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Two new species of the interstitial genus Parvocythere (Crustacea, Ostracoda, Cytheroidea) from Japan: an example of morphological variation
Ryouichi Higashi,Akira Tsukagoshi
ZooKeys , 2012, DOI: 10.3897/zookeys.193.2842
Abstract: Two new species of the interstitial ostracod genus Parvocythere, P. gottwaldi sp. n. and P. gracilis sp. n., are herein described. Although these two new species are clearly distinguishable by certain morphological differences in elements of the male copulatory organ, and the carapace, they share the following simplified characters of the appendages and male copulatory organ: antennular fourth podomere with no suture; reduced claws on the distal end of antenna; and asymmetric male copulatory organ. The morphological differences among known and new Parvocythere species suggest that the species of this genus can be classified into two groups by the presence/absence of the suture on the antennular fourth podomere. The “Group S” is characterised by the presence of the antennular suture, and all species of this group have a two-clawed antenna and symmetric male copulatory organ, characters which are generally seen in cytheroid ostracods. The species belonging to “Group N” are characterised by the absence of the suture, regarded as a pedomorphic character, show the following characters: two clawed or one clawed antenna, and symmetric or asymmetric male copulatory organ. The morphological variation within Group N includes reductive characters regarded as an adaptation to the narrow spaces of the interstitial environment of a sandy beach. These intrageneric morphological variations of the exclusively interstitial genus Parvocythere suggest the possibilities that Group N might be derived from Group S, and that some adaptive characters to an interstitial environment could have developed after the colonisation of these environments.
Development of Simultaneous HPLC-Fluorescence Assay of Phenol and Chlorophenols in Tap Water after Pre-Column Derivatization with 3-Chlorocarbonyl-6,7-dimethoxy-1- methyl-2(1H)-quinoxalinone  [PDF]
Yasuhiko Higashi
Detection (Detection) , 2016, DOI: 10.4236/detection.2016.41003
Abstract: Chlorophenols (2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,6-dichlorophenol and 2,4, 6-trichlorophenol) may be presented in natural waters or drinking water as a result of disinfection processes involving chlorination, or as contaminants derived from domestic products, industrial operations and agricultural chemicals. A previous HPLC-UV method for determination of phenol and five chlorophenols in tap water using 4-fluoro-7-nitro-2,1,3-benzoxadiaole as a UV labeling reagent shows limited sensitivity. Here, we present an improved HPLC-fluorescence detection method for simultaneous determination of phenol and the above chlorophenols in tap water after pre-column derivatization with 3-chlorocarbonyl-6,7-dimethoxy-1-methyl-2(1H)-quino- xalinone (DMEQ-COCl), using a short, narrow column (50 × 2.1 mm i.d., packed with 5 μm particles of C18 material) to improve the sensitivity. Standard samples containing the compounds are derivatized with DMEQ-COCl in borate buffer (pH 9.0) at room temperature for 3 mins. The response is linear in the concentration range of 0.01 - 0.05 to 0.5 mg/L with r2 values ≥0.9967 for all compounds. The lower limits of detection are 0.001 to 0.008 mg/L, and the coefficients of variation are less than 8.8%. The recovery values from tap water spiked with standard samples are satisfactory. The present method is suitable for examining whether or not tap water samples are contaminated with phenol and chlorophenols in excess of regulatory values.
Simple HPLC-Fluorescence Determination of Raspberry Ketone in Fragrance Mist after Pre-Column Derivatization with 4-Hydrazino-7-nitro-2,1,3-benzoxadiazole  [PDF]
Yasuhiko Higashi
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2016, DOI: 10.4236/jasmi.2016.62006
Abstract: Raspberry ketone {RK, 4-(4-hydroxyphenyl)butan-2-one} is a natural compound contained in raspberry, and is added to cosmetics for skin whitening. It is very important to measure the RK level in cosmetics for quality assessment, since RK structurally resembles 4-(4-hydroxyphenyl)-2-butanol, which causes leukoderma on consumers’ skin. Here, we present a simple HPLC-fluorescence method for determination of RK in a fragrance mist by pre-column derivatization with 4-hydrazino-7-nitro-2,1,3-benzoxadiazole hydrazine (NBD-H), which reacts with the carbonyl group of RK. The NBD-RK derivative was eluted from a reversed-phase ODS column, and detected with excitation at 470 nm and emission at 550 nm. The retention time of NBD-RK derivative obtained by reaction with NBD-H at 80°C for 20 min was 10.3 min. The standard curve was linear in the range of 0.2 to 10 μg/mL, with a correlation coefficient (r2) value of 0.9980. The lower limit of detection was 0.018 μg/mL (absolute amount of 1.8 pmol). The coefficients of variation were less than 8.1%. The content of RK in fragrance mist (1.00 mL) was 1.18 ± 0.07 mg (range: 1.12 to 1.28 mg, n = 5). Recovery tests were satisfactory (83.9% ± 3.9%; range: 79.6 to 88.8%, n = 5).
Improved Method for Determination of Raspberry Ketone in Fragrance Mist by HPLC-Fluorescence Analysis after Pre-Column Derivatization with 4-(N,N-Dimethylaminosulfonyl)-7-(N-chloroformylmethyl-N-methylamino)-2,1,3-benzoxadiazole  [PDF]
Yasuhiko Higashi
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2018, DOI: 10.4236/jasmi.2018.82002
Abstract:

Raspberry ketone {RK, 4-(4-hydroxyphenyl)butan-2-one} is structurally resembles 4-(4-hydroxyphenyl)-2-butanol, which causes leukoderma on consumers’ skin. Therefore, it is important to measure in cosmetics for quality assessment. Very recently, an HPLC-fluorescence method for determination of RK in a fragrance mist by pre-column derivatization with 4-hydrazino-7-nitro-2,1,3-benzoxadiazole hydrazine was established. However, the derivatization conditions (80°C, 20 min) were severe. In this study, an improved pre-column derivatization with 4-(N,N-dimethylaminosulfonyl)-7-(N-chloro-formylmethyl-N-methylamino)-2,1,3-benzoxadiazole (DBD-COCl) is presented by HPLC-fluorescence method for determination of RK. The DBD-CO-RK derivative was eluted from a reversed-phase ODS column, and detected with excitation at 440 nm and emission at 543 nm. Derivatization was performed at room temperature for 3 min. The retention time of DBD-CO-RK derivative was 16.8 min. The standard curve was linear in the range of 0.05 to 2.5 μg/mL, with a correlation coefficient (r2) value of 0.9988. The lower limit of detection was 0.01 μg/mL (absolute amount of 0.3 pmol). The coefficients of variation were less than 10.0%. The content of RK in fragrance mist (1.00 mL) was 1.20 ± 0.08 mg (range, 1.10 to 1.31 mg,

Relationships between Length of the Antral Cuff and Postgastrectomy Disorders and Gastric Empting Function in Patients after Pylorus-Preserving Gastrectomy for Early Gastric Cancer  [PDF]
Ryouichi Tomita, Kenichi Sakurai, Shigeru Fujisaki
Journal of Cancer Therapy (JCT) , 2017, DOI: 10.4236/jct.2017.810076
Abstract: Objectives: To clarify the optimal length of the antral cuff (LAC) in patients after pylorus-preserving gastrectomy (PPG), we investigated relationships between LAC and postgastrectomy disorder (PGD) such as postprandial abdominal fullness (PAF), and between LAC and gastric empting function (GEF) in PPG patients. Background: The main cause of PGD in PPG patients has been considered to be LAC. Relationships between LAC and PGD and GEF in PPG patients are still unknown. Methods: Of 50 patients who underwent PPG in our hospital from January 2001 to December 2015 were divided into 2 groups [Group A, short LAC of 1.5 to 2.5 cm (n = 24); Group B, long LAC of 2.6 to 3.5 cm (n = 26)]. The relationships among LAC, PGD, and GEF were retrospectively studied. Results: LAC was clearly shorter in group A than group B (P < 0.01). PAF, appetite and food consumption per meal were clearly more favorable in group B than in group A (P < 0.01, respectively). Symptomatic reflux esophagitis (RE), early dumping syndrome, decreased percent body weight for pre-illness, endoscopic RE and endoscopic gastritis in the remnant stomach were more frequent in group A than group B. Gastric stasis in the remnant stomach was clearly more frequent in group A than group B (P < 0.01). GEF with the solid diet in group A was clearly more delayed than in group B (P
Simple HPLC Analysis of Hinokitiol in Skin Lotion with Visible Light Detection after Pre-Column Dabsylation  [PDF]
Yasuhiko Higashi, Shunsuke Tohda
American Journal of Analytical Chemistry (AJAC) , 2017, DOI: 10.4236/ajac.2017.85026
Abstract: Hinokitiolis frequently added to personal care products as an antibacterial agent. We previously established an HPLC-UV method for determination of hinokitiol in skin lotion after pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole. However, the labeling reagent is expensive, and derivatives of degradation products of parabens, which may be added to skin lotion as general preservatives, interfered with the peak of the hinokitiol derivative. In this study, the concentration of hinokitiol in skin lotions was determined by HPLC with a visible light detector (450 nm) after pre-column derivatization with 4-(dimethylamino)azobenzene-4’-sulfonyl chloride (Dabsyl-Cl), a more economical reagent. A standard curve was obtained after derivatization with Dabsyl-Cl in borate buffer (pH 9.5) at 55°C for 10 min. The retention time of Dabsyl-hinokitiol was 6.8 min. The calibration plot was linear in the range of 1.25 to 40 μg/mL with a r2 value of 0.9991, and the lower limit of quantification and detection were 0.60 μg/mL (absolute amount of 0.86 ng/20μL injection, signal-to-noise ratio of 10:1) and 0.18 μg/mL (absolute amount of 0.26 ng/20μL injection, signal-to-noise ratio of 3:1), respectively. The coefficient of variation was less than 8.8%. Seven Dabsyl-paraben derivatives showed little interference with the peak of Dabsyl-hinokitiol. The developed system was used to determine the content of hinokitiol in two skin lotions. Addition-recovery tests gave satisfactory results.
Long-Term Survival after Resection for Primary Undifferentiated Pleomorphic Sarcoma of the Jejunum with Lymph Node Metastases: Case Report  [PDF]
Shigeru Fujisaki, Motoi Takashina, Kenichi Sakurai, Ryouichi Tomita, Tadatoshi Takayama
Journal of Cancer Therapy (JCT) , 2017, DOI: 10.4236/jct.2017.812092
Abstract: Primary undifferentiated pleomorphic sarcoma (UPS) of the small intestine is extremely rare. The prognosis of UPS is basically poor, and particular, when accompanied with metastatic lesions. This paper reports the case of a long-term survivor of primary UPS of the jejunum with lymph node metastases and a skip lesion in the jejunum. The patient was a 50-year-old Japanese man who presented with a chief complaint of breathlessness. Small bowel X-ray series revealed an approximately 4-cm size with protruded lesion (image shows a filling defect) in the proximal jejunum. Based on a presumptive diagnosis of the hemorrhagic small bowel tumor, he underwent a laparotomy. A tumor was observed in the jejunum at approximately 90-cm from the Treitz ligament; some swollen mesenteric lymph nodules were also observed. Segmental resection of the jejunum was performed 20-140 cm from the Treitz ligament. A complete surgical excision with en-bloc regional lymph node dissection was performed. The final histopathological diagnosis was UPS of the jejunum with metastatic lymph nodes and a skip lesion in the jejunum. The postoperative course was uneventful. The patient was not given adjuvant chemotherapy and was discharged on postoperative day 16. He is currently well without any evidence of recurrence for >10 years after the operation.
Relationship between Gastric Stasis in the Remnant Stomach and Interdigestive Migrating Complex in Patients after Pylorus-Preserving Gastrectomy for Gastric Cancer  [PDF]
Ryouichi Tomita, Kenichi Sakurai, Shigeru Fujisaki, Takeo Azuhata, Yuko Takamoto
Journal of Cancer Therapy (JCT) , 2018, DOI: 10.4236/jct.2018.99055
Abstract: Objectives: The demerit of pylorus-preserving gastrectomy (PPG) is gastric stasis in the remnant stomach (GSRS). We investigated the relationship between postgastrectomy disorder (PGD), especially GSRS, and interdigestive migrating complex (IMC) in PPG patients. Background: The cause of GSRS is still unknown. Therefore, we studied relationship between GSRS and IMC. Methods: 24 PPG patients (16 men and 8 women; mean, 61.2 years) were divided into groups A (12 patients without GSRS) and B (12 patients with GSRS). The relationship between GSRS and IMC was studied. Results: Length of the antral cuff (LAC) was significantly longer in group A than group B (P < 0.0001). IMC and appetite were significantly more common in group A than in group B (P = 0.0465, P = 0.0186, respectively). Postprandial abdominal fullness (PAF) was significantly more common in group B than in group A (P = 0.0061). Reflux esophagitis (RE) and body weight loss were found in group B more than in group A. Dumping syndrome was not found in either group. Endoscopic gastritis was found significantly more in group B than in group A (P = 0.0047). Conclusions: In PPG patients with a short LAC, GSRS may occur by the decrease of IMC occurrence.
Lessons learned in the development of process quality indicators for cancer care in Japan
Takahiro Higashi
BioPsychoSocial Medicine , 2010, DOI: 10.1186/1751-0759-4-14
Abstract: In Japan, interest in ensuring the quality of patient health care has recently increased. Although Japanese citizens have enjoyed universal health insurance coverage for more than 40 years, concern has been expressed at the lack of an efficient system for monitoring the quality of care[1,2]. To date, quality monitoring has been sporadic at best[3,4], and organized efforts to improve quality have yet to be established. In the area of cancer care, this concern led to the enactment of the Cancer Control Act in 2006, which mandated that the government adopt a leadership role and take responsibility in ensuring the quality of cancer care nationwide[5]. However, ensuring quality care first requires an efficient means of measuring it.To this end, in 2006 the Japanese government funded a research project aimed at developing a system for measuring the quality of cancer care, focusing primarily on the five major types of cancer in Japan, namely breast, lung, stomach, colorectal, and liver cancer, as well as palliative care. Given that the project was aimed at measuring quality in terms of how current best practice was applied, rather than the general suitability of services (such as waiting times or the comfort of hospital beds), we sought extensive involvement from nationally recognized clinical experts in respective clinical areas. Methodology was under the direction of an epidemiologist and a health services researcher, while the contents of quality measurement were primarily defined by clinicians.An overview of the study was published in Japanese[6]. Briefly, we developed a total of 206 process-of-care quality indicators for cancer care using methodology developed by the researchers at University of California, Los Angeles and RAND Corporation[7-12]. This involved creating a set of candidate quality indicators, compiling evidence to support these indicators, and having a panel of multidisciplinary experts examine them for validity in two rounds of rating (scale of 1-9), o
La mise en voix del Cantar de Mio Cid y el Códice de Vivar
Higashi,Alejandro;
Olivar , 2007,
Abstract: in the last years, the musical performance has taken an important place in the study of the mise en voix of the cantar de mio cid. although this perspective is laudable in many ways, i propose to take care on the textual and codicological plane, because many of the musical traces are lost for distinct reasons: the condition of the copy, finished according to the historiographical patterns of the medieval scriptorium; the indirect knowledge of the medieval epic music; the gaps in the understanding of how medieval cantillation was performed during public workship, in the laic or clerical life; the influence (or not) of the medieval chant dialects (especially, mozarabic and eugenian chants), etc.
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