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1.
Asian J Endosc Surg ; 16(3): 627-630, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37280095

RESUMEN

Here, we report the first case of laparoscopic surgery to repair an incarcerated colonoscope in an inguinal hernia containing the sigmoid colon. After colonoscopy was performed on a 74-year-old man with positive fecal occult blood test results, the colonoscope could not be withdrawn. A bulge consistent with an incarcerated colonoscope was found on examination of the patient's left inguinal area. Computed tomography revealed and led to the diagnosis of an incarcerated colonoscope in the sigmoid colon within the inguinal hernia. After confirmation during emergency laparoscopic surgery, the incarcerated sigmoid colon was reduced, and the colonoscope was removed under radiographic and laparoscopic guidance. No ischemic changes or serosal injuries were observed, averting the need for resection. A transabdominal preperitoneal approach with a mesh was then used to repair the inguinal hernia laparoscopically. The patient's postoperative recovery was uneventful, and no recurrence was observed at the 1-year follow-up.


Asunto(s)
Hernia Inguinal , Laparoscopía , Masculino , Humanos , Anciano , Hernia Inguinal/complicaciones , Hernia Inguinal/diagnóstico por imagen , Hernia Inguinal/cirugía , Colon Sigmoide/cirugía , Herniorrafia/métodos , Laparoscopía/métodos , Colonoscopía
2.
Case Rep Oncol ; 14(2): 1124-1133, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34413743

RESUMEN

Immune-checkpoint inhibitors (ICIs) play a crucial role in the treatment of advanced nonsmall cell lung cancer (NSCLC); however, most patients fail this treatment after a limited period. We here report a patient with a pathological complete response after treatment with ICI for stage IV pulmonary adenocarcinoma. A 73-year-old man was referred to our hospital because of hoarseness. A roentgenogram and chest CT scan revealed a huge (78-mm diameter) pulmonary tumor in the right upper lobe and a tumor with cavitation in the left lower lobe. A CT scan also showed enlarged upper mediastinal lymph nodes (LNs). Transbronchial lung biopsy of the tumors showed adenocarcinomas in both. The tumor in the right upper lobe was considered to be the primary with mediastinal LNs metastasis and that in the left lower lobe a pulmonary metastasis. The disease was determined to be cT4N2M1a stage IVA. He was treated with first-line chemotherapy comprising cisplatin, pemetrexed, and bevacizumab for 6 cycles. However, 6 months after initial treatment, the primary and metastatic tumors enlarged, and he was treated with second-line anti-programed death 1 therapy for 7 months with a partial response. 18-fluorodeoxyglucose positron emission tomography (FDG-PET) revealed weak accumulation of FDG in the primary tumor only with no accumulation in the left pulmonary metastasis or mediastinal lymph node (LNs), despite the LNs still being enlarged. He was diagnosed as having ycT1bN0M0 stage IA2 disease and underwent right upper lobectomy. Postoperative pathological findings revealed that cancer tissues had been replaced by scar tissue and that CD4-positive T cells, rather than CD8-positive T cells, were predominant. It was also noted that he had a lower neutrophil-to-lymphocyte ratio (NLR) during immunotherapy than before immunotherapy and after surgery. He was diagnosed to be ypT0N0M0 stage 0 (Ef.3). His postoperative course was uneventful, and he remained well for 12 months after surgery with no further treatment. Neoadjuvant chemotherapy with ICIs for advanced NSCLC may be a promising modality, even for clinical stage IV disease, in the near future. Furthermore, NLR during immunotherapy may be a promising biomarker of ICIs treatment.

4.
Chemistry ; 24(71): 18907-18912, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30353923

RESUMEN

Asimicin (1) exhibits potent antitumor activity and comprises a central C2 -symmetric bis-tetrahydrofuran and two aliphatic side-chains, one of which terminates with (S)-methyl-2(5H)-furanone. This work reports a convergent total synthesis of 1 in 17 steps from d-gulose derivative 4. Decarbonylative radical-radial homo-coupling of α-alkoxyacyl telluride 12 a efficiently produced the C2 -symmetric core 3-SS, which was transformed into 1 through stepwise attachment of the two side-chains and functional group manipulations.

5.
J Am Chem Soc ; 139(5): 1814-1817, 2017 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-28092952

RESUMEN

Zaragozic acid C (1) was isolated as a potent squalene synthase inhibitor. The 2,8-dioxabicyclo[3.2.1]octane core of 1 is decorated with the three hydroxycarbonyl (C3,4,5), two hydroxy (C4,7), one acyloxy (C6), and one alkyl (C1) groups. Installation of the contiguous C4- and C5-fully substituted carbons presents a formidable synthetic challenge. Our approach to address this problem used a two-step photochemical C(sp3)-H acylation. Persilylated d-gluconolactone 4 was derivatized into 3 with the 1,2-diketone moiety at the C5-tetrasubstituted center. Norrish-Yang cyclization of 3 under violet LED irradiation followed by oxidative opening of the resultant α-hydroxycyclobutanone regio- and stereoselectively transformed the electron-rich tertiary C(sp3)-H bond at C4 into a C(sp3)-C bond to produce densely functionalized 2. A subsequent series of judicious functional group transformations gave rise to 1.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/síntesis química , Acilación , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Ciclización , Conformación Molecular , Procesos Fotoquímicos
6.
Chemistry ; 22(1): 222-9, 2016 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-26616151

RESUMEN

Ryanodine (1) is a potent modulator of intracellular calcium release channels, designated as ryanodine receptors. The exceptionally complex molecular architecture of 1 comprises a highly oxygenated pentacyclic system with eleven contiguous stereogenic centers, which makes it a formidable target for organic synthesis. We identified the embedded C2 -symmetric tricyclic substructure within 1. This specific recognition permitted us to design a concise synthetic route to enantiopure tricycle 9 by utilizing a series of pairwise functionalizations. The four tetrasubstituted carbon centers of 9 were effectively constructed by three key reactions, a dearomatizing Diels-Alder reaction, the kinetic resolution of the obtained racemic 14 through asymmetric methanolysis, and the transannular aldol reaction of the eight-membered diketone 10. A new combination of cobalt-catalyzed hydroperoxidation and NfF-promoted elimination enabled conversion of the hindered olefin of 9 into the corresponding ketone, thus realizing the desymmetrization. Finally, the tetrasubstituted carbon was stereospecifically installed by utilizing the α-alkoxy bridgehead radical to deliver the core tetracycle 7 with the six contiguous tetrasubstituted carbon centers. Consequently, the present work not only accomplishes efficient assembly of four out of the five fused rings of 1, but also develops two new powerful methodologies: two-step ketone formation and bridgehead radical reaction.


Asunto(s)
Alquenos/química , Hidrocarburos Aromáticos con Puentes/química , Hidrocarburos Aromáticos con Puentes/síntesis química , Cetonas/química , Rianodina/química , Rianodina/síntesis química , Catálisis , Reacción de Cicloadición , Estructura Molecular , Oxidación-Reducción , Estereoisomerismo
7.
Electrophoresis ; 29(7): 1423-30, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18384021

RESUMEN

A new scheme has been described for continuous particle separation using EOF in microfluidic devices. We have previously reported a method for particle separation, called "pinched flow fractionation (PFF)", in which size-dependent and continuous particle separation can be achieved by introducing pressure-driven flows with and without particles into a pinched microchannel. In this study, EOF was employed to transport fluid flows inside a microchannel. By controlling the applied voltage to electrodes inserted in each inlet/outlet port, the flow rates from both inlets, and flow rates distributed to each outlet could be accurately tuned, thus enabling more effective separation compared to the pressure-driven scheme. In the experiment, the particle behaviors were compared between EOF and pressure-driven flow schemes. In addition, micrometer- and submicrometer-sized particles were accurately separated and individually collected using a microchannel with multiple outlet branch channels, demonstrating the high efficiency of the presented scheme.


Asunto(s)
Microfluídica/instrumentación , Modelos Teóricos , Reproducibilidad de los Resultados
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