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Pharyngeal collapse has been described as a decrease of more than 50% in the diameter of the lumen. However, there has been no study on changes in the pharyngeal lumen in clinically normal dogs. The hypothesis of this prospective, observational, and pilot study was that change in nasopharyngeal lumen would be over 50% in Beagle dogs without cardiopulmonary diseases. Thus, we assessed the nasopharyngeal luminal change using cervical radiography in Beagle dogs without respiratory signs or cardiac abnormalities. The study sample included 42 Beagle dogs without cardiopulmonary diseases. Cervical radiographies were acquired during inspiration and expiration, and nasopharyngeal luminal change (%) was calculated. The median nasopharyngeal luminal change was 16.6%, and nasopharyngeal luminal change over 50% was identified in two dogs. The nasopharyngeal luminal change was significantly associated with body condition score and body weight. There was no correlation between nasopharyngeal luminal change and age. This study revealed that change in nasopharyngeal lumen over 50% can be identified in Beagle dogs without cardiopulmonary diseases and may be over-diagnosed as partial pharyngeal collapse. Further studies for comparing change in nasopharyngeal lumen between clinically normal dogs and dogs with respiratory signs are warranted.

BACKGROUND Atrial tachyarrhythmias (ATAs) are common within the 3-month blanking period after catheter ablation of atrial fibrillation (AF). However, little evidence is available regarding the current guidelines on the blanking period after surgical AF ablation. We investigate the incidence and significance of early recurrence of atrial tachyarrhythmia (ERAT) and evaluate the optimal blanking period after surgical AF ablation. METHODS Data from 259 patients who underwent surgical AF ablation from 2009 to 2016 were collected. ERAT was defined as documented ATA episodes lasting for 30 s. A multivariate Cox proportional hazard model was constructed to evaluate the role of ERAT as a predictor of late recurrences (LR) for AF. RESULTS In total, 127 patients (49.0%) experienced their last episodes of ERAT during the first (n = 65), second (n = 14), or third (n = 48) month of the 3-month blanking period (p

Radiography is a standard diagnostic test for characterizing left heart enlargement in dogs however limited information is available on the effects of respiratory phases. This prospective and retrospective method comparison study investigated the respiratory effect on the size and shape of the left heart in dogs to determine the usefulness of expiratory radiographs to detect enlargements in the left atrium (LA) and left ventricle (LV). Thoracic radiographs taken at full inspiration and expiration were evaluated in 20 normal beagles and 100 dogs diagnosed with mitral regurgitation (MR). Vertebral heart score (VHS), vertebral left atrial size, elevation of the carina, and dorsal bulging of LA on lateral view and lateral bulging of the left auricular appendage and LV on ventrodorsal view were assessed. In normal dogs, there were no significant differences in the evaluative factors between inspiration and expiration. In dogs with MR, VHS did not change according to respiration. However, bulging of the LA, left auricular appendage, and LV had sharp margin during expiration compared with inspiration. The expiratory radiographic finding of LA bulging had a higher correlation with the LA to aorta ratio compared with LA bulging in the inspiratory radiography. Using a LA to aorta echocardiographic ratio greater than 1.5 as the gold standard, the radiographic sensitivity for LA enlargement was higher during expiration than inspiration. These findings of our study indicated that expiratory radiography can be helpful to support the detection of left heart enlargement, although it can overestimate LA enlargement in dogs with MR.

Rapid contrast injection is recommended for triple-phase helical computed tomography (CT) of the liver. However, a large-gauge catheter is needed for faster contrast injection and this is not practical for small breed dogs or cats. The purpose of this crossover group study was to evaluate applicability of a lower injection rate with a small-gauge (G) catheter for triple-phase hepatic CT in small dogs. Triple-phase CT images were acquired for six beagle dogs using three protocols: an injection rate of 1.5 ml/s with a 24 G catheter, 3.0 ml/s with a 22 G catheter, and 4.5 ml/s with a 20 G catheter. Enhancement of the aorta, portal vein, and hepatic parenchyma was measured in each phase (arterial, portal, and delayed) and image quality was scored subjectively by two observers. Injection duration, time to scan delay, and time to peak enhancement were also recorded. Contrast injection duration decreased with a higher injection rate (n = 6, P ≤ 0.01), but time to peak enhancement and time to scan delay were not significantly affected by injection rates and catheter sizes. Contrast injection rate did not significantly affect aortic, portal, and hepatic enhancement. In addition, separation between each phase and quality of images was subjectively scored as good regardless of injection rate. Findings from the current study supported using an injection rate of 1.5 ml/s with a catheter size of 24 G for triple-phase hepatic CT in small dogs (weight < 12 kg).

A quasi-classical trajectory approach is used to study vibrational relaxation and CH bond dissociation in toluene–halogen molecule collisions at 300 K. The overall interaction energy includes Morse-type intramolecular terms of toluene and halogen, and Morse-type intermolecular terms between toluene and halogen. All important bond stretching, bending, and intramolecular coupling terms in toluene are considered in solving the equations of motion. The main vibrational relaxation pathway by the highly excited toluene is from vibration to translation. The intermolecular vibration-to-vibration pathway is negligible. As the mass increases from F2 to I2 , the energy loss by toluene decreases, whereas the extent of CH bond dissociation increases as a larger amount of vibrational energy remains in toluene for intramolecular flow to the bond. The dissociation probability of methyl CH bond is significantly higher than that of ring CH bond as the low-frequency CCCH3 bending vibration plays the role of an efficient conduit of energy flow.

Thyroid disease is common in dogs and conventional ultrasonography is a standard diagnostic test for diagnosis and treatment planning. Strain elastography can provide additional information about tissue stiffness noninvasively after applying external or internal compression. However, natural carotid artery pulsations in the canine thyroid gland are too weak to maintain sufficient internal compression force. The objective of the present study was to describe the feasibility of strain elastography for evaluating the canine thyroid gland and the repeatability of dobutamine-induced carotid artery pulsation as an internal compression method. In seven healthy Beagle dogs, strain on each thyroid lobe was induced by external compression using the ultrasound probe and internal compression using carotid artery pulsation after dobutamine infusion. The thyroid appeared homogeneously green and the subcutaneous fat superficial to the thyroid lobe appeared blue. Strain values and strain ratios did not differ among dogs or between the left and right lobes. Interobserver repeatability was excellent for both compression methods. Intraobserver repeatability of the strain ratio measured using the carotid artery pulsation method (intraclass coefficient correlation = 0.933) was higher than that measured using the external compression method (0.760). Mean strain values of thyroid lobes for the external compression method (142.93 ± 6.67) differed from the internal method (147.31 ± 8.24; P < 0.05). Strain ratios between the two methods did not differ. Strain elastography was feasible for estimating thyroid stiffness in dogs. Carotid artery pulsation induced by dobutamine infusion can be used for canine thyroid strain elastography with excellent repeatability.

Standard ultrasonography is often insensitive for distinguishing normal vs. diseased states for canine abdominal organs. Ultrasonographic elastography is a new technique that is becoming increasingly available and may help to improve sensitivity. This study evaluated the feasibility, repeatability, and reproducibility of strain elastography of the liver, spleen, kidneys, and prostate in healthy dogs and described the elasticity of each organ using strain values and strain ratios. The reproducibility of strain elastography was excellent, and intraobserver repeatability was moderate to excellent. The strain value of each organ was not significantly different among dogs (liver = 143.38 ± 7.41, spleen = 141.04 ± 9.03, left renal cortex = 141.26 ± 7.50, right renal cortex = 145.80 ± 7.79, and prostate = 135.46 ± 5.80), except for the renal medulla (left = 51.19 ± 4.54 and right = 51.93 ± 5.09) (P < 0.05). The strain ratios for the liver, spleen, renal cortex, and prostate were similar with no significant difference (liver = 10.20 ± 1.47, spleen = 8.40 ± 1.53, left renal cortex = 9.62 ± 1.56, right renal cortex = 8.29 ± 1.63, and prostate = 8.20 ± 1.21), except for the renal medulla (left = 3.48 ± 0.68 and right = 2.95 ± 0.63) (P < 0.05). Our results indicated that strain elastography was feasible for estimating tissue stiffness in the canine liver, spleen, kidneys, and prostate. This study provides basic information for strain values and strain ratios for the liver, spleen, kidneys, and prostate in clinically normal dogs.

In this paper, we present piezoelectric energy harvesters with pillar- and bulk-type multilayer ceramic–polymer composite structures as energy sources. The 0.2(PbMg1/3Nb2/3O3)–0.8(PbZr0.475Ti0.525O3) ceramics were sintered and poled using the conventional ceramic process. The piezoelectric ceramics were prepared in the form of rectangular pillar- and cylindrical bulk-type structures and were attached to the metallic bottom electrode with poled states. Symmetric upper electrodes were attached to the other side. The pillar- and bulk-type ceramic structures were filled with polydimethylsiloxane (PDMS). Subsequently, the two ceramic structure types were manufactured with single-, double-, and triple-layer devices. Both the multi- and single-layer devices were compared using several analysis methods. The piezoelectric properties, including the piezoelectric constant, are discussed in this paper. We also studied the output power of the multi- and single-layer devices.

We report the sonographic pathologic correlation in a case of Hurthle cell thyroid adenoma with an eggshell calcification in a 58-year-old woman. The mass was hypoechoic with a continuous eggshell calcification on gray-scale sonographic and intranodular vascularity power Doppler imaging. At pathological examination, the dystrophic calcification of eggshell type was located between the intact fibrous capsule and the main tumor matrix. Hurthle cell adenoma should be included in the differential diagnosis of a thyroid nodule with an eggshell calcification. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42:172–175, 2014

We report the imaging and pathologic findings of a case of myopericytoma of the neck in a 70-year-old woman, which was diagnosed by ultrasound-guided core-needle biopsy. The mass demonstrated homogeneous intense enhancement on contrast-enhanced CT and was markedly hypervascular on power Doppler sonography. The histopathological findings of the core biopsy were consistent with myopericytoma.

A 71-year-old man presented with mucosa-associated lymphoid tissue (MALT) lymphoma of the submandibular gland 52 months after initial diagnosis of MALT lymphoma of the lung. Ultrasonography showed a well-demarcated, markedly hypoechoic, heterogeneous solid mass with linear echogenic strands and hypervascularity. Ultrasound-guided core-needle biopsy demonstrated histological findings of MALT lymphoma. Sonographic features of MALT lymphoma of the submandibular gland are characteristic and ultrasound-guided core-needle biopsy may be a suitable replacement for surgical biopsy.

With the introduction of high-resolution sonographic equipment and fineW needle aspiration biopsy (FNAB), many thyroid cancers that are too small to be palpated are being diagnosed. Most papillary thyroid carcinoma (PTC) is hypoechoic on gray scale sonography. Postpartum thyroiditis is an autoimmune disorder of the thyroid gland, which occurs in the first year after parturition. Hypoechogenicity of the thyroid gland is the main sonographic feature of postpartum thyroiditis. 1 Thus, hypoechoic PTC may be masked by hypoechoic background thyroid parenchyma of postpartum thyroiditis and may be unnoticed on sonography. Here we report a case of biopsy-proven PTC that was not visualized temporarily on sonography during the active phase of postpartum thyroiditis and was again visualized after improvement of active thyroiditis, along with gray scale and power Doppler sonographic findings.

Diallyl disulfide (DADS) is the most prevalent oil-soluble sulfur compound in garlic and inhibits cell proliferation in many cancer cell lines. Here we examined DADS cytotoxicity in a redox-mediated process, involving reactive oxygen species (ROS) production. In the present study, p53-independent cell cycle arrest at G2/M phase was observed with DADS treatment, along with time-dependent increase of cyclin B1. In addition, apoptosis was also observed upon 24-h DADS treatment accompanied by activation of p53. In HCT-116 cells, DADS application induced a dose-dependent increase and time-dependent changes in ROS production. Scavenging of DADS-induced ROS by N-acetyl cysteine or reduced glutathione inhibited cell cycle arrest, apoptosis and p53 activation by DADS. These results suggest that ROS trigger the DADS-induced cell cycle arrest and apoptosis and that ROS are involved in stress-induced signaling upstream of p53 activation. Transfection of p53 small interfering RNA prevents the accumulation of cleaved poly(ADP-ribose) polymerase and sub-G1 cell population by 65% and 35%, respectively. Moreover, DADS-induced apoptosis was also prevented by treatment with oligomycin, which is known to prevent p53-dependent apoptosis by reducing ROS levels in mitochondria. These results suggest that mitochondrial ROS may serve as second messengers in DADS-induced apoptosis, which requires activation of p53.

This article is concerned with the fundamental and experimental overview of the rotating disc electrode (RDE) and rotating ring–disc electrode (RRDE) techniques. First, this review provides a brief discourse on the basic concepts and general descriptions of the RDE and RRDE techniques. Then, the theoretical derivation of the governing equations for the RDE and RRDE is described with the definition of the important kinetic parameters. Finally, the experimental applications of RDE and RRDE techniques to investigate the mechanism and kinetics of oxygen reduction at Pt-dispersed carbon (Pt/C) electrodes for fuel cells are discussed in detail from a practical point of view.

Redox-sensitive transcriptional regulator redox factor-1 (Ref-1) is induced by oxidative stress and protects cells against it. However, the function of Ref-1 in regulating nitric oxide (NO) synthesis in macrophages has not been defined. We investigated the role of Ref-1 related to the regulation of NO synthesis in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. LPS stimulates the up-regulation and nuclear translocation of Ref-1 in macrophages. Importantly, Ref-1-deficient macrophages using a small interfering RNA did not stimulate inducible NO synthase (iNOS) expression as well as nuclear factor-kappaB nuclear translocation by stimulation with LPS. When the cells were pretreated with diphenyleneiodonium or p47(phox) small interfering RNA for inhibition of NADPH oxidase activity, LPS did not stimulate the nuclear translocation of Ref-1. We next asked whether reactive oxygen species are sufficient for the nuclear translocation of Ref-1 in macrophages. The direct use of H2O2 stimulated the translocation to the nucleus of nuclear factor-kappaB, but not Ref-1 and antioxidant N-acetyl cysteine did not inhibit the LPS-stimulated nuclear translocation of Ref-1. These data suggest that Ref-1 nuclear translocation in LPS-stimulated macrophages requires the activation of other signalling molecules aside from reactive oxygen species followed by the activation of NADPH oxidase.

Purpose To evaluate the effect of incidental magnetization transfer (iMT) in multislice brain imaging at 3.0T. Materials and Methods The contribution of iMT to multislice brain MRI was evaluated at 3.0T. In 10 normal subjects we obtained multislice fast spin-echo (FSE) MR images using a 16-echo pulse train without an off-resonance MT pulse at 3.0T and 1.5T. We quantified the extent of iMT by calculating the iMT ratio (iMTR). Results We found that the iMT contrast (iMTC) has a greater effect at 3.0T. As the number of slices increased in multislice FSE imaging, the difference between two field strengths became larger. Compared to WM structures, however, the difference in iMT effect between 1.5T and 3.0T was smaller in the case of GM structures. Conclusion The iMTC has a greater effect at 3.0T. The strength of the iMT is different for different tissue types and also varies according to the number of slices used. J. Magn. Reson. Imaging 2007. © 2007 Wiley-Liss, Inc.

Purpose To evaluate the feasibility of magnetic resonance voiding cystography (MRVC) compared with voiding cystourethrography (VCUG) for detecting and grading vesicoureteral reflux (VUR). Materials and Methods MRVC was performed upon 20 children referred for investigation of reflux. Either coronal T1-weighted spin-echo (SE) or gradient-echo (GE) (fast multiplanar spoiled gradient-echo (FMPSPGR) or turbo fast low-angle-shot (FLASH)) images were obtained before and after transurethral administration of gadolinium solution, and immediately after voiding. The findings of MRVC were compared with those of VCUG and technetium-99m (99mTc) dimercaptosuccinic acid (DMSA) single-photon emission computed tomography (SPECT) performed within 6 months of MRVC. Results VUR was detected in 23 ureterorenal units (16 VURs by both methods, 5 VURs by VCUG, and 2 VURs by MRVC). With VCUG as the standard of reference, the sensitivity of MRVC was 76.2%; the specificity, 90.0%; the positive predictive value, 88.9%; and the negative predictive value, 78.3%. There was concordance between two methods regarding the grade of reflux in all 16 ureterorenal units with VUR detected by both methods. Of 40 kidneys, MRVC detected findings of renal damage or reflux nephropathy in 13 kidneys, and 99mTc DMSA renal SPECT detected findings of reflux nephropathy in 17 kidneys. Conclusion Although MRVC is shown to have less sensitivity for VUR than VCUG, MRVC may represent a method of choice offering a safer nonradiation test that can additionally evaluate the kidneys for changes related to reflux nephropathy. J. Magn. Reson. Imaging 2005;21:406–414. © 2005 Wiley-Liss, Inc.

We have studied structural and electrical properties of one dimensionally grown single crystalline gallium nitride (GaN) nanowires (NWs) for nanoscale devices using a metal-initiated metal-organic chemical vapor deposition (MOCVD). GaN nanowires were formed via the vapor-liquid-solid (VLS) mechanism with gold, iron, or nickel as growth initiators and were found to have triangular cross-sections with widths of 15 ∼ 200 nm and lengths of 5 ∼ 20 μm. TEM confirmed that the nanowires were single crystalline and were well oriented along the [210] or [110] direction on substrate depending on the metal initiators. For electrical transport properties of un-doped GaN nanowires, the back-gated field effect transistors (FET) were also fabricated by standard e-beam lithography. In our electrical measurement, the carrier concentration and mobility were 2 ∼ 4 × 10 18 cm -3 and 60 ∼ 70 cm2/V s, respectively.

InGaN/GaN quantum well light emitting diodes (LEDs) were grown with p-GaN layers of varied Mg impurity content. As the concentration of Mg impurity increases, the hole concentration increases up to a critical Mg impurity density and then decreases with further increase of the impurity. In this work, it is proposed that the accepters form the impurity band and that the band behavior with Mg content variation is attributed to the properties of the p-GaN layer and the p-layer effect on the I-V characteristics of LED.

Complexes of lanthanide with Mordant Red 19 (MR19) are shown to be adsorbed and can be electrochemically reduced at mercury electrodes at a more negative potential than where MR19 is reduced. Based on these properties, an analytical application for the determination of lanthanides is demonstrated by linear sweep voltammetry (LSV) and by highly sensitive adsorptive stripping voltammetry (AdSV). By applying AdSV, the detection limit of several lanthanides is about 5.0 × 10−10 M with an accumulation time of 5 min and the linear response range is from 5.0 × 10−8 M to 1.0 × 10−6 M. A typical relative standard deviation is found to be 5.2% at the 5.0 × 10−8 M level. The results from LSV show that the difference in peak potentials (δEp) between complex and MR19 increases when the atomic number of lanthanide ion is increased. Because the smallest δEp due to the presence of La3+ is still large enough to distinguish the complex peak from dye peak, it is possible to recognize all members of lanthanide ions selectively with MR19, regardless of whether they are light or heavy ones. It is also possible to perform simultaneous analysis for some mixtures. In addition, the range of lanthanide concentration, for which quantitative analysis is valid, becomes wider as a result of using LSV as well as AdSV.

Although hemolytic anemia after mitral valve replacement (MVR) is well recognized, hemolytic anemia associated with mitral valve repair is an uncommon condition. Furthermore, persistent and severe hemolytic anemia despite of medical treatment subsequently requiring reoperation is extremely rare. We here report three cases of intractable hemolytic anemia after mitral valve repair leading to MVR. Collision of regurgitant jet into the annuloplasty ring was the speculated mechanism of hemolysis in all cases. After MVR, all of them experienced immediate resolution of the hemolytic anemia.

The title compound is prepared by evaporation of a stoichiometric solution of Ca(NO3)2, Cu(NO3)2, Fe(NO3)3, TiO2, and citric acid at 70—80 °C, followed by calcination of the obtained gel in air (800 and 900 °C, 6 h each).

Background. To describe gray-scale and power Doppler (PD) sonographic (US) findings of Hurthle cell neoplasms (HCNs) of the thyroid gland, and to determine if there is any correlation between US and gross pathologic features. Method. This retrospective study included 30 pathologically proven HCNs in 30 subjects who underwent preoperative gray-scale and PD US examinations. The size, shape, margin, echogenicity, echotexture, presence or absence of cystic change, calcifications and halo sign, and vascularity at PD US were evaluated. Result. The longest diameter of HCNs ranged from 12 mm to 63 mm. The shape and margins of the mass were ovoid and smooth, respectively, in all cases. The echogenicity was hypoechoic, isoechoic, hyperechoic, or mixed in 43.3%, 33.3%, 10.0%, and 13.3%, respectively. The echotexture was heterogeneous in 73.3% and homogeneous in 26.7%. Cystic change was present in 56.7% and involved less than 25% of the volume of the mass in 50.0% and 26–50% of the volume in 6.7%. Coarse calcifications were present in 20.0%. Halo sign was present in all cases. The vascularity was combined peri- and intranodular in all cases: predominantly intranodular in 50.0%, predominantly perinodular in 46.7%, and of the “inferno” type in 3.3%. All HCNs were encapsulated on gross pathologic examination. Conclusion. Although many of the US features we observed were nonspecific, HCNs tend to have a halo sign and combined peri- and intranodular vascularity on US, which raises the possibility of an association. The US halo sign corresponds to tumor capsule ongross pathologic examination. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 2010

We report herein a case of follicular thyroid adenoma with an eggshell calcification presenting as an intensely hypermetabolic lesion on combined 18F-fluorodeoxyglucose whole-body PET and CT (18F-FDG PET/CT) performed for staging work-up in a 68-year-old woman who had undergone distal gastrectomy with Billroth II anastomosis for early gastric carcinoma. The mass was intensely hypermetabolic (SUVmax = 21.3 g/mL) on combined 18F-FDG PET/CT, hypoechoic with an interrupted eggshell calcification on gray-scale ultrasonography (US), and showed intranodular vascularity on power Doppler US. Follicular adenoma should be considered in the differential diagnosis of a mass with an eggshell calcification on US and intense hypermetabolism on 18F-FDG PET/CT. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010

The authors add a missing reference to the article published in phys. stat. sol. (b) 241, 2775 (2004), referring to one of their own earlier papers in Nano Lett. 3, 1063 (2003). (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)