Advanced search options

Advanced Search Options 🞨

Browse by author name (“Author name starts with…”).

Find ETDs with:

in
/  
in
/  
in
/  
in

Written in Published in Earliest date Latest date

Sorted by

Results per page:

Sorted by: relevance · author · university · dateNew search

You searched for subject:(Enterosorption). Showing records 1 – 3 of 3 total matches.

Search Limiters

Last 2 Years | English Only

No search limiters apply to these results.

▼ Search Limiters


Texas A&M University

1. Mitchell, Nicole Jean. Human Exposure to Foodborne Toxins in Ghana: Intervention Strategy for Reduction of Aflatoxin and Fumonisin Bioavailability.

Degree: PhD, Toxicology, 2013, Texas A&M University

International health has typically focused on remediation of infectious diseases in developing countries. However, recent reports from the International Agency for Research on Cancer (IARC) have highlighted the importance of cancer incidence/ mortality in the developing world. Foodborne mycotoxins produced by fungi, called aflatoxin (AF) and fumonisin (FB), have been associated with hepatocellular and esophageal carcinomas among other deleterious effects, such as growth faltering and immune dysfunction. Exposure to these toxins in Ghana is particularly high due to food insecurity, climate, and lack of regulatory infrastructures. Work to alleviate AF and FB contamination in Africa has focused on instituting good agricultural and storage practices however, exposures remain inextricable in many communities. Utilization of a calcium montmorillonite clay, UPSN, shows promise of tightly binding both AF and FB in the gastrointestinal tract, thereby reducing their bioavailability. The objectives of this research were to determine exposure susceptibility in Ghana and to assess efficacy and safety of UPSN treatment within vulnerable populations. Cross-sectional data from six different regions of Ghana indicated that AF exposure is associated with maize consumption and region of residence. However, food preparation practices were not correlated to AF levels in the present study. Therefore, future intervention strategies were focused on the end point of the food consumption chain by reducing AF exposure from maize immediately prior to ingestion (i.e. UPSN treatment). In a three-month trial an encapsulated montmorillonite clay was efficacious in reducing AF exposure. However, concern for sustainability and its applicability for children led to an effort to alter the dose dissemination form. Inclusion of UPSN in common Ghanaian foods retained the efficacy of the clay, reducing a short-term biomarker (AFM_(1)) by 55%, and was determined to be safe in children (ages 3-9). Importantly, daily assessment of AFM_(1) levels was successful in providing statistical significance of intervention effects within only five days of treatment. Initial results indicate that UPSN could efficiently to bind both AF and FB in the gastrointestinal tract, reducing biomarkers for both toxins in animal models. Thus, UPSN could positively impact health in developing communities at risk for AF and FB exposure. Advisors/Committee Members: Phillips, Timothy D (advisor), Porter, Weston W (committee member), Safe, Stephen H (committee member), Welsh, Jane C (committee member).

Subjects/Keywords: Aflatoxin; Fumonisin; Bioavailability; NovaSil clay; Enterosorption

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Mitchell, N. J. (2013). Human Exposure to Foodborne Toxins in Ghana: Intervention Strategy for Reduction of Aflatoxin and Fumonisin Bioavailability. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151665

Chicago Manual of Style (16th Edition):

Mitchell, Nicole Jean. “Human Exposure to Foodborne Toxins in Ghana: Intervention Strategy for Reduction of Aflatoxin and Fumonisin Bioavailability.” 2013. Doctoral Dissertation, Texas A&M University. Accessed November 29, 2020. http://hdl.handle.net/1969.1/151665.

MLA Handbook (7th Edition):

Mitchell, Nicole Jean. “Human Exposure to Foodborne Toxins in Ghana: Intervention Strategy for Reduction of Aflatoxin and Fumonisin Bioavailability.” 2013. Web. 29 Nov 2020.

Vancouver:

Mitchell NJ. Human Exposure to Foodborne Toxins in Ghana: Intervention Strategy for Reduction of Aflatoxin and Fumonisin Bioavailability. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2020 Nov 29]. Available from: http://hdl.handle.net/1969.1/151665.

Council of Science Editors:

Mitchell NJ. Human Exposure to Foodborne Toxins in Ghana: Intervention Strategy for Reduction of Aflatoxin and Fumonisin Bioavailability. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151665

2. Taylor, John Floyd. Ferrihydrite as an Enterosorbent for Arsenic.

Degree: PhD, Toxicology, 2012, Texas A&M University

Arsenic in drinking water is a problem in many developing nations such as Taiwan and Bangladesh. Currently, no oral binding agent exists for the mitigation of arsenic toxicity. The goals of this research were to 1) screen a variety of sorbents for their ability to sorb As from water and screen for potential nutrient interactions with vitamin A (VA) and riboflavin (RF) isotherms; 2) further describe the sorption of As to ferrihydrite using isothermal analysis and a simulated gastrointestinal model (GI), and by testing ferrihydrite’s ability to protect Hydra from As toxicity; 3) verify ferrihydrite’s safety and efficacy in a short term rodent model. Ferrihydrite was found to be the most effective sorbent for both As(III) and As(V). Exchanging SWy-2 with sulfur containing organic groups increased the sorption of both As(V) and As(III) compared to the parent clay, though the total As sorbed was much less than As sorption by ferrihydrite. Ferrihydrite and an industrially produced ferrihydrite (IPF) both sorbed As(V) and As(III) with high capacity. Both ferrihydrites also sorbed As(V) and As(III) at high capacity in the simulated GI model. Fe measured in the simulated GI tract was below tolerable daily limits for both ferrihydrite and IPF. Ferrihydrite at 0.25 percent w/w was found to protect Hydra up to 200 times the minimal effective concentration (MEC) for As(III) and over 2.5 times the MEC for As(V), while IPF at 0.25 percent w/w protected Hydra up to 200 times the MEC for As(III) and just over 2 times the MEC for As(V). IPF was apparently safe and well tolerated by the rats in our study over a period of 2 weeks. No statistically significant differences were seen in serum biochemistry, serum Fe, serum VA, or serum vitamin E between rats fed control diet versus those fed 0.5 percent w/w IPF. Ferrihydrite was found to reduce urinary As after a single gavage of 0.5 mL of 500 ppm As(III) or As(V). These results verify in vitro findings and suggest that ferrihydrite is apparently safe and effective as an enterosorbent for As. Advisors/Committee Members: Phillips, Timothy D. (advisor), Hallmark, Charles T. (committee member), Porter, Weston W. (committee member), Welsh, Christabel J. (committee member).

Subjects/Keywords: Arsenic; Enterosorption; ferrihydrite

Enterosorption Therapy for Aflatoxin ................................... Dietary Iron Requirements and… 

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Taylor, J. F. (2012). Ferrihydrite as an Enterosorbent for Arsenic. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8852

Chicago Manual of Style (16th Edition):

Taylor, John Floyd. “Ferrihydrite as an Enterosorbent for Arsenic.” 2012. Doctoral Dissertation, Texas A&M University. Accessed November 29, 2020. http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8852.

MLA Handbook (7th Edition):

Taylor, John Floyd. “Ferrihydrite as an Enterosorbent for Arsenic.” 2012. Web. 29 Nov 2020.

Vancouver:

Taylor JF. Ferrihydrite as an Enterosorbent for Arsenic. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2020 Nov 29]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8852.

Council of Science Editors:

Taylor JF. Ferrihydrite as an Enterosorbent for Arsenic. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8852


Texas A&M University

3. Elmore, Sarah Elizabeth. Aflatoxin and Fumonisin Exposure: International Survey and Enterosorption Mitigation Strategy in Humans.

Degree: PhD, Toxicology, 2016, Texas A&M University

Aflatoxins (AFs) are toxic metabolites produced by Aspergillus flavus and A. parasiticus. Fumonisins (FBs) are also toxic products of fungi, specifically Fusarium verticilloides and F. proliferatum. Both toxins commonly contaminate staple grains and cereals such as maize and groundnuts. Aflatoxin B1 (AFB1) is the most toxic and prevalent of the AFs. Chronic dietary exposure to AFs is a known risk factor for hepatocellular carcinoma and may also affect protein metabolism and the immune system. Fumonisin B1 (FB1) is the most abundant and toxicologically significant of the congeners. In populations where AFs and FBs are inextricable contaminants, a multi-faceted approach must be implemented to reduce exposure to these toxins, especially in the young who are more susceptible. Alternative methods such as calcium montmorillonite clay (UPSN or ACCS100) as an enterosorbent therapy that focus on reducing biological exposure to AFs and FBs in foods already contaminated are desirable as a secondary defense to the harmful effects of these toxins. Therefore, I propose to test the efficacy of UPSN in food matrices, identify populations at high risk for AFs and FBs with urinary biomarkers, and finally, combine clay technology and biomarker analysis to intervene with UPSN or ACCS100 in frequently exposed human populations. In these studies UPSN was able to significantly reduce AFB1 under common cooking conditions in a corn meal matrix suggesting a potential delivery of the clay directly in the contaminated food. A high prevalence of exposure to variable AFB1 and FB1 levels in participants from Monterrey, Mexico was observed. After a two week crossover trial in a high risk area of Kenya with 3.0g ACCS100/day mixed in water, urinary aflatoxin M1 (an AFB1 metabolite) was significantly reduced compared to the placebo group. ACCS100 was found to be safe and well tolerated suggesting potential for reducing exposure to AF in this particular population during outbreak situations. In a 3-month intervention with 3.0g or 1.5g ACCS100/day (encapsulated) in San Antonio, Texas, AFB1-lysine (an AFB1 protein adduct) was significantly reduced in the Low Dose group (1.5g) compared to Placebo. ACCS100 was well tolerated in the majority of participants and no significant changes in serum biochemistry or hematology were detected in any treatment group. Thus, use of calcium montmorillonite clay at doses as low as 1.5g/day and delivered in capsules, food, drink, or water may provide a viable strategy to reduce dietary AFB1 bioavailability in populations exposed to this toxin for up to 3 months. Moreover, AF and FB exposure is a global and unavoidable public health concern and biomarkers are important tools for monitoring exposure. Advisors/Committee Members: Phillips, Timothy D. (advisor), Harvey, Roger B. (committee member), Safe, Stephen H. (committee member), Villalobos, Alice R.A. (committee member).

Subjects/Keywords: Aflatoxin; Fumonisin; Calcium Montmorillonite Clay; ACCS100; UPSN; Enterosorption; Clay Mitigation Therapy; Biomarkers Of Exposure

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Elmore, S. E. (2016). Aflatoxin and Fumonisin Exposure: International Survey and Enterosorption Mitigation Strategy in Humans. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/157053

Chicago Manual of Style (16th Edition):

Elmore, Sarah Elizabeth. “Aflatoxin and Fumonisin Exposure: International Survey and Enterosorption Mitigation Strategy in Humans.” 2016. Doctoral Dissertation, Texas A&M University. Accessed November 29, 2020. http://hdl.handle.net/1969.1/157053.

MLA Handbook (7th Edition):

Elmore, Sarah Elizabeth. “Aflatoxin and Fumonisin Exposure: International Survey and Enterosorption Mitigation Strategy in Humans.” 2016. Web. 29 Nov 2020.

Vancouver:

Elmore SE. Aflatoxin and Fumonisin Exposure: International Survey and Enterosorption Mitigation Strategy in Humans. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2020 Nov 29]. Available from: http://hdl.handle.net/1969.1/157053.

Council of Science Editors:

Elmore SE. Aflatoxin and Fumonisin Exposure: International Survey and Enterosorption Mitigation Strategy in Humans. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/157053

.