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991.

Background

Low rates of adherence to artemisinin-based combination therapy (ACT) regimens increase the risk of treatment failure and may lead to drug resistance, threatening the sustainability of current anti-malarial efforts. We assessed the impact of text message reminders on adherence to ACT regimens.

Methods

Health workers at hospitals, clinics, pharmacies, and other stationary ACT distributors in Tamale, Ghana provided flyers advertising free mobile health information to individuals receiving malaria treatment. The messaging system automatically randomized self-enrolled individuals to the control group or the treatment group with equal probability; those in the treatment group were further randomly assigned to receive a simple text message reminder or the simple reminder plus an additional statement about adherence in 12-hour intervals. The main outcome was self-reported adherence based on follow-up interviews occurring three days after treatment initiation. We estimated the impact of the messages on treatment completion using logistic regression.

Results

1140 individuals enrolled in both the study and the text reminder system. Among individuals in the control group, 61.5% took the full course of treatment. The simple text message reminders increased the odds of adherence (adjusted OR 1.45, 95% CI [1.03 to 2.04], p-value 0.028). Receiving an additional message did not result in a significant change in adherence (adjusted OR 0.77, 95% CI [0.50 to 1.20], p-value 0.252).

Conclusion

The results of this study suggest that a simple text message reminder can increase adherence to antimalarial treatment and that additional information included in messages does not have a significant impact on completion of ACT treatment. Further research is needed to develop the most effective text message content and frequency.

Trial Registration

ClinicalTrials.gov NCT01722734  相似文献   
992.

Introduction

Patients with pulmonary hypertension (PH) often present with a variety of physical findings reflecting a volume or pressure overloaded right ventricle (RV). However, there is no consensus regarding the diagnostic utility of the physical examination in PH.

Methods

We conducted a systematic review of publications that evaluated the clinical examination and diagnosis of PH using MEDLINE (1946–2013) and EMBASE (1947–2013). We also prospectively evaluated the diagnostic utility of the physical examination findings. Patients who underwent right cardiac catheterization for any reason were recruited. After informed consent, participants were examined by 6 physicians (3 “specialists” and 3 “generalists”) who were unaware of the results of the patient''s hemodynamics. Each examiner independently assessed patients for the presence of a RV lift, loud P2, jugular venous distension (JVD), tricuspid insufficiency murmur and right-sided 4th heart sound at rest and during a slow inspiration. A global rating (scale of 1–5) of the likelihood that the patient had pulmonary hypertension was provided by each examiner.

Results

31 articles that assessed the physical examination in PH were included in the final analysis. There was heterogeneity amongst the studies and many did not include control data. The sign most associated with PH in the literature was a loud pulmonic component of the second heart sound (P2). In our prospective study physical examination was performed on 52 subjects (25 met criteria for PH; mPAP ≥25 mmHg). The physical sign with the highest likelihood ratio (LR) was a loud P2 on inspiration with a LR +ve 1.9, 95% CrI [1.2, 3.1] when data from all examiners was analyzed together. Results from the specialist examiners had higher diagnostic utility; a loud P2 on inspiration was associated with a positive LR of 3.2, 95% CrI [1.5, 6.2] and a right sided S4 on inspiration had a LR +ve 4.7, 95% CI [1.0, 15.6]. No aspect of the physical exam, could consistently rule out PH (negative LRs 0.7–1.3).

Conclusions

The presence of a loud P2 or audible right-sided 4th heart sound are associated with PH. However the physical examination is unreliable for determining the presence of PH.  相似文献   
993.
Over 4 million infants die each year from infections, many of which are vaccine-preventable. Young infants respond relatively poorly to many infections and vaccines, but the basis of reduced immunity in infants is ill defined. We sought to investigate whether myeloid-derived suppressor cells (MDSC) represent one potential impediment to protective immunity in early life, which may help inform strategies for effective vaccination prior to pathogen exposure. We enrolled healthy neonates and children in the first 2 years of life along with healthy adult controls to examine the frequency and function of MDSC, a cell population able to potently suppress T cell responses. We found that MDSC, which are rarely seen in healthy adults, are present in high numbers in neonates and their frequency rapidly decreases during the first months of life. We determined that these neonatal MDSC are of granulocytic origin (G-MDSC), and suppress both CD4+ and CD8+ T cell proliferative responses in a contact-dependent manner and gamma interferon production. Understanding the role G-MDSC play in infant immunity could improve vaccine responsiveness in newborns and reduce mortality due to early-life infections.  相似文献   
994.
The lysine demethylase Kdm3a (Jhdm2a, Jmjd1a) is required for male fertility, sex determination, and metabolic homeostasis through its nuclear role in chromatin remodeling. Many histone-modifying enzymes have additional nonhistone substrates, as well as nonenzymatic functions, contributing to the full spectrum of events underlying their biological roles. We present two Kdm3a mouse models that exhibit cytoplasmic defects that may account in part for the globozoospermia phenotype reported previously. Electron microscopy revealed abnormal acrosome and manchette and the absence of implantation fossa at the caudal end of the nucleus in mice without Kdm3a demethylase activity, which affected cytoplasmic structures required to elongate the sperm head. We describe an enzymatically active new Kdm3a isoform and show that subcellular distribution, protein levels, and lysine demethylation activity of Kdm3a depended on Hsp90. We show that Kdm3a localizes to cytoplasmic structures of maturing spermatids affected in Kdm3a mutant mice, which in turn display altered fractionation of β-actin and γ-tubulin. Kdm3a is therefore a multifunctional Hsp90 client protein that participates directly in the regulation of cytoskeletal components.  相似文献   
995.
996.
Research on the use of plants and other complementary medicines in Hawai’i drew our attention toMorinda citrifolia (Rubiaceae). Noni, as it is commonly known, is representative of both currently popular medicinal plants in Ha-wai’i and the pharmacopoeias of traditional cultures of this poly ethnic population. It is also prominent among the increasing number of botanicals currently promoted by the “herbal” and “health foods/supplements” industry. Noni is unique in view of the large number of medical indications that characterize claims for its efficacy, the little that is known about its pharmacologic potential compared with other popularly used botanicals, and its rapidly evolving commercial success. This paper explores how the cultural novelty of noni, in conjunction with its equivocal pharmacology, contribute to its explosive market success in contemporary Hawai’i, and worldwide.  相似文献   
997.
In November-December 2007 a widespread seabird mortality event occurred in Monterey Bay, California, USA, coincident with a massive red tide caused by the dinoflagellate Akashiwo sanguinea. Affected birds had a slimy yellow-green material on their feathers, which were saturated with water, and they were severely hypothermic. We determined that foam containing surfactant-like proteins, derived from organic matter of the red tide, coated their feathers and neutralized natural water repellency and insulation. No evidence of exposure to petroleum or other oils or biotoxins were found. This is the first documented case of its kind, but previous similar events may have gone undetected. The frequency and amplitude of red tides have increased in Monterey Bay since 2004, suggesting that impacts on wintering marine birds may continue or increase.  相似文献   
998.
As scientists, we are at least as excited about the open questions—the things we do not know—as the discoveries. Here, we asked 15 experts to describe the most compelling open questions in plant cell biology. These are their questions: How are organelle identity, domains, and boundaries maintained under the continuous flux of vesicle trafficking and membrane remodeling? Is the plant cortical microtubule cytoskeleton a mechanosensory apparatus? How are the cellular pathways of cell wall synthesis, assembly, modification, and integrity sensing linked in plants? Why do plasmodesmata open and close? Is there retrograde signaling from vacuoles to the nucleus? How do root cells accommodate fungal endosymbionts? What is the role of cell edges in plant morphogenesis? How is the cell division site determined? What are the emergent effects of polyploidy on the biology of the cell, and how are any such “rules” conditioned by cell type? Can mechanical forces trigger new cell fates in plants? How does a single differentiated somatic cell reprogram and gain pluripotency? How does polarity develop de-novo in isolated plant cells? What is the spectrum of cellular functions for membraneless organelles and intrinsically disordered proteins? How do plants deal with internal noise? How does order emerge in cells and propagate to organs and organisms from complex dynamical processes? We hope you find the discussions of these questions thought provoking and inspiring.

We asked 15 experts to address what they consider to be the most compelling open questions in plant cell biology and these are their questions.  相似文献   
999.
The production of recombinant membrane proteins for structural and functional studies remains technically challenging due to low levels of expression and the inherent instability of many membrane proteins once solubilized in detergents. A protocol is described that combines ligation independent cloning of membrane proteins as GFP fusions with expression in Escherichia coli detected by GFP fluorescence. This enables the construction and expression screening of multiple membrane protein/variants to identify candidates suitable for further investment of time and effort. The GFP reporter is used in a primary screen of expression by visualizing GFP fluorescence following SDS polyacrylamide gel electrophoresis (SDS-PAGE). Membrane proteins that show both a high expression level with minimum degradation as indicated by the absence of free GFP, are selected for a secondary screen. These constructs are scaled and a total membrane fraction prepared and solubilized in four different detergents. Following ultracentrifugation to remove detergent-insoluble material, lysates are analyzed by fluorescence detection size exclusion chromatography (FSEC). Monitoring the size exclusion profile by GFP fluorescence provides information about the mono-dispersity and integrity of the membrane proteins in different detergents. Protein: detergent combinations that elute with a symmetrical peak with little or no free GFP and minimum aggregation are candidates for subsequent purification. Using the above methodology, the heterologous expression in E. coli of SED (shape, elongation, division, and sporulation) proteins from 47 different species of bacteria was analyzed. These proteins typically have ten transmembrane domains and are essential for cell division. The results show that the production of the SEDs orthologues in E. coli was highly variable with respect to the expression levels and integrity of the GFP fusion proteins. The experiment identified a subset for further investigation.  相似文献   
1000.
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