Downstaging and Survival Associated with Neoadjuvant Immunotherapy Before Radical Cystectomy for Muscle-invasive Bladder Cancer

BACKGROUND

Neoadjuvant cisplatin-containing chemotherapy before radical cystectomy is the standard of care for patients with localized muscle-invasive bladder cancer (MIBC). However, a large proportion of patients are ineligible for cisplatin. Single-arm phase 2 neoadjuvant immunotherapy trials have reported promising tumor response rates, but interpretation is limited owing to lack of a comparator arm.

OBJECTIVE

To compare rates of pathologic downstaging and overall survival between patients receiving neoadjuvant immunotherapy (NAI), neoadjuvant chemotherapy (NAC), or no neoadjuvant therapy (NNAT).

DESIGN, SETTING, AND PARTICIPANTS

We identified 18 483 patients in the National Cancer Data Base who were diagnosed with clinically localized MIBC and underwent radical cystectomy from 2014 to 2019.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Nearest-neighbor propensity-score caliper matching was used to create three demographically similar and equally sized cohorts stratified by NAT receipt. Logistic regression was used to examine the association of treatment received with pathologic downstaging to pT0N0 and pT < 2N0. Cox proportional-hazards regression was used to assess the association of treatment received with overall survival (OS).

RESULTS AND LIMITATIONS

Propensity score matching yielded three equally sized cohorts without significant differences in baseline characteristics (n = 840). The NAI group had a higher rate of pathologic downstaging to pT0N0 than the NNAT group and a similar rate to the NAC group (NNAT 6.7% vs NAC 26.4%, odds ratio 5.0, 95% confidence interval [CI] 2.9-8.3; NAI 22.5%, odds ratio 4.0, 95% CI 2.4-7.1). The NAI group had better OS than the NNAT group and similar OS to the NAC group (NAC: hazard ratio 0.62, 95% CI 0.42-0.92; NAI: hazard ratio 0.68, 95% CI 0.46-0.97, with NNAT as the reference). The primary limitation is selection bias from confounding by clinical indication.

CONCLUSIONS

NAI is a promising alternative to NAC for patients with clinically localized MIBC, as evidenced by similar pathologic downstaging rates and OS benefits in comparison to no NAT. Phase 3 trials should be conducted to test the noninferiority of NAI to NAC.

PATIENT SUMMARY

We compared outcomes for patients with muscle-invasive bladder cancer according to whether they received chemotherapy, immunotherapy, or no medical therapy before surgical removal of their bladder. We found that preoperative immunotherapy improved patient survival and regression of the cancer stage in comparison to no medical therapy, similar to the outcomes seen with preoperative chemotherapy. Randomized clinical trials are needed to confirm these findings.

"Notice of major cleaning": A qualitative study of the negative impact of encampment sweeps on the ontological security of unhoused people who use drugs

BACKGROUND

Unhoused people who use drugs in the United States are at risk for a variety of negative health outcomes. As the crisis of houselessness continues to impact major urban areas, a wave of punitive policies has been enacted to remove visible unhoused people from public spaces. There is reason to believe that harsh policies of encampment displacement will have negative immediate and downstream impacts on this community.

METHODS

Participant observation was conducted weekly or bi-weekly at unhoused encampments in Los Angeles County, USA over the course of two years (2021, 2022). Data were generated through the lens of ontological security theory via in-field jottings and comprehensive field notes. Formal, semi-structured qualitative interviews were conducted with 30 unhoused people who use drugs recruited primarily through peer-referral sampling at these same venues. Data were coded and analyzed thematically using the Template Analysis approach. Field notes were used to triangulate and further contextualize thematic analysis of interview data.

RESULTS

Encampment sweeps impacted nearly all participants and occurred multiple times at every visited field site. They were observed to occur both with and without the presence of police, but always resulted in the loss of the personal property of encampment residents. Sweeps occurred across seasons, hazardous weather, and without offers of alternative shelter. Participants described sweeps as impacting all aspects of their ontological security, including dismantling material and social constancy, disrupting routines of daily life and resource management, increasing feelings of surveillance, and potentially creating negative identity formation.

CONCLUSIONS

In both ethnographic observation and participant interviews, encampment sweeps were noted to be physically, psychologically, and socially destructive. Sweeps left participants feeling anger, loss, and hopelessness while further driving the societal marginalization of unhoused people who use drugs. Sweeps should be discontinued as they harm the capacity of unhoused people to improve their well-being.

Mirror Therapy for the Management of Phantom Limb Pain: A Single- Center Experience

BACKGROUND

Phantom limb pain (PLP) can have devastating consequences, affecting up to 90% of amputees. PLP is associated with analgesia dependence and impaired quality of life. Mirror therapy (MT) is a novel treatment that has been applied in other pain syndromes. We prospectively evaluated MT in the management of PLP.

METHODS

A prospective study of patients recruited between 2008 and 2020 who underwent unilateral major limb amputation, with a healthy contralateral limb. Participants were invited to attend weekly MT sessions. Pain in the 7 days prior to each MT session was scored on a Visual Analog Scale (VAS: 0-10 mm) and the short form McGill pain questionnaire.

RESULTS

Ninety eight patients (68 males and 30 females) aged 17-89 years were recruited over 12 years. Forty four percent of patients had amputations due to peripheral vascular disease. Over an average of 2.5 sessions, the final treatment score on the VAS scale was 2.6 (standard deviation ± 3.0) with a reduction of 4.5 points on VAS score. As a comparison using the short form McGill pain questionnaire scoring system, the average final treatment score was 3.2 (± 5.0) with 91% overall improvement.

CONCLUSIONS

MT is a very powerful and effective intervention for PLP. It is an exciting addition to the armory of vascular surgeons in the management of this condition.

Imaging characteristics predicting elevated detrusor pressures in patients with spina bifida

PURPOSE

Patients with spina bifida require urologic follow up with assessments of bladder and renal function. The ideal screening protocol for bladder compliance remains controversial. This study assessed associations between bladder end filling pressure (EFP) and detrusor leak point pressure (DLPP) on urodynamic studies (UDS) and findings from renal bladder ultrasounds (RBUS) and voiding cystourethrograms (VCUG).

METHODS

Pediatric spina bifida patients who underwent RBUS and/or VCUG within six months of UDS at a single institution from 2015 to 2021 were retrospectively reviewed. Demographics, VCUG and RBUS results, and UDS EFP and DLPP were recorded. Multiple linear regression analyses and Pearson chi-square tests were conducted to correlate RBUS and VCUG findings with DLPP/EFP.

RESULTS

129 patients were included. In adjusted analyses, moderate to severe hydronephrosis on RBUS was significantly associated with elevations in mean DLPP/EFP (p = 0.006). Patients with round bladders had significantly lower mean DLPP/EFP than patients with elongated or conical bladders (p < 0.0001). The presence of trabeculations was associated with increased mean DLPP/EFP (p < 0.0001) and increases in severity of trabeculations were associated with higher DLPP/EFP (p < 0.0001). The presence of vesicoureteral reflux (VUR) on VCUG was not associated with significant differences in mean DLPP/EFP (p = 0.20).

CONCLUSIONS

Abnormal bladder shape and trabeculations on VCUGs in spina bifida patients had significant associations with increased mean bladder pressures on UDS. Assessment of bladder shape and contour by VCUG may be a valuable screening tool in conjunction with routine RBUS in determining the need for further assessment of bladder pressures in patients with spina bifida.

Bilateral Wilms’ Tumor in a Female with Simpson-Golabi-Behmel Syndrome

A 20-month-old female presented with a palpable abdominal mass. Imaging revealed bilateral renal masses and pulmonary nodules. The genetic evaluation identified a de novo 540kb X-chromosome deletion involving GPC3, PHF6, and HPRT1, and highly skewed X-inactivation (100:0). This clinical picture was suggestive of Wilms’ tumor in the setting of Simpson-Golabi-Behmel Syndrome.

Ethical challenges with CAR T slot allocation with idecabtagene vicleucel manufacturing access

e20021

Background: CAR T cell therapies are FDA approved for patients with triple refractory multiple myeloma (MM) and >4 lines of therapy. The median survival of this is group is less than 12 months so salvage therapies need to be implemented quickly. Real-world access to CAR T remains challenging due to supply chain limitations impacting manufacturing. The goal of this study was to evaluate how centers are handling the challenges of CAR T slot allocation. Methods: MM CAR T physician leaders at each CAR T treatment center certified for idecabtagene vicleucel across the US were surveyed. Results: We received responses from 15/20 centers. Summary of CAR T volumes and outcomes of patient on waitlists are shown in the table. The median time on the waiting list was 6 months with only 25% of patients receiving CAR T eventually. For patient selection, all centers reported using a committee of experienced CART physicians to ensure consistency. Selection committee included: primary MD (n=9), CAR T MD (n=12), social workers (n=3), CAR T RN (n=10), APP (n=2), pharmacists (n=2) and ethicists (n=1). To ensure transparency, centers have clear selection criteria (n=10), priority score (n=8) and selection timeline (n=11) . To ensure accountability, centers document priority scores (n=5) and have pre-specified criteria (n=9) for selection. Centers also reported using ethical principles for selection: a) equal treatment: time spent on waiting list (n=8); b) priority to the worst-off: limited therapeutic options (n=10), MM burden (n=7), ineligible for trials (n=2); c) maximize benefit: most likely to complete apheresis (n=8) or infusion (n=8) or achieve response (n=6) and d) social value: younger pts (n=2). Maximizing benefit was considered the most important criterion by 7 centers. Conclusions: More stringent GMP manufacturing requirements with FDA approved CAR T and real-world practice with broader patient demographics can present challenges to implementation of CAR T in standard of practice. Our study is the first attempt to evaluate and highlight existing issues with MM CAR T access and the variability and challenges in patient selection. Learning from other models of resource allocation (ex: UNOS) and sharing experience across centers can help providers optimize slot allocation to improve accrual. Increasing supplies of key reagents and novel manufacturing methods(eg: non-viral vectors and allogeneic CAR) could help overcome these limitations. [Table: see text]

ASTCT Clinical Practice Recommendations for Transplantation and Cellular Therapies in Multiple Myeloma

Over the past decade, therapeutic options in multiple myeloma (MM) have changed dramatically. Given the unprecedented efficacy of novel agents, the role of hematopoietic cell transplantation (HCT) in MM remains under scrutiny. Rapid advances in myeloma immunotherapy including the recent approval of chimeric antigen receptor (CAR) T-cell therapy will impact the MM therapeutic landscape. The American Society for Transplantation and Cellular Therapy convened an expert panel to formulate clinical practice recommendations for role, timing, and sequencing of autologous (auto-HCT), allogeneic (allo-HCT) and CAR T-cell therapy for patients with newly diagnosed (NDMM) and relapsed/refractory MM (RRMM). The RAND-modified Delphi method was used to generate consensus statements. Twenty consensus statements were generated. The panel endorsed continued use of auto-HCT consolidation for patients with NDMM as a standard-of-care option, whereas in the front line allo-HCT and CAR-T were not recommended outside the setting of clinical trial. For patients not undergoing auto-HCT upfront, the panel recommended its use in first relapse. Lenalidomide as a single agent was recommended for maintenance especially for standard risk patients. In the RRMM setting, the panel recommended the use of CAR-T in patients with 4 or more prior lines of therapy. The panel encouraged allo-HCT in RRMM setting only in the context of clinical trial. The panel found RAND-modified Delphi methodology effective in providing a formal framework for developing consensus recommendations for the timing and sequence of cellular therapies for MM.

Biotransformation of phthalate plasticisers and bisphenol A by marine and freshwater fungi

Phthalate esters (PEs) are environmentally ubiquitous micropollutants that are used as plasticizers and additives in diverse consumer products. Considerable concern relates to their reported xenoestrogenicity and the microbial-based attenuation of environmental PE concentrations is of interest to combat harmful downstream effects. Fungal PE catabolism has received less attention than that by bacteria, and particularly marine fungal species remain largely overlooked in this respect. We have compared the biocatalytic and biosorptive removal rates of di-n-butyl phthalate (DBP) and diethyl phthalate (DEP), chosen as two environmentally prominent PE representatives (exhibiting differing structures and hydrophobicities), by marine- and freshwater fungal strains. Bisphenol A, both an extensively used plastic additive and prominent environmental xenoestrogen, was included as a reference compound due to its previously well-documented fungal degradation. Partial pathways for DBP metabolization by these ecophysiologically diverse ascomycetes were proposed with the help of UPLC-QTOF-MS analysis. Species-specific biochemical reaction steps contributing to DBP metabolism were also observed. The involved reactions include initial cytochrome P450-dependent monohydroxylations of DBP with subsequent further oxidation of related metabolites, de-esterification via either hydrolytic cleavage or cytochrome P450-dependent oxidative O-dealkylation, transesterification, and demethylation steps - finally yielding phthalic acid as a central intermediate in all pathways. Beyond previous research into fungal PE metabolism which emphasises hydrolytic de-esterification as the primary catabolic step, a prominent role of cytochrome P450 monooxygenase-catalysed reactions is established.

Virtual Reality vs. Dry-Lab Models: Comparing automated performance metrics and cognitive workload during robotic simulation training

Background This study compares surgical performance during analogous vesico-urethral anastomosis (VUA) tasks in two robotic training environments, virtual reality (VR) and dry-lab (DL), in order to investigate transferability of skills assessment across the two platforms. Utilizing computer-generated performance metrics and pupillary data we evaluated the two environments' ability to distinguish surgical expertise and ultimately whether performance in the VR simulation correlates to performance on the live robot in the dry-lab. Materials and Methods Experts (≥ 300 cases) and trainees (<300) performed analogous VUAs during VR and dry-lab sessions on a da Vinci robotic console. 22 metrics were generated in each environment (kinematic metrics, tissue metrics, biometrics). The dry-lab included 18 previously validated automated performance metrics (APMs) (kinematics, events metrics) and were captured by an Intuitive systems data recorder. In both settings, Tobii Pro Glasses 2 recorded task-evoked pupillary response (reported as Index of Cognitive Activity [ICA]) to indicate cognitive workload, analyzed by EyeTracking Cognitive Workload Software. Pearson Correlation, Mann-Whitney and Independent t-tests were used for the comparative analyses. Results Our study included 6 experts (median caseload 1300 [interquartile range 400-3000]) and 11 trainees (25 [0-250]). 8/9 metrics directly comparable between VR and DL showed significant positive correlation (r≥0.554, p≤0.032). 5/22 VR metrics distinguished expertise including: task time (p=0.031), clutch usage (p=0.040), unnecessary needle piercings (p=0.026) and suspected injury to endopelvic fascia (p=0.040). This contrasts with 14/22 APMs in dry-lab (p≤0.038) including: linear velocities of all three instruments (p≤0.038) and dominant-hand instrument wrist articulation (p=0.013). Trainees experienced higher cognitive workload (ICA) in both environments when compared to experts (p<0.036). Conclusions A majority of performance metrics between VR and dry-lab exhibited moderate to strong correlations, showing transferability of skills across the platforms. Comparing training environments, APMs during dry-lab tasks are better able to distinguish expertise than VR-generated metrics.

Role of molecular signature to differentiate second primary lung cancer from metastasis in a patient with squamous cell carcinoma of oral cavity

Background

Lung is the most common site of distant metastasis for patients with head and neck squamous cell carcinoma (HNSCC). However, differentiating second primary lung cancers from metastasis may be difficult for p16 negative HNSCC.

Case

We describe a case of oral cavity squamous cell carcinoma (SCC) who was found to have lung nodule and hilar lymphadenopathy (LAD) after surgery and radiation therapy. Hilar node was consistent with SCC however, it was difficult to differentiate second primary lung cancer and metastasis from oral cavity SCC.

Next‐generation sequencing was done for the primary oral cavity and the hilar node. Both samples had the same type of TP53 mutation and variants of unknown significance suggesting metastatic HNSCC. He was treated with a chemotherapy regimen for metastatic HNSCC.

Conclusion

Molecular studies can help to differentiate metastasis from second primary lung cancers for p16 negative HNSCC.

Abstract 6474: FAT1 and CASP8 co-mutations are associated with poor prognosis in HPV negative head and neck squamous cell carcinoma

INTRODUCTION: FAT1 alterations with somatic mutations or deletions are observed in head and neck squamous cell carcinomas (HNSCC). These alterations lead to loss of function of FAT1. FAT1 loss of function was known to be associated with aberrant Wnt activation, cell migration and invasion. In this study, we present analysis and outcomes of co-mutations seen in FAT1-mutation positive HNSCC.

METHODS: TCGA data were analyzed for mutation, gene expression data and overall survival. We examined mutation data in 415 HPV negative samples and 72 HPV positive samples. The Fisher's Exact test was used to determine if differences in mutation frequency existed between the different cohorts. Mantel-Cox method was used for overall survival (OS) comparison between the cohorts.

RESULTS: FAT1 somatic mutation was the third most commonly mutated gene in HPV-negative HNSCC while it was not common in HPV-positive HNSCC. FAT1 mutation was seen in 25.8% of HPV negative HNSCC (107/415), while 4.2% (3/72) HPV positive HNSCC had FAT1 mutation. We then analyzed the frequency of co-mutations in FAT1-mutated HPV-negative HNSCC. CDKN2A, NOTCH1, CASP8, FBXW7, ZFHX4, HRAS, DCC, ATR mutations were more common in FAT1-mutated cancers. CASP8 mutation was seen in 24.30% (26 out of 107 samples) of FAT1-mutations positive HPV negative HNSCC, while it was less common in FAT1-mutation negative HNSCC (9.08% 28/308) (P=0.002). The patients with FAT1 and CASP8 co-mutation were associated with shorter overall survival when compared with patients with FAT1-mutation (19.8 months vs 52.3 months P=0.02). FAT1 only or CASP8 only mutation without co-mutation did not affect survival. To determine the mutation impact of the FAT1 and CASP8 mutations in HNSCC, differentially expressed genes between mutated and non-mutated genes were analyzed in HNSCC. CASP8 mutation was the top gene among the genes with somatic mutation in HNSCC and associated with gene expression changes in more than 6000 genes. FAT1 was ranked 11th resulting in differential gene expression in more than 1000 genes.

DISCUSSION: FAT1 somatic mutations are commonly seen in HPV negative HNSCC. We have demonstrated for the first time that CASP8 and FAT1 co-mutations are associated with poor prognosis with decreased overall survival in HPV negative HNSCC. Both CASP8 and FAT1 mutations are among the top genes with mutation impact on differential gene expression in HNSCC suggesting significance of these mutations in HNSCC.

Citation Format: Emrullah Yilmaz, David Lee, Andrew Cowan, Gregory Gan, Michelle Ozbun, Yan Guo. FAT1 and CASP8 co-mutations are associated with poor prognosis in HPV negative head and neck squamous cell carcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6474.

Community exchange and time currencies: a systematic and in-depth thematic review of impact on public health outcomes

OBJECTIVES

Austerity in government funding, and public service reform, has heightened expectations on UK communities to develop activities and resources supportive of population health and become part of a transformed place-based system of community health and social care. As non-monetary place-based approaches, Community Exchange/Time Currencies could improve social contact and cohesion, and help mobilise families, neighbourhoods, communities and their assets in beneficial ways for health. Despite this interest, the evidence base for health outcomes resulting from such initiatives is underdeveloped.

STUDY DESIGN

A systematic review.

METHODS

A literature review was conducted to identify evidence gaps and advance understanding of the potential of Community Exchange System. Studies were quality assessed, and evidence was synthesised on 'typology', population targeted and health-related and wider community outcomes.

RESULTS

The overall study quality was low, with few using objective measures of impact on health or well-being, and none reporting costs. Many drew on qualitative accounts of impact on health, well-being and broader community outcomes. Although many studies lacked methodological rigour, there was consistent evidence of positive impacts on key indicators of health and social capital, and the data have potential to inform theory.

CONCLUSIONS

Methodologies for capturing impacts are often insufficiently robust to inform policy requirements and economic assessment, and there remains a need for objective, systematic evaluation of Community Exchange and Time Currency systems. There is also a strong argument for deeper investigation of 'programme theories' underpinning these activities, to better understand what needs to be in place to trigger their potential for generating positive health and well-being outcomes.

Modified VR-CAP, Alternating With Rituximab and High-dose Cytarabine: An Effective Pre-transplant Induction Regimen for Mantle Cell Lymphoma

BACKGROUND

Initial treatment of mantle cell lymphoma (MCL) incorporating autologous stem cell transplantation affords long-term remissions, but relapses still occur. Optimal pretransplant therapy will afford high complete response rates and not impair stem cell collection. Incorporation of bortezomib represents a natural evolution of pretransplant therapy, given its proven first-line efficacy and minimal impact on stem cell collection.

PATIENTS AND METHODS

At the University of Washington/Seattle Cancer Care Alliance and the Cleveland Clinic Foundation, we developed modified VR-CAP/R+ara-C (bortezomib, rituximab, cyclophosphamide, doxorubicin, and prednisone, alternating with rituximab and high-dose cytarabine), for transplant-eligible patients with MCL. This regimen was administered as standard-of-care, pretransplant therapy to consecutive patients with MCL from April 2015 to the present.

RESULTS

A total of 37 patients were treated with this regimen, including 18 at the University of Washington/Seattle Cancer Care Alliance and 19 at the Cleveland Clinic Foundation. Most patients had intermediate- or high-risk disease by both (mantle-cell lymphoma international prognostic index (MIPI)-B and MIPI-C category. Complete response to induction was achieved in 32 (86%) of 37 evaluable patients; 2 achieved partial response, and 3 had primary refractory disease. Stem cell collection was successful in 1 attempt in 30 of 32 patients. The median follow-up of survivors measured from start of treatment is 17.4 months. Five patients have progressed, and 4 have died (2 owing to lymphoma, 2 from toxicity).

CONCLUSION

Modified VR-CAP/R+ara-C is feasible pretransplant therapy for patients with MCL and is associated with a high rate of complete response and eligibility for autologous stem cell transplantation.

Total Body Irradiation Is Safe and Similarly Effective as Chemotherapy-Only Conditioning in Autologous Stem Cell Transplantation for Mantle Cell Lymphoma

Autologous stem cell transplant (ASCT) consolidation has become a standard approach for patients with mantle cell lymphoma (MCL), yet there is little consensus on the role of total body irradiation (TBI) as part of high-dose transplantation conditioning. We analyzed 75 consecutive patients with MCL who underwent ASCT at our institution between 2001 and 2011 with either TBI-based (n = 43) or carmustine, etoposide, cytarabine, melphalan (BEAM; n = 32) high-dose conditioning. Most patients (97%) had chemosensitive disease and underwent transplantation in first remission (89%). On univariate analysis, TBI conditioning was associated with a trend toward improved PFS (hazard ratio [HR], .53; 95% confidence interval [CI], .28-1.00; P = .052) and similar OS (HR, .59; 95% CI, .26-1.35; P = .21), with a median follow-up of 6.3 years in the TBI group and 6.6 years in the BEAM group. The 5-year PFS was 66% in the TBI group versus 52% in the BEAM group; OS was 82% versus 68%, respectively. However, on multivariate analysis, TBI-based conditioning was not significantly associated with PFS (HR, .57; 95% CI .24-1.34; P = .20), after controlling for age, disease status at ASCT, and receipt of post-transplantation rituximab maintenance. Likewise, early toxicity, nonrelapse mortality, and secondary malignancies were similar in the 2 groups. Our data suggest that both TBI and BEAM-based conditioning regimens remain viable conditioning options for patients with MCL undergoing ASCT.

Atypical IgG4+ Plasmacytic Proliferations and Lymphomas: Characterization of 11 Cases

OBJECTIVES

To report the clinicopathologic features of monotypic immunoglobulin G4+ (IgG4+) lymphoid and plasmacytic proliferations.

METHODS

Cases were identified from the pathology files. Pathology and clinical materials were reviewed.

RESULTS

Eleven cases of monotypic IgG4+ proliferations were identified at nodal, orbital, or salivary sites. Six cases (three men, three women; age, 57-94 years) met criteria for lymphoma or plasma cell neoplasia. Most contained frequent Mott cells. Five cases (three men, two women; age, 40-80 years) had restricted proliferations of atypical/monotypic IgG4+ plasma cells in a background of reactive lymphoid hyperplasia or inflammation.

CONCLUSIONS

Monotypic IgG4+ proliferations include lymphomas, plasmacytic neoplasms, and a previously uncharacterized group of proliferations not meeting criteria for conventional hematolymphoid neoplasia. Distinct features included prominent Mott cells and/or monotypic plasma cells within follicles. The proliferations were infrequently associated with IgG4-related disease (IgG4-RD). Our findings raise questions regarding the relationship between clonal IgG4+ proliferations, reactive/inflammatory processes, and IgG4-RD.

Pegylated GCSF Can Be Used With First-Line da-EPOCH-R Without Compromising Dose Intensity, Safety, or Efficacy

INTRODUCTION

Infusional da-EPOCH-R (dose-adjusted etoposide, doxorubicin, and cyclophosphamide with vincristine, prednisone, and rituximab) is a dose-intensified regimen with a potential role in treating high-risk subtypes of aggressive B-cell non-Hodgkin lymphoma (B-NHL). Studies of da-EPOCH-R use daily injections of granulocyte colony-stimulating factor (GCSF) to tailor chemotherapy dosing, and whether 1-time administration of pegylated GCSF (peg-GCSF) is as efficacious has not been addressed.

PATIENTS AND METHODS

We reviewed aggressive B-NHL patients treated at our center with first-line da-EPOCH-R for clinician choice of growth factor, and analyzed dose level achieved, rate of unplanned hospitalizations, and patient outcomes.

RESULTS

Among 73 patients, 44 received peg-GCSF. Overall, 11 patients (15%) patients achieved dose level 4. Baseline characteristics between peg-GCSF and GCSF groups were similar. The proportion of patients who achieved dose level 4 was comparable in the peg-GCSF group (5 of 44 [11%]) and daily GCSF (6 of 29 [21%]; P = .24). The rate of unplanned hospitalizations, and event-free and overall survival, were also similar between groups.

CONCLUSION

We suggest routine use of peg-GCSF is an acceptable alternative to daily GCSF, for patients in whom da-EPOCH-R is selected as first-line treatment for aggressive B-NHL.

Phoenixin: A candidate pruritogen in the mouse

Phoenixin (PNX) is a 14-amino acid amidated peptide (PNX-14) or an N-terminal extended 20-residue amidated peptide (PNX-20) recently identified in neural and non-neural tissue. Mass spectrometry analysis identified a major peak corresponding to PNX-14, with negligible PNX-20, in mouse spinal cord extracts. Using a previously characterized antiserum that recognized both PNX-14 and PNX-20, PNX-immunoreactivity (irPNX) was detected in a population of dorsal root ganglion (DRG) cells and in cell processes densely distributed to the superficial layers of the dorsal horn; irPNX cell processes were also detected in the skin. The retrograde tracer, Fluorogold, injected subcutaneously (s.c.) to the back of the cervical and thoracic spinal cord of mice, labeled a population of DRG, some of which were also irPNX. PNX-14 (2, 4 and 8 mg/kg) injected s.c.to the nape of the neck provoked dose-dependent repetitive scratching bouts directed to the back of the neck with the hindpaws. The number of scratching bouts varied from 16 to 95 in 30 min, commencing within 5 min post-injection and lasted 10-15 min. Pretreatment of mice at -20 min with nalfurafine (20 μg/kg, s.c.), the kappa opioid receptor agonist, significantly reduced the number of bouts induced by PNX-14 (4 mg/kg) compared with that of saline-pretreated mice. Our results suggest that the peptide, PNX-14, serves as one of the endogenous signal molecules transducing itch sensation in the mouse.

Zyklophin, a short-acting kappa opioid antagonist, induces scratching in mice

It has been shown previously that norbinaltorphimine (norBNI) and 5'-guanidinonaltrindole (5'-GNTI), long-acting kappa opioid receptor (KOPR) antagonists, cause frenzied scratching in mice [1,2]. In the current study, we examined if zyklophin, a short-acting cyclic peptide KOPR antagonist, also elicited scratching behavior. When injected s.c. in the nape of the neck of male Swiss-Webster mice, zyklophin at doses of 0.1, 0.3 and 1mg/kg induced dose-related hindleg scratching of the neck between 3 and 15 min after injection. Pretreating mice with norBNI (20mg/kg, i.p.) at 18-20 h before challenge with zyklophin (0.3mg/kg) did not markedly affect scratching. Additionally, KOPR-/- mice given 0.3mg/kg of zyklophin displayed similar levels of scratching as wild-type animals. The absence of KOPR in KOPR-/- mice was confirmed with ex vivo radioligand binding using [(3)H]U69,593. Taken together, our data suggest that the presence of kappa receptors is not required for the excessive scratching caused by zyklophin. Thus, zyklophin, similar to the structurally different KOPR antagonist 5'-GNTI, appears to act at other targets to elicit scratching and potentially the sensation of itch.

Usability evaluation of HemOnc.org, a collaborative online hematology/oncology reference

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Background: With an ever-growing body of medical knowledge, open access to accurate information is critical to quality care. HemOnc.org is a free online collaborative wiki created by health care professionals to record, access, and share information about chemotherapy treatment regimens and drugs. As of June 2013, the site contains referenced information for 931 regimens and 316 drugs. The site receives >7,000 visits/mo and has had >425,000 total page views from around the world (29% from outside the United States). We conducted a survey to evaluate the usability of the site. Methods: The survey was open May 1 to May 31, 2013. Participants were invited by site announcements, social media, and emails to hematology/oncology fellowship programs. Usability was assessed by 100-point scales (higher = better). Other data were collected via multiple choice questions with optional free text entry. Results: There were 139 respondents; demographics are shown in the Table. They felt that the site was useful (median 90, interquartile range (IQR) 76-99.5), usable (median 85, IQR 69-98), and recommendable to colleagues (median 87, IQR 72-99). Although 100% of users reported using other references (e.g. textbooks), 70.5% reported accuracy issues with these references (Table). Conclusions: HemOnc.org provides a new way to access and share curated knowledge. No resource is 100% accurate, but the open and transparent nature of the site allows users to actively correct errors and inconsistencies. Feedback has been positive, suggesting that an unmet need for information is being satisfied. Our goal is to improve collaboration, foster greater knowledge sharing among the oncology community, and improve quality of care through open dissemination of accurate information to a widespread audience. [Table: see text]

Nalfurafine prevents 5'-guanidinonaltrindole- and compound 48/80-induced spinal c-fos expression and attenuates 5'-guanidinonaltrindole-elicited scratching behavior in mice

The aims of the present study were to establish if nalfurafine, a kappa opioid agonist, inhibits compulsive scratching in mice elicited by the s.c. administration (behind the neck) of 5'-guanidinonaltrindole (GNTI), a kappa opioid antagonist; to assess if nalfurafine prevents c-fos expression provoked by GNTI or compound 48/80, two chemically diverse pruritogens; and to distinguish on the basis of neuroanatomy, those neurons in the brainstem activated by either GNTI-induced itch or formalin-induced pain (both compounds given s.c. to the right cheek). Pretreatment of mice with nalfurafine (0.001-0.03 mg/kg s.c.) attenuated GNTI (0.3 mg/kg)-evoked scratching dose-dependently. A standard antiscratch dose of nalfurafine (0.02 mg/kg) had no marked effect on the spontaneous locomotion of mice. Tolerance did not develop to the antiscratch activity of nalfurafine. Both GNTI and compound 48/80 provoked c-fos expression on the lateral side of the superficial layer of the dorsal horn of the cervical spinal cord and pretreating mice with nalfurafine inhibited c-fos expression induced by both pruritogens. In contrast to formalin, GNTI did not induce c-fos expression in the trigeminal nucleus suggesting that pain and itch sensations are projected differently along the sensory trigeminal pathway. Our data indicate that the kappa opioid system is involved, at least in part, in the pathogenesis of itch; and that nalfurafine attenuates excessive scratching and prevents scratch-induced neuronal activity at the spinal level. On the basis of our results, nalfurafine holds promise as a potentially useful antipruritic in human conditions involving itch.

Lack of interaction between metoclopramide and morphine in vitro and in mice

1. This study examined interactions via common metabolism or via common pharmacodynamic pathways between frequently co-prescribed metoclopramide (a prokinetic) and morphine (an opioid analgesic). 2. In human liver microsomes, morphine 3-glucuronide and morphine 6-glucuronide formation had V(max) estimates of 6.2 +/- 0.07 and 0.75 +/- 0.01 (nmole min(-1) mg(-1) protein) and K(m) estimates of 1080 +/- 37 and 665 +/- 55 (microM), respectively. The in vitro K(i) for morphine 3-glucuronide formation in the presence of metoclopramide in human liver microsomes or recombinant uridine diphosphoglucuronosyltransferase 2B7 predicted a lack of in vivo interaction. 3. Morphine (2 mg kg(-1) subcutaneously) delayed gastrointestinal meal transit in mice, metoclopramide (10 mg kg(-1) subcutaneously) had no effect on meal transit, and metoclopramide did not alter this effect of morphine. 4. Morphine (2 or 5 mg kg(-1) subcutaneously) was antinociceptive in mice (hot plate test) and metoclopramide (10 mg kg(-1) subcutaneously) did not alter the antinociceptive effects of morphine. 5. Together, the data suggest a lack of interaction between morphine and metoclopramide.

Electromagnetic millimeter wave induced hypoalgesia: frequency dependence and involvement of endogenous opioids

Millimeter wave treatment (MMWT) is based on the systemic biological effects that develop following local skin exposure to low power electromagnetic waves in the millimeter range. In the present set of experiments, the hypoalgesic effect of this treatment was analyzed in mice. The murine nose area was exposed to MMW of "therapeutic" frequencies: 42.25, 53.57, and 61.22 GHz. MMWT-induced hypoalgesia was shown to be frequency dependent in two experimental models: (1) the cold water tail-flick test (chronic non-neuropathic pain), and (2) the wire surface test (chronic neuropathic pain following unilateral constriction injury to the sciatic nerve). Maximum hypoalgesic effect was obtained when the frequency was 61.22 GHz. Other exposure parameters were: incident power density = 13.3 mW/cm(2), duration of each exposure = 15 min. Involvement of delta and kappa endogenous opioids in the MMWT-induced hypoalgesia was demonstrated using selective blockers of delta- and kappa-opioid receptors and the direct ELISA measurement of endogenous opioids in CNS tissue. Possible mechanisms of the effect and the perspectives of the clinical application of MMWT are discussed.

Transcatheter Embolization of a Renal Arteriovenous Fistula Complicated by an Aneurysm of the Feeding Renal Artery

Renal arteriovenous fistula (AVF) is rare. Renal AVF complicated by aneurysm of the feeding artery presents a technical challenge for endovascular treatment. We report a case managed by covered stenting of the renal artery aneurysm, coil embolization of the fistula, and bare stenting of the aorta.

An antisense oligodeoxynucleotide to the mu opioid receptor attenuates cocaine-induced behavioral sensitization and reward in mice

Numerous studies support a role for the endogenous opioid system in cocaine-influenced behavior. Few of these studies, however, selectively delineate a role for the mu opioid receptor (MOR) in this regard. This investigation examined if the MOR modulates cocaine-induced behavior in mice using a 17-base antisense oligodeoxynucleotide (AS ODN) directed against the MOR coding sequence 16-32. Specifically, cocaine-induced behavioral sensitization and conditioned reward were investigated. For the sensitization study, C57BL/6J mice received eight intermittent i.c.v. infusions of saline, mismatch oligodeoxynucleotide (ODN) (20 microg/4 microl) or AS ODN (20 microg/4 microl) over 20 days. Mice also received concomitant once daily i.p. injections of saline (4 ml/kg) or cocaine (15 mg/kg) for 10 days. There was a 7-day withdrawal period, after which all mice were challenged with cocaine (15 mg/kg) to test for behavioral sensitization. For the conditioned place preference (CPP) study, mice received five i.c.v. infusions of mismatch ODN or MOR AS ODN (days 1-5). An unbiased counterbalanced conditioning procedure was used where mice were conditioned with saline (4 ml/kg, i.p.) and cocaine (15 mg/kg, i.p.) on alternate days for four sessions (days 3-6). Mice were tested on day 7 for CPP. Immediately following testing, [3H]DAMGO (D-Ala2, N-Me-Phe4, Gly-ol5-enkephalin) receptor binding to brain homogenates was conducted. MOR AS attenuated cocaine-induced behavioral sensitization and conditioned reward. MOR AS ODN also reduced [3H]DAMGO binding. Collectively, these findings implicate the MOR as playing an important neuromodulatory role in the behavioral effects of cocaine in mice.

Icilin evokes a dose- and time-dependent increase in glutamate within the dorsal striatum of rats

Icilin, the peripheral cold channel agonist, activates TRPM8 and TRPA1, localized on dorsal root ganglia and trigeminal neurons in rats. Icilin precipitates immediate wet-dog shakes in this species, which are antagonized by centrally acting mu and kappa opioid agonists, implicating the central nervous system in the behavioral response. We studied the effect icilin has on glutamate levels in the dorsal striatum, a brain region involved in movement. Icilin (0.25, 0.5 and 0.75 mg/kg, i.p.) elicited a dose- and time-dependent increase in glutamate within the striatum, indicative of icilin's neurochemical effect in rats.

N-methyl-D-aspartate antagonists and WIN 55212-2 [4,5-dihydro-2-methyl-4(4-morpholinylmethyl)-1-(1-naphthalenyl-carbonyl)-6H-pyrrolo[3,2,1-i,j]quinolin-6-one], a cannabinoid agonist, interact to produce synergistic hypothermia

CB(1) cannabinoid receptors mediate profound hypothermia when cannabinoid agonists are administered to rats. Glutamate, the principal excitatory neurotransmitter in the central nervous system (CNS), is thought to tonically increase body temperature by activating N-methyl-D-aspartate (NMDA) receptors. Because NMDA antagonists block cannabinoid-induced antinociception and catalepsy, intimate glutamatergic-cannabinoid interactions may exist in the CNS. The present study investigated the effect of two NMDA antagonists on the hypothermic response to WIN 55212-2 [4,5-dihydro-2-methyl-4(4-morpholinylmethyl)-1-(1-naphthalenyl-carbonyl)-6H-pyrrolo[3,2,1-i,j]quinolin-6-one], a selective cannabinoid agonist, in rats. WIN 55212-2 (1-10 mg/kg i.m.) produced dose-dependent hypothermia that peaked 60 to 180 min postinjection. Dextromethorphan (5-75 mg/kg i.m.), a noncompetitive NMDA antagonist, or LY 235959 [(-)-6-[phosphonomethyl-1,2,3,4,4a,5,6,7,8,8a-decahydro-isoquinoline-2-carboxylate]](1-4 mg/kg i.m.), a competitive and highly selective NMDA antagonist, evoked hypothermia in a dose-sensitive manner, suggesting that endogenous glutamate exerts a hyperthermic tone on body temperature. A dose of dextromethorphan (10 mg/kg) that did not affect body temperature by itself potentiated the hypothermic response to WIN 55212-2 (1, 2.5, or 5 mg/kg). The enhancement was strongly synergistic, indicated by a 2.7-fold increase in the relative potency of WIN 55212-2. Similarly, a dose of LY 235959 (1 mg/kg) that did not affect body temperature augmented the hypothermia associated with a single dose of WIN 55212-2 (2.5 mg/kg), thus confirming that NMDA receptors mediated the synergy. We have demonstrated previously that CB(1) receptors mediate WIN 55212-2-evoked hypothermia in rats. The present data are the first evidence that NMDA antagonists exert a potentiating effect on cannabinoid-induced hypothermia. Taken together, these data suggest that interactions between NMDA and CB(1) receptors produce synergistic hypothermia.

Analgesic and toxic effects of neonicotinoid insecticides in mice

Several nicotinic agonists with the 6-chloro-3-pyridinyl moiety are potent insecticides (e.g., the neonicotinoids imidacloprid and thiacloprid) while others are candidate nonopioid and nonantiinflammatory analgesics (i.e., epibatidine and several heterocyclic analogs). This study examines the hypothesis for the first time that the neonicotinoid insecticides and their imine metabolites and analogs display analgesic (antinociceptive) activity or adverse toxic effects associated with their action on binding to the alpha 4 beta 2 nicotinic acetylcholine receptor (AChR) subtype. Seven 6-chloro-3-pyridinyl compounds were studied, i.e., imidacloprid and thiacloprid, the corresponding imines and an olefin derivative, a nitromethylene analog, and (+/-)-epibatidine. Like (-)-nicotine and carbachol, they all act as full agonists in the (86)rubidium ion efflux experiment with intact mouse fibroblast M10 cells stably expressing the alpha 4 beta 2 nicotinic AChR. Their agonist action is correlated with binding affinity to the alpha 4 beta 2 receptor from M10 cells. Imidacloprid, thiacloprid, and their imine analogs are not antinociceptive agents in mice by abdominal constriction and hot plate analgesic tests. Their agonist actions at the alpha 4 beta 2 receptor correlate instead with their toxicity. Surprisingly, the nitromethylene analog, a weak agonist, is as potent as (-)-nicotine in inducing antinociception, and the effect persists longer than that caused by (-)-nicotine. However, mecamylamine (1 mg/kg) prevents antinociception induced by (-)-nicotine but not by the nitromethylene analog. Interestingly, this nitromethylene neonicotinoid insecticide gives 80-100% mortality within 15 min at 3 mg/kg with mecamylamine pretreatment at 2 mg/kg, doses at which each agent alone gives no lethality. Therefore, analgesic and toxic effects of the nitromethylene analog differ in their mechanism of action from (-)-nicotine and (+/-)-epibatidine.

Morphine inhibits mucosal antibody responses and TGF-beta mRNA in gut-associated lymphoid tissue following oral cholera toxin in mice

In this study, we investigated the effect of morphine on the mucosal immune system using fragment cultures of ileal segments, Peyer's patches (PPs), and mesenteric lymph nodes. Mice were implanted s.c. with a morphine slow release pellet. Control groups received a naltrexone slow release pellet, a placebo pellet, or both a morphine and a naltrexone pellet. After 48 h, mice were orally immunized with cholera toxin (CT) and were boosted orally 1 wk later. Animals were sacrificed 1 wk after the booster immunization, and PPs, mesenteric lymph nodes, and ileal segments were cultured in 24-well plates for 12 days. Morphine resulted in a highly significant inhibition of CT-specific IgA and IgG production in fragment culture supernatants of all three tissues compared with placebo. Naltrexone blocked the reduction in Ab levels induced by morphine, indicating that the effect is opioid receptor mediated. Morphine did not significantly alter total IgA levels in any of the tissue culture supernatants. Morphine also inhibited CT-specific IgA and IgG levels in serum. By flow cytometry, morphine did not alter the lymphoid cell composition in PPs compared with placebo. The effect of morphine on TGF-beta, IL-5, and IL-6 mRNA expression in PPs and ileal segments was determined following oral immunization with CT. Morphine significantly decreased TGF-beta mRNA compared with that in the placebo group, and naltrexone blocked this effect. These results indicate that morphine inhibits Ag-specific IgA responses in gut-associated lymphoid tissue at least partially through the inhibition of TGF-beta, a putative IgA switch factor, in the gastrointestinal tract.

Administration of mu-, kappa- or delta2-receptor agonists via osmotic minipumps suppresses murine splenic antibody responses

Previously, our laboratory has shown that morphine given by implantation of a 75-mg slow-release pellet for 48 h suppresses murine splenic antibody responses to sheep red blood cells (SRBCs) in a plaque-forming cell (PFC) assay. However, the use of slow-release pellets for such studies is limited, as these pellets are only available in fixed doses and similar pellets for kappa and delta agonists have not been developed. In the present study, we investigated the feasibility of administering opioids via Alzet osmotic minipumps to assess their immunomodulatory effects. Groups of mice received minipumps dispensing morphine sulfate, which has primary activity at the mu opioid receptor; U50,488H, which is a kappa-selective agonist; deltorphin II, which is a delta2-selective agonist; or DPDPE, which has greater selectivity for delta1 than delta, receptors. Morphine, U50,488H and deltorphin II were all immunosuppressive, with biphasic dose-response curves exhibiting maximal (approximately 50%) suppression of the PFC response at doses of 0.5 to 2 mg/kg/day 48 h after pump implantation. Further, immunosuppression by morphine sulfate, U50,488H or deltorphin II was blocked by simultaneous implantation of a minipump administering the opioid receptor-selective antagonists CTAP (1 mg/kg/day), nor-binaltorphimine (5 mg/kg/day), or naltriben (3 mg/kg/day), respectively. DPDPE was inactive at doses lower than 10 mg/kg/day. We conclude that osmotic minipumps are a practical and useful way of administering opioids to study their effects on the immune system, and give further evidence that immunosuppression induced in vivo by opioid agonists is mediated not only via mu, but also via kappa and delta2 opioid receptors.

Computational cell biologists snowed in at Cranwell

Cell biology is being inundated by an avalanche of data from the genomics and proteomics enterprises. The complexity and sheer volume of information threaten to overwhelm the ability of traditional cell biologists to grasp its implications and develop experimentally testable hypotheses. For this reason, some have begun to explore computational approaches towards organizing complex data into quantitative models. This requires communication and collaboration between the biological science community and and the physical and mathematical sciences communities. A recent meeting [The First International Symposium on Computational Cell Biology, Cranwell Resort, Lenox, MA, USA; 4-6 March 2001. Organizers: J.H. Carson, A. Cowan, and L.M. Loew (www.nrcam.uchc.edu/conference).] made a first attempt to bring these two communities together. Three feet of new snow fell during the meeting, but the 125 attendees, an unusual mixture of cell biologists, computer scientists, mathematicians, physicists, and engineers, were having too much fun defining the new field of computational cell biology to notice that they were literally snowed in.

Comparison of pharmacological activities of buprenorphine and norbuprenorphine: norbuprenorphine is a potent opioid agonist

Buprenorphine (BUP) is an oripavine analgesic that is beneficial in the maintenance treatment of opiate-dependent individuals. Although BUP has been studied extensively, relatively little is known about norbuprenorphine (norBUP), a major dealkylated metabolite of BUP. We now describe the binding of norBUP to opioid and nociceptin/orphanin FQ (ORL1) receptors, and its effects on [(35)S]guanosine-5'-O-(gamma-thio)triphosphate ([(35)S]GTP gamma S) binding mediated by opioid or ORL1 receptors and in the mouse acetic acid writhing test. Chinese hamster ovary cells stably transfected with each receptor were used for receptor binding and [(35)S]GTP gamma S binding. NorBUP exhibited high affinities for mu-, delta-, and kappa-opioid receptors with K(i) values in the nanomolar or subnanomolar range, comparable to those of BUP. NorBUP and BUP had low affinities for the ORL1 receptor with K(i) values in the micromolar range. In the [(35)S]GTP gamma S binding assay, norBUP displayed characteristics distinct from BUP. At the delta-receptor, norBUP was a potent full agonist, yet BUP had no agonist activity and antagonized actions of norBUP and DPDPE. At mu- and kappa-receptors, both norBUP and BUP were potent partial agonists, with norBUP having moderate efficacy and BUP having low efficacy. At the ORL1 receptor, norBUP was a full agonist with low potency, while BUP was a potent partial agonist. In the writhing test, BUP and norBUP both suppressed writhing in an efficacious and dose-dependent manner, giving A(50) values of 0.067 and 0.21 mg/kg, s.c., respectively. These results highlight the similarities and differences between BUP and norBUP, each of which may influence the unique pharmacological profile of BUP.

The Seasonal Health Questionnaire: a preliminary validation of a new instrument to screen for seasonal affective disorder

BACKGROUND

The main screening tool for Seasonal Affective Disorder (SAD) is the Seasonal Pattern Assessment Questionnaire, but its reliability and validity have been thrown into doubt by several studies.

METHOD

In this study we developed a new questionnaire, the Seasonal Health Questionnaire (SHQ), which is scored by computer to derive the four main operational criteria for diagnosis of SAD. A group of clinically diagnosed SAD patients was contrasted with a group of patients with recurrent non-seasonal depressive disorder using the SPAQ and the SHQ.

RESULTS

The SHQ could be completed without difficulty by patients with long histories of recurrent mood disorder. The SPAQ and the Rosenthal Criteria were the least specific of the criteria for identifying SAD - misclassifying many non-seasonal patients.

CONCLUSIONS

After further development the SHQ may be a more appropriate screening instrument for SAD. The SPAQ should no longer be used for this purpose as it gives misleadingly high estimates of prevalence.

Development and validation of a sensitive analytical method for the simultaneous determination of buprenorphine and norbuprenorphine in human plasma

A sensitive, specific, and robust capillary gas chromatography-mass spectrometry method has been developed and validated for simultaneous determination of buprenorphine and its active metabolite, norbuprenorphine, in human plasma. Sample preparation involved a clean-up procedure using a Bond Elut Certify cartridge followed by derivatization with pentafluoropropionic anhydride. Separation was carried out on a HP-1 fused silica capillary column using helium as the carrier gas. Selected ion monitoring was used in the electron impact mode. Excellent linearity was found between 0.10 and 20.0 ng/ml with a limit of quantitation of 0.05 and 0.10 ng/ml for buprenorphine and norbuprenorphine, respectively. Interday and intraday assay precisions (%CV) and accuracies were within 15.0% for buprenorphine and norbuprenorphine, respectively. Recoveries were quantitative and concentration-independent. This method will be applied to pharmacokinetic/pharmacodynamic/bioequivalence studies of buprenorphine in humans.

Peripheral neural system involvement in hypoalgesic effect of electromagnetic millimeter waves

In a series of blind experiments, using the cold water tail-flick test (cTFT) as a quantitative indicator of pain, the hypoalgesic effect of a single exposure of mice to low power electromagnetic millimeter waves (MW) was studied. The MW exposure characteristics were: frequency = 61.22 GHz; incident power density = 15 mW/cm2; and duration = 15 min. MW treatment was applied to the glabrous skin of the footpad. Exposure of an intact murine paw to the MW resulted in a statistically significant hypoalgesia as measured in the cTFT. These mice were able to resist cold noxious stimulation in the cTFF more than two times longer than animals from the sham-exposed group. A unilateral sciatic nerve transection was used to deafferent the area of exposure in animals from one of the experimental groups. This surgery, conducted six days before the MW treatment, completely abolished the hypoalgesic effect of the exposure to MW. The results obtained support the conclusion that the MW-skin nerve endings interaction is the essential step in the initiation of biological effects caused by MW. Based on our past and present results we recommend that in order to obtain a maximum therapeutic effect, densely innervated skin areas (head, hands) need to be used preferentially for exposure to MW in clinical practice.

Hypoalgesic effect of millimeter waves in mice: dependence on the site of exposure

Based on a hypothesis of neural system involvement in the initial absorption and further processing of the millimeter electromagnetic waves (MW) signal, we reproduced, quantitatively assessed and compared the analgesic effect of a single MW treatment, exposing areas of skin possessing different innervation densities. The cold water tail flick test (cTFT) was used to assess experimental pain in mice. Three areas of exposure were used: the nose, the glabrous skin of the right footpad, and the hairy skin of the mid back at the level of T5-T10. The MW exposure characteristics were: frequency = 61.22 GHz; incident power density = 15mW/cm2; and duration = 15 min. The maximum hypoalgesic effect was achieved by exposing to MW the more densely innervated skin areas--the nose and the footpad. The hypoalgesic effect in the cTFT after MW exposure to the murine back, which is less densely innervated, was not statistically significant. These results support the hypothesis of neural system involvement in the systemic response to MW.

Pain relief caused by millimeter waves in mice: results of cold water tail flick tests

PURPOSE

To find out if millimeter waves can decrease experimental pain response in mice using cold water tail flick test.

MATERIALS AND METHODS

Male Swiss albino mice (15 mice per group) were exposed to continuous millimeter waves at a frequency of 61.22 GHz with incident power densities (IPD) ranging from 0.15 to 5.0 mW/cm2 for 15 min or sham exposed. Latency of tail withdrawal in a cold water (1 +/- 0.5 degrees C) tail flick test was measured before the exposure (baseline) and then four times after the exposure with 15 min breaks.

RESULTS

The mean latency of the tail flick response in mice exposed to millimeter waves was more than twice that of sham-exposed controls (p<0.05). This effect was proportional to the power of millimeter waves and completely disappeared at an IPD level of < or = 0.5 mW/cm2. Pretreatment of mice with the opioid antagonist naloxone (1 mg/kg i.p.) blocked the effect of millimeter waves.

CONCLUSIONS

Results suggest that the antinociceptive effect of millimeter waves is mediated through endogenous opioids.