Efficacy of moxidectin, using various dose regimens, against JYD-34, a macrocyclic lactone resistant isolate of Dirofilaria immitis

BACKGROUND

Macrocyclic lactones (MLs) are the only class of drugs currently commercially available that are effective for preventing heartworm disease. The data presented in this article provide information on the efficacy of oral moxidectin against JYD-34, a known ML-resistant Dirofilaria immitis isolate, when dogs are treated under various dosing regimens.

METHODS

Fifty-two purpose-bred Beagle dogs were used in five laboratory studies. All dogs were inoculated with 50 D. immitis third-stage larvae (L3) (JYD-34 isolate) 30 days prior to the first treatment. Dogs were randomized to treatment (four to five animals in each group) with one, three, or five monthly doses of oral moxidectin ranging from 6 to 100 µg/kg body weight. In each study, control dogs were not treated. Five to 6 months after L3 inoculation, dogs were euthanized, and adult worms were counted to evaluate efficacy of the dosing regimens.

RESULTS

Adult heartworms were recovered from all control dogs, with an overall geometric mean of 29.7 worms (range 15.2 to 38.0, individual counts ranged from 8 to 51). Five monthly doses of 6 µg/kg provided 83.3% and 90.2%, efficacy, and the same number of monthly doses of 9 µg/kg demonstrated 98.8% and 94.1% efficacy. Three monthly doses of 30 and 50 µg/kg demonstrated 97.9% and 99.0% efficacy, respectively, while a single dose of 100 µg/kg demonstrated 91.1% efficacy.

CONCLUSIONS

Five monthly doses of 9 µg/kg provided similar or only marginally lower efficacy against JYD-34, a known ML-resistant isolate, compared to substantially higher doses administered for 3 months. This underscores the importance of duration of exposure to moxidectin when facing ML-resistant isolates. Repeated administration of lower doses of moxidectin are an alternative to higher doses in the prevention of heartworm disease associated with less susceptible or resistant isolates.

Epithelial MAPK signaling directs endothelial NRF2 signaling and IL-8 secretion in a tri-culture model of the alveolar-microvascular interface following diesel exhaust particulate (DEP) exposure

BACKGROUND

Particulate matter 2.5 (PM2.5) deposition in the lung's alveolar capillary region (ACR) is significantly associated with respiratory disease development, yet the molecular mechanisms are not completely understood. Adverse responses that promote respiratory disease development involve orchestrated, intercellular signaling between multiple cell types within the ACR. We investigated the molecular mechanisms elicited in response to PM2.5 deposition in the ACR, in an in vitro model that enables intercellular communication between multiple resident cell types of the ACR.

METHODS

An in vitro, tri-culture model of the ACR, incorporating alveolar-like epithelial cells (NCI-H441), pulmonary fibroblasts (IMR90), and pulmonary microvascular endothelial cells (HULEC) was developed to investigate cell type-specific molecular responses to a PM2.5 exposure in an in-vivo-like model. This tri-culture in vitro model was termed the alveolar capillary region exposure (ACRE) model. Alveolar epithelial cells in the ACRE model were exposed to a suspension of diesel exhaust particulates (DEP) (20 µg/cm2) with an average diameter of 2.5 µm. Alveolar epithelial barrier formation, and transcriptional and protein expression alterations in the directly exposed alveolar epithelial and the underlying endothelial cells were investigated over a 24 h DEP exposure.

RESULTS

Alveolar epithelial barrier formation was not perturbed by the 24 h DEP exposure. Despite no alteration in barrier formation, we demonstrate that alveolar epithelial DEP exposure induces transcriptional and protein changes in both the alveolar epithelial cells and the underlying microvascular endothelial cells. Specifically, we show that the underlying microvascular endothelial cells develop redox dysfunction and increase proinflammatory cytokine secretion. Furthermore, we demonstrate that alveolar epithelial MAPK signaling modulates the activation of NRF2 and IL-8 secretion in the underlying microvascular endothelial cells.

CONCLUSIONS

Endothelial redox dysfunction and increased proinflammatory cytokine secretion are two common events in respiratory disease development. These findings highlight new, cell-type specific roles of the alveolar epithelium and microvascular endothelium in the ACR in respiratory disease development following PM2.5 exposure. Ultimately, these data expand our current understanding of respiratory disease development following particle exposures and illustrate the utility of multicellular in vitro systems for investigating respiratory tract health.

Liquid application dosing alters the physiology of air-liquid interface (ALI) primary human bronchial epithelial cell/lung fibroblast co-cultures and in vitro testing relevant endpoints

Differentiated primary human bronchial epithelial cell (dpHBEC) cultures grown under air-liquid interface (ALI) conditions exhibit key features of the human respiratory tract and are thus critical for respiratory research as well as efficacy and toxicity testing of inhaled substances (e.g., consumer products, industrial chemicals, and pharmaceuticals). Many inhalable substances (e.g., particles, aerosols, hydrophobic substances, reactive substances) have physiochemical properties that challenge their evaluation under ALI conditions in vitro. Evaluation of the effects of these methodologically challenging chemicals (MCCs) in vitro is typically conducted by "liquid application," involving the direct application of a solution containing the test substance to the apical, air-exposed surface of dpHBEC-ALI cultures. We report that the application of liquid to the apical surface of a dpHBEC-ALI co-culture model results in significant reprogramming of the dpHBEC transcriptome and biological pathway activity, alternative regulation of cellular signaling pathways, increased secretion of pro-inflammatory cytokines and growth factors, and decreased epithelial barrier integrity. Given the prevalence of liquid application in the delivery of test substances to ALI systems, understanding its effects provides critical infrastructure for the use of in vitro systems in respiratory research as well as in the safety and efficacy testing of inhalable substances.

Beadchip technology to detect DNA methylation in mouse faithfully recapitulates whole-genome bisulfite sequencing

Aim: To facilitate wide-scale implementation of Illumina Mouse Methylation BeadChip (MMB) technology, array-based measurement of cytosine methylation was compared with the gold-standard assessment of DNA methylation by whole-genome bisulfite sequencing (WGBS). Methods: DNA methylation across two mouse strains (C57B6 and C3H) and both sexes was assessed using the MMB and compared with previously existing deep-coverage WGBS of mice of the same strain and sex. Results & conclusion: The findings demonstrated that 93.3-99.2% of sites had similar measurements of methylation across technologies and that differentially methylated cytosines and regions identified by each technology overlap and enrich for similar biological functions, suggesting that the MMB faithfully recapitulates the findings of WGBS.

Liquid Application Dosing Alters the Physiology of Air-Liquid Interface Primary Bronchial Epithelial Cultures and In vitro Testing Relevant Endpoints

Differentiated Primary human bronchial epithelial cell (dpHBEC) cultures grown under air-liquid interface (ALI) conditions exhibit key features of the human respiratory tract and are thus critical for respiratory research as well as efficacy and toxicity testing of inhaled substances (e.g., consumer products, industrial chemicals, and pharmaceuticals). Many inhalable substances (e.g., particles, aerosols, hydrophobic substances, reactive substances) have physiochemical properties that challenge their evaluation under ALI conditions in vitro. Evaluation of the effects of these methodologically challenging chemicals (MCCs) in vitro is typically conducted by "liquid application," involving the direct application of a solution containing the test substance to the apical, air-exposed surface of dpHBEC-ALI cultures. We report that the application of liquid to the apical surface of a dpHBEC-ALI co-culture model results in significant reprogramming of the dpHBEC transcriptome and biological pathway activity, alternative regulation of cellular signaling pathways, increased secretion of pro-inflammatory cytokines and growth factors, and decreased epithelial barrier integrity. Given the prevalence of liquid application in the delivery of test substances to ALI systems, understanding its effects provides critical infrastructure for the use of in vitro systems in respiratory research as well as in the safety and efficacy testing of inhalable substances.

High-fat diet aggravates prenatal low-dose DEHP exposure induced spermatogenesis disorder: Characterization of testicular metabolic patterns in mouse offspring

Di-(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer and has been identified as a male prenatal reproductive toxicant. A high fat diet (HFD) has also been suggested as another potential disruptor of male reproductive function. Despite this potential synergism between DEHP exposure and HFD, little is known about the concomitant effects of prenatal DEHP and a subsequent HFD exposure on male offspring reproductive injury. Here we established a mouse model of prenatal exposure to DEHP (0.2 mg/kg/day) to assess the testicular development and spermatogenesis in offspring subjected to obesogenic diet during the pubertal period. Gross phenotype, hormone profiles and the testicular metabolome were analyzed to determine the underlying mechanism. We found that prenatal exposure to low-dose DEHP resulted in decreased sperm density, decreased testosterone (T) levels, increased luteinizing hormone (LH) levels and testicular germ cell apoptosis. Furthermore, these injury phenotypes were aggravated by pubertal HFD treatment. Testicular riboflavin and biotin metabolites were enriched implying their roles in contributing HFD to exacerbate offspring spermatogenesis disorders due to prenatal low-dose DEHP exposure. Our findings suggest that pubertal HFD exacerbates reproductive dysfunction associated with prenatal exposure to low-dose DEHP in male adult offspring.

Prothioconazole induces cell cycle arrest by up-regulation of EIF4EBP1 in extravillous trophoblast cells

Prothioconazole (PTC) is a new broad-spectrum triazole antibacterial agent that is being widely used in agriculture. PTC has been linked to a number of reproductive outcomes including embryo implantation disorder; however, the exact mechanism underlying this relationship has yet to be determined. Proper trophoblast proliferation and migration is a prerequisite for successful embryo implantation. To elucidate the underlying molecular perturbations, we detect the effect of PTC on extravillous trophoblast cells proliferation and migration, and investigate its potential mechanisms. Exposure to different concentrations of PTC (0-500 μM) significantly inhibited the cell viability and migration ability (5 μM PTC exposure), and also caused the cell cycle arrest at the lowest dose (1 μM PTC exposure). Transcriptome analysis revealed that PTC exposure disturbed multiple biological processes including cell cycle and apoptosis, consistent with cell phenotype. Specifically, eukaryotic translation initiation factor 4E binding protein 1 (EIF4EBP1, 4E-BP1) was identified as up-regulated in PTC exposure group and knockdown of EIF4EBP1, and attenuated the G1 phase arrest induced by PTC exposure. In summary, our data demonstrated that 4E-BP1 participated in PTC-induced cell cycle arrest in extravillous trophoblast cells by regulating cyclin D1. These findings shed light on the potential adverse effect of PTC exposure on the embryo implantation.

Ozone Responsive Gene Expression as a Model for Describing Repeat Exposure Response Trajectories and Interindividual Toxicodynamic Variability In Vitro

Inhaled chemical/material exposures are a ubiquitous part of daily life around the world. There is a need to evaluate potential adverse effects of both single and repeat exposures for thousands of chemicals and an exponentially larger number of exposure scenarios (eg, repeated exposures). Meeting this challenge will require the development and use of in vitro new approach methodologies (NAMs); however, 2 major challenges face the deployment of NAMs in risk assessment are (1) characterizing what apical outcome(s) acute assays inform regarding the trajectory to long-term events, especially under repeated exposure conditions, and (2) capturing interindividual variability as it informs considerations of potentially susceptible and/or vulnerable populations. To address these questions, we used a primary human bronchial epithelial cell air-liquid interface model exposed to ozone (O3), a model oxidant and ubiquitous environmental chemical. Here we report that O3-induced proinflammatory gene induction is attenuated in repeated exposures thus demonstrating that single acute exposure outcomes do not reliably represent the trajectory of responses after repeated or chronic exposures. Further, we observed 10.1-, 10.3-, 14.2-, and 7-fold ranges of induction of interleukin (IL)-8, IL-6, heme oxygenase 1, and cyclooxygenase 2 transcripts, respectively, within in our population of 25 unique donors. Calculation of sample size estimates that indicated that 27, 24, 299, and 13 donors would be required to significantly power similar in vitro studies to identify a 2-fold change in IL-8, IL-6, HMOX1, and cyclooxygenase 2 transcript induction, respectively, to inform considerations of the uncertainty factors to reflect variability within the human population for in vitro studies.

Directed movement toward, translocation along, penetration into and exit from vascular networks by breast cancer cells in 3D

We developed a computer-assisted platform using laser scanning confocal microscopy to 3D reconstruct in real-time interactions between metastatic breast cancer cells and human umbilical vein endothelial cells (HUVECs). We demonstrate that MB-231 cancer cells migrate toward HUVEC networks, facilitated by filopodia, migrate along the network surfaces, penetrate into and migrate within the HUVEC networks, exit and continue migrating along network surfaces. The system is highly amenable to 3D reconstruction and computational analyses, and assessments of the effects of potential anti-metastasis monoclonal antibodies and other drugs. We demonstrate that an anti-RHAMM antibody blocks filopodium formation and all of the behaviors that we found take place between MB-231 cells and HUVEC networks.

The estrogen receptor/GATA3/FOXA1 transcriptional network: lessons learned from breast cancer

Cellular identity and physiologic function in mammary epithelial cells and in many breast cancers flow from the action of a network of master transcriptional regulators including estrogen receptor alpha, GATA3, and FOXA1. The last decade has seen the completion of multiple large sequencing projects focusing on breast cancer. These massive compendia of sequence data have provided a wealth of new information linking mutation in these transcription factors to alterations in tumor biology and transcriptional program. The emerging details on mutation in cancer, and direct experimental exploration of hypotheses based on it, are now providing a wealth of new information on the roles played by estrogen receptor alpha, GATA3, and FOXA1 in regulating gene transcription and how their combined action contributes to a network shaping cell function in both physiologic and disease states.

Environmental Factors Involved in Maternal Morbidity and Mortality

Nongenetic, environmental factors contribute to maternal morbidity and mortality through chemical exposures via air, water, soil, food, and consumer products. Pregnancy represents a particularly sensitive window of susceptibility during which physiological changes to every major organ system increase sensitivity to chemicals that can impact a woman's long-term health. Nonchemical stressors, such as low socioeconomic status, may exacerbate the effects of chemical exposures on maternal health. Racial/ethnic minorities are exposed disproportionately to both chemicals and nonchemical stressors, which likely contribute to the observed health disparities for maternal morbidities and mortality. Epidemiological studies linking exposures to adverse maternal health outcomes underscore the importance of environmental health impacts, and mechanistic studies in model systems reveal how chemicals perturb biological pathways and processes. Environmental stressors are associated with a variety of immediate maternal health impacts, including hypertensive disorders of pregnancy, fibroids, and infertility, as well as long-term maternal health impacts, such as higher risk of breast cancer and metabolic disorders. Identifying and reducing a pregnant woman's environmental exposures is not only beneficial to her offspring but also important to preserve her short- and long-term health.

Physicochemical properties of soy protein hydrolysate and its formulation and stability with encapsulated probiotic under in vitro gastrointestinal environment

The objective of this study was to prepare protein isolate from defatted soybean and identify an optimal hydrolysis protocol to create improved hydrolysates and ascertain the optimum encapsulation technique for probiotics. Soy protein isolate (SPI) was prepared using an alkaline extraction procedure for solubility within a neutral, beverage-specific pH range. The soy protein hydrolysate (SPH) was prepared from aqueous extracted SPI using pepsin. The physicochemical properties of the SPH were investigated by solubility, degree of hydrolysis (DH), surface hydrophobicity, and electrophoresis. Hydrolysates from 2, 2.5, and 3 hr of hydrolysis time achieved the suitable DH between 2.5% to 5.0%. The 2.5 to 3 hr hydrolysates were also significantly more soluble than SPI at all pH levels from 85% to 95% solubility. Surface hydrophobicity of the hydrolysates ranged from 15 to 20 S0 values. Alginate (1%), resistant starch (2%), and probiotic culture (0.1%) were used as an encapsulation agent to protect probiotics. Alginate microcapsules were observed to be 1 mm in size using environmental scanning electron microscopy. The dried SPH and encapsulated probiotics with alginate in a dry powder formulation were tested for its gastrointestinal resistance and probiotic viability under in vitro simulated digestion. Approximately 1-log decrease was observed for all experimental groups after simulated digestion (final log colony forming units [CFU]/mL range: 6.55 to 6.19) with free probiotics having the lowest log CFU/mL (6.10 ± 0.10) value. No significant difference was observed among experimental groups for probiotic viability (P = 0.445). The findings of this research will provide an understanding of formulation for easily digestible protein and encapsulated probiotics. PRACTICAL APPLICATION: The findings of this research provide an understanding of improved formulation for more suitable soy protein hydrolysate and viability of encapsulated probiotics in gastrointestinal environment. Probiotics with the prebiotics in an encapsulated environment provide a technology for the enhancement of probiotics viability and for applications in suitable products for health and wellness.

Using a Faculty-Developed Documentary-Style Film to Communicate Authentic Chemistry Research to a High School Audience

Described is the creation, deployment, and evaluation of a video produced about the synthesis and applications of metal-organic frameworks (MOFs). The goal of this project was to gauge the impact of viewing the video on high school students' conceptions of authentic chemistry practices and applications. Additionally, comparisons were made between the use of the video and more traditional face-to-face presentations given by professional scientists. Observations, student surveys, and an interview with the high school chemistry teacher demonstrated the utility of such a video. Specifically, the students who viewed the video reported learning more about the nature of laboratory work in chemistry than other students who did not view the video. Students, regardless of whether they viewed the video or just received a presentation, reported growth in understandings of the applications of chemistry research and porous nanomaterial. Other research chemists are encouraged to consider ways that they could document on video the research that they are performing in order to introduce an untapped audience (high school students) to authentic chemistry research in a practically simple manner. During times of crisis, such as a pandemic, online videos could be a useful tool for high school chemistry teachers to use in collaboration with research faculty, particularly when schools are closed.

Wood Smoke Exposure Alters Human Inflammatory Responses to Viral Infection in a Sex-Specific Manner. A Randomized, Placebo-controlled Study

RATIONALE

Exposure to particulates from burning biomass is an increasing global health issue. Burning biomass, including wood smoke, is associated with increased lower respiratory infections.

OBJECTIVES

To determine whether acute exposure to wood smoke modifies nasal inflammatory responses to influenza.

METHODS

Healthy young adults (n = 39) were randomized to a 2-hour controlled chamber exposure to wood smoke, where exposure levels were controlled to particulate number (wood smoke particles [WSP]; 500 μg/cm³) or filtered air, followed by nasal inoculation with a vaccine dose of live attenuated influenza virus (LAIV). Nasal lavage was performed before exposure (Day 0) and on Days 1 and 2 after exposure. Nasal lavage fluid cells were analyzed for inflammatory gene expression profiles, and cell-free fluid was assayed for cytokines.

MEASUREMENTS AND MAIN RESULTS

Only IP-10 protein levels were affected, suppressed, by WSP exposure in aggregate analysis. Subsequent analysis indicated an exposure × sex interaction, prompting additional analyses of WSP- and LAIV-induced changes in males and females. Inflammation-related gene expression profiles differed between the sexes, at baseline (males greater than females), after LAIV inoculation (females greater than males), and after WSP exposure (increase in males and decrease in females), demonstrating that WSP- and LAIV-induced changes in antiviral defense responses in the nasal mucosa occur in a sex-specific manner.

CONCLUSIONS

WSP exposure resulted in minimal modification of LAIV-induced responses in aggregate analysis. In contrast, analyzing WSP-induced modification of LAIV responses in the sexes separately unmasked sex-specific differences in response to exposure. These data highlight the need for additional studies to understand sex-specific pollutant-induced effects. Clinical trial registered with www.clinicaltrials.gov (NCT02183753).

Epigenome-wide DNA methylation in placentas from preterm infants: association with maternal socioeconomic status

This study evaluated the hypothesis that prenatal maternal socioeconomic status (SES) adversity is associated with DNA methylation in the placenta. SES adversity was defined by the presence of, as well as a summative count of, four factors: less than college education, single marital status, food and nutritional service assistance, and public health insurance. Epigenome-wide DNA methylation was assessed using the Illumina EPIC array in 426 placentas from a sample of infants born < 28 weeks of gestation from the Extremely Low Gestational Age Newborn cohort. Associations between SES adversity and DNA methylation were assessed with robust linear regressions adjusted for covariates and controlled the false discovery rate at < 10%. We also examined whether such associations were sex specific. Indicators of SES adversity were associated with differential methylation at 33 CpG sites. Of the 33 identified CpG sites, 19 (57.6%) displayed increased methylation, and 14 (42.4%) displayed decreased methylation in association with at least one of the SES adversity factors. Sex differences were observed in DNA methylation associated with summative SES score; in which placentas derived from female pregnancies showed more robust differential CpG methylation than placentas from male pregnancies. Maternal SES adversity was associated with differential methylation of genes with key role in gene transcription and placental function, potentially altering immunity and stress response. Further investigation is needed to evaluate the role of epigenetic differences in mediating the association between maternal socioeconomic status during pregnancy and later life health outcomes in children.

Evaluation of Bone Marrow Adipose Tissue and Bone Mineralization on Broiler Chickens Affected by Wooden Breast Myopathy

In humans, alterations in bone metabolism have been associated with myopathies. We postulate the hypothesis that perhaps similar pathologies can also be associated in modern chickens. Hence, this study aimed to assess the fat infiltration in bone marrow and its repercussion on broiler chicken affected by Wooden Breast (WB) myopathy. Ten Cobb 500 live birds with extreme rigidity of the Pectoralis major (PM) muscle were selected as WB affected chickens by physical examination of the muscle at 49 days of age, whereas ten chickens healthy with no physical signs of hardness in the breast muscle were considered to be unaffected. Macroscopic lesions in affected chickens included areas of firm and inflamed muscle with pale appearance, hemorrhaging, and viscous exudate on the surface. Bone marrow and sections of the PM muscle were collected and analyzed for light microscopy. Additionally, transmission electron microscopy was conducted in affected or unaffected muscle. Chickens affected with WB showed significant reductions (P < 0.05) in femur diameter, calcium, and phosphorous percentage but increased breast weight, compression force and filet thickness when compared with non-affected chickens. Interestingly, bone marrow from WB chicken had subjectively, more abundant infiltration of adipose tissue, when compared with non-affected chickens. Histology of the Pectoralis major of birds with WB showed abundant infiltration of adipose tissue, muscle fibers degeneration with necrosis and infiltration of heterophils and mononuclear cells, connective tissue proliferation, and vasculitis. Ultrastructural changes of WB muscle revealed lack definition of bands in muscle tissue, or any normal ultrastructural anatomy such as myofibrils. The endomysium components were necrotic, and in some areas, the endomysium was notable only as a string of necrotic tissue between degraded myofibrils. The fascia appeared hypertrophied, with large areas of necrosis and myofiber without structural identity with degraded mitochondria adjacent to the disrupted muscle tissue. As far as we know, this is the first study that describes a subjective increase in adipose tissue in the bone marrow of chickens affected with WB when compared with non-affected chickens, and reduced bone mineralization.

Inorganic Arsenic as an Endocrine Disruptor: Modulation of the Glucocorticoid Receptor Pathway in Placental Cells via CpG Methylation

Prenatal exposure to inorganic arsenic (iAs) has been associated with adverse developmental and reproductive outcomes. These outcomes may be tied to altered functionality of nuclear transcription factors such as the glucocorticoid receptor (GR) in the placenta and associated gene expression. The GR pathway is integral for proper fetal and placental development, and perturbations in this pathway may underlie observed associations between prenatal iAs exposure and adverse birth outcomes. We therefore set out to investigate whether iAs modulates the GR signaling pathway in placental cells. JEG-3 trophoblasts were exposed to environmentally-relevant doses of iAs, and mRNA expression assessed. To examine the links between iAs exposure, the GR signaling pathway, and epigenetic modification, DNA methylation levels were also quantified. Treatment with iAs altered the expression of 12 GR-genes that play a role in fetal and placental development. Furthermore, at a gene-specific level, mRNA abundance was associated with changes in DNA methylation patterning in JEG-3 cells, suggesting that the effects of iAs are mediated by epigenetic mechanisms. The identified target genes have been associated with prenatal iAs exposure, placental physiology, and fetal development. This study provides further evidence for iAs as an endocrine disruptor and provides insight as to the mechanisms by which prenatal iAs exposure may induce adverse birth outcomes.

Discrimination exposure and DNA methylation of stress-related genes in Latina mothers

Latina mothers, who have the highest fertility rate among all ethnic groups in the US, are often exposed to discrimination. The epigenetic changes related to this discrimination are largely unknown. This study is the first to explore the relationship between discrimination and DNA methylation of stress regulatory genes in Latinas. Our sample was Latina women (n = 147) with a mean age of 27.6 years who were assessed at 24-32 weeks' gestation (T1) and 4-6 weeks postpartum (T2) and reside in the U.S. Blood was collected at T1, and the Everyday Discrimination Scale (EDS) was administered at T1 and T2. DNA Methylation at candidate gene regions was determined by bisulphite pyrosequencing. Associations between EDS and DNA methylation were assessed via zero-inflated Poisson models, adjusting for covariates and multiple-test comparisons. Discrimination was negatively associated with methylation at CpG sites within the glucocorticoid receptor (NR3C1) and brain-derived neurotrophic factor (BDNF) genes that were consistent over time. In addition, discrimination was negatively associated with methylation of a CpG in the glucocorticoid binding protein (FKBP5) at T1 but not at T2. This study underscores associations between discrimination and epigenetic markers of DNA methylation in Latinas that warrant further investigation to better understand the biological pathways and psychopathological effects of discrimination on Latina mothers and their families.

Toxic metals in amniotic fluid and altered gene expression in cell-free fetal RNA

Both exposures to toxic metals, as well as deficiencies in essential metals, during pregnancy has been linked to a variety of negative reproductive outcomes. The exact etiologies of such outcomes and the effects of fetal exposure to these metals are largely unknown. Therefore, the ability to assess levels of these elements is critical to determining the underlying causes of such conditions and the effects that both essential and nonessential metals have on fetal development. Thus, using cell-free fetal RNA from amniotic fluid, we set out to measure the association between amniotic fluid levels of toxic and essential metals and fetal gene expression. We find that arsenic was associated with increased expression of 3 genes known to play roles in both birth-related and reproductive effects. The results highlight the potential for detrimental health effects of prenatal metals exposure and the potential to identify biomarkers of environmental exposure during this critical developmental period.

Placental CpG methylation of HPA-axis genes is associated with cognitive impairment at age 10 among children born extremely preterm

A major component of the neuroendocrine system is the hypothalamus-pituitary adrenal (HPA) axis. HPA axis genes are also known to play a role in placental physiology. Thus, disruptions in the signaling of HPA axis-associated genes may adversely impact the placenta as well as fetal development, with adverse consequences for health and development of the child. In support of this, recent studies have shown that placental epigenetic methylation of HPA axis genes has an impact on infant behavior. In this study, we evaluated CpG methylation of 14 placental HPA axis-associated genes from a subcohort (n=228) of the Extremely Low Gestational Age Newborns (ELGAN) cohort in relation to cognitive function in mid-childhood (e.g. 10 yrs). Multivariable logistic regression revealed that placental CpG methylation of 10 HPA-axis associated genes were significantly associated with cognition at age 10. Specifically, placental CpG methylation levels of the glucocorticoid receptor gene, Nuclear Receptor Subfamily Group 3 C Member 1 (NR3C1) and Brain-derived Neurotropic Factor (BDNF) were significantly associated with increased odds in developing moderate/severe adverse cognitive impairment at age 10. Methyl-CpG Binding Protein 2 (MECP2) was the major transcriptional regulator of the ten identified HPA genes. The data suggest that placental CpG methylation is associated with cognitive outcomes in mid-childhood.

Distinguishing Human Peripheral Blood NK Cells from CD56dimCD16dimCD69+CD103+ Resident Nasal Mucosal Lavage Fluid Cells

Natural killer (NK) cells are members of the innate lymphoid cells group 1 (ILC1s), which play a critical role in innate host defense against viruses and malignancies. While many studies have examined the role of circulating peripheral blood (PB) CD56⁺ NK cells, little is known about the resident CD56⁺ cell population. Therefore, matched CD56⁺ cells from nasal lavage fluid (NLF) and PB of smokers and non-smokers were compared phenotypically, via flow cytometry, and functionally, via NK-cell specific gene expression. NLF and PB CD56⁺ cells had similar expression of CD56, but differentially expressed tissue residency (CD69 and CD103) and cytotoxicity (CD16) markers. In addition, NLF CD56^dim cells expressed lower levels of cytotoxicity-associated genes, perforin (PRF1) and granzyme B (GZMB), and increased levels of cytokines and cell signaling molecules, TRAIL, IFNGR2, and IL8, as compared to PB CD56^dim cells. In smokers, ITGA2 was downregulated in NLF CD56^dim cells, while markers of cytotoxic function were primarily downregulated in PB CD56^dim NK cells. Overall, NLF CD56^dim cells are a unique cell population that likely play a role in orchestrating innate immune responses in the nasal cavity, which is distinct from their role as a non-antigen-restricted cytotoxic CD56^dim lymphocytes in the PB.

Environmental Influences on the Epigenome: Exposure- Associated DNA Methylation in Human Populations

DNA methylation is the most well studied of the epigenetic regulators in relation to environmental exposures. To date, numerous studies have detailed the manner by which DNA methylation is influenced by the environment, resulting in altered global and gene-specific DNA methylation. These studies have focused on prenatal, early-life, and adult exposure scenarios. The present review summarizes currently available literature that demonstrates a relationship between DNA methylation and environmental exposures. It includes studies on aflatoxin B₁, air pollution, arsenic, bisphenol A, cadmium, chromium, lead, mercury, polycyclic aromatic hydrocarbons, persistent organic pollutants, tobacco smoke, and nutritional factors. It also addresses gaps in the literature and future directions for research. These gaps include studies of mixtures, sexual dimorphisms with respect to environmentally associated methylation changes, tissue specificity, and temporal stability of the methylation marks.

Microorganisms in the human placenta are associated with altered CpG methylation of immune and inflammation-related genes

Microorganisms in the placenta have been linked to adverse pregnancy outcomes as well as neonatal illness. Inflammation in the placenta has been identified as a contributing factor in this association, but the underlying biological mechanisms are not yet fully understood. The placental epigenome may serve as an intermediate between placental microbes and inflammation, contributing to adverse outcomes in the offspring. In the present study, genome-wide DNA methylation (n = 486,428 CpG sites) of 84 placentas was analyzed in relation to 16 species of placental microorganisms using samples collected from the Extremely Low Gestation Age Newborns (ELGAN) cohort. A total of n = 1,789 CpG sites, corresponding to n = 1,079 genes, displayed differential methylation (q<0.1) in relation to microorganisms. The altered genes encode for proteins that are involved in immune/inflammatory responses, specifically the NF-κB signaling pathway. These data support bacteria-dependent epigenetic patterning in the placenta and provide potential insight into mechanisms that associate the presence of microorganisms in the placenta to pregnancy and neonatal outcomes. This study lays the foundation for investigations of the placental microbiome and its role in placental function.

Further Evidence of How Unbuffered Starvation at 4°C Influences Listeria monocytogenes EGD-e, HCC23, F2365, and Scott A

The soilborne pathogen Listeria monocytogenes frequently contaminates food products and food processing environments and is able to survive desiccation, high osmotic pressures, and starvation. However, little is known about how this pathogen survives starvation at 4°C. This study provides evidence that L. monocytogenes is able to survive total nutrient starvation for 4 weeks. L. monocytogenes strains EGD-e, Scott A, F2365, and HCC23 were starved individually in sterile water. Colony counts declined over 4 weeks, with Scott A declining the most rapidly. Transmission electron microscopy images revealed degradation of starving cell membranes and altered cytosols. Starving cells were subjected to the metabolic inhibitors fluoride, arsenite, 2,4-dinitrophenol, iodoacetate, and cyanide individually. Iodoacetate, which inhibits glyceraldehyde-3-phosphate dehydrogenase, completely reduced cultivable counts below the level of detection compared with the control starving cells; 2,4-dinitrophenol, which dissipates proton motive force, almost completely reduced cultivable counts. These results suggest that L. monocytogenes strains EGD-e, Scott A, F2365, and HCC23 are actively using part of the glycolysis pathway while starving. These results suggest that starving L. monocytogenes cells retain aspects of active metabolism.

Effects of sex and HIV serostatus on spatial navigational learning and memory among cocaine users

Spatial learning and memory are critically dependent on the integrity of hippocampal systems. Functional MRI and neuropathological studies show that hippocampal circuitry is prominently affected among HIV-seropositive individuals, but potential spatial learning and memory deficits have not been studied in detail in this population. We investigated the independent and interactive effects of sex and HIV serostatus on performance of a spatial learning and memory task in a sample of 181 individuals with a history of cocaine dependence. We found that men showed faster times to completion on immediate recall trials compared with women and that delayed recall was significantly poorer among HIV-infected compared with HIV-uninfected participants. Additionally, a sex × serostatus effect was found on the total number of completed learning trials. Specifically, HIV-infected men successfully completed more learning trials compared with HIV-infected women. Results are discussed in the context of recent reports of sex and HIV serostatus effects on episodic memory performance.

Chronic early childhood exposure to arsenic is associated with a TNF-mediated proteomic signaling response

Exposure to inorganic arsenic (iAs) in drinking water is a global public health concern and is associated with a range of health outcomes, including immune dysfunction. Children are a particularly sensitive population to the effects of inorganic arsenic, yet the biological mechanisms underlying adverse health outcomes are understudied. Here we used a proteomic approach to examine the effects of iAs exposure on circulating serum protein levels in a cross-sectional children's cohort in Mexico. To identify iAs-associated proteins, levels of total urinary arsenic (U-tAs) and its metabolites were determined and serum proteins assessed for differences in expression. The results indicate an enrichment of Tumor Necrosis Factor-(TNF)-regulated immune and inflammatory response proteins that displayed decreased expression levels in relation to increasing U-tAs. Notably, when analyzed in the context of the proportions of urinary arsenic metabolites in children, the most robust response was observed in relation to the monomethylated arsenicals. This study is among the first serum proteomics assessment in children exposed to iAs.

Genetic and epigenetic mechanisms underlying arsenic-associated diabetes mellitus: a perspective of the current evidence

Chronic exposure to arsenic has been associated with the development of diabetes mellitus (DM), a disease characterized by hyperglycemia resulting from dysregulation of glucose homeostasis. This review summarizes four major mechanisms by which arsenic induces diabetes, namely inhibition of insulin-dependent glucose uptake, pancreatic β-cell damage, pancreatic β-cell dysfunction and stimulation of liver gluconeogenesis that are supported by both in vivo and in vitro studies. Additionally, the role of polymorphic variants associated with arsenic toxicity and disease susceptibility, as well as epigenetic modifications associated with arsenic exposure, are considered in the context of arsenic-associated DM. Taken together, in vitro, in vivo and human genetic/epigenetic studies support that arsenic has the potential to induce DM phenotypes and impair key pathways involved in the regulation of glucose homeostasis.

Effects of smoking and marination on the sensory characteristics of cold-cut chicken breast filets: A pilot study

This study aimed to determine individual and combined effects of smoking and marination on the sensory characteristics of boneless, skinless chicken breast meat. Four types of cooked, cold-cut chicken breast meat, i.e., marinated cooked, marinated smoked, and controls of non-marinated cooked and non-marinated smoked chicken, were evaluated for 28 sensory characteristics. Marination significantly increased saltiness, sweetness, roasted flavor, smoked flavor, and moistness of the cold-cut chicken breast meat. In addition, smoking significantly enhanced the saltiness, bitterness, roasted flavor, smoked flavor, and moistness of mass. Interestingly, a combination of smoking and marination processes resulted in a synergistic increase in the perceived moistness of mass compared to their individual treatments. In conclusion, this study demonstrates individual and combined influences of smoking and marination on the sensory characteristics of cold-cut chicken breast meat.

E-cigarette use results in suppression of immune and inflammatory-response genes in nasal epithelial cells similar to cigarette smoke

Exposure to cigarette smoke is known to result in impaired host defense responses and immune suppressive effects. However, the effects of new and emerging tobacco products, such as e-cigarettes, on the immune status of the respiratory epithelium are largely unknown. We conducted a clinical study collecting superficial nasal scrape biopsies, nasal lavage, urine, and serum from nonsmokers, cigarette smokers, and e-cigarette users and assessed them for changes in immune gene expression profiles. Smoking status was determined based on a smoking history and a 3- to 4-wk smoking diary and confirmed using serum cotinine and urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) levels. Total RNA from nasal scrape biopsies was analyzed using the nCounter Human Immunology v2 Expression panel. Smoking cigarettes or vaping e-cigarettes resulted in decreased expression of immune-related genes. All genes with decreased expression in cigarette smokers (n = 53) were also decreased in e-cigarette smokers. Additionally, vaping e-cigarettes was associated with suppression of a large number of unique genes (n = 305). Furthermore, the e-cigarette users showed a greater suppression of genes common with those changed in cigarette smokers. This was particularly apparent for suppressed expression of transcription factors, such as EGR1, which was functionally associated with decreased expression of 5 target genes in cigarette smokers and 18 target genes in e-cigarette users. Taken together, these data indicate that vaping e-cigarettes is associated with decreased expression of a large number of immune-related genes, which are consistent with immune suppression at the level of the nasal mucosa.

A cross-study analysis of prenatal exposures to environmental contaminants and the epigenome: support for stress-responsive transcription factor occupancy as a mediator of gene-specific CpG methylation patterning

A biological mechanism by which exposure to environmental contaminants results in gene-specific CpG methylation patterning is currently unknown. We hypothesize that gene-specific CpG methylation is related to environmentally perturbed transcription factor occupancy. To test this hypothesis, a database of 396 genes with altered CpG methylation either in cord blood leukocytes or placental tissue was compiled from 14 studies representing assessments of six environmental contaminants. Subsequently, an in silico approach was used to identify transcription factor binding sites enriched among the genes with altered CpG methylation in relationship to the suite of environmental contaminants. For each study, the sequences of the promoter regions (representing -1000 to +500 bp from the transcription start site) of all genes with altered CpG methylation were analyzed for enrichment of transcription factor binding sites. Binding sites for a total of 56 unique transcription factors were identified to be enriched within the promoter regions of the genes. Binding sites for the Kidney-Enriched Krupple-like Factor 15, a known responder to endogenous stress, were enriched (P < 0.001-0.041) among the genes with altered CpG methylation associated for five of the six environmental contaminants. These data support the transcription factor occupancy theory as a potential mechanism underlying environmentally-induced gene-specific CpG methylation.

Apgar Score at 5 Minutes Is Associated with Mortality in Extremely Preterm Infants Even after Transfer to an All Referral NICU

OBJECTIVE

The Apgar score has been shown to have utility in predicting mortality in the extremely preterm infant in delivery hospital populations, where most mortality occurs within 12 hours of birth. We tested the hypothesis that the 5 minute Apgar score would remain associated with mortality in extremely preterm infants after transfer from the delivery hospital to an all referral neonatal intensive care unit at an average age of 10 days.

STUDY DESIGN

A retrospective analysis of 454 infants born at < 27 weeks gestation.

RESULTS

The median Apgar score was 3 at 1 minute (interquartile range [IQR] 2-6) and 6 at 5 minutes (IQR 4-7). The Apgar score increased from 1 to 5 minutes by 2.0 ± 1.7 (p < 0.001). In logistic regression modeling, an Apgar score of < 5 at 5 minutes was associated with an increased mortality (odds ratio 1.76 [95% confidence interval 1.06-2.94], p < 0.05), but not morbidities.

CONCLUSION

Infants born at < 27 weeks gestation admitted to an all referral children's hospital at a mean age of 10 days with a 5 minute Apgar < 5 are at an increased risk of mortality. Our findings continue to support the importance of the Apgar score given at delivery even in the extremely preterm infant referred to a nondelivery children's hospital.

Sweetgum: An ancient source of beneficial compounds with modern benefits

Sweetgum trees are large, deciduous trees found in Asia and North America. Sweetgum trees are important resources for medicinal and other beneficial compounds. Many of the medicinal properties of sweetgum are derived from the resinous sap that exudes when the outer bark of the tree has been damaged. The sap, known as storax, has been used for centuries to treat common ailments such as skin problems, coughs, and ulcers. More recently, storax has proven to be a strong antimicrobial agent even against multidrug resistant bacteria such as methicillin-resistant Staphylococcus aureus. In addition to the sap, the leaves, bark, and seeds of sweetgum also possess beneficial compounds such as shikimic acid, a precursor to the production of oseltamivir phosphate, the active ingredient in Tamiflu®–an antiviral drug effective against several influenza viruses. Other extracts derived from sweetgum trees have shown potential as antioxidants, anti-inflammatory agents, and chemopreventive agents. The compounds found in the extracts derived from sweetgum sap suppress hypertension in mice. Extracts from sweetgum seeds have anticonvulsant effects, which may make them suitable in the treatment of epilepsy. In addition to the potential medicinal uses of sweetgum extracts, the extracts of the sap possess antifungal activity against various phytopathogenic fungi and have been effective treatments for reducing nematodes and the yellow mosquito, Aedes aegypti, populations thus highlighting the potential of these extracts as environment-friendly pesticides and antifungal agents. The list of value-added products derived from sweetgum trees can be increased by continued research of this abundantly occurring tree.

Quantitative risk analysis for potentially resistant E. coli in surface waters caused by antibiotic use in agricultural systems

Antibiotics are frequently used in agricultural systems to promote livestock health and to control bacterial contaminants. Given the upsurge of the resistant fecal indicator bacteria (FIB) in the surface waters, a novel statistical method namely, microbial risk assessment (MRA) was performed, to evaluate the probability of infection by resistant FIB on populations exposed to recreational waters. Diarrheagenic Escherichia coli, except E. coli O157:H7, were selected for their prevalence in aquatic ecosystem. A comparative study between a typical E. coli pathway and a case scenario aggravated by antibiotic use has been performed via Crystal Ball® software in an effort to analyze a set of available inputs provided by the US institutions including E. coli concentrations in US Great Lakes through using random sampling and probability distributions. Results from forecasting a possible worst-case scenario dose-response, accounted for an approximate 50% chance for 20% of the exposed human populations to be infected by recreational water in the U.S. However, in a typical scenario, there is a 50% chance of infection for only 1% of the exposed human populations. The uncertain variable, E. coli concentration accounted for approximately 92.1% in a typical scenario as the major contributing factor of the dose-response model. Resistant FIB in recreational waters that are exacerbated by a low dose of antibiotic pollutants would increase the adverse health effects in exposed human populations by 10 fold.

CCK1-receptor stimulation protects against gut mediator-induced lung damage during endotoxemia

Background/Aims

Cholecystokinin 1-receptor (CCK1-R) activation by long chain fatty acid (LCFA) absorption stimulates vago-vagal reflex pathways in the brain stem. The present study determines whether this reflex also activates the cholinergic anti-inflammatory pathway, a pathway known to modulate cytokine release during endotoxemia.

Methods

Mesenteric lymph was obtained from wild type (WT) and CCK1-R knockout (CCK1-R^−/−) mice intraperitoneally challenged with Lipopolysaccharid (LPS) (endotoxemic lymph, EL) and intestinally infused with vehicle or LCFA-enriched solution. The lymph was analyzed for TNFα, IL-6 and IL-10 concentration and administered to healthy recipient mice via jugular infusion. Alveolar wall thickness, myeloperoxidase (MPO) and TUNEL positive cells were determined in lung tissue of recipient mice.

Results

LCFA infusion in WT mice reduced TNFα concentration in EL by 49% compared to vehicle infusion, but had no effect in CCK1-R^−/− mice. EL significantly increased the alveolar wall thickness, the number of MPO-positive and TUNEL-positive cells compared to control lymph administration. LCFA infusion in WT, but not in CCK1R^−/− mice, significantly reduced these pathological effects of EL.

Conclusion

During endotoxemia enteral LCFA absorption reduces TNFα release into mesenteric lymph and attenuates histomorphologic parameters of lung dysfunction. Failure to elicit this effect in CCK1R^−/− mice demonstrates that anti-inflammatory properties of LCFAs are mediated through CCK1-Rs.

Electrostatic spraying of food-grade organic and inorganic acids and plant extracts to decontaminate Escherichia coli O157:H7 on spinach and iceberg lettuce

The prevalence of foodborne illnesses is continually on rise. In the U.S.A., Escherichia coli O157:H7 (E. coli) has been associated with several outbreaks in minimally processed foods. Spinach and lettuce pose higher food safety risks and recurring food recalls suggest the insufficiency of current disinfection strategies. We aimed at offering a natural antimicrobial alternative using organic acids (malic, tartaric, and lactic acids [MA, TA, and LA, respectively]) and grape seed extract (GSE) and a novel application method using electrostatic spraying to evenly distribute the antimicrobials onto produce. Spinach and lettuce samples were washed, sanitized with sodium hypochlorite solution (6.25 mL/L), dip inoculated in water containing E. coli (7.0 log CFU/mL) for 24 h, and rewashed with sterile water to remove nonadhered pathogens. The samples were sprayed electrostatically with MA, LA, and GSE alone and in combinations and for comparison, with phosphoric acid (PA) and pH controls with deionized water adjusted to 1.5/2.3/3.6 and stored at 4 °C. When combined with LA (3%), MA (3%) showed 2.1 to 4.0 log CFU/g reduction of E. coli between the days 1 and 14 on spinach and 1.1 to 2.5 log CFU/g reduction on lettuce. Treatment with PA (1.5%) and PA (1.5%)-GSE (2%) exhibited 1.1 to 2.1 log CFU/g inhibition of E. coli on spinach during the 14-d storage. Our findings demonstrated the efficacy of electrostatic spraying of MA, LA, and GSE on fresh produce to improve the safety and lower the public health burden linked to produce contamination.

PRACTICAL APPLICATION

Electrostatic spraying is an emerging technique that can be adopted to improve the distribution and application of antimicrobials during fresh produce sanitation. Relatively simple and quick, the process can access most/all parts of produce surface and offer protection from food pathogens. The use of malic and lactic acids with or without grape seed extract can serve as effective antimicrobials when sprayed electrostatically, lowering the risk from postcontamination issues with spinach and iceberg lettuce. This application technology can be extended to improve the commercial food safety of other produce, fruits, poultry, and meat.

Cleaning and decontamination efficacy of wiping cloths and silver dihydrogen citrate on food contact surfaces

AIMS

  To test the efficacy of four wipe cloth types (cotton bar towel, nonwoven, microfibre and blended cellulose/cotton) with either quaternary ammonia cleaning solution or silver dihydrogen citrate (SDC) in cleaning food contact surfaces.

METHODS

  Swab samples collected from untreated, cloth-treated and cloth disinfectant-treated surfaces were subjected to hygiene monitoring using adenosine triphosphate (ATP) bioluminescence and aerobic total plate counting (TPC) assays.

RESULTS

  Adenosine triphosphate measurements taken after wiping the surfaces showed poor cleaning by nonwoven cloths (2·89 RLU 100 cm(-2) ) than the microfibre (2·30 RLU 100 cm(-2) ), cotton terry bar (2·26 RLU 100 cm(-2) ) and blended cellulose/cotton cloth types (2·20 RLU 100 cm(-2) ). The cellulose/cotton cloth showed highest log reduction in ATP-B RLU values (95%) and CFU values (98·03%) when used in combination with SDC disinfectant.

CONCLUSIONS

  Cleaning effect of wiping cloths on food contact surfaces can be enhanced by dipping them in SDC disinfectant. ATP-B measurements can be used for real-time hygiene monitoring in public sector, and testing microbial contamination provides more reliable measure of cleanliness.

SIGNIFICANCE AND IMPACT OF THE STUDY

  Contaminated food contact surfaces need regular hygiene monitoring. This study could help to estimate and establish contamination thresholds for surfaces at public sector facilities and to base the effectiveness of cleaning methods.

Antimicrobial effect and mode of action of terpeneless cold-pressed Valencia orange essential oil on methicillin-resistant Staphylococcus aureus

AIMS

The objectives of this study were to evaluate the antistaphylococcal effect and elucidate the mechanism of action of orange essential oil against antibiotic-resistant Staphylococcus aureus strains.

METHODS AND RESULTS

The inhibitory effect of commercial orange essential oil (EO) against six Staph. aureus strains was tested using disc diffusion and agar dilution methods. The mechanism of EO action on MRSA was analysed by transcriptional profiling. Morphological changes of EO-treated Staph. aureus were examined using transmission electron microscopy. Results showed that 0·1% of terpeneless cold-pressed Valencia orange oil (CPV) induced the cell wall stress stimulon consistent with the inhibition of cell wall synthesis. Transmission electron microscopic observation revealed cell lysis and suggested a cell wall lysis-related mechanism of CPV.

CONCLUSIONS

CPV inhibits the growth of Staph. aureus, causes gene expression changes consistent with the inhibition of cell wall synthesis, and triggers cell lysis.

SIGNIFICANCE AND IMPACT OF THE STUDY

Multiple antibiotics resistance is becoming a serious problem in the management of Staph. aureus infections. In this study, the altered expression of cell wall-associated genes and subsequent cell lysis in MRSA caused by CPV suggest that it may be a potential antimicrobial agent to control antibiotic-resistant Staph. aureus.

A TAT-frataxin fusion protein increases lifespan and cardiac function in a conditional Friedreich's ataxia mouse model

Friedreich's ataxia (FRDA) is the most common inherited human ataxia and results from a deficiency of the mitochondrial protein, frataxin (FXN), which is encoded in the nucleus. This deficiency is associated with an iron-sulfur (Fe-S) cluster enzyme deficit leading to progressive ataxia and a frequently fatal cardiomyopathy. There is no cure. To determine whether exogenous replacement of the missing FXN protein in mitochondria would repair the defect, we used the transactivator of transcription (TAT) protein transduction domain to deliver human FXN protein to mitochondria in both cultured patient cells and a severe mouse model of FRDA. A TAT-FXN fusion protein bound iron in vitro, transduced into mitochondria of FRDA deficient fibroblasts and reduced caspase-3 activation in response to an exogenous iron-oxidant stress. Injection of TAT-FXN protein into mice with a conditional loss of FXN increased their growth velocity and mean lifespan by 53% increased their mean heart rate and cardiac output, increased activity of aconitase and reversed abnormal mitochondrial proliferation and ultrastructure in heart. These results show that a cell-penetrant peptide is capable of delivering a functional mitochondrial protein in vivo to rescue a very severe disease phenotype, and present the possibility of TAT-FXN as a protein replacement therapy.

Molecular and neuroanatomical characterization of single neurons in the mouse medullary gigantocellular reticular nucleus

Medullary gigantocellular reticular nucleus (mGi) neurons have been ascribed a variety of behaviors, many of which may fall under the concepts of either arousal or motivation. Despite this, many details of the connectivity of mGi neurons, particularly in reference to those neurons with ascending axons, remain unknown. To provide a neuroanatomical and molecular characterization of these cells, with reference to arousal and level-setting systems, large medullary reticular neurons were characterized with retrograde dye techniques and with real-time reverse transcriptase PCR (RT-PCR) analyses of single-neuron mRNA expression in the mouse. We have shown that receptors consistent with participation in generalized arousal are expressed by single mGi neurons and that receptors from different families of arousal-related neurotransmitters are rarely coexpressed. Through retrograde labeling, we have shown that neurons with ascending axons and neurons with descending axons tend to form like-with-like clusters, a finding that is consistent across age and gender. In comparing the two groups of retrogradely labeled neurons in neonatal animals, those neurons with axons that ascend to the midbrain show markers for GABAergic or coincident GABAergic and glutamatergic function; in contrast, approximately 60% of the neurons with axons that descend to the spinal cord are glutamatergic. We discuss the mGi's relationship to the voluntary and emotional motor systems and speculate that neurons in the mGi may represent a mammalian analogue to Mauthner cells, with a separation of function for neurons with ascending and descending axons.

Development of the antiviral state in response to interferon

The development of resistance in response to interferon depends on cellular RNA synthesis and probably also on cellular protein synthesis. The evidence for these requirements is reviewed, as well as the proposal that this evidence indicates the existence of a specific response of the cell to interferon, involving the induced synthesis of an antiviral protein. Direct evidence for such an interpretation has not been obtained, and alternative explanations are discussed which do not require quantitative or qualitative differences in the RNA and protein made in cells exposed to interferon. The possible role of the ribosome in the antiviral action of interferon is also discussed.

Implementation of a multidisciplinary guideline-driven approach to the care of the extremely premature infant improved hospital outcomes

AIM

To test the hypothesis that implementing guidelines for the standardized care of the extremely premature infant (<27 weeks) in the first week of life would improve patient outcomes in an all referral NICU.

METHODS

Data were collected on all infants <27 weeks gestational age and <7 days of age on admission cared for using these small baby guidelines (SBG), as well as on all age-matched infants admitted the year prior (comparison).

RESULTS

Thirty-seven patients were cared for utilizing the SBG and 40 patients were in the comparison group. There were no differences between the groups in gestational age, birthweight or age on admission. There was no difference in survival to discharge (73% SBG, 70% comparison). The mean length of stay for survivors was 112 +/- 38 days SBG and 145 +/- 76 days (p < 0.05) comparison group. Survival without BPD was greater in the SBG group (24%) than in the comparison group (9%; p < 0.05), and survival without severe IVH was greater in the SBG group (65%) than in the comparison group (38%; p < 0.01).

CONCLUSIONS

These data demonstrate that applying a unified approach to the care of the extremely premature infant in the first week of life resulted in a decrease in the length of hospitalization and improved patient outcomes.