New protocol for contrast media reduction in atrial fibrillation ablation-planning CT with dual region of interest.

INTRODUCTION: Many patients with atrial fibrillation have impaired renal function, and therefore pre-operative CT for radiofrequency catheter ablation should minimize the use of contrast media. This study describes a dual-region-of-interest (D-ROI) protocol for the scanning of pulmonary veins and left atrium (PVs-LA) with less contrast media and optimized scan timing compared to the single-region-of-interest (S-ROI) protocol, without compromising image quality. METHODS: This study retrospectively included 100 patients who underwent PVs-LA CT between July 2019 and February 2022. The participants were divided into two groups: Those scanned using the S-ROI method (Group A, n = 50), and those scanned using the D-ROI method (Group B, n = 50). Descriptive statistical analysis of the contrast effect and scan timing was performed using quantitative and qualitative data collected from both groups of images. RESULTS: The contrast media dose was larger in group A than in group B (63.6 ± 10.1 mL vs. 45.6 ± 6.9 mL; p < 0.001). The CT values of the PVs-LA did not differ significantly between groups A and B [434.2 ± 77.0 Hounsfield units (HU) and 428.8 ± 77.2 HU, respectively; p = 0.73]. Two evaluators determined appropriate scan timing (when PVs-LA reached a relatively sufficient contrast effect for diagnosis) in 23 (46%) and 45 (90%) patients from groups A and B, respectively (p < 0.001). CONCLUSIONS: Although the radiation dose is slightly increased compared with the S-ROI method, the D-ROI method provides improved scan timing and images with similar contrast enhancement while reducing the amount of contrast medium administered. IMPLICATIONS FOR PRACTICE: The novel D-ROI bolus tracking technique can reduce the contrast medium dose while optimizing scan timing.

Evaluation of pharyngeal swallowing pressure using high-resolution manometry during transoral surgery for oropharyngeal cancer.

BACKGROUND: Transoral robotic surgery is frequently described, driven by the desire to offer a less morbid alternative to chemoradiation. However, the objective evaluation of post-operative function has rarely been reported. Therefore, high-resolution manometry was used in this study to evaluate the impact of changes in peri-operative swallowing function on pharyngeal pressure events. METHODS: Ten patients with various stages of oropharyngeal cancer underwent transoral surgery. High-resolution manometry and videofluoroscopic swallow studies were performed before surgery and two months afterwards. The following parameters were obtained: velopharyngeal and mesopharyngeal post-deglutitive upper oesophageal sphincter pressures, velo-meso-hypopharyngeal contractile integral, upper oesophageal sphincter relaxation pressure, and pharyngeal velocity. RESULTS: There was no significant difference in pharyngeal pressure or contractile integral pre- versus post-operatively. However, pharyngeal velocity was significantly higher post-operatively than pre-operatively. CONCLUSION: High-resolution manometry showed that transoral surgery in patients without pre-operative dysphagia preserved pharyngeal constriction. However, transoral surgery might produce scar formation in the pharynx, which could lead to narrowing of the pharynx.

Efficacy of fluoroscopy-guided endoscopic cricopharyngeal myotomy.

BACKGROUND: In endoscopic cricopharyngeal myotomy, surgeons sometimes have concerns about performing an adequate incision with only a narrow intra-cavital view from one direction. In order to overcome these issues, fluoroscopic radiography was used during endoscopic cricopharyngeal myotomy. METHODS: Peri-operative fluoroscopic radiography was utilised to check the position of the diverticuloscope, and to confirm the extent of the incision during surgery. A balloon catheter was used to determine whether the cricopharyngeal muscle was sufficiently resected. Blood loss, peri-operative complications, and functional oral swallowing scale and penetration aspiration scale scores were evaluated. RESULTS: In 12 out of 15 patients, intra-operative fluoroscopic radiography showed the diverticuloscope positioned in the post-cricoid area, and the cricopharyngeal muscle was raised and the surgery completed without adverse effect. Swallowing functions improved following surgery. CONCLUSION: Intra-operative fluoroscopy might improve endoscopic cricopharyngeal myotomy by allowing surgeons to confirm the extent of resection, and by reducing peri-operative morbidity and complication rates.

A randomized clinical study on postoperative pain comparing between the supraglottic airway device and endotracheal tubing in transabdominal preperitoneal repair (TAPP).

BACKGROUND: Transabdominal preperitoneal (TAPP) repair is the most widely used laparoscopic technique for the treatment of inguinal hernia in Japan. Many studies have shown that in comparison with open hernia repair, laparoscopic repair results in less pain and a shorter convalescence. However, postoperative pain remains a concern. One possible cause of postoperative pain in the early postoperative phase is strain or cough on removal of the endotracheal tube. Use of a supraglottic airway (SGA) device helps to avoid such complaints. We evaluated postoperative pain after TAPP repair using the SGA for general anesthesia. METHODS: We evaluated the postoperative pain in 146 patients with inguinal hernia repaired by TAPP in our hospital between May 2013 and May 2016. A total of 144 adult patients of American Society of Anesthesiologists physical status I and II who underwent needlescopic TAPP surgery were randomly allocated to one of two groups of 72 patients: group A (SGA), in which the patient's airway was secured with an appropriately sized I-gel, and group B (endotracheal tube), in which the airway was secured under laryngoscopy. RESULTS: There was no significant difference between the groups regarding patient background, postoperative hospital stay, and operation time, and TAPP was performed safely in all cases. In the analysis of postoperative pain, the mean Numerical Rating Scale score of peak pain in group A was significantly less than that of group B (2.10 ± 2.05 vs 2.90 ± 2.65; p = 0.043). In group A, the percentage of patients who had an NRS score of 0 was 51.4% 30 min after surgery, 62.5% after 6 h and 68.1% at POD1, and compared to group B, the NRS scores were significantly higher at POD1 (p = 0.003), and the level of postoperative pain in group A tended to decrease earlier than that in group B. CONCLUSIONS: The results of this study are the first to show that an SGA device can reduce postoperative pain after laparoscopic surgery.

Ground-penetrating radar (GPR) responses for sub-surface salt contamination and solid waste: modeling and controlled lysimeter studies.

The assessment of polluted areas and municipal solid waste (MSW) sites using non-destructive geophysical methods is timely and much needed in the field of environmental monitoring and management. The objectives of this study are (i) to evaluate the ground-penetrating radar (GPR) wave responses as a result of different electrical conductivity (EC) in groundwater and (ii) to conduct MSW stratification using a controlled lysimeter and modeling approach. A GPR wave simulation was carried out using GprMax2D software, and the field test was done on two lysimeters that were filled with sand (Lysimeter-1) and MSW (Lysimeter-2). A Pulse EKKO-Pro GPR system with 200- and 500-MHz center frequency antennae was used to collect GPR field data. Amplitudes of GPR-reflected waves (sub-surface reflectors and water table) were studied under different EC levels injected to the water table. Modeling results revealed that the signal strength of the reflected wave decreases with increasing EC levels and the disappearance of the subsurface reflection and wave amplitude reaching zero at higher EC levels (when EC >0.28 S/m). Further, when the EC level was high, the plume thickness did not have a significant effect on the amplitude of the reflected wave. However, it was also found that reflected signal strength decreases with increasing plume thickness at a given EC level. 2D GPR profile images under wet conditions showed stratification of the waste layers and relative thickness, but it was difficult to resolve the waste layers under dry conditions. These results show that the GPR as a non-destructive method with a relatively larger sample volume can be used to identify highly polluted areas with inorganic contaminants in groundwater and waste stratification. The current methods of MSW dumpsite investigation are tedious, destructive, time consuming, costly, and provide only point-scale measurements. However, further research is needed to verify the results under heterogeneous aquifer conditions and complex dumpsite conditions.

In-situ straining and time-resolved electron tomography data acquisition in a transmission electron microscope.

This paper reports the preliminary results of a new in-situ three-dimensional (3D) imaging system for observing plastic deformation behavior in a transmission electron microscope (TEM) as a directly relevant development of the recently reported straining-and-tomography holder [Sato K et al. (2015) Development of a novel straining holder for transmission electron microscopy compatible with single tilt-axis electron tomography. Microsc. 64: 369-375]. We designed an integrated system using the holder and newly developed straining and image-acquisition software and then developed an experimental procedure for in-situ straining and time-resolved electron tomography (ET) data acquisition. The software for image acquisition and 3D visualization was developed based on the commercially available ET software TEMographyTM. We achieved time-resolved 3D visualization of nanometer-scale plastic deformation behavior in a Pb-Sn alloy sample, thus demonstrating the capability of this system for potential applications in materials science.

Fatal tracheal aspergillosis during rituximab combined chemotherapy for diffuse large B-cell lymphoma that developed after lung transplantation.

Invasive tracheal aspergillosis (ITA) is an infection that is unique to patients who have undergone lung transplantation (LT). Although the activity of this disease often appears on imaging, we encountered a case of ITA that became exacerbated, despite few computed tomography (CT) findings, during rituximab combined chemotherapy for diffuse large B-cell lymphoma. ITA developed during immunosuppressive therapy after LT. Because CT findings may show false-negative results, bronchoscopy is recommended for such cases.

Tumour-suppressive function of SIRT4 in human colorectal cancer.

BACKGROUND: SIRT4, which is localised in the mitochondria, is one of the least characterised members of the sirtuin family of nicotinamide adenine dinucleotide-dependent enzymes that play key roles in multiple cellular processes such as metabolism, stress response and longevity. There are only a few studies that have characterised its function and assessed its clinical significance in human cancers. METHODS: We established colorectal cancer cell lines (SW480, HCT116, and HT29) overexpressing SIRT4 and investigated their effects on proliferation, migration and invasion, as well as E-cadherin expression, that negatively regulates tumour invasion and metastases. The associations between SIRT4 expression in colorectal cancer specimens and clinicopathological features including prognosis were assessed by immunohistochemistry. RESULTS: SIRT4 upregulated E-cadherin expression and suppressed proliferation, migration and invasion through inhibition of glutamine metabolism in colorectal cancer cells. Moreover, SIRT4 expression in colorectal cancer decreased with the progression of invasion and metastasis, and a low expression level of SIRT4 was correlated with a worse prognosis. CONCLUSIONS: SIRT4 has a tumour-suppressive function and may serve as a novel therapeutic target in colorectal cancer.

De novo malignancy after pancreas transplantation in Japan.

BACKGROUND: Long-term immunosuppression is associated with an increased risk of cancer. Especially, the immunosuppression in pancreas transplantation is more intensive than that in other organ transplantation because of its strong immunogenicity. Therefore, it suggests that the risk of post-transplant de novo malignancy might increase in pancreas transplantation. However, there have been few studies of de novo malignancy after pancreas transplantation. The aim of this study was to analyze the incidence of de novo malignancy after pancreas transplantation in Japan. METHODS: Post-transplant patients with de novo malignancy were surveyed and characterized in Japan. RESULTS: Among 107 cases receiving pancreas transplantation in Japan between 2001 and 2010, de novo malignancy developed in 9 cases (8.4%): post-transplant lymphoproliferative disorders in 6 cases, colon cancer in 1 case, renal cancer in 1 case, and brain tumor in 1 case. CONCLUSIONS: We clarified the incidence of de novo malignancy after pancreas transplantation in Japan.

MicroRNA-1246 expression associated with CCNG2-mediated chemoresistance and stemness in pancreatic cancer.

BACKGROUND: Pancreatic cancer has a poor prognosis because of its high refractoriness to chemotherapy and tumour recurrence, and these properties have been attributed to cancer stem cells (CSCs). MicroRNA (miRNA) regulates various molecular mechanisms of cancer progression associated with CSCs. This study aimed to identify the candidate miRNA and to characterise the clinical significance. METHODS: We established gemcitabine-resistant Panc1 cells, and induced CSC-like properties through sphere formation. Candidate miRNAs were selected through microarray analysis. The overexpression and knockdown experiments were performed by evaluating the in vitro cell growth and in vivo tumourigenicity. The expression was studied in 24 pancreatic cancer samples after laser captured microdissection and by immunohistochemical staining. RESULTS: The in vitro drug sensitivity of pancreatic cancer cells was altered according to the miR-1246 expression via CCNG2. In vivo, we found that miR-1246 could increase tumour-initiating potential and induced drug resistance. A high expression level of miR-1246 was correlated with a worse prognosis and CCNG2 expression was significantly lower in those patients. CONCLUSIONS: miR-1246 expression was associated with chemoresistance and CSC-like properties via CCNG2, and could predict worse prognosis in pancreatic cancer patients.

Clinical outcome of pancreas transplantation from marginal donors in Japan.

In Japan, absolute shortage of donors still continues even after the law allowing organ transplantation from deceased donors came into force in 1997. With the passage of the waiting period after registration for pancreas transplantation (PTx), both deaths and serious cases of diabetic complications necessitating withdrawal of the registration have undoubtedly increased. Therefore, so-called "marginal donor" (MD) has been considered as a potential solution for shortage of donors in Japan. The aim of the present study is to evaluate feasibility of MD in terms of post-PTx outcomes using data from Japan Organ Transplantation Network. A total of 148 PTx were performed from deceased donors in Japan from 2000 to 2012. MD was defined as follows: (1) >45 years old; (2) hemodynamically unstable at harvest using a high-dose dopamine or more than 2 vasopressors; or (3) non-heart-beating status. Postoperative outcomes after PTx were compared between the MD group and the non-MD group. Among the 148 PTx donors, 108 donors (73.0%) satisfied the criteria of MD. Early graft loss of pancreas graft during 3 months post-transplant was observed in 15 patients (10.1%), and the marginality (MD vs non-MD) was not significantly correlated with the early loss of pancreas graft. The overall patient survival of the MD group (1, 3, 5 years: 94.7%, 94.7%, 94.7%) was not significantly different from that of the non-MD group (1, 3, 5 years: 95.0%, 95.0%, 95.0%). Pancreas graft survival in the MD group (1, 3, 5 years: 80.9%, 73.2%, 66.0%) seemed to be slightly lower than that in the non-MD group (1, 3, 5 years: 92.5%, 85.2%, 77.4%), but no statistically significant differences were found between the 2 groups. These results suggest the feasibility of the use of MD for PTx.

A histochemical study of the posterior silk glands of Bombyx mori during metamorphosis from larvae to pupae using frozen sections.

The fine structures of the whole bodies and the posterior silk glands of Bombyx mori during metamorphosis from larvae to pupae in the cocoon were preserved virtually without damage when frozen sections were prepared using an adhesive plastic film. We used frozen sections for histochemical and enzyme histochemistry to characterize the metamorphosis of the posterior silk glands. Frozen sections were stained with DAPI to observe nuclear changes, examined using the TUNEL method to detect DNA fragments, and investigated using in situ hybridization to detect B. mori caspase expression. Both DNA fragments and expression of B. mori caspase increased with progressing metamorphosis. The degeneration of the posterior silk gland during metamorphosis appears to be an apoptotic event.

miR-320c regulates gemcitabine-resistance in pancreatic cancer via SMARCC1.

BACKGROUND: Gemcitabine-based chemotherapy is the standard treatment for pancreatic cancer. However, the issue of resistance remains unresolved. The aim of this study was to identify microRNAs (miRNAs) that govern the resistance to gemcitabine in pancreatic cancer. METHODS: miRNA microarray analysis using gemcitabine-resistant clones of MiaPaCa2 (MiaPaCa2-RGs), PSN1 (PSN1-RGs), and their parental cells (MiaPaCa2-P, PSN1-P) was conducted. Changes in the anti-cancer effects of gemcitabine were studied after gain/loss-of-function analysis of the candidate miRNA. Further assessment of the putative target gene was performed in vitro and in 66 pancreatic cancer clinical samples. RESULTS: miR-320c expression was significantly higher in MiaPaCa2-RGs and PSN1-RGs than in their parental cells. miR-320c induced resistance to gemcitabine in MiaPaCa2. Further experiments showed that miR-320c-related resistance to gemcitabine was mediated through SMARCC1, a core subunit of the switch/sucrose nonfermentable (SWI/SNF) chromatin remodeling complex. In addition, clinical examination revealed that only SMARCC1-positive patients benefited from gemcitabine therapy with regard to survival after recurrence (P=0.0463). CONCLUSION: The results indicate that miR-320c regulates the resistance of pancreatic cancer cells to gemcitabine through SMARCC1, suggesting that miR-320c/SMARCC1 could be suitable for prediction of the clinical response and potential therapeutic target in pancreatic cancer patients on gemcitabine-based therapy.

Amorfrutin B is an efficient natural peroxisome proliferator-activated receptor gamma (PPARγ) agonist with potent glucose-lowering properties.

AIMS/HYPOTHESIS: The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) is an important gene regulator in glucose and lipid metabolism. Unfortunately, PPARγ-activating drugs of the thiazolidinedione class provoke adverse side effects. As recently shown, amorfrutin A1 is a natural glucose-lowering compound that selectively modulates PPARγ. In this study we aimed to characterise, in vitro, a large spectrum of the amorfrutins and similar molecules, which we isolated from various plants. We further studied in vivo the glucose-lowering effects of the so far undescribed amorfrutin B, which featured the most striking PPARγ-binding and pharmacological properties of this family of plant metabolites. METHODS: Amorfrutins were investigated in vitro by binding and cofactor recruitment assays and by transcriptional activation assays in primary human adipocytes and murine preosteoblasts, as well as in vivo using insulin-resistant high-fat-diet-fed C57BL/6 mice treated for 27 days with 100 mg kg(-1) day(-1) amorfrutin B. RESULTS: Amorfrutin B showed low nanomolar binding affinity to PPARγ, and micromolar binding to the isotypes PPARα and PPARß/δ. Amorfrutin B selectively modulated PPARγ activity at low nanomolar concentrations. In insulin-resistant mice, amorfrutin B considerably improved insulin sensitivity, glucose tolerance and blood lipid variables after several days of treatment. Amorfrutin B treatment did not induce weight gain and furthermore showed liver-protecting properties. Additionally, amorfrutins had no adverse effects on osteoblastogenesis and fluid retention. CONCLUSIONS/INTERPRETATION: The application of plant-derived amorfrutins or synthetic analogues thereof constitutes a promising approach to prevent or treat complex metabolic diseases such as insulin resistance or type 2 diabetes.

Effect of highly lipolyzed goat cheese on HL-60 human leukemia cells: antiproliferative activity and induction of apoptotic DNA damage.

To establish cheese as a dairy product with health benefits, we embarked on examining the multifunctional role of cheeses, especially in the field of cancer prevention. The current study was designed to investigate whether different types of commercial goat cheeses may possess antiproliferative activity, using an HL-60 human promyelocytic leukemia cell line as a cancer cell model. Among 11 cheese extracts tested at 500µg/mL, 6 (Crottin de Chavignol, Pouligny Saint-Pierre, Chabichou du Poitou, Valencay, Kavli, and Sainte-Maure de Touraine) resulted in a significant decrease of cell viability, which is consistent with a decrease in viable cell number. Compared with the half-maximal inhibitory concentration (IC(50)) value of individual cheeses in cellular proliferation assays, the Pouligny Saint-Pierre extract showed strong inhibition. Incubation of cells in the presence of Pouligny Saint-Pierre extract resulted in induction of cellular morphological changes and apoptotic DNA fragmentation as well as expression of the active form of caspase-3 protein. Based on the quantification of the ratio of free fatty acids to triglycerides in different cheese samples, a significant correlation was detected between lipolytic ripeness and IC(50) values for antiproliferative capacity tested in HL-60 cells. Collectively, these results support a potential role of highly lipolyzed goat cheeses in the prevention of leukemic cell proliferation.

Inhibitory effects of dopamine on spinal synaptic transmission via dopamine D1-like receptors in neonatal rats.

BACKGROUND AND PURPOSE: Dopamine released from the endings of descending dopaminergic nerve fibres in the spinal cord may be involved in modulating functions such as locomotion and nociception. Here, we examined the effects of dopamine on spinal synaptic transmissions in rats. EXPERIMENTAL APPROACH: Spinal reflex potentials, monosynaptic reflex potential (MSR) and slow ventral root potential (sVRP), were measured in the isolated spinal cord of the neonatal rat. Dopamine release was measured by HPLC. KEY RESULTS: Dopamine at lower concentrations (<1 µM) depressed sVRP, which is a C fibre-evoked polysynaptic response and believed to reflect nociceptive transmission. At higher concentrations (>1 µM), in addition to a potent sVRP depression, dopamine depolarized baseline potential and slightly depressed MSR. Depression of sVRP by dopamine was partially reversed by dopamine D(1) -like but not by D(2) -like receptor antagonists. SKF83959 and SKF81297, D(1) -like receptor agonists, and methamphetamine, an endogenous dopamine releaser, also caused the inhibition of sVRP. Methamphetamine also depressed MSR, which was inhibited by ketanserin, a 5-HT(2A/2C) receptor antagonist. Methamphetamine induced the release of dopamine and 5-HT from spinal cords, indicating that the release of endogenous dopamine and 5-HT depresses sVRP and MSR respectively. CONCLUSION AND IMPLICATIONS: These results suggested that dopamine at lower concentrations preferentially inhibited sVRP, which is mediated via dopamine D(1) -like and other unidentified receptors. The dopamine-evoked depression is involved in modulating the spinal functions by the descending dopaminergic pathways.

Computerised 3-D anatomical modelling using plastinates: an example utilising the human heart.

Computerised modelling methods have become highly useful for generating electronic representations of anatomical structures. These methods rely on crosssectional tissue slices in databases such as the Visible Human Male and Female, the Visible Korean Human, and the Visible Chinese Human. However, these databases are time consuming to generate and require labour-intensive manual digitisation while the number of specimens is very limited. Plastinated anatomical material could provide a possible alternative to data collection, requiring less time to prepare and enabling the use of virtually any anatomical or pathological structure routinely obtained in a gross anatomy laboratory. The purpose of this study was to establish an approach utilising plastinated anatomical material, specifically human hearts, for the purpose computerised 3-D modelling. Human hearts were collected following gross anatomical dissection and subjected to routine plastination procedures including dehydration (-25(o)C), defatting, forced impregnation, and curing at room temperature. A graphics pipeline was established comprising data collection with a hand-held scanner, 3-D modelling, model polishing, file conversion, and final rendering. Representative models were viewed and qualitatively assessed for accuracy and detail. The results showed that the heart model provided detailed surface information necessary for gross anatomical instructional purposes. Rendering tools facilitated optional model manipulation for further structural clarification if selected by the user. The use of plastinated material for generating 3-D computerised models has distinct advantages compared to cross-sectional tissue images.