Electrocatalytic synthesis of ammonia by surface proton hopping

Highly efficient ammonia synthesis at a low temperature is desirable for future energy and material sources. We accomplished efficient electrocatalytic low-temperature ammonia synthesis with the highest yield ever reported. The maximum ammonia synthesis rate was 30 099 μmol gcat-1 h-1 over a 9.9 wt% Cs/5.0 wt% Ru/SrZrO3 catalyst, which is a very high rate. Proton hopping on the surface of the heterogeneous catalyst played an important role in the reaction, revealed by in situ IR measurements. Hopping protons activate N2 even at low temperatures, and they moderate the harsh reaction condition requirements. Application of an electric field to the catalyst resulted in a drastic decrease in the apparent activation energy from 121 kJ mol-1 to 37 kJ mol-1. N2 dissociative adsorption is markedly promoted by the application of the electric field, as evidenced by DFT calculations. The process described herein opens the door for small-scale, on-demand ammonia synthesis.

Surveys of Food Intake Just after the Nuclear Accident at the Fukushima Daiichi Nuclear Power Station

As a result of the nuclear accident at the Fukushima Daiichi nuclear power station (FDNPS) after the Great East Japan Earthquake on March 11, 2011, volatile radionuclides including iodine-131 were released into the environment and contaminated open-field vegetables, raw milk, tap water, etc. It is important for the health care of residents to correctly comprehend the level of their exposure to radioactive substances released following the accident. However, an evaluation of the internal exposure doses of residents of Fukushima Prefecture as a result of the ingestion of foods, which is indicated in the report issued by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR)1 is based on a number of assumptions. For instance, the estimation assumes that foods were ingested as usual, without regard to the places to which residents were evacuated after the accident, the places where food shipment restrictions were imposed, and so forth. The present report aims to improve the accuracy of estimation of the amount of food actually ingested at evacuation areas, in order to reduce as much as possible the level of uncertainty in conventional values estimated directly after the accident, which were in fact values based on conservative assumptions. More concretely, as basic source material to more accurately estimate internal exposure doses from food ingestion, various patterns of evacuation and dietary habits at the time of the accident of the residents of 13 municipalities in Fukushima Prefecture who were evacuated during the period from directly after the accident of March 11, 2011 until the end of March are clarified in this report. From survey results, most of the food that evacuees took immediately after the accident was confirmed to have been sourced from either stockpiles prepared before the accident, or relief supplies from outside of the affected areas. The restriction orders of food supplies such as contaminated vegetables and milk, and tap water intake were implemented within several days after the major release of radionuclides on March 15, 2011. In addition, collapse in supply chains, i.e., damage to distribution facilities, lack of transportation vehicles or electricity, and the closure of retail stores, contributed to a situation where food or supplies contaminated with iodine -131 were not consumed in large quantities in general, even before the food restriction order. Since people consumed tap water and water from other sources before the implementation of restriction orders in affected areas, we surveyed the status of water as a potential route of internal exposure.

Evaluation of the effectiveness of the potent bis-quaternary ammonium compound, 4,4'-(α,ω-hexametylenedithio) bis (1-octylpyridinium bromide) (4DTBP-6,8) on Pseudomonas aeruginosa

AIMS

Quaternary ammonium compounds (QACs), including benzalkonium chloride (BAC) and cetylpyridinium chloride (CPC) are cationic surfactants and have been used widely as general disinfectants in the medical field due to their strong antibacterial effects and low cytotoxicity to human cells. 4,4'-(α,ω-hexametylenedithio) bis (1-octylpyridinium bromide) (4DTBP-6,8) is one of the potent bis-QACs synthesized to improve the antimicrobial activities of mono-QACs such as BAC. This study aimed to assess the effectiveness of 4DTBP-6,8 against Pseudomonas aeruginosa, a prevalent hospital pathogen.

METHODS AND RESULTS

The minimum inhibitory concentrations of 4DTBP-6,8, CPC and BAC against P. aeruginosa were measured. 4DTBP-6,8 exhibited strong antibacterial activity. We assessed the bactericidal effects of QACs against P. aeruginosa under certain conditions and their cytotoxicities in human epithelial cells using lactate dehydrogenase (LDH) release. 4DTBP-6,8 exerted excellent bactericidal effects against high concentrations of bacteria, biofilm cells and even in the presence of contaminated proteins. Cellular LDH was not released by the treatment with 4DTBP-6,8.

CONCLUSIONS

4DTBP-6,8 exhibited the strongest bactericidal activity against P. aeruginosa among the three QACs tested without any cytotoxicity.

SIGNIFICANCE AND IMPACT OF THE STUDY

The potent bis-QAC, 4DTBP-6,8 has the potential to be an effective disinfectant in preventing hospital infections caused by P. aeruginosa.

Novel reuterin-related compounds suppress odour by periodontopathic bacteria

OBJECTIVE

Halitosis is caused by volatile sulphur compounds including methyl mercaptan (CH₃ SH) in the oral cavity and is a serious problem that limits interpersonal social communication. The aim of study was to evaluate the effects of reuterin-related compounds (RRCs) on halitosis-related periodontopathic bacteria in vitro.

MATERIALS AND METHODS

RRC-01, RRC-02 and RRC-03 (32 and 64 μg ml^-1 ) in culture media containing Fusobacterium nucleatum JCM8523 and Porphyromonas gingivalis ATCC33277 were used. The effects of RRCs on CH₃ SH production and detectable odour by F. nucleatum and P. gingivalis were examined by CH₃ SH production assay and organoleptic test, respectively. The number of bacterial cells was also measured using an ATP assay. In P. gingivalis treated with RRCs, the expression of mgl gene, which is responsible for CH₃ SH production, was examined by qRT-PCR.

RESULTS

CH₃ SH production and the score of detectable odour from F. nucleatum and P. gingivalis culture media containing RRCs were significantly lower than that without RRCs (P < 0.05). The expression of mgl gene in P. gingivalis was significantly downregulated by RRC-01 (P < 0.01), but not by RRC-02 or RRC-03.

CONCLUSIONS

RRCs are potent oral care products for preventing halitosis via reducing CH₃ SH production.

Polymorphisms in PTCH1 Affect the Risk of Ameloblastoma

Ameloblastoma is the most common odontogenic tumor, but the genetic nature of the changes in the tumor cells has been unclear. Mutations of CTNNB1 or PTCH1 are observed in many human tumors. Both CTNNB1 and PTCH1 are important in tooth development and are expressed in ameloblastoma. The aim of this study was to investigate whether genetic alterations of CTNNB1 and PTCH1 are present in ameloblastoma. We investigated 14 cases of ameloblastoma. The polymorphisms found in the ameloblastoma patients were further examined in a subsequent case-control study. We found a CTNNB1 mutation in one case of plexiform-type ameloblastoma. CGG triplet repeat-number polymorphism (CGG7/CGG8) in the 5′-untranslated region of PTCH1 was observed. The proportion of CGG8 alleles was significantly higher in the ameloblastoma group. The results of this study indicate a possible relationship between the CGG8 allele in PTCH1 and the risk for ameloblastoma.

Antiviral Activity and Molecular Geometry of Some New Symmetrical Tris(aminoalkyl)amine Derivatives

We report the preparation of new tripodal receptor-type C₃- and C_S-symmetrical molecules constructed on a tris(2-aminoethyl)amine (TAEA) template. Both the anti-herpes simplex virus type 1 (anti-HSV-1) activity and cytotoxic activity of synthesized receptor-type derivatives were evaluated in order to find a characteristic structural feature for these bioactivities of compounds. Among the compounds of synthesized symmetrical TAEA-related derivatives, compound 13k showed high anti-HSV-1 activity (50% effective concentration (EC₅₀)=16.7 µM) and low cytotoxicity (50% cytotoxic concentration (CC₅₀)=>200 µM). The presence of a hydrogen bond donor proton in the molecule is thought to be an important structural factor for expressing potential anti-HSV-1 activities.

An autopsied case of neuromyelitis optica with a large cavitary cerebral lesion

We report a case of neuromyelitis optica (NMO) with a large cerebral lesion. The patient had an episode of fever and consciousness disturbance with a tumefactive frontal white matter lesion at age 43, and then repeated bilateral optic neuritis and transverse myelitis until she died at age 63. Histopathological examinations revealed that marked tissue destruction, cavities and inflammatory changes typical of NMO were seen in the cerebrum as well as the optic nerves and spinal cord. This is the first autopsied case of NMO with a tumefactive cerebral lesion that later became cavitary.

Abstract P4-09-26: The difference between metachronous and synchronous bilateral breast cancer in terms of clinical features and biology

Introduction

The recent diagnostic modality such as MRI can diagnose a tiny breast lesion even in healthy contralateral breasts. Recently, the rate of contralateral prophylactic mastectomy (CPM) is on the rise in the United States. In Japan, the CPM has been started for selected patients with a high risk. In this study, we divided bilateral breast cancers into the synchronous and the metachronous group and then compared the clinical features and biology.

Patients and Methods

Out of 216 bilateral breast cancer patients who underwent surgery between 1995 and March 2015, there were 101 synchronous breast cancer cases and 115 metachronous breast cancer cases (interval to the second tumor &gt; 1 year). The items examined were age, tumor size, lymph nodal status, histological type, and biological markers (ER, PgR, HER2, p53 and Ki-67 index values) in the cases with paired data.

Results

1. The incidence of metachronous tumors was relatively stable at 2.1–2.7% throughout the period. On the other hand, the incidence of synchronous tumors has increased to 4.4% in the most recent 5-year period and the median interval was 7.1 years.

2. There was no difference in the tumor size of both tumors in the synchronous group, but the second tumor was significantly smaller than the first tumor in the metachronous group (2.2cm to 1.7cm). The node negative rates showed no difference between two groups.

3. The cases with DCIS were seen in 20% and 25% of the synchronous group and 12% and 16% of the metachronous group. Most of the patients (94.3%) with invasive cancer received systemic adjuvant therapy in the metachronous group.

4. The ER positive rates of both tumors were 87.1% and 88.1% in the synchronous group and 71.6% and 68.4% in the metachronous group, respectively. The concordance rates were higher in the synchronous group (p=0.02). Moreover, there was a significant difference in ER positive rates between the two groups (p=0.01) and the ER negative tumors were more frequent in the second tumor of the metachronous group. The PgR negative tumors increased in the second tumor of metachronous cases. The shorter the interval (&lt; 5years), the more the ER positive rate decreased (p=0.002). However, the longer interval did not correlate with the change of receptor status.

5. The Ki-67 index values significantly increased in the second tumor of the metachronous group, especially in the cases with a shorter interval. However, there was no difference in the synchronous group. The p53 overexpression rates significantly increased in the cases with a shorter interval.

6. The postoperative prognosis for the first tumor did not differ in both groups.

Conclusion

The incidence of synchronous bilateral breast cancer cases have increased but have remained relatively stable in the metachronous group. The concordance rates of the ER, PgR, Ki-67 and p53 status were higher in the synchronous group but the cases with negative ER, negative PgR, higher Ki-67 values and positive p53 increased in the second tumor of the metachronous group. These findings suggest that adjuvant systemic therapy played a important role in the treatment of bilateral breast cancer but the secondary tumor was more aggressive in the metachronous cases.

Citation Format: Arima N, Nishimura R, Osako T, Nishiyama Y, Fujisue M, Okumura Y, Murakami K, Toyozumi Y. The difference between metachronous and synchronous bilateral breast cancer in terms of clinical features and biology. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-09-26.

Correction of coronal alignment correlates with reconstruction of joint height in unicompartmental knee arthroplasty

OBJECTIVES

Because there have been no standard methods to determine pre-operatively the thickness of resection of the proximal tibia in unicompartmental knee arthroplasty (UKA), information about the relationship between the change of limb alignment and the joint line elevation would be useful for pre-operative planning. The purpose of this study was to clarify the correlation between the change of limb alignment and the change of joint line height at the medial compartment after UKA.

METHODS

A consecutive series of 42 medial UKAs was reviewed retrospectively. These patients were assessed radiographically both pre- and post-operatively with standing anteroposterior radiographs. The thickness of bone resection at the proximal tibia and the distal femur was measured radiographically. The relationship between the change of femorotibial angle (δFTA) and the change of joint line height, was analysed.

RESULTS

The mean pre- and post-operative FTA was 180.5° (172.2° to 184.8°) and 175.0° (168.5° to 178.9°), respectively. The mean δFTA was 5.5° (2.3° to 10.1°). The joint line elevation of the tibia (JLET) was 4.4 mm (2.1 to 7.8). The δFTA was correlated with the JLET (correlation coefficient 0.494, p = 0.0009).

CONCLUSIONS

This study indicated that there is a significant correlation between the change of limb alignment and joint line elevation. This observation suggests that it is possible to know the requirement of elevation of the joint line to obtain the desired correction of limb alignment, and to predict the requirement of bone resection of the proximal tibia pre-operatively. Cite this article: Bone Joint Res 2015;4:128-133.