Effects of Radiation Doses on Clinical Recurrence in Patients with Biochemically Recurrent Prostate Cancer after Prostatectomy

PURPOSE/OBJECTIVE(S)

Salvage radiotherapy (SRT) to the prostate bed is the only curative treatment for patients with biochemical recurrence (BCR) after radical prostatectomy (RP). Although several systematic reviews indicated that a dose escalation in the range of 60-70 Gy improved biochemical control, the effects of radiation doses on clinical relapse after SRT remain unclear. Our aim was to investigate the relationship between radiation doses and clinical relapse-free survival (cRFS) after SRT.

MATERIALS/METHODS

We identified 295 eligible patients receiving SRT for biochemically recurrent prostate cancer after RP between 2005 and 2018 at 15 institutions. Sixteen patients (5%) received short-term (< 6 months) androgen deprivation therapy (ADT) following RP and/or concurrently with SRT. SRT was delivered to the prostate and seminal vesicle bed using photon beams at a median (range) dose of 66 Gy (61-85) in 1.8-3.0 Gy fractions. The primary outcome was cRFS. Clinical relapse was identified on radiological imaging and/or biopsy and included local recurrence, lymph node metastasis, and distant metastasis. In all analyses, doses were recalculated as an equivalent dose in 2-Gy fractions (EQD2) with α/β = 1.5 Gy. Clinical RFS between the EQD2 ≥ 66 Gy (n = 229) and EQD2 < 66 Gy (n = 66) groups were compared using the Log-rank test, followed by univariate and multivariate Cox regression analyses and a subgroup analysis.

RESULTS

The median follow-up duration was 73 months. Among patients with BCR (n = 119), 79 of 96 (82%) in the EQD2 ≥ 66 Gy group and 21 of 23 (91%) in the EQD2 < 66 Gy group received second salvage ADT (p = 0.36). Among all patients (n = 295), clinical relapse was identified in 22 (7%) patients after SRT. Six-year biochemical relapse-free survival (bRFS), cRFS, cancer-specific survival (CSS), and overall survival (OS) rates were 58%, 93%, 98%, and 94%, respectively. Six-year cRFS rates were 94% (95% confidence interval [CI], 90-97) in the EQD2 ≥ 66 Gy group and 87% (95% CI, 75-93) in the EQD2 < 66 Gy group (p = 0.020). The multivariate analysis revealed that EQD2 < 66 Gy, Gleason score ≥ 8, seminal vesicle involvement, and PSA at BCR ≥ 0.5 ng/ml correlated with clinical relapse (p = 0.0016, 0.014, 0.011, and 0.027, respectively). The subgroup analysis showed the consistent benefit of EQD2 ≥ 66 Gy in patients across most subgroups including PSA at BCR after RP, extracapsular extension, and age at SRT.

CONCLUSION

This large multi-institutional observational study demonstrated that a higher SRT dose (EQD2 ≥ 66 Gy) resulted in superior cRFS. The present result supports the dose recommendations in the 2023 National Comprehensive Cancer Network guidelines (64-72 Gy) even in terms of clinical relapse. Prospective trial is warranted to investigate an upper threshold for optimal SRT dose.

Contributions of small dense LDL and oxidized LDL on the formation of neoatherosclerosis in patients under statin treatment

Aim

In-stent neoatherosclerosis (NA) has emerged as an important contributing factor to late stent failure and cardiovascular events. The aim of this study was to investigate whether lipid markers are associated with NA using optical coherence tomography (OCT) after percutaneous coronary intervention (PCI) in patients with coronary artery disease under well-controlled low density lipoprotein cholesterol (LDL-c) on statin treatment.

Methods

We enrolled consecutive 115 patients under statin treatment who underwent PCI with current-generation drug-eluting stent for acute and chronic coronary syndrome. OCT image and various lipid markers were obtained at 1-year for scheduled research assessment. NA was defined as a lipid laden neointima or calcified neointima. Both small dense LDL-c (sd-LDL-c) and remnant lipoprotein cholesterol (RL-c) were measured using direct homogenous assay.

Results

During an average follow-up of 13 months, NA was observed in 14 (13.6%) patients. Not LDL-c but sd-LDL-c, Malondialdehyde-modified LDL (MDA-LDL) as oxidized LDL and (RL-c) were significantly higher in patients with NA. The optimal threshold values of sd-LDL-c, MDA-LDL and RL-c for predicting NA according to receiver operating characteristics analysis were 32.3 mg/dl, 91.0 U/L, and 3.3 mg/dL, respectively. On multivariate logistic regression analysis, sd-LDL-c (≥32.3 mg/dL) and MDA (≥91.0 U/L) were significantly associated with NA (odds ratio [OR]:13.62, p=0.016, OR: 12.68, p=0.01, respectively).

Conclusions

In statin-treated patients, sd-LDL-c and MDA-LDL but not LDL-c might be useful biomarkers to identify the formation of NA at 1 years after PCI. Aggressive reduction of these atherogenic LDL may have a potential to prevent the formation of NA.

Funding Acknowledgement

Type of funding sources: None.

Higher plasma level of small dense low-density lipoprotein cholesterol in ST-segment-elevation myocardial infarction patients with plaque rupture

Aim

The aim of this study was to compare small dense low-density lipoprotein cholesterol (sd-LDL-c) and various lipid markers between patients exhibiting plaque rupture (PR) in the culprit lesions evaluated by optical coherence tomography (OCT) imaging and those without PR in ST-segment elevation myocardial infarction (STEMI) patients.

Methods

We studied consecutive 60 de novo culprit lesions in 60 patients with STEMI who underwent pre-intervention OCT. PR was defined as a plaque containing a cavity that had overlying residual fibrous caps. Plasma sd-LDL-c was measured directly by homogeneous assay at the time of primary percutaneous coronary intervention.

Results

The patients were classified into PR (n=40, 66.7%) or non-PR (n=20, 33.3%). There were no significant differences in low-density lipoprotein cholesterol (LDL-c), non-high-density lipoprotein cholesterol (non-HDL-c) and pre-admission statin therapy between two groups (135.1±38.0 mg/dL vs 129.2±43.8 mg/dL; p=0.35, 157.1±37.4 mg/dL vs 143.0±37.7 mg/dL; p=0.24, 15.0% vs 20.0%; p=0.93). However, sd-LDL-c level was significantly higher in patients with PR than those with non-PR (44.0±18.1 mg/dL vs 28.0±9.3 mg/dL; p=0.0005). On multiple logistic regression analysis, sd-LDL-c was an independent predictor of PR (odds ratio, 1.14 per 1 mg/dL; p=0.0063).

Conclusion

Sd-LDL-c was significantly associated with PR of the culprit lesion in patients with STEMI.

Funding Acknowledgement

Type of funding sources: None.

Early vascular healing following bioresorbable-polymer sirolimus-eluting stent implantation in comparison with durable-polymer everolimus-eluting stent: sequential optical coherence tomography study

Background

Orsiro ultrathin-strut bioresorbable-polymer sirolimus-eluting stent (BP-SES) might facilitate early vascular healing responses that seems to be associated with improved long-term clinical outcomes. We compared the early vascular healing responses to BP-SES and Xience durable-polymer everolimus-eluting stent (DP-EES) in patients with chronic coronary syndrome (CCS) using optical coherence tomography (OCT).

Methods

A total of 40 patients with CCS receiving OCT-guided PCI were included. 20 patients were assigned to BP-SES, and 20 to DP-EES. OCT was performed immediately after stent placement (post-procedure) and at 1 month follow-up. Struts were recorded as uncovered if any part was visibly exposed in the lumen or covered if a layer of tissue covered all reflecting surfaces. The incidence of intrastent thrombus (IS-Th) and irregular protrusion (IRP) were also assessed.

Results

At 1 month, the percentage of uncovered struts was significantly lower in the BP-SES compared with the DP-EES (2.8±1.6% vs. 5.8±1.8%, respectively; p&lt;0.001), and that of malapposed struts was similar between both groups (2.5±3.1% vs. 2.4±2.2%; p=0.76). There were no differences in the incidence of IS-Th (65.0% vs. 55.0% at post-procedure; p=0.54, 30.0% vs. 35.0% at 1 month; p=0.75) and IRP (30.0% vs. 25.0% at post-procedure; p=0.74). IRP had completely resolved at 1 month in both groups.

Conclusion

Early vascular healing response to Orsiro BP-SES implantation was revealed in CCS patients at 1 month compared with Xience DP-EES. Orsiro BP-SES may have a potential to shorten the dual antiplatelet therapy duration.

Funding Acknowledgement

Type of funding source: None

Early vascular responses to ultrathin biodegradable polymer sirolimus-eluting stent for the treatment of st-elevation myocardial infarction

Background

Recent clinical study suggests newer-generation drug-eluting stents (DES) that combine ultrathin strut and nano-coating with biodegradable polymers sirolimus-eluting stent (BP-SES) could improve long-term clinical outcomes in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) over current generation DES. However, safety profiles in very early phase have not been systematically addressed.

Objective and method

We exploratory investigate early vascular response following BP-SES implantation in patients with STEMI to reveal mechanism of the favorable clinical outcomes in recent studies using frequency domain-optical coherence tomography (FD-OCT).

Consecutive twenty patients with STEMI who underwent FD-OCT immediately after primary PCI and were eligible for follow-up FD-OCT at 2 weeks after implantation were enrolled between June 2018 and November 2019.

Results

Twenty patients (age 62.7±11.3 years, male 85.0%) were enrolled with frequencies of hypertension (45.0%), diabetes mellitus (35.0%), dyslipidemia (55.0%) and smoking (80.0%). Aspiration catheter were used in all patients, and 1.13±0.34 stents were used. Only one patient (5.0%) received chronic antiplatelet therapy with aspirin prior to the onset of STEMI. All patients started to receive prasugrel as thienopyridine from this event and continued dual antiplatelet therapy for 2 weeks.

The percentage of uncovered struts significantly decreased from post-procedure to 2W follow-up (69±18% post-procedure versus 30±11% at 2W follow up, p&lt;0.0001). Malapposed struts also decreased (5.6±5.7% post-procedure versus0.9±1.2% at 2W follow up, p&lt;0.0001).The average protrusion area of athero-thrombotic burden numerically decreased (0.37±0.19 at post-procedure versus 0.34±0.14 mm2 at 2W follow up, p=0.19) and its volume showed similar tendency (10.60±6.40 at post-procedure versus 9.36±5.14 mm3 at 2W follow up, p=0.19).

Conclusion(s)

This study firstly elucidated very early vascular responses following ultrathin strut BP-SES implantation in STEMI patients, showing early progression of strut coverage and resolution of athero-thrombotic materials. This technology may have a potential to overcome the current generation DESs in this clinical setting.

Thrombus, uncovered and malapposed struts

Funding Acknowledgement

Type of funding source: None

Safety of tapering tacrolimus dose in patients with well-controlled anti-acetylcholine receptor antibody-positive myasthenia gravis

BACKGROUND AND PURPOSE

Tapering immunosuppressants is desirable in patients with well-controlled myasthenia gravis (MG). However, the association between tapering of calcineurin inhibitor dosage and reduction-associated exacerbation is not known. The aim of this study was to clarify the frequency of reduction-associated exacerbation when tacrolimus is tapered in stable patients with anti-acetylcholine receptor antibody-positive MG, and to determine the factors that predict exacerbations.

METHODS

We retrospectively analyzed 115 patients in whom tacrolimus dosage was tapered. The reduction-associated exacerbation was defined as the appearance or worsening of one or more MG symptoms <3 months after the reduction.

RESULTS

Tacrolimus dosage was successfully tapered in 110 patients (96%) without any exacerbation. Five patients (4%) experienced an exacerbation, but symptoms were reversed in all patients when the tacrolimus dose was increased to the previous maintenance level. No patient developed an MG crisis. The age at onset was significantly earlier (30 vs. 56 years, P = 0.025) and the reduction in dosage was significantly larger (2.0 vs. 1.0 mg/day, P = 0.002) in patients with reduction-associated exacerbation than in those without exacerbation. The cut-off values determined in a receiver-operating characteristic curve analysis were 52 years (sensitivity, 57%; specificity, 100%) for the age at onset and 1.5 mg (sensitivity, 80%; specificity, 100%) for the dose reduction.

CONCLUSION

Tapering of tacrolimus was possible in most patients with well-controlled anti-acetylcholine receptor antibody-positive MG. Early age at onset and a large reduction from maintenance dosage were associated with exacerbation. Reductions ≤1.5 mg/day from the maintenance dosage should be considered for patients with late-onset disease.

VALIDATION OF MONTE CARLO DOSE CALCULATION FOR PAEDIATRIC CT EXAMINATIONS USING TUBE CURRENT MODULATION BASED ON IN-PHANTOM DOSIMETRY

The aim of this study is to estimate tube current modulation (TCM) profiles in paediatric computed tomography (CT) examinations with a TCM scheme (Volume-EC) and evaluate the estimation accuracy of TCM profiles. Another aim is to validate organ doses calculated using Monte Carlo-based CT dosimetry software and estimated TCM profiles by comparing them with those measured using 5-year-old and 10-year-old anthropomorphic phantoms and radio-photoluminescence glass dosemeters. Dose calculations were performed by inputting detailed descriptions of a CT scanner, scan parameters and CT images of the phantoms into the software. Organ doses were evaluated from the calculated dose distribution images. Average relative differences (RDs) between the estimated and actual TCM profiles ranged from -3.6 to 5.6%. RDs between the calculated and measured organ doses ranged from -4.2 to 13.0% and -18.1 to 4.9% for 5-year-old and 10-year-old phantoms, respectively. These results validate dose calculations for paediatric CT scans using TCM.

Weak localization in bilayer graphene with Li-intercalation/desorption

We performed in-situ electrical transport measurements for bilayer graphene grown on SiC(0 0 0 1) substrate, Li-intercalated bilayer graphene, and after that desorbing Li atoms by heating. Bilayer graphene after desorbing intercalated Li atoms showed a higher resistivity and different behavior in magnetoconductance compared to pristine bilayer graphene. We observed the weak localization of carriers at low temperatures in all the three samples and analyzed the experimental results with the extended Hikami-Larkin-Nagaoka equation to investigate the transport properties. The result shows that the magnetoconductance of pristine bilayer graphene is described by the AB stacking structure model and the phase breaking scattering is dominated by the electron-electron scattering. The intra-valley scattering occurs most frequently probably due to dopants in SiC substrate. However, in Li-desorbed graphene, the magnetoconductance can be described by neither AB nor AA-stacking model, suggesting the coexistence of domains with several different stacking structures.

Vascular density of superficial esophageal squamous cell carcinoma determined by direct observation of resected specimen using narrow band imaging with magnifying endoscopy

Observation of the microvasculature using narrow band imaging (NBI) with magnifying endoscopy is useful for diagnosing superficial squamous cell carcinoma. Increased vascular density is indicative of cancer, but not many studies have reported differences between cancerous and noncancerous areas based on an objective comparison. We observed specimens of endoscopic submucosal dissection (ESD) using NBI magnification, and determined the vascular density of cancerous and noncancerous areas. A total of 25 lesions of esophageal squamous cell carcinoma that were dissected en bloc by ESD between July 2013 and December 2013 were subjected to NBI magnification. We constructed a device that holds an endoscope and precisely controls the movement along the vertical axis in order to observe submerged specimens by NBI magnification. NBI image files of both cancerous (pathologically determined invasion depth, m1/2) and surrounding noncancerous areas were created and subjected to vascular density assessment by two endoscopists who were blinded to clinical information. The invasion depth was m1/2 in 20, m3/sm1 in four and sm2 in one esophageal cancer lesion. Mean vascular density was significantly increased in cancerous areas (37.6 ± 16.3 vessels/mm2) compared with noncancerous areas (17.6 ± 10.0 vessels/mm2) (P < 0.05). The correlation coefficients between vascular density determined by two endoscopists were 0.86 and 0.81 in cancerous and noncancerous areas, respectively. Receiver operating curve (ROC) analysis revealed that the area under the curve (AUC) of vascular density was 0.895 (95% CI, 0.804-0.986). For this ROC curve, sensitivity was 78.3% and specificity was 87.0% when the cutoff value of vascular density was 26 vessels/mm2. NBI magnification confirmed significant increases in vascular density in cancerous areas compared with noncancerous areas in esophageal squamous cell carcinoma. The rates of agreement between vascular density values determined by two independent operators were high.

Organ Dose Evaluations Based on Monte Carlo Simulation for CT Examinations Using Tube Current Modulation

The aims of this study were to estimate tube current values for each X-ray projection angle used in adult chest computed tomography (CT) and abdomen-pelvis CT examinations with tube current modulation (TCM) and to validate organ doses determined using Monte Carlo (MC) simulations through comparisons with the doses measured using in-phantom dosimetry. For dose simulations, dose distribution images were obtained by inputting the geometry of a CT scanner, scan parameters including estimated TCM curves and CT images of an adult anthropomorphic phantom into MC simulation software. Organ doses were then determined from the dose distribution images. For dose measurements, organ doses were evaluated using radio-photoluminescence glass dosemeters located at various organ positions within the phantom. Relative differences between the simulated and measured organ doses were -2.5 to 11.0% and -1.5 to 10.5% for organs in chest and abdomen-pelvis CT scan ranges, respectively. Thus, the simulated and measured doses agreed well.

Anisotropic atomic-structure related anomalous Hall resistance in few-layer black phosphorus

Specific anisotropic-atomic-structure of atom-thin black phosphorus causes the anomalous magnetic-field dependence of the Hall resistance, which opens doors to novel quantum phenomena and innovative two-dimensional atom-thin devices.

Inhibition of Trigeminal Respiratory Activity by Suckling

The trigeminal motor system is involved in many rhythmic oral-motor behaviors, such as suckling, mastication, swallowing, and breathing. Despite the obvious importance of functional coordination among these rhythmic activities, the system is not well-understood. In the present study, we examined the hypothesis that an interaction between suckling and breathing exists in the brainstem, by studying the respiratory activity in trigeminal motoneurons (TMNs) during fictive suckling using a neonatal rat in vitro brainstem preparation. The results showed that fictive suckling, which was neurochemically induced by bath application of N-methyl-D,L-aspartate and bicuculline-methiodide, or by local micro-injection of the same drugs to the trigeminal motor nucleus, inhibited the inspiratory activities in both respiration TMNs and respiratory rhythm-generating neurons. Under patch-clamp recording, fictive suckling caused membrane potential hyperpolarization of respiration TMNs. We conclude that the brainstem preparation contains an inhibitory circuit for respiratory activity in the trigeminal motor system via the rhythm-generating network for suckling. Abbreviations: BIC, bicuculline methiodide; GABA, gamma aminobutyric acid; NMA, N-methyl-D,L-aspartate; NMDA, N-methyl-D-aspartate; and TMN, trigeminal motoneuron.

The Relationship between Psychotropic Drug Use and Suicidal Behavior in Japan: Japanese Adverse Drug Event Report

Introduction: Very few studies have explored the adverse effect of psychotropic drugs worldwide. Methods: This study analyzed 1 813 suicide-related drug reports involving 553 patients collected from the Japanese National Adverse Drug Report Database between October 2001 and January 2012 to investigate psychotropic drugs associated with completed suicide vs. other suicide-related behaviors, including ideation and self-injury. The drugs investigated included antidepressants, antipsychotics, benzodiazepines, non-benzodiazepine hypnotic agents, noradrenergic and specific serotonergic antidepressants, selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, and other drugs. Results: These reports referenced 300 (54.2%) individuals who completed suicide. Adjusting for age, sex, and drugs used, the multivariate model revealed that participants who took antipsychotics were 1.70 times (95% CI, 1.11-2.61) more likely to complete suicide compared with those who did not. All other drugs became non-significant. Compared with those who took only one medication, those prescribed more than 4 drugs were more likely to complete suicide (OR 4.44, 95% CI, 2.40-8.20). Discussion: Antipsychotic drugs and polypharmacy may be regarded as predictors of completed suicide.

Amyloid-Producing Odontogenic Tumors of the Facial Skin in Three Cats

Amyloid-producing odontogenic tumors (APOTs) of the facial skin were diagnosed in 3 domestic cats. The neoplasms had the histopathological characteristics of the odontogenic tumor. The neoplastic cells were present in irregular islands, strands, and sheets. The peripheral neoplastic cells of the islands and strands were arranged in a palisading fashion, while the central cells were polyhedral to stellate and randomly arranged. Multiple spherules of homogeneous eosinophilic material were closely apposed to the neoplastic epithelial cells. The spherules stained with Congo red and produced an apple green birefringence under polarization microscopy, indicative of amyloid. Immunohistochemically, amyloid materials of the neoplasms reacted with polyclonal antibodies for ameloblastin, amelogenin, and sheathlin antibodies. Neoplastic epithelial cells also reacted with antiameloblastin, amelogenin, and sheathlin antibodies, with varied intensity. The histopathological and immunohistochemical characteristics of dermal neoplasms of the 3 cats were analogous to those of APOTs reported in the dog and the cat.

T-Cell Lymphoma with Eosinophilic Infiltration Involving the Intestinal Tract in 11 Dogs

Among the intestinal tumors of hematopoietic cell origin, lymphoma is the most common in the dog. Herein, we characterized the clinical and pathologic features of 11 dogs (average age, 10.6 ± 2.5 years) with T-cell lymphoma of the intestinal tract with eosinophil infiltrates. No sex predominance was apparent. All had localized tumor masses in the small intestine. Grossly, the intestinal wall was thickened, and the lumen of the affected intestine was usually narrowed. Microscopically, we observed transmural diffuse invasion of round to pleomorphic tumor cells. Tumor cells showed varying morphology, from scanty to abundant cytoplasm, and round to ovoid nuclei with scattered to dense chromatin. In seven of the dogs, tumor cells had infiltrated into the epithelium. All showed infiltration of eosinophils and all 11 tumors had a T-cell phenotype (CD3+,CD79-). Only one tumor stained positive for the mast cell marker c-kit and none was positive for mast cell tryptase. We did not observe ultrastructurally apparent granules in any of the tumor cells. These results suggest that, in dogs, T-cell lymphomas of intestinal origin resemble mast cell tumors of intestinal origin with respect to cell structure and eosinophil infiltration. Therefore, in the absence of epitheliotropism, it is difficult to confirm the differential diagnosis without immunostaining for mast cell and lymphocyte markers, including mast cell tryptase, c-kit, CD3, and CD79.

Mast Cell Tumors of the Gastrointestinal Tract in 39 Dogs

Mast cell tumors (MCTs) of gastrointestinal origin that had been surgically removed from 39 dogs were examined to evaluate their pathologic features. Miniature breeds, especially Maltese, were most frequently affected. The average age of affected dogs was 9.7 ± 2.6 years. No sex difference was apparent. The most frequently affected sites were in the upper digestive tract, and the prognosis was very poor. Grossly, the gastrointestinal wall was prominently thickened, and the lumen of the affected gut was usually narrowed. Microscopically, there was diffuse transmural invasion of round to pleomorphic tumor cells. Tumor cells had moderate to abundant cytoplasm, round to ovoid nuclei with scattered chromatin, and mitotic figures. Fibrous stroma was observed in about half of the tumors. There was variable infiltration of eosinophils. In all tumors, cytoplasmic granules showed weak metachromasia, but the number of granules was very small. Immunohistochemical staining for c-kit and mast cell tryptase was positive in 77% and 62% of tumors, respectively. All tumors were positive for at least two of these markers. Immunohistochemical staining for p53 was positive in 13% of the tumors. Reactivity for staining markers and p53 was unrelated to cell pleomorphism, vessel invasion, or survival time. Gastrointestinal MCTs have histologic and immunohistochemical features completely different from those of other primary or metastatic gastrointestinal tumors. The combination of immunostaining for mast cell tryptase and c-kit and histochemical staining for metachromasia appears to be a powerful tool for the diagnosis of gastrointestinal MCTs.

Electromagnetic Fields Inhibit Endothelin-1 Production Stimulated by Thrombin in Endothelial Cells

Electromagnetic field (EMF) radiation has been found to induce arteriolar dilatation, but the mechanism of action remains largely unknown. This study investigated the effect of EMF radiation on the production of endothelin-1 (ET-1), a potent vasoconstrictor, by cultured endothelial cells. EMF radiation reduced ET-1 basal levels in human umbilical vein and microvascular endothelial cells, but failed to reduce ET-1 basal levels in bovine and human aortic endothelial cells. EMF radiation significantly inhibited thrombin-stimulated ET-1 production in all four endothelial cell types in a dose-dependent manner. EMF radiation significantly inhibited thrombin-induced endothelin-1 mRNA expression in all four cell types. The inhibitory effect of EMF radiation on ET-1 production was abolished by the nitric oxide synthase inhibitor NG-monomethyl-L-arginine (10−3 mol/l). These results demonstrate that EMF radiation modulates ET-1 production in cultured vascular endothelial cells and the inhibitory effect of EMF radiation is, at least partly, mediated through a nitric oxide-related pathway.

Spermatogonial Nature of the Germ Cell Component of Canine Testicular Mixed Germ Cell-Sex Cord Stromal Tumours

The present study has characterized the germ cell component of canine testicular mixed germ cell-sex cord stromal tumours (MGSCTs) by examining the histological nature and histochemical and immunohistochemical features using gonocytic and spermatogonial cellular markers, c-Kit, placental alkaline phosphatase (PLAP), protein gene product 9.5 (PGP9.5), Sal-like protein 4 (SALL4), and the periodic acid-Schiff (PAS) reaction. Histologically, all 45 examples of MGSCTs were classified as spermatocytic seminomas (SSs) and Sertoli cell tumours in combination. The germ cell component of all MGSCTs was negative by PAS staining. Immunohistochemically, PLAP immunoreactivity was lacking in the germ cell component of all MGSCTs, which is not consistent with a gonocytic origin. The germ cell component was positive for PGP9.5 and SALL4 in all MGSCTs and positive for c-Kit in 53% of MGSCTs, which is consistent with the phenotype of spermatogonia. Furthermore, the germ cell component in 71% of MGSCTs had moderate immunoreactivity for SALL4, which is suggestive of a spermatogonial phenotype. Conversely, 29% of cases had a minor population of germ cells showing strong SALL4 immunoreactivity, suggesting a phenotype similar to prespermatogonia. The results suggest that the germ cell component of canine MGSCTs is morphologically classified as SS, with the majority of cases showing the spermatogonial phenotype and some cases containing a small population of prespermatogonia.

Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus-the 'D-shuttle' project

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter 'D-shuttle' for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the terrestrial background radiation level of other regions/countries.

Evaluation of organ doses in adult and paediatric CT examinations based on Monte Carlo simulations and in-phantom dosimetry

The aim of this study was to validate the computed tomography dose index (CTDI) and organ doses evaluated by Monte Carlo simulations through comparisons with doses evaluated by in-phantom dosimetry. Organ doses were measured with radio-photoluminescence glass dosemeter (RGD) set at various organ positions within adult and 1-y-old anthropomorphic phantoms. For the dose simulations, the X-ray spectrum and bow-tie filter shape of a CT scanner were estimated and 3D voxelised data of the CTDI and anthropomorphic phantoms from the acquired CT images were derived. Organ dose simulations and measurements were performed with chest and abdomen-pelvis CT examination scan parameters. Relative differences between the simulated and measured doses were within 5 % for the volume CTDI and 13 % for organ doses for organs within the scan range in adult and paediatric CT examinations. The simulation results were considered to be in good agreement with the measured doses.

Spin-electricity conversion induced by spin injection into topological insulators

We report successful spin injection into the surface states of topological insulators by using a spin pumping technique. By measuring the voltage that shows up across the samples as a result of spin pumping, we demonstrate that a spin-electricity conversion effect takes place in the surface states of bulk-insulating topological insulators Bi(1.5)Sb(0.5)Te(1.7)Se(1.3) and Sn-doped Bi(2)Te(2)Se. In this process, the injected spins are converted into a charge current along the Hall direction due to the spin-momentum locking on the surface state.

Right ventricular dynamic cardiomyoplasty for the univentricular heart with pulmonary hypertension

OBJECTIVES

We conducted an acute experimental study to test the feasibility of dynamic cardiomyoplasty in a setting of modified Fontan procedure for univentricular heart with pulmonary hypertension to obtain a possible proxy for high-risk Fontan candidates.

METHODS

After electrical preconditioning of the left latissimuss dorsi for 6 weeks in 8 dogs, the right ventricular cavity was totally obliterated with concomittent closure of the tricuspid valve and right pulmonary artery. Modified Fontan circulation was established with the aortic homograft anastomosed between the right atrium and pulmonary trunk, incorporated with a pericardial pouch as a compression chamber (neoright ventricle) fixed onto the epicardial surface of the ventricle. After cardiopulmonary bypass termination, a latissimus dorsi was applied to wrap the pericardial pouch and ventricle clockwise and stimulated with a trained-pulse (25 Hz) at 1:1 synchronization ratio with cardiac beats.

RESULTS

Profound right heart failure was noted during Fontan circulation in increased pulmonary vascular resistance (11 +/- 3.2 Wood units), whereas graft pacing showed significant augmentation of systolic pulmonary pressure by 54 +/- 12%, the mean pulmonary flow by 68 +/- 23%, and aortic pressure by 23 +/- 5% at a physiological range of central venous pressure (13.2 +/- 0.7 mmHg). Right heart function curve analysis confirmed marked augmentation of right heart performance, restoring almost normal pulmonary circulation. These functional benefits were sustained up to 4 hours in 4 animals until experiments were terminated.

CONCLUSIONS

Dynamic cardiomyoplasty in a modified Fontan procedure is a viable surgical option for univentricular heart, not a Fontan candidate.

Expression of protein gene product 9.5 and Sal-like protein 4 in canine seminomas

The aim of the present study was to characterize canine classical seminoma (SE) and spermatocytic seminoma (SS) by immunohistochemical expression of gonocytic and spermatogonial cellular markers (c-Kit, placental alkaline phosphatase [PLAP], protein gene product 9.5 [PGP9.5] and Sal-like protein 4 [Sall4]) and histochemically by the periodic acid-Schiff (PAS) reaction. Twenty-five cases of SE and 23 cases of SS were investigated. Two cases of dysgerminoma were also examined. c-Kit was expressed on the cell membrane of 13 of 25 cases of SE (52%) and four of 23 cases of SS (16%). This marker was not expressed in dysgerminoma. PLAP immunoreactivity was observed in the cytoplasm of neoplastic cells of six of 25 cases of SE (24%). PLAP was not expressed in cases of SS and dysgerminoma. All samples of SE, SS and dysgerminoma showed cytoplasmic expression of PGP9.5 and nuclear immunoreactivity for Sall4. There was fine granular cytoplasmic PAS staining in neoplastic cells in five of 25 cases of SE (20%), while all samples of SS and dysgerminoma cases were PAS negative. These findings suggest that it is not possible to differentiate canine SE and SS using these markers. This may be because canine SS may be derived from spermatogonia that can differentiate to spermatocytes and also because cases of canine SE might consist of neoplastic cells that have lost their gonocytic nature. This study was the first to show positive immunoreactivity for Sall4 in canine seminomas and dysgerminomas and expression of PGP9.5 in canine dysgerminomas.

Reconstructing the origin and dispersal patterns of village chickens across East Africa: insights from autosomal markers

Unravelling the genetic history of any livestock species is central to understanding the origin, development and expansion of agricultural societies and economies. Domestic village chickens are widespread in Africa. Their close association with, and reliance on, humans for long-range dispersal makes the species an important biological marker in tracking cultural and trading contacts between human societies and civilizations across time. Archaezoological and linguistic evidence suggest a complex history of arrival and dispersion of the species on the continent, with mitochondrial DNA (mtDNA) D-loop analysis revealing the presence of five distinct haplogroups in East African village chickens. It supports the importance of the region in understanding the history of the species and indirectly of human interactions. Here, through a detailed analysis of 30 autosomal microsatellite markers genotyped in 657 village chickens from four East African countries (Kenya, Uganda, Ethiopia and Sudan), we identify three distinct autosomal gene pools (I, II and III). Gene pool I is predominantly found in Ethiopia and Sudan, while II and III occur in both Kenya and Uganda. A gradient of admixture for gene pools II and III between the Kenyan coast and Uganda's hinterland (P = 0.001) is observed, while gene pool I is clearly separated from the other two. We propose that these three gene pools represent genetic signatures of separate events in the history of the continent that relate to the arrival and dispersal of village chickens and humans across the region. Our results provide new insights on the history of chicken husbandry which has been shaped by terrestrial and maritime contacts between ancient and modern civilizations in Asia and East Africa.