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51.
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   
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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   
54.
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   
55.
In order to ascertain whether the high density lipoprotein (HDL) composition of neonates with high serum cholesterol levels (≥2.59 mmol/l or ≥100 mg/dl) differs from that of neonates with normal serum cholesterol levels (<2.59 mmol/l), 548 cord blood samples were examined from full-term newborns of the Toledo Study (Spain) of whom no perinatal factors were known which could alter cord blood lipid levels. Newborns were selected according to the following criteria: single and eutocic delivery with cephalic presentation, gestational age between the beginning of the 37th week and the end of the 41st week, body weight between 2.5 kg and 3.999 kg and an Apgar score of ≥7 and ≥9 at l min and 5 min, respectively. The prevalence of high serum total cholesterol (TC) level was greater (P < 0.02) in females than in males. Newborns with high TC levels had higher triglyceride (P < 0.01), HDL-cholesterol (P < 0.001) and apoprotein (Apo) A-I (P < 0.001) levels, and a higher TC/HDL-cholesterol ratio (P < 0.05), but a lower HDL-cholesterol/Apo A-I ratio (P < 0.05). ANOVA two-way analysis showed a significant effect of gender and serum cholesterol level and a statistical interaction of these two factors upon triglycerides, Apo A-I, and the HDL-cholesterol/Apo A-I ratio. However, HDL-cholesterol and the TC/HDL-cholesterol ratio were higher in neonates (males plus females) with high serum TC but they were not affected by sex. The larger HDL particles in males with high TC levels (HM) should be associated with the higher triglyceride level found in those individuals. Conclusion The composition of high density lipoproteins in newborns is influenced by the serum cholesterol level and by gender. Neonates with high total cholesterol have larger average high density lipoprotein (HDL) particles. If total cholesterol is elevated, HDL from males carries more cholesterol than HDL from females. Received: 26 November 1996 / Accepted: 7 January 1997  相似文献   
56.
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   
57.
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   
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59.
BackgroundThe diagnosis of migraine is mainly clinical and self-reported, which makes additional examinations unnecessary in most cases. Migraine can be subtyped into chronic (CM) and episodic (EM). Despite the very high prevalence of migraine, there are no evidence-based guidelines for differentiating between these subtypes other than the number of days of migraine headache per month. Thus, we consider it timely to perform a systematic review to search for physiological evidence from functional activity (as opposed to anatomical structure) for the differentiation between CM and EM, as well as potential functional biomarkers. For this purpose, Web of Science (WoS), Scopus, and PubMed databases were screened.FindingsAmong the 24 studies included in this review, most of them (22) reported statistically significant differences between the groups of CM and EM. This finding is consistent regardless of brain activity acquisition modality, ictal stage, and recording condition for a wide variety of analyses. That speaks for a supramodal and domain-general differences between CM and EM that goes beyond a differentiation based on the days of migraine per month. Together, the reviewed studies demonstrates that electro- and magneto-physiological brain activity (M/EEG), as well as neurovascular and metabolic recordings from functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), show characteristic patterns that allow to differentiate between CM and EM groups.ConclusionsAlthough a clear brain activity-based biomarker has not yet been identified to distinguish these subtypes of migraine, research is approaching headache specialists to a migraine diagnosis based not only on symptoms and signs reported by patients. Future studies based on M/EEG should pay special attention to the brain activity in medium and fast frequency bands, mainly the beta band. On the other hand, fMRI and PET studies should focus on neural circuits and regions related to pain and emotional processing.  相似文献   
60.

Objectives

To analyze the results of laparoscopic colposacropexy and to achieve a long-lasting support system without recurrences.

Material and methods

From March 2001 to March 2007, we performed laparoscopic colposacropexy in 42 patients. The mean age was 56 years (42-70 years).Patients with prior hysterectomy showed complex vaginal vault prolapse while those without hysterectomy showed prolapse affecting more than one compartment. The 28 women with pelvic uterine prolapse underwent hysterectomy (supracervical hysterectomy in 15 and total hysterectomy in 13). The transperitoneal Burch procedure was carried out in eight patients with stress urinary incontinence.

Results

The mean length of follow-up was 3.5 years (range: 1-6). Surgery was successful in 39 patients (92.8%). Anterior compartment recurrence was observed in one patient and severe lumbar pain associated with postoperative spondylodiscitis in another patient. A third patient required posterior trachelectomy. The mean operating time was 180 min (range: 120-240). The mean length of hospital stay was 2.5 days (range: 2-3).

Conclusions

Laparoscopic colposacropexy is a safe and constantly evolving procedure with longterm durability. This procedure provides similar results to laparotomy but produces fewer vaginal complications.  相似文献   
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