Safety and efficacy of nivolumab plus ipilimumab in patients with advanced renal cell carcinoma with brain metastases: CheckMate 920.

BACKGROUND: Nivolumab plus ipilimumab (NIVO + IPI) has demonstrated long-term efficacy and safety in patients with previously untreated, advanced renal cell carcinoma (aRCC). Although most phase 3 clinical trials exclude patients with brain metastases, the ongoing, multicohort phase 3b/4 CheckMate 920 trial (ClincalTrials.gov identifier NCT02982954) evaluated the safety and efficacy of NIVO + IPI in a cohort that included patients with aRCC and brain metastases, as reported here. METHODS: Patients with previously untreated aRCC and asymptomatic brain metastases received NIVO 3 mg/kg plus IPI 1 mg/kg every 3 weeks × 4 followed by NIVO 480 mg every 4 weeks. The primary end point was the incidence of grade ≥3 immune-mediated adverse events (imAEs) within 100 days of the last dose of study drug. Key secondary end points were progression-free survival and the objective response rate according to Response Evaluation Criteria in Solid Tumors, version 1.1 (both determined by the investigator). Exploratory end points included overall survival, among others. RESULTS: After a minimum follow-up of 24.5 months (N = 28), no grade 5 imAEs occurred. The most common grade 3 and 4 imAEs were diarrhea/colitis (n = 2; 7%) and hypophysitis, rash, hepatitis, and diabetes mellitus (n = 1 each; 4%). The objective response rate was 32% (95% CI, 14.9%-53.5%) with a median duration of response of 24.0 months; 4 of 8 responders remained without reported progression. Seven patients (25%) had intracranial progression. The median progression-free survival was 9.0 months (95% CI, 2.9-12.0 months), and the median overall survival was not reached (95% CI, 14.1 months to not estimable). CONCLUSIONS: In patients who had previously untreated aRCC and brain metastases-a population with a high unmet medical need that often is underrepresented in clinical trials-the approved regimen of NIVO + IPI followed by NIVO showed encouraging antitumor activity and no new safety signals.

The Radiolabeling of a Gly-Sar Dipeptide Derivative with Flourine-18 and Its Use as a Potential Peptide Transporter PET Imaging Agent.

: We have developed a novel fluorine-18 radiotracer, dipeptide 1, radiolabeled in two steps from mesylate 3. The initial radiolabeling is achieved in a short reaction time (10 min) and purified through solid-phase extraction (SPE) with modest radiochemical yields (rcy = 10 ± 2%, n = 5) in excellent radiochemical purity (rcp > 99%, n = 5). The de-protection of the tert-butyloxycarbonyl (Boc) and trityl group was achieved with mild heating under acidic conditions to provide 18F-tagged dipeptide 1. Preliminary analysis of 18F-dipeptide 1 was performed to confirm uptake by peptide transporters (PepTs) in human pancreatic carcinoma cell lines Panc1, BxPC3, and ASpc1, which are reported to express the peptide transporter 1 (PepT1) . Furthermore, we confirmed in vivo uptake of 18F-dipeptide tracer 1 using microPET/CT in mice harboring subcutaneous flank Panc1, BxPC3, and Aspc1 tumors. In conclusion, we have established the radiolabeling of dipeptide 1 with fluoride-18, and demonstrated its potential as an imaging agent which may have clinical applications for the diagnosis of pancreatic carcinomas.

Diagnostic Performance of 4D CT and Sestamibi SPECT/CT in Localizing Parathyroid Adenomas in Primary Hyperparathyroidism.

Background There currently is no consensus on the optimal localization procedure and imaging protocol for parathyroid adenoma. Parathyroid four-dimensional (4D) CT has emerged as a promising method for preoperative localization. Purpose To evaluate the diagnostic performance of parathyroid 4D CT and technetium 99m-sestamibi (hereafter, referred to as sestamibi) SPECT/CT in preoperative localization in patients with primary hyperparathyroidism. Materials and Methods This was a single-institution retrospective study of patients with primary hyperparathyroidism who underwent a combined imaging protocol of sestamibi SPECT/CT and 4D CT (noncontrast, contrast agent-enhanced, arterial, and delayed venous phases) acquired in a single setting from February 2013 to May 2016, with subsequent parathyroidectomy within 6 months. Reference standard for correct localization was on the basis of location denoted on operative reports, with pathologic confirmation of parathyroid adenoma or hyperplasia. By using a four-quadrant analysis, sensitivity, specificity, and area under the curve (AUC) for localization of the hyperfunctioning parathyroid gland or glands at sestamibi SPECT/CT and 4D CT were compared, per modality and in combination. Results Four hundred patients (319 women, 81 men; mean age, 61 years ± 14 [standard deviation]) were evaluated. Similar diagnostic performance was found in both combined 4D CT with sestamibi SPECT/CT and 4D CT alone (area under the curve [AUC], 0.88 [95% CI: 0.86, 0.90] and 0.87 [95% CI: 0.85, 0.90], respectively; P = .82). Both modalities outperformed sestamibi SPECT/CT (AUC, 0.78; 95% CI: 0.76, 0.81; P < .001). Four-dimensional CT showed higher sensitivity than did sestamibi SPECT/CT (sensitivity, 79.3% [414 of 522] vs 58.0% [303 of 522], respectively; P < .001). In a subset analysis, 4D CT had higher sensitivity than sestamibi SPECT/CT in patients with single-gland disease (sensitivity, 92.5% [297 of 321] vs 75.1% [241 of 321], respectively; P < .001) and with multigland disease (sensitivity, 58.2% [117 of 201] vs 30.8% [62 of 201], respectively; P < .001). Conclusion Four-dimensional CT provided superior preoperative localization compared with sestamibi SPECT/CT in patients with single and multigland disease. The combination of the two modalities did not improve diagnostic performance compared with four-dimensional CT alone. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Sinha and Oates in this issue.

Baseline Radiomic Signature to Estimate Overall Survival in Patients With NSCLC.

INTRODUCTION: We aimed to define a baseline radiomic signature associated with overall survival (OS) using baseline computed tomography (CT) images obtained from patients with NSCLC treated with nivolumab or chemotherapy. METHODS: The radiomic signature was developed in patients with NSCLC treated with nivolumab in CheckMate-017, -026, and -063. Nivolumab-treated patients were pooled and randomized to training, calibration, or validation sets using a 2:1:1 ratio. From baseline CT images, volume of tumor lesions was semiautomatically segmented, and 38 radiomic variables depicting tumor phenotype were extracted. Association between the radiomic signature and OS was assessed in the nivolumab-treated (validation set) and chemotherapy-treated (test set) patients in these studies. RESULTS: A baseline radiomic signature was identified using CT images obtained from 758 patients. The radiomic signature used a combination of imaging variables (spatial correlation, tumor volume in the liver, and tumor volume in the mediastinal lymph nodes) to output a continuous value, ranging from 0 to 1 (from most to least favorable estimated OS). Given a threshold of 0.55, the sensitivity and specificity of the radiomic signature for predicting 3-month OS were 86% and 77.8%, respectively. The signature was identified in the training set of patients treated with nivolumab and was significantly associated (p < 0.0001) with OS in patients treated with nivolumab or chemotherapy. CONCLUSIONS: The radiomic signature provides an early readout of the anticipated OS in patients with NSCLC treated with nivolumab or chemotherapy. This could provide important prognostic information and may support risk stratification in clinical trials.

Application of a non-target variable data independent workflow (vDIA) for the screening of prohibited substances in doping control testing.

A non-target variable Data Independent Acquisition (vDIA) workflow based on accurate mass measurements using a Q Exactive OrbiTrap is presented for the first time for equine doping control testing. The vDIA workflow uses a combination of MS1 events (1 to 2) and multiple vDIA events to cover the analytes of interest. The workflow basically captures a digital image of a sample allowing all relevant MS1 and MS2 data to be recorded. In theory, the workflow can accommodate an unlimited number of analytes as long as they are amenable to the sample extraction protocol and fall within the mass limits of the workflow. Additional targets fulfilling the above requirements can be added without changing any settings. The performance of the vDIA workflow was illustrated by applying it to two screening methods in horse urine, with one workflow covering 331 basic drugs and the other covering 45 quaternary ammonium drugs (QADs). Both screening methods have good detection sensitivity with 84% of the basic drugs having Limits of Detection (LoDs) of ≤ 1 ng/mL and 84% of the QADs having LoDs of ≤ 0.4 ng/mL. Other method characteristics including retention reproducibility, method precision and false hit rate will also be presented.

Improvement in patient-reported outcomes in Chinese adults after bariatric surgery: 1-year follow-up of a prospective cohort.

BACKGROUND: Impaired health-related quality of life is commonly observed in patients with obesity who are scheduled for bariatric surgery. However, bariatric surgery tends to improve quality of life physically, with no final conclusion regarding mental domains. OBJECTIVE: To assess changes of patient-reported outcomes in terms of health-related quality of life, depression, anxiety status, and physical activity (PA) after bariatric surgery among patients with obesity. SETTINGS: Queen Mary Hospital, Tung Wah Hospital, and United Christian Hospital, Hong Kong SAR; a longitudinal study. METHODS: A multicenter, prospective, observational cohort study was conducted in Hong Kong between 2017 and 2018. Follow-up interviews at 1, 3, 6, and 12 months postoperatively were administrated via telephone. Short Form-12 Health Survey Version 2, Euroqol 5-dimension-5-level, and Impact of Weight on Quality of Life-Lite were used to assess health-related quality of life. Scores of anxiety and depression were evaluated by Hospital Anxiety and Depression Scale. Walking, moderate, and vigorous metabolic equivalent tasks and PA levels were measured by International Physical Activity Questionnaire-Short Form. Demographic and clinical characteristics, including age, sex, body mass index, and preexisting co-morbidities at baseline were collected. Comparisons of scores were made between baseline and 12 months using paired t test or McNemar test. RESULTS: A total of 25 patients who have received bariatric surgery (laparoscopic sleeve gastrectomy: 96%; laparoscopic gastric bypass: 4%) and 25 control patients matched using propensity scores derived by baseline covariates were involved. Significant improvements were observed in health-related quality of life regarding physical functioning (P < .001), role physical (P = .013), bodily pain (P = .011), general health (P < .011), vitality (P = .029), social functioning (P = .017), and physical composite summary (P < .001) of Short Form-12 Health Survey Version 2 from baseline to follow-up 12 months after surgery. Scores of physical composite summary, mental composite summary, and Short Form-6 D of surgical patients all had an overall upward trend during observation compared with those in the control group. All domains in Impact of Weight on Quality of Life-Lite were significantly higher at 12 months compared with baseline (P = .001 in sexual life domain, P < .001 in other domains). Patients experienced a decrease in depression score of Hospital Anxiety and Depression Scale 12 months after bariatric surgery (P = .026), while anxiety score was not found to differ from baseline (P = .164). No significant differences in total metabolic equivalent tasks (P = .224) and PA levels (P = .180) between baseline and 12-month follow-up were found. CONCLUSION: After 12 months of follow-up, increase in physical quality of life, reduction in depression status and less impairment caused by weight were observed, without significant changes in anxiety score and postoperative PA.

Identification of Non-Small Cell Lung Cancer Sensitive to Systemic Cancer Therapies Using Radiomics.

PURPOSE: Using standard-of-care CT images obtained from patients with a diagnosis of non-small cell lung cancer (NSCLC), we defined radiomics signatures predicting the sensitivity of tumors to nivolumab, docetaxel, and gefitinib. EXPERIMENTAL DESIGN: Data were collected prospectively and analyzed retrospectively across multicenter clinical trials [nivolumab, n = 92, CheckMate017 (NCT01642004), CheckMate063 (NCT01721759); docetaxel, n = 50, CheckMate017; gefitinib, n = 46, (NCT00588445)]. Patients were randomized to training or validation cohorts using either a 4:1 ratio (nivolumab: 72T:20V) or a 2:1 ratio (docetaxel: 32T:18V; gefitinib: 31T:15V) to ensure an adequate sample size in the validation set. Radiomics signatures were derived from quantitative analysis of early tumor changes from baseline to first on-treatment assessment. For each patient, 1,160 radiomics features were extracted from the largest measurable lung lesion. Tumors were classified as treatment sensitive or insensitive; reference standard was median progression-free survival (NCT01642004, NCT01721759) or surgery (NCT00588445). Machine learning was implemented to select up to four features to develop a radiomics signature in the training datasets and applied to each patient in the validation datasets to classify treatment sensitivity. RESULTS: The radiomics signatures predicted treatment sensitivity in the validation dataset of each study group with AUC (95 confidence interval): nivolumab, 0.77 (0.55-1.00); docetaxel, 0.67 (0.37-0.96); and gefitinib, 0.82 (0.53-0.97). Using serial radiographic measurements, the magnitude of exponential increase in signature features deciphering tumor volume, invasion of tumor boundaries, or tumor spatial heterogeneity was associated with shorter overall survival. CONCLUSIONS: Radiomics signatures predicted tumor sensitivity to treatment in patients with NSCLC, offering an approach that could enhance clinical decision-making to continue systemic therapies and forecast overall survival.

Immune Modulation Therapy and Imaging: Workshop Report.

A workshop at the National Cancer Institute on May 2, 2016, considered the current state of imaging in assessment of immunotherapy. Immunotherapy has shown some remarkable and prolonged responses in the treatment of tumors. However, responses are variable and frequently delayed, complicating the evaluation of new immunotherapy agents and customizing treatment for individual patients. Early anatomic imaging may show that a tumor has increased in size, but this could represent pseudoprogression. On the basis of imaging, clinicians must decide if they should stop, pause, or continue treatment. Other imaging technologies and approaches are being developed to improve the measurement of response in patients receiving immunotherapy. Imaging methods that are being evaluated include radiomic methods using CT, MRI, and 18F-FDG PET, as well as new radiolabeled small molecules, antibodies, and antibody fragments to image the tumor microenvironment, immune status, and changes over the course of therapy. Current studies of immunotherapy can take advantage of these available imaging options to explore and validate their use. Collection of CT, PET, and MR images along with outcomes from trials is critical to develop improved methods of assessment.

High throughput screening of sub-ppb levels of basic drugs in equine plasma by liquid chromatography-tandem mass spectrometry.

This paper describes a high throughput LC-MS-MS method for the screening of 75 basic drugs in equine plasma at sub-ppb levels. The test scope covers diversified classes of drugs including some alpha- and beta-blockers, alpha- and beta-agonists, antihypotensives, antihypertensives, analgesics, antiarrhythmics, antidepressants, antidiabetics, antipsychotics, antiulcers, anxiolytics, bronchodilators, CNS stimulants, decongestants, sedatives, tranquilizers and vasodilators. A plasma sample was first deproteinated by addition of trichloroacetic acid. Basic drugs were then extracted by solid-phase extraction (SPE) using a Bond Elut Certify cartridge, and analysed by LC-MS-MS in positive electrospray ionization (+ESI) and multiple reaction monitoring (MRM) mode. Liquid chromatography was performed using a short C(8) column (3.3 cm L x 2.1mm ID with 3 microm particles) to provide fast analysis time. The overall instrument turnaround time was 8 min, inclusive of post-run and equilibration time. No interference from the matrices at the expected retention times of the targeted masses was observed. Over 60% of the drugs studied gave limits of detection (LoD) at or below 25 pg/mL, with some LoDs reaching down to 0.5 pg/mL. The inter-day precision for the relative retention times ranged from 0.01 to 0.54%, and that for the relative peak area ratios (relative to the internal standard) ranged from 4 to 37%. The results indicated that the method has acceptable precision to be used on a day-to-day basis for qualitative identification.

A bottom-up approach in estimating the measurement uncertainty and other important considerations for quantitative analyses in drug testing for horses.

Quantitative determination, particularly for threshold substances in biological samples, is much more demanding than qualitative identification. A proper assessment of any quantitative determination is the measurement uncertainty (MU) associated with the determined value. The International Standard ISO/IEC 17025, "General requirements for the competence of testing and calibration laboratories", has more prescriptive requirements on the MU than its superseded document, ISO/IEC Guide 25. Under the 2005 or 1999 versions of the new standard, an estimation of the MU is mandatory for all quantitative determinations. To comply with the new requirement, a protocol was established in the authors' laboratory in 2001. The protocol has since evolved based on our practical experience, and a refined version was adopted in 2004. This paper describes our approach in establishing the MU, as well as some other important considerations, for the quantification of threshold substances in biological samples as applied in the area of doping control for horses. The testing of threshold substances can be viewed as a compliance test (or testing to a specified limit). As such, it should only be necessary to establish the MU at the threshold level. The steps in a "Bottom-Up" approach adopted by us are similar to those described in the EURACHEM/CITAC guide, "Quantifying Uncertainty in Analytical Measurement". They involve first specifying the measurand, including the relationship between the measurand and the input quantities upon which it depends. This is followed by identifying all applicable uncertainty contributions using a "cause and effect" diagram. The magnitude of each uncertainty component is then calculated and converted to a standard uncertainty. A recovery study is also conducted to determine if the method bias is significant and whether a recovery (or correction) factor needs to be applied. All standard uncertainties with values greater than 30% of the largest one are then used to derive the combined standard uncertainty. Finally, an expanded uncertainty is calculated at 99% one-tailed confidence level by multiplying the standard uncertainty with an appropriate coverage factor (k). A sample is considered positive if the determined concentration of the threshold substance exceeds its threshold by the expanded uncertainty. In addition, other important considerations, which can have a significant impact on quantitative analyses, will be presented.

Doping control analysis of anabolic steroids in equine urine by gas chromatography-tandem mass spectrometry.

Anabolic steroids are banned substances in equine sports. Gas chromatography-mass spectrometry (GC-MS) has been the traditional technique for doping control analysis of anabolic steroids in biological samples. Although liquid chromatography-mass spectrometry (LC/MS) has become an important technique in doping control, the detection of saturated hydroxysteroids by LC-MS remains a problem due to their low ionization efficiency under electrospray. The recent development in fast-scanning gas-chromatography-triple-quadrupole mass spectrometry (GC-MS/MS) has provided a better alternative with a significant reduction in chemical noise by means of selective reaction monitoring. Herein, we present a sensitive and selective method for the screening of over 50 anabolic steroids in equine urine using gas chromatography-tandem mass spectrometry (GC-MS/MS). Copyright © 2016 John Wiley & Sons, Ltd.

Evidence of boldenone, nandrolone, 5(10)-estrene-3ß-17α-diol and 4-estrene-3,17-dione as minor metabolites of testosterone in equine.

The detection of boldenone, nandrolone, 5(10)-estrene-3ß,17α-diol, and 4-estrene-3,17-dione in a urine sample collected from a gelding having been treated with testosterone (500 mg 'Testosterone Suspension 100', single dose, injected intramuscularly) in 2009 led the authors' laboratory to suspect that these 'testicular' steroids could be minor metabolites of testosterone in geldings. Administration trials on six castrated horses with Testosterone Suspension 100 confirmed that low levels of boldenone, nandrolone, 5(10)-estrene-3ß,17α-diol, and 4-estrene-3,17-dione could indeed be detected and confirmed in the early post-administration urine samples from all six geldings. Although boldenone has been reported to be present in urine after testosterone administration, there has been no direct evidence reported that boldenone, nandrolone, 5(10)-estrene-3ß,17α-diol, and 4-estrene-3,17-dione are metabolites of testosterone in geldings. Subsequent in vitro experiments involving the incubation of testosterone with horse liver microsomes, liver, adipose and muscle tissues, and adrenal cortex homogenates failed to provide evidence that these four substances are minor metabolites of testosterone. An administration trial using 'Testosterone Suspension 100' supplemented with 13 C-labelled testosterone (500 mg, 1:1 ratio, injected intramuscularly) was performed. The similarities of the excretion curves of 12 C-testosterone and 13 C-testosterone in urine suggest that there was minimal kinetic isotope effect. 13 C-Labelled boldenone, nandrolone and 4-estrene-3,17-dione were detected but not 5(10)-estrene-3ß,17α-diol and its 13 C-counterpart. This is the first unequivocal evidence of boldenone, nandrolone and 4-estrene-3,17-dione being metabolites of testosterone in geldings. In view of these results, caution should be exercised when interpreting findings of boldenone, nandrolone and/or 4-estrene-3,17-dione together with a relatively high level of testosterone in gelding urine. Copyright © 2017 John Wiley & Sons, Ltd.

Comprehensive screening of anabolic steroids, corticosteroids, and acidic drugs in horse urine by solid-phase extraction and liquid chromatography-mass spectrometry.

This paper reports two highly efficient liquid chromatography-mass spectrometry (LC-MS) methods for the screening of anabolic steroids, corticosteroids, and acidic drugs for the purpose of doping control in equine sports. Sample extraction was performed using a mixed-mode C8-SCX solid-phase extraction (SPE) cartridge. The first eluted fraction (acidic/neutral fraction) was base-washed and the resulting organic extract was used for the screening of anabolic steroids and corticosteroids by LC-MS using multiple reaction monitoring (MRM) in the positive electrospray ionisation (ESI) mode. The remaining aqueous extract was re-adjusted to pH 6 and acidic drugs were recovered by liquid/liquid extraction. Detection was again achieved using LC-MRM but in the negative ESI mode. A total of 40 anabolic steroids and corticosteroids, and over 50 acidic drugs, including some cyclooxygenase-2 (COX-2) inhibitors, oxicams, anti-diabetics, sedatives, diuretics and Delta(9)-tetrahydro-11-norcannabinol-9-carboxylic acid, could be covered by the two LC-MS methods. Both methods utilized a high efficiency reversed-phase column (3.3 cm L x 2.1 mm I.D. with 3 microm particles) coupled with a fast-scanning triple-quadrupole mass spectrometer to achieve fast turnaround times. The overall turnaround times for both methods were 10 min, inclusive of post-run and equilibration times.

Generation of phase II in vitro metabolites using homogenized horse liver.

The successful use of homogenized horse liver for the generation of phase I in vitro metabolites has been previously reported by the authors' laboratory. Prior to the use of homogenized liver, the authors' laboratory had been using mainly horse liver microsomes for carrying out equine in vitro metabolism studies. Homogenized horse liver has shown significant advantages over liver microsomes for in vitro metabolism studies as the procedures are much quicker and have higher capability for generating more in vitro metabolites. In this study, the use of homogenized liver has been extended to the generation of phase II in vitro metabolites (glucuronide and/or sulfate conjugates) using 17ß-estradiol, morphine, and boldenone undecylenate as model substrates. It was observed that phase II metabolites could also be generated even without the addition of cofactors. To the authors' knowledge, this is the first report of the successful use of homogenized horse liver for the generation of phase II metabolites. It also demonstrates the ease with which both phase I and phase II metabolites can now be generated in vitro simply by using homogenized liver without the need for ultracentrifuges or tedious preparation steps.

High-throughput screening of corticosteroids and basic drugs in horse urine by liquid chromatography-tandem mass spectrometry.

This paper describes two high-throughput liquid chromatography-tandem mass spectrometry (LC-MS-MS) methods for the screening of two important classes of drugs in equine sports, namely corticosteroids and basic drugs, at low ppb levels in horse urine. The method utilized a high efficiency reversed-phase LC column (3.3 cm L x 2.1 mm i.d. with 3 microm particles) to provide fast turnaround times. The overall turnaround time for the corticosteroid screen was 5 min and that for the basic drug screen was 8 min, inclusive of post-run and equilibration times. Method specificity was assessed by analysing a total of 35 negative post-race horse urine samples. No interference from the matrices at the expected retention times of the targeted masses was observed. Inter-day precision for the screening of 19 corticosteroids and 48 basic drugs were evaluated by replicate analyses (n = 10) of a spiked sample on 4 consecutive days. The results demonstrated that both methods have acceptable precision to be used on a routine basis. The performance of these two methods on real samples was demonstrated by their applications to drug administration and positive post-race urine samples.

Screening of anabolic steroids in horse urine by liquid chromatography-tandem mass spectrometry.

Anabolic steroids have the capability of improving athletic performance and are banned substances in the Olympic games as well as in horseracing and equestrian competitions. The control of their abuse in racehorses is traditionally performed by detecting the presence of anabolic steroids and/or their metabolite(s) in urine samples using gas chromatography-mass spectrometry (GC-MS). However, this approach usually requires tedious sample processing and chemical derivatisation steps and could be very insensitive in detecting certain steroids. This paper describes a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS) method for the detection of anabolic steroids that are poorly covered by GC-MS. Enzyme-treated urine was processed by solid-phase extraction (SPE) using a Bond Elut Certify cartridge, followed by a base wash for further cleanup. Separation of the steroids was carried out on a reversed-phase DB-8 column using 0.1% acetic acid and methanol as the mobile phase in a gradient elution programme. The mass spectrometer for the detection of the steroids was operated in the positive electrospray ionisation (ESI) mode with multiple reaction monitoring (MRM). Urine samples fortified with 15 anabolic steroids (namely, androstadienone, 1-androstenedione, bolasterone, boldione, 4-estrenedione, gestrinone, methandrostenolone, methenolone, 17alpha-methyltestosterone, norbolethone, normethandrolone, oxandrolone, stenbolone, trenbolone and turinabol) at low ng/mL levels were consistently detected. No significant matrix interference was observed at the retention times of the targeted ion masses in blank urine samples. The method specificity, sensitivity, precision, recoveries, and the performance of the enzyme hydrolysis step were evaluated. The successful application of the method to analyse methenolone acetate administration urine samples demonstrated that the method could be effective in detecting anabolic steroids and their metabolites in horse urine.

In vitro metabolism studies of desoxy-methyltestosterone (DMT) and its five analogues, and in vivo metabolism of desoxy-vinyltestosterone (DVT) in horses.

The positive findings of norbolethone in 2002 and tetrahydrogestrinone in 2003 in human athlete samples confirmed that designer steroids were indeed being abused in human sports. In 2005, an addition to the family of designer steroids called 'Madol' [also known as desoxy-methyltestosterone (DMT)] was seized by government officials at the US-Canadian border. Two years later, a positive finding of DMT was reported in a mixed martial arts athlete's sample. It is not uncommon that doping agents used in human sports would likewise be abused in equine sports. Designer steroids would, therefore, pose a similar threat to the horseracing and equestrian communities. This paper describes the in vitro metabolism studies of DMT and five of its structural analogues with different substituents at the 17α position (RH, ethyl, vinyl, ethynyl and 2 H3 -methyl). In addition, the in vivo metabolism of desoxy-vinyltestosterone (DVT) in horses will be presented. The in vitro studies revealed that the metabolic pathways of DMT and its analogues occurred predominantly in the A-ring by way of a combination of enone formation, hydroxylation and reduction. Additional biotransformation involving hydroxylation of the 17α-alkyl group was also observed for DMT and some of its analogues. The oral administration experiment revealed that DVT was extensively metabolised and the parent drug was not detected in urine. Two in vivo metabolites, derived respectively from (1) hydroxylation of the A-ring and (2) di-hydroxylation together with A-ring double-bond reduction, could be detected in urine up to a maximum of 46 h after administration. Another in vivo metabolite, derived from hydroxylation of the A-ring with additional double-bond reduction and di-hydroxylation of the 17α-vinyl group, could be detected in urine up to a maximum of 70 h post-administration. All in vivo metabolites were excreted mainly as glucuronides and were also detected in the in vitro studies. Copyright © 2015 John Wiley & Sons, Ltd.

Control of the misuse of testosterone in castrated horses based on an international threshold in plasma.

Testosterone is an endogenous steroid produced primarily in the testes. Trace levels of testosterone are found in urine samples from geldings, as testosterone is also secreted by the adrenal. An international threshold of free and conjugated testosterone in urine (20 ng/mL) was adopted by the International Federation of Horseracing Authorities (IFHA) in 1996 for controlling testosterone misuse in geldings. In view of the recent popularity of using blood in doping control testing, it is necessary to establish a threshold for testosterone in gelding plasma. A liquid chromatography-mass spectrometry (LC/MS) method was developed for quantifying low levels of free testosterone in gelding plasma. Based on a population study of 152 post-race plasma samples, the mean ± SD concentration of plasma testosterone was determined to be 14.7 ± 6.8 pg/mL. Normal distribution could be obtained after square-root or cube-root transformation, resulting in respective tentative thresholds of 49 or 55 pg/mL (corresponding to a risk factor of less than 1 in 10 000). A rounded-up threshold of 100 pg/mL of free testosterone in plasma was proposed. Based on the administration of Testosterone Suspension 100 to six geldings, the same average detection time of 14 days was observed in either plasma or urine using the proposed plasma threshold and the existing international urine threshold. The maximum detection time was 18 days in plasma and 20 days in urine. The results demonstrated the proposed plasma threshold is effective in controlling the misuse of testosterone in geldings. Similar results were subsequently obtained in Europe, and this proposed threshold was adopted by IFHA in October 2013.

Imaging of diabetic foot infections.

Complications from diabetic foot infections are a leading cause of nontraumatic lower-extremity amputations. Nearly 85% of these amputations result from an infected foot ulcer. Osteomyelitis is present in approximately 20% of diabetic foot infections. It is imperative that clinicians make quick and successful diagnoses of diabetic foot osteomyelitis (DFO) because a delay in treatment may lead to worsening outcomes. Imaging studies, such as plain films, bone scans, musculoskeletal ultrasound, computerized tomography scans, magnetic resonance imaging, and positron emission tomography scans, aid in the diagnosis. However, there are several mimickers of DFO, which present problems to making a correct diagnosis.