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1.
Phys Rev Lett ; 133(1): 012501, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39042802

RESUMO

To search for low-energy resonant structures in isospin T=3/2 three-body systems, we have performed the experiments ^{3}H(t,^{3}He)3n and ^{3}He(^{3}He,t)3p at intermediate energies. For the 3n experiment, we have newly developed a thick Ti-^{3}H target that has the largest tritium thickness among targets of this type ever made. The 3n experiment for the first time covered the momentum-transfer region as low as 15 MeV/c, which provides ideal conditions for producing fragile systems. However, in the excitation-energy spectra we obtained, we did not observe any distinct peak structures. This is in sharp contrast to tetraneutron spectra. The distributions of the 3n and 3p spectra are found to be similar, except for the displacement in energy due to Coulomb repulsion. Comparisons with theoretical calculations suggest that three-body correlations exist in the 3n and 3p systems, although not enough to produce a resonant peak.

2.
Nano Lett ; 17(5): 2865-2870, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28350468

RESUMO

Constructing quantum devices comprises various challenging tasks, especially when concerning their nanoscale geometry. For quantum color centers, the traditional approach is to fabricate the device structure after the nondeterministic placement of the centers. Reversing this approach, we present the controlled generation of quantum centers in silicon carbide (SiC) by focused proton beam in a noncomplex manner without need for pre- or postirradiation treatment. The generation depth and resolution can be predicted by matching the proton energy to the material's stopping power, and the amount of quantum centers at one specific sample volume is tunable from ensembles of millions to discernible single photon emitters. We identify the generated centers as silicon vacancies through their characteristic magnetic resonance signatures and demonstrate that they possess a long spin-echo coherence time of 42 ± 20 µs at room temperature. Our approach hence enables the fabrication of quantum hybrid nanodevices based on SiC platform, where spin centers are integrated into p-i-n diodes, photonic cavities, and mechanical resonators.

3.
Chem Sci ; 9(13): 3282-3289, 2018 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-29732107

RESUMO

A spontaneous entrapment of electron-donating small guest molecules, including tetrathiafulvalene (TTF) and N,N,N',N'-tetramethyl-1,3-propanediamine (TMPDA), was realized in a structurally flexible metal-organic framework, {Mn7(2,7-AQDC)6(2,6-AQDC)(DMA)6}∞ (AQDC = anthraquinone dicarboxylates, DMA = N,N-dimethylacetamide), with electron-accepting anthraquinone groups, generating two MOF guest charge transfer complexes: {Mn7(2,7-AQDC)6(2,6-AQDC)(DMA)6(TTF)5} and {Mn7(2,7-AQDC)6(2,6-AQDC)(DMA)4(H2O)2(TMPDA)7}. Using a mild impregnation procedure, single crystals of the target complexes were obtained via a crystal-to-crystal conversion, and the crystals were suitable for structural analysis. Single crystal X-ray analysis demonstrated the different arrangements of these intercalated donor molecules: some donor molecules interacted with the anthraquinone groups and formed infinite D-A-A-D stacks, some appeared beside the anthraquinone groups but only formed donor-acceptor pairs, and the remainder of the molecules simply filled the space. The charge transfer between the guests and the framework was spectroscopically confirmed, and the radical densities on the organic species were estimated using magnetic susceptibility measurements. Compared with a solid-state mixture of anthraquinone and donor molecules, the evenly distributed donor molecules in the micropores of the MOF resulted in a "solid solution" state and significantly promoted the degree of charge transfer between donors and acceptors. Such an encapsulation process may be adopted as a new strategy for post-modification of the electronic and magnetic properties of MOFs, as well as for generating new semiconducting charge-transfer complexes.

4.
Leukemia ; 19(6): 1010-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15843825

RESUMO

We previously reported that all-trans retinoic acid (ATRA) inhibits growth in human T-cell leukemia virus type 1 (HTLV-1)-positive T-cell lines and fresh cells from patients with adult T-cell leukemia. However, the mechanism of this inhibition is not clear. In the present study, we observed that NF-kappaB transcriptional activity as well as cell growth decreased significantly in HTLV-1-positive T-cell lines in the presence of ATRA. Furthermore, we observed that ATRA reduced HTLV-1 proviral DNA, HTLV-1 genes (gag, tax, or pol mRNA) using the real-time quantitative polymerase chain reaction. SIL-2R was reduced by ATRA in both protein level (culture supernantant) and mRNA level in HTLV-1-positive T-cell lines. Interestingly, ATRA significantly inhibited RT activity similar to azidothimidine (AZT) in HTLV-1-positive T-cell lines. Moreover, AZT inhibited proviral DNA but not NF-kappaB transcriptional activity, and sIL-2R on HTLV-1; however, ATRA inhibited of NF-kappaB, proviral DNA and sIL-2R on HTLV-1. These results suggested that the decrease in sIL-2R induced by ATRA may be caused by the actions of a NF-kappaB inhibitor acting on the NF-kappaB/sIL-2R signal pathway. These results suggested that ATRA could have two roles, as a NF-kappaB inhibitor and as an RT inhibitor.


Assuntos
Antineoplásicos/farmacologia , Leucemia de Células T/tratamento farmacológico , Leucemia de Células T/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tretinoína/farmacologia , Adulto , Divisão Celular/efeitos dos fármacos , Infecções por Deltaretrovirus/tratamento farmacológico , Infecções por Deltaretrovirus/metabolismo , Infecções por Deltaretrovirus/fisiopatologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Produtos do Gene gag/genética , Produtos do Gene pol/genética , Genes pX/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/crescimento & desenvolvimento , Humanos , Técnicas In Vitro , Células Jurkat , Leucemia de Células T/fisiopatologia , NF-kappa B/metabolismo , Provírus/genética , Receptores de Interleucina-2/metabolismo , Solubilidade , Ativação Transcricional/efeitos dos fármacos , Carga Viral
5.
Chem Commun (Camb) ; 51(64): 12728-31, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26166313

RESUMO

The structure of a glass obtained by the melt quenching of a two-dimensional (2D) coordination network was examined. X-ray analyses disclosed a 2D-to-0D structural transformation before and after glass formation. The mechanism is unique to coordination compounds, as it is characterized by labile and flexible coordination bonds.


Assuntos
Vidro/química , Cristalografia por Raios X , Modelos Moleculares , Conformação Molecular
6.
Ann Clin Biochem ; 36 ( Pt 2): 202-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10370737

RESUMO

We determined the urinary amino acid concentrations by high-performance liquid chromatography (HPLC) using an eluent buffer which had been processed through a column packed with strong cation-exchange resin. With this column, ghost peaks resolved or much reduced in size and shifted to a post-arginine position. A clearer separation of peaks of urinary amino acids and ammonia was obtained. This could be due to the elimination of O-phthalaldehyde reactive substances in the eluent by the resin column. This method does not require a separate step to remove ammonia, unlike most of the methods currently used, and thus saves time.


Assuntos
Aminoácidos/urina , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Asparagina/urina , Ácido Aspártico/urina , Ácido Glutâmico/urina , Glutamina/urina , Humanos , Reprodutibilidade dos Testes
7.
Hepatogastroenterology ; 34(1): 16-8, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3570138

RESUMO

We have measured the plasma concentration of neutral amino acids before and after an oral glucose tolerance test (100 g) in patients with liver cirrhosis (LC), chronic active hepatitis (CAH), chronic persistent hepatitis (CPH), acute hepatitis in the acute stage (AHa) and acute hepatitis in the convalescent stage (AHc) and normal controls. The ratio of the concentration of an amino acid to the sum of those of the other neutral amino acids that compete during transport through the blood brain barrier (BBB), which was reported to correlate well with the brain level of the amino acid, was compared in patients with various liver diseases. The ratios of Trp (Trp/Tyr + Phe + Ile + Leu + Val), Tyr, Phe, and Val increased after glucose loading in all subjects, except Tyr in normal controls, which slightly decreased. On the other hand, Ile and Leu ratios decreased (Trp; tryptophan, Tyr; tyrosine, Phe; phenylalanine, Ile; isoleucine, Leu; leucine, Val; valine). LC showed a characteristic pattern; the ratios of Trp and Tyr were highest among all diseases at 3 hours after glucose loading, and those of Ile, Leu and Val were lowest. We assumed that delta an amino acid ratio = the amino acid ratio at 3 hrs after glucose loading minus the amino acid ratio at 0 hr. In LC, delta Trp ratio and delta Tyr ratio were highest, while delta Val ratio was lowest. The delta Phe ratios in AHa and AHc were significantly higher than those in healthy controls. From these results, the uptake of Trp and Tyr might be supposed to be highest and that of Val was lowest in LC, after glucose loading.


Assuntos
Aminoácidos/sangue , Hepatopatias/sangue , Adulto , Idoso , Barreira Hematoencefálica , Encéfalo/metabolismo , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
8.
Hepatogastroenterology ; 37 Suppl 2: 81-4, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2083940

RESUMO

We examined the level of plasma amino acids, glucose, immunoreactive insulin (IRI) and immunoreactive glucagon (IRG) of patients in the fasted state with acute hepatitis in the actual acute stage (AHa), acute hepatitis in the convalescent stage (AHc), chronic active hepatitis (CAH), chronic persistent hepatitis (CPH) and liver cirrhosis (LC). In AHa patients, the plasma glucose (FPG), plasma alanine (Ala), tryptophan (Trp) and histidine (His) levels were significantly lower and plasma cystine (Cys) level significantly higher than the control levels. This however, was not the case in the other patients. The glutamic acid (Glu) concentration was significantly higher in AHa (p less than 0.02), CAH (p less than 0.001) and CPH (p less than 0.001) and the tyrosine (Tyr) concentration was significantly higher in AHa (p less than 0.02), CPH (p less than 0.001), CAH (p less than 0.001) and LC (p less than 0.001) than they were in the controls. The lysine (Lys) concentration was significantly raised in the AHa (p less than 0.02) and CPH (p less than 0.05) cases. The IRG level was significantly higher in AHa (p less than 0.001), in AHc (p less than 0.01) and LC (p less than 0.01). Valine (Val) showed a significant decrease in concentration in AHa (p less than 0.01) and LC (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aminoácidos/sangue , Jejum/sangue , Hepatopatias/sangue , Adolescente , Adulto , Idoso , Glicemia/análise , Feminino , Glucagon/sangue , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade
9.
Am J Chin Med ; 26(3-4): 375-81, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9862025

RESUMO

Administration of hot water soluble extracts of Ganoderma lucidum (GI) (36 to 72 g dry weight/day) decreased pain dramatically in two patients with postherpetic neuralgia recalcitrant to standard therapy and two other patients with severe pain due to herpes zoster infection.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Herpes Zoster/complicações , Neuralgia/tratamento farmacológico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/etiologia , Dor/tratamento farmacológico , Dor/etiologia , Medição da Dor
10.
Am J Chin Med ; 23(2): 195-211, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7572781

RESUMO

A 34 year-old man with leukemic lymphoblastic lymphoma (LBL), who could not tolerate chemotherapy due to its side effects, was diagnosed to have an acute febrile disease by a traditional Chinese medical doctor, Lu Gan Fu. Zixuedan, a traditional Chinese remedy for dissipation of pathogenic heat and detoxification that could reduce WBC count including leukemic cells below 1000/microliters without intolerable side effects, was prescribed for treatment. A second case of acute lymphocytic leukemia (ALL) was a 41 year-old female who also could not tolerate chemotherapy. In her fourth recurrence, she started Chinese medicine including modified zixuedan, which gave her transient improvement followed by aggravation. Intake of previously ineffective cyclophosphamide in combination with Chinese medicine led to a dramatic improvement.


Assuntos
Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Medicina Tradicional Chinesa , Adulto , Plaquetas/efeitos dos fármacos , Feminino , Hemoglobinas/metabolismo , Humanos , Magnoliopsida , Masculino , Fitoterapia , Fatores de Tempo
13.
Biotherapy ; 11(4): 235-40, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9950099

RESUMO

Administration of hot water extracts of six herbs to four patients with recurrent herpes labialis led to prompt crusting over and complete recovery within a few days. Similar treatment for one female patient who had been suffering from recurrent genital herpes resolved the associated pain dramatically. In all cases mentioned, symptoms disappeared much more quickly than with previous outbreaks when herb extracts were not administered.


Assuntos
Herpes Genital/terapia , Herpes Labial/terapia , Fitoterapia , Adulto , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/uso terapêutico , Reishi
14.
J Clin Chem Clin Biochem ; 23(5): 259-64, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-3894565

RESUMO

Changes in amino acid concentrations in plasma during a 100 g oral glucose tolerance test were investigated in patients with liver cirrhosis and in healthy controls. In the controls, almost all amino acid concentrations reached a nadir about 3 hours after glucose loading, then returned to initial levels after 6 hours. Immunoreactive insulin levels reached a peak about 30 minutes after loading, then decreased gradually, reaching initial levels after 6 hours. In the controls, the decrease ratios, defined as maximum decrease during the 3 hours after loading/initial concentration in plasma, were 0.607 and 0.554 for isoleucine (Ile) and leucine (Leu) respectively and 0.382 for valine (Val) which is significantly lower than for Ile or Leu. A similar tendency was recognized in patients with liver cirrhosis. The initial concentration of tyrosine (Tyr) and phenylalanine (Phe) in liver cirrhosis was significantly higher and their decrease ratios were significantly lower than in controls. Though no difference was observed between initial concentrations of tryptophan (Trp) in controls and liver cirrhosis patients, the decrease ratio of Trp in liver cirrhosis was lower (0.061) than that of controls (0.279) (p less than 0.001). The value, t-Trp/BCAA + AAA, i.e. total Trp concentration (mmol/l)/concentration (mmol/l) of branched chain amino acids (BCAA, Ile + Leu + Val) plus aromatic amino acids (AAA, Tyr + Phe), which is known to correlate with the brain Trp concentration of rats (Fernstrom, J. D. & Wurtman, R. J. (1972) Science 178, 414-416), changed significantly from 9.6 +/- 2.4 (mean +/- 1 SD) at the initiation to 12.9 +/- 3.3 at 3 hours after loading in controls (p less than 0.001), and in liver cirrhosis it changed from 10.3 +/- 1.9 to 15.8 +/- 3.1 (p less than 0.001).


Assuntos
Aminoácidos/sangue , Encefalopatia Hepática/sangue , Adulto , Idoso , Glicemia/metabolismo , Feminino , Glucagon/sangue , Teste de Tolerância a Glucose , Humanos , Verde de Indocianina , Insulina/sangue , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade
15.
J Clin Chem Clin Biochem ; 22(4): 291-9, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6330273

RESUMO

Free tryptophan in plasma was separated by centrifugation through an Amicon ultrafiltration membrane cone. The value obtained without control of pH was found to be lower than that obtained with control of pH by an improved method ( Hijikata et al. (1981) Anal. Biochem. 118, 10-16). For determination of the total tryptophan concentration in the plasma, high performance liquid chromatography (HPLC) was better than the method of Denckla Dewey as modified by Bloxam & Warren ( (1974) Anal. Biochem. 60, 621-625), as judged on the basis of sensitivity, recovery rate and coefficient of variance. The total tryptophan concentration in the plasma determined by HPLC was lower than that determined by the Bloxam & Warren method. The total tryptophan concentration (t-Trp), free tryptophan concentration (f-Trp) and f-Trp/t-Trp ratio were 55.8 +/- 10.2 mumol/l, 11.6 +/- 1.5 mumol/l and 0.211 +/- 0.03 (mean +/- 1 SD) respectively, in healthy subjects (controls). No significant difference was observed between the values of controls and those of patients with liver cirrhosis, hepatocellular carcinoma, liver cirrhosis with hepatocellular carcinoma and hepatic encephalopathy of liver cirrhosis without bleeding. But in liver cirrhosis with bleeding, free tryptophan concentration (f-Trp, 48.0 +/- 23.3 mumol/l, p less than 0.001) and f-Trp/t-Trp ratio (0.645 +/- 0.289, p less than 0.001) were significantly higher than those of controls.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Triptofano/sangue , Aminoácidos/sangue , Carcinoma Hepatocelular/sangue , Cromatografia Líquida de Alta Pressão/métodos , Técnicas de Laboratório Clínico , Hepatite/sangue , Humanos , Cirrose Hepática/sangue , Hepatopatias/diagnóstico , Neoplasias Hepáticas/sangue , Microquímica , Valores de Referência , Ultrafiltração
16.
Jpn Circ J ; 65(3): 139-44, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11266184

RESUMO

Atheroma appears as a very low signal intensity area on 2-dimensional time-of-flight (TOF) magnetic resonance (MR) images, and its components have various signal intensities on spin-echo (SE) images. The present study investigated atheroma of the carotid arteries in 37 subjects with risk factors (63+/-10 years of age; 19 men) by magnetic resonance imaging (MRI). On 2-dimensional (2D) TOF images, the carotid arteries were clearly demonstrated in all cases and atheroma was detected in 23 patients. The most common location of atheroma was at the origin of the internal carotid artery. There was vascular remodeling in all patients with atheroma. 2D-TOF images showed 97% agreement with ultrasonography. SE images clearly demonstrated atheroma in all 23 patients with atheroma. All patients with atheroma showing high signal intensity on T1-weighted images had hyperlipidemia. These findings indicate that the 2D-TOF imaging method is useful for detecting atheroma and SE-images are useful for its characterization.


Assuntos
Arteriosclerose/diagnóstico , Doenças das Artérias Carótidas/diagnóstico , Angiografia por Ressonância Magnética/normas , Idoso , Arteriosclerose/patologia , Doenças Cardiovasculares/diagnóstico , Doenças das Artérias Carótidas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Risco , Ultrassonografia/normas
17.
Jpn Circ J ; 64(10): 760-4, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11059616

RESUMO

In 21 patients with chronic aortic dissections and proven patent false lumens, the flow volume and flow patterns in the patent false lumens was evaluated using velocity-encoded cine magnetic resonance imaging (VENC-MRI) and the relationship between the flow characteristics and aortic enlargement was retrospectively examined. Flow patterns in the false lumen were divided into 3 groups: pattern A with primarily antegrade flow (n=6), pattern R with primarily retrograde flow (n=3), and pattern B with bidirectional flow (n=12). In group A, the rate of flow volume in the false lumen compared to the total flow volume in true and false lumens (%TFV) and the average rate of enlargement of the maximum diameter of the dissected aorta per year (deltaD) were significantly greater than in groups R and B (%TFV: 74.1+/-0.07 vs 15.2+/-0.03 vs 11.8+/-0.04, p<0.01; deltaD: 3.62+/-0.82 vs 0 vs 0.58+/-0.15 mm/year, p<0.05, respectively). There was a significant correlation between %TFV and deltaD (r=0.79, p<0.0001). Evaluation of flow volume and flow patterns in the patent false lumen using VENC-MRI may be useful for predicting enlargement of the dissected aorta.


Assuntos
Aneurisma Aórtico/fisiopatologia , Dissecção Aórtica/fisiopatologia , Imagem Cinética por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Estudos Retrospectivos
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