77 research outputs found

    The Role of Brodmann Area 47 in Acute Stroke Patients with Language Impairment

    Get PDF
    A recent study in chronic stroke patients found that left Brodmann area 47 was among the most commonly lesioned area (more commonly than Brodmann area 44/45) in patients with chronic deficits in reading, naming, and repetition. We hypothesized that the same would not be true in acute stroke; that left BA 44 and 45 would be more commonly associated with these acute lexical deficits. We confirmed this hypothesis and speculate that left BA 47 is an area is critical for recovery of lexical production, perhaps because it can assume lexical production when BA 44/45 are damaged when it is spared

    Areas of Right Hemisphere Ischemia Associated with Impaired Comprehension of Affective Prosody in Acute Stroke

    Get PDF
    We studied 25 participants within 24 hours of acute right hemisphere ischemic stroke and 17 age and education matched hospitalized controls on tests of comprehension of affective prosody. Stroke patients were significantly more impaired than controls in identifying sarcasm versus sincerity in sentences and identifying affective prosody in sentences, monosyllables, and asyllabic utterances, and in discriminating differences in affective prosody in sentences. Impairments in prosodic comprehension were most associated with acute tissue dysfunction in right posterior frontal cortex, posterior inferior temporal cortex, and thalamus

    Asyntactic comprehension and working memory in Broca's aphasia

    Get PDF
    We hypothesized that in acute stroke, some patients show structure-specific, task-independent deficits in sentence comprehension, with chance level of accuracy on passive reversible sentences, more impaired comprehension of object-cleft than subject-cleft sentences, and more impaired comprehension of reversible than irreversible sentences in both sentence-picture matching and enactment tasks, but that this pattern of "asyntactic comprehension" is associated with impaired working memory rather than dysfunctional tissue in Broca's area as previously proposed. We found that the pattern did exist, but was often independent of both impaired working memory and ischemia in Broca’s area (which were less often independent of one another)

    Socioeconomic status and fertility decline:Insights from historical transitions in Europe and North America

    Get PDF
    The timings of historical fertility transitions in different regions are well understood by demographers, but much less is known regarding their specific features and causes. In the study reported in this paper, we used longitudinal micro-level data for five local populations in Europe and North America to analyse the relationship between socio-economic status and fertility during the fertility transition. Using comparable analytical models and class schemes for each population, we examined the changing socio-economic differences in marital fertility and related these to common theories on fertility behaviour. Our results do not provide support for the hypothesis of universally high fertility among the upper classes in pre-transitional society, but do support the idea that the upper classes acted as forerunners by reducing their fertility before other groups. Farmers and unskilled workers were the latest to start limiting their fertility. Apart from these similarities, patterns of class differences in fertility varied significantly between populations

    The assessment, serial evaluation, and subsequent sequelae of acute kidney injury (ASSESS-AKI) study: design and methods

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The incidence of acute kidney injury (AKI) has been increasing over time and is associated with a high risk of short-term death. Previous studies on hospital-acquired AKI have important methodological limitations, especially their retrospective study designs and limited ability to control for potential confounding factors.</p> <p>Methods</p> <p>The Assessment, Serial Evaluation, and Subsequent Sequelae of Acute Kidney Injury (ASSESS-AKI) Study was established to examine how a hospitalized episode of AKI independently affects the risk of chronic kidney disease development and progression, cardiovascular events, death, and other important patient-centered outcomes. This prospective study will enroll a cohort of 1100 adult participants with a broad range of AKI and matched hospitalized participants without AKI at three Clinical Research Centers, as well as 100 children undergoing cardiac surgery at three Clinical Research Centers. Participants will be followed for up to four years, and will undergo serial evaluation during the index hospitalization, at three months post-hospitalization, and at annual clinic visits, with telephone interviews occurring during the intervening six-month intervals. Biospecimens will be collected at each visit, along with information on lifestyle behaviors, quality of life and functional status, cognitive function, receipt of therapies, interim renal and cardiovascular events, electrocardiography and urinalysis.</p> <p>Conclusions</p> <p>ASSESS-AKI will characterize the short-term and long-term natural history of AKI, evaluate the incremental utility of novel blood and urine biomarkers to refine the diagnosis and prognosis of AKI, and identify a subset of high-risk patients who could be targeted for future clinical trials to improve outcomes after AKI.</p

    Relativistic transport theory of N, \Delta and N^{*}(1440) interacting through σ\sigma, ω\omega and π\pi mesons

    Full text link
    A self-consistent relativistic integral-differential equation of the Boltzmann-Uehling-Uhlenbeck-type for the NN^{*}(1440) resonance is developed based on an effective Lagrangian of baryons interacting through mesons. The closed time-path Green's function technique and semi-classical, quasi-particle and Born approximations are employed in the derivation. The non-equilibrium RBUU-type equation for the NN^{*}(1440) is consistent with that of nucleon's and delta's which we derived before. Thus, we obtain a set of coupled equations for the NN, Δ\Delta and NN^{*}(1440) distribution functions. All the NN^{*}(1440)-relevant in-medium two-body scattering cross sections within the NN, Δ\Delta and NN^{*}(1440) system are derived from the same effective Lagrangian in addition to the mean field and presented analytically, which can be directly used in the study of relativistic heavy-ion collisions. The theoretical prediction of the free pppp(1440)pp \to pp^{*}(1440) cross section is in good agreement with the experimental data. We calculate the in-medium N+NN+NN + N \to N + N^{*}, N+NN+NN^{*} + N \to N + N and N+NN+NN^{*} + N \to N^{*} + N cross sections in cold nuclear matter up to twice the nuclear matter density. The influence of different choices of the NNN^{*}N^{*} coupling strengths, which can not be obtained through fitting certain experimental data, are discussed. The results show that the density dependence of predicted in-medium cross sections are sensitive to the NNN^{*}N^{*} coupling strengths used. An evident density dependence will appear when a large scalar coupling strength of gNNσg_{N^{*}N^{*}}^{\sigma} is assumed.Comment: 64 pages, Latex, 13 PostScript figures include

    Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

    Get PDF
    The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

    Disparities in death:Inequality in cause-specific infant and child mortality in Stockholm, 1878-1926

    No full text
    <b>Background</b>: The decline of child mortality during the late 19th century is one of the most significant demographic changes in human history. However, there is evidence suggesting that the substantial reductions in mortality during the era did little to reduce mortality inequality between socioeconomic groups. <b>Objective</b>: The aim of this study is to examine the development of socioeconomic inequalities in cause-specific infant and child mortality during Stockholm's demographic transition. <b>Methods</b>: Using an individual-level longitudinal population register for Stockholm, Sweden, between 1878 and 1926, I estimate Cox proportional hazards models to study how inequality in cause-specific hazards of dying from six categories of causes varied over time. The categories included are 1) airborne and 2) food and waterborne infectious diseases, 3) other infectious diseases, 4) noninfectious diseases and accidents, 5) perinatal causes, and 6) unspecified causes. <b>Results</b>: The results show that class differentials in nearly all causes of death converged during the demographic transition. The only exception was the airborne infectious disease category, for which the gap between white-collar and unskilled blue-collar workers widened over time. <b>Conclusions</b>: The results demonstrate that, even in a context of falling mortality and a changing epidemiological environment, higher socioeconomic groups were able to maintain a health advantage for their children by reducing their risks of dying from airborne disease to a greater extent than other groups. Potential explanations for these patterns are suggested, as well as suggestions for future research. <b>Contribution</b>: This is the first paper to use individual-level cause-of-death data to study the long-term trends in inequality of cause-specific child mortality during the demographic transition
    corecore