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1.
J Korean Soc Radiol ; 85(3): 581-595, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38873384

RESUMEN

Purpose: The present study aimed to investigate the frequency and extent of compensatory common bile duct (CBD) dilatation after cholecystectomy, assess the time between cholecystectomy and CBD dilatation, and identify potentially useful CT findings suggestive of obstructive CBD dilatation. Materials and Methods: This retrospective study included 121 patients without biliary obstruction who underwent multiple CT scans before and after cholecystectomy at a single center between 2009 and 2011. The maximum short-axis diameters of the CBD and intrahepatic duct (IHD) were measured on each CT scan. In addition, the clinical and CT findings of 11 patients who were initially excluded from the study because of CBD stones or periampullary tumors were examined to identify distinguishing features between obstructive and non-obstructive CBD dilatation after cholecystectomy. Results: The mean (standard deviation) short-axis maximum CBD diameter of 121 patients was 5.6 (± 1.9) mm in the axial plane before cholecystectomy but increased to 7.9 (± 2.6) mm after cholecystectomy (p < 0.001). Of the 106 patients with a pre-cholecystectomy axial CBD diameter of < 8 mm, 39 (36.8%) showed CBD dilatation of ≥ 8 mm after cholecystectomy. Six of the 17 patients with longterm (> 2 years) serial follow-up CT scans (35.3%) eventually showed a significant (> 1.5-fold) increase in the axial CBD diameter, all within two years after cholecystectomy. Of the 121 patients without obstruction or related symptoms, only one patient (0.1%) showed IHD dilatation > 3 mm after cholecystectomy. In contrast, all 11 patients with CBD obstruction had abdominal pain and abnormal laboratory indices, and 81.8% (9/11) had significant dilatation of the IHD and CBD. Conclusion: Compensatory non-obstructive CBD dilatation commonly occurs after cholecystectomy to a similar extent as obstructive dilatation. However, the presence of relevant symptoms, significant IHD dilatation, or further CBD dilatation 2-3 years after cholecystectomy should raise suspicion of CBD obstruction.

2.
Neuroradiol J ; 36(1): 49-58, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35532193

RESUMEN

PURPOSE: Molecular marker status is clinically relevant for treatment planning and predicting the prognosis of gliomas. This study aimed to assess whether quantitative imaging parameters from dynamic susceptibility contrast- (DSC-) and dynamic contrast-enhanced (DCE)-magnetic resonance imaging (MRI) can predict the molecular marker status of lower-grade gliomas (LGGs). MATERIALS AND METHODS: Overall, 132 patients with LGGs who underwent DSC- and DCE-MRI were retrospectively enrolled. Statuses of relevant molecular markers including isocitrate dehydrogenase isoenzyme (IDH), 1p19q codeletion, epidermal growth factor receptor (EGFR), O6-methylguanine-DNA methyltransferase (MGMT), and telomerase reverse transcriptase (TERT) were collected. For each molecular marker, age, tumor diameter and location, and DSC- and DCE-MRI parameters, including the normalized cerebral blood volume (nCBV), volume transfer constant (Ktrans), rate transfer coefficient (Kep), extravascular extracellular volume fraction (Ve), and plasma volume fraction (Vp), were compared. Multivariable logistic regression analyses were performed. RESULTS: The nCBV was significantly lower in LGGs with IDH mutation (p = .001) and TERT mutation (p = .027) than those without these mutations. Ktrans (p = .034), Ve (p = .023), and Vp (p = .044) values were significantly lower in MGMT methylated LGGs than in MGMT unmethylated LGGs. Perfusion parameters were not significantly associated with EGFR amplification and 1p19q codeletion. Young age (p < .001) and small diameter (p = .001) were significantly associated with IDH mutation. The nCBV was independently associated with IDH status (AUC, 0.817; 95% CI: 0.739-0.894). CONCLUSIONS: DSC- and DCE-MRI parameters demonstrated correlations with molecular markers of LGGs. Especially, the nCBV can be helpful in predicting the IDH mutation status.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Estudios Retrospectivos , Neoplasias Encefálicas/patología , Glioma/patología , Imagen por Resonancia Magnética/métodos , Clasificación del Tumor , Isocitrato Deshidrogenasa/genética , Mutación , Medios de Contraste
3.
Artículo en Inglés | MEDLINE | ID: mdl-36078697

RESUMEN

Education using humanoid robots can have a positive impact in many fields, including in medical or physical training. This study investigated the effects of robot interactions with respect to facial expressions, gestures, voices and their combinations on the education of the elderly regarding information and communications technology (ICT) from functional and emotional perspectives. In this study, the robot's interaction methods were divided into four categories: (1) voice, (2) voice and expression, (3) voice and gesture, and (4) voice and expression and gesture. An experiment involving an educational application with a humanoid robot was conducted with a total of 15 elderly people over the age of 60. The effect of the humanoid robot's interaction method on education was identified by means of subjective survey evaluation and practice performance data analysis, including error rate, task success rate, and number of retrainings. Through the experiment, functional and emotional aspects of effects were measured. The results showed that performance and perceived effectiveness were not significantly affected by the type of robot interaction, but the degree to which the robot felt like it had emotions, the degree to which the robot felt like a human, and the degree to which the robot was friendly were significantly different according to the interaction type employed by the humanoid robot. The best effect was achieved when voice and gesture were used together during tutoring. Recognizing that ICT education using humanoid robots increases interest and participation in education, such robots are concluded to be a suitable method for performing ICT education. In addition, when designing robotic interactions, the use of the robot's voice and gestures together is expected to lead to greater anthropomorphism, resulting in a stronger relationship with humanoid robots.


Asunto(s)
Robótica , Anciano , Emociones , Expresión Facial , Humanos , Robótica/métodos
4.
Nurse Educ Today ; 103: 104951, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34015679

RESUMEN

BACKGROUND: Conflict among nurses within the healthcare system negatively impacts them and patient outcomes. Therefore, it is essential to prepare nursing students for conflict resolution in clinical practice. OBJECTIVES: This study aimed to develop a conflict resolution training program based on the situated learning theory (SLT) for nursing students and to verify the impact of the program on abilities of communication, problem-solving, and conflict resolution. DESIGN: This quasi-experimental study was conducted using a non-randomized control group pretest and posttest design. SETTINGS: A college of nursing with the main campus in South Korea. PARTICIPANTS: The subjects were 48 senior nursing students in the last semester of their nursing program. METHODS: The program was developed based on the SLT. It was delivered to the experimental group (90 min per session, a total of eight sessions) while the control group received no intervention. Data were analyzed with χ2-test, Fisher's exact test, unpaired t-test, Mann-Whitney U test, repeated-measures ANOVA, and Bonferroni correction using SPSS/WIN 25.0 program. RESULTS: There were significant interactions between group and time in problem-solving ability (p = 0.048) and subjective conflict resolution ability (p = 0.005). Problem-solving ability and subjective conflict resolution ability in the experimental group significantly improved compared to the control group based on post-hoc test. After the program, objective conflict resolution ability was significantly higher in the experimental group than the control group (p < 0.001). For communication ability, there was a significant interaction between group and time (p = 0.046). However, it showed no significant difference between the two groups in a post-hoc test. CONCLUSIONS: The conflict resolution training program based on the SLT was found to be effective in improving the abilities of problem-solving and conflict resolution of nursing students.


Asunto(s)
Bachillerato en Enfermería , Estudiantes de Enfermería , Humanos , Negociación , Aprendizaje Basado en Problemas , República de Corea
5.
Front Public Health ; 8: 559851, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33178658

RESUMEN

Health professionals contribute toward addressing the sexual health care (SHC) of cancer patients, given the frequency of contact with their patients. This study investigated nurses' and physicians' SHC attitudes, practices, and educational needs relating to cancer patients' SHC. Using a cross-sectional study design, we assessed South Korean health professionals' attitudes, practice, and training needs related to cancer patients' SHC. Differences in attitudes and practices among the groups were analyzed via an independent-samples t-test, ANOVA, and ANCOVA using SPSS. The demographic characteristics, including sex, marital status, and age, were associated with SHC attitudes and practices. There was a significant difference in the level of nurses' and physicians' attitudes regarding SHC. Compared to nurses, physicians were found to hold a more positive attitude toward SHC. Nurses performed practices pertaining to reproductive care significantly more than physicians after controlling for demographic variables. A small correlation was found between scores on the SHCS-A and the SHCS-P among the groups. Participants' educational needs regarding SHC included changes in sexual function, safe sex during treatment, reproductive health, and sexual counseling approaches. Equipping oncology nurses and physicians with the knowledge to extend their roles by managing cancer patients' sexual function, psychological and social problems, and reproductive care would be effective. Additionally, oncology nurses who are mainly women and relatively younger than physicians ought to enhance their skills in communicating with and counseling male cancer patients.


Asunto(s)
Salud Sexual , Actitud del Personal de Salud , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud , Humanos , Masculino
6.
J Am Soc Mass Spectrom ; 28(9): 1987-1990, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28695531

RESUMEN

In matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF), matrix-derived ions are routinely deflected away to avoid problems with ion detection. This, however, limits the use of a quantification method that utilizes the analyte-to-matrix ion abundance ratio. In this work, we will show that it is possible to measure this ratio by a minor instrumental modification of a simple form of MALDI-TOF. This involves detector gain switching. Graphical Abstract ᅟ.

7.
Nurs Ethics ; 24(6): 644-652, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26811393

RESUMEN

BACKGROUND: While nursing ethics education is commonly provided for undergraduate nursing students in most nursing colleges, consensus on the content and teaching modules for these ethics courses have still not been established. OBJECTIVES: This study aimed to examine the effects of nursing ethics education on the moral sensitivity and critical thinking disposition of nursing students in Korea. RESEARCH DESIGN: A one-group pre- and post-test design was used. Moral sensitivity was measured using the Korean version of the Moral Sensitivity Questionnaire. Critical thinking disposition was measured using the Critical Thinking Disposition Questionnaire. Participants and research context: Participants were 70 undergraduate nursing students who were attending a university located in Seoul, Korea. The nursing ethics education was provided 7 times, from September to December 2010, and comprised 90-min sessions each week. Ethical considerations: This study was conducted in accordance with the Human Subject Research Ethics Committee guidelines. FINDINGS: After the education, the levels for the patient-oriented care, a sub-domain of moral sensitivity, and inquisitiveness, a sub-domain of critical thinking disposition, significantly improved. There were no changes in overall scores for moral sensitivity and critical thinking disposition. There were significant positive correlations between moral sensitivity and critical thinking disposition both pre- and post-intervention. CONCLUSION: These results reflect the need for ongoing efforts to develop innovative content, structure, and instructional methods for undergraduate nursing ethics education programs.


Asunto(s)
Ética en Enfermería/educación , Principios Morales , Estudiantes de Enfermería/psicología , Pensamiento , Adulto , Bachillerato en Enfermería/métodos , Femenino , Humanos , Psicometría/instrumentación , Psicometría/métodos , República de Corea , Estudiantes de Enfermería/estadística & datos numéricos , Encuestas y Cuestionarios , Universidades/organización & administración
8.
J Am Soc Mass Spectrom ; 27(11): 1887-1890, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27644944

RESUMEN

The utility of sodium ion adducts produced by matrix-assisted laser desorption ionization for the quantification of analytes with multiple oxygen atoms was evaluated. Uses of homogeneous solid samples and temperature control allowed the acquisition of reproducible spectra. The method resulted in a direct proportionality between the ion abundance ratio I([A + Na]+)/I([M + Na]+) and the analyte concentration, which could be used as a calibration curve. This was demonstrated for carbohydrates, glycans, and polyether diols with dynamic range exceeding three orders of magnitude. Graphical Abstract ᅟ.

9.
J Korean Acad Nurs ; 46(1): 100-8, 2016 Feb.
Artículo en Coreano | MEDLINE | ID: mdl-26963419

RESUMEN

PURPOSE: The aim of this study was to examine the mediating effect of empowerment in the relationship of nurse managers' authentic leadership, with nurses' organizational commitment and job satisfaction. METHODS: The participants in this study were 273 registered nurses working in five University hospitals located in Seoul and Gyeonggi Province. The measurements included the Authentic Leadership Questionnaire, Condition of Work Effectiveness Questionnaire-II, Organizational Commitment Questionnaire and Korea-Minnesota Satisfaction Questionnaire. Data were analyzed using t-test, ANOVA, Scheffé test, Pearson correlation coefficients, simple and multiple regression techniques with the SPSS 18.0 program. Mediation analysis was performed according to the Baron and Kenny method and Sobel test. RESULTS: There were significant correlations among authentic leadership, empowerment, organizational commitment and job satisfaction. Empowerment showed perfect mediating effects in the relationship between authentic leadership and organizational commitment. It had partial mediating effects in the relationship between authentic leadership and job satisfaction. CONCLUSION: In this study, nurse managers' authentic leadership had significant influences on nurses organizational commitment and job satisfaction via empowerment. Therefore, to enhance nurses' organizational commitment and job satisfaction, it is necessary to build effective strategies to enhance nurse manager's authentic leadership and to develop empowering education programs for nurses.


Asunto(s)
Satisfacción en el Trabajo , Liderazgo , Personal de Enfermería en Hospital/psicología , Poder Psicológico , Adulto , Actitud del Personal de Salud , Hospitales Universitarios , Humanos , Enfermeras Administradoras/psicología , Cultura Organizacional , Encuestas y Cuestionarios , Adulto Joven
10.
Rapid Commun Mass Spectrom ; 29(8): 745-52, 2015 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-26406489

RESUMEN

RATIONALE: In our previous analysis of the matrix-assisted laser desorption/ionization (MALDI) spectra of peptides, we treated their depth profiles in solid samples as homogeneous. Here, we wanted to determine if the reproducible MALDI spectra and linear calibration curves reported previously would be obtained even when the depth profiles were inhomogeneous. METHODS: We derived a formula relating shot-number-dependent ion abundance data in temperature-controlled MALDI with the analyte depth profile in a solid sample. We prepared samples containing peptides, amino acids, and serotonin in α-cyano-4-hydroxycinnamic acid matrix by vacuum-drying and micro-spotting methods, recorded their MALDI spectra, and analyzed them with the aforementioned formula. RESULTS: For the samples prepared by vacuum-drying, the analyte depth profiles were inhomogeneous and maximized at the sample surface. Although the MALDI spectra changed as the shot continued, their sum over the entire set of spectra acquired from a spot was reproducible. Similarly, a high-quality calibration curve could be obtained with the spectral data summed over the entire set. Depth profiles were homogeneous for samples prepared by micro-spotting. CONCLUSIONS: A method has been developed to obtain a reproducible MALDI spectrum and a linear calibration curve for an analyte with an inhomogeneous depth profile in a solid sample.


Asunto(s)
Aminoácidos/análisis , Péptidos/análisis , Serotonina/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Ácidos Cumáricos/química , Reproducibilidad de los Resultados
11.
J Am Soc Mass Spectrom ; 26(10): 1657-64, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26122519

RESUMEN

Sample inhomogeneity is one of the obstacles preventing the generation of reproducible mass spectra by MALDI and to their use for the purpose of analyte quantification. As a potential solution to this problem, we investigated MALDI with some liquid matrixes prepared by nonstoichiometric mixing of acids and bases. Out of 27 combinations of acids and bases, liquid matrixes could be produced from seven. When the overall spectral features were considered, two liquid matrixes using α-cyano-4-hydroxycinnamic acid as the acid and 3-aminoquinoline and N,N-diethylaniline as bases were the best choices. In our previous study of MALDI with solid matrixes, we found that three requirements had to be met for the generation of reproducible spectra and for analyte quantification: (1) controlling the temperature by fixing the total ion count, (2) plotting the analyte-to-matrix ion ratio versus the analyte concentration as the calibration curve, and (3) keeping the matrix suppression below a critical value. We found that the same requirements had to be met in MALDI with liquid matrixes as well. In particular, although the liquid matrixes tested here were homogeneous, they failed to display spot-to-spot spectral reproducibility unless the first requirement above was met. We also found that analyte-derived ions could not be produced efficiently by MALDI with the above liquid matrixes unless the analyte was sufficiently basic. In this sense, MALDI processes with solid and liquid matrixes should be regarded as complementary techniques rather than as competing ones.


Asunto(s)
Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/normas , Aminoquinolinas , Compuestos de Anilina , Calibración , Ácidos Cumáricos , Modelos Químicos , Reproducibilidad de los Resultados
12.
J Mass Spectrom ; 50(3): 596-602, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25800197

RESUMEN

Previously, we reported that the matrix-assisted laser desorption ionization spectrum of a peptide became reproducible when an effective temperature was held constant. Using a calibration curve drawn by plotting the peptide-to-matrix ion abundance ratio versus the peptide concentration in a solid sample, a peptide could be quantified without the use of any internal standard. In this work, we quantified proteins by quantifying their tryptic peptides with the aforementioned method. We modified the digestion process; e.g. disulfide bonds were not cleaved, so that hardly any reagent other than trypsin remained after the digestion process. This allowed the preparation of a sample by the direct mixing of a digestion mixture with a matrix solution. We also observed that the efficiency of the matrix-to-peptide proton transfer, as measured by its reaction quotient, was similar for peptides with arginine at the C-terminus. With the reaction quotient averaged over many such peptides, we could rapidly quantify proteins. Most importantly, no peptide standard, not to mention its isotopically labeled analog, was needed in this method.


Asunto(s)
Fragmentos de Péptidos/análisis , Proteínas/análisis , Animales , Bovinos , Humanos , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Proteínas/química , Proteínas/metabolismo , Análisis de Secuencia de Proteína , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Tripsina/metabolismo
13.
J Am Soc Mass Spectrom ; 25(8): 1502-5, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24845358

RESUMEN

Previously, we reported that MALDI spectra of peptides became reproducible when temperature was kept constant. Linear calibration curves derived from such spectral data could be used for quantification. Homogeneity of samples was one of the requirements. Among the three popular matrices used in peptide MALDI [i.e., α-cyano-4-hydroxycinnamic acid (CHCA), 2,5-dihydroxybenzoic acid (DHB), and sinapinic acid (SA)], homogeneous samples could be prepared by conventional means only for CHCA. In this work, we showed that sample preparation by micro-spotting improved the homogeneity for all three cases.


Asunto(s)
Métodos Analíticos de la Preparación de la Muestra , Oligopéptidos/análisis , Calibración , Ácidos Cumáricos/química , Técnicas Electroquímicas , Gentisatos/química , Límite de Detección , Membranas Artificiales , Microquímica/métodos , Peso Molecular , Oligopéptidos/química , Reproducibilidad de los Resultados , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Propiedades de Superficie
14.
Int J Nurs Pract ; 20(5): 482-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24112319

RESUMEN

This study aimed to examine the level of moral sensitivity and critical thinking disposition among baccalaureate nursing students in Korea. A convenience sample of 142 undergraduate nursing students was surveyed on moral sensitivity using the Korean version of the Moral Sensitivity Questionnaire (K-MSQ) and on critical thinking disposition using the Critical Thinking Disposition Questionnaire (CTDQ). Data were collected from June 2009 to July 2010. Mean score was 2.83 out of 7 on the K-MSQ (relatively low) and 3.70 out of 5 on the CTDQ (relatively high), indicating the need for nursing educators to continue to develop and incorporate strategies that enhance moral sensitivity into ethics courses in undergraduate nursing programs in Korea. Nursing students who regarded nursing as a lifelong career exhibited stronger critical thinking disposition than did students who considered nursing to be a temporary or premarital job. Moral sensitivity should be further emphasized in nursing ethics courses in undergraduate nursing programs in Korea.


Asunto(s)
Principios Morales , Estudiantes de Enfermería/psicología , Pensamiento , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea , Encuestas y Cuestionarios , Adulto Joven
15.
Anal Chem ; 85(18): 8796-801, 2013 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-23971407

RESUMEN

We propose to divide matrix suppression in matrix-assisted laser desorption ionization into two parts, normal and anomalous. In quantification of peptides, the normal effect can be accounted for by constructing the calibration curve in the form of peptide-to-matrix ion abundance ratio versus concentration. The anomalous effect forbids reliable quantification and is noticeable when matrix suppression is larger than 70%. With this 70% rule, matrix suppression becomes a guideline for reliable quantification, rather than a nuisance. A peptide in a complex mixture can be quantified even in the presence of large amounts of contaminants, as long as matrix suppression is below 70%. The theoretical basis for the quantification method using a peptide as an internal standard is presented together with its weaknesses. A systematic method to improve quantification of high concentration analytes has also been developed.


Asunto(s)
Péptidos/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/normas , Calibración/normas
16.
J Am Soc Mass Spectrom ; 24(6): 868-76, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23595259

RESUMEN

In our previous matrix-assisted laser desorption ionization (MALDI) studies of peptides, we found that their mass spectra were virtually determined by the effective temperature in the early matrix plume, Tearly, when samples were rather homogeneous. This empirical rule allowed acquisition of quantitatively reproducible spectra. A difficulty in utilizing this rule was the complicated spectral treatment needed to get Tearly. In this work, we found another empirical rule that the total number of particles hitting the detector, or TIC, was a good measure of the spectral temperature and, hence, selection of spectra with the same TIC resulted in reproducible spectra. We also succeeded in obtaining reproducible spectra throughout a measurement by controlling TIC near a preset value through feedback adjustment of laser pulse energy. Both TIC selection and TIC control substantially reduced the shot-to-shot spectral variation in a spot, spot-to-spot variation in a sample, and even sample-to-sample variation in MALDI using α-cyano-4-hydroxycinnamic acid or 2,5-dihydroxybenzoic acid as matrix. Based on the utilization of acquired data, TIC control was more efficient than TIC selection by an order of magnitude. Both techniques produced calibration curves with excellent linearity, suggesting their utility in quantification of peptides.


Asunto(s)
Péptidos/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Calibración , Ácidos Cumáricos/química , Gentisatos/química , Iones/análisis , Iones/química , Péptidos/análisis , Reproducibilidad de los Resultados , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/instrumentación , Temperatura
17.
J Mass Spectrom ; 48(3): 299-305, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23494784

RESUMEN

In a previous study on matrix-assisted laser desorption ionization (MALDI) of peptides using α-cyano-4-hydroxycinnamic acid (CHCA) as a matrix, we found that the patterns of single-shot spectra obtained under different experimental conditions became similar upon temperature selection. In this paper, we report that absolute ion abundances are also similar in temperature-selected MALDI spectra, even when laser fluence is varied. The result that has been obtained using CHCA and 2,5-dihydroxybenzoic acid as matrices is in disagreement with the hypothesis of laser-induced ionization of matrix as the mechanism for primary ion formation in MALDI. We also report that the total number of ions in such a spectrum is unaffected by the identity, concentration and number of analytes, i.e. it is the same as that in the spectrum of pure matrix. We propose that the generation of gas-phase ions in MALDI can be explained in terms of two thermal reactions, i.e. the autoprotolysis of matrix molecules and the matrix-to-analyte proton transfer, both of which are in quasi-equilibrium in the early matrix plume.


Asunto(s)
Péptidos/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Ácidos Cumáricos/química , Gases/química , Gentisatos/química , Iones/química , Reproducibilidad de los Resultados , Temperatura
18.
Anal Chem ; 84(23): 10332-7, 2012 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-23145820

RESUMEN

Even though matrix-assisted laser desorption ionization (MALDI) is a powerful technique for mass spectrometry of peptides and proteins, it is not quite useful for their quantification that is one of the outstanding problems in quantitative proteomics. The main difficulty lies in the poor reproducibility of MALDI spectra. In this work, a simple method to circumvent this problem has been developed. The method is based on a previous observation that the reaction quotient for the matrix-to-peptide proton transfer evaluated in temperature-selected MALDI was nearly constant regardless of the peptide concentration in the solid sample. This implied a direct proportionality between the relative abundance of an analyte ion in a temperature-selected MALDI spectrum and the concentration of the corresponding neutral in the solid sample. This relation has been confirmed by calibration curves obtained for some peptides. Another characteristic of the relation is that it holds even when other analytes are present. This has been demonstrated for mixtures containing peptides and proteins. This and the fact that the method does not require the addition of internal standards allow rapid and inexpensive quantification of any analyte amenable to MALDI.


Asunto(s)
Fragmentos de Péptidos/análisis , Proteínas/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Cromatografía Liquida , Humanos , Proteómica
19.
J Korean Acad Nurs ; 42(1): 28-35, 2012 Feb.
Artículo en Coreano | MEDLINE | ID: mdl-22410599

RESUMEN

PURPOSE: This study was done to evaluate the effects of a short-term life review on spiritual well-being, depression, and anxiety in patients with terminal cancer. METHODS: The study used a pre posttest quasi experimental design with a nonequivalent control group. Measurement instruments included the Functional Assessment of Chronic Illness Therapy-Spiritual scale (FACIT-Sp12) and the Hospital Anxiety and Depression Scale (HADS). Participants were 32 patients with terminal cancer who were receiving chemotherapy or palliative care at hospitals or at home. Eighteen patients were assigned to the experimental group and 14 to the control group. A sixty minute short-term life review session was held twice a week as the intervention with the experimental group. RESULTS: There was a statistically significant increase in spiritual well-being in the experimental group compared to the control group. There were also significant decreases in depression and anxiety in the experimental group compared to the control group. CONCLUSION: The results indicate that a short-term life review can be used as a nursing intervention for enhancing the spiritual well-being of patients with terminal cancer.


Asunto(s)
Ansiedad , Depresión , Neoplasias/psicología , Espiritualidad , Anciano , Enfermedad Crónica , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Cuidados Paliativos , Enfermo Terminal
20.
J Korean Acad Nurs ; 40(1): 69-77, 2010 Feb.
Artículo en Coreano | MEDLINE | ID: mdl-20220283

RESUMEN

PURPOSE: This methodological research was designed to develop performance evaluation key indicators (PEKIs) for management by objectives (MBO) and to estimate their weights for hospital nurses. METHODS: The PEKIs were developed by selecting preliminary indicators from a literature review, examining content validity and identifying their level of importance. Data were collected from November 14, 2007 to February 18, 2008. Data set for importance of indicators was obtained from 464 nurses and weights of PEKIs domain was from 453 nurses, who worked for at least 2 yr in one of three hospitals. Data were analyzed using X(2)-test, factor analysis, and the Analytical Hierarchy Process. RESULTS: Based upon Content Validity Index of .8 or above, 61 indicators were selected from the 100 preliminary indicators. Finally, 40 PEKIs were developed from the 61 indicators, and categorized into 10 domains. The highest weight of the 10 domains was customer satisfaction, which was followed by patient education, direct nursing care, profit increase, safety management, improvement of nursing quality, completeness of nursing records, enhancing competence of nurses, indirect nursing care, and cost reduction, in that order. CONCLUSION: PEKIs and their weights can be utilized for impartial evaluation and MBO for hospital nurses. Further research to verify PEKIs would lead to successful implementation of MBO.


Asunto(s)
Evaluación del Rendimiento de Empleados , Personal de Enfermería en Hospital/normas , Adulto , Humanos , Modelos de Enfermería , Investigación en Evaluación de Enfermería , Análisis y Desempeño de Tareas
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