Pain
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Pathological pain is one of the most common neurological complications in patients with HIV-1/AIDS. However, the pathogenic process is unclear. Our recent studies show that Wnt5a is upregulated in the spinal cord dorsal horn (SDH) of the patients with HIV who develop pain and that HIV-1 gp120, a potential causal factor of the HIV-associated pain, rapidly upregulates Wnt5a in the mouse SDH. ⋯ Furthermore, while Foxy5 potentiated spike frequency of SDH neurons, either SP600125 or Enbrel blocked the potentiation. The data indicate that Wnt5a potentiates the activity of SDH neurons through the JNK-TNF-α pathway. Collectively, our findings suggest that Wnt5a regulates the pathogenesis of gp120-induced pain, likely by sensitizing pain-processing SDH neurons through JNK/TNF-α signaling.
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Neuropathic pain is a chronic pain syndrome that arises from nerve injury. Current treatments only offer limited relief, clearly indicating the need for more effective therapeutic strategies. Previously, we demonstrated that proinflammatory tumor necrosis factor-alpha (TNF) is a key mediator of neuropathic pain pathogenesis; TNF is elevated at sites of neuronal injury, in the spinal cord, and supraspinally during the initial development of pain. ⋯ TNF levels (bioactive protein, TNF immunoreactivity) in hippocampal tissue were decreased. The observation that TNF nanoplex injection into the hippocampus alleviated neuropathic pain-like behavior advances our previous findings that hippocampal TNF levels modulate pain perception. These data provide evidence that targeting TNF in the brain using nanoparticle-protected siRNA may be an effective strategy for treatment of neuropathic pain.
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To estimate the prevalence of problem opioid use, we used natural language processing (NLP) techniques to identify clinical notes containing text indicating problem opioid use from over 8 million electronic health records (EHRs) of 22,142 adult patients receiving chronic opioid therapy (COT) within Group Health clinics from 2006 to 2012. Computer-assisted manual review of NLP-identified clinical notes was then used to identify patients with problem opioid use (overuse, misuse, or abuse) according to the study criteria. These methods identified 9.4% of patients receiving COT as having problem opioid use documented during the study period. ⋯ Higher rates of problem opioid use were observed among young COT patients, patients who sustained opioid use for more than 4 quarters, and patients who received higher opioid doses. Methods used in this study provide a promising approach to efficiently identify clinically recognized problem opioid use documented in EHRs of large patient populations. Computer-assisted manual review of EHR clinical notes found a rate of problem opioid use of 9.4% among 22,142 COT patients over 7 years.
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Randomized Controlled Trial Multicenter Study
Development and Preliminary Validation of an Integrated Efficacy-Tolerability Composite Measure for the Evaluation of Analgesics.
The goal of this analysis was to develop and evaluate integrated measures of benefit and tolerability of analgesic drugs in clinical trials. We evaluated an efficacy-tolerability composite (ETC) measure combining different cutoff values for daily pain reduction (≥20%, ≥30%, or ≥50% pain reduction) and adverse events (AEs) (no AE, no or mild AEs, no or mild drug-related AEs). Nine ETC cutoff values (3 × 3) were tested using data from a randomized double-blind trial comparing tapentadol extended release (ER) (n = 310), oxycodone controlled release (CR) (n = 322), and placebo (n = 314) in subjects with chronic low back pain. ⋯ For all 9 ETC measures, validity was demonstrated by significant correlation of ETC scores with patients' Global Impression of change and with change from baseline in pain scores. Tapentadol ER ETC scores were statistically significantly higher than oxycodone CR ETC scores for 4 of the ETC measures. "No/mild drug-related AE and ≥20% pain reduction" demonstrated the best overall validity (correlation with patients' global impression of change) and responsiveness (discrimination between treatment groups), yielding a higher standardized effect size for tapentadol ER compared with placebo (0.19 [95% confidence interval: 0.031-0.346]) and with oxycodone CR (0.23 [95% confidence interval: 0.070-0.383]) than other cutoff values. Thus, we have identified herein a composite measure that seems to be a valid and responsive measure of the overall efficacy and tolerability of analgesics in clinical trials.