The Global Task Force for Chronic Pain in People with HIV (PWH): Developing a research agenda in an emerging field

Chronic pain is a common comorbidity in people with HIV (PWH), with prevalence estimates of 25-85%. Research in this area is growing, but significant gaps remain. A Global Task Force of HIV experts was organized to brainstorm a scientific agenda and identify measurement domains critical to advancing research in this field. Experts were identified through literature searches and snowball sampling. Two online questionnaires were developed by Task Force members. Questionnaire 1 asked participants to identify knowledge gaps in the field of HIV and chronic pain and identify measurement domains in studies of chronic pain in PWH. Responses were ranked in order of importance in Questionnaire 2, which was followed by a group discussion. 29 experts completed Questionnaire 1, 25 completed Questionnaire 2, and 21 participated in the group. Many important clinical and research priorities emerged, including the need to examine etiologies of chronic pain in PWH. Pain-related measurement domains were discussed, with a primary focus on domains that could be assessed in a standardized manner across various cohorts that include PWH in different countries. We collaboratively identified clinical and research priorities, as well as gaps in standardization of measurement domains, that can be used to move the field forward.

The role of psychological flexibility in relation to suicidal thinking in chronic pain

BACKGROUND

Suicidal thinking (ST) is common in people with chronic pain. It is relevant as it can be associated with suicidal attempts, and typically reflects significant suffering. While little is known about the psychological processes that contribute to ST, current psychological models, such as the Psychological Flexibility (PF) model, could help guide further investigation. This study investigates relations between ST and components of PF in chronic pain.

METHODS

Participants were 424 adults attending treatment for chronic pain in the UK. Included in measures administered before treatment were standardized measures of depression, pain, pain-related interference, and measures of PF, including acceptance, cognitive defusion, committed action, and self-as-context. An item from the measure of depression was used to reflect ST.

RESULTS

A large proportion of the sample reported ST, 45.7%. ST was uncorrelated with participant background characteristic, medications taken, or pain intensity. However, it was correlated with the presence of widespread pain, pain-related interference, and depression. Each component of PF was found to be significantly negatively associated with ST, as predicted. General acceptance correlated with ST at a level equal to that achieved by the depression score. In adjusted multivariate logistic regression general acceptance and committed action remained significantly uniquely associated with it.

CONCLUSION

This preliminary study suggests for the first time that components of PF are associated with part of a pattern of suicidal behaviour in people with chronic pain. They may be relevant for reducing avoidance in general and providing more positive behavioural options.

SIGNIFICANCE

This study provides evidence that components of psychological flexibility are associated with a reduced frequency of suicidal thinking in people with chronic pain. Treatments targeting psychological flexibility may help mitigate the impact of chronic pain on suicidal thinking.

Feasibility randomized-controlled trial of online Acceptance and Commitment Therapy for patients with complex chronic pain in the United Kingdom

BACKGROUND

Acceptance and Commitment Therapy (ACT) has growing support for chronic pain. However, more accessible treatment delivery is needed. This study evaluated the feasibility of online ACT for patients with complex chronic pain in the United Kingdom to determine whether a larger trial is justified.

METHODS

Participants with chronic pain and clinically meaningful disability and distress were randomly assigned to ACT online plus specialty medical pain management, or specialty medical management alone. Participants completed questionnaires at baseline, and 3- and 9-month post-randomization. Primary feasibility outcomes included recruitment, retention and treatment completion rates. Secondary outcomes were between-groups effects on treatment outcomes and psychological flexibility.

RESULTS

Of 139 potential participants, 63 were eligible and randomized (45% recruitment rate). Retention rates were 76-78% for follow-up assessments. Sixty-one per cent of ACT online participants completed treatment. ACT online was less often completed by employed (44%) compared to unemployed (80%) participants. Fifty-six per cent of ACT online participants rated themselves as 'much improved' or better on a global impression of change rating, compared to only 20 per cent of control participants. Three-month effects favouring ACT online were small for functioning, medication and healthcare use, committed action and decentring, medium for mood, and large for acceptance. Small-to-medium effects were maintained for functioning, healthcare use and committed action at 9 months.

CONCLUSIONS

Online ACT for patients with chronic pain in the United Kingdom appears feasible to study in a larger efficacy trial. Some adjustments to treatment and trial procedures are warranted, particularly to enhance engagement among employed participants.

SIGNIFICANCE

This study supports the feasibility of online Acceptance and Commitment Therapy for chronic pain in the United Kingdom and a larger efficacy trial. Refinements to treatment delivery, particularly to better engage employed patients, may improve treatment completion and outcomes.

Effect of fat additions to diets of dairy cattle on milk production and components: a meta-analysis and meta-regression

The objectives of this study were to critically review randomized controlled trials, and quantify, using meta-analysis and meta-regression, the effects of supplementation with fats on milk production and components by dairy cows. We reviewed 59 papers, of which 38 (containing 86 comparisons) met eligibility criteria. Five groups of fats were evaluated: tallows, calcium salts of palm fat (Megalac, Church and Dwight Co. Inc., Princeton, NJ), oilseeds, prilled fat, and other calcium salts. Milk production responses to fats were significant, and the estimated mean difference was 1.05 kg/cow per day, but results were heterogeneous. Milk yield increased with increased difference in dry matter intake (DMI) between treatment and control groups, decreased with predicted metabolizable energy (ME) balance between these groups, and decreased with increased difference in soluble protein percentage of the diet between groups. Decreases in DMI were significant for Megalac, oilseeds, and other Ca salts, and approached significance for tallow. Feeding fat for a longer period increased DMI, as did greater differences in the amount of soluble protein percentage of the diet between control and treatment diets. Tallow, oilseeds, and other Ca salts reduced, whereas Megalac increased, milk fat percentage. Milk fat percentage effects were heterogeneous for fat source. Differences between treatment and control groups in duodenal concentrations of C18:2 and C 18:0 fatty acids and Mg percentage reduced the milk fat percentage standardized mean difference. Milk fat yield responses to fat treatments were very variable. The other Ca salts substantially decrease, and the Megalac and oilseeds increased, fat yield. Fat yield increased with increased DMI difference between groups and was lower with an increased estimated ME balance between treatment and control groups, indicating increased partitioning of fat to body tissue reserves. Feeding fats decreased milk protein percentage, but results were heterogeneous. An increased number of milkings increased the milk protein percentage, whereas the difference between the treatment and control groups in duodenal concentrations of 18:2 fatty acids and dietary Mg concentration reduced the milk protein percentage. None of the fat treatments influenced milk protein production. The range of responses to different fats fed approached or exceeded 5 standard deviations from the mean and differed in point direction for all variables studied, indicating the varied and profound biological effects of fats. Responses to fat feeding were highly heterogeneous for all variables studied and heterogeneity was present within responses to individual fat groups. The lower DMI combined with higher milk and milk fat production showed that fats could improve the efficiency of milk production. More studies are required to more completely characterize sources of variation in responses to fats.

Antisense inhibition of S6 kinase 1 produces improved glucose tolerance and is well tolerated for 4 weeks of treatment in rats

p70 Ribosomal S6 kinase 1 (S6K1) is implicated in the pathogenesis of type 2 diabetes as knockout mice are hypoinsulinemic, hypersensitive to insulin treatment and are less susceptible to obesity-induced insulin resistance. Although S6K1 knockout mice provide important information on the biology of this target, the therapeutic relevance of S6K1 inhibition in adult animals is unknown. Thus, this research evaluated the potential safety and efficacy of S6K1 inhibition using antisense oligonucleotides (ASO) in mature Sprague-Dawley rats. Male rats treated with S6K1 ASO (25 or 50 mg/kg, 2×/week × 4 weeks) had a marked reduction (>90%) of S6K1 mRNA in the liver and epididymal fat and no effect on hepatic S6K2 expression. The decrease in S6K1 mRNA translated to decreased (>80%) S6K1 protein and kinase activity in the liver at the 50-mg/kg dose. The animals tolerated the S6K1 treatment well with no signs of clinical toxicity. A reduction in body weight gain was observed within 2 weeks of S6K1 ASO treatment. At 4 weeks, body weight gain was reduced by up to 25% in the 50 mg/kg group with a commensurate decrease (14%) in food consumption. A decrease in heart weight in the 50 mg/kg group was observed and not associated with cardiac injury or dysfunction. In an oral glucose tolerance test, S6K1-ASO-treated animals demonstrated a dose-dependent improvement in systemic glucose utilization and had reduced fasting insulin levels. Hepatic gene microarray analysis identified dose-dependent elevations in igfbp1, acss2 and acat2 gene expression in S6K1-ASO-treated animals. These results suggest that inhibition of S6K1 for up to 4 weeks may be therapeutically relevant to induce insulin sensitization and attenuate weight gain with low risk for serious toxicity.

PET response following stereotactic body radiotherapy for non-small cell lung carcinoma correlates with local control

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Background: Given the success of Stereotactic Body Radiotherapy (SBRT) for Non-Small Cell Lung Carcinoma (NSCLC), early surrogates of local failure (LF) are necessary to allow timely surgical salvage. This study tries to determine the utility of PET response as an early surrogate for LF. Methods: Eligible patients(pts) had biopsy proven NSCLC < 5 cm in size who underwent a pre- and post- SBRT PET scans. Pts treated at Fox Chase Cancer Center were either: 1. early stage (10 pts), 2. biopsy-proven local recurrences (4 patients) or 3. oligometastases (3 patients). Eleven of the 17 pts were treated on a prospective phase I dose escalation protocol and received either 40 Gy or 48 Gy in 4 fractions over 8 days. Non-protocol pts generally received 48 Gy in 4 fractions (5 of 6 pts). Treatment volumes were individualized for each pt using either 4 D or multi-phase CT simulation. As part of the prospective study design, PETs scan was obtained pre- and post-SBRT to correlate metabolic response with LF based on the work by MacManus. The post-SBRT PET scan was obtained at a median of 3 months following treatment (range, 2 to 6 months). LF was defined by my an increase in size on CT on serial imaging. Results: With a median follow up of 14 months (range 4 to 31 months), 3 LF have been documented. The median SUV max pre-SBRT was 4.7 (range 1.32 to 18.2) and 1.9 (range 0.9 to 7.0) post-SBRT. Only four pts had a post-SBRT SUV max > 2.5 (2.8, 5.1, 5.3 and 7). Overall, twelve pts had a drop in their SUV max following SBRT, while 1 pt had stabilization and 4 had an increase . Of these last 5 pts, 3 developed LF. The other two have been followed without any intervention and remain free of recurrence for > 2 years, respectively. No pt with an initial drop in post SBRT PET scan SUV has had LF. Conclusions: PET response (defined as a drop in the SUV max by 3 months) correlates with LF, and appears to be a good early surrogate of outcomes following SBRT. Larger studies are required to confirm this finding.

No significant financial relationships to disclose.

Touch prep (TP) cytology as a tool for determining pulmonary parenchymal resection margin status

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Background: Accurate determination of parenchymal resection margins is critical in excision of primary and metastatic lung cancers. Complete microscopic examination of the entire margin is difficult and may not give timely results. Staple-line excision may compromise the accuracy of histologic margin exam (HME). TP offers a novel method to obtain pulmonary parenchymal margin status intraoperatively. Methods: Patients undergoing wedge resection for a known malignant lung lesion were studied prospectively. At the time of resection, the specimen stapled margin underwent TP on 3 glass slides for cytological analysis. The presence or absence of malignant cells on TP was correlated to final HME. Local recurrence and overall survival by TP and HME status were compared using logrank test. Results: Thirty specimens from 29 patients were studied between December 2002 and April 2006. Fifteen specimens (50%) were right- sided; 9/29 patients (31%) were male. Median age was 66 years (range 28 - 81). Histologies included non-small cell lung cancer (NSCLC) in 22 (73%), and metastases from colorectal cancer (4/30, 13%), sarcoma (2/20, 7%), and breast (1/30, 3%). All TP negative specimens had negative HME. TP was positive in 10 of 30 (33%) specimens, 6 of which had negative HME. These included 4 NSCLC and metastases from sarcoma (1) and colon (1). Mean margin distance was 4 ± 1.7 mm for TP/HME negative specimens, 0.5 ± 0 mm for TP/HME positive specimens, and 5 ± 1.7 mm for TP positive/HME negative patients. There was no difference in time to local recurrence between patients with positive margins by TP vs HME (18.6 and 18.63 months), or in TP and HME negative patients (30.1 and 30.6 months). Conclusion: TP analysis of lung parenchymal margins is safe and feasible. A negative TP is highly predictive of negative HME. Factors contributing to false-positive TP remain unresolved. Multi-institutional prospective studies are indicated for further characterization of this promising tool.

No significant financial relationships to disclose.

Incidence and behaviour of Tn916-like elements within tetracycline-resistant bacteria isolated from root canals

INTRODUCTION

Tetracycline resistance is commonly found in endodontic bacteria. One of the most common tetracycline-resistance genes is tet(M), which is often encoded on the broad-host-range conjugative transposon Tn916. This study aimed to determine whether tet(M) was present in bacteria isolated from endodontic patients at the Eastman Dental Institute and whether this gene was carried on the transferable conjugative transposon Tn916.

METHODS

The cultivable microflora isolated from 15 endodontic patients was screened for resistance to tetracycline. Polymerase chain reactions for tet(M) and for unique regions of Tn916 were carried out on the DNA of all tetracycline-resistant bacteria. Filter-mating experiments were used to see if transfer of any Tn916-like elements could occur.

RESULTS

Eight out of 15 tetracycline-resistant bacteria isolated were shown to possess tet(M). Furthermore, four of these eight were shown to possess the Tn916-unique regions linked to the tet(M) gene. Transfer experiments demonstrated that a Neisseria sp. donor could transfer an extremely unstable Tn916-like element to Enterococcus faecalis.

CONCLUSIONS

The tet(M) gene is present in the majority of tetracycline-resistant bacteria isolated in this study and the conjugative transposon Tn916 has been shown to be responsible for the support and transfer of this gene in some of the bacteria isolated.

Simulation and clinical practice: strengthening the relationship

INTRODUCTION

This discussion paper argues for a creative synthesis between simulation and clinical practice, where an iterative process of continual interaction ensures that skills are learned and reinforced within the context of everyday professional life.

BACKGROUND

Evidence is mounting that long-established approaches to surgical training are no longer acceptable in the current ethical and professional climate. This paper considers alternatives to the traditional approach of 'learning by doing' in a clinical context, focusing on recent developments in the technology of simulation and virtual reality. Clinical expertise is a complex phenomenon and no single theory can account for its acquisition. After a brief contextualising overview, Vygotsky's 'zone of proximal development' is proposed as a conceptual framework for task-based surgical learning that takes place within skills laboratories. The discussion is located within a wider context of educational theory, drawing on current thinking about situated learning and apprenticeship. The notion of 'legitimate peripheral participation' in a complex professional environment places technical skill alongside a range of other competencies that are necessary to safe practice.

CONCLUSIONS

Simulation offers a safe environment within which learners can repeatedly practise a range of clinical skills without endangering patients. Comprehensive simulated environments allow a move away from isolated tasks to more complex clinical situations, recreating many of the challenges of real life. Such simulations, however, can operate in isolation from their clinical context, ignoring the learning needs of individuals within a real health care environment. To realise its full potential as a learning aid, simulation must be used alongside clinical practice and linked closely with it.

Targeted disruption of the Nhe1 gene fails to inhibit beta(1)-adrenergic receptor-induced parotid gland hypertrophy

Chronic beta(1)-adrenergic receptor activation results in hypertrophy and hyperplasia of rodent salivary gland acinar cells. Na(+)/H(+) exchanger isoform 1 (NHE1) regulates cell volume and the induction of cell proliferation in many tissues. To investigate the relationship between NHE1 and the response of parotid glands to beta(1)-adrenergic agonists, we examined by Northern blot analysis NHE1 expression in saline-treated mice and mice 30 min and 2, 6, and 24 h after isoproterenol injection. NHE1 transcripts increased approximately 50% by 2 h, and a more than twofold increase was noted at 24 h. Isoproterenol did not acutely increase Na(+)/H(+) exchanger activity; however, exchanger activity was significantly elevated by 24 h. To test whether NHE1 activity is essential for inducing salivary gland hypertrophy in vivo, mice with targeted disruption of Nhe1 were treated with isoproterenol. Na(+)/H(+) exchanger activity was absent in acinar cells from Nhe1(-/-) mice, nevertheless, the lack of NHE1 failed to inhibit isoproterenol-induced hypertrophy. These data directly demonstrate that acinar cell hypertrophy induced by chronic beta(1)-adrenergic receptor stimulation occurs independently of NHE1 activity.

Hyperoxia inhibits oxidant-induced apoptosis in lung epithelial cells

It has previously been shown that hyperoxia induces nonapoptotic cell death in cultured lung epithelial cells, whereas hydrogen peroxide (H(2)O(2)) and paraquat cause apoptosis. To test whether pathways leading to oxidative apoptosis in epithelial cells are sensitive to molecular O(2), A549 cells were exposed to 95% O(2) prior to exposure to lethal concentrations of H(2)O(2). The extent of H(2)O(2)-induced apoptosis was significantly reduced in cells preexposed to hyperoxia compared with room-air controls. Preexposure of the hyperoxia-resistant HeLa-80 cell line to 80% O(2) also inhibited oxidant-induced apoptosis, suggesting that this inhibition is not due to O(2) toxicity. Because hyperoxia generates reactive oxygen species and activates the redox-sensitive transcription factor nuclear factor kappa B (NF-kappa B), the role of antioxidant enzymes and NF-kappa B were examined in this inhibitory process. The onset of inhibition appeared to be directly related to the degradation of I kappa B and subsequent activation of NF-kappa B (either by hyperoxia or TNF-alpha), whereas no significant up-regulation of endogenous antioxidant enzyme activities was found. In addition, suppression of NF-kappa B activities by transfecting A549 cells with a dominant-negative mutant construct of I kappa B significantly augmented the extent of H(2)O(2)-induced apoptosis. These data suggest that hyperoxia inhibits oxidant-induced apoptosis and that this inhibition is mediated by NF-kappa B.

Esmolol versus diltiazem in the treatment of postoperative atrial fibrillation/atrial flutter after open heart surgery

BACKGROUND

Supraventricular tachyarrhythmias are common after open heart surgery. Possible causative factors for these arrhythmias include operative trauma, atrial ischemia, electrolyte imbalances, pericardial irritation, and excess catecholamines. Two agents commonly used to control ventricular rate in atrial fibrillation or atrial flutter (AF/AFL) are beta-blockers and calcium channel blockers.

METHODS AND RESULTS

This randomized study was designed to compare the safety and efficacy of intravenous diltiazem versus intravenous esmolol in patients with postoperative AF/AFL after coronary bypass surgery and/or valve replacement surgery. A comparative cost analysis was also performed. Thirty patients received either esmolol (n = 15) or diltiazem (n = 15) for AF/AFL. During the first 6 hours of treatment, 66.6% of esmolol-treated patients converted to sinus rhythm compared with 13.3% of the diltiazem-treated patients (P <.05). At 24 hours, 66.6% of the diltiazem group converted to SR compared with 80% of the esmolol group (not significant). Drug-induced side effects, time to rate control (<90 beats/min), number of patients requiring cardioversion, and length of hospitalization were similar for the two groups. The drug cost/successfully treated patient for esmolol versus diltiazem was $254 versus $437 at 6 hours and $529 versus $262 at 24 hours.

CONCLUSIONS

Although this is a small study, it suggests that esmolol is more effective in converting patients to normal sinus rhythm than diltiazem during the initial dosing period. No differences in conversion rates were observed between the two groups after 24 hours. Additional studies are needed to confirm whether esmolol is the initial drug of choice in patients with postoperative AF/AFL after coronary bypass surgery.