Etiology and clinical characteristics of fever of unknown origin in children: a 15-year experience in a single center

PurposeFever is one of the most common symptoms in children. In previous studies, infectious disease was the most common cause of pediatric fever of unknown origin (FUO). The aim of this study is to investigate the etiology, clinical characteristics and prognosis of pediatric FUO in 21 century with more diagnostics available and to analyze the factors for certain disease categories.MethodsAmong the children under 18 years old who were hospitalized at Samsung Medical Center from January 2000 to December 2014, the patients who met the criteria including fever of ≥38.0℃ for longer than ≥14 days and failure to reach a diagnosis after one week of investigations were included.ResultsTotal 100 patients were identified. Confirmed diagnosis was achieved in 57 patients (57%). Among them, infectious diseases (n=19, 19%) were most common, followed by connective tissue diseases (n=15, 15%), necrotizing lymphadenitis (n=8, 8%), and malignancies (n=7, 7%). Children with fever duration over 28 days had a trend for higher frequency of connective tissue diseases (28.3%) except undiagnosed etiology. The symptoms such as arthritis, lymph node enlargement and only fever without other symptoms were significantly related with connective tissue diseases, necrotizing lymphadenitis and undiagnosed respectively (P<0.001). Ninety-two patients have become afebrile at discharge and 1 patient died (1%).ConclusionAlmost half of our patients were left without diagnosis. Although it has been known that infectious disease was most common cause of pediatric FUO in the past, undiagnosed portion of FUO have now increased due to development of diagnostic techniques for infectious diseases

Nanoscale Perovskite‐Sensitized Solar Cell Revisited: Dye‐Cell or Perovskite‐Cell?

A general and straightforward way of preparing few nanometer-sized well-separated MAPbIxBr3-x perovskite photosensitizers on the surface of ~1 μm thick mesoporous TiO2 photoanode was suggested via a two-step sequential deposition of low-concentrated lead halides (0.10 ~ 0.30 M PbI2 or PbBr2) and methylammonium iodide/bromide (MAI/MABr). When those nanoscale MAPbIxBr3-x perovskites are incorporated as a photosensitizer in typical solid state dye-sensitized solar cells (ss-DSSCs), it could be verified clearly by the capacitance analysis that nano-particulate MAPbI3 perovskites are playing the same role as that of a typical dye sensitizer (MK-2 molecule) though their size, composition and structure are different

Uric acid regulates α-synuclein transmission in Parkinsonian models

Ample evidence demonstrates that α-synuclein (α-syn) has a critical role in the pathogenesis of Parkinson’s disease (PD) with evidence indicating that its propagation from one area of the brain to others may be the primary mechanism for disease progression. Uric acid (UA), a natural antioxidant, has been proposed as a potential disease modifying candidate in PD. In the present study, we investigated whether UA treatment modulates cell-to-cell transmission of extracellular α-syn and protects dopaminergic neurons in the α-syn-enriched model. In a cellular model, UA treatment decreased internalized cytosolic α-syn levels and neuron-to-neuron transmission of α-syn in donor-acceptor cell models by modulating dynamin-mediated and clathrin-mediated endocytosis. Moreover, UA elevation in α-syn-inoculated mice inhibited propagation of extracellular α-syn which decreased expression of phosphorylated α-syn in the dopaminergic neurons of the substantia nigra leading to their increased survival. UA treatment did not lead to change in markers related with autophagolysosomal and microglial activity under the same experimental conditions. These findings suggest UA may control the pathological conditions of PD via additive mechanisms which modulate the propagation of α-syn

Analytical approach to bit-string models of language evolution

A formulation of bit-string models of language evolution, based on differential equations for the population speaking each language, is introduced and preliminarily studied. Connections with replicator dynamics and diffusion processes are pointed out. The stability of the dominance state, where most of the population speaks a single language, is analyzed within a mean-field-like approximation, while the homogeneous state, where the population is evenly distributed among languages, can be exactly studied. This analysis discloses the existence of a bistability region, where dominance coexists with homogeneity as possible asymptotic states. Numerical resolution of the differential system validates these findings.Comment: To appear in Int. J. Mod. Phys.

The Case of Anticipating Changes in the North Korean Food Safety Regime

40 pagesThis Article aims to provide one of the world’s first analyses of the North Korean food safety regime. Very rarely has this regime been a subject of discussion, as much attention has been diverted to food security issues. However, food safety remains a critical problem for the people

Implementation of Biomimicry for Detecting Composite Structure Damage Using Impedance-Based Non-Destructive Testing Method

Up to date, biomimicry has aided in designing novel ideas and solving various problems in the field of civil engineering. For example, the concept of a load carrying process from a tree can be used to design an effective bridge. Inspired by nature, the authors have adopted the concept of how spiders use vibrations to monitor the state of the web and the presence of prey. A nondestructive testing method known as the electromechanical impedance technique has been proven to be effective when detecting local damage. However, the aforementioned technique uses a high frequency which results in a limited sensing range. Thus, to overcome this problem, an idea using the piezoelectric transducer combined with wires was introduced and tested against composite plates subjected to debonding damage. From the experiment results, the concept introduced from this research shows that biomimicry can increase the sensing range for electromechanical impedance technique which may allow one to create a monitoring system with minimal cost

Characterization of the complete mitogenome of the estuarine benthic ribbon worm Yininemertes pratensis (Sun and Lu 1998) (Nemertea: Lineidae)

The complete mitogenome of the estuarine ribbon worm Yininemertes pratensis (Sun and Lu ) (Nemertea: Lineidae) was sequenced for the first time in the present study. The total length of the newly sequenced mitogenome is 15,616 bp, and it includes 13 protein-coding, 2 rRNA, and 24 tRNA genes, in addition to a noncoding region of 571 bp. The phylogenetic position of Y. pratensis was examined through maximum-likelihood analysis using a concatenated dataset of 13 protein-coding genes from seven selected nemertean species. Yininemertes pratensis is placed within the pilidiophoran group and is closely related to Lineus alborostratus among the selected nemerteans. The newly determined mitogenome sequence will further our knowledge for future phylogenetic and ecological studies of this species