Simultaneous pharmacokinetic and pharmacodynamic analysis of 5α-reductase inhibitors and androgens by liquid chromatography tandem mass spectrometry

AbstractBenign prostatic hyperplasia and prostate cancer can be treated with the 5α-reductase inhibitors, finasteride and dutasteride, when pharmacodynamic biomarkers are useful in assessing response. A novel method was developed to measure the substrates and products of 5α-reductases (testosterone, 5α-dihydrotestosterone (DHT), androstenedione) and finasteride and dutasteride simultaneously by liquid chromatography tandem mass spectrometry, using an ABSciex QTRAP® 5500, with a Waters Acquity™ UPLC. Analytes were extracted from serum (500µL) via solid-phase extraction (Oasis® HLB), with 13C3-labelled androgens and d9-finasteride included as internal standards. Analytes were separated on a Kinetex C18 column (150×3mm, 2.6µm), using a gradient run of 19min. Temporal resolution of analytes from naturally occurring isomers and mass +2 isotopomers was ensured. Protonated molecular ions were detected in atmospheric pressure chemical ionisation mode and source conditions optimised for DHT, the least abundant analyte. Multiple reaction monitoring was performed as follows: testosterone (m/z 289→97), DHT (m/z 291→255), androstenedione (m/z 287→97), dutasteride (m/z 529→461), finasteride (m/z 373→317). Validation parameters (intra- and inter-assay precision and accuracy, linearity, limits of quantitation) were within acceptable ranges and biological extracts were stable for 28 days. Finally the method was employed in men treated with finasteride or dutasteride; levels of DHT were lowered by both drugs and furthermore the substrate concentrations increased

How common are foot problems among individuals with diabetes? Diabetic foot ulcers in the Dutch population.

Aims/hypothesis Contemporary data on diabetic foot ulcer prevalence are scarce. Most studies w ere conducted in the 1990s, reporting incidence rates of 1.9–2.6%. Since then the revalence of diabetes has doubled and the organisation of diabetes care has undergone major changes. Up-to-date data that quantify the occurrence of diabetic foot ulcers are required and could serve as baseline measures for future studies. Methods Individuals with diabetes (n = 81,793) were identified from the NIVEL (Netherlands institute for health services research) Primary Care Database, which contains data for standardised routine care and is representative of the Dutch population. The annual incidence rates of ulcers and other foot abnormalities were calculated using data collected between 2010 and 2013. To account for inaccuracies, incidence rates were calculated using: (1) only individuals with a documented foot examination; (2) all individuals; and (3) individuals with explicit documentation of present/absent foot ulceration. Results There were 412 individuals with documented ulceration during the registration period (0.50%). The annual incidence rate of foot ulcers was 0.34% (range 0.22–1.08%). Of those individuals with a documented foot examination, 14.6% had absent pedal pulsations, 17.3% had neuropathy and 10.1% had callus/pressure marks. Conclusions/interpretation The annual incidence rate of foot ulcers in the current study was lower than previously reported. This observation could reflect the efficacy of screening practices and an increased awareness among professionals and patients. Nevertheless, approximately one in every five diabetic individuals had at least one identifiable risk factor on foot examination. This signifies the importance of preventive screening. (aut. ref.

Sensor based time budgets in commercial Dutch dairy herds vary over lactation cycles and within 24 hours

Cows from 8 commercial Dutch dairy farms were equipped with 2 sensors to study their complete time budgets of eating, rumination, lying, standing and walking times as derived from a neck and a leg sensor. Daily sensor data of 1074 cows with 3201 lactations was used from 1 month prepartum until 10 months postpartum. Farms provided data over a 5 year period. The final models (lactational time budget and 24h time budget) showed significant effects of parity, farm and calving season. When primiparous cows were introduced in the lactational herd, they showed a decrease in lying time of 215 min (95% CI: 187–242) and an increase in standing time of 159 min (95% CI: 138–179), walking time of 23 min (95% CI: 20–26) and rumination time of 69 min (95% CI: 57–82). Eating time in primiparous cows increased from 1 month prepartum until 9 months in lactation with 88 min (95% CI: 76–101) and then remained stable until the end of lactation. Parity 2 and parity 3+ cows decreased in eating time by 30 min (95% CI: 20–40) and 26 min (95% CI: 18–33), respectively, from 1 month before to 1 month after calving. Until month 6, eating time increased 11 min (95% CI: 1–22) for parity 2, and 24 min (95% CI: 16–32) for parity 3+. From 1 month before calving to 1 month after calving, they showed an increase in ruminating of 17 min (95% CI: 6–28) and 28 min (95% CI: 21–35), an increase in standing time of 117 min (95% CI: 100–135) and 133 min (95% CI: 121–146), while lying time decreased with 113 min (95% CI: 91–136) and 130 min (95% CI: 114–146), for parity 2 and 3+, respectively. After month 1 in milk to the end of lactation, lying time increased 67 min (95% CI: 49–85) for parity 2, and 77 min (95% CI: 53–100) for parity 3+. Lactational time budget patterns are comparable between all 8 farms, but cows on conventional milking system (CMS) farms with pasture access appear to show higher standing and walking time, and spent less time lying compared to cows on automatic milking system (AMS) farms without pasture access. Every behavioral parameter presented a 24h pattern. Cows eat, stand and walk during the day and lie down and ruminate during the night. Daily patterns in time budgets on all farms are comparable except for walking time. During the day, cows on CMS farms with pasture access spent more time walking than cows on AMS farms without pasture access. The average 24h pattern between parities is comparable, but primiparous cows spent more time walking during daytime compared to older cows. These results indicate a specific behavioral pattern per parameter from the last month prepartum until 10 months postpartum with different patterns between parities but comparable patterns across farms. Furthermore, cows appear to have a circadian rhythm with varying time budgets in the transition period and during lactation

Increased risk for chronic comorbid disorders in patients with inflammatory arthritis: a population based study

Background: Studies determining the development of a wide variety of different comorbid disorders in inflammatory arthritis (IA) patients are scarce, however, this knowledge could be helpful in optimising preventive care in IA patients. The aim of this study is to establish the risk that new chronic comorbid disorders in newly diagnosed patients with IA in a primary care setting are developed. Methods. This is a nested-case-control study from 2001-2010 using data from electronic medical patient records in general practice. In total, 3,354 patients with newly diagnosed IA were selected. Each patient was matched with two control patients of the same age and sex in the same general practice. The development of 121 chronic comorbid disorders of index and control patients was compared using Cox regression. Results: After a median follow-up period of 2.8 years, 56% of the IA-patients had developed at least one chronic comorbid disorder after the onset of IA, compared to 46% of the control patients (p < 0.05). The most frequent developed comorbid disorders after the onset of IA were of cardiovascular (23%), and musculoskeletal (17%) origin. The highest hazard ratios (HRs) were found for anaemia (HR 2.0 [95% CI: 1.4-2.7]) osteoporosis (HR 1.9 [1.4-2.4]), and COPD (HR 1.8 [1.4-2.3]). Conclusion: Patients with IA developed more chronic comorbid disorders after the onset of IA than one might expect based on age and sex. Since comorbidity has a large impact on the disease course, quality of life, and possibly on treatment itself, prevention of comorbidity should be one of the main targets in the treatment of IA patients. © 2013Ursum et al.; licensee BioMed Central Ltd

Rapid and simple neurotoxin-based distinction of Chinese and Japanese star anise by direct plant spray mass spectrometry

Ingestion of products containing Chinese star anise (Illicium verum) fruits contaminated or adulterated with Japanese star anise (Illicium anisatum) fruits can cause poisoning due to the neurotoxin anisatin that is present in Japanese star anise. Thus a rapid, simple and unambiguous distinction between the morphologically similar Chinese star anise and toxic Japanese star anise fruits is important for guaranteeing food safety. After adding ~200 µL of methanol to one star anise carpel placed at 7–10 mm from the inlet of a mass spectrometer and applying a potential of ~5 kV to the carpel, an electrospray is created. The formation of the electrospray is immediate, robust and stable and lasts for at least a minute. The presence or absence of anisatin could be monitored by orbitrap high resolution mass spectrometry (HRMS) in negative mode by observing the [M-H]- ion at m/z 327.1074 (C15H19O8) or in positive mode the [M+K]+ ion at m/z 367.079 (C15H20KO8). Several parameters like wetting solvent, voltage, distance and set-up were optimised. The anisatin signal was ~250 times higher in Japanese than in Chinese star anise. An existing Direct Analysis in Real Time (DART) HRMS for anisatin was used for benchmarking. Alternatively a linear ion trap mass spectrometer could be used in negative selective reaction monitoring (SRM) mode albeit with lower selectivity than the HRMS method. The transition of the [M-H]- ion at m/z 327 to the fragment at m/z 265 was monitored. Direct plant spray and DART ionisation are both robust and provided the same yes/no answer in seconds without any prior sample preparation. Compared with the DART-HRMS procedure, the direct plant spray method is simpler in terms of equipment, yields a more stable signal, does not require heating of the sample but is slightly less selective and requires working with high voltages

Associations between body condition score, locomotion score, and sensor-based time budgets of dairy cattle during the dry period and early lactation

Lameness, one of the most important disorders in the dairy industry, is related to postpartum diseases and has an effect on dairy cow welfare, leading to changes in cows' daily behavioral variables. This study quantified the effect of lameness on the daily time budget of dairy cows in the transition period. In total, 784 multiparous dairy cows from 8 commercial Dutch dairy farms were visually scored on their locomotion (score of 1–5) and body condition (score of 1–5). Each cow was scored in the early and late dry period as well as in wk 4 and 8 postpartum. Cows with locomotion scores 1 and 2 were grouped together as nonlame, cows with score 3 were considered moderately lame, and cows with scores 4 and 5 were grouped together as severely lame. Cows were equipped with 2 types of sensors that measured behavioral parameters. The leg sensor provided number of steps, number of stand-ups (moving from lying to standing), lying time, number of lying bouts, and lying bout length. The neck sensor provided eating time, number of eating bouts, eating bout length, rumination time, number of rumination bouts, and rumination bout length. Sensor data for each behavioral parameter were averaged between 2 d before and 2 d after locomotion scoring. The percentage of nonlame cows decreased from 63% in the early dry period to 46% at 8 wk in lactation; this decrease was more severe for cows with higher parity. Cows that calved in autumn had the highest odds for lameness. Body condition score loss of >0.75 point in early lactation was associated with lameness in wk 4 postpartum. Moderately lame cows had a reduction of daily eating time of around 20 min, whereas severely lame cows had a reduction of almost 40 min. Similarly, moderately and severely lame dry cows showed a reduction of 200 steps/d, and severely lame cows in lactation showed a reduction of 600 steps/d. Daily lying time increased by 26 min and lying bout length increased by 8 min in severely lame cows compared with nonlame cows. These results indicate a high prevalence of lameness on Dutch dairy farms, with an increase in higher locomotion scores from the dry period into early lactation. Time budgets for multiparous dairy cows differed between the dry period and the lactating period, with a higher locomotion score (increased lameness) having an effect on cows' complete behavioral profile. Body condition score loss in early lactation was associated with poor locomotion postpartum, whereas lameness resulted in less eating time in the dry period and early lactation, creating a harmful cycle.</p

Prevalence of the causative agents of equine piroplasmosis in the South West of The Netherlands and the identification of two autochthonous clinical Theileria equi infections

Equine piroplasmosis (EP) has not been considered indigenous in The Netherlands. However, following the detection of an apparently indigenous subclinical Babesia caballi infection in a horse on Schouwen- Duiveland (an island in the Zeeland Province), a survey was undertaken between May and September 2010 to assess the prevalence of the causative agents of EP in the South-West of The Netherlands. Blood samples from 300 randomly selected horses were tested for specific antibodies against Theileria equi and B. caballi using an indirect fluorescence antibody test (IFAT), and for parasite DNA using a specific polymerase chain reaction combined with reverse line blotting (PCR-RLB). Twelve of the horses (4%) were seropositive for EP. Of these, nine (75%) were positive (titreP1:160) for B. caballi alone and three (25%) were also positive for T. equi. PCR-RLB detected T. equi DNA in five horses (1.6%), two of which were seronegative. Four (1.3%) of the positive horses (three positive for T. equi and one for both B. caballi and T. equi) were considered truly indigenous. During the study, two indigenous ponies from a farm situated outside the sampling area were diagnosed with acute clinical piroplasmosis characterized by severe anaemia and pyrexia. Blood smears showed T. equi – like inclusions in red blood cells, and T. equi infection was confirmed in both ponies by PCR-RLB. The initial subclinical B. caballi infection, the survey results and the two acute clinical EP cases confirmed the autochthonous transmission of B. caballi and T. equi infections in The Netherlands.This research was partly funded by the Dutch Ministry of Agriculture.http://www.elsevier.com/locate/tvjlab201