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Trust us... We're Doctors : Science, Media, and Ethics in the Hwang stem cell Controversy
Robert Sparrow 서울대학교 언론정보연구소 2006 언론정보연구 Vol.43 No.1
When doubts were first raised about the veracity of thedramatic advances in stem cell research announced by Professor Hwang Woo-Suk, a significant minority response was to question the qualifications of journalists to investigate the matter. In this paper I examine the contemporary relationships between science, scientists, the public, and the media. In the modern context the progress of science often relies on the media to mobilise public support for research and also for the purpose of communication within the scientific community. As a result, attempts to counterpose "science" and "the media" should be treated with some caution. dl argue that because of the essential role played by ethics in good science, journalists may in fact sometimes be well placed to investigate scientists. At the conclusion of my paper I draw out some of the implications of my analysis for the ethics of investigative journalism directed towards scientific research.
Kim, Rokho,Sparrow, David,Weiss, Scott,Hu, Howard 大韓産業醫學會 1996 대한직업환경의학회지 Vol.8 No.3
소량의 연 폭로가 혈청 요산 농도의 증가와 연관이 있다는 기존의 단면적 연구가 있어 왔으나 아직 이를 뒷받침하는 경시적 연구는 보고된 바가 없다. 보스톤지역에 거주하는 중년 및 노년 남성 2,000여명의 코호트에서 무작위로 추출된 509명의 연구 대상자로부터 1979년부터 1994년까지 매 3-5년마다 정기적으로 수집되어 냉동 보관된 전혈이나 즉시 채취한 신선한 전혈의 연 농도를 측정하고, 이와 동시에 혈청 요산, 크레아티닌, 그리고 신체 질량 지수, 음주, 흡연 고혈압 등의 잠재적 혼란 변수들을 정기적으로 측정하였다. 혈청 크레아티닌 농도를 포함한 잠재적 혼란 변수들을 통제한 뒤 혈중 연 농도가 혈청 요산 농도와 통계적으로 유의한 양성 연관이 관찰되었다. 혈중 연 농도 수치의 자연로그 변환치 1이 증가함에 따라 약 0.15mg/dL의 혈청 요산 농도가 증가할 것으로 추정되었다. 이러한 연관성은 추적 연구 기간 중 혈중 연 농도가 한번도 25g/dL을 넘지 않은 소량 연 폭로 남성에서도 유의하게 관찰되었다. 이 경시적 연구는 중년 및 노년 남성에서 비교적 소량의 연 폭로가 혈청 요산 농도의 증가와 관련이 있음을 보여준다. 그러나 이러한 연관이 곧 소량 연 폭로와 통풍 발생의 연관을 의미하는지는 아직 알 수 없으며 후속 연구를 필요로 한다.
Unique features of bovine lymphocytes exposed to a staphylococcal enterotoxin
박용호,Sang Un Lee,Witold A. Ferens,Sparrow Samuels,William C. Davis,Lawrence K. Fox,Jong Sam Ahn,Keun Seok Seo,Byoung Sun Chang,황선영,Gregory A. Bohach 대한수의학회 2006 Journal of Veterinary Science Vol.7 No.3
We previously demonstrated that stimulation of bovine peripheral blood mononuclear cells (PBMCs) with staphylococcal enterotoxin C (SEC), led to an inversion of the CD4+:CD8+ T cell ratio and generation of an atypical CD8+ T cell subpopulation expressing CD26. In the present study, we examined T cell apoptosis and proliferation profiles of PBMC subpopulations in cultures stimulated with SEC. Unlike when stimulated with concanavalin A, nucleic acid synthesis in bovine PBMC cultures stimulated with SEC was low during the first four days but increased greatly on day 5. In contrast, nucleic acid synthesis in human PBMC cultures stimulated with SEC increased continuously. To investigate the mechanism of delayed bovine T cell proliferation, various cell phenotypes were monitored. The inversion of the bovine CD4+:CD8+ T cell ratio in PBMC cultures stimulated by SEC was associated with higher proliferation and lower apoptosis of CD8+ T cells compared to CD4+ T cells. The mRNA levels for interleukin (IL)-4 and IL-13 were sustained over 4 days but IL-12 mRNA levels dropped to background on day 2. These data suggest that SEC induces a prolonged Th-2- biased microenvironment, and together with the inversion of the bovine CD4+:CD8+ T cell ratios in bovine PBMC cultures with SEC, may in part explain the inability of the mammary immune system to establish an effective response to Staphylococcus aureus infections.
Photo-products of retinal pigment epithelial bisretinoids react with cellular thiols
Yoon, Kee Dong,Yamamoto, Kazunori,Zhou, Jilin,Sparrow, Janet R. Molecular Vision 2011 Molecular vision Vol.17 No.-
<P><B>Purpose</B></P><P>Bisretinoids such as A2E that accumulate as components of the lipofuscin of retinal pigment epithelial cells are implicated in some retinal disease processes. These compounds undergo light-induced oxidation and cleavage with the latter releasing of a mixture of aldehyde-bearing fragments, including dicarbonyl methylglyoxal. We tested for the reactivity of photooxidation and photodegradation products of A2E with thiol-containing glutathione (GSH).</P><P><B>Methods</B></P><P>In cell-free assays, we measured the ability of photooxo-A2E to competitively inhibit the GSH-mediated reduction of the thiol reagent 5,5′-dithiobis-(2-nitrobenzoic acid). Cellular GSH was assayed colorimetrically. Products of GSH reduction and GSH-adducts were detected by electrospray ionization mass spectrometry (ESI-MS) and GSH and oxidized GSH (glutathione disulfide [GSSG]) were quantified from chromatographic peak areas.</P><P><B>Results</B></P><P>We found that GSH can donate hydrogen atoms to, and form conjugates with, photooxidized forms of the bisretinoid A2E and with its photocleavage products. Reaction with non-photooxidized A2E was not observed. Chemical reduction by GSH involved the donation of a hydrogen atom from each of two GSHs. The ratio of GSH consumed to GSSG formed was consistent with GSH being used for both reduction and adduct formation. With the aid of synthesized standards, methylglyoxal-GSH adducts were identified within mixtures of GSH and photooxidized A2E; the adducts formed noncatalytically and by glutathione-S-transferase mediation.</P><P><B>Conclusions</B></P><P>Reduction and adduct formation by GSH likely limits the reactivity of bisretinoid photoproducts and may aid their elimination from the cells. These findings are significant to forms of macular degeneration associated with bisretinoid formation and maculopathy stemming from GSH synthase deficiency.</P>
Eum, Ki-Do,Nie, Linda H.,Schwartz, Joel,Vokonas, Pantel S.,Sparrow, David,Hu, Howard,Weisskopf, Marc G. National Institute of Environmental Health Science 2011 Environmental health perspectives Vol.119 No.7
<P>Background: No studies have examined the association between cumulative low-level lead exposure and the prospective development of electrocardiographic conduction abnormalities, which may mediate the association between lead and several cardiovascular end points.</P><P>Objective: We prospectively examined the association between lead exposure and the development of electrocardiographic conduction abnormalities.</P><P>Methods: We assessed blood lead, bone lead—a biomarker of cumulative lead exposure—measured with K-shell X-ray fluorescence, and electrocardiographic end points among 600 men in the Normative Aging Study who were free of electrocardiographic abnormalities at the time of the baseline ECG. Of these men, we had follow-up data from a second electrocardiogram for 496 men 8.1 (SD = 3.1) years later, on average. We used repeated measures linear regression to analyze change in electrocardiographic conduction timing and logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for developing specific conduction disturbances and adjusted for potential confounders.</P><P>Results: Mean (± SD) blood (5.8 ± 3.6), patella bone (30.3 ± 17.7), and tibia bone (21.6 ± 12.0) lead concentrations were similar to those found in samples from the general U.S. population and much lower than those reported in occupationally exposed groups. Compared with those in the lowest tertile of tibia lead, those in the highest had a 7.94-ms (95% CI, 1.42–14.45) increase in heart rate–corrected QT (QTc) interval and a 5.94-ms increase in heart rate–corrected QRS (95% CI, 1.66–10.22) duration > 8 years. Those in the highest tertile of tibia lead also had increased odds of QT prolongation (QTc ≥ 440 msec; OR = 2.53; 95% CI, 1.22–5.25) and JT prolongation (heart rate–corrected JT > 360 msec; OR = 2.53; 95% CI, 0.93–6.91). Results were weaker for patella lead. No associations were identified with blood lead.</P><P>Conclusions: This study suggests that low-level cumulative exposure to lead is associated with worse future cardiac conductivity in the ventricular myocardium, as reflected in QT interval characteristics.</P>