Decentralized vitamin C & D dual biosensor chip: Toward personalized immune system support.

Combating the ongoing COVID-19 pandemic has put the spotlight on nutritional support of the immune system through consumption of vitamins C and D. Accordingly, there are urgent demands for an effective on-the-spot multi-vitamin self-testing platform that monitors the levels of these immune-supporting micronutrients for guiding precision nutrition recommendations. Herein, we present a compact bioelectronic dual sensor chip aimed at frequent on-the-spot simultaneous monitoring of the salivary vitamin C and D dynamics. The new bioelectronic chip combines a new electrocatalytic vitamin C amperometric assay along with competitive vitamin D immunoassay on neighboring electrodes, to perform selective and cross-talk free detection of both vitamins in a 10-µL saliva sample within 25 min. The distinct vitamin C or D temporal profiles obtained for different individuals after vitamin supplementation indicate the potential of the new bioelectronic chip strategy for enhancing personalized nutrition towards guiding dietary interventions to meet individual nutrition needs and promote immune system health.

Impact of Arachidonic and Docosahexaenoic Acid Supplementation on Neural and Immune Development in the Young Pig.

Background: Human milk contains both arachidonic acid (ARA) and docosahexaenoic acid (DHA). Supplementation of infant formula with ARA and DHA results in fatty acid (FA) profiles, neurodevelopmental outcomes, and immune responses in formula-fed infants that are more like those observed in breastfed infants. Consequently, ARA and DHA have been historically added together to infant formula. This study investigated the impact of ARA or DHA supplementation alone or in combination on tissue FA incorporation, immune responses, and neurodevelopment in the young pig. Methods: Male pigs (N = 48 total) received one of four dietary treatments from postnatal day (PND) 2-30. Treatments targeted the following ARA/DHA levels (% of total FA): CON (0.00/0.00), ARA (0.80/0.00), DHA (0.00/0.80), and ARA+DHA (0.80/0.80). Plasma, red blood cells (RBC), and prefrontal cortex (PFC) were collected for FA analysis. Blood was collected for T cell immunophenotyping and to quantify a panel of immune outcomes. Myelin thickness in the corpus callosum was measured by transmission electron microscopy and pig movement was measured by actigraphy. Results: There were no differences in formula intake or growth between dietary groups. DHA supplementation increased brain DHA, but decreased ARA, compared with all other groups. ARA supplementation increased brain ARA compared with all other groups but did not affect brain DHA. Combined supplementation increased brain DHA levels but did not affect brain ARA levels compared with the control. Pigs fed ARA or ARA+DHA exhibited more activity than those fed CON or DHA. Diet-dependent differences in activity suggested pigs fed ARA had the lowest percent time asleep, while those fed DHA had the highest. No differences were observed for immune or myelination outcomes. Conclusion: Supplementation with ARA and DHA did not differentially affect immune responses, but ARA levels in RBC and PFC were reduced when DHA was provided without ARA. Supplementation of either ARA or DHA alone induced differences in time spent asleep, and ARA inclusion increased general activity. Therefore, the current data support the combined supplementation with both ARA and DHA in infant formula and raise questions regarding the safety and nutritional suitability of ARA or DHA supplementation individually.

Epidermal Enzymatic Biosensors for Sweat Vitamin C: Toward Personalized Nutrition.

Recent advances in wearable sensor technologies offer new opportunities for improving dietary adherence. However, despite their tremendous promise, the potential of wearable chemical sensors for guiding personalized nutrition solutions has not been reported. Herein, we present an epidermal biosensor aimed at following the dynamics of sweat vitamin C after the intake of vitamin C pills and fruit juices. Such skin-worn noninvasive electrochemical detection of sweat vitamin C has been realized by immobilizing the enzyme ascorbate oxidase (AAOx) on flexible printable tattoo electrodes and monitoring changes in the vitamin C level through changes in the reduction current of the oxygen cosubstrate. The flexible vitamin C tattoo patch was fabricated on a polyurethane substrate and combined with a localized iontophoretic sweat stimulation system along with amperometric cathodic detection of the oxygen depletion during the enzymatic reaction. The enzyme biosensor offers a highly selective response compared to the common direct (nonenzymatic) voltammetric measurements, with no effect on electroactive interfering species such as uric acid or acetaminophen. Temporal vitamin C profiles in sweat are demonstrated using different subjects taking varying amounts of commercial vitamin C pills or vitamin C-rich beverages. The dynamic rise and fall of such vitamin C sweat levels is thus demonstrated with no interference from other sweat constituents. Differences in such dynamics among the individual subjects indicate the potential of the epidermal biosensor for personalized nutrition solutions. The flexible tattoo patch displayed mechanical resiliency to multiple stretching and bending deformations. In addition, the AAOx biosensor is shown to be useful as a disposable strip for the rapid in vitro detection of vitamin C in untreated raw saliva and tears following pill or juice intake. These results demonstrate the potential of wearable chemical sensors for noninvasive nutrition status assessments and tracking of nutrient uptake toward detecting and correcting nutritional deficiencies, assessing adherence to vitamin intake, and supporting dietary behavior change.

Erythrocyte fatty acid status in a convenience sample of residents of the Guatemalan Pacific coastal plain.

We report the fatty acid composition, and in particular, the n-3 and n-6 long-chain polyunsaturated fatty acids (LCPUFA), in erythrocytes from a convenience sample of 158 women and 135 schoolchildren residing in the southern Pacific Coast of Guatemala. Erythrocyte fatty acids were analyzed by gas-liquid chromatography with flame ionization detection and the profiles were expressed as a weight percent; the Omega-3 Index values were also determined. Schoolchildren had significantly higher mean ARA and total n-6 fatty acid levels than the women. Women had significantly higher EPA fatty acid levels than schoolchildren, but the reverse was true for DHA. For mean total n-3 fatty acid concentration, women and schoolchildren had similar values. The red cell weight percentages of selected fatty acids were also similar in women and schoolchildren. As compared with erythrocyte fatty acid data from developed countries, Guatemalan women and schoolchildren had consistently lower LCPUFA values. The traditional diet of Guatemalans living in the Pacific coastal region provided a worse erythrocyte fatty acid profile than that typically obtained from a Western diet. Additional fatty acid composition studies with associated dietary intake data in other inland locations may be useful for the interpretation of the nutritional status of Guatemalan children and adults.

A 3-week dietary bioequivalence study in preweaning farm piglets of two sources of docosahexaenoic acid produced from two different organisms.

Docosahexaenoic acid (DHA) and arachidonic acid (ARA) are components of human breast milk and commonly added to infant formula. The first DHA-containing algal oil for infant formulas was DHASCO® produced from the microalgae Crypthecodinium cohnii. Recently, new DHA-rich oil was obtained from the microalgae Schizochytrium sp., herein named DHASCO-B. The objectives of this study were to evaluate the bioequivalence of DHASCO-B to DHASCO when administered in a blend with ARA oil and the potential effects after 3weeks' administration in milk replacer formula to preweaning farm piglets. DHASCO-B and DHASCO were added to formula at concentrations 0.32% and 0.96% DHA (% of total fatty acids). There were no test article-related effects of any diet on piglet growth and development (clinical observations, body weight, food consumption), or clinical pathology parameters (hematology, clinical chemistry, coagulation and urinalysis). In addition, there were no adverse effects at terminal necropsy (macro- and microscopic pathology evaluations). DHA content in plasma, RBC, heart, liver and brain showed dose-related accumulation and confirmed no differences between corresponding DHASCO-B and DHASCO groups. Therefore, dietary exposure to DHASCO-B and DHASCO was well tolerated by the preweaning piglets during the 3-week dosing period right after birth and DHASCO-B and DHASCO were bioequivalent.

Evaluation of a safety resheathable winged steel needle for prevention of percutaneous injuries associated with intravascular-access procedures among healthcare workers.

OBJECTIVE: To compare the percutaneous injury rate associated with a standard versus a safety resheathable winged steel (butterfly) needle. DESIGN: Before-after trial of winged steel needle injuries during a 33-month period (19-month baseline, 3-month training, and 11-month study intervention), followed by a 31-month poststudy period. SETTING: A 1,190-bed acute care referral hospital with inpatient and outpatient services in New York City. PARTICIPANTS: All healthcare workers performing intravascular-access procedures with winged steel needles. INTERVENTION: Safety resheathable winged steel needle. RESULTS: The injury rate associated with winged steel needles declined from 13.41 to 6.41 per 100,000 (relative risk [RR], 0.48; 95% confidence interval [CI95], 0.31 to 0.73) following implementation of the safety device. Injuries occurring during or after disposal were reduced most substantially (RR, 0.15; CI95, 0.06 to 0.43). Safety winged steel needle injuries occurred most often before activation of the safety mechanism was appropriate (39%); 32% were due to the user choosing not to activate the device, 21% occurred during activation, and 4% were due to improper activation. Preference for the safety winged steel needle over the standard device was 63%. The safety feature was activated in 83% of the samples examined during audits of disposal containers. Following completion of the study, the safety winged steel needle injury rate (7.29 per 100,000) did not differ significantly from the winged steel needle injury rate during the study period. CONCLUSION: Implementation of a safety resheathable winged steel needle substantially reduced injuries among healthcare workers performing vascular-access procedures. The residual risk of injury associated with this device can be reduced further with increased compliance with proper activation procedures.