Radioactive isotope analyses of skeletal materials in forensic science: a review of uses and potential uses

A review of information that can be provided from measurements made on natural and anthropogenic radionuclide activities in human skeletal remains has been undertaken to establish what reliable information of forensic anthropological use can be obtained regarding years of birth and death (and hence post-mortem interval (PMI)). Of the anthropogenic radionuclides that have entered the environment, radiocarbon (¹⁴C) can currently be used to generate the most useful and reliable information. Measurements on single bones can indicate whether or not the person died during the nuclear era, while recent research suggests that measurements on trabecular bone may, depending on the chronological age of the remains, provide estimates of year of death and hence PMI. Additionally, ¹⁴C measurements made on different components of single teeth or on teeth formed at different times can provide estimates of year of birth to within 1–2 years of the true year. Of the other anthropogenic radionuclides, ⁹⁰Sr shows some promise but there are problems of (1) variations in activities between individuals, (2) relatively large analytical uncertainties and (3) diagenetic contamination. With respect to natural series radionuclides, it is concluded that there is no convincing evidence that ²¹⁰Pb dating can be used in a rigorous, quantitative fashion to establish a PMI. Similarly, for daughter/parent pairs such as ²¹⁰Po/²¹⁰Pb (from the ²³⁸U decay series) and ²²⁸Th/²²⁸Ra (from the ²³²Th decay series), the combination of analytical uncertainty and uncertainty in activity ratios at the point of death inevitably results in major uncertainty in any estimate of PMI. However, observation of the disequilibrium between these two daughter/parent pairs could potentially be used in a qualitative way to support other forensic evidence.     

Actions of intrathecal omega-conotoxins CVID,GVIA, MVIIA,and morphine in acute and neuropathic pain in the rat

Agents which decrease conductance of N-type voltage-gated Ca(2+) channels have been shown to attenuate measures of neuropathic pain in animal models and to provide symptom relief in humans. The omega-conotoxins have demonstrated efficacy but have a low therapeutic index. We have investigated the effects of a new omega-conotoxin, CVID (AM-336), and compared them with omega-conotoxin GVIA (SNX-124), omega-conotoxin MVIIA (SNX-111) and morphine in a spinal nerve ligation model of neuropathic pain in the rat. The ED(50) (and 95% CI) for attenuation of tactile allodynia by intrathecal administration for omega-conotoxin CVID, GVIA, MVIIA and morphine was 0.36 (0.27-0.48), 0.12 (0.06-0.24), 0.32 (0.23-0.45) and 4.4 (2.9-6.5) microg/kg, respectively. Only morphine significantly prolonged acute tail flick responses (ED(50) 2.3 (1.1-4.9) microg/kg). Of the omega-conotoxins, omega-conotoxin CVID showed the highest ratio of efficacy to behavioural toxicity. These observations show that intrathecal omega-conotoxins are effective in attenuating tactile allodynia in the rat without significantly affecting acute nociceptive responses. Omega-conotoxin CVID had similar potency to omega-conotoxin MVIIA but showed less toxicity in the therapeutic range.     

The first international consensus conference on continuous renal replacement therapy

BACKGROUND: Management of acute renal failure (ARF) in the critically ill is extremely variable and there are no published standards for the provision of renal replacement therapy in this population. We sought to review the available evidence, make evidence-based practice recommendations, and delineate key questions for future study. METHODS: We undertook an evidence-based review of the literature on continuous renal replacement therapy (CRRT) using MEDLINE searches. We determined a list of key questions and convened a 2-day consensus conference to develop summary statements via a series of alternating breakout and plenary sessions. In these sessions, we identified supporting evidence and generated practice guidelines and/or directions for future research. RESULTS: Of the 46 questions considered, we found consensus for 20. We found inadequate evidence for 21 questions and for the remaining five we found data but no consensus. Full versions of workgroup findings are available on the Internet at http://www.ADQI.net. CONCLUSIONS: Despite limited data, broad areas of consensus exist for use of CRRT and guideline development appears feasible. Equally broad areas of disagreement also exist and additional basic and applied research in acute renal failure is needed.     

Cognitive experimental approaches to investigating impaired cognition in schizophrenia: a paradigm shift

There has been a growing interest in cognitive deficits in schizophrenia in recent years. The use of traditional clinical neuropsychological measures of cognition in schizophrenia has the advantages of normative data and standardized administration, and remains the standard for cognitive assessment in clinical practice. However for the investigation of cognition in schizophrenia these methods have critical limitations in their ability to measure specific cognitive processes. In this paper we discuss solutions to these interpretive and measurement issues that can be provided by measures derived from experimental cognitive psychology. We suggest that the use of these measures will increasingly become the preferred approach to the investigation of the nature, neurobiology and genetics of impaired cognition in schizophrenia in the coming years.     

Policy implications of the gradient of health and wealth

Men in the United States with family incomes in the top 5 percent of the distribution in 1980 had about 25 percent longer to live than did those in the bottom 5 percent. Proportional increases in income are associated with equal proportional decreases in mortality throughout the income distribution. I discuss possible reasons for this gradient and ask whether it calls for the redistribution of income in the interest of public health. I argue that the existence of the gradient strengthens the case for income redistribution in favor of the poor but that targeting health inequalities would not be sound policy.