Disposable aptamer-sensor aided by magnetic nanoparticle enrichment for detection of salivary cortisol variations in obstructive sleep apnea patients.
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ABSTRACT:
SUBMITTER: Fernandez RE
PROVIDER: S-EPMC5740141 | biostudies-literature | 2017 Dec
REPOSITORIES: biostudies-literature
Publications
Disposable aptamer-sensor aided by magnetic nanoparticle enrichment for detection of salivary cortisol variations in obstructive sleep apnea patients.
Fernandez Renny Edwin RE Umasankar Yogeswaran Y Manickam Pandiaraj P Nickel Jeffrey C JC Iwasaki Laura R LR Kawamoto Burt K BK Todoki Kristen C KC Scott JoAnna M JM Bhansali Shekhar S
Scientific reports 20171221 1
We report a disposable point-of-care sensing platform specific to salivary cortisol detection. The sensor is inkjet printed on a paper substrate with a metalloporphyrin based macrocyclic catalyst ink that can electrochemically reduce cortisol, captured by aptamer functionalized magnetic nanoparticles. The sensor consists of a thin magnet disc, aligned at the back of the electrode, in order to populate the magnetic nanoparticle bound cortisol at the sensing electrode area. Proof of concept studie ...[more]
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Project description:BackgroundSelf-management of blood glucose (BG) is considered a norm for diabetes control. However, this invasive process is uncomfortable for patients, especially when intensive measurements with frequent finger pricks are required. Saliva, an alternative body fluid that is easily accessible and contains trace amount of glucose can be potentially used for the noninvasive monitoring of diabetes.MethodsAs a solution for real-time glucose measurements using saliva for diabetic care, we have developed an on-chip disposable glucose nano-biosensor through a layer-by-layer assembly process. In this work, a clinical study of 10 healthy subjects was conducted to determine the potential usefulness of salivary glucose (SG) sensors for glycemic control.ResultsFindings revealed (1) the individual BG/SG ratio at fasting was consistent over an entire year when there was no significant change of personal health; (2) the individual SG levels tracked closely with BG levels after meals; (3) a time difference of 15-30 minutes exists between peak levels of BG and SG; (4) 2 hours after a meal, the BG/SG ratio returned to a similar value at fasting.ConclusionsWe propose to measure fasting and pre- and 2-hour postprandial SG levels for self-management of glycemic levels. As a result, this article is not intended to replace the common BG tests. With preliminary results, we believe SG itself could be used as means for reliable diabetes monitoring and a potential fluid for prognosis of future disease.
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2012-09-01 | E-GEOD-38792 | biostudies-arrayexpress
Project description:Rationale: Obstructive sleep apnea (OSA) has been associated with metabolic dysregulation and systemic inflammation. This may be due to pathophysiologic effects of OSA on visceral adipose tissue. We sought to assess the transcriptional consequences of OSA on adipocytes by utilizing pathway-focused analyses. Methods: Patients scheduled to undergo ventral hernia repair surgery were recruited to wear a portable home sleep monitor for two nights prior to surgery. Visceral fat biopsies were obtained intra-operatively. RNA was extracted and whole-genome expression profiling was performed. Gene Set Enrichment Analysis (GSEA) was used to identify curated gene sets that were differentially enriched in OSA subjects. Network analysis was applied to a select set of highly enriched pathways. Results: 10 patients with OSA and 8 control subjects were recruited. There were no differences in age, gender, body mass index between the two groups, but the OSA subjects had a significantly higher respiratory disturbance index (19.2 vs. 0.6, P-value 0.05) and worse hypoxemia (minimum oxygen saturation 79.7% vs. 87.8%, P-value < 0.001). GSEA identified a number of gene sets up-regulated in adipose tissue of OSA patients including the pro-inflammatory NF-κB pathway and the proteolytic ubiquitin/proteasome module. A critical metabolic pathway, the peroxisome proliferator-activated receptor (PPAR), was down-regulated in subjects with OSA. Network analysis linked members of these modules together and identified regulatory hubs. Conclusions: OSA is associated with alterations in visceral fat gene expression. Pathway-based network analysis highlighted perturbations in several key pathways whose coordinated interactions may contribute to the metabolic dysregulation observed in this complex disorder.
2012-09-01 | GSE38792 | GEO
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Project description:PURPOSE:To analyse nocturnal intraocular pressure (IOP) fluctuations in patients with obstructive sleep apnea syndrome (OSAS) using a contact lens sensor (CLS) and to identify associations between the OSAS parameters determined by polysomnographic study (PSG) and IOP changes. METHOD:Prospective, observational study. Twenty participants suspected of having OSAS were recruited. During PSG study, IOP was monitored using a CLS placed in the eye of the patient. The patients were classified according to the apnea-hypopnea index (AHI) in two categories, severe (>30) or mild/moderate (<30) OSAS. We evaluated several parameters determined by the IOP curves, including nocturnal elevations (acrophase) and plateau times in acrophase (PTs) defined by mathematical and visual methods. RESULTS:The IOP curves exhibited a nocturnal acrophase followed by PTs of varying extents at which the IOP remained higher than daytime measurement with small variations. We found significant differences in the length of the PTs in patients with severe OSAS compared to those with mild/moderate disease (P = 0.032/P = 0.028). We found a positive correlation between PTs and OSAS severity measured by the total number of apneic events (r = 0.681/0.751 P = 0.004/0.001) and AHI (r = 0.674/0.710, P = 0.004/0.002). Respiratory-related arousal and oxygen saturation also were associated significantly with the IOP PT length. CONCLUSIONS:Periods of nocturnal IOP elevation lasted longer in severe OSAS patients than those with mild/moderate OSAS and correlate with the severity of the disease. The length of the nocturnal PT is also associated to respiratory parameters altered in patients with OSAS.
| S-EPMC7053760 | biostudies-literature