Characterization of bilateral trigeminal constriction injury using an operant facial pain assay

In order to better understand and treat neuropathic pain, scientific study must use methods that can assess pain processing at the cortical level where pain is truly perceived. Operant behavior paradigms can accomplish this. We used an operant task to evaluate changes following chronic constriction injury to the trigeminal nerves. We also relate these behavioral changes to immunohistochemistry of transient receptor potential channels vanilloid 1 and melastatin 8 (TRPV1 and TRPM8) in the trigeminal ganglia. Following nerve injury, successful performance of the operant task was reduced and aversive behaviors were observed with 10 and 37 °C stimulation, indicating cold allodynia and mechanical allodynia respectively. In contrast, while aversive behaviors were observed with 48 °C stimulation, successful performance of the operant task was not substantially hindered following injury. These behavioral changes were accompanied by an increase in TRPV1 positive cells and an increased intensity of TRPM8 staining at 2 weeks post-injury, when cold allodynia is maximal. These findings suggest that the incorporation of operant behavioral assessment in the study of pain may provide insight into the relationship among peripheral changes, motivational drive, and pain. Understanding this relationship will allow us to better treat and prevent chronic neuropathic pain.

Mesalazine (5-aminosalicylic acid) alters faecal bacterial profiles, but not mucosal proteolytic activity in diarrhoea-predominant irritable bowel syndrome

BACKGROUND

Imbalances in gut luminal bacteria may contribute to the pathogenesis of irritable bowel syndrome (IBS).

AIM

To explore select bacteriological and anti-inflammatory effects of mesalazine (mesalamine; 5-aminosalicylic acid or 5ASA) and their relation to potential therapeutic effects in IBS.

METHODS

Prospective pilot study of 12 women with diarrhoea-predominant IBS. Patients received oral mesalazine (1.5 g b.d.) for 4 weeks followed by a 4-week washout phase. Molecular profiling of stool bacterial communities and IBS symptoms were assessed before, during and after mesalazine treatment. Colonic mucosal biopsies were assessed for proteolytic activity. Qualitative and quantitative effects of mesalazine on stool microbiota, mucosal proteolytic activity and IBS symptoms were assessed.

RESULTS

Faecal bacteria decreased by 46% on mesalazine treatment (P = 0.014), but returned to baseline during washout. Firmicutes and Bacteroidetes represented 95% of identified phylotypes, with a trend towards an increase in the proportion of Firmicutes at week 4 in symptomatic responders [median (IQR) 14% (49) increase] compared with nonresponders [median 5% (11) decrease, P = 0.088]. Rectosigmoid mucosal proteolytic activity did not change between baseline and treatment [median 23.2 (17.9) vs. 19.5 (46.7) mU activity/mg tissue, P = 0.433]. Eight of 12 (67%) patients responded favourably to mesalazine based on a global relief questionnaire, with significant decreases in days with discomfort and increases in bowel movement satisfaction.

CONCLUSIONS

Mesalazine treatment is associated with a decrease in faecal bacteria abundance and rebalancing of the major constituents of the microbiota. Further study of the bacteriological and anti-inflammatory properties of mesalazine in IBS is warranted.

Loading and skeletal development and maintenance

Mechanical loading is a major regulator of bone mass and geometry. The osteocytes network is considered the main sensor of loads, through the shear stress generated by strain induced fluid flow in the lacuno-canalicular system. Intracellular transduction implies several kinases and phosphorylation of the estrogen receptor. Several extra-cellular mediators, among which NO and prostaglandins are transducing the signal to the effector cells. Disuse results in osteocytes apoptosis and rapid imbalanced bone resorption, leading to severe osteoporosis. Exercising during growth increases peak bone mass, and could be beneficial with regards to osteoporosis later in life, but the gain could be lost if training is abandoned. Exercise programs in adults and seniors have barely significant effects on bone mass and geometry at least at short term. There are few data on a possible additive effect of exercise and drugs in osteoporosis treatment, but disuse could decrease drugs action. Exercise programs proposed for bone health are tedious and compliance is usually low. The most practical advice for patients is to walk a minimum of 30 to 60 minutes per day. Other exercises like swimming or cycling have less effect on bone, but could reduce fracture risk indirectly by maintaining muscle mass and force.

Bortezomib plus modified R-CHOP as initial therapy for indolent B-cell lymphomas: Phase I results

8577

Background: Adding rituximab (R) to chemotherapy improves survival for patients (pts) with follicular lymphoma (FL) and other indolent non-Hodgkin lymphomas (NHL), but not all pts respond. Bortezomib (B) + RCHOP has a high complete response (CR) rate, but higher doses of B with standard vincristine produced severe neuropathy. We developed a phase I/II trial to test if adding B to RCHOP with modified vincristine dosing can be well-tolerated and yield a high CR rate. Methods: Untreated pts with indolent NHL and indications for treatment based on GELF criteria or FLIPI ≥3 received R 375mg/m2, cyclophosphamide 750mg/m2, doxorubicin 50mg/m2, vincristine 1.4mg/m2 (capped at 1.5mg) on day 1, B 1.0- 1.6mg/m2 days 1 and 8, and prednisone 100mg days 1–5 for 6–8 cycles. The maximum tolerated dose (MTD) was defined as the regimen at which <30% grade ≥3 non-hematological or grade ≥4 hematological toxicity (>14 days) occurs. Dose escalation used the Escalation with Overdose Control Bayesian method with upper bound (θ=0.3). This facilitated MTD finding with fewer pts given prior data on B+RCHOP. Functional Assessment of Cancer Therapy (FACT) Neurotoxicity (11-item; 4 point scale), EMG, nerve conduction velocity and epidermal nerve fiber density measures were taken at baseline and after cycle 4. Results: 11 pts with FL (n=6) or other indolent NHL enrolled in phase I. Median age was 59 years (range 29–69). 6 pts (55%) had stage IV disease; 8 (64%) had FLIPI ≥2. Pts received RCHOP + B at 1.0 mg/m2 (n=1), 1.3 mg/m2 (n= 6) or 1.6 mg/m2 (n= 4) and together completed 67 cycles. Treatment was well tolerated. Neuropathy occurred in 4 pts (36%), with 2 grade 1, 1 grade 2 and 1 grade 3 toxicity ( Table ). Grade 4 neutropenia occurred in 4 pts (36%), but none >14 days. Overall response rate was 100% with 5/8 finished pts (63%) achieving CR. 3 continue on treatment. Mean FACT Neurotoxicity after cycle 4 remained < 1 for all items. Conclusions: Adding bortezomib to RCHOP produces limited toxicity when vincristine is capped at 1.5 mg. Phase II will explore the efficacy of this regimen.

[Table: see text]

[Table: see text]

A phase I MMRC clinical trial testing the combination of bortezomib and tipifarnib in relapsed/refractory multiple myeloma

8597

Background: Preclinical work from our group has demonstrated that the combination of a farnesyl transferase inhibitor and bortezomib results in enhanced plasma cell apoptosis, and more recently, we have suggested that the mechanism for this synergy is due to inhibition of HDAC6, and inhibition of the proteasome and aggresome pathway. Methods: Patients with relapsed or refractory myeloma were treated with bortezomib at 1.0 or 1.3 mg/m2 on a standard schedule in conjunction with escalating doses of tipifarnib (100–400mg/BID) given on days 2–15 every 21 days. Dose escalation was accomplished using an adaptive phase I design (Escalation With Overdose Control). Results: 22 patients have been enrolled, of which 18 are evaluable, into respective tipifarnib dose levels 100 mg (n=6), 200mg (n=5) and 300mg (n=5) and 400mg (n=2). Median age for the enrolled patients is 59 and median time from myeloma diagnosis was 4.7 years. The average number of prior therapies was 4.5. Among these patients with advanced myeloma and refractory disease, stabilization of disease or better was seen among 8/10 patients with 2 of the 8 achieving an MR. Among the patients achieving clinical benefit, 1 patient had a stable M-protein, but experienced an 80% reduction in circulating plasma cells while on therapy, and another has had a 75% reduction in the free light chain assay. The most common drug related side effect was was Gr2 diarrhea (23.5%). Hematologic toxicities were difficult to ascertain as patients had advanced myeloma and many were entered onto study with platelet counts between 25 and 50. Additional grade 3 toxicities included renal insufficiency (related to PD), pneumonia and altered mental status which were all considered not related to study drug but to progression of disease. There were no Grade 3-5 drug related toxicities. One patient experienced grade 2 peripheral neuropathy who did not have pre existing PN at baseline. Conclusions: The combination of bortezomib and tipifarnib is supported by preclinical rationale and has produced stable disease or better among 10 of 18 patients with refractory myeloma. Optimal dose of tipifarnib and bortezomib have yet to be defined, and additional patients are being enrolled with 1.3mg/m2 of bortezomib, and escalating doses of tipifarnib.

[Table: see text]

Epizootic Ameloblastomas in Chinook Salmon (Oncorhynchus tshawytscha) of the Northwestern United States

Abnormal growths were observed on the lips and in the oral cavities of 2- and 3-year-old Chinook salmon (Oncorhynchus tshawytscha) maintained in one freshwater and one saltwater captive fish-rearing facility in the Columbia River (Pacific Northwest). Initially presenting as bilaterally symmetrical, red, irregular plaques on oral mucosal surfaces, the lesions developed progressively into large, disfiguring masses. Of the 502 natural parr collected for captive broodstock, 432 (86%) displayed these tumors, whereas cohort salmon (i.e., same year classes) in these same facilities remained unaffected. Morphologically similar neoplasms were collected occasionally from adult Chinook salmon that had returned to their natal streams. Histologic features of the tumors suggested that they were derived from the portion of dental lamina destined to form tooth root sulci; therefore, these neoplasms were diagnosed as ameloblastomas. The lesions also resembled archived specimens of Chinook salmon oral tumors, which had been described decades earlier. Etiologic investigations performed during the current outbreak included bacteriologic, virologic, genetic, ultrastructural analyses, and cohabitation exposure studies. Results of these efforts did not indicate an obvious genetic basis for this syndrome, attempts to isolate potentially causative viruses or bacteria were negative, and disease transmission to naïve fish was unsuccessful. A few intracytoplasmic hexagonal structures, possibly consistent with viral particles (∼100 nm), were observed ultrastructurally in a tumor cell from 1 of 6 specimens submitted for transmission electron microscopy. Although the presence of these particles does not constitute sufficient evidence for causality, an infectious or multifactorial etiology seems plausible.

Airborne particulate matter exposure and urinary albumin excretion: the Multi-Ethnic Study of Atherosclerosis

OBJECTIVES

Understanding mechanistic pathways linking airborne particle exposure to cardiovascular health is important for causal inference and setting environmental standards. We evaluated whether urinary albumin excretion, a subclinical marker of microvascular function which predicts cardiovascular events, was associated with ambient particle exposure.

METHODS

Urinary albumin and creatinine were measured among members of the Multi-Ethnic Study of Atherosclerosis at three visits during 2000-2004. Exposure to PM(2.5) and PM(10) (microg/m(3)) was estimated from ambient monitors for 1 month, 2 months and two decades before visit one. We regressed recent and chronic (20 year) particulate matter (PM) exposure on urinary albumin/creatinine ratio (UACR, mg/g) and microalbuminuria at first examination, controlling for age, race/ethnicity, sex, smoking, second-hand smoke exposure, body mass index and dietary protein (n = 3901). We also evaluated UACR changes and development of microalbuminuria between the first, and second and third visits which took place at 1.5- to 2-year intervals in relation to chronic PM exposure prior to baseline using mixed models.

RESULTS

Chronic and recent particle exposures were not associated with current UACR or microalbuminuria (per 10 microg/m(3) increment of chronic PM(10) exposure, mean difference in log UACR = -0.02 (95% CI -0.07 to 0.03) and relative probability of having microalbuminuria = 0.92 (95% CI 0.77 to 1.08)) We found only weak evidence that albuminuria was accelerated among those chronically exposed to particles: each 10 microg/m(3) increment in chronic PM(10) exposure was associated with a 1.14 relative probability of developing microalbuminuria over 3-4 years, although 95% confidence intervals included the null (95% CI 0.96 to 1.36).

CONCLUSIONS

UACR is not a strong mechanistic marker for the possible influence of air pollution on cardiovascular health in this sample.

Sildenafil citrate improves erectile function: a randomised double-blind trial with open-label extension

AIMS

To evaluate once-daily 100-mg sildenafil for the treatment of erectile dysfunction (ED) in men with ED and lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH).

METHODS

This was a 12-week, randomised, double-blind, placebo-controlled (DBPC) trial, with an 8-week open-label (OL) extension, in men > or = 45 years of age who scored < or = 25 on the erectile function (EF) domain of the International Index of Erectile Function (IIEF) and > or = 12 on the International Prostate Symptom Score.

RESULTS

At DBPC end of treatment (EOT), the sildenafil group (n = 189, vs. placebo, n = 180) had improved EF (IIEF), improved emotional well-being [Self-Esteem And Relationship questionnaire (SEAR)], and greater treatment satisfaction (Erectile Dysfunction Inventory of Treatment Satisfaction) (p < 0.0001). At OL EOT, IIEF and SEAR scores improved slightly in the group previously randomised to sildenafil (n = 168), but much more in the group previously randomised to placebo (N = 155), such that total improvement over the 20-week trial was comparable between the groups. Erections at baseline were hard enough for penetration on approximately half of occasions and lasted long enough for successful intercourse on less than one quarter of occasions, increasing at sildenafil DBPC and OL EOT to approximately 90% (penetration) and 80% (intercourse success) vs. 61% (penetration) and 39% (intercourse success) for DBPC placebo. At sildenafil DBPC and OL EOT, > or = 90% of men were taking sildenafil 100 mg. Sildenafil was generally well tolerated.

CONCLUSIONS

In this trial of men with ED and BPH-associated LUTS, sildenafil treatment for ED was efficacious, effective and generally well tolerated.

Feasibility study of capecitabine (cap) and cisplatin (cis) with radiation therapy (RT) in the management of patients with locally advanced unresectable squamous cell carcinoma of the head and neck (HNSCC)

16520

Background: Concurrent chemoradiation has become the standard of care for locally advanced unresectable HNSCC. The most commonly used chemotherapy is cis and 5-fluorouracil (5-FU). We evaluated the feasibility of using cap and cis during RT in this population. Cap is an oral pro-drug of 5-FU that can be given daily with RT in order to enhance the activity of RT. Methods: Between Oct, 2003 and Sept, 2005, 12 male patients aged 46–83 were treated at the VA Medical Center. Patients received cis 100 mg/m2 on days 1 and 29 and cap 450 mg/m2 bid (2 hours prior to RT and 12 hours later) for 5 days of each week concurrent with RT to a total dose of 70 Gy in 35 fractions over 7 weeks. Primary endpoint of the study was toxicity. Results: All 12 patients were able to complete therapy. Treatment delays and/or dose modifications were needed in 7 patients. Treatment related toxicities included 6 patients with grade 3 mucositis and 5 patients with grade 3 dysphagia. Other grade 3 toxicities included 3 patients with dehydration and 1 patient each with leucopenia, constipation, nausea and vomiting, and odynophagia. Percutaneous gastrostomy (PEG) tubes were required in 5 patients. Complete response to chemoradiation was seen in 9 patients, 2 patients obtained partial response, and 1 patient progressed. Median progression free and overall survivals have not been reached with a median follow-up of 21 months. Conclusions: Cis and cap administered concurrently with RT has manageable toxicities and is active in patients with locally advanced unresectable HNSCC.

No significant financial relationships to disclose.

Release of biologically active CD154 during collection and storage of platelet concentrates prepared for transfusion

BACKGROUND

Millions of platelet transfusions are given each year. Transfusion reactions occur in as many as 30% of patients receiving unmodified platelet transfusions. The cause of some transfusion reactions remains unclear. The current paradigm suggests that platelet concentrates (PC) contain proinflammatory mediators that are released by white blood cells during collection, processing and storage. CD154 (CD40 ligand, CD40L) is a potent inflammatory mediator, normally sequestered inside the resting platelet, that is known to translocate to the platelet membrane and be shed into plasma in response to agonist activation. We hypothesized that platelet-soluble CD154 (sCD154) is 'spontaneously' released by transfused platelets and plays a major role in transfusion reactions.

OBJECTIVES

To determine the time course and biological properties of CD154 translocation and release during collection and storage of platelets for transfusion.

METHODS

We measured surface and sCD154 in platelets prepared by the platelet-rich plasma method or apheresis by fluorescence-activated cell sorting and enzyme-linked immunosorbent assay, respectively. The specific biological activity of platelet sCD154 was assayed by stimulation of the CD154/CD40 pathway in known CD40-positive cells with PC-derived supernatants.

RESULTS AND CONCLUSIONS

We demonstrate that PCs prepared for transfusion have high levels of membrane-bound CD154 and sCD154, with maximum levels being seen 72 h after platelet collection. Importantly, we show that platelet-derived sCD154 potently stimulates CD40-positive cells. We propose that platelet-derived CD154 is a key 'cytokine' responsible for adverse reactions associated with platelet transfusions. Improved methods of platelet collection and/or storage, which limit CD154 expression, could reduce the risks of transfusion reaction.

Size matters: gastric pouch size correlates with weight loss after laparoscopic Roux-en-Y gastric bypass

BACKGROUND

Over the past 20 years, there has been an ongoing discussion about the importance of gastric pouch size as a key factor influencing weight loss after bariatric surgery. This analysis aimed to determine the relationship between initial gastric pouch size and excess weight loss (EWL) after laparoscopic Roux-en-Y gastric bypass (LRYGB).

METHODS

Between August 2002 and March 2005, 320 LRYGB were performed at Yale New Haven Hospital. The patients' demographics were entered into a longitudinal, prospective database. Upper gastrointestinal series were routinely performed on postoperative day 1. Pouch size was measured as area (cm2) on an anteroposterior radiograph at maximum pouch distention. Linear regression analysis was performed to determine the association between pouch size and weight loss at 6 and 12 months postoperatively. Adjustments were made for age, gender, and preoperative body mass index (BMI).

RESULTS

The mean age of the patients was 41.2 years. Of the 320 study patients, 261 were women (81.6%) and 59 were men (18.4%). The mean preoperative BMI was 51.1 kg/m2; the mean 6-month EWL was 50.5%; the mean 12-month EWL was 62.5%; and the mean pouch size was 63.9 cm2. A statistically significant, negative correlation between pouch size and EWL was found at 6 months (beta = -0.241; p < 0.01) and at 12 months (beta = -0.302; p < 0.02). The findings show that male gender (beta = 0.147; p < 0.04) and preoperative BMI (beta = 0.190; p < 0.01) are positively correlated with pouch size.

CONCLUSION

The analysis demonstrates that initial gastric pouch size is not the only significant component for successful weight loss after LRYGB. Male gender and increased preoperative BMI were identified as factors predicting pouch size. Efforts to standardize small pouch size for all patients seems important to the success of surgical therapy for morbid obesity.

Recent exposure to particulate matter and C-reactive protein concentration in the multi-ethnic study of atherosclerosis

Ambient levels of particulate matter have been linked to cardiovascular disease. The mechanisms mediating these associations are poorly understood. One candidate mechanism is inflammation. Using data from the Multi-Ethnic Study of Atherosclerosis (2000-2002), the authors investigated the relation between exposure to particulate matter of less than or equal to 2.5 microm in diameter (PM2.5) and C-reactive protein concentration in 5,634 persons aged 45-84 years who were free of cardiovascular disease. Data from US Environmental Protection Agency monitors were used to estimate PM2.5 exposures for the prior day, prior 2 days, prior week, prior 30 days, and prior 60 days. Only the 30-day and 60-day mean exposures showed a weak positive association with C-reactive protein, and confidence intervals were wide: relative increases in C-reactive protein per 10 microg/m3 of PM2.5 adjusted for person-level covariates were 3% (95% confidence interval (CI): -2, 10) for a 30-day mean and 4% (95% CI: -3, 11.0) for a 60-day mean. The means of 7-day, 30-day, and 60-day exposures were weakly, positively, and nonsignificantly associated with the odds of C-reactive protein of greater than or equal to 3 mg/liter: adjusted odds ratios were 1.05 (95% CI: 0.96, 1.15), 1.12 (95% CI: 0.98, 1.29), and 1.12 (95% CI: 0.96, 1.32), respectively. Slightly stronger associations were observed in persons without other risk factors for elevated C-reactive protein, but this heterogeneity was not statistically significant. The authors' results are not compatible with strong effects of particulate matter exposures on population levels of C-reactive protein.

A rational approach to androgen therapy for hypogonadal men with prostate cancer

With earlier detection and improved survival from early stage prostate cancer, it is likely that the numbers of men presenting with hypogonadal symptoms following curative surgery for their cancer will increase. Although testosterone supplementation is effective in improving symptoms of hypogonadism, traditionally such therapy has been contraindicated in patients who have had prostate cancer. This paper reviews the evidence that testosterone therapy can be safely given to selected men with hypogonadism who have had prostate cancer but currently have no evidence of disease by clinical and prostate-specific antigen (PSA) criteria. Such patients should be treated cautiously and followed closely.