LET Dependence of 8-Hydroxy-2'-deoxyguanosine (8-OHdG) Generation in Mammalian Cells under Air-Saturated and Hypoxic Conditions: A Possible Experimental Approach to the Mechanism of the Decreasing Oxygen Effect in the High-LET Region

One of the most distinguished features in biological effects of heavy ions would be the decrease of oxygen effect in the high-LET region. This feature has been referred to as the radiobiological basis for the control of hypoxic fraction in cancer radiotherapy. However, mechanisms to explain this phenomenon have not been fully understood. One of the explanations was given by the oxygen in the track hypothesis, which proposes that oxygen is produced along ion tracks even in the hypoxic irradiation condition. In the present study, we designed an experimental approach to support this hypothesis by using 8-hydroxy-2'-deoxyguanosine (8-OHdG) as DNA damage requiring oxygen to produce. The LET dependence of 8-OHdG under hypoxic condition revealed that with increasing LET 8-OHdG yield seems to increase, despite that the yield of OH radical, which is also required for the production of 8-OHdG, decreases in the high-LET region. This result is consistent with the explanation that the local generation of oxygen along ion tracks contributes to the increase of 8-OHdG yield.

Open-label phase II study of the efficacy of nivolumab for cancer of unknown primary

BACKGROUND

Cancer of unknown primary (CUP) has a poor prognosis. Given the recent approval of immune checkpoint inhibitors for several cancer types, we carried out a multicenter phase II study to assess the efficacy of nivolumab for patients with CUP.

PATIENTS AND METHODS

Patients with CUP who were previously treated with at least one line of systemic chemotherapy constituted the principal study population. Previously untreated patients with CUP were also enrolled for exploratory analysis. Nivolumab (240 mg/body) was administered every 2 weeks for up to 52 cycles. The primary endpoint was objective response rate in previously treated patients as determined by blinded independent central review according to RECIST version 1.1.

RESULTS

Fifty-six patients with CUP were enrolled in the trial. For the 45 previously treated patients, objective response rate was 22.2% [95% confidence interval (CI), 11.2% to 37.1%], with a median progression-free survival and overall survival of 4.0 months (95% CI, 1.9-5.8 months) and 15.9 months (95% CI, 8.4-21.5 months), respectively. Similar clinical benefits were also observed in the 11 previously untreated patients. Better clinical efficacy of nivolumab was apparent for tumors with a higher programmed death-ligand 1 expression level, for those with a higher tumor mutation burden, and for microsatellite instability-high tumors. In contrast, no differences in efficacy were apparent between tumor subgroups based on estimated tissue of origin. Adverse events were consistent with the known safety profile of nivolumab. No treatment-related death was observed.

CONCLUSIONS

Our results demonstrate a clinical benefit of nivolumab for patients with CUP, suggesting that nivolumab is a potential additional therapeutic option for CUP.

Radiation doses of workers engaged in decontamination of the environment

After the accident at Fukushima Daiichi nuclear power plant on 11 March 2011, radioactive materials were released into the atmosphere resulting in environmental contamination. Following the implementation of environmental decontamination efforts, the Radiation Dose Registration Centre of the Radiation Effects Association established the radiation dose registration system for decontamination and related workers to consolidate and prevent the loss of radiation records. This article presents statistics on the radiation doses of decontamination and related workers using official records. Since approximately 10 years have passed since the accident in Fukushima, the types of work conducted in the affected restricted areas have changed over time. Therefore, changes in radiation dose for each type of work and comparisons with nuclear workers are presented.

The role of inflammatory markers and calculated osmotic pressure in the classification of febrile seizures

OBJECTIVE

Systemic inflammatory response may contribute to the onset of febrile seizures (FSs). The neutrophil-to-lymphocyte ratio (NLR) has been reported to be useful for differentiating simple and complex FSs in children with a first FS. This study aimed to determine whether easily measurable inflammatory markers were useful for distinguishing between the types of FSs in children with FSs not limited to the first FS.

PATIENTS AND METHODS

We conducted a retrospective study of children aged 6-60 months who were presented to the Atsugi City Hospital in Japan for the treatment of FSs between December 2018 and February 2020. A complex FS was defined as a seizure with multiple seizures during the same febrile illness, prolonged seizures and/or focal seizures. A simple FS was defined as a seizure without the characteristics of complex FS. We assessed complete blood count, C-reactive protein, and calculated osmotic pressure.

RESULTS

A total of 205 children with FSs (simple, 139; complex, 66) fulfilled the inclusion criteria. None of the inflammatory markers, including NLR, could predict the FS type. The median osmotic pressure was 279.0, 278.8, 283.3, and 278.3 mOsm/kg H2O for children with simple, multiple, prolonged, and focal seizures, respectively. Children with prolonged seizures had a significantly higher calculated osmotic pressure than those with simple FSs (p<0.001) and multiple seizures during the same febrile illness (p=0.004).

CONCLUSIONS

Easily measurable inflammatory markers, including NLR, were not useful for distinguishing between types of FSs in children. Large multicenter studies are needed to evaluate the association between osmotic pressure and FS.

Preoperative MRI for predicting pathological changes associated with surgical difficulty during laparoscopic cholecystectomy for acute cholecystitis

BACKGROUND

Severe inflammation with necrosis and fibrosis of the gallbladder in acute cholecystitis increases operative difficulty during laparoscopic cholecystectomy. This study aimed to assess the use of preoperative MRI in predicting pathological changes of the gallbladder associated with surgical difficulty.

METHODS

Patients who underwent both preoperative MRI and early cholecystectomy for acute cholecystitis between 2012 and 2018 were identified retrospectively. On the basis of the layered pattern of the gallbladder wall on MRI, patients were classified into three groups: high signal intensity (HSI), intermediate signal intensity (ISI), and low signal intensity (LSI). The endpoint was the presence of pathological changes of the gallbladder associated with surgical difficulty, such as necrosis, abscess formation and fibrosis.

RESULTS

Of 229 eligible patients, pathological changes associated with surgical difficulty were found in 17 (27 per cent) of 62 patients in the HSI group, 84 (85 per cent) of 99 patients in the ISI group, and 66 (97 per cent) of 68 patients in the LSI group (P < 0·001). For detecting these changes, intermediate to low signal intensity of the gallbladder wall had a sensitivity of 90 (95 per cent c.i. 84 to 94) per cent, specificity of 73 (60 to 83) per cent and accuracy of 85 (80 to 90) per cent.

CONCLUSION

Preoperative MRI predicted pathological changes associated with surgical difficulty during laparoscopic cholecystectomy for acute cholecystitis.

P107 Predictors of increased d-dimer level at follow-up period after transcatheter aortic valve implantation.Is oral anticoagulation therapy better?

Background

Recently, there are some reports that hypo-attenuated leaflet thickening (HALT) following transcatheter aortic valve implantation (TAVI) is incidentally detected by multi-slice computed tomography. It is believed that valve thrombosis causes HALT, because oral anticoagulation therapy (OAC) is effective for HALT regression. Furthermore, it is reported that d-dimer level increases in patients with HALT, and might be a key biomarker to detect HALT.

Purpose

We sought to investigate the predictors related to increased d-dimer level at 6 months after follow-up TAVI.

Methods

We enrolled 124 consecutive patients who underwent successful TAVI between 2016 and 2018. Study patients were classified into two groups according to antithrombotic therapy resume (OAC therapy or anti-platelet therapy).We set the primary endpoint as the d-dimer levels at 6 months after TAVI. To evaluate the risks of the primary endpoint, we employed a multivariable linear regression model, setting the primary endpoint as an objective variable and patient and clinical backgrounds as explanatory variables. Furthermore, we set the secondary endpoint as one-year bleeding event.

Results

The median age of patients was 83 years old (quartile 80-87). Patients who had taken OAC at 6 months follow-up after TAVI were 29.8%. The median d-dimer level at 6 months after TAVI was 1.3 (1.0-2.2) µg/ml, and OAC group had statistically lower d-dimer level at 6 months follow-up than those in non-OAC group (p = 0.020). Uni-variable liner regression model demonstrated that increased d-dimer level at follow-up had significant relationship with large effective orifice area (EOA) (p = 0.002) and low left ventricular ejection fraction (LVEF) (p = 0.048) after TAVI. Furthermore, large EOA (p = 0.003) and OAC therapy (p = 0.027) were independently associated with increased d-dimer level in multivariate analysis. Kaplan-Meier estimates revealed that there were no significant difference regarding one-year bleeding event between OAC group and non-OAC group (long-rank p = 0.167).

Conclusions

This study suggests that large EOA after TAVI is associated with increased d-dimer levels at 6 months after TAVI, and OAC therapy might have a potential to decrease d-dimer level after TAVI without increase of bleeding events.

Abstract P107 Figure: One-year bleeding event

P3693Self-expandable transcatheter aortic valve implantation is associated with frequent periprocedural stroke detected by diffusion-weighted magnetic resonance imaging -Insight from propensity score match

Background

Little evidence is available regarding the risk of peri-procedural stroke detected by diffusion-weighted magnetic resonance imaging (DW-MRI) after transcatheter aortic valve implantation (TAVI). Our purpose was to evaluate stroke risk after TAVI using DW-MRI by enrolling consecutive patients who underwent transfemoral TAVI and post-procedural DW-MRI.

Methods

We prospectively enrolled 113 consecutive patients who underwent transfemoral TAVI and post-procedural DW-MRI. We used balloon-expandable valves as first-line therapy and selected self-expandable valves only for patients with narrow sinotubular junctions or annuli. We set the primary endpoint as the number of high intensity areas (HIA) detected by DW-MRI regardless of the size of the area. To evaluate the risks of the primary endpoint, we employed a multivariable linear regression model, setting the primary endpoint as an objective variable and patient and clinical backgrounds as explanatory variables. In addition, the relationship between valve type and the number of HIAs on DW-MRI was also confirmed by the propensity score matching analysis to evaluate the robustness of the result, using a multivariable linear regression model with the protocol described in the previous manuscript. Shortly, the propensity score was calculated with a logistic regression model by setting the treatment as the response variable and baseline characteristics and procedural information that were significantly different between 2 groups (balloon expandable and self-expandable) as explanatory variables, which included age, estimated glomerular filtration rate, oversizing rate, and BAV before THV deployment.

Results

Median patient age was 84 years, and 36.3% were men. Ninety-three patients underwent balloon-expandable TAVI and 20 underwent self-expandable TAVI. Symptomatic stroke occurred in 6 (5.3%) whereas asymptomatic stroke occurred in 59 (52.2%) patients. The incidence of symptomatic and total stroke was higher in patients who underwent self-expandable TAVI than those who underwent balloon-expandable TAVI (30.0% vs 0.0%, p<0.001 and 90.0% vs 50.5%, p=0.001, respectively). A multivariable linear regression model demonstrated an increased primary endpoint when self-expandable TAVI was performed (p<0.001). The other covariates had no significant relationship to the primary endpoint. Akaike information criterion-based stepwise statistical model selection revealed that valve type was the only explanatory variable for the best predictive model. This result was also confirmed with the propensity score matching analysis (estimate, 2.359; 95% CI, 0.426–4.292; p=0.019) after adjustments of propensity score, in which 28 patients were matched (n=14 in each group).

Conclusions

Self-expandable valves were associated with increased numbers of HIA on DW-MRI after TAVI in patients with severe aortic stenosis.

P4158Marked impairment of endothelium-dependent digital vasodilatations in patients with microvascular angina compared with those with vasospastic angina

Background/Introduction

Nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH) factor are the major endothelium-derived relaxing factors. NO plays an important role in conduit arteries, while the importance of EDH factor increases as the vessel size decrease in patients with microvascular angina (MVA) compared with those with vasospastic angina (VSA) remains to be fully elucidated.

Purpose

We evaluated the roles of NO and EDH factor in conduit (brachial) arteries and resistance (digital) arteries of the patients with MVA, VSA and comorbid MVA+VSA patients.

Methods

We enrolled 39 patients who underwent diagnostic cardiac catheterization and divided them into 3 groups based on acetylcholine (ACh) provocation test, index of microcirculation resistance (IMR), and coronary flow reserve (CFR); MVA (N=9, mean age 59.9±3.5 years), VSA (N=12, mean age 61.3±1.8 years), and comorbid MVA+VSA (N=18, mean age 64.0±2.2 years). Endothelium-dependent brachial and digital vasodilatations in response to intra-arterial infusion of bradykinin (BK, 25, 50, and 100 ng/min for 2 min) were simultaneously measured by ultrasonography and peripheral arterial tonometry, respectively. Measurements were repeated after oral administration of aspirin (486 mg) and intra-arterial infusion of NG-monomethyl-L-arginine (L-NMMA, 8μmol/min for 5 min) in order to inhibit the effects of vasodilator prostaglandins and NO, respectively. Finally, endothelium-independent brachial and digital vasodilatations in response to sublingual nitroglycerin (NTG, 0.3 mg) were measured in the same manner.

Results

In the brachial artery, dose-dependent vasodilatations to BK were comparable among the 3 groups, and L-NMMA equally attenuated the responses to BK (Figure 1). Endothelium-independent brachial vasodilatation in response to NTG was also comparable among the 3 groups. Surprisingly, dose-dependent digital vasodilatations to BK were almost absent in MVA patients compared with VSA or comorbid MVA+VSA group (Figure 2). Furthermore, the digital vasodilatations were unaffected by L-NMMA in VSA group, but were significantly reduced in comorbid MVA+VSA group (VSA, 16.8±15.1% vs. MVA+VSA, −0.23±6.2%, P<0.05), suggesting reduced EDH and compensatory role of NO in the latter group. In contrast, endothelium-independent digital vasodilatation in response to NTG was comparable among the 3 groups.

The main results of this study

Conclusions

These results provide the first evidence that endothelium-dependent digital vasodilatations (both NO and EDH factor) are markedly impaired in MVA patients compared with VSA or comorbid MVA+VSA patients, whereas the responses are comparable in the brachial artery among the 3 groups, suggesting the involvement of severe endothelial dysfunction in the pathogenesis of MVA.

Quantitative analysis of mammalian chromosome by scanning transmission soft X-ray microscopy

Soft X-ray spectromicroscopy was applied to study the quantitative distribution of DNA and protein in a mammalian chromosome at the spatial resolution of 100 nm. The quantities of DNA and protein were evaluated using 1s-π* transition in the NEXAFS spectra at the nitrogen K absorption edge. DNA was not uniformly distributed in the chromosome and DNA/protein ratio was less than 0.497. The present analysis revealed the clues to identify other molecules that contribute to the absorption spectrum of the sample. The results suggested that accumulation of the absorption spectra of relevant molecules would support the refinement of the analysis.

Comparative phenology of dormant Japanese pear (Pyrus pyrifolia) flower buds: a possible cause of 'flowering disorder'

Mild winters influenced by global warming have increased the incidence of erratic flowering ('flowering disorder') in Japanese pear (Pyrus pyrifolia Nakai) trees in Japan. To discover how, when and what kind of disorder/damage occur in pear flower buds, we observed axillary flower buds of two cultivars, 'Kosui' (a mid-chill cultivar) and 'Niitaka' (a high-chill cultivar), grown at five locations. We focused on the phenology from autumn 2015 to spring 2016, when temperatures were higher than for average years, especially from September to January, and large fluctuations occurred due to El Niño. During the blooming season in the spring of 2016, both the percentage of blooming flower buds and the number of florets per flower bud decreased in trees located at lower latitudes (with lower chilling accumulation) with a more severe problem in 'Niitaka' than in 'Kosui'. As shown by forcing excised shoots, the onset and release of endodormancy occurred earlier in 'Kosui' than 'Niitaka' and occurred earlier in trees growing at higher latitudes than at lower latitudes (warmer regions). The freezing tolerance of flower buds, measured as the lethal temperature for 50% survival (LT50), was similar for the cultivars beginning in autumn and reached maximum levels, LT50 values of less than -12 °C, between late-December and mid-January in both cultivars, except for those in Kagoshima (the lowest latitude), where the maximum LT50 was only -5 °C throughout the season. We propose that warmer autumn-winter temperatures may prevent the acquisition of freezing tolerance, disturb endodormancy progression and disrupt floral organ development, thereby causing flowering disorder in pear trees. The risk of occurrence of flowering disorder in pear may be higher in high-chill cultivars than in low- or mid-chill cultivars and at lower latitudes compared with higher latitudes.

Case report: Electron microscopic evaluation of bone from a patient treated with cinacalcet hydrochloride, maxacalcitol, and alfacalcidol for hyperparathyroid bone disease with secondary hyperparathyroidism

Evaluation of bone is of great importance in chronic kidney disease patients, as these patients are at an increased risk for fractures. We treated a hemodialysis patient suffering from hyperparathyroid bone disease with cinacalcet hydrochloride and concurrent administration of maxacalcitol and alfacalcidol for a year. Hyperparathyroid bone disease is characterized by cortical thinning, increased cortical porosity, reduced trabecular bone volume, and increased hypomineralized matrix volume, and there is little information to date about the effects of treatment with cinacalcet hydrochloride on the bone fragility in patients with hyperparathyroid bone disease. In the present study, histological and backscattered electron microscopic evaluation of this combination treatment revealed an excellent improvement of both bone volume and bone morphology. This treatment improved cortical thinning, cortical porosity, and trabecular thinning. Furthermore, the treatment also reduced hypomineralized matrix volume, indicative of improved mineralization by osteocytes. We speculate that the intermittent maxacalcitol administration may have effectively stimulated the vitamin D receptors expressed on osteocytes and osteoblasts, resulting in increased mineralization. Our approach for evaluating the bone in patients with chronic kidney disease by backscattered electron microscopy is novel.

Ethanol ablation for refractory bile leakage after complex hepatectomy

BACKGROUND

Only a few reports exist on the use of ethanol ablation for posthepatectomy bile leakage. The aim of this study was to assess the value of ethanol ablation in refractory bile leakage.

METHODS

Medical records of consecutive patients who underwent a first hepatobiliary resection with bilioenteric anastomosis between 2007 and 2016 were reviewed retrospectively, with special attention to bile leakage and ethanol ablation therapy. Bile leakage was graded as A/B1/B2 according to the International Study Group of Liver Surgery definition. Absolute ethanol was injected into the target bile duct during fistulography.

RESULTS

Of the 609 study patients, 237 (38·9 per cent) had bile leakage, including grade A in 33, grade B1 in 18 and grade B2 in 186. Left trisectionectomy was more often associated with grade B2 bile leakage than other types of hepatectomy (P < 0·001). Of 186 patients with grade B2 bile leakage, 31 underwent ethanol ablation therapy. Ethanol ablation was started a median of 34 (range 15-122) days after hepatectomy. The median number of treatments was 3 (1-7), and the total amount of ethanol used was 15 (3-71) ml. Complications related to ethanol ablation included transient fever (27 patients) and mild pain (13). Following ethanol ablation, bile leakage resolved in all patients and drains were removed. The median interval between the first ablation and drain removal was 28 (1-154) days.

CONCLUSION

Ethanol ablation is safe and effective, and may be a treatment option for refractory bile leakage.

Genetic survey of alveolar and cystic echinococcoses in Romania: first molecular evidence of Echinococcus multilocularis in humans in the country

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are considered as one of the most important zoonotic diseases in Romania, where they are subject to mandatory reporting. To obtain more knowledge about the genetic diversity of Echinococcus causative agents of these diseases, 11 isolates from humans and ungulate intermediate hosts from the two regions of Romania were genotyped using mitochondrial markers. In clinical samples of five patients from north-eastern Romania (Iasi, Botosani, Vaslui counties), Echinococcus multilocularis was identified as causal agent by cox1 sequence analysis. To the best of our knowledge this finding presents the first molecular evidence of E. multilocularis in humans from Romania. Only two cases of AE in patients were previously documented in the country by serological methods. In our four patients the most widespread European variant E5 of E. multilocularis was recorded, whereas in isolate from Vaslui county three nucleotide substitutions were detected as compared to the most related E5 haplotype. One of these mutations (411T/G) matched N1 and N2 haplotypes described previously from North America. In six CE samples retrieved from western Romania (Caras-Severin and Timis counties), two human isolates were diagnosed as Echinococcus canadensis G7, one as E. granulosus s.s. G1 and one as E. granulosus s.s. G3 using atp6 and rrnS sequencing. In ungulates, the cattle isolate was allocated to E. granulosus s.s. G1 and pig isolate to E. canadensis G7. The two G7 findings in humans reinforced the recent view that G7 was underestimated as compared to the E. granulosus s.s. regarding human CE threat that can be further employed for identifying sources of infections and establishing suitable preventive measures.

Uncertainty in the response of terrestrial carbon sink to environmental drivers undermines carbon-climate feedback predictions

Terrestrial ecosystems play a vital role in regulating the accumulation of carbon (C) in the atmosphere. Understanding the factors controlling land C uptake is critical for reducing uncertainties in projections of future climate. The relative importance of changing climate, rising atmospheric CO2, and other factors, however, remains unclear despite decades of research. Here, we use an ensemble of land models to show that models disagree on the primary driver of cumulative C uptake for 85% of vegetated land area. Disagreement is largest in model sensitivity to rising atmospheric CO2 which shows almost twice the variability in cumulative land uptake since 1901 (1 s.d. of 212.8 PgC vs. 138.5 PgC, respectively). We find that variability in CO2 and temperature sensitivity is attributable, in part, to their compensatory effects on C uptake, whereby comparable estimates of C uptake can arise by invoking different sensitivities to key environmental conditions. Conversely, divergent estimates of C uptake can occur despite being based on the same environmental sensitivities. Together, these findings imply an important limitation to the predictability of C cycling and climate under unprecedented environmental conditions. We suggest that the carbon modeling community prioritize a probabilistic multi-model approach to generate more robust C cycle projections.

Physiological exercise loading suppresses post-traumatic osteoarthritis progression via an increase in bone morphogenetic proteins expression in an experimental rat knee model

OBJECTIVE

To evaluate the dose-response relationship of exercise loading in the cartilage-subchondral bone (SB) unit in surgically-induced post-traumatic osteoarthritis (PTOA) of the knee.

DESIGN

Destabilized medial meniscus (DMM) surgery was performed on the right knee of 12-week-old male Wistar rats, and sham surgery was performed on the contralateral knee. Four weeks after the surgery, the animals were subjected to moderate (12 m/min) or intense (21 m/min) treadmill exercises for 30 min/day, 5 days/week for 4 weeks. PTOA development in articular cartilage and SB was examined using histological and immunohistochemical analyses, micro-computed tomography (micro-CT) analysis, and biomechanical testing at 8 weeks after surgery. Gremlin-1 was injected to determine the role of bone morphogenetic protein (BMP) signaling on PTOA development following moderate exercise.

RESULTS

Moderate exercise increased BMP-2, BMP-4, BMP-6, BMP receptor 2, pSmad-5, and inhibitor of DNA binding protein-1 expression in the superficial zone chondrocytes and suppressed cartilage degeneration, osteophyte growth, SB damage, and osteoclast-mediated SB resorption. However, intense exercise had little effect on BMP expression and even caused progression of these osteoarthritis (OA) changes. Gremlin-1 injection following moderate exercise caused progression of the PTOA development down to the level of the non-exercise DMM-operated knee.

CONCLUSIONS

Exercise regulated cartilage-SB PTOA development in DMM-operated knees in a dose-dependent manner. Our findings shed light on the important role of BMP expression in superficial zone chondrocytes in attenuation of PTOA development following physiological exercise loading. Further studies to support a mechanism by which BMPs would be beneficial in preventing PTOA progression are warranted.

Gastrointestinal helminths and Taenia spp. in parenteral tissues of free-roaming pigs (Sus scrofa indicus) from hilltribe village at the western border of Thailand

A serological survey of pig cysticercosis was conducted in a hill-tribe village at Thai-Myanmar border, Tak province of Thailand in 2012. Sixteen backyard pigs were examined for pig cysticercosis and gastrointestinal helminth infection. In addition to cysticerci of Taenia solium and Taenia hydatigena found outside the gut, nine other helminth species were found in guts: Echinostoma malayanum, Pseudanoplocephala crawfordi, Ascarops dentata, Physocephalus sexalatus, Gnathostoma doloresi, Ascaris suum, Globocephalus sp., Oesophagostomum dentatum and Bourgelatia diducta. The study presents a report for the first time of adult tapeworm, P. crawfordi infection in pigs from Thailand. For medical importance, E. malayanum, P. crawfordi, G. doloresi and A. suum have been confirmed as potentially zoonotic helminths and pigs may act as one of the reservoir hosts for human helminthiases. Pigs of both gender and all ages appeared to be exposed to the parasites equally and did not show any significant difference to these helminth species in richness and total intensity.

Accelerated anaerobic release of K, Mg and P from surplus activated sludge for element recovery and struvite formation inhibition

Accelerated release of potassium (K), magnesium (Mg) and phosphorus (P) from surplus activated sludge (SAS) was investigated to develop a new system for the recovery of the elements. Anaerobic cultivation of SAS during 24 h released 78% of K and about 50% of Mg and P from SAS more effectively compared to aerobic cultivation (K: 40%, Mg: 15%, P: 15%). Furthermore, the addition of sodium acetate as an organic carbon source remarkably accelerated the release of K, Mg and P from SAS under anaerobic condition. However, no increase in the maximum release efficiencies was observed. The elements released from SAS could be transferred to separate liquid with the existing mechanical thickener and be recovered as MgKPO₄ by some additional process. Furthermore, the removal of the elements from SAS would inhibit the formation of struvite causing the blockage of sludge transport pipe after anaerobic digestion process of thickened sludge.

Abstract P2-01-20: The non-invasive treatment for sentinel lymph node metastasis by photodynamic therapy using a verteporfin solubilized phospholipid polymer aggregate

Introduction:

Sentinel lymph node biopsy (SLNB) has become a standard procedure for axillary lymph node evaluation in clinically node-negative breast cancer patients. Recent trial suggested that patients with 1or 2 sentinel lymph nodes (SLNs) involvement could be treated with SLNB alone.

Although SLNB is much less invasive procedure comparing with axillary lymph node dissection (ALND), it is still associated with complications such as lymph edema, numbness and pain.

Photodynamic therapy (PDT) against cancer is a non-invasive optical therapeutic method in which the topical or systemic delivery of photosensitizing drugs is followed by its subsequent activation with broadband red light.

In this study, the usefulness of PDT for treating SLN metastasis was evaluated in murine model.

Materials and Methods:

Verteporfin, a hydrophobic photosensitizer (PS) forms a soluble conjugate in aqueous medium with a water-soluble and amphiphilic PMB polymer as a solubilizer. The PMB forms stable and well-dispersed molecular aggregate when its concentration is over 1.0 mg/mL based on the hydrophobic interactions among polymer chains. The verteporfin can form conjugate (PMB-vertepoffin) with hydrophobic domain in the PMB aggregate. The PMB-verteporfin was injected at dorsum manus of BALB/c nude mice. The concentrations of verteporfin in tissues were determined by measuring the fluorescence emitted at 700 nm (with excitation at 430 nm). To develop a murine SLN metastasis model, 5 x 105 human epidermoid carcinoma A431 cells with stable expression of GFP were injected to the forearm of BALB/c nude mice. Seven days after inoculation of cancer cells, 20 μL of PMB-verteporfin was injected at dorsum manus of BALB/c nude mice and 75 J of light energy was delivered using a 640 nm diode laser for a total treatment time of 1 min. Fifty-three mice were randomly assigned to the combination of PMB-verteporfin injection and light exposure (A), light exposure alone (B), PMB-verteporfin injection alone (C), and no treatment (D) groups. Ten days after PDT, brachial lymph nodes, which were considered as SLNs were harvested and evaluated by stereoscopic fluorescence microscope. And, DNA was extracted from harvested lymph node. Human Alu family sequence was detected by 7300 Real Time PCR system (Applied Biosystems, Carlsbad CA USA) to estimate metastatic volume.

Results:

The concentration of verteporfin in SLN was siginificantly higher than other organs including lung, liver, kidney and brachial skin.

The group A significantly reduced the SLN metastasis (13%) comparing with , group B (57%), group C (46%) and group D (52%).

The Ct value in a PCR of the combination of group A (Ct=29.17) significantly reduced the SLN metastasis comparing with group B (Ct=22.45, p=0.018), group C (Ct=25.58, p=0.018) and group D (Ct=25.54, p=0.005).

Conclusions:

These data suggested that PDT using PMB as a nanotransporter of verteporfin could be a minimally invasive treatment of SLN metastasis in breast cancer, and represent a potential alternative procedure to SLNB.

Citation Format: Shimada K, Matsuda S, Jinno H, Konno T, Ito A, Arai T, Ishihara K, Kitagawa Y. The non-invasive treatment for sentinel lymph node metastasis by photodynamic therapy using a verteporfin solubilized phospholipid polymer aggregate [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-01-20.

Polybacterial aetiology and outcomes in patients with community-acquired pneumonia

SETTING

Community-acquired pneumonia (CAP) is a common cause of morbidity and mortality worldwide. While interactions among bacterial pathogens in the respiratory tract have been studied, the impact of polybacterial aetiology on mortality has not been fully elucidated.

OBJECTIVE

To investigate the impact of polybacterial aetiology on mortality, prevalence, microbial patterns and clinical characteristics among CAP patients.

DESIGN

Retrospective data analysis.

RESULTS

Bacterial aetiology was established in 711 (46.0%) of 1544 enrolled hospitalised CAP patients. Of these, polybacterial aetiology was identified in 89 (12.5%): Streptococcus pneumoniae was the most frequently identified pathogen (n = 55, 61.8%). The most prevalent microbial combination was S. pneumoniae and Haemophilus influenzae (n = 19, 21.3%). Alcoholism and lack of previous antibiotic therapy were independent predictors of polybacterial aetiology. The proportion of patients with severe pneumonia was significantly higher in the polybacterial aetiology group than in the monobacterial group. Multivariate analysis showed that polybacterial aetiology was a predictor of 30-day mortality (OR 2.14, 95%CI 1.07-4.24, P = 0.030), independently of severe pneumonia status, pneumonia severity index, chronic obstructive pulmonary disease and inappropriate empirical therapy.

CONCLUSION

Polybacterial CAP tends to advance in severity, and indicates adverse outcomes.

Exercise intervention increases expression of bone morphogenetic proteins and prevents the progression of cartilage-subchondral bone lesions in a post-traumatic rat knee model

OBJECTIVE

This study aimed to determine whether treadmill walking (TW) prevents the progression of post-traumatic osteoarthritic changes in cartilage-subchondral bone unit, and whether the exercise timing changes the exercise efficacy in destabilized medial meniscus (DMM) rat knees.

DESIGN

Twelve-week-old male Wistar rats underwent DMM surgery on their right knees and sham surgery on their left knees and were assigned to either the sedentary (n = 10) or walking (n = 24) groups. The rats in the walking group were subjected to TW from day 2 through 4 weeks, from 4 through 8 weeks, or from day 2 through 8 weeks (n = 8 per group). Osteoarthritic changes of cartilage and subchondral bone were assessed with micro-computed tomography, histology, and immunohistochemistry 8 weeks after surgery.

RESULTS

TW prevented the progression of cartilage and subchondral bone lesions induced by the DMM, and increased bone morphogenetic protein (BMP)-2 and -6 expressions in superficial zone chondrocytes and bone-lining cells including osteoblasts. Furthermore, the TW-induced increase in BMPs varied with the exercise timing. Beginning TW 4 weeks after DMM surgery was the best option for increasing BMPs, coinciding with the most robust prevention of osteoarthritic changes.

CONCLUSIONS

TW increased the expression of BMPs and prevented the progression of cartilage-subchondral bone lesions in rat knees with a DMM. Selective exercise timing may be a key factor in the development of an exercise regimen for preventing the progression of post-traumatic osteoarthritis (PTOA). Furthermore, exercise may have favorable effects even after the PTOA has been developed.

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.

Decreased expression of Met during differentiation in rat lung

Organ-specific stem cells play key roles in maintaining the epithelial cell layers of lung. Bronchioalveolar stem cells (BASCs) are distal lung epithelial stem cells of adult mice. Alveolar type 2 (AT2) cells have important functions and serve as progenitor cells of alveolar type 1 (AT1) cells to repair the epithelium when they are injured. Hepatocyte growth factor (HGF) elicits mitogenic, morphogenic, and anti-apoptotic effects on lung epithelial cells through tyrosine phosphorylation of Met receptor, and thus is recognized as a pulmotrophic factor. To understand which cells HGF targets in lung, we identified the cells expressing Met by immunofluorescence assay. Met was strongly expressed in BASCs, which expressed an AT2 cell marker, pro-SP-C, and a club cell marker, CCSP. In alveoli, we found higher expression of Met in primary AT2 than in AT1 cells, which was confirmed using primary AT2 cells. We further examined the mitogenic activity of HGF in AT2-cell-derived alveolar-like cysts (ALCs) in 3D culture. Multicellular ALCs expressed Met, and HGF enhanced the ALC production. Taking these findings together, BASCs could also be an important target for HGF, and HGF-Met signaling could function more potent on cells that have greater multipotency in adult lung.

Subchondral plate porosity colocalizes with the point of mechanical load during ambulation in a rat knee model of post-traumatic osteoarthritis

OBJECTIVE

This study investigated the association between spatiotemporal cartilage-subchondral bone plate alterations and mechanical load during ambulation in an experimental rat model of destabilized medial meniscus (DMM).

DESIGN

Twelve-week-old Wistar rats (n = 38) underwent DMM surgery on the right knee and sham surgery on the left knee. At 2 and 4 weeks after surgery, subchondral bone changes were evaluated via micro-computed tomography with various knee flexion angles to simulate weight-bearing during rat ambulation under a 3-dimensional motion capture apparatus. Additionally, the biomechanical properties, histology, and ultrastructure of the medial tibia and femoral condyle were evaluated.

RESULTS

Focal subchondral bone plate perforations were confirmed in the medial tibia within 2 weeks after surgery and were aggravated rapidly 2 weeks later. This subchondral plate porosity colocalized with articular cartilage lesions as confirmed by histology and scanning electron microscopy, and coincided with the likely point of contact between the posterior femoral condyle and tibial plateau during ambulation. Biomechanical properties were confirmed at the medial tibia, at which stiffness was reduced to approximately half that of the sham-operated knee at 4 weeks after surgery.

CONCLUSIONS

Cartilage-subchondral bone plate alterations localized in the region of the point of mechanical load during ambulation in DMM-operated knees, at which the mechanical integrity of cartilage was impaired. These results indicate that DMM-induced increases in mechanical load play an important role in the pathogenesis of early post-traumatic osteoarthritis (OA), and it might accelerate the development of the disease via cartilage-subchondral bone plate crosstalk through increased subchondral plate perforations.

Talaporfin sodium binding and photocytotoxicity of photosensitization reaction on myocardial cell under various albumin concentrations and temperature

To understand the efficiency change of the extracellular photosensitization reaction by the external factor in myocardium interstitial space, we studied the efficiency change of the extracellular photosensitization reaction caused by talaporfin sodium binding with serum proteins under various serum proteins concentrations and temperature conditions. Talaporfin sodium Q band absorbance was measured with various albumin concentrations and the cell survival rate was measured by WST assay in the same conditions. The talaporfin sodium binding ratio with albumin, high-density lipoprotein, and low-density lipoprotein were measured by talaporfin sodium absorbance measurement after the ultrafiltration. The albumin concentration affects the photocytotoxicity strongly when the albumin concentration was over 2.1 mg/ml in the case of the extracellular photosensitization reaction. It would be useful to measure the peak wavelength in Q band absorbance was suggested to know the albumin concentration and the photocytotoxicity efficiency to realize the safety treatment. The binding ratios with high-density lipoprotein and low-density lipoprotein were decreased with the solution temperature rise from 17°C to 37 °C and the photocytotoxicity was increased with temperature rise from 17°C to 37°C involving this binding ratio change. It would be important to maintain the target organ temperature during the photosensitization reaction to keep the photosensitization reaction efficiency.

An automated method for detecting architectural distortions on mammograms using direction analysis of linear structures

Architectural distortion is one of the most important findings when evaluating mammograms for breast cancer. Abnormal breast architecture is characterized by the presence of spicules, which are distorted mammary structures that are not accompanied by an increased density or mass. We have been developing an automated method for detecting spiculated architectural distortions by analyzing linear structures extracted by normal curvature. However, some structures that are possibly related to distorted areas are not extracted using this method. The purpose of this study was to develop a new automated method for direction analysis of linear structures to improve detection performance in mammography. The direction of linear structures in each region of interest (ROI) was first determined using a direction filter and a background filter that can define one of eight directions (0°, 22.5°, 45°, 67.5°, 90°, 112.5°, 135°, and 157.5°). The concentration and isotropic indexes were calculated using the determined direction of the linear structures in order to extract the candidate areas. Discriminant analysis was performed to eliminate false positives results. Our database consisted of 168 abnormal images containing 174 distorted areas and 580 normal images. The sensitivity of the new method was 81%. There were 2.6 and 4.2 false positives per image using the new and previous methods, respectively. These findings show that our new method is effective for detecting spiculated architectural distortions.

Lower expression of activating transcription factors 3 and 4 correlates with shorter progression-free survival in multiple myeloma patients receiving bortezomib plus dexamethasone therapy

Bortezomib (BTZ), a proteasome inhibitor, is widely used in the treatment of multiple myeloma (MM), but a fraction of patients respond poorly to this agent. To identify factors predicting the duration of progression-free survival (PFS) of MM patients on BTZ treatment, the expression of proteasome and endoplasmic reticulum (ER) stress-related genes was quantified in primary samples from patients receiving a combination of BTZ and dexamethasone (BD). Fifty-six MM patients were stratified into a group with PFS<6 months (n=33) and a second group with PFS⩾6 months (n=23). Of the 15 genes analyzed, the expression of activating transcription factor 3 (ATF3) and ATF4 was significantly lower in patients with shorter PFS (P=0.0157 and P=0.0085, respectively). Chromatin immunoprecipitation analysis showed that these ATFs bind each other and transactivate genes encoding the pro-apoptotic transcription factors, CHOP and Noxa, which promote ER stress-associated apoptosis. When either ATF3 or ATF4 expression was silenced, MM cells partially lost sensitivity to BTZ treatment. This was accompanied by lower levels of Noxa, CHOP and DR5. Thus low basal expression of ATF3 and ATF4 may attenuate BTZ-induced apoptosis. Hence, ATF3 and ATF4 could potentially be used as biomarkers to predict efficacy of BD therapy in patients with MM.