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1.
Ultrasound Med Biol ; 45(8): 2258-2265, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31153716

RESUMO

We have previously reported a non-invasive method that would be clinically applicable for measurement of speed of sound (SOS) in the liver. The objective of the present study was to confirm the utility of this new method for assessing over time the SOS in liver with progressive steatohepatitis of different grades and stages. Rats were divided into two groups-a control group and a steatohepatitis group-prepared by keeping the rats on a methionine and choline-deficient diet for 43 wk. The SOS through the liver tissue was measured using the new method in comparison with a pulse-receiver as the standard. The SOS through liver with steatohepatitis temporarily decreased with the fat deposition level and then increased in parallel with the progression of inflammation and fibrosis. Monitoring the change in SOS through liver tissue in individual patients with fatty liver would have considerable potential for assisting the non-invasive detection of early-stage steatohepatitis.


Assuntos
Fígado/diagnóstico por imagem , Fígado/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Ultrassonografia/métodos , Animais , Modelos Animais de Doenças , Ratos , Ratos Sprague-Dawley , Som
2.
IJU Case Rep ; 2(5): 245-248, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32743425

RESUMO

INTRODUCTION: Endoscopic retrograde access to the upper urinary tract after Cohen reimplantation for the treatment of vesicoureteral reflux in children is usually difficult. CASE PRESENTATION: We experienced a case involving a few large ureteral stones in the right distal ureter after Cohen reimplantation. We initially failed retrograde access using flexible cystoscope. Therefore, we performed antegrade flexible ureteroscopy through the 10- to 12-Fr access sheath from the middle calyx to treat the few ureteral stones (>1.5 cm) in the right ureter with the patient in the modified Valdivia position. This one-stage procedure was successful. The patient achieved a stone-free status without major complications. CONCLUSION: The herein-described approach that was implemented after Cohen reimplantation was successful. We believe that recent endourologic developments contributed to the good outcome in this case.

3.
Carbohydr Res ; 417: 78-80, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26432611

RESUMO

IF5-pyridine-HF, an air- and moisture-stable fluorinating reagent, was applied to the synthesis of glycosyl fluorides from (phenylthio)glycosides. Common protecting groups of alcohol and diol can tolerate the reaction conditions performed, and therefore, the present method is applicable to the synthesis of various glycosyl fluorides.


Assuntos
Fluoretos/síntese química , Piridinas/química , Tioglicosídeos/síntese química , Halogenação , Estrutura Molecular , Compostos de Sulfidrila/química
4.
Ultrasound Med Biol ; 40(10): 2499-507, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25130448

RESUMO

The speed of sound correlates well with the fat content of the liver. Therefore, non-invasive quantification of sound speed in the liver might be of diagnostic value. Here we describe a new non-invasive method that would be clinically applicable for measurement of sound speed in the liver. Sprague-Dawley rats were divided into two groups: a control group and a fatty liver group prepared by keeping the rats on a choline-deficient diet for 6 wk. The livers were subjected to pathologic and biochemical analysis; the speed of sound through the liver tissue was measured using our proposed method and a pulser-receiver as standard. Our results indicated that use of the proposed method makes it feasible to diagnose fatty liver with good accuracy on the basis of sound speed. This approach would have considerable potential for non-invasive diagnosis of fatty liver and would be a valuable adjunct to conventional liver diagnostic procedures.


Assuntos
Fígado Gorduroso/diagnóstico por imagem , Animais , Deficiência de Colina , Modelos Animais de Doenças , Ratos , Ratos Sprague-Dawley , Processamento de Sinais Assistido por Computador , Ultrassonografia
5.
J Org Chem ; 78(21): 10853-9, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24102624

RESUMO

Direct α-allylation of α-branched aldehydes was successfully carried out with a readily available allyl ester by combined use of two catalytic systems: Tsuji-Trost allylation reaction with an achiral palladium complex and enamine catalysis with a chiral primary α-amino acid. A quaternary carbon stereogenic center was constructed stereoselectively to give various 2,2-disubstituted pent-4-enals in good yields with high enantioselectivity.


Assuntos
Aldeídos/química , Compostos Alílicos/química , Compostos Organometálicos/química , Paládio/química , Aminoácidos , Catálise , Estrutura Molecular , Estereoisomerismo
6.
Org Biomol Chem ; 10(27): 5289-97, 2012 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-22678163

RESUMO

Michael addition reaction of α-branched aldehydes to ß-nitroacrylates was successfully carried out by using a mixed catalyst consisting of a primary amino acid, L-phenylalanine, and its lithium salt to give ß-formyl-ß'-nitroesters having a quaternary carbon centre in good yields (up to 85%) with high enantioselectivity (up to 98% ee). By using benzyl ß-nitroacrylates as Michael acceptors, the obtained ß-formyl-ß'-nitroesters were converted into various 4,4-disubstituted pyrrolidine-3-carboxylic acids including analogues of gabapentin (Neurotin(®)) in one step from the Michael adducts in high yields.

7.
Top Curr Chem ; 327: 59-86, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22527404

RESUMO

Recent developments in the stereoselective synthesis of fluoroalkenes, which include hydrofluorination of alkyne, fluorination of alkenylmetal, condensation methods, dehydrofluorination of gem-difluoro compounds, and a cross-coupling reaction using fluorohaloalkenes or fluoroalkenylmetal, are described in this chapter.


Assuntos
Alcenos/síntese química , Hidrocarbonetos Fluorados/síntese química , Estrutura Molecular , Estereoisomerismo
8.
J Org Chem ; 76(20): 8513-7, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-21894973

RESUMO

Highly enantioselective Michael addition of malonates to enones was achieved using a mixed catalyst consisting of a primary ß-amino acid, O-TBDPS (S)-ß-homoserine, and its lithium salt. Various cyclic and acyclic enones were converted into 1,5-ketoesters in high yields (up to 92%) with high enantioselectivity (up to 97% ee) under mild reaction conditions. Details of synthesis of the catalyst, optimization of the reaction conditions for the Michael addition reaction, and a plausible reaction mechanism are described.


Assuntos
Produtos Biológicos/síntese química , Química Farmacêutica/métodos , Cetonas/química , Malonatos/química , Catálise , Homosserina/química , Lítio/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos de Organossilício/química , Sais/química , Estereoisomerismo
9.
Chem Commun (Camb) ; 47(32): 9191-3, 2011 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21748198

RESUMO

An MT-sulfone group was converted to a trifluoromethyl group by treatment with IF(5) after an alkylation reaction. Therefore, an MT-sulfone anion can be used as a trifluoromethyl anion equivalent. The formal asymmetric Michael-addition of a trifluoromethyl anion to crotonaldehyde was also performed.

10.
J Org Chem ; 76(7): 2305-9, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21388203

RESUMO

One-pot asymmetric synthesis of γ-nitroaldehydes from aldehydes and nitroalkanes was achieved by a catalytic tandem reaction using a primary amino acid lithium salt, O-tert-butyldiphenylsilyl l-tyrosine lithium salt, as a catalyst. Various aryl, alkenyl, and alkyl aldehydes were converted into γ-nitroaldehydes via in situ generation of nitroalkenes.


Assuntos
Aldeídos/química , Alcanos/química , Alcenos/química , Aminoácidos/química , Lítio/química , Nitrocompostos/química , Catálise , Estrutura Molecular , Sais/química , Estereoisomerismo
11.
J Org Chem ; 75(21): 7393-9, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-20936799

RESUMO

The polyfluorination of α-(arylthio)carbonyl compounds was achieved by a successive application of polyfluorination using IF(5), Friedel-Crafts arylation, and desulfurizing fluorination using IF(5). Three to six fluorine atoms were selectively introduced to the carbons located between the aromatic ring and the carbonyl group.

12.
Org Biomol Chem ; 8(13): 3031-6, 2010 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-20461274

RESUMO

Enantioselective Michael addition of aldehydes to nitroalkenes was successfully carried out by asymmetric catalysis with L-phenylalanine lithium salt, giving gamma-nitroaldehydes in good yields with high enantioselectivity.


Assuntos
Aldeídos/química , Alcenos/química , Aminoácidos/química , Lítio/química , Catálise , Sais/química
13.
Chem Commun (Camb) ; (46): 6242-4, 2008 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-19082133

RESUMO

Phenylalanine lithium salt was found to be an effective catalyst for asymmetric Michael addition of isobutyraldehyde with beta-nitroalkenes to give quaternary carbon-containing nitroalkanes.


Assuntos
Aldeídos/química , Alcenos/química , Aminoácidos/química , Lítio/química , Nitrocompostos/química , Sais/química , Catálise , Estrutura Molecular , Transição de Fase , Solventes , Estereoisomerismo
14.
J Org Chem ; 73(11): 4186-9, 2008 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-18459815

RESUMO

Selective fluorination of adamantanes was achieved by the electrochemical fluorination method, using Et 3N-5HF as electrolyte and a fluorine source. Mono-, di-, tri-, and tetrafluoroadamantanes were selectively prepared from adamantanes by controlling the oxidation potential, and the fluorine atoms were introduced selectively at the tertiary carbons. Adamantanes that have functional groups such as ester, cyano, and acetoxymethyl were also fluorinated selectively.


Assuntos
Adamantano/química , Eletroquímica/métodos , Flúor/química , Espectroscopia de Ressonância Magnética , Oxirredução , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho
15.
Appl Environ Microbiol ; 74(2): 352-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18024680

RESUMO

Three bacteria capable of utilizing bis(4-hydroxyphenyl)methane (bisphenol F [BPF]) as the sole carbon source were isolated from river water, and they all belonged to the family Sphingomonadaceae. One of the isolates, designated Sphingobium yanoikuyae strain FM-2, at an initial cell density of 0.01 (optical density at 600 nm) completely degraded 0.5 mM BPF within 9 h without any lag period under inductive conditions. Degradation assays of various bisphenols revealed that the BPF-metabolizing system of strain FM-2 was effective only on the limited range of bisphenols consisting of two phenolic rings joined together through a bridging carbon without any methyl substitution on the rings or on the bridging structure. A BPF biodegradation pathway was proposed on the basis of metabolite production patterns and identification of the metabolites. The initial step of BPF biodegradation involves hydroxylation of the bridging carbon to form bis(4-hydroxyphenyl)methanol, followed by oxidation to 4,4'-dihydroxybenzophenone. The 4,4'-dihydroxybenzophenone appears to be further oxidized by the Baeyer-Villiger reaction to 4-hydroxyphenyl 4-hydroxybenzoate, which is then cleaved by oxidation to form 4-hydroxybenzoate and 1,4-hydroquinone. Both of the resultant simple aromatic compounds are mineralized.


Assuntos
Compostos Benzidrílicos/metabolismo , Água Doce/microbiologia , Sphingomonadaceae/metabolismo , Compostos Benzidrílicos/química , Biodegradação Ambiental , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Modelos Biológicos , Dados de Sequência Molecular , Estrutura Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação
16.
J Org Chem ; 72(25): 9617-21, 2007 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-17979292

RESUMO

(E)- and (Z)-(fluoroalkenyl)boronates were prepared stereospecifically by the reaction of 2-fluoroalkylideneiodonium ylide generated from (E)- or (Z)-(2-fluoroalkenyl)iodonium salts with di(p-fluorophenoxy)alkylboranes, followed by transesterification to pinacol esters. The resulting pinacol esters of (fluoroalkenyl)boranes were used for the stereoselective synthesis of trisubstituted fluoroalkenes by cross-coupling reactions.


Assuntos
Alcenos/química , Ácidos Borônicos/síntese química , Iodo/química , Oniocompostos/química , Boratos , Ácidos Bóricos/química , Ácidos Borônicos/química , Estrutura Molecular , Sais/química , Estereoisomerismo
17.
Org Lett ; 8(12): 2639-41, 2006 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-16737333

RESUMO

Alkylidene-type carbenoids, generated from (Z)- or (E)-(2-fluoro-1-alkenyl)iodonium salts by treatment with LDA, reacted with trialkylboranes to give (E)- or (Z)-(fluoroalkenyl)boranes stereoselectively. The resulting (fluoroalkenyl)borane can be used for the selective synthesis of (E)- or (Z)-fluoroalkenes, (E)- or (Z)-fluoroiodoalkenes, and alpha-fluoroketones. [reaction: see text]

18.
Chem Commun (Camb) ; (28): 3589-90, 2005 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-16010333

RESUMO

Selective monofluorination of 1,2- and 1,3-diols was achieved by reaction with DFMBA. The method is applicable for the synthesis of optically-active fluorohydrin derivatives.

19.
Molecules ; 10(1): 183-9, 2005 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-18007285

RESUMO

Stereoselective synthesis of 5-7 membered cyclic ethers was achieved by deiodonative ring-enlargement of cyclic ethers having an iodoalkyl substituent. The reaction took place readily under mild conditions using hypervalent iodine compounds and an acetoxy or a trifluoroacetoxy group was introduced into the rings depending on the hypervalent iodine reagent employed. The use of hexafluoroisopropanol (HFIP) as solvent is critical.


Assuntos
Éteres Cíclicos/química , Indicadores e Reagentes/farmacologia , Iodo/química , Ciclização , Indicadores e Reagentes/química , Modelos Biológicos , Conformação Molecular
20.
Int J Urol ; 12(12): 1022-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16409603

RESUMO

OBJECTIVES: In order to evaluate the indication and usefulness of laparoscopic adrenalectomy, clinical outcomes of laparoscopic adrenalectomy for patients with adrenal tumors were examined. Whether tumor size affects surgical outcome was analysed, along with the long-term clinical outcome for these patients. PATIENTS AND METHODS: A total of 63 patients with adrenal tumor underwent laparoscopic adrenalectomy in our institute between 1999 and 2003. A laparoscopic transperitoneal approach was used in all cases. Underlying pathologies comprised Cushing syndrome (n = 12), pheochromocytoma (n = 13), primary aldosteronism (n = 21), non-functioning adenoma (n = 12) and others (n = 5). RESULTS: No open conversion was performed. Mean operative duration was 239 min, and mean estimated blood loss was 134 mL. Tumor diameter was significantly smaller for primary aldosteronism than for Cushing syndrome, which in turn was significantly smaller than for adrenocorticotropic hormone-independent macronodular hyperplasia (AIMAH). No significant differences in surgical outcome and postoperative recovery were noted between large (>or=5 cm) and small (<5 cm) tumors. Long-term clinical outcome was better for patients with pheochromocytoma or primary aldosteronism than for patients with Cushing syndrome. CONCLUSIONS: Laparoscopic adrenalectomy for benign tumor offers excellent surgical outcomes and convalescence. This is true for both small and large tumors.


Assuntos
Neoplasias das Glândulas Suprarrenais/patologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Laparoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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