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81.
Jose Javier Ashwini Hinge James Bartram Juying Xu Marie-Dominique Filippi 《Haematologica》2022,107(6):1323
Bone marrow failure syndromes are characterized by ineffective hematopoiesis due to impaired fitness of hematopoietic stem cells. They can be acquired during bone marrow stress or innate and are associated with driver genetic mutations. Patients with a bone marrow failure syndrome are at higher risk of developing secondary neoplasms, including myelodysplastic syndromes and leukemia. Despite the identification of genetic driver mutations, the hematopoietic presentation of the disease is quite heterogeneous, raising the possibility that non-genetic factors contribute to the pathogenesis of the disease. The role of inflammation has emerged as an important contributing factor, but remains to be understood in detail. In this study, we examined the effect of increased transforming growth factor-b (TGFb) signaling, in combination or not with an acute innate immune challenge using polyinosinc:polycytidilic acid (pIC), on the hematopoietic system without genetic mutations. We show that acute rounds of pIC alone drive a benign age-related myeloid cell expansion and increased TGFb signaling alone causes a modest anemia in old mice. In sharp contrast, increased TGFb signaling plus acute pIC challenge result in chronic pancytopenia, expanded hematopoietic stem and progenitor cell pools, and increased bone marrow dysplasia 3-4 months after stress, which are phenotypes similar to human bone marrow failure syndromes. Mechanistically, this disease phenotype is uniquely associated with increased mitochondrial content, increased reactive oxygen species and enhanced caspase-1 activity. Our results suggest that chronic increased TGFb signaling modifies the memory of an acute immune response to drive bone marrow failure without the need for a preexisting genetic insult. Hence, non-genetic factors in combination are sufficient to drive bone marrow failure. 相似文献
82.
83.
Claudia García-Martínez Brbara Olivn-Blzquez Javier Fabra Ana Beln Martínez-Martínez María Cruz Prez-Yus Yolanda Lpez-Del-Hoyo 《JMIR Public Health and Surveillance》2022,8(5)
BackgroundSocial media is now a common context wherein people express their feelings in real time. These platforms are increasingly showing their potential to detect the mental health status of the population. Suicide prevention is a global health priority and efforts toward early detection are starting to develop, although there is a need for more robust research.ObjectiveWe aimed to explore the emotional content of Twitter posts in Spanish and their relationships with severity of the risk of suicide at the time of writing the tweet.MethodsTweets containing a specific lexicon relating to suicide were filtered through Twitter''s public application programming interface. Expert psychologists were trained to independently evaluate these tweets. Each tweet was evaluated by 3 experts. Tweets were filtered by experts according to their relevance to the risk of suicide. In the tweets, the experts evaluated: (1) the severity of the general risk of suicide and the risk of suicide at the time of writing the tweet (2) the emotional valence and intensity of 5 basic emotions; (3) relevant personality traits; and (4) other relevant risk variables such as helplessness, desire to escape, perceived social support, and intensity of suicidal ideation. Correlation and multivariate analyses were performed.ResultsOf 2509 tweets, 8.61% (n=216) were considered to indicate suicidality by most experts. Severity of the risk of suicide at the time was correlated with sadness (ρ=0.266; P<.001), joy (ρ=–0.234; P=.001), general risk (ρ=0.908; P<.001), and intensity of suicidal ideation (ρ=0.766; P<.001). The severity of risk at the time of the tweet was significantly higher in people who expressed feelings of defeat and rejection (P=.003), a desire to escape (P<.001), a lack of social support (P=.03), helplessness (P=.001), and daily recurrent thoughts (P=.007). In the multivariate analysis, the intensity of suicide ideation was a predictor for the severity of suicidal risk at the time (β=0.311; P=.001), as well as being a predictor for fear (β=–0.009; P=.01) and emotional valence (β=0.007; P=.009). The model explained 75% of the variance.ConclusionsThese findings suggest that it is possible to identify emotional content and other risk factors in suicidal tweets with a Spanish sample. Emotional analysis and, in particular, the detection of emotional variations may be key for real-time suicide prevention through social media. 相似文献
84.
The known diterpenes rosmanol (3), rosmaquinone (4), 7-methoxyrosmanol (5), 7-ethoxyrosmanol (6), galdosol (7), and epirosmanol (8) have been obtained by partial synthesis from carnosol (2), an abundant natural product present in Salvia species. The physical and spectroscopic data of these semisynthetic diterpenes were identical to those of authentic natural samples and with data reported in the literature. These abietane diterpenes have very interesting biological activities and are present in the genus Salviain low quantities; thus, the semisynthetic approach described here represents an efficient alternative method to obtain these compounds. Additionally, the known diterpene 16-hydroxyrosmanol (10) and a new aromatic diterpene 11 were obtained from 16-hydroxycarnosol (9) by reaction with Ph3P/NBS in CH2Cl2. The structure of the new compound 11 was established from its spectroscopic data as 12,16-epoxycarnosol. 相似文献
85.
Elena Garcia‐Martin Luis E. Pablo Raquel Herrero Jose R. Ara Jesus Martin Jose M. Larrosa Vicente Polo Julian Garcia‐Feijoo Javier Fernandez 《Acta ophthalmologica. Supplement》2013,91(8):e628-e634
Purpose: To compare axonal loss in ganglion cells detected with spectral‐domain optical coherence tomography (OCT) in eyes of patients with multiple sclerosis (MS) versus healthy control subjects using an artificial neural network (ANN). To analyse the capability of the ANN technique to improve the detection of retinal nerve fibre layer (RNFL) damage in patients with multiple sclerosis. Methods: Patients with multiple sclerosis (n = 106) and age‐matched healthy subjects (n = 115) were enrolled. The Spectralis OCT system was used to obtain the circumpapillary RNFL thickness in both eyes. The 768 RNFL thickness measurements provided by the Spectralis OCT were performed to obtain thickness measurements from 24 uniformly divided locations around the peripapillary RNFL. The performance of the ANN technique for identifying RNFL loss in patients with multiple sclerosis was evaluated. Receiver‐operating characteristic (ROC) curves were used to display the ability of the test to discriminate between MS and healthy eyes in our population. ROC curves obtained using ANN and parameters provided by OCT (mean and 6 sector thicknesses) were compared. Results: The capability of the ANN technique to detect RNFL loss in patients with multiple sclerosis compared with healthy subjects was good. The area under the ROC curve was 0.945. Compared with the OCT‐provided parameters, the ANN had the largest area under the ROC curve. Conclusions: Measurements of RNFL thickness obtained with Spectralis OCT have a good ability to differentiate between healthy and individuals with multiple sclerosis. Based on the area under the ROC curve, the ANN performed better than any single OCT parameter. 相似文献
86.
Ahmed A. Kolkailah Talal Asif Fady H. Iskander Javier Gomez-Valencia Saurabh Malhotra 《Radiology Case Reports》2022,17(9):3270
We report a case of a 44-year-old man with a clinical history of Tetralogy of Fallot status post staged surgical correction with mechanical pulmonic valve replacement who presented with progressive exertional dyspnea in the setting of non-compliance with anticoagulation. In the context of this suggestive clinical presentation, the diagnosis of mechanical pulmonic valve thrombosis (MPVT) was made possible via multimodality imaging, including transthoracic echocardiogram and cardiac computed tomography angiography. Due to the uncommon nature of the condition, the patient was treated with systemic thrombolysis and anticoagulation using evidence-based guidelines, largely extrapolated from left-sided mechanical valve thrombosis. Our case underscores the importance of anticoagulation in MPVT and recognizing the features of MPVT on clinical history, physical examination, and multimodality imaging. It is essential to understand the pivotal role of multimodality imaging in the assessment of MPVT and realize the limitations of available data regarding the management of MPVT in the current era. 相似文献
87.
A small health center is located in Velingara,Senegal.It is approximately 7 o'clock in the morning.In the old,dusty room that constitutes the operating room,a s... 相似文献
88.
Recio-Vega R Ocampo-Gómez G Borja-Aburto VH Moran-Martínez J Cebrian-Garcia ME 《Journal of applied toxicology : JAT》2008,28(5):674-680
Several studies have suggested that human semen quality has declined over the past decades and some of them have associated it with occupational exposure to pesticides. However, most of these studies have not been associated with a reliable exposure level and have been designed mostly as cross-sectional studies. The present work evaluates, in a longitudinal follow-up study, the effect of organophosphate pesticides (OP) at three occupational exposure levels on semen quality. In addition, the study examined the association between OP urinary levels and sperm parameters in exposed and unexposed workers. A total of 139 semen samples from 52 volunteers were assessed. Urinary OP levels were measured by gas-liquid chromatography.The results revealed that the poorest semen quality was found among the subjects with the highest OP exposure and the highest urinary OP levels. Seasonal variations in sperm concentration and sperm count were registered.The results showed a significant decrease in total sperm count among subjects with the highest exposure to OP. Further studies assessing the effects of OP on male reproductive health should be controlled by the variability in human sperm parameters, sperm seasonality, spermatogenesis time and the changing OP exposure level in men highly exposed to OP. 相似文献
89.
目的:报道经玻璃体腔内注射高剂量曲安奈德(triamcinolone acetonide,TA)联合光动力学疗法(photodynamic therapy,PDT)治疗老年性黄斑变性( age related macular degeneration, AMD)的脉络膜新生血管(choroidal neovascularization,CNV)后发生的脉络膜毛细血管萎缩。方法:我们采用非随机回顾性干涉治疗病例。在阿利坎特学院眼科,连续观察51眼(实验组)玻璃体腔内的注射(19.4±2.1)mg/0.1mL TA联合PDT治疗AMD的全部中心凹下型CNV患者,经过2a的随访,检查黄斑部脉络膜毛细血管和视网膜色素上皮细胞(RPE)萎缩情况。同时,采用单独PDT治疗的连续30眼患者作为对照组,其年龄,性别和AMD的CNV类型及大小与实验组相匹配。结果:随访24mo后,在治疗区域21/47眼(45%,实验组)和7/30眼(23%,对照组)发展成黄斑部RPE和脉络膜毛细血管萎缩(P=0.04,卡方检验)。实验组平均最大萎缩区域的直径为(5044±1666)μm,而对照组为(4345±1550)μm。在实验组中,RPE萎缩患者的平均最佳矫正视力为(0.87±0.33),而非RPE萎缩患者的平均最佳矫正视力为(0.66±0.26) (P=0.11,秩和U检验)。结论:玻璃体腔内注射大剂量TA联合PDT治疗可能会增加RPE和脉络膜毛细血管萎缩的风险。 相似文献
90.