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1.
Org Biomol Chem ; 19(6): 1344-1351, 2021 02 18.
Article in English | MEDLINE | ID: mdl-33471016

ABSTRACT

Facilitated by the dual role of Ceric Ammonium Nitrate (CAN), herein we report a cost-effective approach for the cyanation of aryl iodides/bromides with CAN-DMF as an addition to the existing pool of combined cyanation sources. In addition to being an oxidant, CAN acts as a source of nitrogen in our protocol. The reaction is catalyzed by a readily available Cu(ii) salt and the ability of CAN to generate ammonia in the reaction medium is utilized to eliminate the additional requirement of a nitrogen source, ligand, additive or toxic reagents. The mechanistic study suggests an evolution of CN- leading to the synthesis of a variety of aryl nitriles in moderate to good yields. The proposed mechanism is supported by a series of control reactions and labeling experiments.

2.
Org Lett ; 20(10): 2892-2896, 2018 05 18.
Article in English | MEDLINE | ID: mdl-29715031

ABSTRACT

Hydrogen gas can be generated from simple alkanes (e.g., n-pentane, n-hexane, etc.) and diethyl ether (Et2O) by mechanochemical energy using a planetary ball mill (SUS304, Fritsch Pulverisette 7), and the use of stainless steel balls and vessel is an important factor to generate the hydrogen. The reduction of organic compounds was also accomplished using the in-situ-generated hydrogen. While the use of pentane as the hydrogen source facilitated the reduction of the olefin moieties, the arene reduction could proceed using Et2O. Within the components (Fe, Cr, Ni, etc.) of the stainless steel, Cr was the metal factor for the hydrogen generation from the alkanes and Et2O, and Ni metal played the role of the hydrogenation catalyst.

3.
ChemSusChem ; 8(22): 3773-6, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26493945

ABSTRACT

A one-pot continuous-flow method for hydrogen (deuterium) generation and subsequent hydrogenation (deuterogenation) was developed using a stainless-steel (SUS304)-mediated ball-milling approach. SUS304, especially zero-valent Cr and Ni as constituents of the SUS304, and mechanochemical processing played crucial roles in the development of the reactions.


Subject(s)
Deuterium Oxide/chemistry , Deuterium/chemistry , Stainless Steel/chemistry , Hydrogenation
4.
Biosens Bioelectron ; 41: 465-70, 2013 Mar 15.
Article in English | MEDLINE | ID: mdl-23036773

ABSTRACT

Carbohydrate-mediated functions in biological systems have generated considerable interest in recent years. We have developed a device bearing immobilized carbohydrates on a colloidal gold surface and applied this device to the detection of carbohydrate-binding molecules by using localized surface plasmon resonance (LSPR) spectroscopy. The sensing device was constructed by using cyanuric chloride as an amine-linker between an amino residue of a polyamidoamine (PAMAM) dendrimer-coated colloidal gold surface and the amino residue of a 12-aminododecyl glycoside. After optimizing the construction of the device, we characterized its LSPR-based sensing capability. Binding specificity with lectins and linear range responses were obtained with the device. Our LSPR-based sensing device thus provides a label-free, low-cost detection method for use as a laboratory research tool or in medical glycan arrays.


Subject(s)
Biosensing Techniques/instrumentation , Carbohydrates/chemistry , Gold/chemistry , Lectins/analysis , Protein Interaction Mapping/instrumentation , Spectrum Analysis/instrumentation , Surface Plasmon Resonance/instrumentation , Binding Sites , Colloids/chemistry , Dendrimers/chemistry , Equipment Design , Equipment Failure Analysis , Lectins/chemistry , Protein Binding , Reproducibility of Results , Sensitivity and Specificity
5.
J Colloid Interface Sci ; 393: 257-63, 2013 Mar 01.
Article in English | MEDLINE | ID: mdl-23200344

ABSTRACT

The immobilization of carbohydrates on gold surfaces is a prerequisite technology for carbohydrate-related studies, including those of carbohydrate-biomolecule interactions. Glycolipid domains in cell membranes, such as lipid rafts, are thought to play an important role in cell biology through their carbohydrate portions. To understand the recognition of glycolipid domains such as receptors for bacterial toxins and viruses, we immobilized clusters of carbohydrates on a gold surface by using polyamidoamine (PAMAM) dendrimers as a scaffold. The PAMAM dendrimers were adsorbed on the gold-coated surface of a quartz crystal microbalance (QCM) sensor and were observed by means of QCM with dissipation (QCM-D). After adsorption of the PAMAM dendrimers, lysoganglioside-GM(1) and 12-aminododecyl-N-acetylglucosaminide (GlcNAc-C12-NH(2)) were immobilized on the amino groups of PAMAM dendrimers by means of an NH(2) cross-linker. Immobilization of the carbohydrates was confirmed by observation of their specific interaction with anti-ganglioside GM(1) antibody or wheat germ agglutinin (WGA). Surfaces with different GlcNAc-C12-NH(2) cluster sizes and densities were prepared by varying the size of the PAMAM dendrimers or the concentration of GlcNAc-C12-NH(2) immobilized on the dendrimers, respectively. Analysis of the binding between the GlcNAc-C12-NH(2)-immobilized surface and WGA revealed that the size of the PAMAM dendrimers influenced the GlcNAc-C12-NH(2)-WGA interaction, with larger dendrimers resulting in higher WGA binding constants.


Subject(s)
Carbohydrates/chemistry , Gold/chemistry , Quartz Crystal Microbalance Techniques , Adsorption , Dendrimers/chemistry , Molecular Structure , Polyamines/chemistry , Surface Properties
6.
Gan To Kagaku Ryoho ; 39(10): 1563-6, 2012 Oct.
Article in Japanese | MEDLINE | ID: mdl-23064073

ABSTRACT

S-1 and capecitabine are orally administered fluoropyridines reported to be effective in the treatment of advanced gastric cancer(AGC). In fact, both S-1/CDDP and capecitabine/CDDP are considered to be the standard first-line treatments for AGC.However, no information concerning on the activity of capecitabine in S-1-pretreated patients with AGC has been reported. Here, we present a case of recurrent gastric cancer that showed a partial response resulting in 6 months of progres-sion-free survival, thanks to capecitabine/CDDP after the failure of multiple anticancer drugs such as S-1/CDDP. S -1 and capecitabine may exhibit cross-resistance because they both have the same final active metabolite: 5-fluorouracil(5-FU). Dihydropyrimidine dehydrogenase(DPD)is the rate-limiting enzyme in the degradation of 5-FU, and S-1 contains the inhibitor of DPD. Thus, S-1, but not capecitabine, is active against tumors with high DPD expression. On the other hand, capecitabine is activated to 5-FU by thymidine phosphorylase(TP)within the tumor tissue and is more effective against tumors with high TP expression. The present case suggests that S-1 and capecitabine do not always exhibit cross-resistance, and that capecitabine may be effective in S-1-pretreated patients with AGC.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Stomach Neoplasms/drug therapy , Aged , Capecitabine , Cisplatin/administration & dosage , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Drug Combinations , Fluorouracil/administration & dosage , Fluorouracil/analogs & derivatives , Humans , Male , Oxonic Acid/administration & dosage , Recurrence , Salvage Therapy , Tegafur/administration & dosage
7.
Hepatol Res ; 42(1): 103-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22175800

ABSTRACT

Klinefelter's syndrome (KS) is a unique physical condition characterized by tall stature, eunuchoid body proportions, gynecomastia, and azoospermia, in addition to an extra X chromosome. In contrast to the original description, symptoms or physical findings can be extremely varied. KS is the most common chromosomal disorder, with an incidence of 1 in 500 males and is also the most commonly undiagnosed chromosomal disorder. Here, we present the case of a 26-year-old man with KS, who visited our hospital with complaints of abdominal pain and fever. On a routine physical examination, he did not differ from a normal karyotype male. Computed tomography showed extensive portal and mesenteric vein thrombosis (PMVT). It is well known that KS is frequently associated with venous thrombosis, but KS with PMVT has rarely been reported. Approximately one-third of PMVT is idiopathic, but this case suggests the possibility that undiagnosed KS is one of the causes of PMVT, as some individuals with KS are not easily distinguishable from those with the normal karyotype.

8.
Gan To Kagaku Ryoho ; 38(9): 1461-6, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21945893

ABSTRACT

BACKGROUND: S-1, an oral fluoropyrimidine, is one of the standard chemotherapeutic agents for the treatment of metastatic gastric cancer(MGC). However, the most effective second-line regimen after failure of treatment with first-line agents such as S-1 is yet to be determined. The aim of this study was to investigate the various second-line chemotherapy regimens in MGC patients. METHODS: We retrospectively studied patients with MGC who received second-line treatment after failure of the first-line S-1 or S-1/cisplatin treatment. The overall survival times with each second-line regimen were determined using the Kaplan-Meier method, and the effect on overall survival was analyzed using Cox regression analysis. RESULTS: The median survival time for all patients was 14. 2 months(95% confidence interval(CI): 12. 88-15. 43 months)with a 1-year survival rate of 60. 4%. Kaplan-Meier analysis revealed that the second-line regimens containing irinotecan significantly improved the median survival time as compared to regimens without irinotecan(median survival time: 16. 5 and 13. 8 months, respectively). Cox regression analysis showed that irinotecan-containing regimens were associated with improved overall survival(hazard ratio: 0. 165; 95% CI: 0. 041-0. 665). CONCLUSION: The use of irinotecan-containing regimens as second-line chemotherapy after failure of first-line S-1 therapy may be beneficial for MGC patients.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Camptothecin/analogs & derivatives , Drug Resistance, Neoplasm , Salvage Therapy , Stomach Neoplasms/drug therapy , Aged , Camptothecin/administration & dosage , Camptothecin/therapeutic use , Cisplatin/administration & dosage , Cisplatin/therapeutic use , Drug Combinations , Female , Humans , Irinotecan , Male , Neoplasm Metastasis , Oxonic Acid/administration & dosage , Oxonic Acid/therapeutic use , Retrospective Studies , Stomach Neoplasms/pathology , Tegafur/administration & dosage , Tegafur/therapeutic use
9.
Int J Clin Oncol ; 16(4): 428-34, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21069551

ABSTRACT

Recent advances in our understanding of the genetic mutations associated with melanoma have led to the classification of distinct melanoma subtypes. A number of reports have consistently demonstrated that mucosal and acral melanomas more commonly harbor KIT-activating mutations than do other subtypes. Success in treating gastrointestinal stromal tumors with imatinib has led to speculation that KIT-mutated melanoma might also be effectively managed using this approach. A 78-year-old woman presented with a 4-month history of rectal bleeding. A colonoscopy revealed a black polypoid mass, 30 mm in diameter, originating near the dentate line, and a biopsy revealed malignant melanoma. Computed tomography showed multiple liver and lung metastases. A KIT mutation analysis showed the L576P mutation in exon 11. The patient did not want to undergo chemotherapy including a tyrosine-kinase inhibitor, so palliative radiotherapy for rectal symptoms was performed, but the patient died 4 months later due to disease progression. We describe the first case of anorectal melanoma with a KIT-activating mutation in Japan and summarize findings from the literature regarding the efficacy of KIT kinase inhibitors on this melanoma subtype.


Subject(s)
Anus Neoplasms/genetics , Anus Neoplasms/pathology , Melanoma/genetics , Melanoma/pathology , Proto-Oncogene Proteins c-kit/genetics , Rectal Neoplasms/genetics , Rectal Neoplasms/pathology , Aged , Anus Neoplasms/radiotherapy , Female , Humans , Liver Neoplasms/secondary , Lung Neoplasms/secondary , Melanoma/radiotherapy , Palliative Care , Protein Kinase Inhibitors/therapeutic use , Proto-Oncogene Proteins c-kit/antagonists & inhibitors , Rectal Neoplasms/radiotherapy
10.
Gan To Kagaku Ryoho ; 37(11): 2115-9, 2010 Nov.
Article in Japanese | MEDLINE | ID: mdl-21084810

ABSTRACT

BACKGROUND: In Japan, esophagectomy with three-field lymphadenectomy is the standard therapy for resectable esophageal cancer. However, its outcome is considered unsatisfactory because the 5-year survival rate is less than 50%. Chemoradiotherapy (CRT) is the standard therapy for unresectable esophageal cancer and could also be considered as an option for resectable esophageal cancer. We retrospectively determined the efficacy and safety of CRT for patients with esophageal cancer. METHODS: The study population comprised patients with esophageal cancer who had been treated with CRT between April 2004 and October 2009 in our institute. Acute and late toxicity was assessed with NCI-CTC and RTOG/EORTC late radiation morbidity scoring scheme, respectively. Survival time was calculated using Kaplan-Meier methods. RESULTS: We enrolled 29 consecutive patients and classified them on the basis of clinical staging: stage I, 4 patients; stage II/III, 11 patients; and stage IV, 14 patients. Complete response was achieved in 37.9% and 45.5% of the total study population and the stage II/III group, respectively. The median survival time in these groups was 12.1 months and 15 months, respectively. Grade 3/4 acute toxicities were observed in 62.1% of the patients. Grade 3/4 late toxicities were observed in 12% of the patients. The first failure after CRT was almost locoregional. CONCLUSION: CRT appears to be an effective therapy for esophageal cancer; however, its outcome is not satisfactory. Therefore, it is necessary to evaluate the role of salvage surgery after CRT and new chemotherapeutic agents.


Subject(s)
Esophageal Neoplasms/therapy , Aged , Combined Modality Therapy , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/mortality , Esophageal Neoplasms/radiotherapy , Female , Humans , Male , Retrospective Studies , Salvage Therapy , Survival Rate
11.
Intern Med ; 48(5): 335-8, 2009.
Article in English | MEDLINE | ID: mdl-19252357

ABSTRACT

A male patient with chronic bloody stool was diagnosed as juvenile polyposis at the age of 28. He had thirty to forty colonic polyps and some were removed endoscopically, while gastric polyps were too numerous to intervene. As the polyposis advanced gradually, the patient developed intractable anemia and serious hypoproteinemia. Albumin scintigram revealed protein losing gastropathy due to progressive gastric polyposis. Total gastrectomy was carried out at the age of 34 and the patient has achieved remarkable and sustainable improvement.


Subject(s)
Intestinal Polyposis/complications , Polyps/complications , Protein-Losing Enteropathies/etiology , Stomach Diseases/complications , Adult , Disease Progression , Gastrectomy , Humans , Intestinal Polyposis/diagnosis , Intestinal Polyposis/surgery , Male , Polyps/diagnosis , Polyps/surgery , Protein-Losing Enteropathies/diagnosis , Protein-Losing Enteropathies/surgery , Stomach Diseases/diagnosis , Stomach Diseases/surgery
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