Determination of tapentadol (Nucynta®) and N-desmethyltapentadol in authentic urine specimens by ultra-performance liquid chromatography-tandem mass spectrometry

Urine specimens from pain management patients dosed with Nucynta (Tapentadol) were confirmed for the presence of tapentadol and N-desmethyltapentadol using ultra-performance liquid chromatography-tandem mass spectrometry to minimize sample preparation and urine volume requirements. The linearity of the method for both tapentadol and N-desmethyltapentadol demonstrated correlation coefficients (R2) above 0.99 and linear ranges from 50 to 500,000 ng/mL for tapentadol and 100 to 500,000 ng/mL for N-desmethyltapentadol. The intraday precision of the assay for both analytes ranged from 2.2 to 6.9% over three concentrations; the interday precision for both analytes ranged from 1.2 to 8.4%. The limits of quantitation were 50 and 100 ng/mL for tapentadol and N-desmethyltapentadol, respectively, and the upper limit of linearity for both analytes was determined to be 500,000 ng/mL. Urine samples were collected within 24 h of dosing with tapentadol and shipped overnight to the laboratory. Samples were hydrolyzed with acid prior to analysis to measure total (unconjugated and conjugated) tapentadol and N-desmethyltapentadol. Further investigation into characterization of metabolites was performed by using a hybrid quadrupole-time-of-flight mass spectrometer in lieu of suitable analytical reference standards. The presence of significant N-desmethyltapentadol glucuronide was demonstrated for the first time.     

Inhibition of nitric oxide synthesis in mouse macrophage cells by feverfew supercritical extract

Feverfew is the most commonly used medicinal herb against migraine headache. The antimigraine mechanism of feverfew supercritical extract was investigated in vitro using the mouse macrophage cell line (RAW 264.7). Mouse macrophage cells were treated with lipopolysaccharide in the presence and absence of feverfew extracts. Inhibition of lipopolysaccharide-induced nitric oxide and TNF-α synthesis were quantified by ELISA. The mRNA and protein expression of iNOS and eNOS genes were analysed by RT-PCR and western blot analysis, respectively. The feverfew extract inhibited both nitric oxide (NO) and TNF-α production in a dose-dependent manner with complete inhibition of NO occurring at 5 μg/mL of feverfew extract. Both eNOS and iNOS mRNA levels were unchanged with the feverfew treatment. However, eNOS and iNOS proteins were significantly down-regulated by the feverfew extract. Feverfew inhibition of NO is due to the down-regulation of both eNOS and iNOS enzymes at the translational and/or post-translational level.     

Multidimensional atomic force microscopy: a versatile novel technology for nanopharmacology research

Nanotechnology is giving us a glimpse into a nascent field of nanopharmacology that deals with pharmacological phenomena at molecular scale. This review presents our perspective on the use of scanning probe microscopy techniques with special emphasis to multidimensional atomic force microscopy (m-AFM) to explore this new field with a particular emphasis to define targets, design therapeutics, and track outcomes of molecular-scale pharmacological interactions. The approach will be to first discuss operating principles of m-AFM and provide representative examples of studies to understand human health and disease at the molecular level and then to address different strategies in defining target macromolecules, screening potential drug candidates, developing and characterizing of drug delivery systems, and monitoring target-drug interactions. Finally, we will discuss some future directions including AFM tip-based parallel sensors integrated with other high-throughput technologies which could be a powerful platform for drug discovery.     

A signature of immune function genes associated with recurrence-free survival in breast cancer patients

The clinical significance of tumor-infiltrating immune cells has been reported in a variety of human carcinomas including breast cancer. However, molecular signature of tumor-infiltrating immune cells and their prognostic value in breast cancer patients remain elusive. We hypothesized that a distinct network of immune function genes at the tumor site can predict a low risk versus high risk of distant relapse in breast cancer patients regardless of the status of ER, PR, or HER-2/neu in their tumors. We conducted retrospective studies in a diverse cohort of breast cancer patients with a 1?C5?year tumor relapse versus those with up to 7?years relapse-free survival. The RNAs were extracted from the frozen tumor specimens at the time of diagnosis and subjected to microarray analysis and real-time RT-PCR. Paraffin-embedded tissues were also subjected to immunohistochemistry staining. We determined that a network of immune function genes involved in B cell development, interferon signaling associated with allograft rejection and autoimmune reaction, antigen presentation pathway, and cross talk between adaptive and innate immune responses were exclusively upregulated in patients with relapse-free survival. Among the 299 genes, five genes which included B cell response genes were found to predict with >85% accuracy relapse-free survival. Real-time RT-PCR confirmed the 5-gene prognostic signature that was distinct from an FDA-cleared 70-gene signature of MammaPrint panel and from the Oncotype DX recurrence score assay panel. These data suggest that neoadjuvant immunotherapy in patients with high risk of relapse may reduce tumor recurrence by inducing the immune function genes.     

Is Lidocaine Infiltration Really Necessary in Micro Ear Surgeries performed Under General Anaesthesia?

To study the role of infiltrating 2% Lidocaine in Micro ear surgeries performed under general anaesthesia. To measure the impact of infiltration of 2% Lidocaine in post operative pain relief and per operative bleeding. A Double blinded, Prospective randomized comparative study was conducted in a tertiary care referral centre. A total of 30 patients planned for micro ear surgeries under general anaesthesia (Tympanoplasty and Cortical mastoidectomy) for CSOM tubotympanic disease were selected and divided into two groups randomly by the chief senior consultant. Group A patients received local infiltration of 2% Lidocaine with one in 200,000 adrenaline and Group B patients received infiltration of one in 200,000 adrenaline in distilled water alone. Operating surgeon assessed the bleeding in the surgical field using Boezaart’s grading system. Post operative pain was assessed using a visual analog scale. Pain scores of these patients were assessed in the 1st, 4 and 24th h post operatively and recorded. The mean post operative pain score in the 1st h for the patients in Group A was 0.93 and for patients in Group B was two. The difference in the pain scores between the two groups was significant (P < 0.02).The difference in the mean post operative pain scores between the two groups in the 4 and 24th h were not significant (P < 0.1).Per operatively, grade III bleeding was present in 73% of patients in group B and only 33% of patients had grade III bleeding in group A. Infiltration of 2% Lidocaine has a significant impact over the grade of bleeding in the operative field and also on 1st h post operative pain relief. It did not have a significant influence on the pain relief in the 4 and 24th h post operatively.