On-site analysis for nitrogen oxides using a newly developed portable flow injection analyzer

A new portable flow injection system was developed for on-site chemical analysis, which allows the rapid analysis of aqueous samples at sampling sites. The system comprises a newly designed double-plunger micro pump, a six-way sample injector, a reaction coil in a thermostated compartment and a detector. All of these units are connected with 0.5 mmi.d. PTFE tubing. A visible detector is assembled using a maximum wavelength of 525 nm of a light-emitting diode (LED) and 540 nm of an interference filter. The system is of the one-box type, whose dimensions are 160(W) x 160(H) x 320(D) mm, and is easy to carry to the analysis site; the weight is 8 kg. A thermostated compartment is incorporated into the proposed system in order to be used outdoors, where temperatures are changeable. The system can workwith DC 12Vas well as AC 100V; therefore, a car battery or a portable battery can be used as the power source. The analytical data can be memorized in IC cards or a note-book personal computer connected with a RS232C cable. Furthermore, software on the market can be easily used. By using the proposed system, the on-site determination of nitrogen oxides, such as nitrate and nitrite, could be carried out. Calibration graphs for nitrate and nitrite ions were linear over ranges of 0 to 1.0ppm and 0 to 100ppb ofN-NOs and N-NO2 with good precision; the sampling rate was 40~50 samples per hour. The detection limit for N-NO3 and N-NO2 was 0.5 ppb. By using the proposed system, the on-site determination of nitrate and nitrite in river water samples was carried out. The relative standard deviations of ten injections were 0.65% for nitrate and 0.15% for nitrite. Furthermore, nitrate and nitrite in biological samples as a metabolic products of nitric oxide, which have attracted a lot of attension as a messenger of diverse physiological processes, were also determined on-site with high sensitivity. By using a car battery as a power source, the proposed system worked continuously. In addition, it worked for about 5 hours continuously with a portable battery.試料採取現場での迅速な分析，すなわちオンサイト分析のための新しいポータブルフローインジェクション分析計の開発を行った・このFIA装置では，160×160誉320（mm）の箱の中にダブルプランジ ャーマイクロポンプ，試料注入語検出器及び反応恒温槽を組み入れ，重量8kgと小型・軽量化を達成し，持ち運び容易な分析計とした．特に，525nmの発光ダイオード（LED）を光源とする新規検出 器を開発することにより，小型，省電力化が可能となった．温度変化の大きな屋外での測定に耐えられるように，反応恒温槽も装備した．本FIA装置は交流100Vでのほか，直流12Vでも稼働し，カーバ ッテリーや市販のポータブルバッテリーを電源とするオンサイト分析に対応できるよう設計した．カーバッテリーを電源とした場合は長時間の連続運転が可能である．測定データはメモリーカードや RS232Cによりノート型パーソナルコンピュータへの通信も可能で，更に市販の表計算ソフトを利用してデータ処理が可能である．本装置を窒素酸化物のオンサイト分析に応用した．硝酸，亜硝酸イオン標準液による検量線は，0～1・Oppm，0～100ppbの範囲で直線性，再現性共に良好で，1時間当たり40～50試料の分析が可能であった・検出限界（5／Ⅳ＝3）は硝酸，亜硝酸態窒素として0．5ppbと通常のFIAシステムを用いる場合と全く変わらない優れた性能を有することが分かった．河川水中の硝酸，亜硝酸イオンのオンサイト分析では10回の繰り返し測定における相対標準偏差は0．65％及び0．15％と良好な結果が得られた．また，血清中の一酸化窒素（NO）の酸化代謝物としての硝酸，亜硝酸イオン濃度のオンサイト分析を行い，良好な結果を得た．本研究で検討したポータブルバッテリーでは1回の充電で5時間の連続運転が可能であった

Spontaneous esophageal perforation within a hiatal hernia : A case report

Introduction: Spontaneous esophageal perforation, also commonly referred to as Boerhaave's syndrome, is one of the most lethal diseases causing an acute abdomen. Though rare, emergent surgical intervention is often required and management can be various based upon the site of the perforation. This literature has been written in line with the SCARE criteria (Agha et al., 2020) [1]. Presentation of case: A 76-year-old man presented with acute abdominal pain. Computed tomography (CT) revealed and an emergent esophagogastroduodenoscopy (EGD) was performed carefully, which revealed a 7 cm all-layer esophageal laceration in the left lower esophageal wall. In our case, a hiatal hernia was protruding into the mediastinum, and the perforation site was inside of it, but there was no invasion into the thoracic cavity, thus a transabdominal approach was performed without thoracotomy. Discussion: This type of esophageal perforation within a hiatal hernia is quite rare and provides a unique clinical challenge. In addition, A review reported the average length of spontaneous esophageal perforation to be around 2 cm while our case had a perforation with a length of 7 cm. We chose the combination of the simple suture with omental buttress and wide drainage, but a complete fundoplication was impossible due to its large size of perforation. Conclusion: We chose the open abdominal approach because the case had high inflammation, a hiatal hernia and possibility of retro-gastric perforation. However, MIS should have been considered first if a situation or human resources allow it

Schwannoma resembling metastatic lymph node

In this report, we describe a rare case of vagus nerve schwannoma associated with esophageal cancer. A 70-year-old man visited our hospital complaining of worsening dysphagia. His upper gastrointenstinal endoscopy revealed a mass in the esophagus. A contrast-enhanced chest computed tomography also detected a 15 mm nodule attached to the tracheal membrane. This nodule was diagnosed as a metastatic lymph node. Although the primary tumor reduced after neoadjuvant chemotherapy, the nodule remained intact ; it showed fluorodeoxyglucose accumulation on positron emission tomography. We had a clinical diagnosis of stage III after neoadjuvant chemotherapy and underwent surgery. Intraoperatively, the nodule could not be detached from the right vagus nerve ; therefore, we excised the nodule along with the adjacent vagus nerve. The nodule was pathologically diagnosed as a vagus schwannoma. The nodule was not a regional lymph node metastasis of esophageal cancer. His postoperative course was uneventful, and he is currently undergoing outpatient follow-up without recurrence

MONITORING ANAPLASTIC THYROID CANCER MODELS BY PET/CT

Anaplastic thyroid carcinoma (ATC) is a rare type of thyroid carcinoma with a poor prognosis. Thus, suitable preclinical tumor models are required for the development of new ATC therapies. In the present study, orthotopic tumor xenograft models were established using ATC cell lines and SCID mice, and tumor invasion and the effects of anticancer drugs were evaluated using positron emission tomography/computed tomography (PET/CT) to repeatedly and non-invasively monitor these models. Three ATC cell lines (8305c, 8505c, and ACT-1) were used. Their sensitivities to two anticancer drugs (paclitaxel and lenvatinib) were investigated. The 8505c cell line was orthotopically implanted into SCID mice, which were then divided into three groups: no chemotherapy, paclitaxel (5 mg/kg, administered intraperitoneally, every week), and lenvatinib (5 mg/kg, oral route, every day) groups. PET/CT was performed and tumor growth and the effects of anticancer drugs based on tumor volume and fludeoxyglucose (FDG) uptake were evaluated. 8505c cells exhibited the highest sensitivity to the anticancer drugs. In mice implanted with 8505c cells, continuous increases in FDG uptake associated with tumor growth were detected on PET/CT in the group that received no chemotherapy. The tumor volume and FDG uptake increased by 91.5- and 2.4-fold, respectively, within 2 weeks. The increase observed in tumor volume was 26.9- and 12.2-fold in the paclitaxel and lenvatinib groups, respectively, within 2 weeks. Furthermore, the increase in FDG uptake was 1.8-fold and 1.6-fold in the paclitaxel and lenvatinib groups, respectively, within 2 weeks. In our orthotopic SCID mouse model, tumor growth and the effects of anticancer drugs were repeatedly and non-invasively monitored using PET/CT. The present method is useful for the development of new ATC treatments

Usefulness of peripherally inserted central catheters

Introduction : Central venous catheter (CVC) use is essential for treating esophageal cancer. Peripherally inserted central catheters (PICC) are commonly used recently for improved patient comfort and safety. We compared centrally inserted central catheters (CICC) and PICC insertions and examined their safety. Methods : We retrospectively investigated complications at the catheter insertion and post-insertion for 199 patients’ esophageal cancer treatment (CICC : 45, PICC : 154) from 2013 to 2018. In addition, we summarized the results of catheter tip culture. Results : No serious complications occurred at the catheter insertion in either group. The rate of complications at catheter insertion was 5.8% for PICC and 6.7% for CICC patients. Post-insertion complications were observed in 6.5% and 11.1% of patients with PICC and CICC, respectively, and this difference was not significant. The incidence of catheter-related blood stream infection (CRBSI) was significantly lower in PICC than CICC patients (0.3 vs. 1.8 / 1,000 catheter-days ; p = 0.029). Catheter-related thrombosis was observed in PICC : 0.5 and CICC : 0.6, and occlusion due to blood flow reversal was observed in PICC : 0.5 and CICC : 0.6. Conclusion : PICCs are safer and more effective than CICCs for the treatment of esophageal cancer, and reduce the incidence of CRBSI. We hope to standardize the insertion procedures, conventionalize techniques, and establish training systems

Successful Fitting of a Complete Maxillary Denture in a Patient with Severe Alzheimer’s Disease Complicated by Oral Dyskinesia

There is an increasing population of elderly patients suffering from Alzheimer’s disease (AD), the most common form of dementia. In dentistry, a critical problem associated with these patients is the use of a new denture, as AD patients often refuse dental management and are disturbed by minor changes in their oral environment. Some AD patients have further complications associated with oral dyskinesia, a movement disorder that can make dental management difficult, including the stability of a complete denture. In this case, we successfully fitted a complete maxillary denture using modified bilateral balanced occlusion after multiple tooth extractions under intravenous sedation in a 66-year-old woman with severe AD complicated by oral dyskinesia. Following treatment, her appetite and food intake greatly improved. Providing a well-fitting complete denture applied by modified bilateral balanced occlusion, which removes lateral interference using zero-degree artificial teeth for movement disorder of the jaw in patients with severe AD complicated by oral dyskinesia, helps improve oral function

DIP during perioperative chemotherapy

Purpose : Drug-induced interstitial pneumonia (DIP) that occurs during chemotherapy for breast cancer is a rare but a serious adverse event. Treatments of DIP requires interruption of breast cancer treatment, which may affect the patient’s prognosis. However, there are few reports which discuss DIP during breast cancer treatments. Purpose of this report is to make clear how DIP occurred and influenced breast cancer treatment in our hospital. Patients and Methods : A total of 74 patients who started perioperative chemotherapy in Tokushima Municipal Hospital for breast cancer from January 2019 to December 2020 were evaluated for DIP. Patients’ and tumors’ characteristics, and regimens which caused DIP were investigated. The clinical courses of the DIP patients were also followed up. Results : Twelve of the 74 patients developed DIP. All 12 patients had histories of cyclophosphamide administration ; however, the causative drug could not be determined. Ten of the 12 patients were treated with steroids, and all the patients recovered ultimately from the interstitial pneumonia. While chemotherapy was administered in six patients after mild DIP, no relapse of pneumonia was observed. Conclusion : DIP during perioperative chemotherapy for breast cancer was resolved with appropriate treatment. Patients were able to resume breast cancer treatment with minimal interruption

Colon cancer form a colonic graft

Neoplasm of a colonic graft after esophageal reconstruction is rare. We treated a colon cancer patient who developed malignancy in a colonic graft after esophagectomy and reconstruction through a retrosternal route. A male had undergone esophagectomy in his 50s due to a benign esophago-bronchial fistula. His dysphagia became exacerbated 20 years later, and further examinations showed a circumferential tumor on the esophago-colonic anastomosis. He underwent resection of the colonic graft adenocarcinoma with median sternotomy after neoadjuvant chemotherapy. Gastric tube reconstruction was performed through a retrosternal route. This report should be informative in terms of making decisions from an initial reconstruction to follow-up and choosing a therapeutic strategy for colonic graft cancer in the future

Japanese VLBI Network observations of radio-loud narrow-line Seyfert 1 galaxies

We performed phase-reference very long baseline interferometry (VLBI) observations on five radio-loud narrow-line Seyfert 1 galaxies (NLS1s) at 8.4 GHz with the Japanese VLBI Network (JVN). Each of the five targets (RXS J08066+7248, RXS J16290+4007, RXS J16333+4718, RXS J16446+2619, and B3 1702+457) in milli-Jansky levels were detected and unresolved in milli-arcsecond resolutions, i.e., with brightness temperatures higher than 10^7 K. The nonthermal processes of active galactic nuclei (AGN) activity, rather than starbursts, are predominantly responsible for the radio emissions from these NLS1s. Out of the nine known radio-loud NLS1s, including the ones chosen for this study, we found that the four most radio-loud objects exclusively have inverted spectra. This suggests a possibility that these NLS1s are radio-loud due to Doppler beaming, which can apparently enhance both the radio power and the spectral frequency.Comment: 8 pages, 2 figures, accepted for publication in PAS