Cellular therapies for treating pain associated with spinal cord injury

Spinal cord injury leads to immense disability and loss of quality of life in human with no satisfactory clinical cure. Cell-based or cell-related therapies have emerged as promising therapeutic potentials both in regeneration of spinal cord and mitigation of neuropathic pain due to spinal cord injury. This article reviews the various options and their latest developments with an update on their therapeutic potentials and clinical trialing

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Voltammetric studies of the catalytic mechanism of the respiratory nitrate reductase from Escherichia coli: how nitrate reduction and inhibition depend on the oxidation state of the active site.

The respiratory molybdoenzyme nitrate reductase (NarGHI) from Escherichia coli has been studied by protein film voltammetry, with the enzyme adsorbed on a rotating disk pyrolytic graphite edge (PGE) electrode. Catalytic voltammograms for nitrate reduction show a complex wave consisting of two components that vary with pH, nitrate concentration, and the presence of inhibitors. At micromolar levels of nitrate, the activity reaches a maximum value at approximately -25 mV and then decreases as the potential becomes more negative. As the nitrate concentration is raised, the activity at more negative potentials increases and eventually becomes the dominant feature at millimolar concentrations. This leads to the hypothesis that nitrate binds more tightly to Mo(V) than Mo(IV), so that low levels of nitrate are more effectively reduced at a higher potential despite the lower driving force. However, an alternative interpretation, that nitrate binding is affected by a change in the redox state of the pterin, cannot be ruled out. This proposal, implicating a specific redox transition at the active site, is supported by experiments carried out using the inhibitors azide and thiocyanate. Azide is the stronger inhibitor of the two, and each inhibitor shows two inhibition constants, one at high potential and one at low potential, both of which are fully competitive with nitrate; closer analysis reveals that the inhibitors act preferentially upon the catalytic activity at high potential. The unusual potential dependence therefore derives from the weaker binding of nitrate or the inhibitors to a more reduced state of the active site. The possible manifestation of these characteristics in vivo has interesting implications for the bioenergetics of E. coli

Medical Information on the Internet: A Study of an Electronic Bulletin Board

OBJECTIVE: To assess medical information provided in a medically oriented Internet discussion group, in terms of the professional status of the individuals providing information, the consistency of the information with standard medical practice, and the nature of the evidence cited in support of specific claims or recommendations. DESIGN: Standardized review of 1,658 consecutive messages on a particular online discussion group during a 5-month period. SETTING: An online discussion group for sufferers of painful hand and arm conditions. SUBJECTS: All participants in this discussion group during the study period. MEASUREMENTS AND MAIN RESULTS: Professional training of those offering medical information, consistency of the advice and recommendations offered with conventional medical practice, and nature of evidence cited in support of medical claims were determined. Of all messages, 55.9% (927) addressed a medical topic. Of these, 79% (732) provided medical information, of which 89.3% (654) were authored by persons without professional medical training, and 5.1% (37) were authored by trained health professionals. Approximately one third of the medical information provided was classified as unconventional. Personal experience was the basis of information provided in 61% of the nonprofessionals’ messages and 13.5% of the professionals’ messages, while no source was given as the basis of information provided in 29.8% of the nonprofessionals’ messages and 67.6% of the professionals’ messages. A published source was cited in 9.2% of the nonprofessionals’ and 18.9% of the professionals’ messages. CONCLUSIONS: These findings suggest that medical information available on Internet discussion groups may come from nonprofessionals and may be unconventional, based on limited evidence, and/or inappropriate