Background
Dental caries and enamel defects (DDE) are prevalent amongst children. The presence of DDE, especially enamel hypomineralization, may increase caries experience. The reported prevalence of ...hypomineralized second primary molars (HSPM) is 2.7–21.8%, although the occurrence in Australian children remains unknown. These HSPM represent a potential predictive factor for molar‐incisor hypomineralization (MIH).
Methods
In total, 623 children aged 3–5 years from 30 randomly selected kindergartens participated. The HSPM were recorded using an index combining the European Academy of Paediatric Dentistry MIH Judgment Criteria and modified DDE Index. Caries was recorded using International Caries Detection and Assessment System criteria.
Results
In total, 144 HSPM were observed in 88 of the 623 (14.1%) children, a tooth‐level prevalence of 5.8%. The prevalence of dentinal carious lesions was 13.2%, and caries prevalence (d2–6mft > 0) was 36.4%. Cavitated carious lesions affected 30.7% of HSPM.
Conclusions
The relationship between an increase in HSPM lesion extent and increasing number of HSPM per child was statistically significant. A positive association between HSPM severity and extent at tooth level existed (P < 0.05). There was a positive relationship between the extent of HSPM and carious lesion severity (P < 0.05). In this population, children with HSPM did not have overall greater caries experience.
Using three- and four-body decays of \(D\) mesons produced in semileptonic \(b\)-hadron decays, precision measurements of \(D\) meson mass differences are made together with a measurement of the ...\(D^{0}\) mass. The measurements are based on a dataset corresponding to an integrated luminosity of \(1.0 fb^{-1}\) collected in \(pp\) collisions at 7\,TeV. Using the decay \(D^0 \rightarrow K^{+} K^{-} K^{-} \pi^{+}\), the \(D^0\) mass is measured to be \(M(D^0) &=& 1864.75 \pm 0.15 \,({\rm stat}) \pm 0.11 \,({\rm syst}) \, \textrm{MeV/c^2}\). The mass differences \(M(D^{+}) - M(D^{0}) = 4.76 \pm 0.12 \,({\rm stat}) \pm 0.07 \,({\rm syst}) \, \textrm{MeV/c^2}\) and \(M(D^{+}_s) - M(D^{+}) = 98.68 \pm 0.03 \,({\rm stat}) \pm 0.04 \,({\rm syst}) \, \textrm{MeV/c^2}\) are measured using the \(D^0 \rightarrow K^{+} K^{-} \pi^{+} \pi^{-}\) and \(D^{+}_{(s)} \rightarrow K^{+}K^{-} \pi^{+}\) modes.
The intestinal efflux transporter breast cancer resistance protein (BCRP) restricts the absorption of rosuvastatin. Of the transporters important to rosuvastatin disposition, fostamatinib inhibited ...BCRP (IC50 = 50 nM) and organic anion-transporting polypeptide 1B1 (OATP1B1; IC50 > 10 μM), but not organic anion transporter 3, in vitro, predicting a drug-drug interaction (DDI) in vivo through inhibition of BCRP only. Consequently, a clinical interaction study between fostamatinib and rosuvastatin was performed (and reported elsewhere). This confirmed the critical role BCRP plays in statin absorption, as inhibition by fostamatinib resulted in a significant 1.96-fold and 1.88-fold increase in rosuvastatin area under the plasma concentration-time curve (AUC) and Cmax, respectively. An in vitro BCRP inhibition assay, using polarized Caco-2 cells and rosuvastatin as probe substrate, was subsequently validated with literature inhibitors and used to determine BCRP inhibitory potencies (IC50) of the perpetrator drugs eltrombopag, darunavir, lopinavir, clopidogrel, ezetimibe, fenofibrate, and fluconazole. OATP1B1 inhibition was also determined using human embryonic kidney 293-OATP1B1 cells versus estradiol 17β-glucuronide. Calculated parameters of maximum enterocyte concentration Igut max, maximum unbound hepatic inlet concentration, transporter fraction excreted value, and determined IC50 value were incorporated into mechanistic static equations to compute theoretical increases in rosuvastatin AUC due to inhibition of BCRP and/or OATP1B1. Calculated theoretical increases in exposure correctly predicted the clinically observed changes in rosuvastatin exposure and suggested intestinal BCRP inhibition (not OATP1B1) to be the mechanism underlying the DDIs with these drugs. In conclusion, solitary inhibition of the intestinal BCRP transporter can result in clinically significant DDIs with rosuvastatin, causing up to a maximum 2-fold increase in exposure, which may warrant statin dose adjustment in clinical practice.
That the employment rate appears to respond to changes in trend growth is an enduring macroeconomic puzzle. This paper shows that, in the presence of a return to experience, a slowdown in ...productivity growth raises reservation wages, thereby lowering aggregate employment. The paper develops new evidence that shows this mechanism is important for explaining the growth-employment puzzle. The combined effects of changes in aggregate wage growth and returns to experience account for all the increase from 1968 to 2006 in nonemployment among low-skilled men and for approximately half the increase in nonemployment among all men.
To determine the protein expression of TNFAIP3 in synovium and to show the capability of 6q23 intergenic SNPs, associated with rheumatoid arthritis (RA) susceptibility, to influence TNFAIP3 gene ...transcription.
Immunohistochemistry for TNFAIP3, NF-kB p65 and phosphorylated NF-kB p65 protein expression was performed in 6 RA knee joint synovium samples compared to 9 osteoarthritis (OA) samples. Luciferase reporter gene assays were used to examine the regulatory ability of RA associated SNP variants on TNFAIP3 promoter activity. Sense and antisense constructs were prepared for rs6920220 alleles, together with each of the 4 SNPs in r2=1 with it (rs6933404, rs2327832, rs6927172 and rs17264332), coupled to the TNFAIP3 promoter. Transient transfections were performed in a human T lymphoblastoid (CEMC7A) cell line. Bioinformatic software was utilised to prioritise SNPs for further investigation. Electrophoretic mobility shift assays (EMSA), using CEMC7A nuclear extracts, were conducted for the rs6927172 SNP alleles.
TNFAIP3 protein expression was seen in the synovium samples and differential TNFAIP3 protein expression between RA vs. OA synoviocytes observed. Within RA synoviocytes TNFAIP3 expression is predominately cytoplasmic, whereas in OA its expression is strongly nuclear and cytoplasmic. For 3 of the 5 SNPs investigated (rs6920220, rs6933404, rs6927172) evidence of repressor activity of TNFAIP3 transcription was seen and EMSA data showed evidence of differential transcription factor binding to rs6927172 alleles.
This is the first observation of TNFAIP3 protein expression in RA and OA synovium. In vitro analysis of 6q23 intergenic SNPs supports the possibility of the functional regulation of TNFAIP3.
Background and objectives
Fostamatinib is a spleen tyrosine kinase inhibitor that has been investigated as therapy for rheumatoid arthritis and immune thrombocytopenic purpura. The present studies ...assessed the potential for pharmacokinetic interaction between fostamatinib and the commonly prescribed medications oral contraceptive (OC), warfarin, and statins (rosuvastatin, simvastatin) in healthy subjects.
Methods
The OC study was a crossover study over two 28-day treatment periods (Microgynon
®
30 plus placebo or fostamatinib). Concentrations of OC constituents (ethinyl estradiol/levonorgestrel) were measured. Effects on warfarin pharmacokinetics and pharmacodynamics were assessed (21-day study). Warfarin was administered on days 1 and 14, fostamatinib on days 8–20. The statin study was a two-period, fixed-sequence study of the effects of fostamatinib on exposure to rosuvastatin or simvastatin (single doses). Safety was assessed throughout.
Results
Fostamatinib co-administration with OC increased exposure to ethinyl estradiol area under the plasma concentration–time curve at steady state (AUC
ss
) 28 % confidence interval (CI 90 %) 21–36; maximum plasma concentration (
C
max
) at steady state (
C
max,ss
) 34 % (CI 26–43), but not levonorgestrel (AUC
ss
5 %;
C
max,ss
−3 %), while exposure to luteinizing hormone and follicle-stimulating hormone decreased (≈20 %). Fostamatinib did not affect the pharmacokinetics/pharmacodynamics of warfarin to a clinically relevant extent, but caused an upward trend in AUC for both
R
- and
S
-warfarin 18 % (CI 13–23) and 13 % (CI 7–19). Fostamatinib increased rosuvastatin AUC by 96 % (CI 78–115) and
C
max
by 88 % (CI 69–110), and increased simvastatin acid AUC by 74 % (CI 50–102) and
C
max
by 83 % (CI 57–113).
Conclusion
Fostamatinib exhibits drug–drug interactions when co-administered with OC, simvastatin, or rosuvastatin, with the AUC of statins almost doubling. Fostamatinib did not exhibit a clinically relevant DDI on warfarin.
Abstract Purpose Fostamatinib, a spleen tyrosine kinase inhibitor and prodrug of the active metabolite R406, is being developed as an anti-inflammatory drug for several indications for which ...polypharmacy is likely. Digoxin, indicated for congestive cardiac failure, may be used for certain supraventricular dysrhythmias. The studies reported herein examined whether fostamatinib and R406 are inhibitors of P-glycoprotein (P-gp) in vitro and evaluated the effect of fostamatinib on the pharmacokinetic parameters of digoxin to understand drug–drug interaction (DDI) potential in the clinic. Methods Inhibition of P-gp–mediated digoxin transport by fostamatinib and R406 was determined across Caco-2 cell monolayers. Apparent permeability of digoxin was determined and used to calculate efflux ratios and percentage inhibition. Half maximal inhibitory concentrations (IC50 ) and theoretical gastrointestinal concentration I2 (dose in moles per 250 mL) were calculated to gauge clinical DDI potential. In a subsequent Phase I study, the plasma concentration–time profiles and resulting pharmacokinetic parameters were examined across 2 treatment periods: (1) oral digoxin loading dose of 0.25 mg BID on day 1 and 0.25 mg once daily on days 2 to 8, and (2) oral digoxin 0.25 mg once daily and oral fostamatinib 100 mg BID on days 9 to 15. Findings Fostamatinib (but not R406) was determined to be a P-gp inhibitor in vitro (IC50 = 3.2 μM). On the basis of a theoretical gastrointestinal concentration (I2 )/IC50 ratio of 216 (I2 = 691 μM), predictions indicated the potential for absorption-based DDI in vivo through inhibition of intestinal P-gp. In the clinical study, when digoxin was co-administered with fostamatinib, digoxin levels were higher before dosing and throughout the dosing interval, and an increase in exposure to digoxin was observed. Co-administration led to a 1.70-fold increase in digoxin maximum plasma concentration at steady state (Cmax,ss ) versus digoxin administration alone (2.18 vs 1.32 ng/mL). Median digoxin time of Cmax was earlier when digoxin was co-administered with fostamatinib (1.00 vs 1.48 hours). The digoxin AUC during the dosing interval at steady state was increased 1.37-fold with co-administration. No severe or serious adverse events or deaths were reported. Implications Fostamatinib was confirmed to be a P-gp inhibitor in vitro and in vivo, and a DDI with digoxin was apparent. Co-administration of digoxin and fostamatinib was generally well tolerated. However, continued review of digoxin response and dose is advisable should these agents be prescribed concomitantly. ClinicalTrials.gov identifier: NCT01355354.
1. An understanding of the role that transporters, in particular P-glycoprotein (P-gp), can play in the absorption, distribution, metabolism and excretion (ADME) of candidate drugs, and an assessment ...of how these processes might impact on toxicity and the potential for drug-drug interactions in the clinic, is required to support drug development and registration. It is therefore necessary to validate preclinical assays for the in vitro evaluation of candidate drugs as substrates or inhibitors of human P-gp.
2. The present study has characterized a Caco-2 cell monolayer model by determining the bi-directional apparent permeabilities and efflux ratios of the known P-gp substrates (3H-digoxin, 3H-ketoconazole, 3H-verapamil, 3H-quinidine, dipyridamole and loratidine; 1-100 µM) a non-substrate (3H-propranolol; 10 µM), or by determining the inhibitory potencies (IC50) of inhibitors (verapamil, ketoconazole, quinidine, dipyridamole and probenecid; 0.1-100 µM) on the basolateral-to-apical transport of 3H-digoxin (5 µM), in order to validate methodologies for the identification of substrates or inhibitors of P-gp, respectively.
3. The reproducibility of the 3H-digoxin or verapamil data determined from replicate monolayers across different cell passages indicates that the functional expression of P-gp is consistent across the range of passages (25-40) utilized for transport experiments and that the determination of bi-directional apparent permeability, or IC50 for inhibition of P-gp, respectively, need only be performed on one occasion for a test compound. 3H-digoxin and 3H-propranolol or verapamil and probenecid were considered to be appropriate positive and negative controls of P-gp-mediated transport, or inhibition of P-gp, respectively, to ensure performance of the assays when assessing candidate drugs. Additionally, the low IC50 values determined for ketoconazole and quinidine indicated that these inhibitors were suitable to use to confirm the role of P-gp in the efflux of a test compound.
4. These validated Caco-2 assays are robust, reproducible and suitable for routine in vitro evaluation of candidate drugs. They have been successfully applied to development projects resulting in the identification of two candidate drugs as substrates and inhibitors of P-gp, whereas a third was neither a substrate nor an inhibitor of this transporter.
The transcription factor NF‐E2‐related factor 2 (Nrf2) plays an essential role in the mammalian response to chemical and oxidative stress through induction of hepatic phase II detoxification enzymes ...and regulation of glutathione (GSH). Enhanced liver damage in Nrf2‐deficient mice treated with acetaminophen suggests a critical role for Nrf2; however, direct evidence for Nrf2 activation following acetaminophen exposure was previously lacking. We show that acetaminophen can initiate nuclear translocation of Nrf2 in vivo, with maximum levels reached after 1 hour, in a dose dependent manner, at doses below those causing overt liver damage. Furthermore, Nrf2 was shown to be functionally active, as assessed by the induction of epoxide hydrolase, heme oxygenase‐1, and glutamate cysteine ligase gene expression. Increased nuclear Nrf2 was found to be associated with depletion of hepatic GSH. Activation of Nrf2 is considered to involve dissociation from a cytoplasmic inhibitor, Kelch‐like ECH‐associated protein 1 (Keap1), through a redox‐sensitive mechanism involving either GSH depletion or direct chemical interaction through Michael addition. To investigate acetaminophen‐induced Nrf2 activation we compared the actions of 2 other GSH depleters, diethyl maleate (DEM) and buthionine sulphoximine (BSO), only 1 of which (DEM) can function as a Michael acceptor. For each compound, greater than 60% depletion of GSH was achieved; however, in the case of BSO, this depletion did not cause nuclear translocation of Nrf2. In conclusion, GSH depletion alone is insufficient for Nrf2 activation: a more direct interaction is required, possibly involving chemical modification of Nrf2 or Keap1, which is facilitated by the prior loss of GSH. (HEPATOLOGY 2004;39:1267–1276.)
We evaluated harbor porpoise (Phocoena phocoena (Linnaeus, 1758)) strandings in the Salish Sea to determine calving seasonality (1980–2015). A total of 443 strandings were analyzed, of which 134 were ...calves and 53 were neonates. Stranded calves were reported every month, but peaked in July, August, and September. Based on fetal size and an estimated fetal growth rate of 80 mm/month, mean (±SD) conception date (and range) was back-calculated to 11 October ± 30 days (16 August – 31 December) and was later than in most other studies. Using mean (±SD) length at birth (80 ± 5.8 cm), gestation was estimated to be approximately 10.8 months. Estimated birthing period was 16 July – 27 November, with a mean (±SD) birth date of 10 September (±30.7 days) and a birth length of 80.0 cm. Estimated pregnancy rate (0.28–0.29) is lower than reported in other areas and is likely an underestimate due to missed early embryos, poor postmortem condition of a large proportion of the stranded adult females, and potential biases related to the animals that strand and are available. This study of harbor porpoise reproduction and calving in the Salish Sea is the first assessment of calving seasonality for this species in the northeast Pacific Ocean.
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