviewed all citations. We identified a total of 28 publications - 9 randomized controlled trials, 7 non-randomized parallel studies, and 12 pre-post design studies - that reported at least one of the specified outcome measures (pooled sample size, 1,425 patients: 978 PMX-F and 447 conventional medical therapy).
RESULTS
Overall, mean arterial pressure (MAP) increased by 19 mm Hg (95% confidence interval [CI], 15 to 22 mm Hg; p < 0.001), representing a 26% mean increase in MAP (range, 14% to 42%), whereas dopamine/dobutamine dose decreased by 1.8 microg/kg per minute (95% CI, 0.4 to 3.3 microg/kg per minute; p = 0.01) after PMX-F. There was significant intertrial heterogeneity for these outcomes (p < 0.001), which became non-significant when analysis was stratified for baseline MAP. The mean arterial partial pressure of oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio increased by 32 units (95% CI, 23 to 41 units; p < 0.001). PMX-F therapy was associated with significantly lower mortality risk (risk ratio, 0.53; 95% CI, 0.43 to 0.65). The trials assessed had suboptimal method quality.
CONCLUSION
Based on this critical review of the published literature, direct hemoperfusion with PMX-F appears to have favorable effects on MAP, dopamine use, PaO2/FiO2 ratio, and mortality. However, publication bias and lack of blinding need to be considered. These findings support the need for further rigorous study of this therapy.
Topics: Adult; Aged; Cardiotonic Agents; Dobutamine; Dopamine; Endotoxins; Hemoperfusion; Humans; Middle Aged; Polymyxin B; Sepsis; Survival Rate; Treatment Outcome
PubMed: 17448226
DOI: 10.1186/cc5780