T2* relaxometry mapping of the uterine zones

BACKGROUND

Previous literature demonstrated that the T2* value of the uterine junctional zone was lower than that of peripheral myometrium by using BOLD MR imaging. We expect T2* mapping image may add more information to T2-weighted images of the uterine myometrium.

PURPOSE

To evaluate whether T2* mapping software would reproduce the result of previous report, and to apply the software to benign uterine diseases.

MATERIAL AND METHODS

Five healthy volunteers and 19 patients clinically suspected of having benign pelvic disease were imaged using a 1.5T MR system. All women were of reproductive age, and all provided informed consent. Sagittal T2* images using a multishot EPI sequence were obtained. T2* values were calculated and color T2* maps reconstructed using a T2* fitting tool.

RESULTS

The uterine zones could be identified in all 24 examinations on the T2* maps. In addition, a thin "4th zone" was seen between the endometrium and the JZ (junctional zone) in 19 of 24 examinations. The T2* value of JZ was significantly lower than that of peripheral myometrium (PM) (P < 0.001). No significant difference in the T2* value of the JZ or of PM was noted between normal uterus and uterus with leiomyomas and/or adenomyosis.

CONCLUSION

A quantitative T2* map can easily be obtained using the PRIDE software T2* fitting tool, and the software reproduces the result from previous report. T2* value of the junctional zone was lower than that of peripheral myometrium regardless of having benign myometrial diseases.

GPR40-induced insulin secretion by the novel agonist TAK-875: first clinical findings in patients with type 2 diabetes

AIM

Free fatty acids act as signalling molecules for modulating insulin secretion, and their insulinotropic effects are glucose-dependent and mediated through G protein-coupled receptor 40 (GPR40). This mechanism is a potential target for new treatments for managing diabetes. In this study, we present the first clinical data for TAK-875, a novel highly selective, orally bioavailable GPR40 agonist, in Japanese patients with type 2 diabetes insufficiently controlled by diet or exercise therapy.

METHODS

This was an exploratory phase II, multicentre, randomized, double-blind, parallel group study comparing the efficacy and tolerability of TAK-875 100 and 400 mg, and placebo, all administered once daily for 2 weeks.

RESULTS

After 2 weeks of treatment, TAK-875 produced marked glucose lowering effects in a 75 g oral glucose tolerance test (OGTT) as evidenced by mean ± SE intergroup differences in plasma glucose AUC(0-3 h) of -12.98 ± 1.48 (p < 0.0001) and -8.12 ± 1.49 mmol·h/l (p < 0.0001), for TAK-875 400 mg vs. placebo and TAK-875 100 mg vs. placebo, respectively, and 2 h plasma glucose [-4.95 ± 0.71 (p < 0.0001) and -3.21 ± 0.71 mmol/l (p < 0.0001), respectively]. This was accompanied by a significant increase in insulin AUC(0-3 h) [34.68 ± 12.16 (p < 0.01) and 31.49 ± 12.20 (p < 0 · 05) µIU·h/ml, respectively]. Improvement in glycaemic profile was mirrored by a significant change in fasting plasma glucose [-2.37 ± 0·27 (p < 0.0001) and -1.88 ± 0.27 mmol/l (p < 0.0001), respectively]. No cases of hypoglycaemia were observed despite the significant reduction in plasma glucose.

CONCLUSIONS

These exploratory findings provide evidence of the glucose-dependent insulinotropic potential of the GPR40 agonist TAK-875, and the promising clinical changes support future longer term clinical investigation.

Evaluation of cervical myelopathy using apparent diffusion coefficient measured by diffusion-weighted imaging

BACKGROUND AND PURPOSE

Intramedullary high signal intensity on T2-weighted imaging was frequently observed in patients with CSM, although this finding does not well correlate with severity or prognosis of CSM. Instead of this nonquantitative information, another measure for CSM is desired. The work was focused primarily on assessing the relationships between ADC values and clinical and radiologic severity for the diagnosis of CSM.

MATERIALS AND METHODS

The relationship between ADC values measured in the spinal cord at 322 intervertebral levels of 66 patients and clinical factors were analyzed.

RESULTS

ADC values in the spinal cord significantly increased with the degree of spinal cord compression and decreased with time after decompression surgery. Patients with higher ADC values had lower preoperative JOA scores and tended to show poorer clinical recovery.

CONCLUSIONS

ADC values appear to indicate the severity of spinal cord compression and clinical recovery after decompression surgery, so spondylotic myelopathy may partly be predicted preoperatively by using ADC values.

CYP4F2 gene polymorphism as a contributor to warfarin maintenance dose in Japanese subjects

WHAT IS KNOWN AND OBJECTIVE

Polymorphisms in the gene encoding CYP4F2 may partly explain the variability in warfarin maintenance dose by altering the metabolism of vitamin K. To determine the genetic factors that cause large inter-patient variability in warfarin efficacy, we investigated the relationship between serum warfarin concentration and CYP4F2 V433M (1347C>T, rs2108622) polymorphism in Japanese subjects.

METHODS

Gene variations in VKORC1, CYP2C9 and CYP4F2 were analysed in 126 Japanese patients treated with warfarin. The daily dosage of warfarin, concentration of S- and R-warfarin in plasma, and prothrombin time international normalized ratio (PT-INR) was used as the pharmacokinetic and pharmacodynamic indices.

RESULTS AND DISCUSSION

The maintenance dose of warfarin was larger in the CYP4F2 1347 CT genotype group (3·59±1·80 mg/day, P=0·027) than in the CYP4F2 CC genotype group (2·88±1·00 mg/day). CYP4F2 1347C>T polymorphism significantly affected serum R-warfarin concentration when the VKORC1-1639 genotypes are AG and GG.

WHAT IS NEW AND CONCLUSION

Although a significant inter-patient difference in warfarin maintenance dose was observed between the CYP4F2 CC and CT genotypes, serum S-warfarin concentration was not significantly different between them. An effect of CYP4F2 V433M polymorphism on warfarin maintenance dose was observed but was relatively small when compared to the effects of CYP2C9 and VKOR polymorphism.

Unenhanced fat fraction ratios obtained by MR and enhanced T2* values with liver-specific MR contrast agents for diagnosis of non-alcoholic steatohepatitis in rats

BACKGROUND

Non-invasive MR imaging is expected to be used for accurate diagnosis and quantification of non-alcoholic steatohepatitis (NASH), because NASH is a progressive fatty liver disease. New MR techniques, such as fat fraction ratio (FFR) and T2* value measurement, have attracted an increasing attention, because those techniques can measure quantitative parameters of fibrosis, fat and iron deposition in the liver.

PURPOSE

To investigate the potential of FFR and T2* value in NASH with pre-enhancement, gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) or super-paramagnetic iron oxide (SPIO)-enhanced MRI.

MATERIAL AND METHODS

Twenty-eight rats were divided equally into four groups (one control group and three NASH groups). All rats underwent unenhanced, Gd-EOB-DTPA, and SPIO-enhanced MRI. The T2* value of the liver was measured for each image sequence, and then changes in T2* values before and after each injection were analyzed using Dunnett's test. The reduction rate of T2* value before and 13 min after injection of Gd-EOB-DTPA or SPIO was analyzed using Mann-Whitney's U test. Moreover, FFR of the liver was measured before enhancement, and the relationship between fat fraction and the calculated fat area percentage on a pathological specimen was examined using Spearman's correlation test.

RESULTS

On pre-enhancement, FFR and T2* value were 26.0% ± 12.0% and 21.5 ± 4.2 ms for all NASH groups, and 0.9% ± 0.5% and 30.8 ±-5.5 ms for control, respectively. Both FFR and T2* values were significantly different between the NASH and control groups. The reduction rate of T2* value was significantly lower in the NASH groups than in the control group on SPIO-enhanced MRI, though there was no significant difference on Gd-EOB-DTPA-enhanced MRI. FFR was correlated with the calculated fat area percentage for the pathological specimen.

CONCLUSION

Pre-enhancement FFR, T2* value measurement and reduction rate of T2* value on SPIO-enhanced MRI may help estimate the progress of liver fat deposition and fibrosis in NASH.

Impact of Severe Coronary Disease Associated or Not Associated with Diabetes Mellitus on Outcome of Interventional Treatment Using Stents: Results from HERZ (Heart Research Group of Kanazawa) Analyses

Percutaneous coronary intervention (PCI) using a drug-eluting stent (DES) leads to less re-stenosis than PCI using a bare metal stent (BMS), however there is still controversy whether use of a DES for severe coronary disease leads to an acceptable outcome in patients with diabetes mellitus (DM). In this study 8159 lesions were treated in 6739 patients (mean age 68.9 years) with coronary artery disease. Use of a DES significantly decreased the re-stenosis rate compared with BMS in both DM (9.6% versus 21.3%) and non-DM (9.5% versus 17.1%) patients. The re-stenosis rate was significantly higher in DM than in non-DM patients in the BMS group but not in the DES group. There was no statistically significant difference in event-free survival after stenting of patients with left main coronary artery (LMCA) disease between the BMS and DES groups. It was concluded that, compared with BMS, DES reduced re-stenosis in patients with DM, however, we advise careful treatment after using DES for severe coronary disease, including LMCA lesions, in patients with DM.

Rosiglitazone and pioglitazone inhibit estrogen synthesis in human granulosa cells by interfering with androgen binding to aromatase

The effects of rosiglitazone or pioglitazone (thiazolidinediones, TZDs) on estrogen production and aromatase activity in human ovarian cells were examined. Human granulosa cells were incubated in the tissue culture medium supplemented with androstenedione or testosterone, with or without insulin, TZDs, or type 1 17β-hydroxysteroid-dehydrogenase (17β-HSD) inhibitor. Estrogen concentrations in the conditioned medium, aromatase mRNA and protein expression in the cells and androgen substrate binding to aromatase were measured. With androstenedione as substrate, rosiglitazone or pioglitazone inhibited estrone production by up to 22% (p<0.012) while type 1 17β-HSD inhibitor enhanced this effect of rosiglitazone or pioglitazone by 37% (p<0.001) and by 67% (p<0.001), respectively. With testosterone as substrate, rosiglitazone or pioglitazone inhibited estradiol production by 32% (p<0.001). With (3)H-testosterone as substrate, rosiglitazone or pioglitazone inhibited the (3)H-tritiated water release by the cultured cells by 45% and 35%, respectively, thus directly demonstrating inhibition of aromatase. Rosiglitazone or pioglitazone, however, had no significant effect on aromatase mRNA or protein expression. Rosiglitazone or pioglitazone inhibited (125)I-androstenedione and (125)I-testosterone binding to aromatase by 38% (p<0.001). It was concluded that rosiglitazone or pioglitazone inhibit estrogen synthesis in human granulosa cells by interfering with androgen binding to aromatase.

Influence of CYP2C9 and vitamin k oxide reductase complex (VKORC)1 polymorphisms on time to determine the warfarin maintenance dose

Polymorphisms in cytochrome P450 (CYP) 2C9 and the vitamin K oxide reductase complex subunit 1 (VKORC1) greatly affect the maintenance dose of warfarin. To prevent adverse events, immediate dose adjustment is required. The purpose of this study was to investigate the influence of these polymorphisms on the time taken to determine the warfarin maintenance dose for individual patients, and to assess the advantages of genotype-based dosing on initial anticoagulant therapy. We analyzed the genotypes of CYP2C9 and VKORC1 from 72 patients. The number of days taken to determine the maintenance dose was compared with the genotypes. The time taken to determine the maintenance dose of warfarin in group A (CYP2C9*1/*1, VKORC1 -1639AA), B (*1/*1, - 1639GA), C (*1/*3, - 1639AA), and D (*1/*3, - 1639GA) patients was 19 +/- 19, 28 +/- 28, 27 +/- 20 and 7 days, respectively. We analyzed the relationship between the initial dose of warfarin and the number of days required to determine the maintenance dose based on the VKORC1 genotypes. Patients with the VKORC1 - 1639AA genotype and who were initially treated with more than 3mg warfarin, required approximately 2 weeks for the maintenance dose to be determined. Patients with the VKORC1 - 1639GA genotype and the same initial warfarin dosage required approximately a month; however, patients initially treated with 5 mg of warfarin only required 9.5 +/- 5.3 days. We found a tendency that the time taken to determine the warfarin maintenance dose depends on the genotypes. Genotype-based dosing may improve initial anticoagulant therapy.

A transmembrane protein EIG121L is required for epidermal differentiation during early embryonic development

Epidermal differentiation in the ventral ectoderm of Xenopus embryos is regulated by the bone morphogenetic protein (BMP) pathway. However, it remains unclear how the BMP pathway is activated and induces the epidermal fate in the ventral ectoderm. Here, we identify a novel player in the BMP pathway that is required for epidermal differentiation during Xenopus early embryonic development. We show that Xenopus EIG121L (xEIG121L) protein, an evolutionarily conserved transmembrane protein, is expressed in the ventral ectoderm at the gastrula and neurula stages. Almost complete knockdown of xEIG121L protein with antisense morpholino oligonucleotides in early Xenopus embryos results in severe developmental defects, including the inhibition of epidermal differentiation and the induction of neural genes. Remarkably, our analysis shows that BMP/Smad1 signaling is severely suppressed in the xEIG121L knockdown ectoderm. Moreover, immunoprecipitation and immunostaining experiments suggest that xEIG121L protein physically interacts, and co-localizes, with BMP receptors. Thus, our results identify a novel regulator of the BMP pathway that has a positive role in BMP signaling and plays an essential role in epidermal differentiation during early embryonic development.

Vitamin D regulates steroidogenesis and insulin-like growth factor binding protein-1 (IGFBP-1) production in human ovarian cells

Vitamin D Receptor (VDR) is expressed in both animal and human ovarian tissue, however, the role of vitamin D in human ovarian steroidogenesis is unknown. Cultured human ovarian cells were incubated in tissue culture medium supplemented with appropriate substrates, with or without 50 pM-150 pM or 50 nM-150 nM of 1,25-(OH)2D3, and in the presence or absence of insulin. Progesterone, testosterone, estrone, estradiol, and IGFBP-1 concentrations in conditioned tissue culture medium were measured. Vitamin D receptor was present in human ovarian cells. 1,25-(OH)2D3 stimulated progesterone production by 13% (p<0.001), estradiol production by 9% (p<0.02), and estrone production by 21% (p<0.002). Insulin and 1,25-(OH)2D3 acted synergistically to increase estradiol production by 60% (p<0.005). 1,25-(OH)2D3 alone stimulated IGFBP-1 production by 24% (p<0.001), however, in the presence of insulin, 1,25-(OH)2D3 enhanced insulin-induced inhibition of IGFBP-1 production by 13% (p<0.009). Vitamin D stimulates ovarian steroidogenesis and IGFBP-1 production in human ovarian cells likely acting via vitamin D receptor. Insulin and vitamin D synergistically stimulate estradiol production. Vitamin D also enhances inhibitory effect of insulin on IGFBP-1 production.

Gadolinium enhancement of cauda equina after combined spinal-epidural anaesthesia

The occurrence of neurological symptoms after spinal anaesthesia has been reported with several local anaesthetics including lidocaine, prilocaine, mepivacaine, tetracaine and bupivacaine. Although hyperbaric bupivacaine is known to induce neurological symptoms less frequently than lidocaine, a few cases of cauda equina syndrome (CES) following the intraspinal injection of bupivacaine have been reported in the English literature. We describe lumbar MRI findings for a 29-year-old woman presenting with CES after caesarean section.

Dyke-Davidoff-Masson Syndrome Demonstrated by Current MR Images

Current magnetic resonance imaging techniques demonstrated MR findings of Dyke-Davidoff-Masson syndrome in a 44-year-old man. Statistical parametric mapping analysis of the T1-weighted images showed focal atrophy in the basal ganglia. Three-dimensional white matter fibers of corticospinal tracts, corpus callosum and cingulate bundle were demonstrated using diffusion tensor data correlated to the patient's clinical conditions.

Defect structures in nematic liquid crystals around charged particles

We numerically study the orientation deformations in nematic liquid crystals around charged particles. We set up a Ginzburg-Landau theory with inhomogeneous electric field. If the dielectric anisotropy epsilon 1 is positive, Saturn-ring defects are formed around the particles. For epsilon 1< 0 , novel "ansa" defects appear, which are disclination lines with their ends on the particle surface. We find unique defect structures around two charged particles. To lower the free energy, oppositely charged particle pairs tend to be aligned in the parallel direction for epsilon 1> 0 and in the perpendicular plane for epsilon 1< 0 with respect to the background director. For identically charged pairs the preferred directions for epsilon 1> 0 and epsilon 1< 0 are exchanged. We also examine competition between the charge-induced anchoring and the short-range anchoring. If the short-range anchoring is sufficiently strong, it can be effective in the vicinity of the surface, while the director orientation is governed by the long-range electrostatic interaction far from the surface.