14 research outputs found
Design, recruitment, and retention of African-American smokers in a pharmacokinetic study
<p>Abstract</p> <p>Background</p> <p>African-Americans remain underrepresented in clinical research despite experiencing a higher burden of disease compared to all other ethnic groups in the United States. The purpose of this article is to describe the study design and discuss strategies used to recruit and retain African-American smokers in a pharmacokinetic study.</p> <p>Methods</p> <p>The parent study was designed to evaluate the differences in the steady-state concentrations of bupropion and its three principal metabolites between African-American menthol and non-menthol cigarette smokers. Study participation consisted of four visits at a General Clinical Research Center (GCRC) over six weeks. After meeting telephone eligibility requirements, phone-eligible participants underwent additional screening during the first two GCRC visits. The last two visits (pharmacokinetic study phase) required repeated blood draws using an intravenous catheter over the course of 12 hours.</p> <p>Results</p> <p>Five hundred and fifteen African-American smokers completed telephone screening; 187 were phone-eligible and 92 were scheduled for the first GCRC visit. Of the 81 who attended the first visit, 48 individuals were enrolled in the pharmacokinetic study, and a total of 40 individuals completed the study (83% retention rate).</p> <p>Conclusions</p> <p>Although recruitment of African-American smokers into a non-treatment, pharmacokinetic study poses challenges, retention is feasible. The results provide valuable information for investigators embarking on non-treatment laboratory-based studies among minority populations.</p
Simultaneous Low- and High-Grade Primary Leiomyosarcomas in Two Separate Organs in a Thirty-Year Survivor of Hereditary Retinoblastoma
Patients with hereditary retinoblastoma have a heightened risk of developing subsequent bone and soft tissue sarcomas, exacerbated by radiation and alkylating chemotherapy. Secondary leiomyosarcomas are rare. A 29-year-old patient with bilateral retinoblastoma history presented with concurrent, independent malignancies found to be Rb-suppressed uterine and Rb-positive bladder leiomyosarcomas. She had undergone both ifosfamide chemotherapy and radiation therapy but demonstrated rare simultaneous primary leiomyosarcomas not previously described in association with ifosfamide. This rare case underlines the protean genetic predisposition to malignancy in this patient population, heightening awareness of lifelong malignancy potential, and the necessity for continuous periodic screening
<i>In vivo</i> induction of massive proliferation, directed migration, and differentiation of neural cells in the adult mammalian brain
The development of an
in vivo
procedure for the
induction of massive proliferation, directed migration, and
neurodifferentiation (PMD) in the damaged adult central nervous system
would hold promise for the treatment of human neurodegenerative
disorders such as Parkinson's disease. We investigated the
in
vivo
induction of PMD in the forebrain of the adult rat by
using a combination of 6-hydroxydopamine lesion of the substantia nigra
dopaminergic neurons and infusions of transforming growth factor α
(TGFα) into forebrain structures. Only in animals with both lesion
and infusion of TGFα was there a rapid proliferation of forebrain
stem cells followed by a timed migration of a ridge of neuronal and
glial progenitors directed toward the region of the TGFα infusion
site. Subsequently, increasing numbers of differentiated neurons were
observed in the striatum. In behavioral experiments, there was a
significant reduction of apomorphine-induced rotations in animals
receiving the TGFα infusions. These results show that the brain
contains stem cells capable of PMD in response to an exogenously
administered growth factor. This finding has significant implications
with respect to the development of treatments for both acute neural
trauma and neurodegenerative diseases.
</jats:p
