Identification of North American Nursing Diagnosis Association-Nursing Interventions Classification-Nursing Outcomes Classification of nursing home residents using on-time data by android smartphone application by registered nurses.

PURPOSE: We aimed to investigate the nursing process linkages formed by Nursing Interventions Classification (NIC) and Nursing Outcomes Classification (NOC) according to the primary NANDA-I diagnoses by registered nurses (RNs), customized to nursing home (NH) residents in Korea, using a developed smartphone application for NH RNs. METHODS: This is a retrospective descriptive study. Applying quota sampling, a total of 51 NHs from all operating 686 NHs hiring RNs participated in this study. Data were collected from June 21 to July 30, 2022. Data on NANDA-I, NIC, NOC (NNN) of nurses applied to the NH residents were collected through a developed smartphone application. The application consists of general organization and residents' characteristics, NANDA-I, NIC, and NOC. RNs selected randomly up to 10 residents and NANDA-I with risk factors and related factors over the past 7 days, followed by all applied interventions out of 82 NIC. RNs then evaluated residents through 79 selected NOC. RESULTS: We found the frequently used NANDA-I diagnoses, Nursing Interventions Classifications and Nursing Outcomes and Classifications applied for NH residents by RNs and developed the top five NOC linkages used to build care plan. CONCLUSION: It is time to pursue high-level evidence and reply to the questions raised in NH practice using NNN with high technology. The outcomes for patients and nursing staff are improved by the continuity of care made possible by uniform language. IMPLICATIONS FOR NURSING PRACTICE: NNN linkages should be used to construct and utilize the coding system of electronic health records or electronic medical records in Korean long-term care facilities.

Assessing objective cognitive impairments in cancer survivors: Features and validity of measures for research and clinical applications.

Objective: This narrative review aims to (1) identify neuropsychological tests for assessing cognitive function impairment in patients with cancer, specifically in the domains of attention and memory, (2) summarize the characteristics of these tests, including cognitive function domains, test content, readability, and psychometric quality, and (3) evaluate the feasibility of each test in cancer care. Methods: Data sources include published test manuals, documents from official web pages, and published journal articles. Results: Our study identified eight neuropsychological tests that are most frequently used to assess the attention and memory domains of objective cognitive function in patients with breast cancer. These tests include the California Verbal Learning Test, Hopkins Verbal Learning Test, Rey Auditory Verbal Learning Test, Rey-Osterrieth Complex Figure, CNS Vital Signs, Wechsler Adult Intelligence Scale, Wechsler Memory Scale, and Trail Making Test. They demonstrate acceptable evidence of psychometric quality and varying degrees of feasibility. Test feasibility is influenced by factors such as short testing time, brevity and comprehensiveness, clear cognitive domain distinctions, availability of normative data, minimal practice effects, ease of administration, and limited attention-span requirements. These attributes determine a test's feasibility for use in cancer care. Among the evaluated measures, the California Verbal Learning Test for memory, the Trail Making Test for attention, and the CNS Vital Signs for comprehensive assessment emerge as the most practical choices for cancer care. Conclusions: The assessment and management of cognitive function impairment are crucial for enhancing the quality of life in cancer survivors. Nurses should possess knowledge of assessment tools for early detection and the ongoing monitoring of this symptom's progression.

Public Perception Before and After COVID-19 Vaccine Pass for the Unvaccinated to Eat Alone: Social Media Data Analytics.

This study was conducted to compare the trends of public perception in South Korea about the vaccine pass requiring the unvaccinated to eat alone during the COVID-19 crisis. Data were collected via Text mining; frequency, association, and sentiment analysis using the social big data analysis service, (known as "Some-Trend"), 2 months before and after December 16, 2021, when the vaccine pass was announced. The total number of search results was 4899 occurrences of the keywords using "eating alone" and "Hon-bab" (Korean abbreviation for eating alone). During the week of December 16, the frequency was the highest (770 occurrences). Compared to the weeks before the announcement sentiment analysis shows that words including "Reject," "Discrimination," and "Uncomfortable," among others, either newly appeared or increased in frequency. And also, the percentage of positive words decreased from 54.5% to 34% and that of negative words increased from 30.2% to 43.3%. The introduction of the vaccine pass has raised negative public interest, particularly regarding the policy of unvaccinated people forcefully restricted to eat alone. Accordingly, this study showed that the vaccine policy had not gain positive perception of the public.

Neuropsychological Effects of Chemotherapy: Systematic Review of Longitudinal Studies on Objective Cognitive Impairment in Breast Cancer Patients.

BACKGROUND: Findings from longitudinal studies can provide more conclusive evidence as to the impact of chemotherapy on cognitive functioning. OBJECTIVES: This study aimed to ( a ) synthesize the evidence from longitudinal studies of the neuropsychological effects associated with chemotherapy in breast cancer patients, ( b ) identify associated factors, and ( c ) evaluate methodological issues. METHODS: Data were extracted from PubMed, EMBASE, CINAHL, PsycINFO, and the Cochrane Library. Inclusion criteria included the original study with the breast cancer sample, validated measure, and at least 1 baseline data point before and after chemotherapy began. Data accrued for sample characteristics, data-collection time points, statistical methods for longitudinal data analysis, outcome measures, and major findings (eg, longitudinal changes in cognitive function). RESULTS: We selected 42 articles for this review. The sample sizes ranged from 20 to 610, and most recruited were younger than 70 years. We found a trend across studies-statistically significant objective cognitive function deteriorations in severity and prevalence after initiating chemotherapy compared with a control group or relative to their baseline observations. A subsample, as high as 65%, experienced marked declines in cognitive function after initiating chemotherapy. The memory domain was most affected. The consistently associated factors were education, IQ, and regimen. Major methodological concerns were the measurement-the wide range of neuropsychological tests and a test's unclear domains. CONCLUSION: Chemotherapy affects objective cognitive function in some subsets. The highest-impact time point, mechanisms, and clinical significance of chemotherapy-associated cognitive impairment need additional evidence. IMPLICATION FOR PRACTICE: Clinicians must assess and manage cognitive impairment during and after chemotherapy.

Heuristic smartphone usability evaluations of the mobile application NANDA, nursing interventions classification, and nursing outcomes classification customized for nursing home registered nurses.

PURPOSE: We aimed to evaluate the usability of a smartphone application consisting of standardized nursing language (SNL) using NANDA, Nursing Intervention Classification, and Nursing Outcome Classification for nursing home nurses. DATA SOURCES: Applying convenience sampling, a total of 14 experts and 15 real users were invited to test and evaluate the smartphone application independently. For the usability evaluation of the developed application, the Korean version of the Mobile Application Rating Scale for experts and Mobile Application Rating Scale: User Version developed by Stoyanov et al. were used. DATA SYNTHESIS: Both groups determined that the SNL application was quite informative about SNL and efficient function; however, the engagement was quite lower than other categories. CONCLUSIONS: Although SNLs were scientifically developed for several decades, the widely available technological application for registered nurses in different languages is urgently needed to improve quality of nursing care. IMPLICATIONS FOR NURSING PRACTICE: The identified problems and recommendations by users and experts using heuristic evaluation will be reflected in the application's final version to be used for research.

Infection preventive behaviors and its association with perceived threat and perceived social factors during the COVID-19 pandemic in South Korea: 2020 community health survey.

BACKGROUND: This study examined why some individuals have not properly performed health prevention behavior during the coronavirus disease 2019 (COVID-19) pandemic. We used data from a community health survey conducted by public health centers in South Korea to identify factors affecting COVID-19 prevention behavior in urban and rural areas. Also, we examined whether individual-level demographic, socio-psychological, and structural variables affected COVID-19 prevention behavior by referring to a model explaining individuals' health prevention behavior. In particular, the study is significant as not many other measures were suggested besides compliance with personal quarantine rules during the early phase of the pandemic in 2020. We hope that the results of this study will be considered in further analysis of infection preventive behavior and in future health crises. METHODS: Probability proportional and systematic sampling were used to collect data in 2020 from 229,269 individuals. After exclusion, the valid data from 141,902 adults (86,163 urban and 44,739 rural) were analyzed. We performed t-tests and analyses of variance to ascertain the differences in COVID-19 preventive behaviors according to demographic characteristics, and a post-hoc analysis was conducted using Scheffé's test. Factors that affected participants' COVID-19 preventive behaviors were analyzed using multiple regression analyses. RESULTS: The variables significantly influencing COVID-19 preventive behaviors in urban areas were age, gender, living with two or more people, educational level, monthly household income, working status, influenza vaccination, daily life stress, and perceived threat. In rural areas, age, gender, living with two or more people, education level, influenza vaccination, daily life stress, perceived threat, and perceived social factors were significantly associated with increased COVID-19 preventive behaviors. CONCLUSIONS: Several demographic characteristics were associated with urban and rural residents' COVID-19-related preventive behaviors. A different approach is needed for the two regions in future policy. Future studies should aim to improve the power of the model and include other factors that may be related to COVID-19 preventive behavior.

Association of chemotherapy and subjective cognitive impairment in breast cancer patients: Meta-analysis of longitudinal prospective cohort studies.

PURPOSE: This meta-analysis with longitudinal prospective cohort studies aimed to (a) determine whether chemotherapy is associated with time-dependent subjective cognitive impairment outcomes in breast cancer patients, and (b) identify the time point with the highest impact of chemotherapy on subjective cognitive impairment. METHODS: Data were gathered from PubMed, EMBASE, CINAHL, PsycInfo, and the Cochrane Library. The mean differences of the subjective cognitive impairment level between the chemotherapy-treated patients and controls (patients not treated by chemotherapy and healthy subjects) were calculated using effect sizes (Hedges' g) by clinical time periods. The five clinical time periods were (a) baseline, (b) during chemotherapy, (c) within 1 month postchemotherapy, (d) within 1 year postchemotherapy, and (e) 1 year or longer postchemotherapy. RESULTS: Longitudinal data from nine data sets from 13 studies were pooled and analyzed. At baseline, chemotherapy-treated patients showed slightly better subjective cognitive impairment compared to patients not treated by chemotherapy and did not differ from healthy controls. Yet, the chemotherapy-treated patients had significantly worse subjective cognitive impairment compared to both type of controls after initiating chemotherapy. The effect sizes for the group differences were larger for the group comparison with healthy controls than the nonchemotherapy control (-0.50 vs. -0.19). The largest effects were found within 1 month postchemotherapy (-0.85), suggesting the acute impact of chemotherapy. CONCLUSIONS: Chemotherapy is associated with subjective cognitive impairment. The impact of chemotherapy appears to be an acute rather than a chronic side effect. Clinicians must consider including the assessment and management of subjective cognitive impairment in their routine practice.

E-health literacy in older adults: an evolutionary concept analysis.

BACKGROUND: Internet technologies have become important for older adults to not only seek, understand, and evaluate information on health management but also apply and share acquired knowledge. Despite the disparity in e-health literacy among older adults, which affects health outcomes, its conceptual definition has not been distinctly clarified in previous studies. This study aimed to analyse the concept of e-health literacy among older adults and to identify its contexts in the nursing field. METHODS: We identified concepts, attributes, antecedents, and consequences of e-health literacy in older adults using Rodgers' evolutionary approach to various fields of study, time, and cultural differences. A literature search was conducted using the National Assembly Library, Research Information Sharing Service, National Digital Science Library, DataBase Periodical Information Academic, PubMed, Cumulative Index to Nursing and Allied Health Literature, Excerpta Medica database, and Cochrane. RESULTS: A total of 28 studies were included, and we categorised the following three attributes: active information seeking, two-way interactive communication, and information utilization/sharing. The antecedents included personal factors, health status, socioeconomic factors, cultural factors, and attitudes toward the Internet while the consequences included increased health interest, health behaviour promotion, and active decision-making. CONCLUSIONS: As e-health literacy in older adults affects their health and quality of life, this study clarifies the concept and provides a conceptual framework for nursing practice and research. Further studies are needed to identify and expand the constantly evolving concept of e-health literacy in older adults.

Staffing Levels and COVID-19 Infections and Deaths in Korean Nursing Homes.

The novel coronavirus disease 2019 (COVID-19) spread rapidly worldwide. Nursing home (NH) residents are the most vulnerable high-risk population to infection. Professional registered nurses' (RNs') infection control is irreplaceable. We used a secondary data analysis method using the government's senior citizen welfare department large data set about all NHs (N = 3,389) across Korea between January 20 and October 20, 2020. Bed size positively associated with the mortality rate (No. of COVID-19 resident deaths / No. of total residents) (p = .048). When the proportion of RNs to total nursing staff was higher, the infection rate was 0.626% lower (p = .049), the mortality rate was 0.088% lower (p = .076), the proportion of confirmed COVID-19 cases per resident out of the total number of NHs was 44.472% lower (p = .041), and the proportion of confirmed COVID-19 deaths per resident out of the total number of NHs was 6.456% lower (p = .055). This study highlighted nurse staffing criteria and suggests that increasing RNs in NHs will reduce infection and mortality rates during the COVID-19 pandemic. We strongly suggest NHs hire at least one RN per day to properly function, and a minimum of four RNs to provide a fully competent RN workforce in long-term care settings in Korean NHs.

Building a Runway to Subjective Happiness: The Role of Fashion Modeling Classes in Promoting Seniors' Mental Well-Being.

This study focuses on senior citizens who are participating in fashion modeling classes. Modeling classes are one of the most prominent educational leisure activities that has recently garnered the attention of the elderly population. The effect of flow experience in modeling classes on perceived happiness in life was considered. Since the activities related to modeling classes are related to fashion and appearance, the mediating roles of confidence in fashion and appearance satisfaction were included as hypotheses. Survey data of 168 women aged 50 years or older were analyzed using the PROCESS macro for SPSS and SmartPLS. Flow experience was found to have a positive effect on subjective happiness, confidence in fashion, and appearance satisfaction. However, confidence in fashion had a significant impact on appearance satisfaction but not on subjective happiness. Appearance satisfaction also had a significant effect on subjective happiness. Appearance satisfaction had a significant mediation effect from flow experience to subjective happiness, but confidence in fashion did not have significant influence in the process. However, the serial multiple mediation effect through confidence in fashion and appearance satisfaction was detected to be significant from flow experience to subjective happiness. The results are expected to help establish the direction of leisure education programs for seniors and bring progress to the research agenda on the impact of fashion confidence and appearance satisfaction on senior citizens.

Comparative evaluations of single-item pain-intensity measures in cancer patients: Numeric rating scale vs. verbal rating scale.

AIMS AND OBJECTIVES: To evaluate the psychometric quality of two single-item pain-intensity measures: the Numeric Rating Scale (NRS) and the Verbal Rating Scale (VRS). BACKGROUND: Measuring pain intensity is a vital step in initiating symptom management and evaluating the effectiveness of interventions with cancer patients. Single-item pain-intensity measures of the NRS and VRS format have been evaluated to be acceptable for use in clinical practice and research; however, evidence to choose one over the other, as a standardised pain-assessment format, is insufficient. DESIGN: Descriptive correlational study. The study was guided and reported following the STROBE guideline. METHODS: Data accrued at two time points during cancer treatment with a total of 249 patients treated in a Korean University Hospital. Two single-item measures were constructed to assess pain intensity over 1 week. The Brief Pain Inventory (BPI; pain intensity subscale and interference subscale) and the functional assessment of chronic illness therapy-fatigue were the criterion. Convergent and concurrent validity were tested with Pearson's correlations. RESULTS: In the convergent-validity evaluation of the cross-sectional association with the BPI, the NRS showed a much higher level of association than the VRS (0.81 versus 0.61). In convergent validity with a longitudinal association with the BPI, the NRS score change had a much higher level of association (0.61 versus 0.37). In concurrent-validity evaluation, the NRS and VRS showed similar levels of associations with fatigue (-0.48 versus -0.49). Yet, the NRS showed statistically higher levels of correlation with functional limitations than the VRS (0.55 versus 0.42), comparable to the concurrent validity of the BPI. CONCLUSION: The NRS showed higher validity than VRS when assessing overall pain intensity over the past week. RELEVANCE TO CLINICAL NURSING: Pain assessment is a vital role of nurses in caring for patients with cancer. Current study findings support the use of the single-item NRS pain measure to assess global pain intensity over the past week.

Systematic review of longitudinal studies on chemotherapy-associated subjective cognitive impairment in cancer patients.

OBJECTIVES: This systematic review of longitudinal studies, assessing subjective cognitive impairment (SCI) reported by adult cancer patients, aimed to summarize evidence on the impact of chemotherapy on SCI, identify moderators of SCI, and evaluate methodological issues. METHODS: Data accrued from Pubmed, EMBASE, CINAHL, PsychInfo, and the Cochrane library. Inclusion criteria were original studies, an exclusively adult sample, valid and reliable subjective cognitive measures, and at least one baseline data point prior to and another after the initiation of chemotherapy. Data were collected on the sample composition, data-collection time points, outcome measures, statistical analysis, and major findings (ie, longitudinal changes in prevalence, severity, and associated factors). RESULTS: Forty articles published between 2004 and 2019 were retained: 21 examined chemotherapy-treated patients only, and 19 employed control groups. Findings were mixed, with slightly more studies supporting the impact of chemotherapy on SCI. SCI tended to be more prevalent and severe after initiating chemotherapy, compared with patients' own baseline and controls not treated with chemotherapy. Impact appeared to be acute and more likely limited to subsamples. Most studies examining non-breast-cancer samples reported the lack or limited impact of chemotherapy on SCI. The most consistent moderators were depression and fatigue. Methodological issues regarding sampling design, measurement, and statistical analysis were discussed. CONCLUSION: More rigorously designed longitudinal studies would clarify direct and indirect effects of chemotherapy on SCI.

Solid phase DNA extraction with a flexible bead-packed microfluidic device to detect methicillin-resistant Staphylococcus aureus in nasal swabs.

We have developed a bead-packed microfluidic device with a built-in flexible wall to automate extraction of nucleic acids from methicillin-resistant Staphylococcus aureus (MRSA) in nasal swabs. The flexible polydimethylsiloxane (PDMS) membrane was designed to manipulate the surface-to-volume ratio (SVR) of bead-packed chambers in the range of 0.05 to 0.15 (µm(-1)) for a typical solid phase extraction protocol composed of binding, washing, and eluting. In particular, the pneumatically assisted close packing of beads led to an invariant SVR (0.15 µm(-1)) even with different bead amounts (10-16 mg), which allowed for consistent operation of the device and improved capture efficiency for bacteria cells. Furthermore, vigorous mixing by asynchronous membrane vibration enabled ca. 90% DNA recovery with ca. 10 µL of liquid solution from the captured cells on the bead surfaces. The full processes to detect MRSA in nasal swabs, i.e., nasal swab collection, prefiltration, on-chip DNA extraction, and real-time polymerase chain reaction (PCR) amplification, were successfully constructed and carried out to validate the capability to detect MRSA in nasal swab samples. This flexible microdevice provided an excellent analytical PCR detection sensitivity of ca. 61 CFU/swab with 95% confidence interval, which turned out to be higher than or similar to that of the commercial DNA-based MRSA detection techniques. This excellent performance would be attributed to the capability of the flexible bead-packed microdevice to enrich the analyte from a large initial sample (e.g., 1 mL) into a microscale volume of eluate (e.g., 10 µL). The proposed microdevice will find many applications as a solid phase extraction method toward various sample-to-answer systems.

Miniaturized bead-beating device to automate full DNA sample preparation processes for gram-positive bacteria.

We have developed a miniaturized bead-beating device to automate nucleic acids extraction from Gram-positive bacteria for molecular diagnostics. The microfluidic device was fabricated by sandwiching a monolithic flexible polydimethylsiloxane (PDMS) membrane between two glass wafers (i.e., glass-PDMS-glass), which acted as an actuator for bead collision via its pneumatic vibration without additional lysis equipment. The Gram-positive bacteria, S. aureus and methicillin-resistant S. aureus, were captured on surface-modified glass beads from 1 mL of initial sample solution and in situ lyzed by bead-beating operation. Then, 10 µL or 20 µL of bacterial DNA solution was eluted and amplified successfully by real-time PCR. It was found that liquid volume fraction played a crucial role in determining the cell lysis efficiency in a confined chamber by facilitating membrane deflection and bead motion. The miniaturized bead-beating operation disrupted most of S. aureus within 3 min, which turned out to be as efficient as the conventional benchtop vortexing machine or the enzyme-based lysis technique. The effective cell concentration was significantly enhanced with the reduction of initial sample volume by 50 or 100 times. Combination of such analyte enrichment and in situ bead-beating lysis provided an excellent PCR detection sensitivity amounting to ca. 46 CFU even for the Gram-positive bacteria. The proposed bead-beating microdevice is potentially useful as a nucleic acid extraction method toward a PCR-based sample-to-answer system.

Controlled antibody immobilization onto immunoanalytical platforms by synthetic peptide.

Antibody immobilization on a solid surface is inevitable in the preparation of immunochips/sensors. Antibody-binding proteins such as proteins A and G have been extensively employed to capture antibodies on sensor surfaces with right orientations, maintaining their full functionality. Because of their synthetic versatility and stability, in general, small molecules have more advantages than proteins. Nevertheless, no small molecule has been used for oriented and specific antibody immobilization. Here is described a novel strategy to immobilize an antibody on various sensor surfaces by using a small antibody-binding peptide. The peptide binds specifically to the Fc domain of immunoglobulin G (IgG) and, therefore, affords a properly oriented antibody surface. Surface plasmon resonance analysis indicated that a peptide linked to a gold chip surface through a hydrophilic linker efficiently captured human and rabbit IgGs. Moreover, antibodies captured by the peptide exhibited higher antigen binding capacity compared with randomly immobilized antibodies. Peptide-mediated antibody immobilization was successfully applied on the surfaces of biosensor substrates such as magnetic particles and glass slides. The antibody-binding peptide conjugate introduced in this work is the first small molecule linker that offers a highly stable and specific surface platform for antibody immobilization in immunoassays.

Direct immobilization of protein g variants with various numbers of cysteine residues on a gold surface.

Protein G is an antibody binding protein, which specifically targets the Fc region of an antibody. It therefore has been widely used to immobilize different types of antibodies in numerous immunoassays. Here, we have engineered Streptococcus protein G to contain various numbers of cysteine residues at the N-terminus and therefore to form well-oriented protein G films on bare gold. SPR and SPR imaging analyses indicated that a gold surface treated with cysteine-tagged protein G possesses a superior antibody binding ability compared to one treated with tag-free protein G. AFM images indicated a higher surface coverage by antibody binding on the cysteine-tagged protein G surface than the intact protein G surface. The proper orientation of cysteine-tagged protein G on a gold surface also afforded better orientation of immobilized antibodies, resulting in enhanced antigen detection. Moreover, the protein G surfaces maintained their high antibody binding ability during multiple rounds of antibody interaction tests. The cysteine-tagged protein G constructed in this study can be a valuable link for oriented antibody immobilization in a variety of immunosensors.

Oriented immobilization of antibodies with GST-fused multiple Fc-specific B-domains on a gold surface.

We have constructed a novel platform for the oriented buildup of immunoglobulins on a gold surface for a surface plasmon resonance imaging microarray. To this end, genetically engineered glutathione S-transferase proteins bearing one, two, and three Fc-specific B-domains in protein G from Streptococci (GST-GB1, -GB2, and -GB3, respectively) were produced. In order to tether these GST-GBx proteins specifically, a novel glutathione-derivatized ligand (LA-GSH) was also synthesized from a biaminated tri(ethylene glycol) backbone. Each end of the backbone was further functionalized with a maleimide group for a glutathione modification and a lipoic acid for surface immobilization. The glutathione ligand demonstrated a negligible nonspecific protein adsorption toward other spectator proteins while showing a strong specific association toward GST-GBx proteins. This Fc-specific surface exhibited at least a 2-fold enhancement in the immunoglobulin density (from human and mouse) with its antigen capture capability totally conserved compared to a covalently tethered GBx proteins. A single antibody tethered on the GST-GB3 is estimated to capture two antigens (enhanced green fluorescent protein), and this antigen capture ratio seems to be the most efficient value ever observed.

On-chip Escherichia coli culture, purification, and detection of expressed proteins.

In a recent study, we reported the results of a rapid high-throughput expression analysis of the affinity-tagged proteins present in total cell lysates, using a surface plasmon resonance (SPR) imaging protein chip system. In this paper, we describe a novel method, which is able to sequentially carry out a recombinant Escherichia coli culture, as well as the detection and purification of the expressed proteins on a single microwell chip, fabricated on a two-dimensional thin gold film. Following the induction of the protein on the microwell chip, the E. coli cells were lysed on the chip via the addition of lysozymes, and the expressed glutathione S-transferase-fused green fluorescent protein (GST-GFP) was then purified on the chip via affinity interaction with the glutathionylated gold surface of the chip. Finally, the expressed protein was directly detected using the surface plasmon resonance (SPR) imaging system. This system saves a substantial amount of time, experimental resources, and labor, by allowing for the complicated and labor-intensive procedures inherent to the production of recombinant proteins to be conducted on a single microwell chip, simply and economically.

Surface plasmon resonance imaging protein arrays for analysis of triple protein interactions of HPV, E6, E6AP, and p53.

We have developed a surface plasmon resonance (SPR)-based protein microarray to study protein-protein interactions in a high-throughput mode. As a model system, triple protein interactions have been explored with human papillomaviral E6 protein, tumor suppressor p53, and ubiquitin ligase E6AP. Human papillomavirus (HPV) is known to be a causative agent of cervical cancer. Upon infection, the viral E6 protein forms a heterotrimeric protein complex with p53 and E6AP. The formation of the complex eventually results in the degradation of p53. In the present study, a GST-fused E6AP protein was layered onto a glutathione (GSH)-modified gold chip surface. The specific binding of GST-E6AP protein onto the gold chip surface was facilitated through the affinity of GST to its specific ligand GSH. The interacting proteins (E6 and/or p53) were then spotted. Detection of the interaction was performed using a SPR imaging (SPRI) technique. The resulting SPRI intensity data showed that the protein-protein interactions of E6AP, E6, and p53 were detected in a concentration-dependent manner, suggesting that the SPRI-based microarray system can be an effective tool to study protein-protein interactions where multiple proteins are involved.

Detection of Bax protein conformational change using a surface plasmon resonance imaging-based antibody chip.

We describe an antibody chip technology that uses a surface plasmon resonance (SPR) imaging system to examine the conformational change of a protein. In this study, we used Bax protein, a pro-apoptotic member of the Bcl-2 family of proteins, as a model protein to investigate the conformational alteration triggered by a TNF-related apoptosis-inducing ligand (TRAIL), a potent inducer of apoptosis. To develop the antibody chip for detecting the Bax conformational change, we immobilized Bax monoclonal antibody 6A7, which recognizes only a conformationally changed Bax protein on a gold surface. The resultant immobilized Bax antibodies provided specific and accurate measurements of the active conformation-specific epitope in the apoptotic cancer cells treated with the TRAIL; these measurements corresponded to the data obtained by immunoprecipitation analysis using an active conformation-specific Bax antibody (6A7). The results of our study indicated that TRAIL-induced Bax structural change could be monitored quickly and simply using an SPR imaging system, thus demonstrating the potential for using such a system for the analysis of conformational properties of target proteins.