Optical Nanobiosensor Based on Surface-Enhanced Raman Spectroscopy and Catalytic Hairpin Assembly for Early-Stage Lung Cancer Detection via Blood Circular RNA

Lung cancer has become the leading cause of cancer-related deaths globally. However, early detection of lung cancer remains challenging, resulting in poor outcomes for the patients. Herein, we developed an optical biosensor integrating surface-enhanced Raman spectroscopy (SERS) with a catalyzed hairpin assembly (CHA) to detect circular RNA (circRNA) associated with tumor formation and progression (circSATB2). The signals of the Raman reporter were considerably enhanced by generating abundant SERS "hot spots" with a core-shell nanoprobe and 2D SERS substrate with calibration capabilities. This approach enabled the sensitive (limit of detection: 0.766 fM) and reliable quantitative detection of the target circRNA. Further, we used the developed biosensor to detect the circRNA in human serum samples, revealing that patients with lung cancer had higher circRNA concentrations than healthy subjects. Moreover, we characterized the unique circRNA concentration profiles of the early stages (IA and IB) and subtypes (IA1, IA2, and IA3) of lung cancer. These results demonstrate the potential of the proposed optical sensing nanoplatform as a liquid biopsy and prognostic tool for the early screening of lung cancer.

Reduce, Replace, Refine: Determining A Posteriori Reference Intervals for Biochemistry in Hermann's Tortoise (Testudo hermanni)

Biochemical and hematological analyses are important for the assessment of animal health. However, for most wild species their use is hindered by the scarcity of reliable reference intervals. Indeed, collecting body fluids (e.g., blood, urine) in free-ranging animals is often technically challenging. Further, sampling many individuals would be essential to consider major sources of variations, such as species, populations, sex, age, and seasons. One alternative, according to the reduction, refinement, and replacement framework, is to establish reference intervals a posteriori using literature survey and unpublished data. We produced reference intervals for free-ranging Hermann's tortoises (Testudo hermanni), using analyses performed on blood samples collected in previous studies and conservation programs conducted in the field between 2010 and 2016 in southern France (n=195 individuals). Thirteen parameters were analyzed: packed-cell volume, blood concentrations of corticosterone, testosterone, glycemia, cholesterol, triglyceride, urea, uric acid, calcium, sodium, potassium, asparagine aminotransferase (AST), and alanine aminotransferases (ALT). Reference intervals for subgroups defined by sex and season were relevant for corticosterone, triglyceride, and calcium (sex) and cholesterol (season). Comparing our results with those obtained in captive individuals in Germany, except for urea and AST levels the intervals from both free-ranging versus captive tortoises were similar, suggesting that reference intervals established from captive individuals may be suitable for free-ranging populations in this species.

Analysis of blood composition by porcine breeding cycle

BACKGROUND

Pigs for biomedical research are administered commercial fluids made for human consumption when they receive intravenous (IV) fluid therapy. Although pigs and humans have slightly different bodily fluid compositions, the composition shift happens at the same rate as their rapid growth.

OBJECTIVE

The study aimed to analyse the composition of porcine blood according to breeding cycle using a portable blood analyser and provides data for developing customized IV fluids for pigs.

METHODS

Pigs were sorted 25, 50, 100 and 120 days after birth, and sows were classified into candidate, pregnant and farrowing groups. A blood sample was collected from the external jugular vein and analysed using the EPOC blood analysis system using haematological, biochemical and gas parameters.

RESULTS

There was no difference among pig groups by age, but hematocrit and haemoglobin amounts decreased in sows after farrowing, but their concentrations were higher as compared to pigs. Glucose gradually reduced as age increased in pigs and during pregnancy in sows.

CONCLUSION

This study provided a comprehensive analysis of porcine blood composition by breeding cycle and highlighted the importance of glucose supplementation for IV fluid therapy in pigs.

Retrospective study using biosensor data of a milking Holstein cow with jejunal haemorrhage syndrome

Jejunal haemorrhage syndrome (JHS) is a sporadic and fatal enterotoxaemic disease in dairy cows associated with acute development and poor prognosis despite treatment. A 5-year-old Holstein cow with no reported pregnancy, three calving numbers, and 303 days in milk presented with hypothermia, discomfort, and inappetence. Anaemia, dehydration, faeces with blood clots, and absence of rumen and bowel movements were observed. We identified the presence of neutrophilia, hyperglycaemia, hypoproteinaemia, azotaemia, hyperlactatemia, hypocalcaemia, hypermagnesemia, hypokalaemia, and hypochloraemia through blood analyses. Necropsy and histopathologic examination revealed a dilated bluish-purple jejunum, blood clots within the jejunum, neutrophil infiltration into the submucosa of the jejunum, and vascular necrosis. Retrospective examination revealed extraordinary patterns of rumination time, activity, rumen mobility, and rumen temperature using biosensors and decreased milk yield. The abnormalities in the affected cow were detected before recognition by farm workers. To the best of our knowledge, this is the first report to examine data from biosensors in a cow with JHS. Our findings suggest that using biometric data may help understand the development of JHS.

Blood Profiling of Athletes after COVID-19: Differences in Blood Profiles of Post-COVID-19 Athletes Compared to Uninfected Athletic Individuals-An Exploratory Analysis

Blood profiling data in athletic populations and their respective responses to SARS-CoV-2 infection are lacking. Thus, this exploratory pilot study aimed to analyze and compare clinical blood markers in previously infected trained athletes (ATH; 30 m/29 f) and a not previously infected healthy athletic control group (HC; 12 m/19 f). The ATH group undertook a sports medical examination which included extended blood analyses. Blood profiles with a total of 74 variables were assessed (blood counts, pro-/inflammatory and immunological markers, and micronutrients), and the ATH group was compared to the age-matched, vaccinated HC group with comparable athletic back grounds, though without previous SARS-CoV-2-infections. The ATH group showed lower IgG, Troponin-T levels, and they had a lower complement/acute-phase protein activation. Furthermore, Vitamin D levels were lower and electrolyte/micronutrient concentrations were higher in ATH. Soluble transferrin receptor as a marker of erythrocyte turnover was decreased whereas PTT as a coagulation marker was increased. Subgroup analyses according to sex revealed more differences between the women of the ATH and HC groups (for 25 different variables) than between the men (for 5 different variables), especially for immunological and metabolic variables. In particular, the immune system and electrolyte/micronutrient status should be observed frequently and sex-specifically in this athletic cohort.

Feeding behaviour, locomotion rhythms and blood biochemistry of the neotropical red-tail catfish (Phractocephalus hemioliopterus)

The study evaluated the feeding behaviour of Phractocephalus hemioliopterus through the animals' ability to adapt to the self-feeding system, their preferred feeding times and locomotor activity, as well as the blood biochemistry of juveniles fed in a light/dark cycle. The study was carried out through two experiments, the first of which contained two phases. In experiment 1 - phase I, 24 juveniles (35.28 ± 0.62 g) were distributed in eight 48 l tanks. The tanks were equipped with a self-feeding system and the experiment consisted of evaluating whether the animals were able to adapt to the self-feeding system, as well as evaluating the preferred feeding times and locomotor activity of these animals. A feeding challenge to the animals was introduced in phase II, based on the results of phase I. The results of the first phase evidenced a nocturnal feeding preference. Thus, the feeding challenge consisted of measuring whether the animal would feed during the day and how long it would take to adapt. When the animals consumed 100% of the amount of feed provided daily, phase II was ended. In experiment 2, 24 juveniles of P. hemioliopterus (182.00 ± 14.03 g) were distributed in eight 96 l tanks. This experiment consisted of two treatments with four repetitions, one with exclusive feeding during the middle of the light cycle and another with exclusive feeding in the middle of the dark cycle. At the end, blood samples were collected from the animals for blood biochemistry evaluations. In experiment 1 - phase I, the results showed that the fish adapted very well to the self-feeding system and had a strictly nocturnal feeding behaviour and locomotor rhythm. When they were submitted to the feeding challenge in phase II, the feed intake was stabilized from the 17th day onwards, proportionally to the nocturnal consumption observed in the first phase, thus demonstrating feeding plasticity. In experiment 2, the feeding times influenced the animals' biochemical parameters. Animals fed during the night had higher values of cholesterol and triglycerides than animals fed during the day. It is concluded that P. hemioliopterus has fast adaptability to a self-feeding system, with strictly nocturnal feeding and locomotor behaviours. However, it has feeding plasticity, adapting its behaviour according to food availability. Blood biochemical parameters are influenced by the light/dark feeding cycle.

Use of Nanoparticle Decorated Surface-Enhanced Raman Scattering Active Sol-Gel Substrates for SALDI-MS Analysis

Spectroscopy and mass spectrometry techniques are sometimes combined into the same analytical workflow to leverage each technique's analytical benefits. This combined workflow is especially useful in forensic and medical contexts where samples are often precious in nature. Here, we adopt metal nanoparticle (NP) doped sol-gel substrates, initially developed for surface-enhanced Raman scattering (SERS) analysis, as surface-assisted laser desorption/ionization-mass spectrometry (SALDI-MS) substrates. Using dried blood and sample protocols previously developed for SERS analysis, we observe heme-related spectral features on both silver and gold NP substrates by SALDI-MS, demonstrating dual functionality for these orthogonal techniques. Modifying the dried blood extraction procedures also allows for the observation of blood triacylglycerols by SALDI-MS. This is the first demonstration of a SERS/SALDI-MS substrate based on a sol-gel scaffold and the first demonstration of a gold NP sol-gel substrate for SALDI-MS which features lower substrate-related SALDI-MS background compared to the silver substrate.

Relationship between Blood Parameters and Outcome in Rescued Roe Deer

Veterinary facility admissions of wild animals are increasing alongside the interest in wildlife diseases. To improve animal welfare, it is therefore important to increase veterinarians’ knowledge of wild animal medicine and to improve the clinical and diagnostic procedures, especially in the case of patients affected by trauma or multiple traumas. Blood analysis can be a quick and minimally invasive way of gathering useful clinical information for adequate treatment and management, and, together with a good clinical examination, to help predict hospitalisation outcomes. Few papers have reported reference ranges for the haematological and biochemical parameters of roe deer. This study evaluates the haematological and biochemical parameters in traumatised roe deer in relation to animal hospitalisation outcomes. The study was carried out on a cohort of 98 roe deer divided into groups according to their age and hospitalisation outcome. For each animal, a panel of haematological and biochemical parameters was performed. Significant differences were found between unweaned (<4 months old) groups in terms of MCV, MCH, CK, creatinine, total bilirubin, direct bilirubin, and indirect bilirubin, and between weaned (>4 months old) groups for total bilirubin. Creatine kinase, creatinine, and bilirubin may be useful indicators to correlate with the severity of trauma and help predict prognosis.

Hematology and biochemistry reference intervals for American crocodiles (Crocodylus acutus) in South Florida

The American crocodile (Crocodylus acutus) is considered a vulnerable species by the International Union for Conservation of Nature (IUCN) Red List across its range and classified as locally threatened in several countries. There is a lack of knowledge involving hematological and physiological parameters in American crocodile populations, limiting our understanding of what are considered "normal" blood analyte results for the species and how to link them with health assessments. In this study, we analyzed 40 hematological and biochemical parameters and estimated reference intervals (RIs) for 35 of them based on 436 clinically healthy wild American crocodiles caught in South Florida between 2015 and 2021. Crocodiles were captured across three areas with different levels of human influence [low = Everglades National Park (ENP), medium = Biscayne Bay Estuary (BBE), and high = Turkey Point Nuclear Power Plant (TP)]. There was very strong-to-strong evidence for an effect of where animals were caught on five analytes: basophils %, phosphorus, proportion of (pr) alpha-2 globulins, absolute count (abs) of gamma globulins, and corticosterone, so no reference values were estimated but general statistics are presented and discussed. From the remaining analytes, we found no evidence that sex or size class had an effect on red blood cell (RBC), azurophils and monocytes abs, triglycerides, and albumin abs. However, we did find moderate-to-strong evidence that sex influenced azurophils % and size class influenced white blood cell (WBC), heterophils %, monocytes %, basophils abs, creatine phosphokinase (CPK), potassium, glucose, bile acids, alpha-1 globulin abs, and alpha-2 globulin pr and abs. Finally, there was strong evidence that both sex and size class influenced PCV, lymphocytes % and abs, eosinophils % and abs, aspartate aminotransferase (AST), calcium, sodium, chloride, total protein, albumin/globulin (A/G) ratio, albumin pr, alpha-1 globulin, and beta globulin abs. Intraspecific analysis showed that size is the variable that most influenced analytes explaining up to 29% of the variation, which relates to our findings based on intraindividual analysis. We compared our results with blood parameters reported for conspecifics as well as closely related species and discussed implication of those results for clinical diagnosis and American crocodile conservation.

Testing the link between isoaspartate and Alzheimer's disease etiology

Isoaspartate (isoAsp) is a damaging amino acid residue formed in proteins as a result of spontaneous deamidation. IsoAsp disrupts protein structures, making them prone to aggregation. Here we strengthened the link between isoAsp and Alzheimer's disease (AD) by novel approaches to isoAsp analysis in human serum albumin (HSA), the most abundant blood protein and a major carrier of amyloid beta (Aβ) and phosphorylated tau (p-tau) in blood. We discovered a reduced amount of anti-isoAsp antibodies (P < 0.0001), an elevated isoAsp level in HSA (P < 0.001), more HSA aggregates (P < 0.0001), and increased levels of free Aβ (P < 0.01) in AD blood compared to controls. We also found that deamidation significantly reduces HSA capacity to bind with Aβ and p-tau (P < 0.05). These suggest the presence in AD of a bottleneck in clearance of Aβ and p-tau, leading to their increased concentrations in the brain and facilitating their aggregations there.

Haematological and biochemical reference intervals for wild green turtles (Chelonia mydas): a Bayesian approach for small sample sizes

Animal health is directly linked to population viability, which may be impacted by anthropogenic disturbances and diseases. Reference intervals (RIs) for haematology and blood biochemistry are essential tools for the assessment of animal health. However, establishing and interpreting robust RIs for threatened species is often challenged by small sample sizes. Bayesian predictive modelling is well suited to sample size limitations, accounting for individual variation and interactions between influencing variables. We aimed to derive baseline RIs for green turtles (Chelonia mydas) across two foraging aggregations in North Queensland, Australia, using Bayesian generalized linear mixed-effects models (n = 97). The predicted RIs were contained within previously published values and had narrower credible intervals. Most analytes did not vary significantly with foraging ground (76%, 22/29), body mass (86%, 25/29) or curved carapace length (83%, 24/29). Length and body mass effects were found for eosinophils, heterophil:lymphocyte ratio, alkaline phosphatase, aspartate transaminase and urea. Significant differences between foraging grounds were found for albumin, cholesterol, potassium, total protein, triglycerides, uric acid and calcium:phosphorus ratio. We provide derived RIs for foraging green turtles, which will be helpful in future population health assessments and conservation efforts. Future RI studies on threatened species would benefit from adapting established veterinary and biomedical standards.

How Nordic Countries Enforce Impaired Driving Legislation

This article reviews how the Nordic countries of Denmark, Finland, Norway, and Sweden enforce their legislation pertaining to driving under the influence of alcohol and/or other impairing drugs. The evidence necessary for a successful prosecution of traffic offenders has undergone radical changes over the past 50 years. The once widely used clinical tests of impairment are no longer a major element of the prosecution case and a physician is more seldom required to examine apprehended drivers and document any clinical signs and symptoms of alcohol and/or drug influence. These clinical tests have been superseded by results derived from a comprehensive toxicological analysis of psychoactive substances in samples of the driver's blood. The current statutory limits of blood-alcohol concentration (BAC) are among the lowest in the world: Norway and Sweden (0.20 g/kg) and Denmark and Finland (0.50 g/kg). Results from using evidential quality breath-alcohol instruments are accepted as evidence in drunk-driving cases and this has necessitated setting statutory breath-alcohol concentration (BrAC) limits. Laws dealing with driving under the influence of drugs (DUID) other than alcohol have also been updated and made more pragmatic for prosecution of traffic offenders. In Finland and Sweden zero-tolerance laws exist, making it illegal to drive with any quantifiable amount of a scheduled drug in the driver's blood. Prescription drugs are exempt from this zero-tolerance mandate provided the medication was used in accordance with a physician's ordination. Lacking a valid prescription or if there is a supratherapeutic concentration of the drug in blood, this will lead to a prosecution for DUID. In Denmark and Norway threshold concentration limits have been established for many psychoactive drugs, both licit and illicit. After these stricter laws for DUID were introduced, the number of suspects apprehended by the police per year increased by as much as tenfold in some Nordic countries. There is increasing evidence that many traffic delinquents in the Nordic countries suffer from a substance-use disorder, because repeat-offending is a common occurrence. This suggests that some type of treatment and rehabilitation program might be more beneficial compared with conventional penalties for people arrested for DUI and/or DUID.

Association among Helicobacter pylori Infection, Tooth Loss, and Heavy Medal Exposure in a Chinese Rural Population

Previous research suggests that heavy metals may be associated with increased susceptibility to Helicobacter pylori infection. This study investigated the effect of heavy metal exposure (Pb and Cd) on tooth loss and H. pylori infection in a Chinese rural population, who live near a mining and smelting area. Blood samples were collected from the study participants to estimate the lead (Pb) and cadmium (Cd) exposure levels. H. pylori infection was analyzed using the 14C-urea breath test, and the number of missing teeth (MT), filled teeth (FT), and missing or filled teeth (MFT) were counted by conducting a physical examination. Regression analysis was used to assess the difference between H. pylori-positive and -negative individuals in the MT, FT, and MFT groups, adjusting for confounders. The H. pylori infection prevalence was higher in individuals in the high Cd or high Pb groups than that in the low Cd or low Pb groups (p < 0.05). In addition, greater numbers of FT and MFT were observed in individuals in the high Pb group than those in the low Pb group (p < 0.05). We further found 8.7% (95% CI, 2.8−23.8%, p = 0.017) of the effect of the high BPb level on H. pylori infection risk could be statistically explained by FT using amediation analyses in adjusted models, and 6.8% (95% CI, 1.6−24.8%, p = 0.066) by MFT. Furthermore, FT and MFT were significantly associated with increased risk for H. pylori infection (odds ratio (OR) = 4.938, 95% confidence interval (CI): 1.125−21.671; OR = 3.602, 95% CI: 1.218−10.648, respectively). Pb and Cd exposure may be associated with tooth loss and increased susceptibility to H. pylori infection, and tooth loss may be an independent risk factor for H. pylori infection.

Biocompatibility and Degradation Behavior of Molybdenum in an In Vivo Rat Model

The biocompatibility and degradation behavior of pure molybdenum (Mo) as a bioresorbable metallic material (BMM) for implant applications were investigated. In vitro degradation of a commercially available Mo wire (ø250 µm) was examined after immersion in modified Kokubo's SBF for 28 days at 37 °C and pH 7.4. For assessment of in vivo degradation, the Mo wire was implanted into the abdominal aorta of female Wistar rats for 3, 6 and 12 months. Microstructure and corrosion behavior were analyzed by means of SEM/EDX analysis. After explantation, Mo levels in serum, urine, aortic vessel wall and organs were investigated via ICP-OES analysis. Furthermore, histological analyses of the liver, kidneys, spleen, brain and lungs were performed, as well as blood count and differentiation by FACS analysis. Levels of the C-reactive protein were measured in blood plasma of all the animals. In vitro and in vivo degradation behavior was very similar, with formation of uniform, non-passivating and dissolving product layers without occurrence of a localized corrosion attack. The in vitro degradation rate was 101.6 µg/(cm2·d) which corresponds to 33.6 µm/y after 28 days. The in vivo degradation rates of 12, 33 and 36 µg/(cm2·d) were observed after 3, 6 and 12 months for the samples properly implanted in the aortic vessel wall. This corresponds with a degradation rate of 13.5 µm/y for the 12-month cohort. However, the magnitude of degradation strongly depended on the implant site, with the wires incorporated into the vessel wall showing the most severe degradation. Degradation of the implanted Mo wire neither induced an increase in serum or urine Mo levels nor were elevated Mo levels found in the liver and kidneys compared with the respective controls. Only in the direct vicinity of the implant in the aortic vessel wall, a significant amount of Mo was found, which, however, was far below the amounts to be expected from degrading wires. No abnormalities were detected for all timepoints in histological and blood analyses compared to the control group. The C-reactive protein levels were similar between all the groups, indicating no inflammation processes. These findings suggest that dissolved Mo from a degrading implant is physiologically transported and excreted. Furthermore, radiographic and µCT analyses revealed excellent radiopacity of Mo in tissues. These findings and the unique combination with its extraordinary mechanical properties make Mo an interesting alternative for established BMMs.

First Immunoassay for Measuring Isoaspartate in Human Serum Albumin

Isoaspartate (isoAsp) is a damaging amino acid residue formed in proteins mostly as a result of spontaneous deamidation of asparaginyl residues. An association has been found between isoAsp in human serum albumin (HSA) and Alzheimer’s disease (AD). Here we report on a novel monoclonal antibody (mAb) 1A3 with excellent specificity to isoAsp in the functionally important domain of HSA. Based on 1A3 mAb, an indirect enzyme-linked immunosorbent assay (ELISA) was developed, and the isoAsp occupancy in 100 healthy plasma samples was quantified for the first time, providing the average value of (0.74 ± 0.13)%. These results suggest potential of isoAsp measurements for supplementary AD diagnostics as well as for assessing the freshness of stored donor blood and its suitability for transfusion.

Effects of Transportation Stress on Complete Blood Count, Blood Chemistry, and Cytokine Gene Expression in Heifers

Blood samples were obtained from 16 high-risk heifers; eight were newly arrived from a 40 h road trip (0 days post-arrival (DPA)), whereas the other eight heifers had been in the feedlot at 25 DPA. Both groups were transported from the southeast tropical region of Mexico to a feedlot in the northeast and were sampled on the same day. The complete blood count, blood chemistry, and cytokine gene expression were analyzed. Gene expression was analyzed using specific primers to amplify and quantify the cDNA reverse transcribed from the mRNA transcripts for tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and interleukin (IL)-2. Higher values for hematocrit (p = 0.029), hemoglobin (p = 0.002), eosinophils (0.029), albumin (p = 0.014), alanine aminotransferase (p = 0.004), bilirubin (p = 0.003), cholesterol (p = 0.014), and cortisol (p = 0.051) were observed in the 0 DPA group than the 25 DPA group. In the electrophoresis of TNF-α amplification products, two non-specific bands were observed in the 0 DPA group. These bands were sequenced, and BLAST analysis suggested that they corresponded to bovine lymphotoxin and have not been reported previously related to stress. The TNF-α expression level was higher (p = 0.001) in the 25 DPA group than the 0 DPA group according to the semi-quantitative expression analysis. This may indicate a persistent inflammatory process that could be related to trauma and disease, which can negatively impact their subsequent health and growth performance. In conclusion, homeostatic disruption was apparent in the 0 DPA heifers, which showed higher cortisol and reductions in TNF-α levels and stress-induced bovine lymphotoxin (SIBL) co-expression.

Smartphone-Based Chemiluminescent Origami µPAD for the Rapid Assessment of Glucose Blood Levels

Microfluidic paper analytical devices (µPADs) represent one of the most appealing trends in the development of simple and inexpensive analytical systems for diagnostic applications at the point of care (POC). Herein, we describe a smartphone-based origami µPAD for the quantitative determination of glucose in blood samples based on the glucose oxidase-catalyzed oxidation of glucose leading to hydrogen peroxide, which is then detected by means of the luminol/hexacyanoferrate(III) chemiluminescent (CL) system. By exploiting the foldable µPAD format, a two-step analytical procedure has been implemented. First, the diluted blood sample was added, and hydrogen peroxide was accumulated, then the biosensor was folded, and a transport buffer was added to bring hydrogen peroxide in contact with CL reagents, thus promoting the CL reaction. To enable POC applicability, the reagents required for the assay were preloaded in the µPAD so that no chemicals handling was required, and a 3D-printed portable device was developed for measuring the CL emission using the smartphone’s CMOS camera. The µPAD was stable for 30-day storage at room temperature and the assay, displaying a limit of detection of 10 µmol L⁻¹, proved able to identify both hypoglycemic and hyperglycemic blood samples in less than 20 min.

ReCODE: A Personalized, Targeted, Multi-Factorial Therapeutic Program for Reversal of Cognitive Decline

Background: Alzheimer’s disease (AD) is the major cause of age-associated cognitive decline, and in the absence of effective therapeutics is progressive and ultimately fatal, creating a dire need for successful prevention and treatment strategies. We recently reported results of a successful proof-of-concept trial, using a personalized, precision medicine protocol, but whether such an approach is readily scalable is unknown. Objective: In the case of AD, there is not a single therapeutic that exerts anything beyond a marginal, unsustained, symptomatic effect. This suggests that the monotherapeutic approach of drug development for AD may not be an optimal one, at least when used alone. Using a novel, comprehensive, and personalized therapeutic system called ReCODE (reversal of cognitive decline), which proved successful in a small, proof-of-concept trial, we sought to determine whether the program could be scaled to improve cognitive and metabolic function in individuals diagnosed with subjective cognitive impairment, mild cognitive impairment, and early-stage AD. Methods: 255 individuals submitted blood samples, took the Montreal Cognitive Assessment (MoCA) test, and answered intake questions. Individuals who enrolled in the ReCODE program had consultations with clinical practitioners, and explanations of the program were provided. Participants had follow-up visits that included education regarding diet, lifestyle choices, medications, supplements, repeat blood sample analysis, and MoCA testing between 2 and 12 months after participating in the ReCODE program. Pre- and post-treatment measures were compared using the non-parametric Wilcoxon signed rank test. Results and Conclusions: By comparing baseline to follow-up testing, we observed that MoCA scores either significantly improved or stabilized in the entire participant pool—results that were not as successful as those in the proof-of-concept trial, but more successful than anti-amyloid therapies—and other risk factors including blood glucose, high-sensitivity C-reactive protein, HOMA-IR, and vitamin D significantly improved in the participant pool. Our findings provide evidence that a multi-factorial, comprehensive, and personalized therapeutic program designed to mitigate AD risk factors can improve risk factor scores and stabilize or reverse the decline in cognitive function. Since superior results were obtained in the proof-of-concept trial, which was conducted by a small group of highly trained and experienced physicians, it is possible that results from the use of this personalized approach would be enhanced by further training and experience of the practicing physicians. Nonetheless, the current results provide further support indicating the potential of such an approach for the prevention and reversal of cognitive decline.

Comparison of different spectral cameras for image-guided organ transplantation

SIGNIFICANCE

Hyperspectral and multispectral imaging (HMSI) in medical applications provides information about the physiology, morphology, and composition of tissues and organs. The use of these technologies enables the evaluation of biological objects and can potentially be applied as an objective assessment tool for medical professionals.

AIM

Our study investigates HMSI systems for their usability in medical applications.

APPROACH

Four HMSI systems (one hyperspectral pushbroom camera and three multispectral snapshot cameras) were examined and a spectrometer was used as a reference system, which was initially validated with a standardized color chart. The spectral accuracy of the cameras reproducing chemical properties of different biological objects (porcine blood, physiological porcine tissue, and pathological porcine tissue) was analyzed using the Pearson correlation coefficient.

RESULTS

All the HMSI cameras examined were able to provide the characteristic spectral properties of blood and tissues. A pushbroom camera and two snapshot systems achieve Pearson coefficients of at least 0.97 compared to the ground truth, indicating a very high positive correlation. Only one snapshot camera performs moderately to high positive correlation (0.59 to 0.85).

CONCLUSION

The knowledge of the suitability of HMSI cameras for accurate measurement of chemical properties of biological objects offers a good opportunity for the selection of the optimal imaging tool for specific medical applications, such as organ transplantation.

Deep UV Formation of Long-Term Stable Optical Bragg Gratings in Epoxy Waveguides and Their Biomedical Sensing Potentials

In this article, we summarize our investigations on optimized 248 nm deep ultraviolet (UV) fabrication of highly stable epoxy polymer Bragg grating sensors and their application for biomedical purposes. Employing m-line spectroscopy, deep UV photosensitivity of cross-linked EpoCore thin films in terms of responding refractive index change is determined to a maximum of Δn = + (1.8 ± 0.2) × 10⁻³. All-polymer waveguide Bragg gratings are fabricated by direct laser irradiation of lithographic EpoCore strip waveguides on compatible Topas 6017 substrates through standard +1/-1-order phase masks. According near-field simulations of realistic non-ideal phase masks provide insight into UV dose-dependent characteristics of the Bragg grating formation. By means of online monitoring, arising Bragg reflections during grating inscription via beforehand fiber-coupled waveguide samples, an optimum laser parameter set for well-detectable sensor reflection peaks in respect of peak strength, full width at half maximum and grating attenuation are derived. Promising blood analysis applications of optimized epoxy-based Bragg grating sensors are demonstrated in terms of bulk refractive index sensing of whole blood and selective surface refractive index sensing of human serum albumin.

Optical Investigation of Individual Red Blood Cells for Determining Cell Count and Cellular Hemoglobin Concentration in a Microfluidic Channel

We demonstrate a blood analysis routine by observing red blood cells through light and digital holographic microscopy in a microfluidic channel. With this setup a determination of red blood cell (RBC) concentration, the mean corpuscular volume (MCV), and corpuscular hemoglobin concentration mean (CHCM) is feasible. Cell count variations in between measurements differed by 2.47% with a deviation of −0.26×106 μL to the reference value obtained from the Siemens ADVIA 2120i. Measured MCV values varied by 2.25% and CHCM values by 3.78% compared to the reference ADVIA measurement. Our results suggest that the combination of optical analysis with microfluidics handling provides a promising new approach to red blood cell counts.

The effect of sample hemolysis on blood ethanol analysis using headspace gas chromatography

Hemolysis, a common occurrence in blood collected for chemical analysis, has been reported to affect analytical test results for some analytes depending upon the material tested and the analytical technique employed. The potential for hemolysis to impact blood ethanol determinations using headspace gas chromatography of samples diluted with an internal standard was investigated. A sample of non-hemolyzed blood and a matched sample of hemolyzed blood were both analyzed thirty times for ethanol concentration using headspace gas chromatography. The mean ethanol concentration measured for the non-hemolyzed samples was 0.0639 g/dl. The mean ethanol concentration measured for the hemolyzed samples was 0.0642 g/dl. The calculated t value, 1.897, was less than the critical t value, 2.002, at a 0.05 level of significance. There was no measured statistical difference detected between the mean blood ethanol concentration determined for a hemolyzed whole blood sample and a non-hemolyzed whole blood sample.

Kynurenic Acid Electrochemical Immunosensor: Blood-Based Diagnosis of Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder, characterized by a functional deterioration of the brain. Currently, there are selected biomarkers for its diagnosis in cerebrospinal fluid. However, its extraction has several disadvantages for the patient. Therefore, there is an urgent need for a detection method using sensitive and selective blood-based biomarkers. Kynurenic acid (KYNA) is a potential biomarker candidate for this purpose. The alteration of the KYNA levels in blood has been related with inflammatory processes in the brain, produced as a protective function when neurons are damaged. This paper describes a novel electrochemical immunosensor for KYNA detection, based on successive functionalization multi-electrode array. The resultant sensor was characterized by cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). The proposed biosensor detects KYNA within a linear calibration range from 10 pM to 100 nM using CA and EIS, obtaining a limit of detection (LOD) of 16.9 pM and 37.6 pM in buffer, respectively, being the lowest reported LOD for this biomarker. Moreover, to assess our device closer to the real application, the developed immunosensor was also tested under human serum matrix, obtaining an LOD of 391.71 pM for CA and 278.8 pM for EIS with diluted serum.

Interdigitated Sensor Optimization for Blood Sample Analysis

Interdigitated (ITD) sensors are specially adapted for the bioimpedance analysis (BIA) of low-volume (microliter scale) biological samples. Impedance spectroscopy is a fast method involving simple and easy biological sample preparation. The geometry of an ITD sensor makes it easier to deposit a sample at the microscopic scale of the electrodes. At this scale, the electrode size induces an increase in the double-layer effect, which may completely limit interesting bandwidths in the impedance measurements. This work focuses on ITD sensor frequency band optimization via an original study of the impact of the metalization ratio α. An electrical sensor model was studied to determine the best α ratio. A ratio of 0.6 was able to improve the low-frequency cutoff by a factor of up to 2.5. This theoretical approach was confirmed by measurements of blood samples with three sensors. The optimized sensor was able to extract the intrinsic electrical properties of blood in the frequency band of interest.

Changes in plasma pH and blood and urinary macromineral concentrations in experimentally induced hypocalcemic cows with Na2EDTA

This study was performed to confirm the alterations of blood and urine parameters in artificially induced hypocalcemic cows. For a 2 × 2 cross-over design, four non-pregnant, non-lactating Holstein Friesian cows (623 ± 63 kg) were utilized. Cows in the treatment and control group were infused with ethylenediaminetetraacetic acid (Na₂EDTA) solution and normal saline through an intravenous catheter for 3 hr, respectively. Laboratory analyses included complete blood cell count, plasma chemistry, blood gas analysis and urine chemistry. During the hypocalcemic period, abnormal signs were not observed clinically, hematologically nor biochemically either in groups. But, plasma calcium and magnesium concentrations continued to decrease throughout Na₂EDTA infusion, and significant group differences (P<0.05 or P<0.001) were detected until 5 hr after the initiation of infusion. Urinary excretions of these minerals were significantly reduced compared to the control group by 6 hr (Ca, P<0.05; Mg, P<0.001). Moreover, there is a significant group difference in the change in plasma pH at 1 hr after Na₂EDTA infusion (P<0.05) and maintained a decreased level until 6 hr. Consequently, the blood pH was diminished simultaneously with hypocalcemia and hypomagnesemia induction in cows infused with Na₂EDTA. This phenomenon may be one of the mechanisms to recover normocalcemia including maximizing the effect of parathyroid hormone, however, further studies are needed to elucidate the mechanism to alter the blood pH in hypocalcemia.

A Quantized CNN-Based Microfluidic Lensless-Sensing Mobile Blood-Acquisition and Analysis System

This paper proposes a microfluidic lensless-sensing mobile blood-acquisition and analysis system. For a better tradeoff between accuracy and hardware cost, an integer-only quantization algorithm is proposed. Compared with floating-point inference, the proposed quantization algorithm makes a tradeoff that enables miniaturization while maintaining high accuracy. The quantization algorithm allows the convolutional neural network (CNN) inference to be carried out using integer arithmetic and facilitates hardware implementation with area and power savings. A dual configuration register group structure is also proposed to reduce the interval idle time between every neural network layer in order to improve the CNN processing efficiency. We designed a CNN accelerator architecture for the integer-only quantization algorithm and the dual configuration register group and implemented them in field-programmable gate arrays (FPGA). A microfluidic chip and mobile lensless sensing cell image acquisition device were also developed, then combined with the CNN accelerator to build the mobile lensless microfluidic blood image-acquisition and analysis prototype system. We applied the cell segmentation and cell classification CNN in the system and the classification accuracy reached 98.44%. Compared with the floating-point method, the accuracy dropped by only 0.56%, but the area decreased by 45%. When the system is implemented with the maximum frequency of 100 MHz in the FPGA, a classification speed of 17.9 frames per second (fps) can be obtained. The results show that the quantized CNN microfluidic lensless-sensing blood-acquisition and analysis system fully meets the needs of current portable medical devices, and is conducive to promoting the transformation of artificial intelligence (AI)-based blood cell acquisition and analysis work from large servers to portable cell analysis devices, facilitating rapid early analysis of diseases.

Effect of different pre-analytical conditions on plasma lactate concentration

Introduction

Plasma lactate is a frequently used and important parameter for medical decision making. To setup a pre-analytical algorithm, we aimed to investigate the influence of different test tube additives, aliquoting, ice storage and haemolysis on plasma lactate concentrations for possible sparing critically ill (ICU) patients of additional blood drawing.

Materials and methods

In our study (N = 177), lactate concentration and haemolysis index (HI) were measured in aliquoted (AHP) and unaliquoted (HP) Li-heparin, NaF/K₃EDTA and NaF/KOX plasma, centrifuged within 15 minutes after venipuncture, on Cobas c501 analyzer. Differences were tested using the Wilcoxon’s test and Passing-Bablok regression. Clinical accuracy of results was assessed in 107 ICU patients based on reference interval and clinical decision limits.

Results

Lactate concentrations did not differ in NaF/K₃EDTA and NaF/KOX plasma (P = 0.855). No clinically significant difference of AHP compared to NaF/K₃EDTA lactate was found (y = 0.13 (0.08 to 0.19) + 1.02 (0.99 to 1.08) x) if samples were aliquoted within 30 minutes after venipuncture. On contrary, lactate concentrations in HP showed significant proportional difference (y = 0.07 (- 0.12 to 1.24) + 1.37 (1.22 to 1.56) x) and were clinically incorrect in 14% of patients. Transport in ice bath increases HI in NaF/K₃EDTA (P < 0.001), but without influencing lactate results compared to room temperature (y = 0.03 (- 0.06 to 1.00) + 1.05 (0.99 to 1.11) x).

Conclusions

Lactate determination in HP is unacceptable because of high proportional error and high risk of clinical inaccuracy compared to NaF/K₃EDTA. If pre-analytical conditions are met, AHP, NaF/K₃EDTA and NaF/KOX plasma can be used interchangeably. Aliquoted Li-heparin samples alow measurement of other biochemical tests from a single tube and can spare ICU patients from additional blood drawing. Storage in ice bath provides no additional stabilization in NaF/K₃EDTA tubes.

Prehospital Advanced Diagnostics and Treatment of Acute Stroke: Protocol for a Controlled Intervention Study

BACKGROUND

Acute ischemic stroke (AIS) is a medical emergency. The outcome is closely linked to the time elapsing from symptom onset to treatment, and seemingly small delays can mean the difference between full recovery and physical and cognitive dysfunction. Recanalization to allow blood to reenter the affected area is most efficient immediately after symptoms occur, and intravenous thrombolysis must be initiated no later than 4.5 hours after the symptom onset. A liable diagnosis is mandatory to administer the appropriate treatment. Prehospital diagnosis and, in cases where contraindications are ruled out, prehospital initiation of intravenous thrombolysis have been shown to significantly decrease the time from alarm to the treatment.

OBJECTIVE

The objective of this paper is to investigate the effectiveness of prehospital thrombolysis as measured by (1) time spent from symptom onset to treatment and (2) the number of patients treated within 4.5 hours. In addition, we want to conduct explorative studies. These will include (1) the use of biomarkers for diagnostic and prognostic use where we will collect blood samples from various time points, including the hyperacute phase and (2) the study of magnetic resonance imaging (MRI) images at day 1 to determine the infarct volume and if the time to thrombolysis has an influence on this.

METHODS

This is a prospective controlled intervention study. The intervention will involve a computed tomography (CT) and thrombolysis in a physician-manned ambulance called a mobile stroke unit (MSU). The control will be the conventional pathway where the patient is transported to the hospital for CT, and thrombolysis as per current procedure.

RESULTS

Patient inclusion has started and a total of 37 patients are enrolled (control and intervention combined). The estimated time to completed inclusion is 36 months, starting from May 2017. The results of this study will be analyzed and published at the end of the trial.

CONCLUSIONS

This trial aims to document the feasibility of saving time for all stroke patients by providing prehospital diagnostics and treatment, as well as transport to appropriate level of care, in a safe environment provided by anesthesiologists trained in prehospital critical care.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03158259; https://clinicaltrials.gov/show/NCT03158259 (Archived by WebCite at http://www.webcitation.org/6wxNEUMUD).

The local clinical validation of a new lithium heparin tube with a barrier: BD Vacutainer® Barricor LH Plasma tube

INTRODUCTION

Although serum-providing blood tubes with a barrier are still widely used due to their significant advantages, the use of blood tubes with a barrier to provide plasma is becoming widespread. We compared 22 analytes in a BD Vacutainer® Barricor LH Plasma tube for local clinical validation of this new lithium heparin tube with a barrier.

MATERIALS AND METHODS

Samples from 44 volunteers were collected in different tubes (Becton Dickinson and Company): Z tube without additive (reference), clot-activator tube with gel (SST), lithium heparin tube without gel (LiH), and lithium heparin tube with barrier (Barricor). Analyte concentrations in different tubes were compared with the reference tube. All tubes were also evaluated according to additional testing (different centrifugation durations, blood-sampling techniques and individual differences).

RESULTS

Aspartate aminotransferase (AST), glucose (Glc), potassium (K), lactate dehydrogenase (LD), sodium (Na), and total protein (TP) had a significant bias in Barricor (9.19%, - 3.24%, - 4.88%, 21.60%, - 0.40%, 5.03%, respectively) relative to the reference tube. There was no statistical difference between different centrifugation durations and individual differences for AST, K and LD in LiH and/or Barricor (P > 0.05). There was a significant bias for LD between LiH and Barricor in terms of blood-sampling techniques (21.2% and 12.4%, respectively).

CONCLUSIONS

Recently, the use of plasma has become prominent due to some of its advantages. In this study, plasma AST, K, LD, Glc and TP levels in Barricor were clinically different in comparison to serum. The results of additional tests showed that higher levels of LD in Barricor did not result from haemolysis, and they might be related to other factors including number of platelets, cellular fragility, or functional environment.

Analysis of gingival pocket microflora and biochemical blood parameters in dogs suffering from periodontal disease

BACKGROUND/AIM

Periodontal diseases in dogs are caused by bacteria colonising the oral cavity. The presence of plaque comprising accumulations of aerobic and anaerobic bacteria leads to the development of periodontitis. Due to the fact that in a large percentage of cases periodontal diseases remain undiagnosed, and consequently untreated, they tend to acquire a chronic character, lead to bacteraemia and negatively impact the health of internal organs. The aim of the present study was to perform a qualitative microbiological analysis of gingival pockets and determine the correlations between selected morphological and biochemical blood parameters and the extent periodontal diseases.

PATIENTS AND METHODS

Twenty-one dogs treated for periodontal diseases were qualified for the study and subsequently divided into two groups: with 3rd and 4th stage of periodontal disease. Swabs from the patients' gingival pockets were taken for bacteriological testing. Blood was tested for parameters including erythrocyte count, haemoglobin concentration, haematocrit values and leukocyte count. Blood serum was analyzed with respect to the concentrations of alanine transaminase (ALT), aspartate transaminase (AspAT/AST) and urea.

RESULTS

The microbiological analysis of gingival pockets indicated the presence of numerous pathogens with a growth tendency in bacterial cultures observed in dogs with advanced-stage periodontal disease. The concentration of biochemical blood markers was significantly higher in dogs with 4th stage of periodontal disease, to compared to the 3rd-stage group. Morphological parameters were not significantly different with the exception of haemoglobin concentration, which was lower in dogs with 4th stage disease. In both groups, elevated leukocyte counts were observed.

CONCLUSION

By conducting a detailed microbiological examination, it is possible to provide a better prognosis, plan adequate treatment and monitor dogs treated for peridontopathy.

MRI-diagnosed nonalcoholic fatty liver disease is correlated to insulin resistance in adolescents

RATIONALE AND OBJECTIVES

To evaluate the presence of nonalcoholic fatty liver disease (NAFLD) in eutrophic and obese adolescents with magnetic resonance imaging (MRI) and its relationship to insulin resistance and other potential biomarkers.

MATERIALS AND METHODS

A total of 50 adolescents (aged 11-17 years), including 24 obese and 26 eutrophic adolescents, were evaluated using MRI exams for NAFLD diagnosis. Blood analysis was performed to measure glucose, insulin, total cholesterol, high-density lipoprotein cholesterol, triglycerides, fibrinogen, aminotransferases, alkaline phosphatase, gamma-gt, and C-reactive protein. The Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) index was also calculated. Laboratory test results and anthropometric assessment were statistically analyzed to determine potential correlation with NAFLD prevalence.

RESULTS

The prevalence of NAFLD among the obese was significantly higher (83.3%; CI 95: 64.5-94.5%) than that of the eutrophic group (19.2%; CI 95: 7.4-37.6%). In multivariate analysis, only HOMA-IR was an independent risk factor for diagnosis NAFLD using MRI. Compared to eutrophic adolescents, the obese adolescents had significantly higher levels for all parameters measured except for total and high-density lipoprotein cholesterol, which were significantly lower.

CONCLUSION

The prevalence of NAFLD was 19.2% among eutrophic patients and 83.3% among obese patients. Only HOMA-IR was determined to be an independent risk factor for NAFLD.

Analysis of Biological Samples Using Paper Spray Mass Spectrometry: An Investigation of Impacts by the Substrates, Solvents and Elution Methods

Paper spray has been developed as a fast sampling ionization method for direct analysis of raw biological and chemical samples using mass spectrometry (MS). Quantitation of therapeutic drugs in blood samples at high accuracy has also been achieved using paper spray MS without traditional sample preparation or chromatographic separation. The paper spray ionization is a process integrated with a fast extraction of the analyte from the raw sample by a solvent, the transport of the extracted analytes on the paper, and a spray ionization at the tip of the paper substrate with a high voltage applied. In this study, the influence on the analytical performance by the solvent-substrate systems and the selection of the elution methods was investigated. The protein hemoglobin could be observed from fresh blood samples on silanized paper or from dried blood spots on silica-coated paper. The on-paper separation of the chemicals during the paper spray was characterized through the analysis of a mixture of the methyl violet 2B and methylene blue. The mode of applying the spray solvent was found to have a significant impact on the separation. The results in this study led to a better understanding of the analyte elution, on-paper separation, as well as the ionization processes of the paper spray. This study also help to establish a guideline for optimizing the analytical performance of paper spray for direct analysis of target analytes using mass spectrometry.

Variability in the blood/breath alcohol ratio and implications for evidentiary purposes

The breath analyzer is an indispensable tool for identifying alcohol levels among drivers. While numerous studies have shown high correlations between blood and breath alcohol concentrations, most are limited by the study design. This study seeks to assess this relationship by minimizing potential measurement bias, document time from alcohol consumption to testing, and adjusting for potential confounders. A blinded study was performed using conditions closely resembling those in the field. The Draeger 7110 MKIII IL breath analyzer was used to assess breath alcohol concentrations (BrAC). Participants were 61 healthy volunteers aged 21-37 years with body mass index ≤30 and no history of alcoholism. A total of 242 valid blood/breath tests were performed in four test sets. The study results showed a high correlation coefficient between BrAC and blood alcohol concentration (BAC) levels (r = 0.983) with high sensitivity (97%) and specificity (93%). This strong association between the breath analyzer and BAC persisted even after adjustment for various stages of alcohol absorption. These results illustrate the high diagnostic sensitivity of the breath analyzer in field-tested conditions.

Molecular analysis of blood with micro-/nanoscale field-effect-transistor biosensors

Rapid and accurate molecular blood analysis is essential for disease diagnosis and management. Field-effect transistor (FET) biosensors are a type of device that promise to advance blood point-of-care testing by offering desirable characteristics such as portability, high sensitivity, brief detection time, low manufacturing cost, multiplexing, and label-free detection. By controlling device parameters, desired FET biosensor performance is obtained. This review focuses on the effects of sensing environment, micro-/nanoscale device structure, operation mode, and surface functionalization on device performance and long-term stability.

Requirements and assessment of laboratory tests: Part 5 of a series on evaluation of scientific publications

BACKGROUND

Current laboratory tests exhibit high sensitivity and specificity combined with comparatively low costs thus favoring broad and uncritical ordering habits.

METHODS

Introduction of Bayes' theorem and discussion of its implications for laboratory test results in a mostly non-technical form, accompanied by a selective literature review.

RESULTS AND CONCLUSIONS

According to Bayes' theorem the positive predictive value of laboratory test results is directly dependent on the prevalence of the disease in a given patient cohort. Thus, the clinical value of a given test result is critically dependent on a precise indication. Ordering of tests that are not indicated in a given patient is clinically useless and undesirable, where detailed information on disease prevalence is missing. These considerations are valid irrespective of ethical or economic considerations.

Combined analysis of prenatal (maternal hair and blood) and neonatal (infant hair, cord blood and meconium) matrices to detect fetal exposure to environmental pesticides

OBJECTIVE

The aim of this study was to determine optimum biomarkers to detect fetal exposure to environmental pesticides by the simultaneous analysis of maternal (hair and blood) and infant (cord blood, infant hair or meconium) matrices and to determine if a combination of these biomarkers will further increase the detection rate.

PATIENTS AND METHODS

Pregnant women were prospectively recruited from an agricultural site in the Philippines with substantial use at home and in the farm of the following pesticides: propoxur, cyfluthrin, chlorpyrifos, cypermethrin, pretilachlor, bioallethrin, malathion, diazinon and transfluthrin. Maternal hair and blood were obtained at midgestation and at delivery and infant hair, cord blood and meconium were obtained after birth. All samples were analyzed by gas chromatography/mass spectrometry (GC/MS) for the above pesticides and some of their metabolites.

RESULTS

A total of 598 mother/infant dyads were included in this report. The highest rates of pesticide exposure were detected in meconium (23.2% to propoxur, 2.0% to pretilachlor, 1.7% to cypermethrin, 0.8% to cyfluthrin, 0.7% to 1,1,1-trichloro-2,2-bis, p-chlorophenylethane (DDT) and 0.3% to malathion and bioallethrin) and in maternal hair (21.6% to propoxur, 14.5% to bioallethrin, 1.3% to malathion, 0.8% to DDT, 0.3% to chlorpyrifos and 0.2% to pretilachlor). Combined analysis of maternal hair and meconium increased detection rate further to 38.5% for propoxur and to 16.7% for pyrethroids. Pesticide metabolites were rarely found in any of the analyzed matrices.

CONCLUSIONS

There is significant exposure of the pregnant woman and her fetus to pesticides, particularly to the home pesticides, propoxur and pyrethroids. Analysis of meconium for pesticides was the single most sensitive measure of exposure. However, combined analysis of maternal hair and meconium significantly increased the detection rate. A major advantage of analyzing maternal hair is that prenatal pesticide exposure in the mother can be detected and intervention measures can be initiated to minimize further exposure of the fetus to pesticides.

A comparison of infant hair, cord blood and meconium analysis to detect fetal exposure to environmental pesticides

OBJECTIVE

The detection of fetal exposure to environmental pesticides is important because many of the pesticides are neurotoxicants and fetal exposure to these compounds can adversely affect prenatal and subsequent neurodevelopment. The aim of this study was to determine, by the comparative analysis of infant hair, cord blood and meconium, the most sensitive matrix to detect fetal exposure to pesticides.

PATIENTS AND METHODS

Pregnant women were prospectively recruited from an agricultural site in the Philippines where a preliminary survey indicated a substantial use at home and in the farm of the following pesticides: propoxur, cyfluthrin, chlorpyrifos, cypermethrin, pretilachlor, bioallethrin, malathion, diazinon and transfluthrin. Infant hair, cord blood and meconium were obtained after birth and were analyzed by gas chromatography/mass spectrometry for the above compounds, including lindane and 1,1,1-trichloro-2,2-bis, p-chlorophenylethane (DDT) and some of their known metabolites.

RESULTS

A total of 638 infants were included in the study. The highest exposure rate to pesticides was detected in meconium (23.8% to propoxur, 1.9% to pretilachlor, 1.9% to cypermethrin, 0.8% to cyfluthrin, 0.6% to DDT and 0.3% to malathion and bioallethrin). Cord blood was only positive for propoxur (1.9%) whereas infant hair was only positive for chlorpyrifos (0.2%). The highest exposure was to household pesticide (propoxur). The frequency and concentration of pesticides were compared in the three matrices and there was a significantly higher frequency and concentration of propoxur, pretilachlor, DDT, cyfluthrin and cypermethrin in meconium compared to cord blood and infant hair. Pesticide metabolites were not found in any of the matrices analyzed, except in one meconium sample which was positive for 4,4' dichlorodiphenyldichloro ethylene (DDE), a DDT metabolite.

CONCLUSIONS

There is significant exposure of the pregnant woman and her fetus to pesticides, particularly to the home pesticide, propoxur. Our study has demonstrated that among cord blood, meconium or infant hair, meconium is the most sensitive matrix to analyze for fetal exposure to pesticides. The accumulation of pesticides in meconium, the ease of meconium collection and the large amount of meconium that could be collected are factors that contribute to the increased sensitivity of this matrix.

Prehospital point of care testing of blood gases and electrolytes - an evaluation of IRMA

BACKGROUND: This study evaluated the feasibility of blood gas analysis and electrolyte measurements during emergency transport prior to hospital admission. RESULTS: A portable, battery-powered blood analyzer was used on patients in life threatening conditions to determine pH, pCO2, pO2, sodium, potassium and ionized calcium. Arterial blood was used for blood gas analysis and electrolyte measurements. Venous blood was used for electrolyte measurement alone. During the observation period of 4 months, 32 analyses were attempted on 25 patients. Eleven measurements (34%) could not be performed due to technical failure. Overall, 25 samples taken from 21 patients were evaluated. The emergency physicians (all anesthesiologists) considered the knowledge of blood gases and/or electrolytes to be helpful in 72% of cases. This knowledge led to immediate therapeutic consequences in 52% of all cases. After a short training and familiarization session the handling of the device was found to be problem free. CONCLUSIONS: We concluded that knowledge of the patients' pH, pCO2 and pO2 in life threatening situations yields more objective information about oxygenation, carbon dioxide and acid-base regulation than pulse oximetry and/or capnometry alone. Additionally, it enables physicians to correct severe hypokalemia or hypocalcemia in cases of cardiac failure or malignant arrhythmia.