La gaviota dominicana como bioindicador de los productos químicos ambientales en la región de Magallanes. Una comparación con otras localidades costeras en Chile

During the breeding seasons 1994/5 and 1995/6 we collected Kelp Gull (Larus dominicanus) eggs from five locations in central to south Chile to study the contamination with mercury and organochlorine compounds. The sites were Algarrobo, Concepción, Maiquillahue Bay, Doña Sebastiana Island (Chalcao channel at Chiloé) and Magdalena Island (Straits of Magellan). We found differences among the sites: Kelp Gull eggs from Chiloé and Algarrobo had the greatest concentrations of mercury (about 170 ng g-1 fresh weight). Residues of DDT were greatest in eggs from Algarrobo and Maiquillahue Bay, those of PCBs (polychlorinated biphenyls) greatest at Algarrobo and Concepción. HCB had highest levels at Concepción. Considering all organochlorines, samples from Algarrobo had the highest concentrations, those from Chiloé the lowest. In consequence we found a geographical pattern from north to south, i.e., from areas with greater to lesser human impact. In comparison with other studies, the levels of environmental chemicals found in Kelp Gulls from Chile are much lower than those known to cause adverse effects on reproductive success.Durante las estaciones reproductoras de los años 1994/5 y 1995/6 recolectamos huevos de la gaviota dominicana (Larus dominicanus) en cinco localidades ubicadas entre el centro y sur de Chile para el estudio de la contaminación por mercurio y compuestos organohalogenados. Dichas localidades fueron Algarrobo, Concepción, Bahía de Maiquillahue, Isla Doña Sebastiana (Canal de Chacao-Chiloé) e Isla Magdalena (Estrecho de Magallanes). Los huevos de la gaviota dominicana provenientes de la Isla Doña Sebastiana y Algarrobo presentaron las mayores concentraciones de mercurio (170 ng g-1 peso fresco). Los mayores niveles de residuos de DDT fueron detectados en las muestras procedentes de Algarrobo y de Bahía de Maiquillahue, los mayores niveles de residuos de PCBs (bifenilos policlorinados) en las muestras de Algarrobo y de Concepcíon. Los mayores valores de HCB se hallaron en Concepción. Considerando la suma de todos los compuestos organoclorados, los huevos provenientes de Algarrobo presentaron las mayores concentraciones y los de la Isla Doña Sebastiana las menores. En consecuencia, se encuentra un patrón de variación geográfica de norte a sur y de mayor a menor impacto. En comparación con otros estudios, los niveles de los productos químicos ambientales encontrados en los huevos de gaviota dominicana en Chile pueden considerarse muy bajos como para provocar efectos adversos sobre el éxito reproductor

A Survey of Mosquito Populations for Evidence of Lateral Gene Transfer.

Lateral gene transfer is an important evolutionary mechanism between organisms through a variety of processes. In prokaryotes it can be mediated by conjugation, transformation and transduction, and in eukaryotes, transposable elements and viruses play a key role. Additionally, complex evolutionary relationships driven by lateral gene transfer can exist in eukaryotic organisms infected with prokaryotes. One such evolutionary system is seen in mosquitoes carrying Dirofilaria immitis (the causative agent of heartworm) and WO phage-infected Wolbachia pipientis. The studies herein explored evidence of lateral gene transfer in this system of coevolution. Mosquitoes were trapped using resting boxes or light traps and identified taxonomically. Mosquito genomic DNA was used to perform polymerase chain reaction (PCR) to detect the W. pipientis surface protein (wsp) gene. PCR products from Culiseta melanura (856 bp) and A. quadrimaculatus (806 bp) were cloned, sequenced and subjected to genomic analysis. DNA sequencing data showed a 29 bp region corresponding to the upstream primer region at the beginning of the PCR product with 100% homology to the wsp gene. A downstream region of 31 bp at the end of the DNA sequence had 92% homology to the wsp gene. In addition, the 856 bp and 806 bp PCR product was comprised of unidentified DNA with 73-74% homology to Aedes egypti. A detailed analysis is difficult since the genomic DNA sequence for these mosquitoes has not yet been reported. However this data supports that these PCR products have mosquito origin. The data also evidence lateral gene transfer of wsp into these mosquito genomes. Additionally, Anopheles species may also contain W. pipientis DNA. These observations are noteworthy since, evidence of Wolbachia infection and lateral gene transfer of W. pipientis DNA in Anopheles mosquitoes has not been previously reported

Student perceptions of the school physical fitness testing program : the Fitnessgram

The purpose of this study was to determine fifth grade students\u27 perceptions of the Fitnessgram physical fitness testing program. This study examined if the Fitnessgram physical fitness testing experience promotes an understanding of the health-related fitness components and examined the relationship between individual fitness test scores and time spent participating in out-of-school physical activity. Lastly, students\u27 thoughts and feelings concerning the Fitnessgram experience were examined. The primary participant population for the study was 110 fifth grade students at Redland Elementary School, a Miami-Dade County Public School (M-DCPS). Data were collected over the course of 5 months. Multiple sources of data allowed for triangulation. Data sources included Fitnessgram test scores, questionnaires, document analysis, and in-depth interviews. Interview data were analyzed qualitatively for common broad themes, which were identified and defined. Document analysis included analyzing student fitness test scores and student questionnaire data. This information was analyzed to determine if the Fitnessgram test scores have an impact on student views about the school fitness-testing program. Data were statistically analyzed using analysis of frequency, crosstabulations (Bryman & Duncan, 1997), and Somers\u27d Correlation (Bryman & Duncan, 1997). The results of the analysis of data on student knowledge of the physical fitness components tested by each Fitnessgram test revealed students do not understand the health-related fitness components. The results of determining a relationship between individuals\u27 fitness test scores and time spent in out-of-school physical activity revealed a significant positive relationship for 2 of the 6 Fitnessgram tests. The results of examining students\u27 thoughts and feelings about each Fitnessgram test focused around 2 broad themes: (a) these children do not mind the physical fitness testing and (b) how they felt about the experience was directly related to how they thought they had performed. If the goal of physical fitness was only to get children fit, this test may be appropriate. However, the ultimate goal of physical fitness is to encourage students to live active and healthy lifestyles. Findings suggest the Fitnessgram as implemented by M-DCPS may not be the most suitable measurement instrument when assessing attitudinal changes that affect a healthy lifelong lifestyle.

Diffusion tensor imaging (DTI) and tractography of the brachial plexus: feasibility and initial experience in neoplastic conditions

Introduction: The objective of this study was to assess the feasibility and potential clinical applications of diffusion tensor imaging (DTI) and tractography in the normal and pathologic brachial plexus prospectively. Methods: Six asymptomatic volunteers and 12 patients with symptoms related to the brachial plexus underwent DTI on a 1.5T system in addition to the routine anatomic plexus imaging protocol. Maps of the apparent diffusion coefficient (ADC) and of fractional anisotropy (FA), as well as tractography of the brachial plexus were obtained. Images were evaluated by two experienced neuroradiologists in a prospective fashion. Three patients underwent surgery, and nine patients underwent conservative medical treatment. Results: Reconstructed DTI (17/18) were of good quality (one case could not be reconstructed due to artifacts). In all volunteers and in 11 patients, the roots and the trunks were clearly delineated with tractography. Mean FA and mean ADC values were as follows: 0.30 ± 0.079 and 1.70 ± 0.35mm2/s in normal fibers, 0.22 ± 0.04 and 1.49 ± 0.49mm2/s in benign neurogenic tumors, and 0.24 ± 0.08 and 1.51 ± 0.52mm2/s in malignant tumors, respectively. Although there was no statistically significant difference in FA and ADC values of normal fibers and fibers at the level of pathology, tractography revealed major differences regarding fiber architecture. In benign neurogenic tumors (n = 4), tractography revealed fiber displacement alone (n = 2) or fiber displacement and encasement by the tumor (n = 2), whereas in the malignant tumors, either fiber disruption/destruction with complete disorganization (n = 6) or fiber displacement (n = 1) were seen. In patients with fiber displacement alone, surgery confirmed the tractography findings, and excision was successful without sequelae. Conclusion: Our preliminary data suggest that DTI with tractography is feasible in a clinical routine setting. DTI may demonstrate normal tracts, tract displacement, deformation, infiltration, disruption, and disorganization of fibers due to tumors located within or along the brachial plexus, therefore, yielding additional information to the current standard anatomic imaging protocol

Discovery of a Radio-Selected z ~ 6 Quasar

We present the discovery of only the second radio-selected, z ~ 6 quasar. We identified SDSS J222843.54+011032.2 (z=5.95) by matching the optical detections of the deep Sloan Digital Sky Survey (SDSS) Stripe 82 with their radio counterparts in the Stripe82 VLA Survey. We also matched the Canadian-France-Hawaiian Telescope Legacy Survey Wide (CFHTLS Wide) with the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey but have yet to find any z ~ 6 quasars in this survey area. The discovered quasar is optically-faint, z = 22.3 and M_{1450} ~ -24.5, but radio-bright, with a flux density of f$_{1.4GHz, peak}$ = 0.31mJy and a radio-loudness of R ~ 1100 (where R = f_{5GHz}/f_{2500}). The i-z color of the discovered quasar places it outside the color selection criteria for existing optical surveys. We conclude by discussing the need for deeper wide-area radio surveys in the context of high-redshift quasars.Comment: 20 pages, 6 figures, and ApJ accepte

The Effect of a Planetary Health Diet on the Human Gut Microbiome : A Descriptive Analysis

In 2019, researchers from the EAT-Lancet Commission developed the ‘Planetary Health (PH) diet’. Specifically, they provided recommendations pertaining to healthy diets derived from sustainable food systems. Thus far, it has not been analysed how such a diet affects the human intestinal microbiome, which is important for health and disease development. Here, we present longitudinal genome-wide metagenomic sequencing and mass spectrometry data on the gut microbiome of healthy volunteers adhering to the PH diet, as opposed to vegetarian or vegan (VV) and omnivorous (OV) diets. We obtained basic epidemiological information from 41 healthy volunteers and collected stool samples at inclusion and after 2, 4, and 12 weeks. Individuals opting to follow the PH diet received detailed instructions and recipes, whereas individuals in the control groups followed their habitual dietary pattern. Whole-genome DNA was extracted from stool specimens and subjected to shotgun metagenomic sequencing (~3 GB per patient). Conventional bacterial stool cultures were performed in parallel and bacterial species were identified with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. We analysed samples from 16 PH, 16 OV, and 9 VV diet patterns. The α-diversity remained relatively stable for all dietary groups. In the PH group, we observed a constant increase from 3.79% at inclusion to 4.9% after 12 weeks in relative abundance of Bifidobacterium adolescentis. Differential PH abundance analysis highlighted a non-significant increase in possible probiotics such as Paraprevotella xylaniphila and Bacteroides clarus. The highest abundance of these bacteria was observed in the VV group. Dietary modifications are associated with rapid alterations to the human gut microbiome, and the PH diet led to a slight increase in probiotic-associated bacteria at ≥4 weeks. Additional research is required to confirm these findings

Clinical applications of diffusion tensor tractography of the spinal cord

Diffusion tensor imaging (DTI) can visualize the white matter tracts in vivo. The aim of this study was to assess the clinical utility of DTI in patients with diseases of the spinal cord. Fourteen subjects underwent magnetic resonance imaging of the spine at 1.5T. Preliminary diagnosis of the patients suggested traumatic, tumorous, ischemic or inflammatory lesions of the spinal cord. In addition to T2-weighted images, DTI was performed with the gradients in 30 orthogonal directions. Maps of the apparent diffusion coefficient and of fractional anisotropy were reconstructed. Diffusion tensor imaging showed a clear displacement and deformation of the white matter tracts at the level of the pathological lesions in the spinal cord. This capability of diffusion tensor imaging to reliably display secondary alterations to the white matter tracts caused by the primary lesion has the potential to be of great utility for treatment planning and follow-u

Characteristics of the Skin Microbiome in Selected Dermatological Conditions : A Narrative Review

The skin is the largest and outermost organ of the human body. The microbial diversity of the skin can be influenced by several variable factors such as physiological state, lifestyle, and geographical locations. Recent years have seen increased interest in research aiming at an improved understanding of the relationship between the human microbiota and several diseases. Albeit understudied, interesting correlations between the skin microbiota and several dermatological conditions have been observed. Studies have shown that a decrease or increase in the abundance of certain microbial communities can be implicated in several dermatological pathologies. This narrative review (i) examines the role of the skin microbiota in the maintenance of skin homeostasis and health, (ii) provides examples on how some common skin diseases (acne inversa, candidiasis, psoriasis) are associated with the dysbiosis of microbial communities, and (iii) describes how recent research approaches used in skin microbiome studies may lead to improved, more sensitive diagnostics and individual therapeutics in the foreseeable future