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21.

Objecive

To clarify the neuroimaging findings of children with acute flaccid myelitis during an outbreak of EV-D68 infection.

Methods

We performed a detailed review of the spinal and cranial MRI results of 54 children with acute flaccid myelitis. We focused on the range of longitudinal lesions, the localization and appearance of lesions within a horizontal section, Gadolinium-enhancement, and changes over time.

Results

All children had longitudinal spinal lesions involving central gray matter. Twenty-six children had lesions spanning the entire spine. Six of them had weakness in all limbs, whereas seven had weakness of only one limb. Thirty-eight children had lesions in both gray and white matter and limb weakness tended to be more severe in these children. During the acute period, spinal lesions showed bilateral ill-defined widespread T2 hyperintensity. During the subacute period, lesions were well defined and confined to the anterior horn. The distribution of limb weakness was correlated with the appearance of lesions during the subacute period. Gadolinium enhancement was performed in 37 children, and enhancement was seen in the cauda equina in 29 children. Enhancement was infrequent within 2?days after onset but was seen in almost all children thereafter. Twenty-two children had brainstem lesions continuous with spinal lesions.

Conclusion

Extensive longitudinal spinal lesions were characteristic in children with acute flaccid myelitis. Lesions were usually bilateral and widespread during the acute period, whereas localization to the anterior horn could become obvious. Although enhancement of the cauda equina was often observed, its appearance was sometimes delayed.  相似文献   
22.
IntroductionA significant proportion of women report a reduction of symptoms over time—even without treatment—yet the natural progression of vulvodynia and which factors may explain decrease vs persistence of pain remain unclear.AimTo identify subgroups of pain trajectories in women with vulvodynia and to predict these different trajectories by treatments undertaken, pain characteristics, and psychosocial factors.MethodsData on pain intensity, treatments undertaken, pain characteristics, and psychosocial factors were collected 3 times over a 7-year period from 173 women who screened positive for vulvodynia. Latent class growth analysis was conducted to identify homogeneous subgroups with distinct pain trajectories. A multivariate binomial logistic regression was used to examine whether treatments, pain characteristics, and psychosocial factors predicted these trajectories.Main Outcome MeasureThe main outcome was pain intensity (0–10), measured at 3 time points with the numerical rating scale.Results2 pain trajectories were identified: 1 where pain persisted (28.9%), and 1 where pain decreased over time (71.1%). Whether a treatment had been undertaken was not predictive of the course of pain over time. Women who were older at first pain onset, had pain at another location than the entrance of the vagina, and reported more anxiety were more likely to have a persistent pain trajectory relative to the decreased pain trajectory.Clinical ImplicationsFindings suggest that the evolution of pain differs among women with vulvodynia depending on pain characteristics and anxiety.Strengths & LimitationsStrengths of the study include the 7-year longitudinal design to examine the natural history of provoked vestibulodynia and the inclusion of biopsychosocial factors as predictors of pain trajectories. However, women with major medical and psychiatric illnesses or deep dyspareunia were not included, and, thus, these factors could not be examined as predictors.ConclusionAssessing baseline characteristics associated with different pain trajectories during medical visits could have positive implications for the management of vulvodynia.Pâquet M, Vaillancourt-Morel M-P, Jodouin J-F, et al. Pain Trajectories and Predictors: A 7-Year Longitudinal Study of Women With Vulvodynia. J Sex Med 2019;16:1606–1614.  相似文献   
23.
目的 探索布鲁氏杆菌A19疫苗株全基因组的结构、分子生物学的功能,并对其生物信息学进行研究。方法 采用Illumina Hiseq 4000和PacBio对A19进行全基因组测序,并与GenBank 上的8株菌进行比较基因组学解析。A19基因组3 286 167 bp, 预测3 371个基因,GC含量57.25%。通过注释COG库,对应基因有2 560个,将其归入22类COG中;根据比对KEGG库,得到2 544个基因,共参与33类代谢通路。结果 综合两个数据库结果发现,大多数A19预测基因中的基因功能主要与膜运输、氨基酸转运及碳水化合物代谢有关。结论 通过分析发现, A19和猪羊牛种布鲁氏菌之间存在一定差异,并找出牛种毒力基因。本实验通过测序A19全基因组,为布鲁菌疫苗的研究提供思路。  相似文献   
24.
Purpose: This study explored the predictors of the outcomes of turnover and occupation attrition intentions for speech-language pathologists. The researchers examined the mediating effects of job satisfaction and strain on the relationship between stress and the latter outcomes. Additionally, the researchers examined the importance of embeddedness in predicting turnover intentions after accounting for stress, strain and job satisfaction.

Method: An online questionnaire was used to explore turnover and attrition intentions in 293 Australian speech–language pathologists.

Result: Job satisfaction contributed to a significant indirect effect on the stress and turnover intention relationship, however strain did not. There was a significant direct effect between stress and turnover intention after accounting for covariates. Embeddedness and the perceived availability of alternative jobs were also found to be significant predictors of turnover intentions. The mediating model used to predict turnover intentions also predicted occupation attrition intentions. The effect of stress on occupation attrition intentions was indirect in nature, the direct effect negated by mediating variables. Qualitative data provided complementary evidence to the quantitative model.

Conclusion: The findings indicate that the proposed parsimonious model adequately captures predictors of speech–language pathologists’ turnover and occupation attrition intentions. Workplaces and the profession may wish to consider these retention factors.  相似文献   

25.
Bilayer hydrogels with a soft cartilage‐like layer and a stiff bone‐like layer embedded with human mesenchymal stem cells (hMSCs) are promising for osteochondral tissue engineering. The goals of this work were to evaluate the effects of dynamic compressive loading (2.5% applied strain, 1 Hz) on osteogenesis in the stiff layer and spatially map local mechanical responses (strain, stress, hydrostatic pressure, and fluid velocity). A bilayer hydrogel was fabricated from soft (24 kPa) and stiff (124 kPa) poly (ethylene glycol) hydrogels. With hMSCs embedded in the stiff layer, osteogenesis was delayed under loading evident by lower OSX and OPN expressions, alkaline phosphatase activity, and collagen content. At Day 28, mineral deposits were present throughout the stiff layer without loading but localized centrally and near the interface under loading. Local strains mapped by particle tracking showed substantial equivalent strain (~1.5%) transferring to the stiff layer. When hMSCs were cultured in stiff single‐layer hydrogels subjected to similar strains, mineralization was inhibited. Finite element analysis revealed that hydrostatic pressures ≥~600 Pa correlated to regions lacking mineralization in both hydrogels. Fluid velocities were low (~1–10 nm/s) in the hydrogels with no apparent correlation to mineralization. Mineralization was recovered by inhibiting ERK1/2, indicating cell‐mediated inhibition. These findings suggest that high strains (~1.5%) combined with higher hydrostatic pressures negatively impact osteogenesis, but in a manner that depends on the magnitude of each mechanical response. This work highlights the importance of local mechanical responses in mediating osteogenesis of hMSCs in bilayer hydrogels being studied for osteochondral tissue engineering.  相似文献   
26.
Especially individuals with mental disorders might experience an escalation of psychopathological symptoms during the COVID-19 pandemic. Therefore, we investigated the role of anxiety, depressive, and other mental disorders for levels and longitudinal changes of COVID-19-related fear, anxiety and depressive symptoms during the first months of the COVID-19 pandemic in Germany. In a longitudinal observational design with four assessment waves from March, 27th until June, 15th 2020, a total of 6,551 adults from Germany was assessed. 4,175 individuals participated in one, 1,070 in two, 803 in three, and 503 in all four waves of data collection. Multilevel analyses revealed that across all assessment waves, COVID-19-related fear, anxiety, and depressive symptoms were significantly higher in individuals with vs. without anxiety, depressive, and other mental disorders. All symptoms decreased on average over time, and this decrease was significantly stronger in individuals with vs. without anxiety disorders, and particularly driven by individuals with generalized anxiety disorder. Our findings suggest that individuals with mental disorders, especially anxiety disorders – and in particular those with a generalized anxiety disorder – seem to be vulnerable to experience psychological strain in the context of the pandemic, might likely overestimate potential threat, and should be targeted by preventive and therapeutic interventions.  相似文献   
27.
Background and purposeTo determine the diagnostic value of bright spotty lesions (BSLs) for aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (NMOSDAQP4+), the predictive value of axial-BSLs for AQP4-IgG seropositivity, and the radio-clinical differences in NMOSDAQP4+ patients with and without axial-BSLs.Materials and methodsRetrospective study that included patients aged  16 years, with a first acute spinal cord syndrome between 2005 and 2018 and abnormal spinal cord MRI with axial and sagittal T2 sequences. Patients with MRI findings consistent with compressive myelopathy were excluded. All spinal cord MRI were retrospectively evaluated for the presence of BSLs by 2 radiologists blinded to the diagnosis of acute myelopathy.ResultsA total of 82 patients were included; 15 aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder patients (NMOSDAQP4+), and 67 other patients, considered as the other causes of myelopathy (OM) group. The specificity of axial-BSLs for NMOSDAQP4+ patients was 94.0% (95% CI [85.6 to 97.7]). The sensitivity was 40.0% (95% CI [19.8 to 64.3]). In the multivariable analysis, the only MRI characteristic associated with AQP4-IgG positivity was the presence of axial-BSLs (OR: 9.2, 95% CI [1.2 to 72.9]; P = 0.022). In NMOSDAQP4+ patients, the median of cord expansion ratio was higher with axial-BSL (1.2, IQR [1.1–1.3]) than without axial-BSL (1.1, IQR [1.0–1.2]; P = 0.046).ConclusionAfter a first acute spinal cord syndrome, the presence of axial-BSLs on spinal cord MRI seems very specific for NMOSDAQP4+ and seems to be a predictor radiological marker of AQP4-IgG positivity.  相似文献   
28.
BackgroundIn patients with systemic lupus erythematosus (SLE), left ventricle diastolic dysfunction (LVDD) may be the only manifestation of cardiac involvement in anticipation of systolic dysfunction. It has been seen that myocardial deformation of the left atrium (LA), through the LA global longitudinal strain (LAGLS), may be useful in assessing diastolic function.ObjectiveTo evaluate LA function through myocardial deformation in patients with LES, and compare the LA strain in patients with active, inactive and controls.MethodsFifty patients with SLE were included and compared with 50 healthy controls paired by age and gender. Myocardial deformation was measured by transthoracic echocardiogram, to investigate the LAGLS, the strain of the three phases of the LA cycle and the strain rate. The differences between groups were compared in univariate analysis.ResultsLAGLS in SLE patients was less than in the controls (41.6% vs. 50.5%; p = .02), and in the 3 phases of the LA cycle. There were no differences in the LA strain rate in both groups (SLE 2.5 s?1 vs. controls 2.75 s?1; p = .1). It was also found that the LAGLS was lesser in active patients than controls and inactive.ConclusionsSLE patients have lower myocardial deformation of the LA, which is expressed as a lower diastolic function correlating with early subclinical myocardial damage.  相似文献   
29.
ObjectivesThis study sought to identify the factors associated with incident atrial fibrillation (AF) in a well-characterized heart failure with preserved ejection fraction (HFpEF) population, with special focus on left atrial (LA) strain.BackgroundAF is associated with HFpEF, with adverse consequences. Effective risk evaluation might allow the initiation of protective strategies.MethodsClinical evaluation and echocardiography, including measurements of peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and LA volume index (LAVI), were obtained in 170 patients with symptomatic HFpEF (mean age, 65 ± 8 years), free of baseline AF. AF was identified by standard 12-lead electrocardiogram, review of relevant medical records (including Holter documentation), and surveillance with a portable single-lead electrocardiogram device over 2 weeks. Results were validated in the 103 patients with HFpEF from the Karolinska-Rennes (KaRen) study.ResultsOver a median follow-up of 49 months, incident AF was identified in 39 patients (23%). Patients who developed AF were older; had higher clinical risk scores, brain natriuretic peptide, creatinine, LAVI, and LV mass; lower LA strain and exercise capacity; and more impaired LV diastolic function. PACS, PALS, and LAVI were the most predictive parameters for AF (area under receiver-operating characteristic curve: 0.76 for PACS, 0.71 for PALS, and 0.72 for LAVI). Nested Cox regression models showed that the predictive value of PACS and PALS was independent from and incremental to clinical data, LAVI, and E/e’ ratio. Classification and regression trees analysis identified PACS ≤12.7%, PALS ≤29.4%, and LAVI >34.3 ml/m2 as discriminatory nodes for AF, with a 33-fold greater hazard of AF (p < 0.001) in patients categorized as high risk. The classification and regression trees algorithm discriminated high and low AF risk in the validation cohort.ConclusionsPACS and PALS provide incremental predictive information about incident AF in HFpEF. The inclusion of these LA strain components to the diagnostic algorithm may help guide screening and further monitoring for AF risk in this population.  相似文献   
30.
Fetal, infant, and toddler neuroimaging is commonly thought of as a development of modern times (last two decades). Yet, this field mobilized shortly after the discovery and implementation of MRI technology. Here, we provide a review of the parallel advancements in the fields of fetal, infant, and toddler neuroimaging, noting the shifts from clinical to research use, and the ongoing challenges in this fast-growing field. We chronicle the pioneering science of fetal, infant, and toddler neuroimaging, highlighting the early studies that set the stage for modern advances in imaging during this developmental period, and the large-scale multi-site efforts which ultimately led to the explosion of interest in the field today. Lastly, we consider the growing pains of the community and the need for an academic society that bridges expertise in developmental neuroscience, clinical science, as well as computational and biomedical engineering, to ensure special consideration of the vulnerable mother-offspring dyad (especially during pregnancy), data quality, and image processing tools that are created, rather than adapted, for the young brain.  相似文献   
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