The pyrimidine nucleoside uridine has recently been reported to have a protective effect on cultured human corneal epithelial cells, in an animal model of dry eye and in patients. In this study, we investigate the pharmacokinetic profile of uridine in rabbits, following topical ocular (8 mg/eye), oral (450 mg/kg) and intravenous (100 mg/kg) administration. Blood and urine samples were serially taken, and uridine was measured by high-performance liquid chromatography-tandem mass spectrometry. No symptoms were noted in the animals after uridine treatment. Uridine was not detected in either plasma or urine after topical ocular administration, indicating no systemic exposure to uridine with this treatment route. Following a single intravenous dose, the plasma concentration of uridine showed a bi-exponential decay, with a rapid decline over 10 min, followed by a slow decay with a terminal half-life of 0.36 +/- 0.05 h. Clearance and volume of distribution were 1.8 +/- 0.6 L/h/kg and 0.58 +/- 0.32 L/kg, respectively. The area under the plasma concentration-time curves (AUC) was 59.7 +/- 18.2microg.hr/ml, and urinary excretion up to 12 hr was ~7.7% of the dose. Plasma uridine reached a peak of 25.8 +/- 4.1 microg/ml at 2.3 +/- 0.8 hr after oral administration. The AUC was 79.0 +/- 13.9 microg.hr/ml, representing ~29.4% of absolute bioavailability. About 1% of the oral dose was excreted in the urine. These results should prove useful in the design of future clinical and nonclinical studies conducted with uridine.
Administration, Intravenous* ; Administration, Ophthalmic ; Administration, Oral ; Animals ; Area Under Curve ; Biological Availability ; Epithelial Cells ; Half-Life ; Humans ; Mass Spectrometry ; Models, Animal ; Pharmacokinetics* ; Plasma ; Rabbits* ; Uridine*

It has been found that acetylcholine releases at least two different substances from the vascular endothelial cells, i.e., relaxing factor and hyperpolarizing factor. The present study was armed to investigate whether and to what extent these factors are involved in the relaxation of the corpus cavernosum. The corpus cavernosum was isolated from male New Zealand white rabbits and suspended longitudinally in an organ bath. The corporal strips were precontracted with phenylephrine, tetraethylammonium (TEA) or potassium chloride, and their responses to electrical field stimulation (EFS) or exogenously-administered acetylcholine were examined. EFS caused a frequency-dependent relaxation of the corpus cavernosum precontracted with phenylephrine, which was significantly inhibited or abolished in the presence of procaine (3.5 x 0.0001mol/L) or ouabain (0.0001mol/L). The corporal preparation precontracted with TEA also showed a frequency-dependent relaxation, however, the degree of which was lower than that precontracted with phenylephrine. EFS was without a significant effect on the corporal preparation precontracted with KCl (3 x 0.01mol/L). Acethylcholine elicted a concentration-dependent relaxation of the corpus cavernosum, the magnitude of which was significantly diminished in the presence of L-NAME (0.0001 mol/L). The relaxation response to EFS of the corporal preparation precontracted with phenylephrine was significantly attenuated in the presence of L-NAME (0.0001 mol/L), in which the residual relaxation was completely abolished by glibenclamide (0.00001mol/L). The relaxation of the corpus cavernosum in response to EFS was reversed into a contraction by methylene blue (0.0001mol/L) or TEA (0.01mol/L). These results suggest that endothelium-derived relaxing and hyperpolarizing factors released upon neural stimulation mediate the relaxation of the corpus cavernosum. It is also suggested that EDRF activates soluble guanylate cyclase and EDHF does ATP-sensitive potassium channels.
Acetylcholine ; Arm ; Baths ; Endothelial Cells ; Glyburide ; Guanylate Cyclase ; Humans ; KATP Channels ; Male ; Methylene Blue ; NG-Nitroarginine Methyl Ester ; Ouabain ; Phenylephrine ; Potassium Chloride ; Procaine ; Rabbits ; Relaxation* ; Tea ; Tetraethylammonium

PURPOSE: The purpose of this study was to explore the lived experiences of homeless persons. METHODS: A phenomenological methodology was used for the study. Participants were people enrolled in the Center for homeless persons in Kyunggi Province and eligible for the study. Data were collected through in-depth interviews with nine participants between October 13 and November 16, 2016. Data analysis was conducted using Colaizzi's method. RESULTS: Five themes and twenty meanings were formulated for experiences of homeless persons. The five themes were ‘Abandoning their life’, ‘Being familiar with a free homeless life’, ‘Being isolated from the world’, ‘Being impoverished’, ‘Desire to break away from the life of homelessness’. CONCLUSION: The study results suggest the need for a holistic understanding of the essential structure of the lived experiences of homeless persons. Mental health professionals need to understand the homelessness experiences from the client view and to develop programs that can help homeless persons reintegrate into the community.
Gyeonggi-do ; Homeless Persons* ; Humans ; Mental Health ; Methods ; Qualitative Research ; Statistics as Topic

PURPOSE: To propose a conceptual design of a novel source for intensity modulated brachytherapy. MATERIALS AND METHODS: The source design incorporates both radioactive and shielding materials (stainless steel or tungsten), to provide an asymmetric dose intensity in the azimuthal direction. The intensity modulated intravascular brachytherapy was performed by combining a series of dwell positions and times, distributed along the azimuthal coordinates. Two simple designs for the beta-emitting sources, with similar physical dimensions to a 90Sr/Y Novoste Beat-Cath source, were considered in the dosimetric feasibility study. In the first design, the radioactive and materials each occupy half of the cylinder and in the second, the radioactive material occupies only a quater of the cylinder. The radial and azimuthal dose distributions around each source were calculated using the MCNP Monte Carlo code. RESULTS: The preliminary hypothetical simulation and optimization results demonstrated the 87% difference between the maximum and minimum doses to the lumen wall, due to off-centering of the radiation source, could be reduced to less than 7% by optimizing the azimuthal dwell positions and times of the partially shielded intravascular brachytherapy sources. CONCLUSION: The novel brachytherapy source design, and conceptual source delivery system, proposed in this study show promising dosimetric characteristics for the realization of intensity modulated brachytherapy in intravascular treatment. Further development of this concept will center on building a delivery system that can precisely control the angular motion of a radiation source in a small-diameter catheter.
Brachytherapy* ; Catheters ; Feasibility Studies* ; Steel

PURPOSE: The purpose of this study was to investigate factors affecting resilience in nursing students. METHODS: A survey was conducted with 200 nursing students at a college and a university in P city and K city. Data were collected from March 1 to 20, 2017, and analyzed with SPSS PASW 22.0. RESULTS: In the hierarchical analysis, factors affecting resilience were emotional intelligence (β=.39, p<.001), psychological well-being (β=.31, p<.001), and self-esteem (β=.16, p=.010). The variable that had the highest impact was emotional intelligence and the explanation power of the regression model was 65%(F=34.40 p<.001). CONCLUSION: The findings of this study indicate that emotional intelligence, psychological well-being, and self-esteem are essential for resilience in nursing students. Thus, enhancing emotional intelligence and psychological well-being would be an effective strategy to improve resilience in nursing students.
Emotional Intelligence* ; Humans ; Nursing* ; Resilience, Psychological ; Students, Nursing*

PURPOSE: The purpose of this study was to explore the coping process of chief Executive Nurses(CENs) Who Had Experienced Unexpected Dismissal.The research question was "would you tell me about your experience of sudden dismissal?" METHOD: The methodology of collecting and analyzing data used in this study followed the ground theory of Strauss and Corbin (1998). Data were collected through in-depth interviews with open-ended questions about the subjects' coping experiences, which were audio-taped and transcribed. The survey was conducted between April and May, 2007. The subjects of this study were 5 CENs. RESULT: The results of the study are as follows. Core category of This Study was "Battling unsupported against the overwhelming reality." The participants had to face the most unexpected reality of being laid off. Their emotional/psychological response were betrayal, powerlessness, lonesomeness, sorrow, and hopelessness. They felt like a general who is facing overwhelming enemy in a war. The coping process was found to have four stages: shocked stage, resisting stage, negotiating stage and reflecting and transcending stage. CONCLUSION: The result of this study suggested that ceaseless exertion and cooperation at organizational and individual levels are needed to establish stable status and power of nursing departments and CENs in hospitals.
Negotiating ; Shock ; Unemployment

PURPOSE: To date most research related to patients with breast cancer has discriminately investigated the status within or after the treatment although the patients demand holistic nursing care from the time of diagnosis. Thus, the purpose of this study was to investigate the trajectory of breast cancer diagnosis and patients' experiences in the pre-treatment period. METHOD: This qualitative study used qualitative thematic analysis. Nineteen Korean women who were diagnosed with breast cancer within the last 6 month participated in the study. Individualized interviews were conducted with each participant in a cancer center in K city. The interviews were tape-recorded, transcribed, and analyzed using the thematic analysis process. RESULTS: The overriding theme was "the scattered life in an unforeseen swirl", which illustrates the participants' unexpected crisis with confusion and emotional distress. Two subthemes included "falling into an unavoidable journey", and "staggering in a muddle with urgency". The categories were "unexpected probability", "nagging nodularity", "ominous presentiment", "emotional upheaval", "bad thought intrusion", and "a sense of urgency". CONCLUSION: Patients in the pre-treatment period encountered utter emotional distress and a sense of urgency after being diagnosed breast cancer. Strategies to develop nursing care for patients in this period and nursing implications are discussed.
Breast ; Breast Neoplasms ; Female ; Holistic Nursing ; Humans ; Nursing Care ; Qualitative Research

PURPOSE: The purpose of this study was to identify the risk factors for falls among the elderly living in community. METHOD: This was a descriptive study. The subjects comprised 80 elderly aged 65 years or over living in D city. The instruments used for this study was the MDS-HC V2.0. The data was analyzed by SPSS Win 14.0 using t-test, ANOVA, and Pearson correlation. RESULT: Among the socio-demographic characteristics, the significant differences were found in ADL by gender and marital status. Older elderly(> or =85) used more medications than other elderly. The elderly were use average 4.33 medications, but 46.3% of the subjects didn't have the physician reviewed all medications. There was statistically significant correlation between number of medications and accidental falls. CONCLUSION: Nurses should inspect about the number of medications, drug interaction, and side effects. It would be preventive intervention for falls in elderly.
Accidental Falls ; Activities of Daily Living ; Aged ; Drug Interactions ; Humans ; Marital Status ; Obesity ; Risk Factors

PURPOSE: This study was done to analyze core competencies affecting critical thinking ability of student nurses. Core competencies investigated in this study were problem solving ability, communication ability and self-directed learning ability. METHOD: Data were collected from a convenience sample of 322 student nurses in 2 provinces during the period from May 21 to June 8, 2007. Critical thinking, problem solving ability, communication ability and self-directed learning ability were measured using the Disposition towards Critical Thinking Scale by Park (1999-a) and the Core Competencies Scale by Lee (2003). Descriptive statistics and correlation coefficients with the SPSS WIN 12.0 program were used to analyze the data. RESULTS: There were significant differences in the critical thinking according to grade, type of high school, experience with PBL, preference for lecture-based learning, preference for discussion and perceived logicality. The score for critical thinking showed significantly positive correlations with scores for problem solving ability (r=0.54, p=0.00), communication ability (r=0.56, p=0.00) and self-directed learning ability (r=0.54, p=0.00). CONCLUSION: The results of this study suggest that problem solving ability, communication ability and self-directed learning ability are significant factors affecting critical thinking in student nurses.
Communication* ; Humans ; Learning* ; Logic ; Problem Solving ; Thinking*

Menopause is a well-known risk factor for accelerating cognitive aging in women. This study aimed to assess differences in cognitive function and health-related quality of life (HRQOL) according to menopausal status to determine whether the menopause significantly affects the relationship between cognitive function and HRQOL.