36 research outputs found
Rethinking Equality in the Global Society
The future of affirmative action, especially in the area of American higher education, has been called into question by the 1996 decision of the U.S. Court of Appeals for the Fifth Circuit in Hopwood v. State of Texas, requiring race-blind admission to state universities in Texas, and the passage of Proposition 209 in California. The seemingly endless American debate on this issue almost entirely has ignored the fact that other countries faced with comparable problems of remedying the effects of past discrimination have developed programs and acquired experience from which Americans might learn. Further, the legal debate has not been adequately informed by the social science disciplines. This conference was intended to expand discussion at a critical moment by introducing these missing perspectives
Enteric Neural Crest Differentiation in Ganglioneuromas Implicates Hedgehog Signaling in Peripheral Neuroblastic Tumor Pathogenesis
Peripheral neuroblastic tumors (PNTs) share a common origin in the sympathetic nervous system, but manifest variable differentiation and growth potential. Malignant neuroblastoma (NB) and benign ganglioneuroma (GN) stand at opposite ends of the clinical spectrum. We hypothesize that a common PNT progenitor is driven to variable differentiation by specific developmental signaling pathways. To elucidate developmental pathways that direct PNTs along the differentiation spectrum, we compared the expression of genes related to neural crest development in GN and NB. In GNs, we found relatively low expression of sympathetic markers including adrenergic biosynthesis enzymes, indicating divergence from sympathetic fate. In contrast, GNs expressed relatively high levels of enteric neuropeptides and key constituents of the Hedgehog (HH) signaling pathway, including Dhh, Gli1 and Gli3. Predicted HH targets were also differentially expressed in GN, consistent with transcriptional response to HH signaling. These findings indicate that HH signaling is specifically active in GN. Together with the known role of HH activity in enteric neural development, these findings further suggested a role for HH activity in directing PNTs away from the sympathetic lineage toward a benign GN phenotype resembling enteric ganglia. We tested the potential for HH signaling to advance differentiation in PNTs by transducing NB cell lines with Gli1 and determining phenotypic and transcriptional response. Gli1 inhibited proliferation of NB cells, and induced a pattern of gene expression that resembled the differential pattern of gene expression of GN, compared to NB (p<0.00001). Moreover, the transcriptional response of SY5Y cells to Gli1 transduction closely resembled the transcriptional response to the differentiation agent retinoic acid (p<0.00001). Notably, Gli1 did not induce N-MYC expression in neuroblastoma cells, but strongly induced RET, a known mediator of RA effect. The decrease in NB cell proliferation induced by Gli1, and the similarity in the patterns of gene expression induced by Gli1 and by RA, corroborated by closely matched gene sets in GN tumors, all support a model in which HH signaling suppresses PNT growth by promoting differentiation along alternative neural crest pathways
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Pioneers in AIDS care : reflections on the epidemic's early years
In 1995, Constance Wofsy, who had been a leader in San Francisco's response to AIDS in the 1980s, recalled the way she and other physicians had been drawn to the nascent epidemic. “How gripped we were,” she said, “How separate we were from everyone who wasn't part of the thing. There were the involved and uninvolved, and they just didn't understand one another.” In July, a tape recording of these recollections, made a year before Wofsy's death, was heard by 17 doctors who had come together in New York to commemorate the 25th anniversary of the first reported AIDS cases. The participants were among 76 first-generation AIDS doctors whom we had interviewed in the 1990s for an oral history documenting the U.S. epidemic.1 At the day-long July meeting, they looked back on their work, shared memories of the darkest years, recalled the exhilaration of the first prospects for effective AIDS treatment, and ruminated about who would step in to care for future patients
Becoming the Framingham Study 1947–1950
In the epidemiological imagination, the Framingham Heart Study has attained iconic status, both as the prototype of the cohort study and as a result of its scientific success. When the Public Health Service launched the study in 1947, epidemiological knowledge of coronary heart disease was poor, and epidemiology primarily involved the study of infectious disease. In constructing their investigation, Framingham’s initiators had to invent new approaches to epidemiological research. These scientific goals were heavily influenced by the contending institutional and personal interests buffeting the study. The study passed through vicissitudes and stages during its earliest years as its organizers grappled to define its relationship to medicine, epidemiology, and the local community