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1.
Water Secur ; 2: 1-10, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29532811

RESUMEN

Household water insecurity has serious implications for the health, livelihoods and wellbeing of people around the world. Existing methods to assess the state of household water insecurity focus largely on water quality, quantity or adequacy, source or reliability, and affordability. These methods have significant advantages in terms of their simplicity and comparability, but are widely recognized to oversimplify and underestimate the global burden of household water insecurity. In contrast, a broader definition of household water insecurity should include entitlements and human capabilities, sociocultural dynamics, and political institutions and processes. This paper proposes a mix of qualitative and quantitative methods that can be widely adopted across cultural, geographic, and demographic contexts to assess hard-to-measure dimensions of household water insecurity. In doing so, it critically evaluates existing methods for assessing household water insecurity and suggests ways in which methodological innovations advance a broader definition of household water insecurity.

2.
Hist Sci ; 54(4): 443-459, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28027704

RESUMEN

Over the last half century, a multijurisdictional, multiscale system of governance has emerged to address concerns associated with toxic chemicals that have the capacity to bioaccumulate in organisms and biomagnify in food chains, leading to fish consumption advisories. Components of this system of governance include international conventions (such as the Stockholm Convention on Persistent Organic Pollutants and the Minamata Convention on Mercury), laws enacted by nation states and their subjurisdictions, and efforts to adaptively manage regional ecosystems (such as the U.S.-Canadian Great Lakes). Given that many of these compounds - including mercury, industrial chemicals such as polychlorinated biphenyls, and pesticides such as toxaphene - circulate throughout the globe through cycles of deposition and reemission, regional efforts to eliminate the need for fish consumption advisories cannot be successful without efforts to reduce emissions everywhere in the world. This paper argues that the scientific community, by monitoring the concentrations of these compounds in the atmosphere and by modeling their fate and transport, play an important role in connecting the various jurisdictional scales of governance. In addition, the monitoring networks that this community of scientists has established can be visualized as a technology of governance essential in an era in which societies have the capacity to produce and release such chemicals on an industrial scale.

4.
Eur J Med Chem ; 44(7): 2944-51, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19121874

RESUMEN

Four ester prodrugs derived from the bifunctional alkylating agent chlorambucil, and one of its nitro-derivatives, 3-nitrochlorambucil conjugated to prasterone and pregnenolone, were synthesized and tested for their cytotoxic activity against eight human cell lines, using the standard MTT assay. A comparison between the esters and the controls, namely chlorambucil and 3-nitrochlorambucil would suggest that all four esters possess to varying degrees, specificity towards the breast adenocarcinoma cell line (MDA-mb468) than the other seven cells' lines tested. The overall findings are encouraging since it infers that these lipophilic esters not only have the ability to traverse specific cell membranes but also exhibit cytotoxicity towards most of the cell lines tested.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Clorambucilo/análogos & derivados , Clorambucilo/farmacología , Deshidroepiandrosterona/química , Nitrocompuestos/química , Pregnenolona/química , Animales , Antineoplásicos/síntesis química , Línea Celular Tumoral , Clorambucilo/síntesis química , Cromatografía Líquida de Alta Presión , Ésteres/síntesis química , Ésteres/química , Ésteres/farmacología , Humanos , Concentración 50 Inhibidora , Neoplasias/patología
5.
J Neurosci ; 27(5): 1190-9, 2007 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-17267575

RESUMEN

The subpopulation of dorsal root ganglion (DRG) neurons recognized by Griffonia simplicifolia isolectin B4 (IB4) differ from other neurons by expressing receptors for glial cell line-derived neurotrophic factor (GDNF) rather than neurotrophins. Additionally, IB4-labeled neurons do not express the laminin receptor, alpha7-integrin (Gardiner et al., 2005), necessary for optimal axonal regeneration in the peripheral nervous system. In cultures of dissociated DRG neurons of adult mice on laminin, robust spontaneous neurite outgrowth from IB4-negative neurons occurs and is strongly enhanced by previous axotomy. In contrast, IB4-labeled neurons show little neurite outgrowth and do not express GAP 43, even after axotomy or culture with GDNF. Moreover, growth of their axons through collagen gels is impaired compared with other DRG neurons. To determine whether the sparse neurite outgrowth of IB4-labeled neurons is attributable to lack of integrin expression, DRG cultures were infected with a herpes simplex 1 vector encoding alpha7-integrin, but its forced expression failed to promote neurite outgrowth in either IB4-labeled or other DRG neurons or in cultured adult retinal ganglion cells. Forced coexpression of both alpha7-integrin and GAP 43 also failed to promote neurite outgrowth in IB4-labeled neurons. In addition, cultured sciatic nerve segments were found to release much lower levels of GDNF, demonstrated by ELISA, than nerve growth factor. These findings together with their impaired intrinsic axonal regeneration capacity may contribute to the known vulnerability of the IB4-labeled population of DRG neurons to peripheral nerve injury.


Asunto(s)
Axones/metabolismo , Ganglios Espinales/metabolismo , Regeneración Nerviosa/fisiología , Neuronas/metabolismo , Lectinas de Plantas/metabolismo , Animales , Axones/química , Axones/clasificación , Células COS , Línea Celular , Células Cultivadas , Chlorocebus aethiops , Cricetinae , Femenino , Ganglios Espinales/química , Ganglios Espinales/crecimiento & desarrollo , Griffonia , Humanos , Ratones , Neuronas/química , Neuronas/clasificación , Unión Proteica/fisiología , Ratas
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