1,916 research outputs found

    Vinalhaven Lobstermen’s Co-Operative, 1938

    Get PDF
    The author describes his experience helping the lobstermen of Vinalhaven to form cooperative buying and marketing club, in 1938

    Postoperative pulmonary edema in young, athletic adults

    Full text link
    Pulmonary edema secondary to postextubation laryn gospasm is a potentially life-threatening problem, de manding early diagnosis and prompt treatment. We believe that this problem has been grossly underesti mated in its incidence, as only seven adults have been reported in the English literature, whereas seven adults have been observed at our institution in only a 24 month period. All were young, healthy, athletic adult males (average weight, 218 pounds) who underwent relatively minor, uncomplicated surgical procedures under gen eral anesthesia. Five of these patients were collegiate and/or profes sional athletes and had meticulous medical records detailing their clinical course. Clinical laryngospasm was noted immediately following extubation and anesthesia by mask with subsequent pulmonary edema. The di agnoses were confirmed by clinical examination, arterial blood gas determinations or pulse oximetry, and chest roentgenogram. Four adults required reintubation. Six of the seven adults demonstrated very rapid resolution of the pulmonary edema with prompt diagnosis and institution of a therapeutic regimen including oxygen, diuretics, reintubation, and/or positive pressure venti lation. In one patient, the problem was not immediately recognized, and progressed to florid pulmonary edema requiring emergent intubation 14 hours later in the emergency room, and 3 days of mechanical ventilation. The etiology of pulmonary edema following upper airway obstruction represents an interplay between several factors: cardiogenic and neurogenic mecha nisms, as well as hypoxia contribute. In this group, excessive negative intrathoracic pressure generated by forced inspiration against a closed glottis is the most likely, consistent, and logical explanation. This study suggests that young, healthy, athletic males may be at increased risk for this complication. We believe that their enhanced ability to generate ex cessive negative intrathoracic pressures is, at least in part, responsible. A heightened awareness of the prob lem in this at-risk group should invoke special consid erations, including choice of anesthesia, precautions on extubation, prolonged monitoring in the recovery phase if laryngospasm is observed or suspected, and rapid therapeutic intervention.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66519/2/10.1177_036354659101900407.pd

    The Landscape of Human Proteins Interacting with Viruses and Other Pathogens

    Get PDF
    Infectious diseases result in millions of deaths each year. Mechanisms of infection have been studied in detail for many pathogens. However, many questions are relatively unexplored. What are the properties of human proteins that interact with pathogens? Do pathogens interact with certain functional classes of human proteins? Which infection mechanisms and pathways are commonly triggered by multiple pathogens? In this paper, to our knowledge, we provide the first study of the landscape of human proteins interacting with pathogens. We integrate human–pathogen protein–protein interactions (PPIs) for 190 pathogen strains from seven public databases. Nearly all of the 10,477 human-pathogen PPIs are for viral systems (98.3%), with the majority belonging to the human–HIV system (77.9%). We find that both viral and bacterial pathogens tend to interact with hubs (proteins with many interacting partners) and bottlenecks (proteins that are central to many paths in the network) in the human PPI network. We construct separate sets of human proteins interacting with bacterial pathogens, viral pathogens, and those interacting with multiple bacteria and with multiple viruses. Gene Ontology functions enriched in these sets reveal a number of processes, such as cell cycle regulation, nuclear transport, and immune response that participate in interactions with different pathogens. Our results provide the first global view of strategies used by pathogens to subvert human cellular processes and infect human cells. Supplementary data accompanying this paper is available at http://staff.vbi.vt.edu/dyermd/publications/dyer2008a.html

    Evolutionary History and Attenuation of Myxoma Virus on Two Continents

    Get PDF
    The attenuation of myxoma virus (MYXV) following its introduction as a biological control into the European rabbit populations of Australia and Europe is the canonical study of the evolution of virulence. However, the evolutionary genetics of this profound change in host-pathogen relationship is unknown. We describe the genome-scale evolution of MYXV covering a range of virulence grades sampled over 49 years from the parallel Australian and European epidemics, including the high-virulence progenitor strains released in the early 1950s. MYXV evolved rapidly over the sampling period, exhibiting one of the highest nucleotide substitution rates ever reported for a double-stranded DNA virus, and indicative of a relatively high mutation rate and/or a continually changing selective environment. Our comparative sequence data reveal that changes in virulence involved multiple genes, likely losses of gene function due to insertion-deletion events, and no mutations common to specific virulence grades. Hence, despite the similarity in selection pressures there are multiple genetic routes to attain either highly virulent or attenuated phenotypes in MYXV, resulting in convergence for phenotype but not genotype. © 2012 Kerr et al

    Avian oncogenesis induced by lymphoproliferative disease virus: a neglected or emerging retroviral pathogen?

    Get PDF
    Lymphoproliferative disease virus (LPDV) is an exogenous oncogenic retrovirus that induces lymphoid tumors in some galliform species of birds. Historically, outbreaks of LPDV have been reported from Europe and Israel. Although the virus has previously never been detected in North America, herein we describe the widespread distribution, genetic diversity, pathogenesis, and evolution of LPDV in the United States. Characterization of the provirus genome of the index LPDV case from North America demonstrated an 88% nucleotide identity to the Israeli prototype strain. Although phylogenetic analysis indicated that the majority of viruses fell into a single North American lineage, a small subset of viruses from South Carolina were most closely related to the Israeli prototype. These results suggest that LPDV was transferred between continents to initiate outbreaks of disease. However, the direction (New World to Old World or vice versa), mechanism, and time frame of the transcontinental spread currently remain unknown

    Selection for Robustness in Mutagenized RNA Viruses

    Get PDF
    Mutational robustness is defined as the constancy of a phenotype in the face of deleterious mutations. Whether robustness can be directly favored by natural selection remains controversial. Theory and in silico experiments predict that, at high mutation rates, slow-replicating genotypes can potentially outcompete faster counterparts if they benefit from a higher robustness. Here, we experimentally validate this hypothesis, dubbed the “survival of the flattest,” using two populations of the vesicular stomatitis RNA virus. Characterization of fitness distributions and genetic variability indicated that one population showed a higher replication rate, whereas the other was more robust to mutation. The faster replicator outgrew its robust counterpart in standard competition assays, but the outcome was reversed in the presence of chemical mutagens. These results show that selection can directly favor mutational robustness and reveal a novel viral resistance mechanism against treatment by lethal mutagenesis

    Evolutionary Conservation of the PA-X Open Reading Frame in Segment 3 of Influenza A Virus

    Get PDF
    PA-X is a fusion protein of influenza A virus encoded in part from a +1 frameshifted X open reading frame (X-ORF) in segment 3. We show that the X-ORFs of diverse influenza A viruses can be divided into two groups that differ in selection pressure and likely function, reflected in the presence of an internal stop codon and a change in synonymous diversity. Notably, truncated forms of PA-X evolved convergently in swine and dogs, suggesting a strong species-specific effect

    Influence of the Fermi Surface Morphology on the Magnetic Field-Driven Vortex Lattice Structure Transitions in YBa2_{2}Cu3_{3}O7δ:δ=_{7-\delta}:\delta=0, 0.15

    Full text link
    We report small-angle neutron scattering measurements of the vortex lattice (VL) structure in single crystals of the lightly underdoped cuprate superconductor YBa2Cu3O6.85. At 2 K, and for fields of up to 16 T applied parallel to the crystal c-axis, we observe a sequence of field-driven and first-order transitions between different VL structures. By rotating the field away from the c-axis, we observe each structure transition to shift to either higher or lower field dependent on whether the field is rotated towards the [100] or [010] direction. We use this latter observation to argue that the Fermi surface morphology must play a key role in the mechanisms that drive the VL structure transitions. Furthermore, we show this interpretation is compatible with analogous results obtained previously on lightly overdoped YBa2Cu3O7. In that material, it has long-been suggested that the high field VL structure transition is driven by the nodal gap anisotropy. In contrast, the results and discussion presented here bring into question the role, if any, of a nodal gap anisotropy on the VL structure transitions in both YBa2Cu3O6.85 and YBa2Cu3O7

    Demographic Histories of ERV-K in Humans, Chimpanzees and Rhesus Monkeys

    Get PDF
    We detected 19 complete endogenous retroviruses of the K family in the genome of rhesus monkey (Macaca mulatta; RhERV-K) and 12 full length elements in the genome of the common chimpanzee (Pan troglodytes; CERV-K). These sequences were compared with 55 human HERV-K and 20 CERV-K reported previously, producing a total data set of 106 full-length ERV-K genomes. Overall, 61% of the human elements compared to 21% of the chimpanzee and 47% of rhesus elements had estimated integration times less than 4.5 million years before present (MYBP), with an average integration times of 7.8 MYBP, 13.4 MYBP and 10.3 MYBP for HERV-K, CERV-K and RhERV-K, respectively. By excluding those ERV-K sequences generated by chromosomal duplication, we used 63 of the 106 elements to compare the population dynamics of ERV-K among species. This analysis indicated that both HERV-K and RhERV-K had similar demographic histories, including markedly smaller effective population sizes, compared to CERV-K. We propose that these differing ERV-K dynamics reflect underlying differences in the evolutionary ecology of the host species, such that host ecology and demography represent important determinants of ERV-K dynamics

    The use of natural resources to improve household income, health, and nutrition within the forests of Kianjavato, Madagascar

    Get PDF
    Understanding natural resource extraction in Madagascar is key to developing wider conservation and management strategies that ensure the continued delivery of essential ecosystem services, and the development of health and economic strategies to meet the demands of a growing human population. In the Kianjavato lowland rainforest of southeastern Madagascar, 78% of lemur species, 83% of native carnivoran species, and 67% of frugivorous bat species are threatened with extinction. All three of these groups of mammals are commonly hunted for food in other regions of Madagascar, yet we know little about current levels of hunting or whether the use of forest resources significantly affects human welfare in this region. We used health assessments of 1267 Kianjavato residents and semi-structured interviews of members of 336 households in 17 communities in Kianjavato to investigate human-environmental interactions. We found high prevalence of child and teenage malnutrition. More than half of the population under 20 years old was stunted, more than half was underweight, and more than one fifth was wasted. Further, one in six residents were anemic. We found that Kianjavato’s forests provided essential ecosystem services for its rural communities. As Kianjavato’s forests are altered to meet the needs of a growing human population, these direct-use ecosystem services (such as the use of wild animals for food or plants for medicine) are unable to similarly expand to meet the basic needs of the families living in these forests. A worrying proportion of the Kianjavato population depends on forests to meet their healthcare, nutritional, and economic needs, yet they may be failing to do so. All surveyed households (100%) depended on forests to meet their healthcare needs and 40% of the regional economy involved the extraction of finite forest resources (i.e., precious stones). Most households consumed very little wildlife (two animals per household per year) and the great majority (83%) of the forest animals they ate were not threatened with extinction. Forty percent of wildlife were caught illegally. Although hunting is likely not imperiling local wildlife at present, 16% of the Kianjavato population hunts wildlife and 20% are malnourished. The ecosystem services of Kianjavato’s forests may currently be insufficient to meet the needs of residents. Therefore, targeted efforts to increase local access to the healthcare system and to improve household nutrition and economy by improving the production and stability of local agricultural products may increase the long-term sustainability of both wildlife hunting, household incomes, and regional food security. Efforts such as these that can expand with the growing population to meet future needs may help secure the sustainable use of essential ecosystem services for the long term, improving the health of local people and maintaining the integrity of the forests in which they live. RésuméComprendre l'utilisation des ressources naturelles à Madagascar est essentiel pour développer des stratégies de conservation et de gestion plus larges qui permettent à la fois de fournir des services écosystémiques et de développer des stratégies sanitaires et économiques afin de répondre aux besoins d'une population humaine toujours croissante. Dans la forêt tropicale humide de basse altitude de Kianjavato dans le sud-est de Madagascar, 78% des espèces de lémuriens, 83% des espèces de carnivores indigènes et 67% des espèces de chauves-souris frugivores sont menacés d'extinction. Ces trois groupes de mammifères sont généralement chassés dans d'autres régions de Madagascar, mais nous en savons peu sur les niveaux actuels de chasse ou si l'utilisation des ressources forestières affecte significativement le bien-être humain dans cette région. Nous avons conduit une évaluation sanitaire sur 1267 habitants de Kianjavato, ainsi que des entretiens semi-structurés avec des membres de 336 ménages dans 17 communautés de Kianjavato afin d’étudier les interactions entre l’Homme et l’environnement. Nous avons constaté une forte prévalence de la malnutrition chez les enfants et les adolescents. Plus de la moitié de la population âgée de moins de 20 ans souffre d'un retard de croissance, plus de la moitié d’une insuffisance pondérale et plus d'un cinquième d’émaciation. En outre, un résident sur six est anémique. Nous avons constaté que les forêts de Kianjavato fournissent des services écosystémiques essentiels à ces communautés rurales. Comme les forêts de Kianjavato sont altérées pour répondre aux besoins d'une population croissante, ces services écosystémiques à usage direct (tels que la consommation d'animaux sauvages ou des plantes médicinales) ne peuvent plus couvrir les besoins fondamentaux des familles qui y vivent. Une proportion inquiétante de la population de Kianjavato dépend des forêts quant à ses besoins sanitaires, nutritionnels et économiques, cependant ces dernières ne peuvent plus y pourvoir entièrement. Tous les ménages enquêtés (100%) comptent sur la forêt pour la satisfaction de leurs besoins sanitaires. Par ailleurs, l’exploitation de ressources forestières finies (extraction de pierres précieuses) représente 40% de l’économie régionale. La plupart des ménages consommaient très peu d'animaux sauvages (deux animaux par ménage par an) et la grande majorité (83%) des animaux forestiers qu'ils mangeaient n'étaient pas menacés d'extinction. Cependant, 40% de ces animaux forestiers ont été capturés de manière illicite. Certes la chasse ne menace pas actuellement la faune locale mais 16% de la population de Kianjavato reconnaît s’y adonner et 20% souffrent de malnutrition. Les services écosystémiques s’avèrent actuellement insuffisants pour répondre aux besoins des résidents. Il est par conséquent nécessaire de cibler les efforts pour accroître l’accès local au système de santé, ensuite pour améliorer la nutrition et l’économie des ménages (améliorer la production et la stabilité des produits agricoles locaux), et tout ceci dans le but d’augmenter la viabilité à long terme de la chasse, des revenus et de la sécurité alimentaire dans cette région. De tels efforts lorsqu’ils prennent en compte la croissance de la population - et donc ses besoins futurs accrus —peuvent aider à assurer l’utilisation durable des services écosystémiques, à améliorer la santé des populations locales, et en fin de compte, à maintenir l’intégrité des forêts dans lesquelles elles vivent
    corecore