Quantitative Evaluation of Calf Muscle Pump Function after Deep Vein Thrombosis by Non-Invasive Venous Tests

In order to quantitatively evaluate calf muscle pump function following deep vein thrombosis (DVT), expelled volume was investigated by strain gauge plethysmography (SPG). Thirty-six patients with 43 diseased lower limbs and nine healthy persons with 16 control limbs were studied. Of 43 diseased limbs, 20 symptomatic limbs were distinguished from 23 asymptomatic limbs by the presence of heaviness or aching. The following ***noninvasive parameters for the quantitative evaluation of calf muscle pump function, venous refilling time (VRT), venous outflow (VO), venous return (VR), and expelled volume (EV) were measured by SPG or photoplethysmography (DPG). Ambulatory venous pressure (AVP) was taken to represent the standard for calf muscle pump function. Using SPG, the EV, VR, and VRTs distinguished three groups (control, asymptomatic and symptomatic). Among seven indicators (EV, VR, VO, VRTs), EV had the highest correlation coefficient with the AVP ( r = +0.728). A positive EV was present in 85% of the symptomatic limbs, but in only 4% of the asymptomatic limbs. It is concluded that the EV is a useful non-invasive indicator for the quantitative evaluation of calf muscle pump function after deep vein thrombosis.

Patterns of metastasis and recurrence in thymic epithelial tumours: longitudinal imaging review in correlation with histological subtypes

AIM

To determine the patterns of metastasis and recurrence in thymic epithelial tumours based on longitudinal imaging studies, and to correlate the patterns with World Health Organization (WHO) histological classifications.

MATERIALS AND METHODS

Seventy-seven patients with histopathologically confirmed thymomas (n=62) and thymic carcinomas (n=15) who were followed with cross-sectional follow-up imaging after surgery were retrospectively studied. All cross-sectional imaging studies during the disease course were reviewed to identify metastasis or recurrence. The sites of involvement and the time of involvement measured from surgery were recorded.

RESULTS

Metastasis or recurrence was noted in 24 (31%) of the 77 patients. Patients with metastasis or recurrence were significantly younger than those without (median age: 46 versus 60, respectively; p=0.0005), and more commonly had thymic carcinomas than thymomas (p=0.002). The most common site of involvement was the pleura (17/24), followed by the lung (9/24), and thoracic nodes (9/24). Abdominopelvic involvement was noted in 12 patients, most frequently in the liver (n=8). Lung metastasis was more common in thymic carcinomas than thymomas (p=0.0005). Time from surgery to the development of metastasis or recurrence was shortest in thymic carcinoma, followed by high-risk thymomas, and was longest in low-risk thymoma (median time in months: 25.1, 68.8, and not reached, respectively; p=0.0015).

CONCLUSIONS

The patterns of metastasis and recurrence of thymic epithelial tumours differ significantly across histological subgroups, with thymic carcinomas more commonly having metastasis with shorter length of time after surgery. The knowledge of different patterns of tumour spread may contribute to further understanding of the biological and clinical behaviours of these tumours.

Correlative near-infrared light and cathodoluminescence microscopy using Y2O3:Ln, Yb (Ln = Tm, Er) nanophosphors for multiscale, multicolour bioimaging

This paper presents a new correlative bioimaging technique using Y₂O₃:Tm, Yb and Y₂O₃:Er, Yb nanophosphors (NPs) as imaging probes that emit luminescence excited by both near-infrared (NIR) light and an electron beam. Under 980 nm NIR light irradiation, the Y₂O₃:Tm, Yb and Y₂O₃:Er, Yb NPs emitted NIR luminescence (NIRL) around 810 nm and 1530 nm, respectively, and cathodoluminescence at 455 nm and 660 nm under excitation of accelerated electrons, respectively. Multimodalities of the NPs were confirmed in correlative NIRL/CL imaging and their locations were visualized at the same observation area in both NIRL and CL images. Using CL microscopy, the NPs were visualized at the single-particle level and with multicolour. Multiscale NIRL/CL bioimaging was demonstrated through in vivo and in vitro NIRL deep-tissue observations, cellular NIRL imaging, and high-spatial resolution CL imaging of the NPs inside cells. The location of a cell sheet transplanted onto the back muscle fascia of a hairy rat was visualized through NIRL imaging of the Y₂O₃:Er, Yb NPs. Accurate positions of cells through the thickness (1.5 mm) of a tissue phantom were detected by NIRL from the Y₂O₃:Tm, Yb NPs. Further, locations of the two types of NPs inside cells were observed using CL microscopy.

Acid-inhibitory effects of vonoprazan 20 mg compared with esomeprazole 20 mg or rabeprazole 10 mg in healthy adult male subjects--a randomised open-label cross-over study

BACKGROUND

Proton pump inhibitors (PPIs) are widely used for the treatment of acid-related diseases. Vonoprazan is a member of a new class of acid suppressants; potassium-competitive acid blockers. Vonoprazan may thus be an alternative to PPIs.

AIM

To evaluate efficacy, rapidity and duration of acid-inhibitory effects of vonoprazan vs. two control PPIs, esomeprazole and rabeprazole, in 20 healthy Japanese adult male volunteers with CYP2C19 extensive metaboliser genotype.

METHODS

In this randomised, open-label, two-period cross-over study, vonoprazan 20 mg and esomeprazole 20 mg (Study V vs. E) or rabeprazole 10 mg (Study V vs. R) were orally administered daily for 7 days. Primary pharmacodynamic endpoint was gastric pH over 24 h measured as percentage of time pH ≥3, ≥4 and ≥5 (pH holding time ratios; HTRs) and mean gastric pH.

RESULTS

Acid-inhibitory effect (pH4 HTR) of vonoprazan was significantly greater than that of esomeprazole or rabeprazole on both Days 1 and 7; Day 7 difference in pH4 HTR for vonoprazan vs. esomeprazole was 24.6% [95% confidence interval (CI): 16.2-33.1] and for vonoprazan vs. rabeprazole 28.8% [95% CI: 17.2-40.4]. The Day 1 to Day 7 ratio of 24-h pH4 HTRs was >0.8 for vonoprazan, compared with 0.370 for esomeprazole and 0.393 for rabeprazole. Vonoprazan was generally well tolerated. One vonoprazan subject withdrew due to a rash which resolved after discontinuation.

CONCLUSIONS

This study demonstrated a more rapid and sustained acid-inhibitory effect of vonoprazan 20 mg vs. esomeprazole 20 mg or rabeprazole 10 mg. Therefore, vonoprazan may be a potentially new treatment for acid-related diseases.

Automated and accurate carotid bulb detection, its verification and validation in low quality frozen frames and motion video

AIM

Carotid intima-media thickness (cIMT) measurements during clinical trials need to have a fixed reference point (also called as bulb edge points) in the anatomy from which the cIMT can be measured. Identification of the bulb edge points in carotid ultrasound images faces the challenge to be detected automatically due to low image quality and variations in ultrasound images, motion artefacts, image acquisition protocols, position of the patient, and orientation of the linear probe with respect to bulb and ultrasound gain controls during acquisition.

METHODS

This paper presents a patented comprehensive methodology for carotid bulb localization and bulb edge detection as a reference point. The method consists of estimating the lumen-intima borders accurately using classification paradigm. Transition points are located automatically based on curvature characteristics. Further we verify and validate the locations of bulb edge points using combination of several local image processing methods such as (i) lumen-intima shapes, (ii) bulb slopes, (iii) bulb curvature, (iv) mean lumen thickness and its variations, and (v) geometric shape fitting.

RESULTS

Our database consists of 155 ultrasound bulb images taken from various ultrasound machines with varying resolutions and imaging conditions. Further we run our automated system blindly to spot out the bulbs in a mixture database of 336 images consisting of bulbs and no-bulbs. We are able to detect the bulbs in the bulb database with 100% accuracy having 92% as close as to a neurologists's bulb location. Our mean lumen-intima error is 0.0133 mm with precision against the manual tracings to be 98.92%. Our bulb detection system is fast and takes on an average 9 seconds per image for detection for the bulb edge points and 4 seconds for verification/validation of the bulb edge points.

Correlative cathodoluminescence and near-infrared fluorescence imaging for bridging from nanometer to millimeter scale bioimaging

Correlative light and electron microscopy (CLEM) is one attractive method of observing biological specimens because it combines the advantages of both light microscopy (LM) and electron microscopy (EM). In LM, specimens are fully hydrated, and molecular species are distinguished based on the fluorescence colors of probes. EM provides both high-spatial-resolution images superior to those obtained with LM and ultrastructural information of cellular components. The combination of LM and EM gives much more information than either method alone, which helps us to analyze cellular function in more detail.We propose a Y2O3:Tm,Yb phosphor nanoparticle which allows upconversion luminescence (UCL) imaging with near-infrared (NIR) light excitation and cathodoluminescence (CL) imaging [1], where the light emission induced by an electron beam is called cathodoluminescence (CL). Due to electron beam excitation, the spatial resolution of CL microscopy is on the order of nanometers [2,3]. Upconversion is a process in which lower energy, longer wavelength excitation light is transduced to higher energy, shorter wavelength emission light. So far, in LM observation for CLEM, ultraviolet (UV) or visible light has been used for excitation. However, UV and visible light have limited ability to observe deep tissue regions due to absorption, scattering, and autofluorescence. On the other hand, NIR light does not suffer from these problems. Rare-earth-doped upconversion nanophosphors have been applied to biological imaging because of the advantages of NIR excitation [4].We investigated the UCL and CL spectra of Y2O3:Tm,Yb nanophosphors. Y2O3:Tm,Yb nanophosphors that emit visible and near-infrared UCL under 980nm irradiation and blue CL via electron beam excitation. To confirm bimodality of our nanophosphors, correlative UCL/CL images of the nanophosphors were obtained for the same region. The nanophosphors were poured onto a P doped Si substrate (Fig. 1(a)) and were irradiated with 980 nm NIR CW laser light or an electron beam. Fig. 1(b) shows the UCL image of the nanophosphors under 980 nm NIR CW laser irradiation, UCL spots were observed, but the individual nanophosphors in each spot were difficult to distinguish in the UCL image. On the other hand, the edges and the gap between the nanophosphors were clearly distinguished in the CL image (Fig. 1(c)), showing that the spatial-resolution of CL imaging was enough higher than that of UCL image. We believe that upconversion phosphors of the type described here will allow the realization of new CLEM imaging techniques covering the nanometer to millimeter scale, i.e., the molecular to in vivo scale.jmicro;63/suppl_1/i29/DFU073F1F1DFU073F1Fig. 1.(a) SEM and correlative (b) UCL (intensity of 980 nm NIR CW laser 8 mW) and (c) CL images of Y2O3:Tm,Yb nanophosphors in same region (accelerating voltage 3 kV, exposure time 100 ms/pixel).

Link between automated coronary calcium volumes from intravascular ultrasound to automated carotid IMT from B-mode ultrasound in coronary artery disease population

AIM

Establishing relationship between coronary calcium volumes from Intravascular Ultrasound (IVUS) and automated carotid intima-media thickness (cIMT) helps in understanding the genetic nature of atherosclerosis disease. In this research, we have quantified the detected calcium from IVUS video frames and associated a relationship between coronary calcium volumes computed and automated cIMT from B-mode ultrasound.

METHODS

Coronary calcium volume is computed from IVUS and auto cIMTs are computed using B-mode ultrasound. An automated computer based application is developed and tested on 100 patient volumes (an average of 2549 frames per volume) to calculate lesion area and normalized coronary calcium volume. We use an integrated approach for volume computation which is based on lesion area per frame. We have measured the normalized volume from the calcium detected video frames using proposed integration method. The cIMT of 100 carotids were measured with novel and dedicated automated software analysis (AtheroEdge™ from AtheroPoint™ LLC, Roseville, CA, USA).

RESULTS

The computer-based coronary calcium volume (from IVUS) showed a correlation coefficient with respect to cIMT for left and right carotids as 9.1% and 13.9%, respectively.

CONCLUSION

Coronary calcium volume computed from IVUS and auto cIMT are moderately correlated. The association between auto cIMT (right side) vs. computer-based coronary calcium volume (IVUS) is stronger than the association between auto cIMT (left side) vs. computer-based coronary calcium volume.

Tropomyosin-related receptor kinase B at the invasive front and tumour cell dedifferentiation in gastric cancer

Background:

Tropomyosin-related receptor kinase B (TrkB) promotes proliferation and invasion, relating to poor prognosis of various malignancies. We examined the role of TrkB at the invasive front of gastric cancer (GC) and its association with tumour cell dedifferentiation and tumour budding.

Methods:

Immunoreactive TrkB was evaluated at the tumour centre and margin using whole-tissue sections of 320 GC patients. Tumour cell dedifferentiation was defined as higher histologic grade at the tumour margin than the surface or tumour centre. Tumour budding was also scored on cytokeratin-stained sections.

Results:

Sixty-five patients (20%) showed higher TrkB expression at the invasive front (TrkB expression was higher at the tumour margin than tumour centre). It was significantly associated with several aggressive phenotypes in the full cohort (n=320). It showed a prognostic significance in test subgroup (n=98) and was identified as an independent prognostic factor (HR=2.09; 95% CI: 1.26–3.53) by multivariate analysis in validation subgroup (n=222). Twenty-one patients showed tumour cell dedifferentiation. In predominantly differentiated tumour, higher TrkB at the invasive front was significantly associated with tumour budding rather than tumour cell dedifferentiation.

Conclusions:

Assessment of immunoreactive TrkB at the invasive front by whole-tissue sections provides prognostic information for GC patients.

Intrathymic cyst: clinical and radiological features in surgically resected cases

AIM

To investigate radiological and clinical characteristics of pathologically proven cases of intrathymic cysts.

MATERIALS AND METHODS

The study population consisted of 18 patients (five males, 13 females; median age 56 years) with pathologically confirmed intrathymic cysts who underwent thymectomy and had preoperative chest computed tomography (CT) available for review. The patient demographics, clinical presentation, and preoperative radiological diagnoses were reviewed. CT images were evaluated for shape, contour, location of the cysts and the presence of adjacent thymic tissue, mass effect, calcifications, and septa. The size and CT attenuations of the cysts were measured.

RESULTS

The most common CT features of intrathymic cysts included oval shape (9/18; 50%), smooth contour (12/18; 67%), midline location (11/18; 61%), the absence of visible adjacent thymic tissue (12/18; 67%), and the absence of calcification (16/18; 89%). The mean longest diameter and the longest perpendicular diameter were 25 mm (range 17-49 mm) and 19 mm (range 10-44 mm), respectively. The mean CT attenuation was 38 HU (range 6-62 HU) on contrast-enhanced CT, and was 45 HU (range 26-64 HU) on unenhanced CT (p = 0.41). The CT attenuation was >20 HU in 15 of 18 patients (83%). Preoperative radiological diagnosis included thymoma in 11 patients.

CONCLUSION

In surgically removed, pathologically proven cases of intrathymic cyst, the CT attenuation was >20 HU in most cases, leading to the preoperative diagnosis of thymoma. Awareness of the spectrum of imaging findings of the entity is essential to improve the diagnostic accuracy and patient management.

Comparison of 7 α(1)-adrenoceptor antagonists in patients with lower urinary tract symptoms associated with benign prostatic hyperplasia:a short-term crossover study

A crossover study was conducted to identify the best α1-adrenoceptor (α1AR) antagonist for individual patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). One hundred thirteen patients (mean age 70.8 years) were enrolled. All patients met BPH clinical study guidelines. Seven agents were utilized:tamsulosin 0.2mg, silodosin 8mg, urapidil 60mg, naftopidil 50mg, prazosin 1mg, terazosin 2mg, and doxazosin 1mg. Patients were initially prescribed tamsulosin or silodosin for a week and then urapidil for a week. Two weeks later, they were prescribed the better of the 2 agents for a week and a new agent for the next week. This cycle was repeated until all 7 agents were tested. Efficacy was evaluated with the International Prostate Symptom Score. The agent rankings were doxazosin (25 [22%]), silodosin (22 [19%]), urapidil (19 [17%]), naftopidil (17 [15%]), terazosin (12 [11%]), tamsulosin (11 [10%]), prazosin (7 [6%]). Only 12 patients (11%) changed agents after the crossover study was completed. The major reason was adverse events (83%). We found that each of the 7 α1AR antagonists has its own supporters. Further, the one-week crossover study was useful in identifying the best agent for the treatment of each individual with LUTS.

Protective effect of pitavastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, on ischemia-induced neuronal damage

We investigated the neuroprotective effects of a novel 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor (pitavastatin) on ischemic neuronal damage in gerbils using immunohistochemistry. The animals were allowed to survive for 14 days after 5 min of ischemia induced by bilateral occlusion of the common carotid arteries. Five days after ischemia, severe neuronal cell loss was observed in the hippocampal CA1 sector. Prophylactic treatment with pitavastatin dose-dependently prevented the hippocampal CA1 neuronal cell loss 5 days after ischemia. Immunohistochemical study did not show the change of nNOS and iNOS expression in the hippocampus except for, in a few regions, up to 1 day after ischemia. Thereafter, the expression of iNOS was observed in the hippocampal CA1 sector 5 and 14 days after ischemia. In contrast, the expression of nNOS and eNOS gradually decreased in the hippocampal CA1 sector up to 14 days after ischemia. Prophylactic treatment with pitavastatin also prevented the expression of iNOS and the decrease of eNOS expression and the number of nNOS-positive cells in the hippocampal CA1 sector 5 days after ischemia. However, prophylactic treatment with pitavastatin at a dose of 10 mg kg(-1) did not change the immunoreactivity of iNOS and nNOS in the hippocampus at an early phase after ischemia. In contrast, this drug prevented the reduction of eNOS immunoreactivity in the hippocampal CA1 neurons at an early phase after ischemia. These findings demonstrate that the HMG-CoA reductase inhibitor pitavastatin can protect hippocampal CA1 neurons after transient forebrain ischemia through up-regulation of eNOS expression in this region. Thus pharmacological modulation of eNOS expression may offer a novel therapeutic strategy for cerebral ischemic stroke.

Orbital masses: the usefulness of diffusion-weighted imaging in lesion categorization

INTRODUCTION

Diffusion-weighted imaging (DWI) produces contrast among different kinds of tissues according to their diffusibility characteristics. The purpose of our study was to evaluate the role of DWI including measurement of apparent diffusion coefficient (ADC) values in recognizing benignancy or malignancy of orbital masses.

METHODS

A total of 39 orbital masses were evaluated visually for signal characteristics on DWI and ADC maps. ADC values were calculated for each lesion. Visual signal characteristics were compared using the Fisher exact test. Receiver operating characteristic (ROC) analysis was carried out to determine sensitivity and specificity for distinguishing malignant from benign lesions using ADC values. The Mann-Whitney U test was applied to compare the ADC values between orbital lymphomas and idiopathic orbital inflammatory (IOI) lesions, and between optic nerve sheath meningiomas and gliomas.

RESULTS

Visual assessment revealed no significant difference between benign and malignant lesions on DWI (p-value = 0.66). However, visual assessment of ADC maps revealed a statistically significant (p-value ≤ 0.0001) between benign and malignant lesions. ROC analysis showed a sensitivity of 83.33 % and a specificity of 85.71 % when using an optimal cut off ADC value of 0.84 × 10(-3) mm(2)/s for differentiating malignant from benign lesions. Significant differences in mean ADC values were observed between lymphomas and IOI lesions (p-value = 0.05), and between optic nerve sheath meningiomas and gliomas (p-value = 0.03).

CONCLUSION

DWI is useful for differentiating malignant and benign orbital tumors if accompanied by visual assessment of ADC maps and ADC value calculations.