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1.
Opt Express ; 25(15): 17753-17766, 2017 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-28789267

RESUMO

We demonstrate for the first time an efficient, photonic-based astronomical spectrograph on the 8-m Subaru Telescope. An extreme adaptive optics system is combined with pupil apodiziation optics to efficiently inject light directly into a single-mode fiber, which feeds a compact cross-dispersed spectrograph based on array waveguide grating technology. The instrument currently offers a throughput of 5% from sky-to-detector which we outline could easily be upgraded to ∼ 13% (assuming a coupling efficiency of 50%). The isolated spectrograph throughput from the single-mode fiber to detector was 42% at 1550 nm. The coupling efficiency into the single-mode fiber was limited by the achievable Strehl ratio on a given night. A coupling efficiency of 47% has been achieved with ∼ 60% Strehl ratio on-sky to date. Improvements to the adaptive optics system will enable 90% Strehl ratio and a coupling of up to 67% eventually. This work demonstrates that the unique combination of advanced technologies enables the realization of a compact and highly efficient spectrograph, setting a precedent for future instrument design on very-large and extremely-large telescopes.

2.
Rev Sci Instrum ; 93(7): 075109, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35922321

RESUMO

Imaging-based detection of the motion of levitated nanoparticles complements a widely used interferometric detection method, providing a precise and robust way to estimate the position of the particle. Here, we demonstrate a camera-based feedback cooling scheme for a charged nanoparticle levitated in a linear Paul trap. The nanoparticle levitated in vacuum was imaged using a complementary metal-oxide semiconductor (CMOS) camera system. The images were processed in real-time with a microcontroller integrated with a CMOS image sensor. The phase-delayed position signal was fed back to one of the trap electrodes, resulting in cooling by velocity damping. Our study provides a simple and versatile approach applicable for the control of low-frequency mechanical oscillators.

3.
Opt Express ; 17(1): 46-54, 2009 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-19129871

RESUMO

Intense ultrashort light pulses induce three dimensional localized phase transformation of diamond. Photoinduced amorphous structures have electrical conducting properties of a maximum of 64 S/m based on a localized transition from sp(3) to sp(2) in diamond. The laser parameters of fluence and scanning speed affect the resultant electrical conductivities due to recrystallization and multi-filamentation phenomena. We demonstrate that the laser-processed diamond with the periodic cylinder arrays have the characteristic transmission properties in terahertz region, which are good agreement with theoretical calculations. The fabricated periodic structures act as metallo-dielectric photonic crystal.


Assuntos
Diamante , Condutividade Elétrica , Cristalização , Cristalografia , Cinética , Lasers , Luz , Modelos Teóricos , Nanotubos de Carbono , Distribuição Normal , Óptica e Fotônica , Espalhamento de Radiação , Propriedades de Superfície , Raios X
4.
Biochem Pharmacol ; 57(2): 219-23, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9890571

RESUMO

The relationship of ethanol elimination kinetics in mammals was estimated using the allometric principle. The hypothesis of relationships between parameters obtained from the compartment model with Michaelis-Menten elimination kinetics and body weight can lead to common equations of blood ethanol elimination in mammals. The maximum elimination velocity (g/hr) and the apparent volume of distribution (L) were significantly proportional to the 0.71 and 0.93 powers of body weight (r = 0.994, P < 0.01 and r = 0.998, P < 0.001), respectively. There was no significant relationship between the Michaelis constant and body weight. In the differential equations of the two-compartment model, the kinetics parameters were substituted for the obtained power functions. Good fitting of these equations for the real data showed that ethanol elimination kinetics in mammals can be predicted quantitatively.


Assuntos
Simulação por Computador , Etanol/sangue , Modelos Estatísticos , Humanos , Cinética , Especificidade da Espécie
5.
Mutat Res ; 471(1-2): 1-6, 2000 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11080655

RESUMO

Effect of sugars added to ground beef on the generation of mutagenicity of cooked hamburger was investigated. Mutagenicity of hamburger was assayed by the Ames test using Salmonella typhimurium TA98 strain with metabolic activation after the mutagens were purified by use of blue rayon. Intrinsic reducing sugar content in ground beef was estimated to be 0.07% (w/w). Mutagenicity of hamburger was sharply or delicately controlled by the amount of a reducing sugar added to ground beef. Mutagenicity was increased more than 2-folds by addition of 0.08% (w/w) glucose, fructose or lactose but decreased to about a half by addition of more than 0.67% (w/w) each of the reducing sugars. Mutagenicity of cooked hamburger was not influenced by addition of sucrose at the ranges between 0.08 and 0.67% (w/w). When red wine with 0.10% (w/w) equivalent amount of reducing sugars or white wine with 0.13% (w/w) equivalent amount of reducing sugars were added to the ground beef, mutagenicity of cooked hamburger was similarly increased 1.6-1.8-fold. Controlling the reducing sugar content in ground beef would be a simple way to regulate the mutagenicity of cooked hamburgers.


Assuntos
Produtos da Carne/toxicidade , Mutagênicos/toxicidade , Animais , Bovinos , Interações Medicamentosas , Frutose/metabolismo , Frutose/farmacologia , Glucose/metabolismo , Glucose/farmacologia , Temperatura Alta , Lactose/metabolismo , Lactose/farmacologia , Produtos da Carne/análise , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Testes de Mutagenicidade , Mutagênicos/isolamento & purificação , Mutagênicos/metabolismo , Substâncias Redutoras/isolamento & purificação , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Sacarose/metabolismo , Sacarose/farmacologia , Vinho/análise
6.
Mutat Res ; 420(1-3): 109-14, 1998 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-9838070

RESUMO

Addition of onion effectively reduced mutagenicity of cooked hamburger when tested on Salmonella typhimurium TA98 strain with metabolic activation. The components of onion that participated in the reduction of mutagenicity were sugars. Addition of starch or glucose to ground beef the amount equivalent to that in onion reduced the mutagenicity of cooked hamburger. Addition of onion may cause imbalance of the sugar content of ground beef that effectively produces mutagenicity. Mutagenicity of the heated model mixture of glucose/glycine/creatinine in diethyleneglycol-water was reduced by an excessive amount of glucose. Hence, Japanese cooking-style with addition of onion can reduce mutagenicity of hamburger.


Assuntos
Produtos da Carne/toxicidade , Mutagênicos/toxicidade , Cebolas/metabolismo , Animais , Carboidratos/análise , Bovinos , Creatinina/farmacologia , Glucose/farmacologia , Glicina/farmacologia , Testes de Mutagenicidade , Cebolas/química , Salmonella typhimurium/genética
7.
Acta Otolaryngol ; 93(1-6): 227-32, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7199807

RESUMO

Cisplatin was administered to guinea pigs. Hearing function was tested using ABR, and morphological studies were conducted by scanning and transmission electron microscopy. The following findings were made. (1) The susceptibility to cochlear damage by cisplatin was dose dependent. (2) At the same dose, damage was most severe in the lower turns, particularly in the second turn. This tallies with the high tone loss. (3) Mainly the outer hair cells are the site of the damage and the inner hair cells are rarely damaged. (4) The first row of the outer hair cells tend to be more severely damaged. (5) Variation of the stria vascularis was moderate compared with the damage to the organ of Corti. (6) A tendency of recovery was observed in ABR in some animals after they were given 2 mg/kg/day cisplatin intramuscularly consecutively for 8 days.


Assuntos
Cisplatino/farmacologia , Cóclea/efeitos dos fármacos , Animais , Tronco Encefálico/fisiologia , Relação Dose-Resposta a Droga , Potenciais Evocados Auditivos/efeitos dos fármacos , Cobaias , Células Ciliadas Auditivas/efeitos dos fármacos , Células Ciliadas Auditivas/ultraestrutura , Órgão Espiral/efeitos dos fármacos , Órgão Espiral/ultraestrutura , Estria Vascular/efeitos dos fármacos , Estria Vascular/ultraestrutura
8.
Acta Otolaryngol ; 94(1-2): 37-43, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7124389

RESUMO

In a series of animal experiments on guinea pigs and rats, conducted in an attempt to find a better solution for the treatment of sensorineural hearing impairment and tinnitus-known as diseases almost impossible to heal-it was revealed electrophysiologically, biochemically and electronmicroscopically that loop diuretics, referred to as ototoxic drugs, cause an increased amount of the therapeutic preparation to transfer to the inner ear fluid. It is concluded, on the basis of the encouraging results of these experiments, that combined medication with metabolic activator, steroid hormone and loop diuretics is significantly more effective in improving the symptoms of patients with inner ear deafness and tinnitus.


Assuntos
Furosemida/uso terapêutico , Perda Auditiva Neurossensorial/tratamento farmacológico , Animais , Cobaias , Perda Auditiva Neurossensorial/induzido quimicamente , Canamicina , Líquidos Labirínticos , Ratos , Ratos Endogâmicos
9.
Radiat Med ; 15(2): 79-83, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9192431

RESUMO

We evaluated the usefulness of low-dose Ga-67 scintigraphy as a diagnostic tool for the detection of non-Hodgkin's lymphoma recurrence. Forty-six patients were included in this retrospective study. Anterior and posterior whole body images were obtained two or three days after the injection of 74 MBq of Ga-67. Inter- and intraobserver variability in scintigraphic imaging interpretation was analyzed using the kappa (kappa) statistics. Ga-67 scintigraphy allowed correct detection of recurrence in 18 of 22 events (sensitivity, 82%), and excluded relapse in 34 of 39 events (specificity, 87%). The positive predictive value was 0.78 and negative predictive value 0.89. All cases involving superficial lymph nodes (10/ 10) could be detected by Ga-67. Chest lesions were diagnosed with a sensitivity of 86% (6/7), bone and soft tissue 83% (5/6), and abdomen 80% (8/10). The sensitivity and specificity of CT were 91% (22/24) and 67% (8/12), respectively. In abdominal lesions, ultrasonography had sensitivity and specificity of 93% (14/15) and 94% (15/16), respectively. Kappa (kappa) statistics demonstrated good to strong inter- and intraobserver agreement in the interpretation of Ga-67 scintigraphy. The diagnostic results of low-dose Ga-67 scans, currently applied in Japan, were similar to those reported by the authors using high doses of 296 MBq to 370 MBq. Ga-67 scintigraphy, even at low dose, is useful in the detection of non-Hodgkin's lymphoma recurrence.


Assuntos
Radioisótopos de Gálio , Linfoma não Hodgkin/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Adulto , Idoso , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Cintilografia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Ultrassonografia
10.
Nihon Hoigaku Zasshi ; 51(5): 401-5, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9436369

RESUMO

A 25-year-old male was killed with a survival knife by his business and homosexual partner. In addition to 22 wounds on the extremities, 16 wounds were found on the neck, chest and abdomen. The heart and lungs were penetrated, and three wound tracks reached the back of the body. The cause of death was diagnosed as hemorrhage. The genitalia of the victim was anomalous: the pubic hair pattern was that of a female, the penis was small and no testes were identified in the scrotal sac. According to his medical records, micropenis and bilateral cryptorchidism were present at birth, and neither hormonal treatments nor bilateral orchidopexy could enlarge his penis size. At the age of 17, his condition had been diagnosed as hypergonadotropic hypogonadism. His genital anomalies were considered due to embryonic testicular regression syndrome, and his micropenis a possible cause of his homosexual orientation. Judging from the patulous anus with thickened margins, he was probably a passive homosexual. The motive of the murder was not monetary, but rather emotional entanglement. The court judged that the case was one of premeditated murder with a short-circuited motive, and sentenced the defendant to ten years imprisonment.


Assuntos
Criptorquidismo/complicações , Homicídio , Homossexualidade Masculina , Testículo/anormalidades , Adulto , Humanos , Masculino
11.
Nihon Hoigaku Zasshi ; 51(6): 438-41, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9545758

RESUMO

The cause of death in a 45-day-old male infant who was found apneic at home and died 21 hours later was disseminated intravascular coagulation (DIC). The patient was admitted to a hospital in a state of cardio-respiratory arrest. The initial diagnosis was interrupted sudden infant death syndrome. The patient remained apneic, and recurrent discharge of bloody stool was the dominant clinical findings. He died without spontaneous respiration being restored. The autopsy revealed hemorrhages in the lungs and the ventricular septum and the free wall of the left ventricle of the heart. Microscopically, fibrin thrombi were noted in the large intestine and heart. The DIC was probably triggered by a widespread endothelial injury caused by severe hypoxia and acidosis originating from the apnea and cardiac arrest lasting longer than 30 min.


Assuntos
Coagulação Intravascular Disseminada/patologia , Medicina Legal , Morte Súbita do Lactente/patologia , Humanos , Lactente , Masculino , Trombose/patologia
13.
Pulm Pharmacol Ther ; 15(4): 363-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12220941

RESUMO

We previously showed that inhaled furosemide improves experimentally induced dyspnea. In order to test the possibility that inhaled furosemide may alter the CO(2) chemosensitivity and thereby reduce the dyspneic sensation, the effect of inhaled furosemide on CO(2) chemosensitivity was evaluated with a double-blinded, randomized crossover design in 10 healthy subjects. The CO(2) chemosensitivity was measured by the steady-state and rebreathing methods before and after the inhalation of placebo (normal saline) and furosemide aerosols (40 mg). In addition, subjects were asked to rate their sensation of respiratory discomfort using a visual analog scale (dyspneic VAS) during the measurement of CO(2) chemosensitivity with the steady-state method. Our results showed that (1) inhaled furosemide does not affect the breathing patterns of resting breathing, (2) inhaled furosemide does not affect the slope and intercept of the CO(2) response curve, regardless of whether the CO(2) chemosensitivity is measured by the steady-state technique or rebreathing technique and (3) inhaled furosemide improves the dyspneic sensation produced during hypercapnic hyperpnea. These results suggest that the mechanism of the improvement of dyspnea by inhaling furosemide is not associated with the decrease in the ventilatory drive to CO(2).


Assuntos
Dióxido de Carbono/fisiologia , Diuréticos/farmacologia , Furosemida/farmacologia , Ventilação Pulmonar/efeitos dos fármacos , Administração por Inalação , Adulto , Células Quimiorreceptoras/efeitos dos fármacos , Células Quimiorreceptoras/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Dispneia/tratamento farmacológico , Feminino , Humanos , Hipercapnia/fisiopatologia , Masculino , Ventilação Pulmonar/fisiologia , Descanso
14.
Arch Otorhinolaryngol ; 238(3): 273-9, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6651610

RESUMO

Ferritin transport through the strial capillary during kanamycin intoxication was examined under a transmission electron microscope. Twelve guinea pigs were treated intramuscularly with kanamycin (400 mg/kg/day) for 2-3 weeks. When full hearing loss was recognized by estimating the Preyer reflex or auditory brain-stem response (ABR), ferritin was given intravenously and animals were sacrificed 1/3, 1, and 2 h later. At 1/3 h, ferritin was present diffusely not only in the endothelial cell but also in the basal lamina and within vesicles in the strial cell. Alternatively, it was discharged into the endolymphatic space. At 2 h, ferritin was seen on the luminal surface and in the cytoplasm of the endolymphatic cells of Reissner's membrane. These results suggest that the basal lamina of the strial capillary was altered qualitatively by kanamycin administration.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Cóclea/fisiologia , Canamicina/farmacologia , Estria Vascular/fisiologia , Animais , Transporte Biológico/efeitos dos fármacos , Ferritinas/metabolismo , Cobaias , Microscopia Eletrônica , Estria Vascular/efeitos dos fármacos , Estria Vascular/ultraestrutura
15.
Alcohol Alcohol ; 35(1): 31-4, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10684773

RESUMO

The objective of this study was to elucidate the role of Kupffer cells during the increase of portal vein pressure caused by ethanol. We measured nitric oxide (NO) in the perfused rat liver using a commercial NO meter. Ethanol perfusion increased NO release and portal vein pressure. Gadolinium chloride pretreatment reduced the increase in portal vein pressure during the early phase of ethanol perfusion, but did not affect the release of NO after ethanol infusion. These findings suggest that Kupffer cells play an important role in liver microcirculation during the early stage of ethanol intake, but that the mechanism may not be regulated by NO.


Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Células de Kupffer/efeitos dos fármacos , Fígado/efeitos dos fármacos , Óxido Nítrico/metabolismo , Pressão na Veia Porta/efeitos dos fármacos , Animais , Masculino , Doadores de Óxido Nítrico , Penicilamina/análogos & derivados , Ratos , Ratos Wistar
16.
Acta Otolaryngol Suppl ; 486: 66-72, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1842880

RESUMO

Evoked otoacoustic emissions (EOEs) were examined in ears with idiopathic sudden deafness (ISD) at an early stage after onset and were compared with those in ears with long-standing sensorineural hearing losses of unknown etiology (SHLUE). In ears with SHLUE, EOEs were not recordable from ears with a hearing loss exceeding 35 dB at minimum hearing level of 4 audiometric frequencies: 500, 1,000, 2,000 and 4,000 Hz (4 MHL). On the other hand, although 4 MHLs were greater than 35 dB in most of the ears, EOEs could be detected in about one-half of the ears with ISD, and, moreover, the majority of these EOE detectable ears showed a good hearing prognosis in spite of the degree of hearing loss. There was, however, no correlation between EOE threshold and degree of hearing recovery. From these results it seems that EOE testing might be clinically applicable for predicting whether or not hearing loss due to ISD can be recovered.


Assuntos
Perda Auditiva Súbita/fisiopatologia , Estimulação Acústica , Potenciais Evocados Auditivos , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Súbita/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Emissões Otoacústicas Espontâneas/fisiologia , Prognóstico
17.
Acta Otolaryngol Suppl ; 486: 73-7, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1842882

RESUMO

Evoked otoacoustic emissions (EOEs) were examined in 8 normal hearing ears without spontaneous otoacoustic emissions (SOEs), and the frequency of the first 10 ms after appearance of the EOE response wave was analyzed, dividing it into the first 5 ms half (First half A) and the last 5 ms half (Last half B). In the First half A, the peak frequency of the power spectrum tended to match the stimulus frequency, but in the Last half B, the peak frequency tended to be constant and moreover, it tended to match the frequency at which EOE can best be recorded. These findings suggest that each ear has its own characteristic EOE frequency.


Assuntos
Cóclea/fisiologia , Potenciais Evocados Auditivos/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Humanos , Processamento de Sinais Assistido por Computador
18.
Acta Otolaryngol Suppl ; 397: 49-59, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6314736

RESUMO

It is known that beta-adrenergic stimulants enhance mucociliary transport in the respiratory tract. The present study clearly indicated that such an enhancement resulted from not only the alteration in secretory function but also the direct stimulation of ciliated cells. However, the enhancement of ciliary beating depended on the morphological changes in ciliated cells. On the other hand, the effect of terbutaline aerosol, a beta-adrenergic stimulant, on patients with chronic sinusitis was evaluated by paranasal sinus radiography. Consequently, marked improvements in shadows were achieved after 4 weeks in 40% of the cases examined.


Assuntos
Cílios/efeitos dos fármacos , Transtornos da Motilidade Ciliar/tratamento farmacológico , Sinusite/tratamento farmacológico , Terbutalina/uso terapêutico , Adulto , Aerossóis , Animais , Criança , Doença Crônica , Feminino , Humanos , Masculino , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/efeitos dos fármacos , Pessoa de Meia-Idade , Coelhos , Radiografia , Sinusite/diagnóstico por imagem
19.
Nihon Igaku Hoshasen Gakkai Zasshi ; 56(14): 1056-60, 1996 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-9014468

RESUMO

PURPOSE: Radiation therapy is a useful palliative modality for refractory lesions of multiple myeloma. It has been reported that total doses of 10 to 20 Gy are usually adequate to obtain some degree of pain relief. However, there are many patients who need additional doses to obtain sufficient pain relief. In this study, we retrospectively analyzed the records of patients with multiple myeloma irradiated at our department, in an attempt to develop an effective treatment policy for this disease. MATERIALS AND METHODS: Twenty-nine patients with 53 lesions were treated between 1968 and 1993. Total irradiation doses were 4 to 60 Gy(median 40 Gy) with daily fractions of 2 Gy or less, and 16 to 51 Gy(median 30 Gy) with daily fractions greater than 2 Gy. Evaluated were 59 symptoms, including pain (68%), neurological abnormalities (15%), and masses (28%). RESULTS: Symptomatic remission was obtained in 33 of 36 (92%) lesions with pain, 6 of 8(75%) with neurological abnormalities, and 13 of 15(87%) mass lesions. Pain was partially relieved at a median TDF of 34, and completely at a median TDF of 66(equivalent to 40-42 Gy with daily fractions of 2 Gy). CONCLUSIONS: Radiation therapy is an effective and palliative treatment method for symptomatic multiple myeloma. However, the treatment seems to require higher radiation doses than those reported to obtain adequate relief of symptoms.


Assuntos
Mieloma Múltiplo/radioterapia , Cuidados Paliativos , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Intratável/radioterapia , Radioterapia de Alta Energia
20.
J Biol Chem ; 265(32): 19898-903, 1990 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-2246266

RESUMO

An acid proteinase was purified to apparent homogeneity from the plasmodia of a slime mold, Physarum polycephalum, by a combination of detergent extraction, acid precipitation, and column chromatographies on DEAE-Sephadex, hydroxylapatite, CM-Sephadex, and Sephadex G-100. The enzyme was shown to be composed of two polypeptide chains (a 31-kDa heavy chain and a 23-kDa light chain) cross-linked by disulfide bond(s). The NH2-terminal amino acid sequence of the heavy chain was determined to be Ala-Gly-Val- Asp-Gly-Tyr-Ile-Val-Pro-Tyr-Val-Ile-Phe-Asp-Leu-Tyr-Gly-Ile-Pro-Tyr and that of the light chain to be Ala-Glu-Pro-Pro-Ile. The heavy chain contained carbohydrate moiety composed of mannose, glucosamine, fucose, and glucose. The enzyme was optimally active at pH 1.7 toward hemoglobin as a substrate. Among the proteinase inhibitors tested only diazoacetyl-D,L-norleucine methyl ester, a typical aspartic proteinase inhibitor, inhibited the acid proteinase in the presence of cupric ions. It was insensitive to the other typical aspartic proteinase inhibitors, pepstatin A and 1,2-epoxy-3-(p-nitrophenoxy)propane. The enzyme hydrolyzed Lys-Pro-Ile-Glu-Phe(4-NO2)-Arg-Leu at the Phe-Phe(4-NO2) bond, but could not hydrolyze another synthetic pepsin-substrate, N-acetyl-L-phenylalanyl-3,5-diiodo-L-tyrosine. The enzyme showed a unique substrate specificity toward oxidized insulin B chain. The major cleavage sites were the bonds Gly8-Ser9, Leu11-Val12, Cya19-Gly20, and Phe24-Phe25, and the Gly8-Ser9 bond was most susceptible. These results indicate that the enzyme is a novel type of intracellular acid proteinase with a unique substrate specificity.


Assuntos
Endopeptidases/isolamento & purificação , Physarum/enzimologia , Sequência de Aminoácidos , Aminoácidos/análise , Carboidratos/análise , Cromatografia , Endopeptidases/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Insulina/metabolismo , Dados de Sequência Molecular , Peso Molecular , Peptídeos/metabolismo , Inibidores de Proteases/farmacologia , Especificidade por Substrato
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