Publications by authors named "Hood M"

Repeat induced point mutation (RIP), a mechanism causing hypermutation of repetitive DNA sequences in fungi, has been described as a 'genome defense' which functions to inactivate mobile elements and inhibit their deleterious effects on genome stability. Here we address the interactions between RIP and transposable elements in the Microbotryum violaceum species complex. Ten strains of M.

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Background: The Personality Assessment Inventory (PAI), an overall measure of personality and psychopathology, features a number of dimensions that may be useful in the psychological assessment of bariatric surgery candidates. However, its clinical utility is limited because psychometric properties of the PAI with bariatric surgery candidates have never been evaluated, and normative data for this population have never been published.

Methods: We examined the psychometric properties and clinical utility of the PAI with a large sample of bariatric surgery candidates (n = 546) presenting for evaluation in an urban medical center.

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Understanding what determines the host range of pathogens and the potential for host shifts is of critical importance to controlling their introductions into new environments. The phylogeny of the hosts has been shown to be important: pathogens are more likely to be infectious on hosts closely related to their host-of-origin because of the similar host environments that is shared by descent. The importance of pathogen phylogenies for predicting host range has never been investigated, although a pathogen should also be able to exploit a new host that its close relative can infect.

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Nursing research encompasses a wide array of study areas that often times follow specific groups of patients or patient types. The cohort study design is a useful method to study any group, especially to track outcomes or to evaluate exposure or risk factors. Several different cohort study designs can be applied to the general population or to specific subpopulations or groups, such as those with cardiovascular disease.

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Pleomorphic lipoma is a rare lipocytic neoplasm that most commonly occurs in the head and neck region in middle-aged to elderly men. Clinically, it presents as a slow-growing, well-circumscribed subcutaneous mass. Histopathologically and cytogenetically, it has some features overlapping with other benign and malignant tumors, such as benign spindle cell lipoma, atypical lipomatous tumor, liposarcoma, and malignant fibrous histiocytoma.

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At Time 1 (T1), the authors surveyed 277 unemployed adults using measures of human capital, goal orientation, self-regulation (emotion control, motivation control, work commitment), and job-seeking intensity. At Time 2 (T2), 4 months later, 155 participants indicated their reemployment outcomes in number of job interviews and number of job offers. Using T1 data, the authors tested the predictors of job-seeking intensity and whether self-regulation mediated between goal orientation and job-seeking intensity.

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Background: Host individuals represent an arena in which pathogens compete for resources and transmission opportunities, with major implications for the evolution of virulence and the structure of populations. Studies to date have focused on competitive interactions within pathogen species, and the level of antagonism tends to increase with the genetic distance between competitors. Anther-smut fungi, in the genus Microbotryum, have emerged as a tractable model for within-host competition.

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The genus Silene, studied by Darwin, Mendel and other early scientists, is re-emerging as a system for studying interrelated questions in ecology, evolution and developmental biology. These questions include sex chromosome evolution, epigenetic control of sex expression, genomic conflict and speciation. Its well-studied interactions with the pathogen Microbotryum has made Silene a model for the evolution and dynamics of disease in natural systems, and its interactions with herbivores have increased our understanding of multi-trophic ecological processes and the evolution of invasiveness.

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Microbotryum violaceum, the anther-smut fungus, forms a complex of sibling species which specialize on different plants. Previous studies have shown the presence of partial ecological isolation and F1 inviability, but did not detect assortative mating apart from a high selfing rate. We investigated other post-mating barriers and show that F1 hybrid sterility, the inability of gametes to mate, increased gradually with the increasing genetic distance between the parents.

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In the majority of sexual organisms, reproduction occurs almost exclusively through the combination of distinct and alternate forms, called sexes or mating types. In some fungi, there can be dozens to hundreds of alternate alleles that determine compatible mating types. Such extensive polymorphism is expected to be maintained by balancing selection, and in extreme cases may give rise to trans-specific polymorphism.

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ABSTRACT The ability of Thielaviopsis basicola to survive saprophytically in soil was investigated using root tissue from susceptible hosts as organic substrates. Inoculum densities were lower in soils amended with root tissue than in nonamended controls after 2 and 4 weeks of incubation. The greatest decrease occurred in soils containing the highest concentration of root tissue or in soils in which root tissue included the soluble components of the living root.

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ABSTRACT Initial interactions of Striga asiatica with a susceptible host and non-host plants were examined by histological methods. Haustorial development was initiated when radicles of S. asiatica were placed in contact with host or nonhost roots.

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Host sterilization is a common feature of sexually transmitted diseases (STDs). Because host reproductive failure may free up resources for pathogen reproduction and transmission, theory predicts that selection on sterilizing pathogens will favour maximum virulence (i.e.

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The need to prevent and cure emerging diseases often precludes their continuing study in situ. We present studies on the process of disease emergence by host shifts using the model system of anther-smut disease (Microbotryum violaceum) on the plant genus Silene (Caryophyllaceae). This system has little direct social impact, and it is readily amenable to experimental manipulation.

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Objective: To assess social functioning and facial expression recognition skill in survivors of pediatric brain tumors (BT) as compared to children with juvenile rheumatoid arthritis (JRA).

Methods: The social functioning of 51 survivors of BT and 31 children with JRA was assessed using a facial expression recognition task, questionnaire ratings of social functioning, and an IQ screener.

Results: After controlling for estimated IQ, survivors of BT made significantly more errors interpreting adult facial expressions as compared to children with JRA.

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Background: Using phylogenetic approaches, the expectation that parallel cladogenesis should occur between parasites and hosts has been validated in some studies, but most others provided evidence for frequent host shifts. Here we examine the evolutionary history of the association between Microbotryum fungi that cause anther smut disease and their Caryophyllaceous hosts. We investigated the congruence between host and parasite phylogenies, inferred cospeciation events and host shifts, and assessed whether geography or plant ecology could have facilitated the putative host shifts identified.

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In this review on fungal speciation, we first contrast the issues of species definition and species criteria and show that by distinguishing the two concepts the approaches to studying the speciation can be clarified. We then review recent developments in the understanding of modes of speciation in fungi. Allopatric speciation raises no theoretical problem and numerous fungal examples exist from nature.

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We report the development of 60 microsatellite markers on four species of the fungal complex Microbotryum, causing anther smut of the Caryophyllaceae. Microsatellites were found in four expressed sequence tag (EST) libraries, built from isolates of M. lychnis-dioicae, M.

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Population models of host-parasite interactions predict that when different parasite genotypes compete within a host for limited resources, those that exploit the host faster will be selected, leading to an increase in parasite virulence. When parasites sharing a host are related, however, kin selection should lead to more cooperative host exploitation that may involve slower rates of parasite reproduction. Despite their potential importance, studies that assess the prevalence of multiple genotype infections in natural populations remain rare, and studies quantifying the relatedness of parasites occurring together as natural multiple infections are particularly scarce.

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Purpose: To develop a method for fat suppression in myocardial delayed enhancement (MDE) studies that achieves effective signal intensity reduction in fat but does not perturb myocardial signal suppression.

Materials And Methods: A new approach to fat suppression that uses a spectrally-selective inversion-recovery (SPEC-IR) tip-up radio frequency (RF) pulse following the conventional nonselective IR RF pulse together with a second SPEC-IR RF pulse is proposed. The tip-up pulse restores the fat longitudinal magnetization after the nonselective IR pulse and allows the fat magnetization to recover more fully toward its equilibrium value, providing for better fat suppression by the second SPEC-IR RF pulse.

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Objectives: The purpose of this study was to evaluate the feasibility and safety of a novel technology that uses energy transfer from an ultrasound transmitter to achieve cardiac stimulation without the use of a pacing lead in humans.

Background: To overcome the limitations of pacemaker leads, a new technology enabling stimulation without the use of a lead is desirable.

Methods: A steerable bipolar electrophysiology catheter incorporating a receiver electrode into the tip and circuitry to convert ultrasound energy to electrical energy was inserted transvenously into the heart.

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Background: The basidiomycete fungus Microbotryum violaceum is responsible for the anther-smut disease in many plants of the Caryophyllaceae family and is a model in genetics and evolutionary biology. Infection is initiated by dikaryotic hyphae produced after the conjugation of two haploid sporidia of opposite mating type. This study describes M.

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Despite important advances in the last few years, the evolution of reproductive isolation (RI) remains an unresolved and critical gap in our understanding of speciation processes. In this study, we investigated the evolution of RI among species of the parasitic fungal species complex Microbotryum violaceum, which is responsible for anther smut disease of the Caryophyllaceae. We found no evidence for significant positive assortative mating by M.

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