1,574 research outputs found
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Reliability and Validity of Instruments for Assessing Perinatal Depression in African Settings: Systematic Review and Meta-Analysis
Background: A major barrier to improving perinatal mental health in Africa is the lack of locally validated tools for identifying probable cases of perinatal depression or for measuring changes in depression symptom severity. We systematically reviewed the evidence on the reliability and validity of instruments to assess perinatal depression in African settings. Methods and Findings: Of 1,027 records identified through searching 7 electronic databases, we reviewed 126 full-text reports. We included 25 unique studies, which were disseminated in 26 journal articles and 1 doctoral dissertation. These enrolled 12,544 women living in nine different North and sub-Saharan African countries. Only three studies (12%) used instruments developed specifically for use in a given cultural setting. Most studies provided evidence of criterion-related validity (20 [80%]) or reliability (15 [60%]), while fewer studies provided evidence of construct validity, content validity, or internal structure. The Edinburgh postnatal depression scale (EPDS), assessed in 16 studies (64%), was the most frequently used instrument in our sample. Ten studies estimated the internal consistency of the EPDS (median estimated coefficient alpha, 0.84; interquartile range, 0.71-0.87). For the 14 studies that estimated sensitivity and specificity for the EPDS, we constructed 2 x 2 tables for each cut-off score. Using a bivariate random-effects model, we estimated a pooled sensitivity of 0.94 (95% confidence interval [CI], 0.68-0.99) and a pooled specificity of 0.77 (95% CI, 0.59-0.88) at a cut-off score of â„9, with higher cut-off scores yielding greater specificity at the cost of lower sensitivity. Conclusions: The EPDS can reliably and validly measure perinatal depression symptom severity or screen for probable postnatal depression in African countries, but more validation studies on other instruments are needed. In addition, more qualitative research is needed to adequately characterize local understandings of perinatal depression-like syndromes in different African contexts
Ambient noise correlation on the Amery Ice Shelf, East Antarctica
The structure of ice shelves is important for modelling the dynamics of ice flux from the continents to the oceans. While other, more traditional techniques provide many constraints, passive imaging with seismic noise is a complementary tool for studying and monitoring ice shelves. As a proof of concept, here we study noise cross-correlations and autocorrelations on the Amery Ice Shelf, East Antarctica. We find that the noise field on the ice shelf is dominated by energy trapped in a low-velocity waveguide caused by the water layer below the ice. Within this interpretation, we explain spectral ratios of the noise cross-correlations as P-wave resonances in the water layer, and obtain an independent estimate of the water-column thickness, consistent with other measurements. For stations with noise dominated by elastic waves, noise autocorrelations also provide similar results. High-frequency noise correlations also require a 50-m firn layer near the surface with P-wave velocity as low as 1 km s^(â1). Our study may also provide insight for future planetary missions that involve seismic exploration of icy satellites such as Titan and Europa
Characterization of the cytokinin-responsive transcriptome in rice
Abstract Background Cytokinin activates transcriptional cascades important for development and the responses to biotic and abiotic stresses. Most of what is known regarding cytokinin-regulated gene expression comes from studies of the dicotyledonous plant Arabidopsis thaliana. To expand the understanding of the cytokinin-regulated transcriptome, we employed RNA-Seq to analyze gene expression in response to cytokinin in roots and shoots of the monocotyledonous plant rice. Results We identified over 4,600 and approximately 2,400 genes differentially expressed in response to cytokinin in roots and shoots respectively. There were some similarities in the sets of cytokinin-regulated genes identified in rice and Arabidopsis, including an up-regulation of genes that act to reduce cytokinin function. Consistent with this, we found that the preferred DNA-binding motif of a rice type-B response regulator is similar to those from Arabidopsis. Analysis of the genes regulated by cytokinin in rice revealed a large number of transcription factors, receptor-like kinases, and genes involved in protein degradation, as well as genes involved in development and the response to biotic stress. Consistent with the over-representation of genes involved in biotic stress, there is a substantial overlap in the genes regulated by cytokinin and those differentially expressed in response to pathogen infection, suggesting that cytokinin plays an integral role in the transcriptional response to pathogens in rice, including the induction of a large number of WRKY transcription factors. Conclusions These results begin to unravel the complex gene regulation after cytokinin perception in a crop of agricultural importance and provide insight into the processes and responses modulated by cytokinin in monocots
Collagen Based Multicomponent Interpenetrating Networks as Promising Scaffolds for 3D Culture of Human Neural Stem Cells, Human Astrocytes, and Human Microglia
This work describes for the first time the fabrication and characterization of multicomponent interpenetrating networks composed of collagen I, hyaluronic acid, and poly(ethylene glycol) diacrylate for the 3D culture of human neural stem cells, astrocytes, and microglia. The chemical composition of the scaffolds can be modulated while maintaining values of complex moduli within the range of the mechanical performance of brain tissue (âŒ6.9 kPa) and having cell viability exceeding 84%. The developed scaffolds are a promising new family of biomaterials that can potentially serve as 3D in vitro models for studying the physiology and physiopathology of the central nervous system
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Biomarkers of Dairy Fatty Acids and Risk of Cardiovascular Disease in the MultiâEthnic Study of Atherosclerosis
Background: Evidence regarding the role of dairy fat intake in cardiovascular disease (CVD) has been mixed and inconclusive. Most earlier studies have used selfâreported measures of dietary intake and focused on relatively racially homogeneous populations. Circulating biomarkers of dairy fat in a multiethnic cohort provide objective measures of dairy fat intake and facilitate conclusions relevant to populations with different diets and susceptibility to CVD. Methods and Results: In a multiethnic cohort of 2837 US adults aged 45 to 84 years at baseline (2000â2002), phospholipid fatty acids including 15:0, 14:0, and transâ16:1n7 were measured using standardized methods, and the incidence of CVD prospectively adjudicated. Selfâreported wholeâfat dairy and butter intakes had strongest associations with 15:0, rather than 14:0 or transâ16:1n7. In multivariate models including demographics and lifestyle and dietary habits, each SDâunit of 15:0 was associated with 19% lower CVD risk (hazard ratio [95% CI] 0.81 [0.68 to 0.98]) and 26% lower coronary heart disease (CHD) risk (0.74 [0.60 to 0.92]). Associations were strengthened after mutual adjustment for 14:0 and transâ16:1nâ7 and were similar after adjustment for potential mediators. Plasma phospholipid 14:0 and transâ16:1nâ7 were not significantly associated with incident CVD or CHD. All findings were similar in white, black, Hispanic, and Chinese American participants. Conclusion: Plasma phospholipid 15:0, a biomarker of dairy fat, was inversely associated with incident CVD and CHD, while no association was found with phospholipid 14:0 and transâ16:1nâ7. These findings support the need for further investigation of CVD effects of dairy fat, dairyâspecific fatty acids, and dairy products in general
Improved Functional Outcome After Peripheral Nerve Stimulation of the Impaired Forelimb Post-stroke
Lack of blood flow to the brain, i.e., ischemic stroke, results in loss of nerve cells and therefore loss of function in the effected brain regions. There is no effective treatment to improve lost function except restoring blood flow within the first several hours. Rehabilitation strategies are widely used with limited success. The purpose of this study was to examine the effect of electrical stimulation on the impaired upper extremity to improve functional recovery after stroke. We developed a rodent model using an electrode cuff implant onto a single peripheral nerve (median nerve) of the paretic forelimb and applied daily electrical stimulation. The skilled forelimb reaching test was used to evaluate functional outcome after stroke and electrical stimulation. Anterograde axonal tracing from layer V pyramidal neurons with biotinylated dextran amine was done to evaluate the formation of new neuronal connections from the contralesional cortex to the deafferented spinal cord. Rats receiving electrical stimulation on the median nerve showed significant improvement in the skilled forelimb reaching test in comparison with stroke only and stroke with sham stimulation. Rats that received electrical stimulation also exhibited significant improvement in the latency to initiate adhesive removal from the impaired forelimb, indicating better sensory recovery. Furthermore, axonal tracing analysis showed a significant higher midline fiber crossing index in the cervical spinal cord of rats receiving electrical stimulation. Our results indicate that direct peripheral nerve stimulation leads to improved sensorimotor recovery in the stroke-impaired forelimb, and may be a useful approach to improve post-stroke deficits in human patients
Interdependency of EGF and GLP-2 Signaling in Attenuating Mucosal Atrophy in a Mouse Model of Parenteral Nutrition
BACKGROUND & AIMS: Total parenteral nutrition (TPN), a crucial treatment for patients who cannot receive enteral nutrition, is associated with mucosal atrophy, barrier dysfunction, and infectious complications. Glucagon-like peptide-2 (GLP-2) and epidermal growth factor (EGF) improve intestinal epithelial cell (IEC) responses and attenuate mucosal atrophy in several TPN models. However, it remains unclear whether these 2 factors use distinct or overlapping signaling pathways to improve IEC responses. We investigated the interaction of GLP-2 and EGF signaling in a mouse TPN model and in patients deprived of enteral nutrition.
METHODS: Adult C57BL/6J, IEC-Egfrknock out (KO) and IEC-pik3r1KO mice receiving TPN or enteral nutrition were treated with EGF or GLP-2 alone or in combination with reciprocal receptor inhibitors, GLP-2(3-33) or gefitinib. Jejunum was collected and mucosal atrophy and IEC responses were assessed by histologic, gene, and protein expression analyses. In patients undergoing planned looped ileostomies, fed and unfed ileum was analyzed.
RESULTS: Enteral nutrient deprivation reduced endogenous EGF and GLP-2 signaling in mice and human beings. In the mouse TPN model, exogenous EGF or GLP-2 attenuated mucosal atrophy and restored IEC proliferation. The beneficial effects of EGF and GLP-2 were decreased upon Gefitinib treatment and in TPN-treated IEC-EgfrKO mice, showing epidermal growth factorâreceptor dependency for these IEC responses. By contrast, in TPN-treated IEC-pi3kr1KO mice, the beneficial actions of EGF were lost, although GLP-2 still attenuated mucosal atrophy.
CONCLUSIONS: Upon enteral nutrient deprivation, exogenous GLP-2 and EGF show strong interdependency for improving IEC responses. Understanding the differential requirements for phosphatidylinositol 3-kinase/phosphoAKT (Ser473) signaling may help improve future therapies to prevent mucosal atrophy
Interdependency of EGF and GLP-2 Signaling in Attenuating Mucosal Atrophy in a Mouse Model of Parenteral Nutrition
Background & Aims: Total parenteral nutrition (TPN), a crucial treatment for patients who cannot receive enteral nutrition, is associated with mucosal atrophy, barrier dysfunction, and infectious complications. Glucagon-like peptide-2 (GLP-2) and epidermal growth factor (EGF) improve intestinal epithelial cell (IEC) responses and attenuate mucosal atrophy in several TPN models. However, it remains unclear whether these 2 factors use distinct or overlapping signaling pathways to improve IEC responses. We investigated the interaction of GLP-2 and EGF signaling in a mouse TPN model and in patients deprived of enteral nutrition. Methods: Adult C57BL/6J, IEC-Egfrknock out (KO) and IEC-pik3r1KO mice receiving TPN or enteral nutrition were treated with EGF or GLP-2 alone or in combination with reciprocal receptor inhibitors, GLP-2(3-33) or gefitinib. Jejunum was collected and mucosal atrophy and IEC responses were assessed by histologic, gene, and protein expression analyses. In patients undergoing planned looped ileostomies, fed and unfed ileum was analyzed. Results: Enteral nutrient deprivation reduced endogenous EGF and GLP-2 signaling in mice and human beings. In the mouse TPN model, exogenous EGF or GLP-2 attenuated mucosal atrophy and restored IEC proliferation. The beneficial effects of EGF and GLP-2 were decreased upon Gefitinib treatment and in TPN-treated IEC-EgfrKO mice, showing epidermal growth factorĂąreceptor dependency for these IEC responses. By contrast, in TPN-treated IEC-pi3kr1KO mice, the beneficial actions of EGF were lost, although GLP-2 still attenuated mucosal atrophy. Conclusions: Upon enteral nutrient deprivation, exogenous GLP-2 and EGF show strong interdependency for improving IEC responses. Understanding the differential requirements for phosphatidylinositol 3-kinase/phosphoAKT (Ser473) signaling may help improve future therapies to prevent mucosal atrophy. Keywords: Total Parenteral Nutrition, EGF, GLP-2, EGFR, PI3K, Mucosal Atroph
Outcomes of multimodal therapy in a large series of patients with anaplastic thyroid cancer
Background The role of radiotherapy (RT) in the treatment of patients with anaplastic thyroid cancer (ATC) for local tumor control is critical because mortality often is secondary to complications of tumor volume rather than metastatic disease. Herein, the authors report the long-term outcomes of RT for patients with ATC. Methods A total of 104 patients with histologically confirmed ATC were identified who presented to the study institution between 1984 and 2017 and who received curative-intent or postoperative RT. Locoregional progression-free survival (LPFS), overall survival (OS), and distant metastasis-free survival were assessed. Results The median age of the patients was 63.5 years. The median follow-up was 5.9 months (interquartile range, 2.7-17.0 months) for the entire cohort and 10.6 months (interquartile range, 5.3-40.0 months) for surviving patients. Thirty-one patients (29.8%) had metastatic disease prior to the initiation of RT. Concurrent chemoradiation was administered in 99 patients (95.2%) and 53 patients (51.0%) received trimodal therapy. Systemic therapy included doxorubicin (73.7%), paclitaxel with or without pazopanib (24.3%), and other systemic agents (2.0%). The 1-year OS and LPFS rates were 34.4% and 74.4%, respectively. On multivariate analysis, RT >= 60 Gy was associated with improved LPFS (hazard ratio [HR], 0.135; P = .001) and improved OS (HR, 0.487; P = .004), and trimodal therapy was associated with improved LPFS (HR, 0.060; P = .017). The most commonly observed acute grade 3 adverse events included dermatitis (20%) and mucositis (13%), with no grade 4 subacute or late adverse events noted (adverse events were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.0]). Conclusions RT appears to demonstrate a dose-dependent, persistent LPFS and OS benefit in patients with locally advanced ATC with an acceptable toxicity profile. Aggressive RT should be strongly considered for the treatment of patients with ATC as part of a trimodal treatment approach
Breed-Specific Hematological Phenotypes in the Dog: A Natural Resource for the Genetic Dissection of Hematological Parameters in a Mammalian Species
Remarkably little has been published on hematological phenotypes of the domestic dog, the most polymorphic species on the planet. Information on the signalment and complete blood cell count of all dogs with normal red and white blood cell parameters judged by existing reference intervals was extracted from a veterinary database. Normal hematological profiles were available for 6046 dogs, 5447 of which also had machine platelet concentrations within the reference interval. Seventy-five pure breeds plus a mixed breed control group were represented by 10 or more dogs. All measured parameters except mean corpuscular hemoglobin concentration (MCHC) varied with age. Concentrations of white blood cells (WBCs), neutrophils, monocytes, lymphocytes, eosinophils and platelets, but not red blood cell parameters, all varied with sex. Neutering status had an impact on hemoglobin concentration, mean corpuscular hemoglobin (MCH), MCHC, and concentrations of WBCs, neutrophils, monocytes, lymphocytes and platelets. Principal component analysis of hematological data revealed 37 pure breeds with distinctive phenotypes. Furthermore, all hematological parameters except MCHC showed significant differences between specific individual breeds and the mixed breed group. Twenty-nine breeds had distinctive phenotypes when assessed in this way, of which 19 had already been identified by principal component analysis. Tentative breed-specific reference intervals were generated for breeds with a distinctive phenotype identified by comparative analysis. This study represents the first large-scale analysis of hematological phenotypes in the dog and underlines the important potential of this species in the elucidation of genetic determinants of hematological traits, triangulating phenotype, breed and genetic predisposition
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