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The family Arecaceae includes 181 genera and 2,600 species with a high diversity in physical characteristics. Areca plants, commonly palms, which are able to grow in nearly every type of habitat, prefer tropical and subtropical climates. The most studied species Areca catechu L. contains phytochemicals as phenolics and alkaloids with biological properties. The phenolics are mainly distributed in roots followed by fresh unripe fruits, leaves, spikes, and veins, while the contents of alkaloids are in the order of roots, fresh unripe fruits, spikes, leaves, and veins. This species has been reputed to provide health effects on the cardiovascular, respiratory, nervous, metabolic, gastrointestinal, and reproductive systems. However, in many developing countries, quid from this species has been associated with side effects, which include the destruction of the teeth, impairment of oral hygiene, bronchial asthma, or oral cancer. Despite these side effects, which are also mentioned in this work, the present review collects the main results of biological properties of the phytochemicals in A. catechu. This study emphasizes the in vitro and in vivo antioxidant, antimicrobial, anticancer, and clinical effectiveness in humans. In this sense, A. catechu have demonstrated effectiveness in several reports through in vitro and in vivo experiments on disorders such as antimicrobial, antioxidant, or anticancer. Moreover, our findings demonstrate that this species presents clinical effectiveness on neurological disorders. Hence, A. catechu extracts could be used as a bioactive ingredient for functional food, nutraceuticals, or cosmeceuticals. However, further studies, especially extensive and comprehensive clinical trials, are recommended for the use of Areca in the treatment of diseases.  相似文献   
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Astrocytes perform important housekeeping functions in the nervous system including maintenance of adequate neuronal excitability, although the regulatory mechanisms are currently poorly understood. The astrocytic Ca2+/calmodulin-activated phosphatase calcineurin (CaN) is implicated in the development of reactive gliosis and neuroinflammation, but its roles, including the control of neuronal excitability, in healthy brain is unknown. We have generated a mouse line with conditional knockout (KO) of CaN B1 (CaNB1) in glial fibrillary acidic protein-expressing astrocytes (a stroglial c alcin eurin KO [ACN-KO]). Here, we report that postnatal and astrocyte-specific ablation of CaNB1 did not alter normal growth and development as well as adult neurogenesis. Yet, we found that specific deletion of astrocytic CaN selectively impairs intrinsic neuronal excitability in hippocampal CA1 pyramidal neurons and cerebellar granule cells (CGCs). This impairment was associated with a decrease in after hyperpolarization in CGC, while passive properties were unchanged, suggesting impairment of K+ homeostasis. Indeed, blockade of Na+/K+-ATPase (NKA) with ouabain phenocopied the electrophysiological alterations observed in ACN-KO CGCs. In addition, NKA activity was significantly lower in cerebellar and hippocampal lysates and in pure astrocytic cultures from ACN-KO mice. While no changes were found in protein levels, NKA activity was inhibited by the specific CaN inhibitor FK506 in both cerebellar lysates and primary astroglia from control mice, suggesting that CaN directly modulates NKA activity and in this manner controls neuronal excitability. In summary, our data provide formal evidence for the notion that astroglia is fundamental for controlling basic neuronal functions and place CaN center-stage as an astrocytic Ca2+-sensitive switch.  相似文献   
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While some children with acute lymphoblastic leukemia (ALL) have excellent prognoses, the prognosis for adults and children with T cell ALL is more guarded. Treatment for T-ALL is heavily dependent upon antimetabolite chemotherapeutics, including cytarabine. Targeted inhibition of WEE1 with AZD1775 has emerged as a strategy to sensitize cancer cells to cytarabine and other chemotherapeutics. We sought to determine if this strategy would be effective for T-ALL with clinically relevant anti-leukemia agents. We found that AZD1775 sensitizes T-ALL cells to several traditional anti-leukemia agents, acting synergistically with cytarabine by enhancing DNA damage and apoptosis. In addition to increased phosphorylation of H2AX at serine 139 (γH2AX), AZD1775 led to increased phosphorylation of H2AX at tyrosine 142, a signaling event associated with promotion of apoptosis over DNA repair. In a xenograft model of T-ALL, the addition of AZD1775 to cytarabine slowed leukemia progression and prolonged survival. Inhibition of WEE1 with AZD1775 sensitizes T-ALL to several anti-leukemia agents, particularly cytarabine. Mechanistically, AZD1775 promotes apoptosis over DNA repair in cells treated with cytarabine. These data support the development of clinical trials including AZD1775 in combination with conventional chemotherapy for acute leukemia.  相似文献   
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locStra is an ‐package for the analysis of regional and global population stratification in whole‐genome sequencing (WGS) studies, where regional stratification refers to the substructure defined by the loci in a particular region on the genome. Population substructure can be assessed based on the genetic covariance matrix, the genomic relationship matrix, and the unweighted/weighted genetic Jaccard similarity matrix. Using a sliding window approach, the regional similarity matrices are compared with the global ones, based on user‐defined window sizes and metrics, for example, the correlation between regional and global eigenvectors. An algorithm for the specification of the window size is provided. As the implementation fully exploits sparse matrix algebra and is written in C++, the analysis is highly efficient. Even on single cores, for realistic study sizes (several thousand subjects, several million rare variants per subject), the runtime for the genome‐wide computation of all regional similarity matrices does typically not exceed one hour, enabling an unprecedented investigation of regional stratification across the entire genome. The package is applied to three WGS studies, illustrating the varying patterns of regional substructure across the genome and its beneficial effects on association testing.  相似文献   
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Introduction: Pediatric data related to safety, tolerance, and outcomes of enteral nutrition (EN) for patients requiring extracorporeal membrane oxygenation (ECMO) are lacking. The objectives of this study were to evaluate early nutrition status and timing of EN initiation on survival during pediatric ECMO. Methods: A single center institutional review board–approved retrospective chart review was performed on all pediatric patients requiring ECMO from October 2008 through December 2013. Demographics, ECMO variables, laboratory values, vasoactive inotropic score (VIS), and nutrition data on day 5 (d5) were collected. Patients receiving parenteral nutrition (PN) were compared with those receiving any EN on d5. Analyses were conducted to identify factors influencing survival to completion of ECMO and to discharge. Results: Forty‐nine patients aged 53 ± 76 months met inclusion criteria. Kaplan‐Meier curves demonstrated greater survival to discharge in patients receiving any EN, compared with only receiving PN (P = .031). EN on d5 of ECMO support (P = .040) and a higher percentage of daily energy intake achieved (P = .013) were protective, whereas a higher VIS was associated with increased mortality (P = .010). Multivariable analysis demonstrated EN was no longer associated with survival to discharge (P = .139), whereas energy intake (P = .021) and VIS (P = .013) remained significant. Conclusions: Pediatric patients who received nutrition that was closer to goal energy intake, as well as those who received any EN early during ECMO, had improved survival to hospital discharge.  相似文献   
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Background : This study tested the accuracy of resting energy expenditure (REE) equations among patients who underwent cardiopulmonary bypass and developed/validated a more accurate cardio‐specific equation (CSE). Materials and Methods : Prospective observational cohort of 240 adults (derivation data set, 170 patients; validation data set, 70 patients). REEs were calculated with 6 equations—Penn State 2003a, Penn State 2003b, Ireton‐Jones, Swinamer, Faisy, and American College of Chest Physicians—and results were compared with indirect calorimetry (IC). Multivariable linear regression analysis was used to develop the CSE. Agreement between measured and calculated REEs was assessed with Lin’s concordance correlation coefficient (LCCC), Bland‐Altman plot, and regression analysis. Results : LCCCs present poor agreement between measured and calculated REEs: 0.24 (95% CI, 0.19–0.29), for the Faisy equation; 0.15 (95% CI, 0.1–0.19), Ireton‐Jones; 0.31 (95% CI, 0.25–0.37), Swinamer; 0.17 (95% CI, 0.13–0.21), Penn State 2003a; 0.19 (95% CI, 0.14–0.23), Penn State 2003b; and 0.11 (95% CI, 0.07–0.15), American College of Chest Physicians. Based on the derivation data set, REEs are explained by the following equation: CSE = 616 ? 8 × age in years + 13 × weight in kilograms + 450 if on ventilator + 159 × MV in liters + 145 if on inotropes. Based on the validation study results, the LCCC between IC and the CSE was 0.82 (95% CI, 0.73–0.88). Conclusion : The CSE has adequate precision and could be used for REE estimation for patients undergoing cardiopulmonary bypass if IC is unavailable.  相似文献   
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