Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
Add more filters










Database
Publication year range
1.
ACS Nano ; 17(12): 11318-11326, 2023 Jun 27.
Article in English | MEDLINE | ID: mdl-37272845

ABSTRACT

Understanding the catalytic mechanism of highly active two-dimensional electrocatalysts is crucial to their rational design. Herein, we reveal the element dependence of the reactivity of two-dimensional metal dichalcogenide sheets for electrocatalytic CO2 reduction. We found that tin(IV) disulfide (SnS2) and molybdenum(IV) disulfide (MoS2) sheets exhibited Faradaic efficiencies of 63.3% and ∼0%, respectively, for formic acid. Scanning electrochemical cell microscopy and theoretical calculations were used to identify the catalytically active sites of SnS2 as terraces and edges. Owing to the effective utilization of the entire surface area, SnS2 can effectively accelerate catalytic reactions. This finding provides a direction for material research in two-dimensional electrocatalysts for energy-efficient chemical production from electrochemical CO2 reduction, as well as for other energy devices.

2.
Gan To Kagaku Ryoho ; 50(13): 1768-1770, 2023 Dec.
Article in Japanese | MEDLINE | ID: mdl-38303201

ABSTRACT

We report a case of locally advanced rectal cancer that could not be curatively resected, in which the patient underwent conversion surgery after chemotherapy. The patient is a 70-year-old woman. She came to our hospital with a chief complaint of lower abdominal pain, and a close examination revealed rectal cancer with invasion of the external iliac artery and pelvic wall. She was treated with mFOLFOX6 plus cetuximab for locally advanced rectal cancer that was not amenable to surgical resection. After 11 courses of chemotherapy, significant shrinkage of the tumor was observed, and robot assisted laparoscopic high-anterior resection was performed. The patient didn't relapse at 12 months after surgery without adjuvant chemotherapy.


Subject(s)
Laparoscopy , Rectal Neoplasms , Female , Humans , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasm Recurrence, Local/surgery , Rectal Neoplasms/drug therapy , Rectal Neoplasms/surgery , Rectal Neoplasms/pathology , Chemotherapy, Adjuvant
3.
Gan To Kagaku Ryoho ; 50(13): 1903-1905, 2023 Dec.
Article in Japanese | MEDLINE | ID: mdl-38303247

ABSTRACT

The patient is a 70s woman. She underwent cystectomy for bladder cancer 6 years ago and had a ureterocutaneous fistula in the right lower abdomen. After colonoscopy for positive fecal occult blood, a type 1 elevated lesion was found in the ascending colon, which was diagnosed as a well-differentiated adenocarcinoma on biopsy. Surgery was performed with a single hole. The approach from the right lower abdomen, where the ureterocutaneous fistula and ureter are located, was avoided, and the approach from the hepatic flexure of the transverse colon was used first. After the right colon was mobilized, the large mesh adhesions around the ureter were carefully dissected, and the right ureter was identified and preserved, extending from the lateral ascending colon to the abdominal wall. The ileal artery was dissected at the root and after dissection of the D3 lymph node, the intestine was dissected and anastomosed extracorporeally. The operative time was 246 minutes with small amount of blood loss. The patient was discharged on the 6th postoperative day without any postoperative complications. The pathology result was pT3N0M0, pStage Ⅱa, and radical resection had been performed. The patient is currently undergoing recurrence-free follow-up.


Subject(s)
Colonic Neoplasms , Fistula , Laparoscopy , Female , Humans , Abdomen/pathology , Biopsy , Colon, Ascending/surgery , Colonic Neoplasms/surgery , Fistula/surgery , Aged
4.
Biochem Biophys Res Commun ; 609: 48-53, 2022 06 18.
Article in English | MEDLINE | ID: mdl-35413539

ABSTRACT

Characteristics of peritubular myoid cells (PMCs) in sexually immature cattle remain largely unknown. Here, we report the character and behavior of peritubular cells expressing alpha smooth muscle actin (αSMA), a marker of PMCs in adult testes, in prepubertal testes procured from 5-months-old bulls. Elastin distribution around αSMA + PMCs was dim and discontinuous in prepubertal testes, but strong and continuous in adult testes. Fibroblast-specific protein 1 (FSP1) was rarely expressed in αSMA + PMCs of prepubertal testes, while in adult testes, majority of αSMA + PMCs were FSP1+. Moreover, αSMA + PMCs in prepubertal testes proliferated more actively than those in adult testes. In vitro culture of isolated seminiferous tubules from prepubertal testes revealed that αSMA + PMCs migrate from peritubular to interstitial area. Hence, in prepubertal bovine testes, (1) PMCs rarely portray fibroblast-like properties, (2) PMCs exhibit heterogeneity in FSP1 expression, (3) PMCs proliferate more actively than those in adult testes, and (4) PMCs have a potential to migrate to the interstitium. Our observations help to understand the maturation of PMCs and their involvement in bovine testicular function.


Subject(s)
Actins , Testis , Actins/metabolism , Animals , Cattle , Fibroblasts/metabolism , Male , Muscle, Smooth/metabolism , Seminiferous Tubules/metabolism , Testis/metabolism
5.
Anal Chem ; 93(43): 14448-14453, 2021 Nov 02.
Article in English | MEDLINE | ID: mdl-34668693

ABSTRACT

The discharged state affects the charge transfer resistance of lithium-ion secondary batteries (LIBs), which is referred to as the depth of discharge (DOD). To understand the intrinsic charge/discharge property of LIBs, the DOD-dependent charge transfer resistance at the solid-liquid interface is required. However, in a general composite electrode, the conductive additive and organic polymeric binder are unevenly distributed, resulting in a complicated electron conduction/ion conduction path. As a result, estimating the DOD-dependent rate-determining factor of LIBs is difficult. In contrast, in micro/nanoscale electrochemical measurements, the primary or secondary particle is evaluated without using a conductive additive and providing an ideal mass transport condition. To control the DOD state of a single LiFePO4 active material and evaluate the DOD-dependent charge transfer kinetic parameters, we use scanning electrochemical cell microscopy (SECCM), which uses a micropipette to form an electrochemical cell on a sample surface. The difference in charge transfer resistance at the solid-liquid interface depending on the DOD state and electrolyte solution could be confirmed using SECCM.

6.
J Antibiot (Tokyo) ; 69(4): 299-312, 2016 04.
Article in English | MEDLINE | ID: mdl-26905756

ABSTRACT

An efficient and versatile synthetic method for labile polyphenols was established using 2-nitrobenzenesulfonate (Ns) as a protecting group for phenol. This methodology provides regio- and stereoselective access to a range of methylated catechins, such as methylated epigallocatechin gallates, that are not readily available from natural sources. In addition, biomimetic synthesis of theaflavins from catechins was accomplished using Ns protection to minimize undesired side reactions of electron-rich aromatic rings during oxidation, enabling construction of the complex benzotropolone core in a single-step oxidative coupling reaction. Availability of these compounds will aid detailed structure-biological activity relationship studies of catechins.


Subject(s)
Benzenesulfonates/chemistry , Biflavonoids/chemical synthesis , Catechin/chemical synthesis , Polyphenols/chemical synthesis , Antioxidants/chemistry , Biflavonoids/chemistry , Catechin/analogs & derivatives , Catechin/chemistry , Methylation , Oxidation-Reduction , Structure-Activity Relationship
7.
Org Lett ; 16(7): 1976-9, 2014 Apr 04.
Article in English | MEDLINE | ID: mdl-24660822

ABSTRACT

The total synthesis of hedyotol A (1), a natural product isolated from Hedyotis lawsoniae (DC.) Wight et Arn. (Rubiaceae), was accomplished in a highly stereocontrolled manner. Key steps include an L-proline-catalyzed cross-aldol reaction and the biomimetic construction of a furofuran lignan skeleton through a quinomethide intermediate.


Subject(s)
Benzofurans/chemical synthesis , Biological Products/chemical synthesis , Lignans/chemical synthesis , Benzofurans/chemistry , Benzofurans/isolation & purification , Biological Products/chemistry , Biological Products/isolation & purification , Lignans/chemistry , Lignans/isolation & purification , Molecular Structure , Proline/analogs & derivatives , Proline/chemistry , Rubiaceae/chemistry , Stereoisomerism
SELECTION OF CITATIONS
SEARCH DETAIL
...