Do the Poor Pay More for Healthy Food? An Empirical Economic Analysis

Food Consumption/Nutrition/Food Safety,

Comparing the yield of Staphylococcus aureus recovery with static versus agitated broth incubation

Given the lack of standardization of methodologies for microbial recovery from built environments, we sought to compare the yield of Staphylococcus aureus with a broth enrichment method when incubated in agitated versus static conditions. Five unique strains of S. aureus at five different concentrations were cultured to compare direct plating, agitated broth enrichment, and static broth enrichment culture methods. All samples were incubated at 35° in ambient air. The lowest concentration recovered across three replicates and five strains did not differ between culture methods (Fisher’s exact test, p=0.50); notably, recovery of S. aureus was equivalent between static and agitated broth incubation. When broth enrichment was used (both static and agitated), the burden of S. aureus growth was higher (by semiquantitative assessment of 4-quadrant streaking) compared to the direct plating culture method. Optimizing strategies for microbial recovery is essential, particularly in areas of lower biomass, given the paucity of research concerning microbial communities of built environments. The results of this study, in conjunction with other experiments investigating microbiomes of built environments, can help inform protocols for standardizing culturing methods within built environments

Symptom Perceptions and Self-care Behaviors in Patients Who Self-manage Heart Failure

Background: Patients with heart failure (HF) are at heightened risk for acute exacerbation requiring hospitalization. Although timely reporting of symptoms can expedite outpatient treatment and avoid the need for hospitalization, few patients recognize and respond to symptoms until acutely ill. Objective: The purpose of this study was to explore patients’ perceptions of symptoms and self-care behaviors for symptom relief, leading up to a HF hospitalization. Methods: To examine prehospitalization symptom scenarios, semistructured interviews were conducted with 60 patients hospitalized for acute decompensated HF. Results: Thirty-seven patients (61.7%) said that they had a sense that “something just wasn’t quite right” before their symptoms began but were unable to specify further. Signs and symptoms most often recognized by the patients were related to dyspnea (85%), fatigue (53.3%), and edema (41.7%). Few patients interpreted their symptoms as being related to worsening HF and most often attributed symptoms to changes in diet (18.3%) and medications (13.3%). Twenty-six patients (43.3%) used self-care strategies to relieve symptoms before hospital admission. More than 40% of the patients had symptoms at least 2 weeks before hospitalization. Conclusions: Despite the wide dissemination of HF evidence-based guidelines, important components of symptom self-management remain suboptimal. Because most of HF self-management occurs in the postdischarge environment, research is needed that identifies how patients interpret symptoms of HF in the specific contexts in which patients self-manage their HF. These findings suggest the need for interventions that will help patients expeditiously recognize, accurately interpret, and use appropriate and safe self-care strategies for symptoms

Evaluation of environmental sampling methods for detection of Staphylococcus aureus on fomites

We evaluated a variety of methods to recover S. aureus from inanimate surfaces. Two contact agar plates and three swab sampling methods were tested on porous and non-porous surfaces and bar soap. The cost and ease of use of each method was also evaluated. S. aureus was recovered using all methods on both porous and non-porous surfaces. S. aureus could not be detected on three of four brands of soap

Leucine and arginine regulate trophoblast motility through mTOR-dependent and independent pathways in the preimplantation mouse embryo

AbstractUterine implantation is a critical element of mammalian reproduction and is a tightly and highly coordinated event. An intricate and reciprocal uterine-embryo dialog exists to synchronize uterine receptivity with the concomitant activation of the blastocyst, maximizing implantation success. While a number of pathways involved in regulating uterine receptivity have been identified in the mouse, less is understood about blastocyst activation, the process by which the trophectoderm (TE) receives extrinsic cues that initiate new characteristics essential for implantation. Amino acids (AA) have been found to regulate blastocyst activation and TE motility in vitro. In particular, we find that arginine and leucine alone are necessary and sufficient to induce TE motility. Both arginine and leucine act individually and additively to propagate signals that are dependent on the activity of the mammalian target of rapamycin complex 1 (mTORC1). The activities of the well-established downstream targets of mTORC1, p70S6K and 4EBP, do not correlate with trophoblast motility, suggesting that an independent-rapamycin-sensitive pathway operates to induce trophoblast motility, or that other, parallel amino acid-dependent pathways are also involved. We find that endogenous uterine factors act to induce mTORC1 activation and trophoblast motility at a specific time during pregnancy, and that this uterine signal is later than the previously defined signal that induces the attachment reaction. In vivo matured blastocysts exhibit competence to respond to an 8-hour AA stimulus by activating mTOR and subsequently undergoing trophoblast outgrowth by the morning of day 4.5 of pregnancy, but not on day 3.5. By the late afternoon of day 4.5, the embryos no longer require any exposure to AA to undergo trophoblast outgrowth in vitro, demonstrating the existence and timing of an equivalent in vivo signal. These results suggest that there are two separate uterine signals regulating implantation, one that primes the embryo for the attachment reaction and another that activates mTOR and initiates invasive behavior

Pattern Recognition for Mass-Spectrometry-Based Proteomics

Multiomic analysis comprises genomics, proteomics, and metabolomics leads to meaningful insights but necessitates sifting through voluminous amounts of complex data. Proteomics in particular focuses on the end product of gene expression – i.e., proteins. The mass spectrometric approach has proven to be a workhorse for the qualitative and quantitative study of protein interactions as well as post-translational modifications (PTMs). A key component of mass spectrometry (MS) is spectral data analysis, which is complex and has many challenges as it involves identifying patterns across a multitude of spectra in combination with the meta-data related to the origin of the spectrum. Artificial Intelligence (AI) along with Machine Learning (ML), and Deep Learning (DL) algorithms have gained more attention lately for analyzing the complex spectral data to identify patterns and to create networks of value for biomarker discovery. In this chapter, we discuss the nature of MS proteomic data, the relevant AI methods, and demonstrate their applicability. We also show that AI can successfully identify biomarkers and aid in the diagnosis, prognosis, and treatment of specific diseases

A test for common genetic and environmental vulnerability to depression and diabetes

Molecular genetic research has provided some evidence for the association between depression and metabolic disorders. We sought to determine if molecular findings are reflected in twin analyses testing if common genetic and environmental risk factors contribute to the co-occurrence of diabetes and depression. Data to derive depression and diabetes were collected from 1,237 male-male twins who participated in the 2005 Vietnam Era Twin Study of Aging (VETSA). The 1,237 twins were comprised of 347 MZ pairs, 3 MZ singletons, 267 DZ pairs and 6 unpaired twins. Depression was defined as a score below 46 on the Short Form-36 mental component summary score. Diabetes was defined by self report, use of anti-diabetic medications and insulin. Twin models were fit to estimate the correlation of genetic and environmental contributions to depression and diabetes. Consistent with other studies these data support the association between depression and diabetes (OR = 1.7; 95%CI: 1.1–2.7). Genetic vulnerability accounted for 50% (95%CI: 32%–65%) of the variance in risk for depression and 69% (95%CI: 52%–81%) of the variance in risk for diabetes. The genetic correlation between depression and diabetes was r = 0.19 (95%CI: 0–0.46) and the non-shared environmental correlation was r = 0.09 (95% CI: 0–0.45). Overall there is little evidence that common genetic and environmental factors account for the co-occurrence of depression and diabetes in middle aged men. Further research in female twins and larger cohorts is warranted

Antimicrobial susceptibility profiles of Staphylococcus aureus isolates recovered from humans, environmental surfaces, and companion animals in households of children with community-onset methicillin-resistant S. aureus infections

Our objective was to determine the antibiotic susceptibility profiles of Staphylococcus aureus isolates recovered from 110 households of children with community-onset methicillin-resistant S. aureus (MRSA) infections. Cultures were obtained from household members, household objects, and dogs and cats, yielding 1,633 S. aureus isolates. The S. aureus isolates were heterogeneous, although more than half were methicillin resistant. The highest proportion of MRSA was found in bathrooms. The majority of isolates were susceptible to antibiotics prescribed in outpatient settings

Longitudinal dynamics of skin bacterial communities in the context of Staphylococcus aureus decolonization

Decolonization with topical antimicrobials is frequently prescribed in health care and community settings to prevent Staphylococcus aureus infection. However, effects on commensal skin microbial communities remains largely unexplored. Within a household affected by recurrent methicillin-resistant S. aureus skin and soft tissue infections (SSTI), skin swabs were collected from the anterior nares, axillae, and inguinal folds of 14 participants at 1- to 3-month intervals over 24 months. Four household members experienced SSTI during the first 12-months (observational period) and were prescribed a 5-day decolonization regimen with intranasal mupirocin and bleach water baths at the 12-month study visit. We sequenced the 16S rRNA gene V1-V2 region and compared bacterial community characteristics between the pre- and post-intervention periods and between younger and older subjects. The median Shannon diversity index was stable during the 12-month observational period at all three body sites. Bacterial community characteristics (diversity, stability, and taxonomic composition) varied with age. Among all household members, not exclusively among the four performing decolonization, diversity was unstable throughout the year post-intervention. In the month after decolonization, bacterial communities were changed. Although communities largely returned to their baseline states, relative abundance of some taxa remained changed throughout the year following decolonization (e.g., more abundan