• Journal of Sericultural and Entomological Science
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• v.13 no.1
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• pp.17-22
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• 1971

A series of experiments were conducted from 1968 to 1970 to find the transmission effects of the dwarf disease of mulberry tree in connection with inlay grafting and insect vector with the following conclusions: 1. The inlay-grafting of sound scions on diseased roots showed a 30 per cent transmission rate among the successful grafts. The inlay-grafting of diseased scions on sound roots showed a 14 per cent transmission rate among the successful grafts ir the case of scions cut and stored before wintering but no transmission effect in the case of scions prepared after wintering, There were some stocks, among the unsuccesful grasfts of diseased scions upon sound roots, that sprouted out new buds, no transmission effects were found in them, 2. Leafhoppers (Hishimonus disciguttus Walker) collected from areas with no dwarf disease infection were grouped into three plots and let to feed on mulberry tree severely infected by dwarf disease for 7 days, 14 days and 21 days respectively. After these preliminary treatment, the leafhoppers were recollected to be fed on the sound seedling divided into three plots for 10 days, 15 days and 20 days respectively to find the transmission effects. The results are that the 7 day plot showed no transmission effect whereas the 14 day plot showed a 22 per cent disease rate and the 21 day plot 61 per cent rate indicating that the longer the feeding period is the higher the transmission rate.

• Parasites, Hosts and Diseases
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• v.47 no.3
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• pp.269-273
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• 2009

A 57-year old man who was admitted to an emergency room of a tertiary hospital with hemoptysis developed malarial fever 19 days later and then died from severe falciparum malaria 2 days later. He had not traveled outside of Korea for over 30 years. Through intensive interviews and epidemiological surveys, we found that a foreign patient with a recent history of travel to Africa was transferred to the same hospital with severe falciparum malaria. We confirmed through molecular genotyping of the MSP-1 gene that Plasmodium falciparum genotypes of the 2 patients were identical. It is suggested that a breach of standard infection control precautions resulted in this P. falciparum transmission between 2 patients in a hospital environment. This is the first report of a nosocomial transmission of falciparum malaria in Korea.

• Particle and aerosol research
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• v.6 no.2
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• pp.81-90
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• 2010

Several studies have suggested the possibility of airborne transmission of infectious diseases such as tuberculosis, pandemic influenza. because the number of patients increases explosively, if infectious disease had a high basic reproduction number, pharmaceutical interventions such as vaccination, chemoprophylaxis in the early stage of epidemic. Thus, non-pharmaceutical interventions such as mask-wearing, installing air cleaners, school closure are important to control and prevent the infectious diseases. However, the current technology on the mask, air cleaning, ventilation, and etc., seems to be not originated from the understanding of infection via airborne transmission. It is important to estimate the aerodynamic behavior of saliva droplets by coughing or speaking in order to understand the phenomena of airborne infection. In addition, the prediction of transmission of infectious diseases through the air is critical to prevent or minimize the damage of infection. In this review, we reviewed the recent studies on the airborne infection by focusing on the aerodynamic characteristics of saliva droplets and modeling of airborne transmission.

• Korean Journal of Microbiology
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• v.3 no.1
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• pp.1-6
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• 1965

Over a period of 1962-64, a transmission-experiment of witchess' broom of jujube tree by stem-grafting was conducted. When stem-grafting of sound scions upon diseased roots or diseased scions upon sound roots were carried out, disease transmission of high rate was witnessed; 99% in the former and, in the latter, 62% of the stocks which saw union by callussing and had new shoots. Even when the diseased scions by stem-grafting or the diseased buds by budding upon sound stock died away, the transmission rate was 21% in stem-grafting and 14% in budding which seems to show that, when tissues of diseased plants and stocks are kept contacted over a certain period, the disease transmission occurs. And when the recovered scions taken from once diseased tree were grafted upon diseased roots, the transmission rate was 100 % and therefore it is presumed that the immunity could not be acquired even under the assumption of complete recovery from the disease. In stem-grafting of the diseased scions upon sound roots, 98% of the scions which were stored in the cellar, overwintered and grafted in spring was diseased, whereas the disease rate of the scions which were cut and grafted in spring was only 33%. It was particularly noteworthy that 90% of the scions in the former case and only 3% in the latter case were diseased as of June 18th approximately 2 months after the actual grafting and then the latter advanced to 33% with the passage of time. It appears that the pathogen in branches and shoots of the diseased trees standing outdoors become inactivated or diminished during winter. Through its symptom, pathological change in tissue, and easy transmission of the disease via stem-grafting, it seems certain that the pathogen of the witches broom disease in jujube tree is a virus.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1059-1070
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• 2007

Prion diseases, often called transmissible spongiform encephalopathies (TSEs), are infectious diseases that accompany neurological dysfunctions in many mammalian hosts. Prion diseases include Creutzfeldt-Jakob disease (CJD) in humans, bovine spongiform encephalopathy (BSE, "mad cow disease") in cattle, scrapie in sheep, and chronic wasting disease (CWD) in deer and elks. The cause of these fatal diseases is a proteinaceous pathogen termed prion that lacks functional nucleic acids. As demonstrated in the BSE outbreak and its transmission to humans, the onset of disease is not limited to a certain species but can be transmissible from one host species to another. Such a striking nature of prions has generated huge concerns in public health and attracted serious attention in the scientific communities. To date, the potential transmission of prions to humans via foodborne infection and iatrogenic routes has not been alleviated. Rather, the possible transmission of human to human or cervids to human aggravates the terrifying situation across the globe. In this review, basic features about prion diseases including clinical and pathological characteristics, etiology, and transmission of diseases are described. Based on recently accumulated evidences, the molecular and biochemical aspects of prions, with an emphasis on the molecular interactions involved in prion conversion that is critical during prion replication and pathogenesis, are also addressed.

• Korean journal of applied entomology
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• v.3
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• pp.1-5
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• 1964

Symptom of the mosaic disease of black locust which is presently widespread in Korea was observed and transmission of the disease was investigated by means of grafting Since its symptom was typically mosaic and its transmission was easily accomplished, the disease was considered to be caused by a virus. In investigation of transmission by grafting, it was found out that the discase was easily transmitted in both of the following cases, i. e., healthy seedlings grafted with diseased scions and diseased roots with healthy scions. In the healthy seedlings plus diseased scions grafting, some grafted seedlings were purposedly deprived of the diseased scions after, a certain length of time(10∼30 days), while some were left grafted. The former case showed much higher transmission rate than the latter case, but no fluctuation in rate of transmission by the length of contact period(10-30 days) was recognized. And even when the union between stock and diseased scion by callusing was not successful, the transmission was withnesed. On the basis of the symptom, transmission by grafting, and possibility of transmission by sap inoculation(not published yet), it is supposed that the mosaic virus belongs to the group of the black locust mosaic virus that has been reported in southeastern Europe by Atanasoff(1935) and Milinko et al(1961). It is very likely that the witches' broom of black locust recorded by Myung-O Kim et al(1961) in Korea is the mosaic disease.

• The Korean Journal of Physiology and Pharmacology
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• v.9 no.5
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• pp.255-262
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• 2005

Striatum is involved in the control of movement and habitual memory. It receives glutamatergic input from wide area of the cerebral cortex as well as an extensive serotonergic (5-hydroxytryptamine, 5-HT) input from the raphe nuclei. In our study, the effects of 5-HT on synaptic transmission were studied in the rat corticostriatal brain slice using in vitro whole-cell recording technique. 5-HT inhibited the amplitude as well as frequency of spontaneous excitatory postsynaptic currents (sEPSC) significantly, and neither ${\gamma}-aminobutyric$ acid (GABA)A receptor antagonist bicuculline (BIC), nor $N-methyl-_{D}-aspartate$ (NMDA) receptor antagonist, $_{DL}-2-amino-5-phosphonovaleric$ acid (AP-V) could block the effect of 5-HT. In the presence non-NMDA receptor antagonist, 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenxo[f] quinoxaline-7-sulfonamide (NBQX), the inhibitory effect of 5-HT was blocked. We also figured out that 5-HT change the channel kinetics of the sEPSC. There was a significant increase in the rise time during the 5-HT application. Our results suggest that 5-HT has an effect on both pre- and postsynaptic site with decreasing neurotransmitter release probability of glutamate and decreasing the sensitivity to glutamate by increasing the rise time of non-NMDA receptor mediated synaptic transmission in the corticostriatal synapses.

• Journal of Korean Medical classics
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• v.23 no.2
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• pp.157-189
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• 2010

Many chapters of the Hwangjenaegyeong[HN] explain the process of transmission and transmutation of disease. The transmission and transmutation process in the HN can be categorized into one between the viscera and bowels, and another of the external pathogenic gi itself. The process between the viscera and bowels indicates the transport of the pathologic burden between each viscera and bowel. This again is categorized into three types. Interpromoting, intercontrolling and that by Saeng-yang(生陽), Sa-eum(死陰). Next, the transport of the pathogenic gi can be categorized into one moving inwards from the exterior according to personal traits, and that according to the three Eum and three Yang. Although there are numerous types of transmission and transmutation, there are two main criteria in understanding the process. First, whether the process is in accordance with the physiological or natural flow of the body. Interpromoting and three Eum three Yang processes are such examples. To follow the physiological flow of the body means to correspond to either the Heaven and Earth or the original physiology of the human body. Therefore, the disease progresses according to a certain date or season. This indicates a partial malfunction in the circulation of the vital energy, which is relatively easy to recover. In contrast, there are processes that go against the physiological flow, for example, intercontrolling transmission and transmutation. This process focuses on the movement of the pathogenic gi rather than the vital gi. The disease progresses regardless of the flow of the vital energy, and sequential functional damage occurs accordingly. Consequently, as the transmission and transmutation continue, formerly passed organs are left damaged, and the whole process is headed towards death. The second criteria for understanding the process is whether it is cyclic or not. To have a cyclic pattern means that the occurrence of a disease and the time of death is not fixed. Transmission and transmutation processes that have a cyclic pattern mostly follow the physiological flow of the body. As a result, they rarely end in deaths, and the process is centered on vital energy. On the other hand, those with acyclic patterns have a fixed occurrence and death point in the course of the disease. They are mostly unnatural processes, found in fatal acute diseases or consumption diseases.

• Korean Journal of Medicinal Crop Science
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• v.23 no.4
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• pp.284-291
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• 2015

This study was performed to investigate the effects of enhanced light transmission on plant growth, photosynthetic ability, and disease tolerance to leaf blight, anthracnose in ginseng (Panax ginseng C. A. Meyer, Araliacease family) during the early growth stage (April to June). The photosynthetic ratio, stomatal conductance, and stem diameter of plants grown under a shade net with 15% light transmission rate showed an increasing trend compared to the control plants (5% light transmission rate) although the growth of the aerial parts were not influenced significantly. Plant height, stem length, and leaf length of treated plants were not significantly different from those of the control plants. Root parameters, such as root length, diameter, and weight of treated plants increased significantly compared to the control. Yield performance ($187.4kg{\cdot}10a^{-1}$) of treated plants was 55.5% higher than that of the control ($150.4kg{\cdot}10a^{-1}$). Additionally, disease severity scores of treated plants were lower than those of the control plants, revealing higher survival rates. To retain high yield potential and enhance the level of disease tolerance in ginseng, we suggest the increase of light transmission rate during the early growth stage.

• Journal of Veterinary Science
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• v.24 no.2
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• pp.21.1-21.5
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• 2023

Under the current African swine fever (ASF) epidemic situation, a science-based ASF-control strategy is required. An ASF transmission mechanistic model can be used to understand the disease transmission dynamics among susceptible epidemiological units and evaluate the effectiveness of an ASF-control strategy by simulating disease spread results with different control options. The force of infection, which is the probability that a susceptible epidemiological unit becomes infected, could be estimated by applying an ASF transmission mechanistic model. The government needs to plan an ASF-control strategy based on an ASF transmission mechanistic model.