Invasive nostocalean cyanobacteria (INC) were first reported in tropical regions and are now globally spreading rapidly due to climate change, appearing in temperate regions. INC require continuous monitoring for water resource management because of their high toxin production potential. However, it is difficult to analyze INC under a microscope because of their morphological similarity to nostocalean cyanobacteria such as the genus .
View Article and Find Full Text PDFInt J Environ Res Public Health
May 2021
The geographical range of invasive cyanobacteria with high toxigenic potential is widening because of eutrophication and global warming, thus, monitoring their appearance is necessary for safe water quality control. Most invasive cyanobacteria are nostocalean species, and their accurate identification by classical morphological methods may be problematic. In this study, we developed polymerase chain reaction (PCR) primers to selectively identify five invasive cyanobacterial genera, namely, , , , , and , using genetic markers such as , , , and , and determined the amplification conditions for each pair of primers.
View Article and Find Full Text PDFThe extent and frequency of harmful cyanobacterial blooms are increasing, owing to the climate change caused by global warming, and some harmful filamentous cyanobacteria that were first reported in the tropics are spreading to temperate regions, such as North America, Europe, and Northeast Asia. Although these exotic invasive cyanobacteria have a high toxigenic potential, they are not targeted in management plans in many countries. This study analyzed the occurrence of and potential toxin and off-flavor secondary metabolite production by invasive nostocalean cyanobacteria in the Nakdong River in Korea, which is a temperate region.
View Article and Find Full Text PDFFollowing the construction of eight large weirs in a 200-km section of the Nakdong River, which is a major water source for the region, harmful cyanobacterial blooms have been occurring annually, causing severe problems with water quality. The present study investigated the community structure of harmful cyanobacteria and identified temporal and spatial patterns in harmful cyanobacterial blooms and their dynamic relationships with physicochemical, hydrological, and meteorological variables in the eight weir sections for 6 years from 2013 to 2018. The dominant harmful cyanobacteria in the eight weir sections were Aphanizomenon and Microcystis spp.
View Article and Find Full Text PDFInt J Environ Res Public Health
October 2018
Int J Environ Res Public Health
August 2018
spp. have formed harmful cyanobacterial blooms in the Nakdong River during spring, autumn, and now in winter, and the expansion of blooming period and area, associated with the global warming is predicted. The genus has been described to produce harmful secondary metabolites such as off-flavors and cyanotoxins.
View Article and Find Full Text PDFBackground: Intensive speech therapy improves language function in patients with chronic aphasia, although treatment in the acute phase is more effective than in the chronic phase. Unfortunately, most patients with stroke go untreated due to socioeconomic problems. This study was performed to develop and test a speech therapy-based telerehabilitation program (iAphasia), suitable for use on a mobile device platform, which would expand access to therapy to patients who frequently go untreated.
View Article and Find Full Text PDFBackground: Early identification of patients with stroke-induced aphasia is essential because it is a significant disability affecting daily life and is linked to poor functional outcome after stroke. However, most patients with stroke are unable to undergo aphasia evaluation and detection and therefore remain undiagnosed. The purpose of this study is to develop a valid, reliable mobile aphasia screening test (MAST) for patients in remote locations.
View Article and Find Full Text PDFTo understand the factors controlling algal production in two lakes located on the Han River in South Korea, Lake Cheongpyeong and Lake Paldang, a principal component regression model study was conducted using environmental monitoring and primary productivity data. Although the two lakes were geographically close and located along the same river system, the main factors controlling primary productivity in each lake were different: hydraulic retention time and light conditions predominantly influenced algal productivity in Lake Cheongpyeong, while hydraulic retention time, chlorophyll a-specific productivity, and zooplankton grazing rate were most important in Lake Paldang. This investigation confirmed the utility of principal component regression analysis using environmental monitoring data for predicting complex biological processes such as primary productivity; in addition, the study also increased the understanding of explicit interactions between environmental variables.
View Article and Find Full Text PDFFunctional brain imaging studies have suggested that the superior temporal gyrus (STG) and the middle temporal gyrus (MTG) are involved in phonological and lexical-semantic processing, respectively. However, the precise role of the posterior temporal lobe is not fully understood. To clarify the functional relevance of the left posterior STG and MTG during language processing, we used neuronavigation-guided repetitive transcranial magnetic stimulation (rTMS).
View Article and Find Full Text PDFBackground: Several experimental studies in stroke patients suggest that mirror therapy and various virtual reality programs facilitate motor rehabilitation. However, the underlying mechanisms for these therapeutic effects have not been previously described.
Objectives: We attempted to delineate the changes in corticospinal excitability when individuals were asked to exercise their upper extremity using a real mirror and virtual mirror.
Objective: To delineate the changes in corticospinal excitability when individuals are asked to exercise their hand using observation, motor imagery, voluntary exercise, and exercise with a mirror.
Method: The participants consisted of 30 healthy subjects and 30 stroke patients. In healthy subjects, the amplitudes and latencies of motor evoked potential (MEP) were obtained using seven conditions: (A) rest; (B) imagery; (C) observation and imagery of the hand activity of other individuals; (D) observation and imagery of own ipsilateral hand activity; (E) observation and imagery of the hand activity of another individual with a mirror; (F) observation and imagery of own symmetric ipsilateral hand activity (thumb abduction) with a mirror; and (G) observation and imagery of own asymmetric ipsilateral hand activity (little finger abduction) with a mirror.
Human immunodeficiency virus-1 (HIV-1) associated dementia (HAD) has been attributed to an encephalitis resulting from intense infiltration of monocytes. Evidence suggests that the viral protein Tat, which is released actively from HIV-1 infected cells, can contribute significantly to this process. Therefore, the principal objective of this study was to evaluate the potential molecular basis for the role of extracellular HIV-1 Tat in the induction of monocyte chemotactic protein-1 (MCP-1/CCL2) in the hippocampus, which is primarily linked to cognitive function and most commonly damaged in HAD.
View Article and Find Full Text PDFObjective: Escherichia coli is the most frequently identified microbiological agent in childhood urinary tract infections (UTIs). However, the pathogenic role of this organism in young children remains to be clearly elucidated. So far, no studies have been conducted in which multiplex polymerase chain reaction (PCR) has been applied to determine the association between childhood UTIs and E.
View Article and Find Full Text PDFIn order to obtain greater insight into the relevant genomic expression patterns of Trichinella spiralis, 992 expressed sequence tags (ESTs) were collected from a cDNA library of T. spiralis muscle stage larvae and assembled into 60 clusters and 385 singletons. Of them, 445 (44.
View Article and Find Full Text PDFBackground: Eosinophils are multifunctional leukocytes. Under physiological conditions, they circulate in the blood and through the tissues to serve their functions. In certain inflammatory states, they enter the T-cell areas of lymph nodes (LNs) that drain the inflamed tissue and communicate with T cells in LNs, but the underlying mechanism that regulates their trafficking to LNs is not yet fully explored.
View Article and Find Full Text PDFContext: Kikuchi disease is a self-limiting febrile lymphadenopathy characterized by a patchy area of apoptosis. Kikuchi disease is thought to be caused by a virus, but this has not been clearly demonstrated. Human herpesviruses 6 and 7 (HHV-6 and HHV-7) are lymphotropic viruses that can induce apoptosis in infected lymphocytes.
View Article and Find Full Text PDFIn a previous study, we determined the gene expression profile of both megakaryocytic and non-megakaryocytic lineage cells via serial analysis of gene expression and microarray methods, and demonstrated that Pim-1 was expressed more abundantly in megakaryocytic lineage cells. In this study, we knocked down Pim-1 in K562 cells, as well as in CD34+ cells from cord blood, via RNA interference, in order to analyze the effects of Pim-1 expression on the megakaryocytic differentiation of these cells. We then additionally overexpressed the Pim-1 genes in K562 cells, and conducted a comparison of these effects with those of RNAi cells on the course of megakaryocytic differentiation.
View Article and Find Full Text PDFThe aim of this study was to compare the serum cytokine profiles of Plasmodium vivax malaria patients who presented with and without hepatic dysfunction. This is a retrospective analysis of 74 consecutive cases of P. vivax malaria seen at 3 military hospitals near the Demilitarized Zone in South Korea from 1999 to 2000.
View Article and Find Full Text PDFSerum cytokine profiles in patients with Plasmodium vivax malaria who presented with and without hyperpyrexia were compared by a retrospective review of the medical records of the consecutive patients seen at the military hospitals near the demilitarized zone in the Republic of Korea from April 2000 through October 2001. Of 162 male patients studied, 120 (86.4%) presented with hyperpyrexia (i.
View Article and Find Full Text PDFThrombopoietin (TPO) is widely used for ex vivo expansion of hematopoietic stem cells. Previously, we have reported that TPO induces a characteristic pattern of apoptosis, and the TPO-induced apoptosis is closely associated with megakaryocyte (MK) differentiation. In the present study, several cytokines, flt3-ligand, stem cell factor (SCF), interleukin-3 (IL-3), IL-6, IL-11, leukemia inhibitory factor, G-CSF, and erythropoietin, which are known to affect megakaryocytopoiesis, have been evaluated to elucidate their effects on the TPO-induced apoptosis.
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