Folate concentrations and serum perfluoroalkyl and polyfluoroalkyl substance concentrations in adolescents and adults in the USA (National Health and Nutrition Examination Study 2003-16): an observational study.

BACKGROUND: Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a family of highly fluorinated aliphatic compounds, which are widely used in commercial applications, including food packaging, textiles, and non-stick cookware. Folate might counteract the effects of environmental chemical exposures. We aimed to explore the relationship between blood folate biomarker concentrations and PFAS concentrations. METHODS: This observational study pooled cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) 2003 to 2016 cycles. NHANES is a population-based national survey that measures the health and nutritional status of the US general population every 2 years by means of questionnaires, physical examination, and biospecimen collection. Folate concentrations in red blood cells and in serum, and perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS) concentrations in serum were examined. We used multivariable regression models to assess the percentage change in serum PFAS concentrations in relation to changes in folate biomarker concentrations. We additionally used models with restricted cubic splines to investigate the shape of these associations. FINDINGS: This study included 2802 adolescents and 9159 adults who had complete data on PFAS concentrations, folate biomarkers, and covariates, were not pregnant, and had never had a cancer diagnosis at the time of the survey. The mean age was 15·4 years (SD 2·3) for adolescents and 45·5 years (17·5) for adults. The proportion of male participants was slightly higher in adolescents (1508 [54%] of 2802 participants) than in adults (3940 [49%] of 9159 participants). We found negative associations between red blood cell folate concentrations and serum concentrations of PFOS (percentage change for a 2·7 fold-increase in folate level -24·36%, 95% CI -33·21 to -14·34) and PFNA (-13·00%, -21·87 to -3·12) in adolescents, and PFOA (-12·45%, -17·28 to -7·35), PFOS (-25·30%, -29·67 to -20·65), PFNA (-21·65%, -26·19 to -16·82), and PFHxS (-11·70%, -17·32 to 5·70) in adults. Associations for serum folate concentrations and PFAS were in line with those found for red blood cell folate levels, although the magnitude of the effects was lower. Restricted cubic spline models suggested linearity of the observed associations, particularly for associations in adults. INTERPRETATION: In this large-scale, nationally representative study, we found consistent inverse associations for most examined serum PFAS compounds in relation to folate concentrations measured in either red blood cells or serum among both adolescents and adults. These findings are supported by mechanistic in-vitro studies that show the potential of PFAS to compete with folate for several transporters implicated in PFAS toxicokinetics. If confirmed in experimental settings, these findings could have important implications for interventions to reduce the accumulated PFAS body burden and mitigate the related adverse health effects. FUNDING: United States National Institute of Environmental Health Sciences.

Male Age Influences Re-mating Incidence and Sperm Use in Females of the Dengue Vector Aedes aegypti.

Diseases transmitted by female Aedes aegypti mosquitoes are public health issues in countries in the tropics and sub-tropics. As in other insects, A. aegypti females undergo behavioral and physiological changes upon mating that principally act to facilitate the production of progeny. The primary effectors of A. aegypti female post-mating responses are male-derived seminal proteins that are transferred to females during mating. Increased male age reduces ejaculate function in numerous taxa and alters seminal protein composition in Drosophila melanogaster, but the impacts of male age on female A. aegypti post-mating responses are unknown. Here, we used "old" (21-22 days old) and "young" (4-5 days old) A. aegypti males to assess the influence of male age on oviposition, fertility, and re-mating incidence in their mates. We also examined how age influenced paternity share in females initially mated to young or old males that subsequently re-mated with a transgenic male that transferred RFP-labeled sperm and whose progeny inherited a larval-expressed GFP marker. We found that increased male age had no effect on female fecundity or fertility but significantly impacted their ability to prevent re-mating in their mates-more than half (54.5%) of the females mated to an old male re-mated, compared to 24% of females initially mated to a young male. Polyandrous A. aegypti females displayed first male precedence regardless of the age of their initial mate. However, young males were better able to compete with rival male sperm, siring significantly more progeny (77%) compared to old males (64%). Young males had significantly more sperm in their seminal vesicles than old males at the time of mating, although males of both age groups transferred similar numbers of sperm to their mates. Our results suggest that male senescence differentially impacts the induction of some post-mating changes in A. aegypti females. As the effect of age may be further exacerbated in the field, age-related declines in male ability to induce sexual refractoriness have implications for A. aegypti population control programs that release adults into the environment.

The role of maternal high fat diet on mouse pup metabolic endpoints following perinatal PFAS and PFAS mixture exposure.

Per- and polyfluoroalkyl substances (PFAS) are a family of chemicals that are ubiquitous in the environment. Some of these chemicals, such as perfluorooctanesulfonic acid (PFOS), perfluorohexanesulfonate (PFHxS) and perfluorooctanoic acid (PFOA), are found in human sera and have been shown to cause liver steatosis and reduce postnatal survival and growth in rodents. The purpose of this work is to evaluate the impact of diet and PFAS exposure to mouse dam (mus musculus) on the risk to pup liver and metabolism endpoints later in life, as well as evaluate PFAS partitioning to pups. Timed-pregnant dams were fed a standard chow diet or 60 % kcal high fat diet (HFD). Dams were administered either vehicle, 1 mg/kg PFOA, 1 mg/kg PFOS, 1 mg/kg PFHxS, or a PFAS mixture (1 mg/kg of each PFOA, PFOS, and PFHxS) daily via oral gavage from gestation day 1 until postnatal day (PND) 20. At PND 21, livers of dams and 2 pups of each sex were evaluated for lipid changes while remaining pups were weaned to the same diet as the dam for an additional 10 weeks. Dam and pup serum at PND 21 and PND 90 were also evaluated for PFAS concentration, alanine aminotransferase (ALT), leptin and adiponectin, and glycosylated hemoglobin A1c. Perinatal exposure to a HFD, as expected, increased pup body weight, maternal liver weight, pup liver triglycerides, pup serum ALT, and pup serum leptin. PFOA and the PFAS mixture increased liver weights, and. treatment with all three compounds increased liver triglycerides. The maternal HFD increased dam and pup serum PFAS levels, however, was protective against PFOA-induced increase in serum ALT and observed increases in liver triglycerides. The PFAS mixture had very distinct effects when compared to single compound treatment, suggesting some cumulative effects, particularly when evaluating PFAS transfer from dam to pup. This data highlights the importance of diet and mixtures when evaluating liver effect of PFAS and PFAS partitioning.

Spatial and temporal population dynamics of male and female Aedes albopictus at a local scale in Medellín, Colombia.

BACKGROUND: Diseases transmitted by invasive Aedes aegypti and Aedes albopictus mosquitoes are public health issues in the tropics and subtropics. Understanding the ecology of mosquito vectors is essential for the development of effective disease mitigation programs and will allow for accurate predictions of vector occurrence and abundance. Studies that examine mosquito population dynamics are typically focused on female presence or total adult captures without discriminating the temporal and spatial distribution of both sexes. METHODS: We collected immature and adult mosquitoes bimonthly for 2 years (2018-2019) in the Medellín Botanical Garden. Collection sites differed in proximity to buildings and nearby vegetation, and were classified by their overhead vegetation cover. We used linear mixed models (LMMs) and Spatial Analysis by Distance Indices (SADIE) to assess the spatial distribution of Ae. aegypti and Ae. albopictus. Using our Ae. albopictus captures exclusively, we assessed (1) the spatial and temporal distribution of males and females using SADIE and a generalized linear mixed model (GLMM), (2) the relationship between climatic variables/vegetation coverage and adult captures using GLMMs and LMMs, and (3) the correlation of male and female size in relation to climatic variables and vegetation coverage using LMMs. RESULTS: Spatial analysis showed that Ae. aegypti and Ae. albopictus were distributed at different locations within the surveilled area. However, Ae. albopictus was the predominant species in the park during the study period. Adult Ae. albopictus captures were positively correlated with precipitation and relative humidity, and inversely correlated with temperature and wind speed. Moreover, we observed a spatial misalignment of Ae. albopictus males and females-the majority of males were located in the high vegetation coverage sites, while females were more evenly distributed. We observed significant associations of the size of our adult Ae. albopictus captures with precipitation, temperature, and wind speed for both sexes and found that overhead vegetation cover influenced male size, but observed no effect on female size. CONCLUSIONS: Our work elucidates the differential dynamics of Ae. albopictus males and females, which is pivotal to develop accurate surveillance and the successful establishment of vector control programs based on the disruption of insect reproduction.

Hepatoprotective and anti-inflammatory effects of a standardized pomegranate (Punica granatum) fruit extract in high fat diet-induced obese C57BL/6 mice.

Diets rich in fats are linked to elevated systemic inflammation, which augments the progression of inflammatory-related disorders including non-alcoholic fatty liver disease (NAFLD) and neurodegenerative diseases. A phenolic-enriched pomegranate fruit extract (PE) was investigated for its hepatoprotective and anti-inflammatory effects in male C57BL/6 mice fed either a high-fat diet or a standard rodent diet with or without 1% of PE for 12 weeks. Mouse livers and hippocampi were evaluated for the expression of genes associated with NAFLD and inflammation by multiplexed gene analysis. PE alleviated diet-induced fatty liver and suppressed hepatic lipid regulating genes including Cd36, Fas, Acot2 and Slc27a1. In addition, PE suppressed gene expression of pro-inflammatory cytokines including Il-1α, Il-7, Il-11, Ifnα, Tnfα and Lepr in the hippocampi. Our findings support the protective effects of PE against high-fat diet-induced hepatic and neurological disease.

Promises and Challenges in Continuous Tracking Utilizing Amino Acids in Skin Secretions for Active Multi-Factor Biometric Authentication for Cybersecurity.

We consider a new concept of biometric-based cybersecurity systems for active authentication by continuous tracking, which utilizes biochemical processing of metabolites present in skin secretions. Skin secretions contain a large number of metabolites and small molecules that can be targeted for analysis. Here we argue that amino acids found in sweat can be exploited for the establishment of an amino acid profile capable of identifying an individual user of a mobile or wearable device. Individual and combinations of amino acids processed by biocatalytic cascades yield physical (optical or electronic) signals, providing a time-series of several outputs that, in their entirety, should suffice to authenticate a specific user based on standard statistical criteria. Initial results, motivated by biometrics, indicate that single amino acid levels can provide analog signals that vary according to the individual donor, albeit with limited resolution versus noise. However, some such assays offer digital separation (into well-defined ranges of values) according to groups such as age, biological sex, race, and physiological state of the individual. Multi-input biocatalytic cascades that handle several amino acid signals to yield a single digital-type output, as well as continuous-tracking time-series data rather than a single-instance sample, should enable active authentication at the level of an individual.

Bioaffinity-based assay for the sensitive detection and discrimination of sweat aimed at forensic applications.

Sweat is a well-known piece of biological evidence that is actually used much less than expected. Biological samples are important because their components can often provide some type of information about a person-of-interest. Sweat, in particular, is important because of its DNA content which can be extracted and analyzed to provide information that can be imperative to a criminal investigation. While it is a very important source of forensic information, the methods for detection and discrimination of sweat are limited, causing it to be overlooked during evidence collection. This manuscript presents a biocatalytic method for sweat detection that utilizes an enzyme cascade system that has the capability to detect trace amounts of sweat and distinguish it from saliva, even after the sample has dried. The results show the initial calibration studies performed to insure that the cascade performs well using both mimicked and authentic sweat samples which have components that could negatively affect the enzymes needed for the analysis. The method presented here also has the potential to be adapted for on-site analysis. The initial results of the development of a sweat-sensitive strip are shown here.

Coomassie Brilliant Blue G-250 Dye: An Application for Forensic Fingerprint Analysis.

The Bradford reagent, comprised of the Coomassie Brilliant Blue G-250 dye, methanol, and phosphoric acid, has been traditionally used for quantifying proteins. Use of this reagent in the Bradford assay relies on the binding of the Coomassie Blue G-250 dye to proteins. However, the ability of the dye to react with a small group of amino acids (arginine, histidine, lysine, phenylalanine, tyrosine, and tryptophan) makes it a viable chemical assay for fingerprint analysis in order to identify the biological sex of the fingerprint originator. It is recognized that the identification of biological sex has been readily accomplished using two other methods; however, both of those systems are reliant upon a large group of amino acids, 23 to be precise. The Bradford assay, described here, was developed specifically to aid in the transition from targeting large groups of amino acids, as demonstrated in the previous studies, to targeting only a single amino acid without compromising the intensity of the response and/or the ability to differentiate between two attributes. In this work, we aim to differentiate between female fingerprints and male fingerprints.

Ages at a Crime Scene: Simultaneous Estimation of the Time since Deposition and Age of Its Originator.

Blood is a major contributor of evidence in investigations involving violent crimes because of the unique composition of proteins and low molecular weight compounds present in the circulatory system, which often serve as biomarkers in clinical diagnostics. It was recently shown that biomarkers present in blood can also identify characteristics of the originator, such as ethnicity and biological sex. A biocatalytic assay for on-site forensic investigations was developed to simultaneously identify the age range of the blood sample originator and the time since deposition (TSD) of the blood spot. For these two characteristics to be identified, the levels of alkaline phosphatase (ALP), a marker commonly used in clinical diagnostics corresponding to old and young originators, were monitored after deposition for up to 48 h to mimic a crime scene setting. ALP was chosen as the biomarker due to its age-dependent nature. The biocatalytic assay was used to determine the age range of the originator using human serum samples. By means of statistical tools for evaluation and the physiological levels of ALP in healthy people, the applicability of this assay in forensic science was shown for the simultaneous determination of the age of the originator and the TSD of the blood spot. The stability of ALP in serum allows for the differentiation between old and young originators up to 2 days after the sample was left under mimicked crime scene conditions.

New Horizons for Ninhydrin: Colorimetric Determination of Gender from Fingerprints.

In the past century, forensic investigators have universally accepted fingerprinting as a reliable identification method via pictorial comparison. One of the most traditional detection methods uses ninhydrin, a chemical that reacts with amino acids in the fingerprint content to produce the blue-purple color known as Ruhemann's purple. It has recently been demonstrated that the amino acid content in fingerprints can be used to differentiate between male and female fingerprints. Here, we present a modified approach to the traditional ninhydrin method. This new approach for using ninhydrin is combined with an optimized extraction protocol and the concept of determining gender from fingerprints. In doing so, we are able to focus on the biochemical material rather than exclusively the physical image.

Forensic Identification of Gender from Fingerprints.

In the past century, forensic investigators have universally accepted fingerprinting as a reliable identification method, which relies mainly on pictorial comparisons. Despite developments to software systems in order to increase the probability and speed of identification, there has been limited success in the efforts that have been made to move away from the discipline's absolute dependence on the existence of a prerecorded matching fingerprint. Here, we have revealed that an information-rich latent fingerprint has not been used to its full potential. In our approach, the content present in the sweat left behind-namely the amino acids-can be used to determine physical such as gender of the originator. As a result, we were able to focus on the biochemical content in the fingerprint using a biocatalytic assay, coupled with a specially designed extraction protocol, for determining gender rather than focusing solely on the physical image.

Forensic determination of blood sample age using a bioaffinity-based assay.

A bioaffinity-driven cascade assay was developed to determine the time elapsed from the point a blood sample was left at a crime scene to the point of discovery. Two blood markers, creatine kinase (CK) and alanine transaminase (ALT), were utilized to determine the age of the blood spot based on their natural denaturation processes. The analysis with the proposed bioassay was performed in human serum samples, which underwent the aging process under environmental conditions that could be expected at crime scenes. The concentration of the markers in the sample was based on physiological levels present in healthy adults. These two markers were concerted in a biocatalytic cascade composed of two parallel subsystems, with each of them following the activity of one marker. Both markers have very distinct denaturation rates which would not allow them to be used in a single marker setup while still providing satisfactory results. However, by parallel tunable monitoring of both markers, it is possible to provide information of the blood sample age with low temporal error for a prolonged period of time. To mimic a possible real crime scene situation ­ the reliability of the proposed assay was then successfully tested on dried/aged serum samples (up to 5 days old) in environments with different temperatures.