1
|
Reply to Viner, A.; Ayrey, S. Comment on “Scheepers et al. Comparative Performance Testing of Respirator versus Surgical Mask Using a Water Droplet Spray Model. Int. J. Environ. Res. Public Health 2021, 18, 1599”. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19106296. [PMID: 35627832 PMCID: PMC9141231 DOI: 10.3390/ijerph19106296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 05/19/2022] [Indexed: 11/29/2022]
|
2
|
Barriers to and Facilitators of Using a One Button Tracker and Web-Based Data Analytics Tool for Personal Science: Exploratory Study. JMIR Form Res 2022; 6:e32704. [PMID: 35230247 PMCID: PMC8924778 DOI: 10.2196/32704] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 12/12/2021] [Accepted: 12/30/2021] [Indexed: 01/05/2023] Open
Abstract
Background
Individuals’ self-tracking of subjectively experienced phenomena related to health can be challenging, as current options for instrumentation often involve too much effort in the moment or rely on retrospective self-reporting, which is likely to impair accuracy and compliance.
Objective
This study aims to assess the usability and perceived usefulness of low-effort, in-the-moment self-tracking using simple instrumentation and to establish the amount of support needed when using this approach.
Methods
In this exploratory study, the One Button Tracker—a press-button device that records time stamps and durations of button presses—was used for self-tracking. A total of 13 employees of an academic medical center chose a personal research question and used the One Button Tracker to actively track specific subjectively experienced phenomena for 2 to 4 weeks. To assess usability and usefulness, we combined qualitative data from semistructured interviews with quantitative results from the System Usability Scale.
Results
In total, 29 barriers and 15 facilitators for using the One Button Tracker were found. Ease of use was the most frequently mentioned facilitator. The One Button Tracker’s usability received a median System Usability Scale score of 75.0 (IQR 42.50), which is considered as good usability. Participants experienced effects such as an increased awareness of the tracked phenomenon, a confirmation of personal knowledge, a gain of insight, and behavior change. Support and guidance during all stages of the self-tracking process were judged as valuable.
Conclusions
The low-effort, in-the-moment self-tracking of subjectively experienced phenomena has been shown to support personal knowledge gain and health behavior change for people with an interest in health promotion. After addressing barriers and formally validating the collected data, self-tracking devices may well be helpful for additional user types or health questions.
Collapse
|
3
|
Ethical Aspects of Personal Science for Persons with Parkinson's Disease: What Happens When Self-Tracking Goes from Selfcare to Publication? JOURNAL OF PARKINSON'S DISEASE 2022; 11:1927-1933. [PMID: 34120915 PMCID: PMC8609698 DOI: 10.3233/jpd-212647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Accepted: 05/21/2021] [Indexed: 11/29/2022]
Abstract
Using Parkinson's disease as an exemplary chronic condition, this Commentary discusses ethical aspects of using self-tracking for personal science, as compared to using self-tracking in the context of conducting clinical research on groups of study participants. Conventional group-based clinical research aims to find generalisable answers to clinical or public health questions. The aim of personal science is different: to find meaningful answers that matter first and foremost to an individual with a particular health challenge. In the case of personal science, the researcher and the participant are one and the same, which means that specific ethical issues may arise, such as the need to protect the participant against self-harm. To allow patient-led research in the form of personal science in the Parkinson field to evolve further, the development of a specific ethical framework for self-tracking for personal science is needed.
Collapse
|
4
|
Comparative Performance Testing of Respirator versus Surgical Mask Using a Water Droplet Spray Model. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18041599. [PMID: 33567665 PMCID: PMC7915861 DOI: 10.3390/ijerph18041599] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 01/31/2021] [Accepted: 02/04/2021] [Indexed: 01/04/2023]
Abstract
BACKGROUND During the SARS-CoV-2 pandemic, there was shortage of the standard respiratory protective equipment (RPE). The aim of this study was to develop a procedure to test the performance of alternative RPEs used in the care of COVID-19 patients. METHODS A laboratory-based test was developed to compare RPEs by total inward leakage (TIL). We used a crossflow nebulizer to produce a jet spray of 1-100 µm water droplets with a fluorescent marker. The RPEs were placed on a dummy head and sprayed at distances of 30 and 60 cm. The outcome was determined as the recovery of the fluorescent marker on a membrane filter placed on the mouth of the dummy head. RESULTS At 30 cm, a type IIR surgical mask gave a 17.7% lower TIL compared with an FFP2 respirator. At 60 cm, this difference was similar, with a 21.7% lower TIL for the surgical mask compared to the respirator. When adding a face shield, the TIL at 30 cm was further reduced by 9.5% for the respirator and 16.6% in the case of the surgical mask. CONCLUSIONS A safe, fast and very sensitive test method was developed to assess the effectiveness of RPE by comparison under controlled conditions.
Collapse
|
5
|
The effect of a multifaceted evidence-based practice programme for nurses on knowledge, skills, attitudes, and perceived barriers: A cohort study. NURSE EDUCATION TODAY 2018; 63:6-11. [PMID: 29407262 DOI: 10.1016/j.nedt.2018.01.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 11/24/2017] [Accepted: 01/11/2018] [Indexed: 06/07/2023]
Abstract
BACKGROUND The Dutch professional nursing standard of 2012 stipulates that Dutch nursing practices are to be evidence-based. Not all practicing nurses can satisfy these requirements, therefore, an educational programme about Evidence-Based Practice (EBP) was developed for a Dutch teaching hospital. OBJECTIVE The aim of this study was to measure the effects of a six month in-house EBP programme on knowledge, skills, attitudes, and perceived barriers of nurses (four European Credits equals two US Credit Hours). METHODS A multiple-cohort study was conducted with a pre-post-test design. In the period of 2011-2015, a total of 58 nurses (9 cohorts) followed the programme. Baseline and follow-up assessments consisted of three questionnaires each: the Dutch Modified Fresno, the two subscales of the McColl questionnaire, and the BARRIER scale to assess knowledge and skills, attitudes, and perceived barriers, respectively. RESULTS Fifty nurses completed both assessments. The results demonstrated that actual knowledge and skills significantly increased by approximately 40%. Self-perceived knowledge increased significantly, while attitudes towards EBP remained (moderately) positive. Perceived barriers did not notably change except for the Research subscale which received many "no opinion" responses prior to the programme but fewer afterwards. CONCLUSIONS Our multifaceted in-house EBP programme led to a significant improvement of approximately 40% in EBP knowledge and skills of participating nurses. Most nurses who followed the EBP programme are currently applying their knowledge and skills in practice. Managerial support and allocated time for EBP are important facilitators for its implementation. Furthermore, to maintain and expand nurses' EBP knowledge and skills and translate them into practice, follow-up interventions, such as journal clubs, may well be beneficial. Based on the positive results of our programme, we will implement it throughout the hospital with an emphasis on training more groups of nurses.
Collapse
|
6
|
Key Components in eHealth Interventions Combining Self-Tracking and Persuasive eCoaching to Promote a Healthier Lifestyle: A Scoping Review. J Med Internet Res 2017; 19:e277. [PMID: 28765103 PMCID: PMC5558041 DOI: 10.2196/jmir.7288] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/03/2017] [Accepted: 06/05/2017] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND The combination of self-tracking and persuasive eCoaching in automated interventions is a new and promising approach for healthy lifestyle management. OBJECTIVE The aim of this study was to identify key components of self-tracking and persuasive eCoaching in automated healthy lifestyle interventions that contribute to their effectiveness on health outcomes, usability, and adherence. A secondary aim was to identify the way in which these key components should be designed to contribute to improved health outcomes, usability, and adherence. METHODS The scoping review methodology proposed by Arskey and O'Malley was applied. Scopus, EMBASE, PsycINFO, and PubMed were searched for publications dated from January 1, 2013 to January 31, 2016 that included (1) self-tracking, (2) persuasive eCoaching, and (3) healthy lifestyle intervention. RESULTS The search resulted in 32 publications, 17 of which provided results regarding the effect on health outcomes, 27 of which provided results regarding usability, and 13 of which provided results regarding adherence. Among the 32 publications, 27 described an intervention. The most commonly applied persuasive eCoaching components in the described interventions were personalization (n=24), suggestion (n=19), goal-setting (n=17), simulation (n=17), and reminders (n=15). As for self-tracking components, most interventions utilized an accelerometer to measure steps (n=11). Furthermore, the medium through which the user could access the intervention was usually a mobile phone (n=10). The following key components and their specific design seem to influence both health outcomes and usability in a positive way: reduction by setting short-term goals to eventually reach long-term goals, personalization of goals, praise messages, reminders to input self-tracking data into the technology, use of validity-tested devices, integration of self-tracking and persuasive eCoaching, and provision of face-to-face instructions during implementation. In addition, health outcomes or usability were not negatively affected when more effort was requested from participants to input data into the technology. The data extracted from the included publications provided limited ability to identify key components for adherence. However, one key component was identified for both usability and adherence, namely the provision of personalized content. CONCLUSIONS This scoping review provides a first overview of the key components in automated healthy lifestyle interventions combining self-tracking and persuasive eCoaching that can be utilized during the development of such interventions. Future studies should focus on the identification of key components for effects on adherence, as adherence is a prerequisite for an intervention to be effective.
Collapse
|
7
|
Do activity monitors increase physical activity in adults with overweight or obesity? A systematic review and meta-analysis. Obesity (Silver Spring) 2016; 24:2078-91. [PMID: 27670401 DOI: 10.1002/oby.21619] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 06/18/2016] [Accepted: 06/27/2016] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To systematically assess contemporary knowledge regarding behavioral physical activity interventions including an activity monitor (BPAI+) in adults with overweight or obesity. METHODS PubMed/MEDLINE, Embase, CINAHL, PsycINFO, CENTRAL, and PEDro were searched for eligible full-text articles up to 1 July 2015. Studies eligible for inclusion were (randomized) controlled trials describing physical activity outcomes in adults with overweight or obesity. Methodological quality was independently assessed employing the Cochrane Collaboration's tool for risk of bias. RESULTS Fourteen studies (1,157 participants) were included for systematic review and 11 for meta-analysis. A positive trend in BPAI+ effects on several measures of physical activity was ascertained compared with both wait list or usual care and behavioral physical activity interventions without an activity monitor (BPAI-). No convincing evidence of BPAI+ effectiveness on weight loss was found compared with BPAI-. CONCLUSIONS Behavioral physical activity interventions with an activity monitor increase physical activity in adults with overweight or obesity. Also, adding an activity monitor to behavioral physical activity interventions appears to increase the effect on physical activity, although current evidence has not yet provided conclusive evidence for its effectiveness.
Collapse
|
8
|
Reliability and validity of ten consumer activity trackers. BMC Sports Sci Med Rehabil 2015; 7:24. [PMID: 26464801 PMCID: PMC4603296 DOI: 10.1186/s13102-015-0018-5] [Citation(s) in RCA: 272] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 10/05/2015] [Indexed: 01/08/2023]
Abstract
Background Activity trackers can potentially stimulate users to increase their physical activity behavior. The aim of this study was to examine the reliability and validity of ten consumer activity trackers for measuring step count in both laboratory and free-living conditions. Method Healthy adult volunteers (n = 33) walked twice on a treadmill (4.8 km/h) for 30 min while wearing ten different activity trackers (i.e. Lumoback, Fitbit Flex, Jawbone Up, Nike+ Fuelband SE, Misfit Shine, Withings Pulse, Fitbit Zip, Omron HJ-203, Yamax Digiwalker SW-200 and Moves mobile application). In free-living conditions, 56 volunteers wore the same activity trackers for one working day. Test-retest reliability was analyzed with the Intraclass Correlation Coefficient (ICC). Validity was evaluated by comparing each tracker with the gold standard (Optogait system for laboratory and ActivPAL for free-living conditions), using paired samples t-tests, mean absolute percentage errors, correlations and Bland-Altman plots. Results Test-retest analysis revealed high reliability for most trackers except for the Omron (ICC .14), Moves app (ICC .37) and Nike+ Fuelband (ICC .53). The mean absolute percentage errors of the trackers in laboratory and free-living conditions respectively, were: Lumoback (−0.2, −0.4), Fibit Flex (−5.7, 3.7), Jawbone Up (−1.0, 1.4), Nike+ Fuelband (−18, −24), Misfit Shine (0.2, 1.1), Withings Pulse (−0.5, −7.9), Fitbit Zip (−0.3, 1.2), Omron (2.5, −0.4), Digiwalker (−1.2, −5.9), and Moves app (9.6, −37.6). Bland-Altman plots demonstrated that the limits of agreement varied from 46 steps (Fitbit Zip) to 2422 steps (Nike+ Fuelband) in the laboratory condition, and 866 steps (Fitbit Zip) to 5150 steps (Moves app) in the free-living condition. Conclusion The reliability and validity of most trackers for measuring step count is good. The Fitbit Zip is the most valid whereas the reliability and validity of the Nike+ Fuelband is low.
Collapse
|
9
|
Abstract
Activity trackers like Fitbit are used for self-tracking of physical activity by an increasing number of individuals. Comparing physical activity scores with peers can contribute to the desired behavioural change. However, for meaningful social comparison a high inter-device reliability is paramount. This study aimed to determine the inter-device reliability of Fitbit activity trackers in measuring steps. Ten activity trackers (Fitbit Ultra) were worn by a single person (male, 46 years) during eight consecutive days. Inter-device reliability was assessed on three different levels of aggregation (minutes, hours, days) with various methods, including intra-class correlation coefficient (ICC), Bland-Altman plots, limits of agreement (LOA) and Mixed Model Analysis. Results showed that the inter-device reliability of the Fitbit in measuring steps is good at all levels of aggregation (minutes, hours, days), but especially when steps were measured per day. This implies that individuals can reliably compare their daily physical activity scores with peers.
Collapse
|
10
|
Lesion detection performance: comparative analysis of low-dose CT data of the chest on two hybrid imaging systems. J Nucl Med Technol 2015; 43:47-52. [PMID: 25613338 DOI: 10.2967/jnmt.114.147447] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Incidental findings on low-dose CT images obtained during hybrid imaging are an increasing phenomenon as CT technology advances. Understanding the diagnostic value of incidental findings along with the technical limitations is important when reporting image results and recommending follow-up, which may result in an additional radiation dose from further diagnostic imaging and an increase in patient anxiety. This study assessed lesions incidentally detected on CT images acquired for attenuation correction on two SPECT/CT systems. METHODS An anthropomorphic chest phantom containing simulated lesions of varying size and density was imaged on an Infinia Hawkeye 4 and a Symbia T6 using the low-dose CT settings applied for attenuation correction acquisitions in myocardial perfusion imaging. Twenty-two interpreters assessed 46 images from each SPECT/CT system (15 normal images and 31 abnormal images; 41 lesions). Data were evaluated using a jackknife alternative free-response receiver-operating-characteristic analysis (JAFROC). RESULTS JAFROC analysis showed a significant difference (P < 0.0001) in lesion detection, with the figures of merit being 0.599 (95% confidence interval, 0.568, 0.631) and 0.810 (95% confidence interval, 0.781, 0.839) for the Infinia Hawkeye 4 and Symbia T6, respectively. Lesion detection on the Infinia Hawkeye 4 was generally limited to larger, higher-density lesions. The Symbia T6 allowed improved detection rates for midsized lesions and some lower-density lesions. However, interpreters struggled to detect small (5 mm) lesions on both image sets, irrespective of density. CONCLUSION Lesion detection is more reliable on low-dose CT images from the Symbia T6 than from the Infinia Hawkeye 4. This phantom-based study gives an indication of potential lesion detection in the clinical context as shown by two commonly used SPECT/CT systems, which may assist the clinician in determining whether further diagnostic imaging is justified.
Collapse
|
11
|
Evaluation of DVH-based treatment plan verification in addition to gamma passing rates for head and neck IMRT. Radiother Oncol 2014; 112:389-95. [DOI: 10.1016/j.radonc.2014.08.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 07/18/2014] [Accepted: 08/02/2014] [Indexed: 12/25/2022]
|
12
|
The impact of gastrointestinal and genitourinary toxicity on health related quality of life among irradiated prostate cancer patients. Radiother Oncol 2014; 110:284-90. [DOI: 10.1016/j.radonc.2013.11.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 06/18/2013] [Accepted: 11/10/2013] [Indexed: 11/12/2022]
|
13
|
Quality of life among prostate cancer patients: a prospective longitudinal population-based study. Radiother Oncol 2013; 108:299-305. [PMID: 23932157 DOI: 10.1016/j.radonc.2013.06.039] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 06/18/2013] [Accepted: 06/19/2013] [Indexed: 11/30/2022]
Abstract
PURPOSE To investigate the course of quality of life (QoL) among prostate cancer patients treated with external beam radiotherapy and to compare the results with QoL of a normal age-matched reference population. PATIENTS AND METHODS The study population was composed of 227 prostate cancer patients, treated with radiotherapy. The EORTC QLQ-C30 was used to assess QoL before radiotherapy and six months, one year, two years and three years after completion of radiotherapy. Mixed model analyses were used to investigate longitudinal changes in QoL. QoL of prostate cancer patients was compared to that of a normative cohort using a multivariate analysis of covariance. RESULTS A significant decline in QoL was observed after radiotherapy (p<0.001). The addition of hormonal therapy to radiotherapy was associated with a lower level of role functioning. Patients with coronary heart disease and or chronic obstructive pulmonary disease or asthma had a significantly worse course in QoL. Although statistically significant, all differences were classified as small or trivial. CONCLUSION Prostate cancer patients experience a small worsening of QoL as compared with baseline and as compared with a normal reference population. As co-morbidity modulates patients' post-treatment QoL, a proper assessment of co-morbidity should be included in future longitudinal analyses on QoL.
Collapse
|
14
|
Abstract
Successful transplantation of pancreatic tissue has been demonstrated to be an efficacious method of restoring glycemic control in type 1 diabetic patients. To establish graft acceptance patients require lifelong immunosuppression, which in turn is associated with severe deleterious side effects. Microencapsulation is a technique that enables the transplantation of pancreatic islets in the absence of immunosuppression by protecting the islet tissue through a mechanical barrier. This protection may even allow for the transplantation of animal tissue, which opens the perspective of using animal donors as a means to solve the problem of organ shortage. Microencapsulation is not yet applied in clinical practice, mainly because encapsulated islet graft survival is limited. In the present review we discuss the principal causes of microencapsulated islet graft failure, which are related to a lack of biocompatibility, limited immunoprotective properties, and hypoxia. Next to the causes of encapsulated islet graft failure we discuss possible improvements in the encapsulation technique and additional methods that could prolong encapsulated islet graft survival. Strategies that may well support encapsulated islet grafts include co-encapsulation of islets with Sertoli cells, the genetic modification of islet cells, the creation of an artificial implantation site, and the use of alternative donor sources. We conclude that encapsulation in combination with one or more of these additional strategies may well lead to a simple and safe transplantation therapy as a cure for diabetes.
Collapse
|
15
|
Effective removal of alginate-poly-L-lysine microcapsules from pancreatic islets by use of trypsin-EDTA. J Biomed Mater Res A 2004; 67:679-83. [PMID: 14566813 DOI: 10.1002/jbm.a.10023] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Although the transplantation of alginate-poly-L-lysine-alginate encapsulated islets of Langerhans usually is successful, graft survival is still limited. Molecular analysis by RT-PCR of the encapsulated islets may provide insight into the mechanisms that affect islets during graft failure. However, RT-PCR on encapsulated islets is not possible because the poly-L-lysine of the capsule interferes with both cDNA synthesis and PCR amplification. We applied a method that mechanically removes the microcapsules from the islets after a short trypsin-EDTA treatment (decapsulation), thereby enabling RT-PCR analysis. The results of this study show that the decapsulation procedure does not affect islet vitality and has only minor effects on islet function and morphology. The decapsulation does not affect GAPDH, beta-actin, Bcl-2, or Bax gene expression. This method is an improvement over the time-consuming manual dissection of microcapsules because it allows for the rapid and relatively harmless removal of capsules on a larger scale. Decapsulation offers the possibility of applying RT-PCR, as well as other methods, which cannot be performed on encapsulated islets.
Collapse
|
16
|
Abstract
BACKGROUND Encapsulation significantly prolongs islet graft survival in the absence of immunosuppression. However, encapsulated islet graft survival is limited to periods of several months. Part of the encapsulated islet graft is affected by a nonprogressive pericapsular overgrowth. To investigate whether macrophages on overgrown capsules affect neighboring nonovergrown encapsulated islets, encapsulated islets were studied during coculture. MATERIALS AND METHODS Encapsulated islet function, islet vitality, and islet cell replication were assessed, as well as the mRNA expression of Bcl-2, Bax, inducible nitric oxide synthase, and monocyte chemoattractant protein-1 in encapsulated islets after 48 h of culture together with microcapsules with macrophage overgrowth. Overgrown capsules were retrieved from the rat peritoneum, three weeks after implantation of an encapsulated islet graft. RESULTS Coculture was associated with inhibition of the stimulated insulin secretion, with decreased cell replication, and with increased cell necrosis, but not with apoptosis of encapsulated islet cells. mRNA expression levels in encapsulated islets after coculture were not different from controls, except for a decrease in Bax mRNA. We found a high level of nitrite, as an indicator of nitric oxide production, but not an increase in inducible nitric oxide synthase mRNA in islets. This, in combination with the absence of increase in monocyte chemoattractant protein-1 mRNA and the lack of apoptosis, indicates that neither interleukin-1beta nor tumor necrosis factor-alpha was responsible for the deleterious effects of coculture on encapsulated islets. CONCLUSIONS Nonovergrown encapsulated islets are affected by the overgrowth on encapsulated islets in their close proximity. This overgrowth contains macrophages that produce nitric oxide which, rather than cytokines, may be held responsible for the deleterious effect on the neighboring encapsulated islets.
Collapse
|
17
|
An EGP-2/Ep-CAM-expressing transgenic rat model to evaluate antibody-mediated immunotherapy. Cancer Immunol Immunother 1999; 48:303-11. [PMID: 10473805 PMCID: PMC11037153 DOI: 10.1007/s002620050579] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The human pancarcinoma-associated epithelial glycoprotein-2 (EGP-2), also known as 17-1A or Ep-CAM, is a 38-kDa transmembrane antigen, commonly used for targeted immunotherapy of carcinomas. Although strongly expressed by most carcinomas, EGP-2 is also expressed in most simple epithelia. To evaluate treatment-associated effects and side-effects on tumor and normal tissue respectively, we generated an EGP-2-expressing transgenic Wistar rat. To express the cDNA of the EGP-2 in an epithelium-specific manner, the 5' and 3' distal flanking regions of the human keratin 18 (K18) gene were used. EGP-2 protein expression was observed in the liver and pancreas, whereas EGP-2 mRNA could also be detected in lung, intestine, stomach and kidney tissues. In this rat, EGP-2-positive tumors can be induced by injecting a rat-derived carcinoma cell line transfected with the GA733-2 cDNA encoding EGP-2. Transgenic rats were used to study specific in vivo localization of an i.v. anti-EGP-2 monoclonal antibody, MOC31, applied i.v. Immunohistochemical analyses showed the specific localization of MOC31 in s.c. induced EGP-2-positive tumors, as well as in the liver. In contrast, in EGP-2-transgenic rats, MOC31 did not bind to EGP-2-negative tumors, the pancreas, or other normal tissues in vivo. In conclusion, an EGP-2-transgenic rat model has been generated that serves as a model to evaluate the efficacy and safety of a variety of anti-EGP-2-based immunotherapeutic modalities.
Collapse
MESH Headings
- Animals
- Animals, Genetically Modified
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacokinetics
- Antibodies, Monoclonal/therapeutic use
- Antigens, Neoplasm/biosynthesis
- Antigens, Neoplasm/genetics
- Antigens, Neoplasm/immunology
- Carcinoma/immunology
- Carcinoma/pathology
- Carcinoma/therapy
- Cell Adhesion Molecules/biosynthesis
- Cell Adhesion Molecules/genetics
- Cell Adhesion Molecules/immunology
- DNA, Complementary/genetics
- Epithelial Cell Adhesion Molecule
- Epithelial Cells/metabolism
- Female
- Humans
- Immunization, Passive
- Immunoenzyme Techniques
- Keratins/genetics
- Male
- Neoplasm Transplantation
- Organ Specificity
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Rats
- Rats, Wistar
- Recombinant Fusion Proteins/biosynthesis
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/immunology
- Transfection
- Tumor Cells, Cultured
- Viscera/metabolism
Collapse
|