Sylvia Daunert - Academia.edu (original) (raw)

Papers by Sylvia Daunert

Gastroenterology, May 1, 2009

preparations were seen in 82.4% and 80.3% in Study 1 and 97.2% and 95.6% in Study 2 for the oral ... more preparations were seen in 82.4% and 80.3% in Study 1 and 97.2% and 95.6% in Study 2 for the oral sulfate solution and the PEG-EA regimen, respectively. Split dose administration resulted in more excellent preparations in the sulfate group than in the PEG-EA group (63.3% vs 52.5%, P=0.043), and a higher mean preparation score (3.59 to 3.47, respectively, P=0.05). Preparation related symptoms of cramping, bloating, nausea and vomiting were generally mild and infrequent. Sulfate subjects reported slightly increased gastrointestinal events and higher vomiting scores (p = 0.009) in the one day preparation but not in the split dose regimen. There were no other differences for adverse events or clinically significant laboratory findings including creatinine. Conclusion: The new 960ml oral sulfate solution is effective for colonoscopy cleansing and has an acceptable safety profile. Split-dose administration provided additional efficacy and tolerance.

Molecular Pharmaceutics, May 4, 2022

Journal of Fluorescence, Sep 1, 2004

The importance of glucose monitoring for in vivo as well as for ex vivo applications has driven a... more The importance of glucose monitoring for in vivo as well as for ex vivo applications has driven a vast number of scientific groups to pursue the development of an advanced glucose sensor. Such a sensor must be robust, versatile, and capable of the long-term, accurate and reproducible detection of glucose levels in various testing media. Among the different configurations and signal transduction mechanisms used, fluorescence-based glucose sensors constitute a growing class of glucose sensors represented by an increasing number of significant contributions to the field over the last few years. This manuscript reviews the progress in the development of fluorescence based glucose sensors resulting from the advances in the design of new receptor systems for glucose recognition and the utilization of new fluorescence transduction schemes.

Biosensors and Bioelectronics

Vaccine, 2020

Performing a genome-wide association study (GWAS) might add to a better understanding of the deve... more Performing a genome-wide association study (GWAS) might add to a better understanding of the development of claw disorders and the need for trimming. Therefore, the aim of the current study was to perform a GWAS on claw disorders and trimming status and to validate the results for claw disorders based on an independent data set. Data consisted of 20,474 cows with phenotypes for claw disorders and 50,238 cows with phenotypes for trimming status. Recorded claw disorders used in the current study were double sole (DS), interdigital hyperplasia (IH), sole hemorrhage (SH), sole ulcer (SU), white line separation (WLS), a combination of infectious claw disorders consisting of (inter-) digital dermatitis and heel erosion, and a combination of laminitis-related claw disorders (DS, SH, SU, and WLS). Of the cows with phenotypes for claw disorders, 1,771 cows were genotyped and these cow data were used for the GWAS on claw disorders. A SNP was considered significant when the false discovery rate ≤ 0.05 and suggestive when the false discovery rate ≤ 0.20. An independent data set of 185 genotyped bulls having at least 5 daughters with phenotypes (6,824 daughters in total) for claw disorders was used to validate significant and suggestive SNP detected based on the cow data. To analyze the trait "trimming status" (i.e., the need for claw trimming), a data set with 327 genotyped bulls having at least 5 daughters with phenotypes (18,525 daughters in total) was used. Based on the cow data, in total 10 significant and 45 suggestive SNP were detected for claw disorders. The 10 significant SNP were associated with SU, and mainly located on BTA8. The suggestive SNP were associated with DS, IH, SU, and laminitis-related claw disorders. Three of the suggestive SNP were validated in the data set of 185 bulls, and were located on BTA13, BTA14, and BTA17. For infectious claw disorders, SH, and WLS, no significant or suggestive SNP associations were detected. For trimming status, 1 significant and 1 suggestive SNP were detected, both located close to each other on BTA15. Some significant and suggestive SNP were located close to SNP detected in studies on feet and leg conformation traits. Genes with major effects could not be detected and SNP associations were spread across the genome, indicating that many SNP, each explaining a small proportion of the genetic variance, influence claw disorders. Therefore, to reduce the incidence of claw disorders by breeding, genomic selection is a promising approach.

BioFactors, 2022

The CD36/FAT scavenger receptor/fatty acids transporter regulates cellular lipid accumulation imp... more The CD36/FAT scavenger receptor/fatty acids transporter regulates cellular lipid accumulation important for inflammation, atherosclerosis, lipotoxicity, and initiation of cellular senescence. Here we compared the regulatory effects of the vitamin E analogs alpha‐tocopherol (αT), alpha‐tocopheryl phosphate (αTP), and αTP/βCD (a nanocarrier complex between αTP and β‐cyclodextrin [βCD]) and investigated their regulatory effects on lipid accumulation, phagocytosis, and senescence in THP‐1 monocytes and macrophages. Both, αTP and αTP/βCD inhibited CD36 surface exposition stronger than αT leading to more pronounced CD36‐mediated events such as inhibition of DiI‐labeled oxLDL uptake, phagocytosis of fluorescent Staphylococcus aureus bioparticles, and cell proliferation. When compared to βCD, the complex of αTP/βCD extracted cholesterol from cellular membranes with higher efficiency and was associated with the delivery of αTP to the cells. Interestingly, both, αTP and more so αTP/βCD inhibi...

ACS Applied Bio Materials, 2020

Polymeric biomaterials have been used in a variety of applications, like cargo delivery and tissu... more Polymeric biomaterials have been used in a variety of applications, like cargo delivery and tissue scaffolding, because they are easily synthesized and can be adapted to many systems. However, there is still a need to further enhance and improve their functions to progress their use in the biomedical field. A promising solution is to modify the polymer surfaces with peptides that can increase biocompatibility, cellular interactions, and receptor targeting. In recent years, peptide modifications have been used to overcome many challenges to polymer biomaterial development. This review discusses recent progress in developing peptide-modified polymers for therapeutic applications including cell-specific targeting and tissue engineering. Furthermore, we will explore some of the most frequently studied base components of these biomaterials.

Ecotoxicology and Environmental Safety, 2021

Carcinogens are emitted in significant quantities at fire scenes and are a major contributor in t... more Carcinogens are emitted in significant quantities at fire scenes and are a major contributor in the increased cancer risk observed in firefighters when compared to the general population. A knowledge gap exists in the current understanding of the distribution of these toxic compounds within a localized fire incident response arena. Here, we employ stationary silicone-based passive samplers at controlled live fire trainings to evaluate the deposition behavior of polyaromatic hydrocarbons (PAHs) emitted by fires. Our findings indicate significantly greater total PAH exposure in fires fueled by biomass and wood compared to fires burning cleaner fuels, such as propane. A 22% increase in total PAH deposition and a 68% increase in high molecular weight PAH deposition was recorded for biomass fueled fires compared to propane fueled fires. Furthermore, we observe that heavier molecular weight PAHs exhibit a pronounced deposition front within a certain radius of the hot zone, whereas low molecular weight PAHs are more uniformly distributed throughout the area. These findings highlight that the warm zones and cold zones of fire situations yield elevated levels of carcinogen exposure to first responders within them. We anticipate that these findings will help inform decisions made by emergency personnel when evaluating risk for the hot zone, warm zone, and cold zone of urban fires helping ease the carcinogenic risk experienced.

Nanomedicine: Nanotechnology, Biology and Medicine, 2021

A mediator-free, non-enzymatic electrochemical biosensor was constructed by covalent immobilizati... more A mediator-free, non-enzymatic electrochemical biosensor was constructed by covalent immobilization of a genetically engineered periplasmic glutamate binding protein onto gold nanoparticle-modified, screen-printed carbon electrodes (GluBP/AuNP/SPCE) for the purpose of direct measurement of glutamate levels. Glutamate serves as the predominant excitatory neurotransmitter in the central nervous system. As high levels of glutamate are an indicator of many neurologic disorders, there is a need for advancements in glutamate detection technologies. The biosensor was evaluated for glutamate detection by cyclic voltammetry. Binding of glutamate to the immobilized glutamate binding protein results in a conformational change of the latter that alters the microenvironment on the surface of the sensor, which is manifested as a change in signal. Dose-response plots correlating the electrochemical signal to glutamate concentration revealed a detection limit of 0.15 μM with a linear range of 0.1-0.8 μM. Selectivity studies confirmed a strong preferential response of the biosensor for glutamate against common interfering compounds.

Ecotoxicology and Environmental Safety, 2020

Compared to the general population, firefighters are known to sustain greater levels of exposure ... more Compared to the general population, firefighters are known to sustain greater levels of exposure to hazardous compounds, despite their personal protective equipment, also known as turnout gear. Among the most significant toxins that firefighters are chronically exposed to are polycyclic aromatic hydrocarbons (PAHs). Additionally, firefighters have also been noted to exhibit an increased incidence of certain types of cancer. Considering a probable link between exposure to PAHs and increased rates of cancer in the fire service, we aim to document ambient chemical concentrations in the firefighter work environment. Our strategy involves the use of siliconebased wristbands that have the capacity to passively sorb PAHs. To determine if wristbands can serve as an effective chemical monitoring device for the fire service, silicone wristbands were pilot-tested as personal sampling devices for work environment risk monitoring in active-duty firefighters. Recovered wristbands underwent multiple extraction steps, followed by GC-MS analysis to demonstrate their efficacy in monitoring PAHs in the firefighter environment. Initial findings from all wristband samples taken from firefighters showed multiple exposures to various PAHs of concern for the health of the firefighters when in a fire environment. In addition to PAH monitoring, we examined known and potential sources of PAH contamination in their work environment. To that end, profiles of elevated PAH concentrations were documented at various fire stations throughout South Florida, for individual firefighters both during station duties and active fire response.

Obesity Surgery, 2020

Purpose A subpopulation of weight loss surgery (WLS) patients endorse cannabis and/or opioid use;... more Purpose A subpopulation of weight loss surgery (WLS) patients endorse cannabis and/or opioid use; however, impact on post-WLS anxiety and depression is unclear. This study examined the influence of the independent and combined use of cannabis and opioids on (1) depression and anxiety, (2) duodenum serotonin and cortisol, and (3) total percent weight loss. Materials and Methods A cross-sectional analysis was conducted among patients (N = 18) who had biomarkers of serotonin and cortisol collected from the duodenum during WLS. Cannabis and opioid use was determined by self-reported lifetime, past-year, and past 30-day use. The Beck Anxiety Inventory and Depression Inventory-II assessed depression and anxiety symptoms. Total percent weight loss was calculated from pre-WLS and post-WLS weight (kg). Chi-squared analyses and t tests were conducted. Results Over a quarter (27.8%) were cannabis-only users and 16.7% used a combination of cannabis and opioids. None reported using only opioids in this sample. Combination users presented with greater depressive symptoms (22.7%, p = 0.01) and greater total percent weight loss (34.1%, p = 0.04) than cannabis users (7.8, 23.2%, respectively). Cannabis users had greater serotonin (p = 0.02) and cortisol (p = 0.01) levels than combination users and never users. Conclusions Cannabis users had greater cortisol levels than never users and combination users. Combination users had greater weight loss and depression symptoms than cannabis users. Future studies should consider a larger sample size, utilization of a cohort design to address causality, and examination of the type, dose, and route of cannabis and opioid administration to further understand the impact of the combined use of cannabis and opioids post-WLS.

American Journal of Psychiatry, 2020

Microbiota dysbiosis has been linked to major depressive disorder, but the mechanisms whereby the... more Microbiota dysbiosis has been linked to major depressive disorder, but the mechanisms whereby the microbiota modulates mood remain poorly understood. We show that Segmented filamentous bacteria (SFB)-deficient mice are resilient to the induction of depressive-like behavior, and are resensitized when SFB is reintroduced in the gut. SFB produces the quorum sensing molecule autoinducer-2 (AI-2) and promotes the production of serum amyloid protein-1 (SAA1) and SAA2 by the host, which increased Th17 cell production. Th17 cells were required to promote depressive-like behaviors by AI-2, as AI-2 administration did not promote susceptibility to depressive-like behaviors or SAA1 and SAA2 production in Th17-deficient mice after stress. Oleic acid, an AI-2 inhibitor, exhibited antidepressant properties, reducing depressive-like behavior, intestinal SAA1 and SAA2 production, and hippocampal Th17 cell accumulation. Patients with current major depressive disorder exhibited increased fecal IL-17A, SAA and SFB levels. These results reveal a novel mechanism by which bacteria alter mood. Medina-Rodriguez et al.

JCO Global Oncology, 2020

PURPOSE Firefighters around the world are exposed to physical hazards and toxic chemical agents d... more PURPOSE Firefighters around the world are exposed to physical hazards and toxic chemical agents during fire incident response. Occupational epidemiologic studies of the firefighter workforce have documented an excess cancer risk for brain, digestive, genitourinary, and lymphohematopoietic organs compared with the general population. Despite the elevated cancer risk, little is known about what specific types of carcinogenic chemicals first responders encounter during a typical work shift, particularly in low-resources settings, like the Dominican Republic. This pilot study characterizes objective measurements of carcinogenic exposure using passive sampling silicone-based wristbands among Dominican firefighters. METHODS Firefighters from a metropolitan fire service in the Dominican Republic were asked to wear a silicone-based wristband during one typical 24-hour shift. A pre- and postshift survey was administered to the firefighter to assess their self-reported sociodemographic, emplo...

Microchimica Acta, 2020

The development of a bioluminescent immunosensor is reported for the determination of zearalenone... more The development of a bioluminescent immunosensor is reported for the determination of zearalenone (ZEA) based on a peptide mimetic identified by phage display. The peptide mimetic GW, with a peptide sequence GWWGPYGEIELL, was used to create recombinant fusion proteins with the bioluminescent Gaussia luciferase (GLuc) that were directly used as tracers for toxin detection in a competitive immunoassay without the need for secondary antibodies or further labeling. The bioluminescent sensor, based on protein G-coupled magnetic beads for antibody immobilization, enabled determination of ZEA with a detection limit of 4.2 ng mL −1 (corresponding to 420 μg kg −1 in food samples) and an IC 50 value of 11.0 ng mL −1. The sensor performance was evaluated in spiked maize and wheat samples, with recoveries ranging from 87 to 106% (RSD < 20%, n = 3). Finally, the developed method was applied to the analysis of a naturally contaminated reference matrix material and good agreement with the reported concentrations was obtained.

Industrial Hygiene, 2018

watering of roadways during the mining operation. Employee education on health effects of dust ex... more watering of roadways during the mining operation. Employee education on health effects of dust exposure, work practices, maintenance of equipment and PPE, medical surveillance, chest X-rays and TB awareness and monitoring are essential in the elimination of silicosis.

Bariatric Surgical Practice and Patient Care, 2020

Background: Abnormal cortisol and serotonin concentrations are reported in obese, anxious, and/or... more Background: Abnormal cortisol and serotonin concentrations are reported in obese, anxious, and/or depressed individuals. We examined how duodenal levels of these hormones correlated with self-reported anxiety and depression and their individual and combined contribution to weight loss among young metabolic and bariatric surgery (MBS) patients. Methods: Patients £30 years of age who had scheduled MBS were recruited. Weight, depression, and anxiety were collected within 2 weeks before MBS, and weight was again collected 6-months post-MBS. Duodenum serotonin and cortisol tissue samples were collected during MBS. Results: The majority of the sample (N = 18, mean age 23.6 years, standard deviation: 4.8 years) was female (72.2%) and Hispanic (66.7%), and 33.3% were non-Hispanic black. Duodenum cortisol (pg/mL) was inversely correlated with the Beck Anxiety Inventory (r =-0.76, p = 0.04) and Beck Depression Inventory (BDI)-II (r =-0.83, p = 0.02). For every pg/mL increase in the amount of (tissue) cortisol plus BDI-II, the score showed a 0.029 pound increase post-MBS (p = 0.02). Conversely, after adjusting for age every unit increase in BDI-II score showed a 1.83 pound decrease post-MBS (p = 0.03). Conclusions: A combined effect of cortisol and depression had a significant effect on weight loss, while depression was independently associated with weight gain. Longitudinal biospecimen collection would add information to these complex relationships.

Skin Appendage Disorders, 2019