Immunomodulatory dietary polysaccharides: a systematic review of the literature

Background

A large body of literature suggests that certain polysaccharides affect immune system function. Much of this literature, however, consists of in vitro studies or studies in which polysaccharides were injected. Their immunologic effects following oral administration is less clear. The purpose of this systematic review was to consolidate and evaluate the available data regarding the specific immunologic effects of dietary polysaccharides.

Methods

Studies were identified by conducting PubMed and Google Scholar electronic searches and through reviews of polysaccharide article bibliographies. Only articles published in English were included in this review. Two researchers reviewed data on study design, control, sample size, results, and nature of outcome measures. Subsequent searches were conducted to gather information about polysaccharide safety, structure and composition, and disposition.

Results

We found 62 publications reporting statistically significant effects of orally ingested glucans, pectins, heteroglycans, glucomannans, fucoidans, galactomannans, arabinogalactans and mixed polysaccharide products in rodents. Fifteen controlled human studies reported that oral glucans, arabinogalactans, heteroglycans, and fucoidans exerted significant effects. Although some studies investigated anti-inflammatory effects, most studies investigated the ability of oral polysaccharides to stimulate the immune system. These studies, as well as safety and toxicity studies, suggest that these polysaccharide products appear to be largely well-tolerated.

Conclusions

Taken as a whole, the oral polysaccharide literature is highly heterogenous and is not sufficient to support broad product structure/function generalizations. Numerous dietary polysaccharides, particularly glucans, appear to elicit diverse immunomodulatory effects in numerous animal tissues, including the blood, GI tract and spleen. Glucan extracts from the Trametes versicolor mushroom improved survival and immune function in human RCTs of cancer patients; glucans, arabinogalactans and fucoidans elicited immunomodulatory effects in controlled studies of healthy adults and patients with canker sores and seasonal allergies. This review provides a foundation that can serve to guide future research on immune modulation by well-characterized polysaccharide compounds.     

Triggers for chemical product design: A systematic literature review

The product design project is a complex problem because objectives and constraints must be considered simultaneously, the sustainability context is highly relevant and specific, decision-making involves not only customer needs but also of other stakeholders, especially the organization in which the design project takes place. This work presents a systematic literature review of design methodologies for chemical products to identify how that problem has been addressed and which are the future challenges to be met. The review involved the analysis of 262 research papers and 336 patents, classified according to the chemical product type, the design phase studied, and whether they consider association with a business context. The study highlights the need for holistic product design methodologies applicable from the early design stages, covering the assessment of customer needs and the requirements of other stakeholders, as well as the business context where the design process is carried out.     

CO2 capture using membrane contactors: a systematic literature review

With fossil fuel being the major source of energy, CO₂ emission levels need to be reduced to a minimal amount namely from anthropogenic sources. Energy consumption is expected to rise by 48% in the next 30 years, and global warming is becoming an alarming issue which needs to be addressed on a thorough technical basis. Nonetheless, exploring CO₂ capture using membrane contactor technology has shown great potential to be applied and utilised by industry to deal with post- and pre-combustion of CO₂. A systematic review of the literature has been conducted to analyse and assess CO₂ removal using membrane contactors for capturing techniques in industrial processes. The review began with a total of 2650 papers, which were obtained from three major databases, and then were excluded down to a final number of 525 papers following a defined set of criteria. The results showed that the use of hollow fibre membranes have demonstrated popularity, as well as the use of amine solvents for CO₂ removal. This current systematic review in CO₂ removal and capture is an important milestone in the synthesis of up to date research with the potential to serve as a benchmark databank for further research in similar areas of work. This study provides the first systematic enquiry in the evidence to research further sustainable methods to capture and separate CO₂.     

Different types of bioceramics as dental pulp capping materials: A systematic review

The aim of this study was to summarize and systemically review the different types of bioceramics that have been proposed to be used as direct dental pulp capping materials for dentin regeneration in permanent teeth. This article reviewed the studies carried out on the bioceramic materials as dental pulp capping agents. PubMed, Embase, Cochrane Central Register of Controlled Trials, and Scopus electronic databases were searched with the selected keywords. The retrieved articles were evaluated by 2 reviewers according to the inclusion and exclusion criteria and the extracted data were arranged in Tables. After removing duplicate articles and further screening, 3126 articles were retrieved in this review. Following discussing the composition and characteristics of different types of bioceramics reported in the literature, 47 articles that met the inclusion criteria were included in this systematic review. The results of this review showed that certain types of calcium silicate-based materials, mineral trioxide aggregate (MTA), and Biodentine seem to be the most effective bioceramics currently used for direct pulp capping in permanent teeth compared with that of other types of bioceramics. In addition, different types of calcium phosphate materials like tricalcium phosphates and bioactive glasses have been recently introduced as alternative bioceramics for dental pulp capping. Calcium phosphates might be considered as more appropriate pulp capping materials in future because of their unique characteristics. However, because of lack of promising information, only further well-designed in vitro and long term clinical studies are required to confirm the most appropriate type of bioceramics for direct dental pulp capping procedures.     

Photopolymerization-based additive manufacturing of ceramics:A systematic review

Conversion of inorganic-organic frameworks (ceramic precursors and ceramic-polymer mixtures) into solid mass ceramic structures based on photopolymerization pro...     

Chromatic interior environments for the elderly: A literature review

The impact of the physical environment on individuals has arisen as a growing body of research in population wellbeing. Yet, most of studies in this area do not focus on elderly even though they are particularly susceptible to the characteristics of their interior spaces. It is a well‐known fact that to be old is to acquire a tolerance of disabilities based on the gradual degeneration. A common problem is a dysfunction in visual sensitivity and accordingly, the alteration of their environmental color perception. That is why these impairments need to be understood in order to minimize the elderly spatial difficulties. To know at what point there is a loss in the ability to perceive color is necessary to understand how should we take these facts into consideration. A state‐of‐the‐art literature review of current studies from the last 20 years is carried out. The aim is to analyze existing practices on Evidence‐Based Research through a multidisciplinary approach in order to create knowledge about chromatic built environments for the elderly. Data are identified and considered together with empirical experience about color, perception, built environment and elderly. Thus, the way in which elderly perceive the space is explored. The adjustments in the formulation of these impairments throughout any design strategy to adapt the environment to their physiological changes are determined. This article aims to determine a design interpretation of the various findings, demonstrating that color, as a parameter of the visual performance, influences visual comfort and helps performance in architecture for old people.     

Scalability of biomass-derived graphene derivative materials as viable anode electrode for a commercialized microbial fuel cell: A systematic review

Microbial fuel cell(MFC) is an advanced bioelectrochemical technique that can utilize biomass materials in the process of simultaneously generating electricity and biodegrading or bio transforming toxic pollutants from wastewater. The overall performance of the system is largely dependent on the efficiency of the anode electrode to enhance electron transportation. Furthermore, the anode electrode has a significant impact on the overall cost of MFC setup. Hence, the need to explore research focus...     

Effects of dietetic supplementation with L-arginine in cancer patients. A review of the literature

It has been suggested that the administration of certain nutrients may improve the immune response of patients with cancer. Experimental studies have shown that deficiencies in specific amino acids have a worse effect on humoral immunity than they do on cell-mediated immunity because they impair antibody synthesis. Here, arginine plays a particularly important role, and research with several experimental and human tumor models to determine the therapeutic utility of this amino acid is under way. In this paper, we review current literature on the use of arginine as pharmacologic nutritional support for cancer patients. Dietary supplementation with arginine has been shown to benefit these patients by reducing the growth of transplantable tumors, the incidence of metastases, and the tumor-producing potential of carcinogens. However, results observed in humans have given rise to controversy regarding the optimal dosage of arginine supplementation and the types of cancer best treated with amino acids. Further prospective and randomized studies will be necessary in order to determine the proper utilization and the therapeutic benefits of such dietary supplementation.     

竹红菌甲素与牛血清白蛋白相互作用光谱研究

利用紫外-可见（UV—Vis）吸收光谱和荧光光谱研究在生理pH值条件下,竹红菌甲素（Hypocre-llin A,HA）与牛血清白蛋白（BSA）的相互作用。UV—Vis吸收光谱中HA的吸收峰蓝移,表明HA的存在使BSA分子中的氨基酸残基形成氢键。荧光光谱结果表明,BSA的存在对于HA的荧光发射峰具有一定的影响。双分子猝灭速率常数为1．65×10^12L·（mol·s）^-1,表明HA与BSA相互作用发生在HA与BSA分子外部的氨基酸残基之间,与BSA分子内部结构没有直接的相互作用。     

Salt effect in distillation: A literature review II

A salt dissolved in a mixed solvent is capable, through preferential association or other structure-related effects in the liquid phase, of altering the composition of the equilibrium vapor phase. Hence salt effect on vapor-liquid equilibrium relationships provides a potential technique of extractive distillation for difficult separations. The literature pertaining to salt effect in vapor-liquid equilibrium and in extractive distillation over the period 1966-present is reviewed, and also the remainder of work up to 1966 not covered in the Part I review.     

A spectroscopic study of the interaction of nigerloxin,a fungal metabolite,with serum albumin

Nigerloxin [2-amido-3-hydroxy-6-methoxy-5-methyl-4-(prop-1′-enyl) benzoic acid], a fungal metabolite, is an inhibitor of lipoxygenase and aldose reductase with free radical-scavenging properties. The interaction of nigerloxin with bovine serum albumin (BSA) was investigated using fluorescence spectroscopy and circular dichroic measurements. The fluorescence of BSA was quenched following interaction with nigerloxin, and this property was used to generate a binding constant. The estimated association constant was 1.01±0.2×10⁶ M⁻¹. Job's method of continuous variation indicated that nigerloxin formed a 1∶1±0.1 complex with BSA. To understand the nature of the interaction, the variance in the association constant as a function of temperature in the range of 14–45°C was used to calculate the thermodynamic parameters. The thermodynamic parameters at 27°C derived from the mass action plot and van't Hoff's plot were as follows: ΔG=−8.2±0.1 kcal/mol, ΔH≈0 kcal/mol, and ΔS=27.5±0.4 cal/mol/K (where ΔG is free energy, ΔH is enthalpy, and ΔS is entropy). Increasing ionic strength did not favor interaction. Circular dichroic measurements revealed that the interaction of nigerloxin with BSA did not lead to changes in the secondary structure of the protein. The reversibility of the interaction verified by the dilution method was found to be reversible. These measurements suggest that partial hydrophobic and partial ionic bonding play a role in the interaction of nigerloxin with BSA.     

Crystal structure of human serum albumin at 2.5 A resolution

A new triclinic crystal form of human serum albumin (HSA), derivedeither from pool plasma (pHSA) or from a Pichia pastoris expressionsystem (rHSA), was obtained from polyethylene glycol 4000 solution.Three-dimensional structures of pHSA and rHSA were determinedat 2.5 Å resolution from the new triclinic crystal formby molecular replacement, using atomic coordinates derived froma multiple isomorphous replacement work with a known tetragonalcrystal form. The structures of pHSA and rHSA are virtuallyidentical, with an r.m.s. deviation of 0.24 Å for allC atoms. The two HSA molecules involved in the asymmetric unitare related by a strict local twofold symmetry such that theC atoms of the two molecules can be superimposed with an r.m.s.deviation of 0.28 Å in pHSA. Cys34 is the only cysteinewith a free sulfhydryl group which does not participate in adisulfide linkage with any external ligand. Domains II and IIIboth have a pocket formed mostly of hydrophobic and positivelycharged residues and in which a very wide range of compoundsmay be accommodated. Three tentative binding sites for long-chainfatty acids, each with different surroundings, are located atthe surface of each domain.     

Bovine serum albumin as chain transfer agent in the acrylamide polymerization. Protein-polymer conjugates

Acrylamide photopolymerization at 25 °C, using as chain transfer agent the single exposed cysteine residue of bovine serum albumin (BSA), resulted in a conjugate where a single poly(acrylamide) chain is bound to the cysteine residue of the protein. Studies of the intrinsic fluorescence of the protein and of the extrinsic probe, 1-anilino-8-naphthalene-sulfonic acid, indicate that the protein mostly maintains its native structure in the conjugate. Kinetic studies showed that the chain transfer efficiency of thiols depends on the microenvironment where the -SH group is located. The single exposed cysteine residue of BSA is a more efficient chain transfer agent of the acrylamide polymerization than the free cysteine or glutathione tripeptide. Other potentially reactive amino acids, such as tryptophan, tyrosine and histidine, are two orders of magnitude less efficient than the protein as chain transfer agents.     

Bonding of adhesive resin to intraradicular dentine: A review of the literature

Bonding to intraradicular dentine is widely practiced by modern dentists, both in general as well as specialist practices. Materials, such as resin-based root canal sealers and resin cements, are routinely used in endodontic treatment, like root canal obturation and luting fiber post for post and core restorations. Though bonding to intraradicular dentine in principle is the same as bonding to coronal dentine, there are several structural differences between coronal and intraradicular dentine substrates. Also, the consequences of pulpal necrosis and subsequent endodontic therapy could alter the intraradicular dentine substrate significantly, which would have an impact on intraradicular dentine bonding. Therefore, this comprehensive review was performed from the published literature retrieved from “Pubmed” database using specific keywords “root, “dentine”, “resin”, and “bonding”. The relevant articles were selected after screening the title and abstracts. Further relevant articles included in this review were identified from the reference lists of the originally retrieved articles. In this review, we have narrated the various aspects of bonding to intraradicular root dentine. Successful bonding to intraradicular dentine depends on proper understanding of this unique bonding substrate.     

Nylons: A review of the literature on products of combustion and toxicity

The literature on polyamides was reviewed to determine the nature and extent of information available on these materials which are commonly used in consumer and industrial applications. This review was limited to aliphatic polyamides normally called nylon and excludes aromatic polyamides such as Nomex and bicomponent polymers consisting of nylon and other polymers. The review was further limited to those publications in English through June 1984. Typical pyrolysis products from a broad range of nylons do not appear to differ greatly. Many of the decomposition products detected in vacuum pyrolysis experiments appear as products of thermal degradation in inert and air atmospheres. In air, a general reduction in the quantities of heavier hydrocarbons is noted along with an increase in the production of CO, CO₂, H₂O, NH₃, HCN and NO_x. The toxicity of the thermal degradation products from various types of nylon has been evaluated by nine different protocols. Reported LC₅₀ values range from 10.8 m l^?1 to 61.9 mg l^?1. Dyes apparently do not affect the materials' combustion products toxicity but an increase in the amount of backcoating on a nylon fabric increases toxicity. Time to death measurements show that volatile products from nylons are less toxic than those from rayons or cotton, while the blending of wool with nylon greatly increases the toxicity of the thermal decomposition products. In general, however, the overall toxicity of the thermal degradation products from nylon do not appear to be greatly different than those from many other polymeric materials. Large-scale test results are ambiguous, and it is difficult to interpret the results in terms of a single component in a multicomponent system.     

Natural history as a predictor of protein evolvability

Natural selection generally produces specific and efficient enzymes. In contrast, directed evolution experiments usually produce enzyme variants with broadened substrate specificity or enhanced catalytic promiscuity. Some proteins may be more evolvable than others, but few workers consider this problem when choosing starting points for laboratory evolution. Here, we review the variables associated with enzyme evolvability, namely promiscuity and mutational robustness. We present a qualitative model of adaptive evolution and recommend that protein engineers exploit their knowledge of natural history to identify evolvable wild-type proteins. Three examples of 'generalist' proteins that evolved in the laboratory into 'specialists' are described to illustrate the practical utility of this point.     

Nitrification inhibitors in agriculture and horticulture: A literature review

Preface This literature survey is the English version of P. Kerkhoff and J.H.G. Slangen Nitrificatieremstoffen in Land- en Tuinbouw, Interne Mededeling 54, Vakgroep Bodemkunde en Bemestingsleer, Landbouwhogeschool, Wageningen, 99 p, 1980, supplemented by reference to the literature of 1980 and a partly of 1981. The literature cited has been taken from sources in East and West Europe and North America.Only crops common in the regions mentioned are involved. For this reason rice has not been included in the cereals. Aspects of controlling the nitrogen status in soils by, for instance, controlled release fertilizers are not discussed and no details of the effects of pesticides on the NO₃ - and or NH₄ - contents in soils are given here.This review of literature is focussed on the readily available nitrification inhibitors N Serve (2-chloro-6-(trichloromethylpyridine), DCD (dicyandiamide) and AM (2-amino-4-chloro-6-methylpyrimidine). Compounds such as Terrazole (5-ethoxy-3-trichloromethyl-1,2,4-thiadiazole), DCS (N-2,5-dichloro-phenyl-succinamic acid) and non synthetic inhibitors like Neem and Karanjin are only briefly discussed.Some chemical characteristics of these inhibitors are summarized. The effects of such soil characteristics as texture, organic matter content, pH moisture content, O₂-pressure and temperature on their efficiency are being discussed. These aspects are seen in relation to yield and to the chemical composition of a number of agricultural (wheat, maize, grassland, oats) and horticultural (lettuce, spinach, tomatoes) crops.Phytotoxicity, residual effects and residues in soils and plants of the most interesting compounds are reviewed as well as aspects of some effects of inhibitors on plant diseases.Most of the compounds are more or less effective in keeping nitrogen in the NH₄-form thus leading to a relatively high content of NH₄-N over a shorter or longer period. In a number of situations this leads to more effective use of nitrogen, but not necessarily to higher yields. This increase of nitrogen efficiency can be explained by a decrease in leaching and or denitrification of nitrogen. Lower NO₃-contents in vegetables, found in some of the experiments with nitrification inhibitors, cannot be used to declare the products as generally useful in this respect. The uptake and assimilation of nitrogen by plants in their overall diversity cannot be regulated by adding a simple compound to the soil, not even in small quantities.     

Aging of oily soils on textile materials: A literature review

Literature covering the problems of oily soil aging on textile materials is reviewed. Difficulty of soil removal and discoloration of oily soiled fabrics were the main problems of aged oily soil reported by researchers. Yellowing of fabrics is attributed mainly to residual oily soils although there are other causes. Oxidation of unsaturated oils was suggested as the cause of problems related to aging of oily soils; thus, the autoxidation mechanisms of unsaturated lipids are an important part of this review. The effects of aging on oily soil removal are attributed to this oxidation of unsaturated oils, wicking of oils into small capillaries within the yarn structure, and possible chemical linkages of aged oils with fibers. Thus, included in this review are studies on the interactions between lipid oxidation products and proteins that suggest interaction between aged oily soils and fiber substrates.     

On the mechanism of hydrogen evolution catalysis by proteins: A case study with bovine serum albumin

The catalysis of the hydrogen evolution reaction (HER) by proteins has been known for decades but was only recently found to be useful for electroanalytical purposes. The mechanism of the catalytic process is investigated at hanging mercury drop electrodes by cyclic voltammetry, with bovine serum albumin as a model system. It is shown that the catalyst is the protein in the adsorbed state. The influence of various parameters such as the accumulation time, scan rate or buffer concentration is studied, and interpreted in the framework of a surface catalytic mechanism. Under the experimental conditions used in the work, a “total catalysis” phenomenon takes place, the rate of HER being limited by the diffusion of the proton donor. The adequacy of the existing models is discussed, leading to a call for the development of more refined models.