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Understanding the mechanism of toxicity of carbon nanoparticles in humans in the new millennium: A systemic review  [cached]
Sharma Mukesh
Indian Journal of Occupational and Environmental Medicine , 2010,
Abstract: Manmade nanoparticles range from the well-established multi-ton production of carbon black and fumed silica for applications in plastic fillers and car tyres to microgram quantities of fluorescent quantum dots used as markers in biological imaging. While benefits of nanotechnology are widely publicized, the discussion of the potential effects of their widespread use in the consumer and industrial products are just beginning to emerge. Acceptance of nanoparticle toxicity led to wide acceptance of the fact that nanotoxicology, as a scientific discipline shall be quite different from occupational hygiene in approach and context. Understanding the toxicity of nanomaterials and nano-enabled products is important for human and environmental health and safety as well as public acceptance. Assessing the state of knowledge about nanotoxicology is an important step in promoting comprehensive understanding of the health and environmental implications of these new materials. Very limited data exist for health effects secondary to inhalation of very fine respirable particles in the occupational environment. Nanomaterials may have effects on health due to their size, surface, shape, charge, or other factors, which are not directly predictable from mass concentration measurements. Numerous epidemiological studies have associated exposure to small particles such as combustion-generated fine particles with lung cancer, heart disease, asthma and/or increased mortality. The omnipresence of nanoparticles shifts focus of research toward efforts to mitigate the health effects of nanoparticles. Newer health assessment methods and newer techniques need to be developed for diagnosing sub-optimal health in populations exposed to carbon nanoparticles.
MYTHS AND FACTS ABOUT ASPARTAME AND SUCRALOSE: A CRITICAL REVIEW  [PDF]
Maganti Brahmini,Tanikonda Keerthi,Birudugadda Priyadarshini,Idpuganti Sudheerbabu
International Journal of Research in Ayurveda and Pharmacy , 2012,
Abstract: Earlier, a clinical research gave a clean chit to the artificial sweeteners, dismissing allegations that these sweeteners induce certain ailments. Aspartame has been found to be safe for human consumption by more than ninety countries worldwide, with FDA officials describing aspartame as “one of the most thoroughly tested and studied food additives the agency have ever approved” and its safety as “clearcut”. The dangers of aspartame are now widely known, but the risks of using sucralose are not documented-until now. When deciding between sucralose and aspartame, it is important to remember that studies conclude that both are safe when consumed with in reasonable limits.However, some consumers reported symptoms which were believed to be associated with these sweeteners. When FDA probed in to the matter, it came with the conclusion that there is no enough medical evidence that suggests a link between these sweeteners and alleged illnesses. Thus, it can be deduced that artificial sweeteners can be safely consumed in moderate doses.
Metabolic Effects of Sucralose on Environmental Bacteria  [PDF]
Arthur Omran,Gregory Ahearn,Doria Bowers,Janice Swenson,Charles Coughlin
Journal of Toxicology , 2013, DOI: 10.1155/2013/372986
Abstract: Sucralose was developed as a low cost artificial sweetener that is nonmetabolizable in humans. Sucralose can withstand changes in pH and temperature and is not degraded by the wastewater treatment process. Since the molecule can withstand heat, acidification, and microbial degradation, it is accumulating in the environment and has been found in wastewater, estuaries, rivers, and the Gulf Stream. Environmental isolates were cultured in the presence of sucralose looking for potential sucralose metabolism or growth acceleration responses. Sucralose was found to be nonnutritive and demonstrated bacteriostatic effects on all six isolates. This growth inhibition was directly proportional to the concentration of sucralose exposure, and the amount of the growth inhibition appeared to be species-specific. The bacteriostatic effect may be due to a decrease in sucrose uptake by bacteria exposed to sucralose. We have determined that sucralose inhibits invertase and sucrose permease. These enzymes cannot catalyze hydrolysis or be effective in transmembrane transport of the sugar substitute. Current environmental concentrations should not have much of an effect on environmental bacteria since the bacteriostatic effect seems to be consecration based; however, as sucralose accumulates in the environment, we must consider it a contaminant, especially for microenvironments. 1. Introduction Sucralose was the first noncalorie sweetener made from natural sugar, being manufactured by the selective chlorination of sucrose, which substitutes three of the hydroxyl groups with chlorines [1]. Sucralose is stable under increased heat and over a broad range of acidic and alkaline conditions. Therefore, sucralose can be used in baking or in products that require a longer shelf-life [2]. Sucralose causes exactly zero caloric increase in mammals [1]. Artificial sweeteners have been considered contaminants by environmental scientists only recently [3]. Due to the human inability to metabolize these molecules, they are passed on to the environment via human excrement, and the highest concentration (2,800 ± 1,000?ng/L) of combined artificial sweetener contaminants is found in wastewater treatment reservoirs [4]. Artificial sweeteners such as saccharin and cyclamates are found mostly degraded by the wastewater treatment process. Sucralose, however, is found in higher concentrations and was degraded minimally [4]. Degradation only occurs to a limited extent during hydrolysis, ozonation, and microbial processes indicating that breakdown of sucralose will likely be slow and incomplete
Synthesis of Strong Sweetener Sucralose  [cached]
Ye Luo,Lei Xu,Xiaofei Sun
Modern Applied Science , 2009, DOI: 10.5539/mas.v2n3p13
Abstract: Synthesize sucralose from sucrose as a starting material by following steps: first synthesis sucrose-6-acetate, and then by chlorination, at last deacetylation. The Synthetic Approach is simple, with high yield and under mild reaction conditions. the ultimate product sucralose was purified and bleaching, and its structure was characterized by the IR, MS, etc.
CONTAMINATION OF MERCURY IN FISH AND ITS TOXICITY TO BOTH FISH AND HUMANS: AN OVERVIEW  [PDF]
Govind Pandey,Madhuri S.,A.B. Shrivastav
International Research Journal of Pharmacy , 2012,
Abstract: Heavy metals are considered the most important form of pollution of the aquatic environment because of their toxicity and accumulation by marine organisms. The fish may be more greatly affected by anthropogenic pollution sources. Fish are highly exposed from the heavy metals, like mercury (Hg), leading to severe toxicity, both in the fish and human beings. The fish accumulate substantial concentrations of Hg in their tissues, and thus the fish are the single largest sources of Hg for humans through fish eating. The organic forms of Hg (e.g., methyl Hg) are more toxic than the inorganic forms due to ease of absorption into the human system. Communities that relied on fish intake for daily nutrient sustenance may be at risk from chronic, high exposure to methyl Hg, as well as other persistent organic environmental pollutants. The organic Hg compounds are most toxic to central nervous system (CNS), and may also affect the kidneys and immune system. The main symptoms of Hg poisoning in humans include kidney damage, disruption of nervous system, damage to brain functions, DNA and chromosomal damage, allergic reactions, sperm damage, birth defects, and miscarriages. The greater concern for Hg exposure is not to adult human, but to developing foetus. The methyl Hg content of fish varies by species and size of the fish as well as harvest location. The FDA level of concern for Hg in fish is 1 ppm. The fish with levels higher than this should probably be avoided by everyone.
Biological Effect of Sucralose in Diabetic Rats  [PDF]
Helen N. Saada, Nefissa H. Mekky, Hassan A. Eldawy, Abeer F. Abdelaal
Food and Nutrition Sciences (FNS) , 2013, DOI: 10.4236/fns.2013.47A010
Abstract: Among people that might take a large amount of sucralose, are diabetic people who are attempting to modify their carbohydrate intake. The objective of this study is to evaluate the impact of sucralose; an artificial sweetener derived from sucrose, at a dose approximately twice the ADI on hyperglycemia, hyperlipidemia and oxidative stress in diabetic rats. Diabetes was induced in male albino rats after an intraperitoneal streptozotocin injection (65 mg/kg body weight). Animals with fasting blood glucose levels ≥250 mg/dl were considered diabetics. Sucralose was dissolved in water and administered to rats daily by oral gavages during a period of 6 weeks at a dose of 11 mg/kg body weight. Animals were divided into 4 groups and treated in parallel for 6 weeks. Control: rats received distilled water, Sucralose: rats received sucralose, Diabetic: diabetic rats received distilled water, Diabeticrats + Sucralose: diabetic rats received sucralose. The administration of sucralose to diabetic rats provoked a significant decrease (P < 0.05) of serum glucose and triglyceride levels, a significant increase (P < 0.05) of total cholesterol, low density lipoprotein-cholesterol (LDL-C), and high density lipoprotein-cholesterol (HDL-C), while has no effect (P > 0.05) on insulin, compared to their respective values in diabetic rats receiving distilled water. Biochemical analysis in brain and testis tissues showed that sucralose has no effect (P > 0.05) on superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px), and glucose-6-phosphate dehydrogenase (G-6-PDH) activities, and glutathione content (GSH), while reduced thiobarbituric acid reactive substances level (TBARS) (P < 0.05), compared to their respective values in diabetic rats receiving distilled water. It could be concluded that consumption of sucralose didn’t induce oxidative stress, has no effect on insulin, reduce glucose absorption and intensify hypercholesterolemia in STZ-induced diabetic rats. Accordingly it is advised that diabetic people consuming high amount of sucralose must check their lipid profile to avoid diabetic complications.
Probiotics in humans – evidence based review
Harish K,Varghese T
Calicut Medical Journal , 2006,
Abstract: Probiotics are live microbial food supplements or components ofbacteria, which have been shown to have beneficial effects onhuman health. They are perceived to exert such effects bychanging the composition of the gut microbiota. Several probioticpreparations seem to have promise in prevention or treatment ofvarious conditions. There currently exists good evidence for thetherapeutic use of probiotics in infectious diarrhea in children,recurrent Clostridium difficile induced infections and postoperativepouchitis. The possible benefit in other gastrointestinal infections,prevention of postoperative bacterial translocation, irritable bowelsyndrome and inflammatory bowel disease continues to emerge.This review addresses the concept of probiotics and evidence fromhuman clinical trials regarding the possible uses of probiotics inclinical practice.
Collective Intelligence in Humans: A Literature Review  [PDF]
Juho Salminen
Computer Science , 2012,
Abstract: This literature review focuses on collective intelligence in humans. A keyword search was performed on the Web of Knowledge and selected papers were reviewed in order to reveal themes relevant to collective intelligence. Three levels of abstraction were identified in discussion about the phenomenon: the micro-level, the macro-level and the level of emergence. Recurring themes in the literature were categorized under the above-mentioned framework and directions for future research were identified.
Thermal stability and thermal decomposition of sucralose
Bannach, Gilbert;Almeida, Rafael R.;Lacerda, Luis. G.;Schnitzler, Egon;Ionashiro, Massao;
Eclética Química , 2009, DOI: 10.1590/S0100-46702009000400002
Abstract: several papers have been described on the thermal stability of the sweetener, c12h19cl3o8 (sucralose). nevertheless no study using thermoanalytical techniques was found in the literature. simultaneous thermogravimetry and differential thermal analysis (tg-dta), differential scanning calorimetry (dsc) and infrared spectroscopy, have been used to study the thermal stability and thermal decomposition of sweetener.
A review of Dichlorvos toxicity in fish  [cached]
SUCHISMITA DAS
Current World Environment , 2013, DOI: 10.12944/cwe.8.1.08
Abstract: Among the wide majority of pesticides, dichlorvos (2, 2-dichlorovinyl dimethyl phosphate), a organophosphate compound, is commonly used as agricultural insecticide. It is extremely toxic to non target organisms like fish and hampers fish health through impairment of metabolism, sometimes leading to death. As one of the few organophosphates still registered for use, dichlorvos has elicited worldwide concern for many reasons. This study is a review of potential adverse effects of dichlorvos in fish
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