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1.
Bryan E.K. Guevara Suhail Saleem Wan‐Ting Chen Pa‐Fan Hsiao Yu‐Hung Wu 《Journal of cutaneous pathology》2019,46(5):347-352
Lucio phenomenon is an atypical reaction of leprosy, characterized by vasculitic lesions that can mimic antiphospholipid syndrome (APS) clinically. Distinguishing the two can be difficult as antiphospholipid autoantibodies may be present in patients with leprosy. We report on a 32‐year‐old female patient presenting with a sudden onset of fever, hemorrhagic bullae, and skin necrosis on her lower legs. She was treated for APS due to the presence of antiphospholipid antibodies but had an inadequate response. A skin biopsy revealed thrombotic vasculopathy and necrotizing vasculitis associated with aggregation of foam cells in the perivascular area and subcutis, with acid‐fast bacilli in the histiocytes and blood vessel walls. Direct immunofluorescence showed IgM, C3, and fibrinogen deposition in the superficial and deep dermal blood vessels. The pathology confirmed the diagnosis of Lucio phenomenon, and appropriate therapy was given. It is essential to evaluate the patient comprehensively, including clinical, serological, and pathological aspects, to obtain the correct diagnosis. 相似文献
2.
Gutierre Marcela Usberti Telles João Paulo Mota Welling Leonardo Christiaan Rabelo Nícollas Nunes Teixeira Manoel Jacobsen Figueiredo Eberval Gadelha 《Neurosurgical review》2021,44(4):2091-2097
Neurosurgical Review - Cellular response to TBI is a mixture of excitotoxicity, neuroinflammation, and cell death. Biomarkers that can track these lesions and inflammatory processes are being... 相似文献
3.
Flávia Silva Arbex Borim Tiago da Silva Alexandre Anita Liberalesso Neri Roberta de Oliveira Máximo Marcela Fernandes Silva Cesar de Oliveira 《Journal of the American Medical Directors Association》2019,20(1):47-52
Background and objective
There is little epidemiologic evidence considering the combined effect of dynapenia and low 25-hydroxyvitamin D [25 (OH) D] on incident disability. Our aim was to investigate whether the combination of dynapenia and low 25 (OH) D serum levels increases the risk of activities of daily living (ADL) incident disability.Design
Prospective cohort study.Settings
English Longitudinal Study of Aging.Participants
A total of 4630 community-dwelling adults aged 50 years and older without ADL disability at baseline.Measurements
The baseline sample was categorized into 4 groups (ie, nondynapenic/normal 25 (OH) D, low 25 (OH) D only, dynapenic only, and dynapenic/low 25 (OH) D according to their handgrip strength (<26 kg for men and <16 kg for women) and 25 (OH) D (≤50 nmol/L). The outcome was the presence of any ADL disability 2 years after baseline according to the modified Katz Index. Incidence rate ratios (IRRs) adjusted by sociodemographic, behavioral, and clinical characteristics were estimated using Poisson regression.Results
The fully adjusted model showed that older adults with dynapenia only and those with lower serum levels of 25 (OH) D combined with dynapenia had higher incident ADL disability risk compared with nondynapenic and those with normal serum levels of 25 (OH) D. The IRRs for lower 25 (OH) D serum levels combined with dynapenia were higher than for dynapenia only, however, the confidence intervals (CIs) showed similar effect for these 2 groups. The IRRs were 1.31 for low 25(OH) D only (95% CI 0.99–1.74), 1.77 for dynapenia only (95% CI 1.08–2.88), and 1.94 for combined dynapenia and low 25(OH)D (95% CI 1.28–2.94).Conclusions
Dynapenia only and dynapenia combined with low 25 (OH) D serum levels were important risk factors for ADL disability in middle-aged individuals and older adults in 2 years of follow-up. 相似文献4.
Amanda de Carvalho Dutra Lincoln Luís Silva Raíssa Bocchi Pedroso Yolande Pokam Tchuisseu Mariana Teixeira da Silva Marcela Bergamini Joo Felipe Hermann Costa Scheidt Pedro Henrique Iora Rogrio do Lago Franco Catherine Ann Staton Joo Ricardo Nickenig Vissoci Oscar Kenji Nihei Luciano de Andrade 《Global Heart》2021,16(1)
Background:No other disease has killed more than ischemic heart disease (IHD) for the past few years globally. Despite the advances in cardiology, the response time for starting treatment still leads patients to death because of the lack of healthcare coverage and access to referral centers.Objectives:To analyze the spatial disparities related to IHD mortality in the Parana state, Brazil.Methods:An ecological study using secondary data from Brazilian Health Informatics Department between 2013–2017 was performed to verify the IHD mortality. An spatial analysis was performed using the Global Moran and Local Indicators of Spatial Association (LISA) to verify the spatial dependency of IHD mortality. Lastly, multivariate spatial regression models were also developed using Ordinary Least Squares and Geographically Weighted Regression (GWR) to identify socioeconomic indicators (aging, income, and illiteracy rates), exam coverage (catheterization, angioplasty, and revascularization rates), and access to health (access index to cardiologists and chemical reperfusion centers) significantly correlated with IHD mortality. The chosen model was based on p < 0.05, highest adjusted R2 and lowest Akaike Information Criterion.Results:A total of 22,920 individuals died from IHD between 2013–2017. The spatial analysis confirmed a positive spatial autocorrelation global between IDH mortality rates (Moran’s I: 0.633, p < 0.01). The LISA analysis identified six high-high pattern clusters composed by 66 municipalities (16.5%). GWR presented the best model (Adjusted R2: 0.72) showing that accessibility to cardiologists and chemical reperfusion centers, and revascularization and angioplasty rates differentially affect the IHD mortality rates geographically. Aging and illiteracy rate presented positive correlation with IHD mortality rate, while income ratio presented negative correlation (p < 0.05).Conclusion:Regions of vulnerability were unveiled by the spatial analysis where sociodemographic, exam coverage and accessibility to health variables impacted differently the IHD mortality rates in Paraná state, Brazil.Highlights
- The increase in ischemic heart disease mortality rates is related to geographical disparities.
- The IHD mortality is differentially associated to socioeconomic factors, exam coverage, and access to health.
- Higher accessibility to chemical reperfusion centers did not necessarily improve patient outcomes in some regions of the state.
- Clusters of high mortality rate are placed in regions with low amount of cardiologists, income and schooling.
5.
Disruption of Conscious Access in Psychosis Is Associated with Altered Structural Brain Connectivity
Lucie Berkovitch Lucie Charles Antoine Del Cul Nora Hamdani Marine Delavest Samuel Sarrazin Jean-Franois Mangin Pamela Guevara Ellen Ji Marc-Antoine d'Albis Raphaël Gaillard Frank Bellivier Cyril Poupon Marion Leboyer Ryad Tamouza Stanislas Dehaene Josselin Houenou 《The Journal of neuroscience》2021,41(3):513
According to global neuronal workspace (GNW) theory, conscious access relies on long-distance cerebral connectivity to allow a global neuronal ignition coding for conscious content. In patients with schizophrenia and bipolar disorder, both alterations in cerebral connectivity and an increased threshold for conscious perception have been reported. The implications of abnormal structural connectivity for disrupted conscious access and the relationship between these two deficits and psychopathology remain unclear. The aim of this study was to determine the extent to which structural connectivity is correlated with consciousness threshold, particularly in psychosis. We used a visual masking paradigm to measure consciousness threshold, and diffusion MRI tractography to assess structural connectivity in 97 humans of either sex with varying degrees of psychosis: healthy control subjects (n = 46), schizophrenia patients (n = 25), and bipolar disorder patients with (n = 17) and without (n = 9) a history of psychosis. Patients with psychosis (schizophrenia and bipolar disorder with psychotic features) had an elevated masking threshold compared with control subjects and bipolar disorder patients without psychotic features. Masking threshold correlated negatively with the mean general fractional anisotropy of white matter tracts exclusively within the GNW network (inferior frontal-occipital fasciculus, cingulum, and corpus callosum). Mediation analysis demonstrated that alterations in long-distance connectivity were associated with an increased masking threshold, which in turn was linked to psychotic symptoms. Our findings support the hypothesis that long-distance structural connectivity within the GNW plays a crucial role in conscious access, and that conscious access may mediate the association between impaired structural connectivity and psychosis. 相似文献
6.
Roberto Cuevas‐Olguin Eric Esquivel‐Rendon Jorge Vargas‐Mireles Carlos Barajas‐LÌpez Roberto Salgado‐Delgado Nadia Saderi Hugo R. Arias Marco Atzori Marcela Miranda‐Morales 《The European journal of neuroscience》2020,51(3):781-792
Nicotine is the major addictive component of cigarettes, reaching a brain concentration of ~300 nM during smoking of a single cigarette. The prefrontal cortex (PFC) mechanisms underlying temporary changes of working memory during smoking are incompletely understood. Here, we investigated whether 300 nM nicotine modulates γ‐aminobutyric acid (GABA) ergic synaptic transmission from pyramidal neurons of the output layer (V) of the murine medial PFC. We used patch clamp in vitro recording from C57BL/6 mice in the whole‐cell configuration to investigate the effect of nicotine on pharmacologically isolated GABAergic postsynaptic currents (IPSCs) in the absence or presence of methyllycaconitine (MLA) or dihydro‐β‐erythroidine (DHβE), selective antagonists of α7‐ and β2‐containing (α7* and β2*) nicotinic acetylcholine receptors (AChRs), respectively. Our results indicated that nicotine, alone or in the presence of MLA, decreases electrically evoked IPSC (eIPSC) amplitude, whereas in the presence of DHβE, nicotine elicited either an eIPSCs amplitude increase or a decrease. In the presence of DHβE, nicotine increased membrane conductance leaving the paired pulse ratio unchanged in all conditions, suggesting a non‐β2* mediated effect. In the presence of MLA, nicotine decreased the mean spontaneous IPSC (sIPSC) frequency but increased their rise time, suggesting a non‐α7* AChR‐mediated synaptic modulation. Also, in the presence of DHβE, nicotine decreased both eIPSC rise and decay times. No receptors other than α7* and β2* appear to be involved in the nicotine effect. Our results indicate that nicotine smoking concentrations modulate GABAergic synaptic currents through mixed pre‐ and post‐synaptic mechanisms by activation of α7* and β2* AChRs. 相似文献
7.
8.
Vitamin D can be synthesized in the skin via sunlight exposure as well as ingested through diet. Vitamin D deficiency is currently a major global public health issue, with increasing prevalence in both low and high latitude locations. This cross-sectional analysis aimed to compare the intensity of individual Ultraviolet B radiation levels between women of the same ethnicity living in England and Brazil, respectively; and to investigate the association with circulating 25(OH)D concentrations. We analysed data from 135 Brazilian women (England, n = 56, 51° N; Brazil, n = 79, 16° S) recruited for the D-SOL study (Interaction between Vitamin D Supplementation and Sunlight Exposure in Women Living in Opposite Latitudes). Serum 25(OH)D concentrations were analysed by high performance liquid chromatography tandem mass spectrometry (HPLC-MS), individual UVB radiation via UVB dosimeter badges and dietary intake via 4-day diet diaries. Anthropometric, skin phototype, sociodemographic and lifestyle patterns were also assessed. Mean serum 25(OH)D concentration of England residents was significantly lower than Brazil residents. Daily individual UVB radiation level showed a strong significant positive correlation with serum 25(OH)D concentrations. The required UVB radiation to achieve 75 nmol/L was 2.2 SED and 38.8% of the total variance in 25(OH)D concentrations was explained uniquely by daily individual UVB radiation, after controlling for the influence of age and body mass index. Thus, these results highlight the strong positive association between serum 25(OH)D concentrations and individual UVB radiation and the influence of different individual characteristics and behaviours. Collectively, these factors contribute to meaningful, country-specific, public health strategies and policies for the efficient prevention and treatment of vitamin D inadequacy. 相似文献
9.
10.
Angel Fernandez‐Flores Michelle Gatica‐Torres Ftima Tinoco‐Fragoso Linda García‐Hidalgo Elena Monroy Marcela Saeb‐Lima 《Journal of cutaneous pathology》2015,42(2):144-149
Bullous morphea is a rare variant and is not frequently reported. We present three cases of bullous morphea. Although lymphangiectases have been suggested as the most likely mechanism for the development of the bullae in cases of morphea, none of the cases presented with lymphangiectases. To the contrary, all of our cases showed hemorrhagic content in the bullae, which suggests local trauma as a mechanism involved in bulla formation. 相似文献