Inferring Past Pesticide Exposures: A Matrix of Individual Active Ingredients in Home and Garden Pesticides Used in Past Decades

BACKGROUND: In retrospective studies of the health effects of home and garden pesticides, self-reported information typically forms the basis for exposure assessment. Study participants generally find it easier to remember the types of pests treated than the specific pesticides used. However, if the goal of the study is to assess disease risk from specific chemicals, the investigator must be able to link the pest type treated with specific chemicals or products. OBJECTIVES: Our goal was to develop a “pesticide–exposure matrix” that would list active ingredients on the market for treating different types of pests in past years, and provide an estimate of the probability that each active ingredient was used. METHODS: We used several different methods for deriving the active ingredient lists and estimating the probabilities. These methods are described in this article, along with a sample calculation and data sources for each. RESULTS: The pesticide–exposure matrix lists active ingredients and their probabilities of use for 96 distinct scenarios defined by year (1976, 1980, 1990, 2000), applicator type (consumer, professional), and pest type (12 categories). Calculations and data sources for all 96 scenarios are provided online. CONCLUSIONS: Although we are confident that the active ingredient lists are reasonably accurate for most scenarios, we acknowledge possible sources of error in the probability estimates. Despite these limitations, the pesticide–exposure matrix should provide valuable information to researchers interested in the chronic health effects of residential pesticide exposure

The Arabidopsis ATK1 gene is required for spindle morphogenesis in male meiosis

The spindle plays a central role in chromosome segregation during mitosis and meiosis. In particular, various kinesins are thought to play crucial roles in spindle structure and function in both mitosis and meiosis of fungi and animals. A group of putative kinesins has been previously identified in Arabidopsis, called ATK1-ATK4 (previously known as KATA-KATD), but their in vivo functions have not been tested with genetic studies. We report here the isolation and characterization of a mutant, atk1-1, which has a defective ATK1 gene. The atk1-1 mutant was identified in a collection of Ds transposon insertion lines by its reduced fertility. Reciprocal crosses between the atk1-1 mutant and wild type showed that only male fertility was reduced, not female fertility. Molecular analyses, including revertant studies, indicated that the Ds insertion in the ATK1 gene was responsible for the fertility defect. Light microscopy revealed that, in the atk1-1 mutant, male meiosis was defective, producing an abnormal number of microspores of variable sizes. Further cytological studies indicated that meiotic chromosome segregation and spindle organization were both abnormal in the mutant. Specifically, the atk1-1 mutant male meiotic cells had spindles that were broad, unfocused and multi-axial at the poles at metaphase I, unlike the typical fusiform bipolar spindle found in the wild-type metaphase I cells. Therefore, the ATK1 gene plays a crucial role in spindle morphogenesis in male Arabidopsis meiosis

Influence of subretinal fluid in advanced stage retinopathy of prematurity on proangiogenic response and cell proliferation

Purpose The clinical phenotype of advanced stage retinopathy of prematurity (ROP, stages 4 and 5) cannot be replicated in an animal model. To dissect the molecular events that can lead up to advanced ROP, we examined subretinal fluid (SRF) and surgically dissected retrolental membranes from patients with advanced ROP to evaluate its influences on cell proliferation, angiogenic properties, and macrophage polarity. Methods: We compared our findings to SRF collected from patients with uncomplicated rhegmatogenous retinal detachment (RD) without proliferative vitreoretinopathy and surgically dissected epiretinal membrane from eyes with macular pucker. All subretinal fluid samples were equalized for protein. The angiogenic potential of SRF from ROP eyes was measured using a combination of capillary cord formation in a fibrin clot assay, and its proliferative effect was tested with a DNA synthesis of human retinal microvascular endothelial cells. Findings were compared with SRF collected from participants with uncomplicated rhegmatogenous RD without proliferative vitreoretinopathy. The ability of SRF to induce nitric oxide production was measured in vitro using murine J774A.1 macrophages. Cytokine profiles of SRF from ROP and RD eyes were measured using a multienzyme-linked immunosorbent assay (ELISA). Fluorescent immunohistochemistry of retrolental membranes from ROP was performed to detect the presence of leukocytes and the composition of tissue macrophages using markers for M1 and M2 differentiation. Results: The cytokine composition in SRF revealed that in ROP, not only were several proangiogenic factors were preferentially elevated but also the profile of proinflammatory factors was also increased compared to the RD eyes. SRF from ROP eyes supported cell proliferation and endothelial cord formation while SRF from RD eyes had inhibitory effects. SRF from eyes with ROP but not RD robustly induced nitric oxide production in macrophages. Furthermore, fluorescent immunostaining revealed a preponderance of M1 over M2 macrophages in retrolental fibrous membranes from ROP eyes. The cytokine profile and biologic properties of SRF in ROP promote a proangiogenic environment, which supports the maintenance and proliferation of fibrous membranes associated with advanced stages of ROP. In contrast, SRF from RD eyes exhibits a suppressive environment for endothelial cell proliferation and angiogenesis. Conclusions: Our investigation demonstrates that the microenvironment in advanced ROP eyes is proangiogenic and proinflammatory. These findings suggest that management of advanced ROP should not be limited to the surgical removal of the fibrovascular membranes and antiangiogenic therapy but also directed to anti-inflammatory therapy and to promote M2 activation over M1 activity

Improving the Accessibility and Efficacy of the UVMMC CHNA to Populations Experiencing Homelessness

Under provisions in the Affordable Care Act, tax-exempt hospitals are required to conduct a triennial Community Health Needs Assessment (CHNA) to identify and prioritize the health needs of the community served. UVMMC is preparing to conduct the 2022 CHNA and is exploring best outreach approaches to marginalized or historically underrepresented populations within Chittenden and Grand Isle counties. Research Question: What actions can be taken to effectively understand the diversity of needs in the homeless population of Chittenden County? Hypothesis: The current CHNA incompletely captures how health barriers are disproportionately experienced by the homeless population in Chittenden County. Goals: Identify best practices and tailor outreach methods to better assess the needs of the homeless population.https://scholarworks.uvm.edu/comphp_gallery/1319/thumbnail.jp

Tibet, the Himalaya, Asian monsoons and biodiversity - In what ways are they related?

Prevailing dogma asserts that the uplift of Tibet, the onset of the Asian monsoon system and high biodiversity in southern Asia are linked, and that all occurred after 23 million years ago in the Neogene. Here, spanning the last 60 million years of Earth history, the geological, climatological and palaeontological evidence for this linkage is reviewed. The principal conclusions are that: 1) A proto-Tibetan highland existed well before the Neogene and that an Andean type topography with surface elevations of at least 4.5 km existed at the start of the Eocene, before final closure of the Tethys Ocean that separated India from Eurasia. 2) The Himalaya were formed not at the start of the India-Eurasia collision, but after much of Tibet had achieved its present elevation. The Himalaya built against a pre-existing proto-Tibetan highland and only projected above the average height of the plateau after approximately 15 Ma. 3) Monsoon climates have existed across southern Asia for the whole of the Cenozoic, and probably for a lot longer, but that they were of the kind generated by seasonal migrations of the Inter-tropical Convergence Zone. 4) The projection of the High Himalaya above the Tibetan Plateau at about 15 Ma coincides with the development of the modern South Asia Monsoon. 5) The East Asia monsoon became established in its present form about the same time as a consequence of topographic changes in northern Tibet and elsewhere in Asia, the loss of moisture sources in the Asian interior and the development of a strong winter Siberian high as global temperatures declined. 6) New radiometric dates of palaeontological finds point to southern Asia's high biodiversity originating in the Paleogene, not the Neogene

Stripes in cuprate superconductors: Excitations and dynamic dichotomy

We present a short account of the present experimental situation of stripes in cuprates followed by a review of our present understanding of their ground state and excited state properties. Collective modes, the dynamical structure factor, and the optical conductivity of stripes are computed using the time-dependent Gutzwiller approximation applied to realistic one band and three band Hubbard models, and are found to be in excellent agreement with experiment. On the other hand, experiments like angle-resolved photoemission and scanning tunneling microscopy show the coexistence of stripes at high energies with Fermi liquid quasiparticles at low energies. We show that a phenomenological model going beyond mean-field can reconcile this dynamic dichotomy.Comment: 20 pages, 14 figures. Review paper for a Special Issue of Physica C on "Stripes and Electronic Liquid Crystals in Strongly Correlated Systems

On the Nature and Genesis of EUV Waves: A Synthesis of Observations from SOHO, STEREO, SDO, and Hinode

A major, albeit serendipitous, discovery of the SOlar and Heliospheric Observatory mission was the observation by the Extreme Ultraviolet Telescope (EIT) of large-scale Extreme Ultraviolet (EUV) intensity fronts propagating over a significant fraction of the Sun's surface. These so-called EIT or EUV waves are associated with eruptive phenomena and have been studied intensely. However, their wave nature has been challenged by non-wave (or pseudo-wave) interpretations and the subject remains under debate. A string of recent solar missions has provided a wealth of detailed EUV observations of these waves bringing us closer to resolving their nature. With this review, we gather the current state-of-art knowledge in the field and synthesize it into a picture of an EUV wave driven by the lateral expansion of the CME. This picture can account for both wave and pseudo-wave interpretations of the observations, thus resolving the controversy over the nature of EUV waves to a large degree but not completely. We close with a discussion of several remaining open questions in the field of EUV waves research.Comment: Solar Physics, Special Issue "The Sun in 360",2012, accepted for publicatio

Prediction of post-operative necrosis after mastectomy: A pilot study utilizing optical diffusion imaging spectroscopy

<p>Abstract</p> <p>Introduction</p> <p>Flap necrosis and epidermolysis occurs in 18-30% of all mastectomies. Complications may be prevented by intra-operative detection of ischemia. Currently, no technique enables quantitative valuation of mastectomy skin perfusion. Optical Diffusion Imaging Spectroscopy (ViOptix T.Ox Tissue Oximeter) measures the ratio of oxyhemoglobin to deoxyhemoglobin over a 1 × 1 cm area to obtain a non-invasive measurement of perfusion (StO₂).</p> <p>Methods</p> <p>This study evaluates the ability of ViOptix T.Ox Tissue Oximeter to predict mastectomy flap necrosis. StO₂measurements were taken at five points before and at completion of dissection in 10 patients. Data collected included: demographics, tumor size, flap length/thickness, co-morbidities, procedure length, and wound complications.</p> <p>Results</p> <p>One patient experienced mastectomy skin flap necrosis. Five patients underwent immediate reconstruction, including the patient with necrosis. Statistically significant factors contributing to necrosis included reduction in medial flap StO₂(p = 0.0189), reduction in inferior flap StO₂(p = 0.003), and flap length (p = 0.009).</p> <p>Conclusion</p> <p>StO₂reductions may be utilized to identify impaired perfusion in mastectomy skin flaps.</p

Altered Neurocircuitry in the Dopamine Transporter Knockout Mouse Brain

The plasma membrane transporters for the monoamine neurotransmitters dopamine, serotonin, and norepinephrine modulate the dynamics of these monoamine neurotransmitters. Thus, activity of these transporters has significant consequences for monoamine activity throughout the brain and for a number of neurological and psychiatric disorders. Gene knockout (KO) mice that reduce or eliminate expression of each of these monoamine transporters have provided a wealth of new information about the function of these proteins at molecular, physiological and behavioral levels. In the present work we use the unique properties of magnetic resonance imaging (MRI) to probe the effects of altered dopaminergic dynamics on meso-scale neuronal circuitry and overall brain morphology, since changes at these levels of organization might help to account for some of the extensive pharmacological and behavioral differences observed in dopamine transporter (DAT) KO mice. Despite the smaller size of these animals, voxel-wise statistical comparison of high resolution structural MR images indicated little morphological change as a consequence of DAT KO. Likewise, proton magnetic resonance spectra recorded in the striatum indicated no significant changes in detectable metabolite concentrations between DAT KO and wild-type (WT) mice. In contrast, alterations in the circuitry from the prefrontal cortex to the mesocortical limbic system, an important brain component intimately tied to function of mesolimbic/mesocortical dopamine reward pathways, were revealed by manganese-enhanced MRI (MEMRI). Analysis of co-registered MEMRI images taken over the 26 hours after introduction of Mn^(2+) into the prefrontal cortex indicated that DAT KO mice have a truncated Mn^(2+) distribution within this circuitry with little accumulation beyond the thalamus or contralateral to the injection site. By contrast, WT littermates exhibit Mn^(2+) transport into more posterior midbrain nuclei and contralateral mesolimbic structures at 26 hr post-injection. Thus, DAT KO mice appear, at this level of anatomic resolution, to have preserved cortico-striatal-thalamic connectivity but diminished robustness of reward-modulating circuitry distal to the thalamus. This is in contradistinction to the state of this circuitry in serotonin transporter KO mice where we observed more robust connectivity in more posterior brain regions using methods identical to those employed here

Mechanisms of Adaptation from a Multiple to a Single Step Recovery Strategy following Repeated Exposure to Forward Loss of Balance in Older Adults

When released from an initial, static, forward lean angle and instructed to recover with a single step, some older adults are able to meet the task requirements, whereas others either stumble or fall. The purpose of the present study was to use the concept of margin of stability (MoS) to investigate balance recovery responses in the anterior-posterior direction exhibited by older single steppers, multiple steppers and those that are able to adapt from multiple to single steps following exposure to repeated forward loss of balance. One hundred and fifty-one healthy, community dwelling, older adults, aged 65–80 years, participated in the study. Participants performed four trials of the balance recovery task from each of three initial lean angles. Balance recovery responses in the anterior-posterior direction were quantified at three events; cable release (CR), toe-off (TO) and foot contact (FC), for trials performed at the intermediate lean angle. MoS was computed as the anterior-posterior distance between the forward boundary of the Base of Support (BoS) and the vertical projection of the velocity adjusted centre of mass position (XCoM). Approximately one-third of participants adapted from a multiple to a single step recovery strategy following repeated exposure to the task. MoS at FC for the single and multiple step trials in the adaptation group were intermediate between the exclusively single step group and the exclusively multiple step group, with the single step trials having a significant, 3.7 times higher MoS at FC than the multiple step trials. Consistent with differences between single and multiple steppers, adaptation from multiple to single steps was attributed to an increased BoS at FC, a reduced XCoM at FC and an increased rate of BoS displacement from TO to FC. Adaptations occurred within a single test session and suggest older adults that are close to the threshold of successful recovery can rapidly improve dynamic stability following repeated exposure to a forward loss of balance