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1.
J Am Chem Soc ; 144(5): 2107-2113, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35084841

RESUMO

Catalytic imidation using NFSI as the nitrogen source has become an emerging tool for oxidative carbon-nitrogen bond formation. However, the less than ideal benzenesulfonimide moiety is incorporated into products, severely detracting its synthetic value. As a solution to this challenge, we report herein the development of a novel N-fluorinated imide, N-fluoro-N-(fluorosulfonyl)carbamate (NFC), by which the attached imide moiety acts as a modular synthetic handle for one-step derivatization to amines, sulfonamides, and sulfamides. Furthermore, this study revealed the superior reactivity of NFC as showcased in a copper-catalyzed imidation of benzene derivatives and imidocyanation of aliphatic alkenes, overcoming the limitation of NFSI-mediated reactions.

2.
J Chem Phys ; 156(18): 184117, 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35568559

RESUMO

In order to demonstrate an applicability of quantum computing to fundamental electronic structure problems of molecules, we describe the Hückel Hamiltonian matrix in terms of quantum gates and obtain the orbital energies of fundamental π-electron molecules (C2H4, C3H4, C4H4, C4H6, and C6H6) using a superconducting-qubit-type quantum computer (ibm_kawasaki) with a post-selection error mitigation method. We show that the orbital energies are obtained with sufficiently high accuracy and small uncertainties and that characteristic features of the electronic structure of the π-electron molecules can be extracted by quantum computing in a straightforward manner.

3.
Epilepsia ; 57(7): 1169-78, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27254541

RESUMO

OBJECTIVE: To investigate whether the magnetoencephalography (MEG) single moving dipole (SMD) method could delineate the epileptic zone of focal cortical dysplasia (FCD) at the bottom of sulcus (FCDB). METHODS: We retrospectively analyzed 17 children (11 male; mean age 8.8 years, range 3-17 years) with FCD type II who underwent epilepsy surgery. We compared spatial congruence between the following: (1) MEG cluster and FCDB and (2) MEG cluster and FCD at the brain surface (FCDS). We measured the volume and depth of magnetic resonance imaging (MRI)-visible lesions to investigate whether they affect spatial congruence between MEG cluster and MRI-visible lesion. RESULTS: Eight children had FCDB and the other nine children had FCDS. The volume of MRI-visible lesions for FCDB ranged from 1,632 to 4,707 mm(3) (mean ± standard deviation [SD] 3,095 ± 1,211 mm(3) ). The depth of FCDB ranged from 19 to 33 mm (mean ± SD 26 ± 4 mm). The volume of MRI-visible lesion for FCDS ranged from 2,375 to 57,331 mm(3) (15,470 ± 18,455 mm(3) ). There was a tendency for a smaller volume of MRI-visible lesion for FCDB, relative to FCDS(p = 0.079). In FCDB, six children showed clusters of MEG dipoles and two children showed scattered MEG dipoles for interictal spikes. The spatial congruence between the MEG result and FCDB was partially overlapping in four children and discordant in another four children. In FCDS, eight children had MEG cluster and one child had MEG scatter alone. The spatial congruence between MEG result and FCDS was overlapping in eight of nine children (fully two; partially six) and discordant in one of nine children. Fifteen children (88%; FCDB eight; FCDS seven) became seizure-free after resective surgery. MEG spike dipole resection ratio in the cluster ranged from 4-100% (mean 67%) in 6 FCDB and 23-99% (mean 77%) in 8 FCDS. SIGNIFICANCE: The SMD method may drift MEG spike dipoles for FCDB. Lesionectomy can control seizures for four of eight patients in FCDB despite the remote MEG dipoles. The FCDB or FCDS partially overlapped with MEG cluster may have an extending/invisible epileptogenic zone consecutive to the MRI-visible lesion.


Assuntos
Ondas Encefálicas/fisiologia , Encéfalo/fisiopatologia , Epilepsia/patologia , Epilepsia/fisiopatologia , Magnetoencefalografia , Malformações do Desenvolvimento Cortical do Grupo I/patologia , Malformações do Desenvolvimento Cortical do Grupo I/fisiopatologia , Adolescente , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Criança , Pré-Escolar , Eletroencefalografia , Epilepsia/classificação , Epilepsia/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Malformações do Desenvolvimento Cortical do Grupo I/classificação , Malformações do Desenvolvimento Cortical do Grupo I/diagnóstico por imagem , Estudos Retrospectivos
4.
Acute Med Surg ; 11(1): e940, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481627

RESUMO

Background: Cardiopulmonary resuscitation is essential for cardiopulmonary arrest, but complications from chest compressions warrant monitoring. Although rib and sternal fractures are common, abdominal injuries are rare, and splenic injuries are much rarer. Case Presentation: A 74-year-old man was admitted to the emergency room with a hemorrhagic duodenal ulcer. During hospitalization, the patient went into cardiopulmonary arrest due to hemorrhagic shock. Spontaneous circulation returned after 7 min of cardiopulmonary resuscitation. He underwent transcatheter arterial embolization to stop the bleeding from the duodenal ulcer. The next day, a close examination of the patient's progressive anemia revealed splenic injury; transcatheter arterial embolization was performed to save his life. Conclusion: It is important to consider the complication of splenic injury in patients with cardiopulmonary arrest who have undergone appropriate cardiopulmonary resuscitation. A possible mechanism-especially in patients with a full stomach-is the squeezing of the spleen by the diaphragm, abdominal wall, and stomach.

5.
Acute Med Surg ; 10(1): e899, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37814653

RESUMO

Background: We describe a case of segmental arterial mediolysis in which a vessel ruptured on two consecutive days. Case Presentation: A 69-year-old man presented with sudden-onset abdominal pain. Computed tomography showed a hematoma in the gastric wall. The patient was discharged after the pain was relieved but returned 8 h later with abdominal pain and shock. Repeated computed tomography revealed a massive intra-abdominal hemorrhage without previous aneurysm formation. Emergency angiography and coil embolization were successfully carried out. Segmental arterial mediolysis was diagnosed after irregular vasodilated lesions were observed in multiple arteries. Conclusion: This case suggests that accurately predicting the next vessel rupture is difficult. For patients experiencing intra-abdominal bleeding with segmental arterial mediolysis, we suggest treating only ruptured aneurysms and closely following-up unruptured aneurysms.

6.
Acute Med Surg ; 8(1): e635, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33659066

RESUMO

BACKGROUND: Heat stroke treatment focuses on rapid cooling because symptom severity correlates with the duration of hyperthermia (i.e., time during which the core body temperature is sustained above the critical threshold). Several reports have revealed that cold-water immersion is a safe and appropriate therapy for exertional heat stroke in young, otherwise healthy patients. However, few reports have assessed cold-water immersion in older patients. We document three cases of cold-water immersion in older heat stroke patients and evaluate its safety and efficacy. CASE PRESENTATION: Three older patients with severe heat stroke were treated with cold-water immersion. Core body temperatures decreased rapidly, and no complications occurred during the treatment. CONCLUSION: Cold-water immersion can achieve rapid cooling and is effective in treating heat stroke. With special precautions, it can be performed safely for older patients. Further investigation is warranted to establish appropriate cooling methods in older adults.

7.
J Antibiot (Tokyo) ; 68(5): 328-33, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25464973

RESUMO

In our effort to find the key intermediates of lankacidin biosynthesis in Streptomyces rochei, three UV-active compounds were isolated from mutant FS18, a gene disruptant of lkcA encoding a non-ribosomal peptide synthetase (NRPS)-polyketide synthase (PKS) hybrid enzyme. Their structures were elucidated on the basis of spectroscopic data of NMR and MS. Two compounds of a higher mobile spot on silica gel TLC (Rf=0.45 in CHCl3-MeOH=20:1) were determined to be an epimeric mixture of citreodiol and epi-citreodiol at the C-6 position in the ratio of 2:1. In contrast, the compound of a lower mobile spot (Rf=~0 in CHCl3-MeOH=20:1) was identical to a 28-membered polyene macrolide pentamycin. The yields of citreodiols and pentamycin in FS18 were 5- and 250-fold higher compared with the parent strain. Introduction of a second mutation of srrX, coding a biosynthetic gene of the signaling molecules SRBs, into mutant FS18 did not affect the production of three metabolites. Thus, their production was not regulated by the SRB signaling molecules in contrast to lankacidin or lankamycin.


Assuntos
Regulação Bacteriana da Expressão Gênica/fisiologia , Macrolídeos/metabolismo , Polienos/metabolismo , Streptomyces/metabolismo , Estrutura Molecular , Mutação , Transdução de Sinais
8.
Dalton Trans ; (1): 144-9, 2004 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-15356753

RESUMO

Fluoroacid-base reactions of a room-temperature ionic liquid, 1-ethyl-3-methylimidazolium fluorohydrogenate (EMIm(HF)2.3F, EMIm = 1-ethyl-3-methylimidazolium cation), and Lewis fluoroacids (BF3, PF5, AsF5, NbF5, TaF5 and WF6) give EMIm salts of the corresponding fluorocomplex anions, EMImBF4, EMImPF6, EMImAsF6, EMImNbF6, EMImTaF6 and EMImWF7, respectively. Attempts to prepare EMImVF6 by both the acid-base reaction of EMIm(HF)2.3F with VF5 and the metathesis of EMImCl with KVF6 failed due to the strong oxidizing power of the pentavalent vanadium, whereas EMImSbF6 was successfully prepared only by the metathesis of EMImCl and KSbF6. EMImBF4, EMImSbF6, EMImNbF6, EMImTaF6 and EMImWF7 are liquids at room temperature whereas EMImPF6 and EMImAsF6 melts at around 330 K. Raman spectra of the obtained salts showed the existence of the EMIm cation and corresponding fluorocomplex anions. IR spectroscopy revealed that strong hydrogen bonds are not observed in these salts. EMImAsF6(mp 326 K) and EMImSbF6(mp 283 K) are isostructural with the previously reported EMImPF6. The melting point of the hexafluorocomplex EMIm salt decreases with the increase of the size of the anion (PF6- < AsF6- < SbF6-

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