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1.
J Phys Chem A ; 128(13): 2672-2679, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38530789

RESUMO

Photoemission orbital tomography (POT) from photoelectron momentum maps (PMMs) is a powerful technique that visualizes the shape of the molecular orbitals (MOs) of molecular films. For further utilization of POT, a simple and low-cost method of POT is highly required. Here, we propose a new POT method based on the PhaseLift algorithm (PhaseLift POT). This method utilizes a lifting procedure to convert the PMM, which is a second-order polynomial of MO coefficients, into a first-order polynomial of the lifted MO coefficients and further relaxes the equality constraint for a given PMM. We also established a method to improve the accuracy of phase retrieval from the noisy PMM data by using sparsity for MO coefficients (sparse PhaseLift POT). These methods make it possible to reconstruct the three-dimensional MOs, including phases of the wave function, directly from a single experimental PMM. This method can also precisely determine the adsorption-induced molecular deformations with an accuracy of 0.05 [Å]. Furthermore, the robust sparse PhaseLift POT is robust against unavoidable noise in the experimental PMMs due to the relaxation of the matching condition for a given PMM. Therefore, this will be an innovative tool for POT, especially for analyzing the dynamics of the molecules during the chemical reaction and excitation processes.

2.
Braz J Med Biol Res ; 50(11): e6400, 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28902927

RESUMO

The aim of this study was to analyze the acute responses of bradykinin, insulin, and glycemia to exercise performed above and below lactate threshold (LT) in individuals with type 2 diabetes mellitus (T2D). Eleven participants with a diagnosis of T2D randomly underwent three experimental sessions 72 h apart: 1) 20 min of exercise performed at 120% of LT (120%LT), 2) 20 min of exercise performed at 80% of LT (80%LT), and 3) 20 min of control session. Blood glucose was analyzed before, during, and at 45 min post-exercise. Bradykinin and insulin were analyzed before and at 45 min post-exercise. Both exercise sessions elicited a parallel decrease in glucose level during exercise (P≤0.002), with a greater decrease being observed for 120%LT (P=0.005). Glucose decreased 22.7 mg/dL (95%CI=10.3 to 35, P=0.001) at the 45 min post-exercise recovery period for 80%LT and decreased 31.2 mg/dL (95%CI=18.1 to 44.4, P<0.001) for 120%LT (P=0.004). Insulin decreased at post-exercise for 80%LT (P=0.001) and control (P≤0.035). Bradykinin increased at 45 min post-exercise only for 80%LT (P=0.013), but was unrelated to the decrease in glucose (r=-0.16, P=0.642). In conclusion, exercise performed above and below LT reduced glycemia independently of insulin, but exercise above LT was more effective in individuals with T2D. However, these changes were unrelated to the increase in circulating bradykinin.


Assuntos
Glicemia/análise , Bradicinina/sangue , Diabetes Mellitus Tipo 2/sangue , Exercício Físico/fisiologia , Insulina/sangue , Ácido Láctico/sangue , Idoso , Análise de Variância , Estudos Cross-Over , Diabetes Mellitus Tipo 2/fisiopatologia , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Estatísticas não Paramétricas , Fatores de Tempo , Resultado do Tratamento
4.
J Appl Microbiol ; 117(5): 1412-21, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25040155

RESUMO

AIMS: The purpose of this study was to assess the effects of microbes on plant-available inorganic nutrients and a phytohormone in rice-derived distillery effluents. METHODS AND RESULTS: The effects of 37 microbial strains on the components of distillery effluents were investigated. Inoculation of several Aspergillus and Bacillus strains resulted in accumulation of a large quantity of ammonium nitrogen (NH4-N; 774 ± 490 and 1059 ± 463 mg l(-1), respectively) in the effluent. However, a decrease in the liquid phase during Aspergillus incubation suggested the requirement for additional treatment of the solid residue, whereas the growth of Bacillus subtilis was inhibited by the acidic conditions in the raw distillery effluent. Interestingly, Aspergillus caelatus, Aspergillus oryzae and Aspergillus tamarii yielded greater increases in nitrate concentrations (30-39 mg l(-1)). Colorimetric and gas chromatography-mass spectrometry analyses revealed that Wickerhamomyces strains generated 7-26 mg l(-1) of indole-3-acetic acid (IAA) when the effluent pH was adjusted to 7·0. CONCLUSIONS: Inoculation of several Aspergillus and Bacillus strains into distillery effluents resulted in the production of a large quantity of NH4-N. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides information that will facilitate the bioconversion of distillery effluent into fast-acting liquid fertilizers.


Assuntos
Aspergillus/metabolismo , Bacillus/metabolismo , Fertilizantes , Oryza/química , Águas Residuárias/química , Compostos de Amônio/química , Biodegradação Ambiental , Destilação , Ácidos Indolacéticos/metabolismo , Nitratos/análise , Nitrificação , Nitrogênio/análise
5.
Int J Sports Med ; 33(7): 550-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22499573

RESUMO

The aim of the present study was to investigate the effects of resistance training on glycogen content and muscle cross-sectional area (CSA) in ovariectomized rats. Wistar rats were divided into: sedentary; ovariectomized sedentary; resistance trained; and ovariectomized resistance trained. In the 12-week resistance training, the animals climbed a 1.1 m vertical ladder, 3 days per week, with 4-8 climbs. Cardiac, liver and muscle glycogen content was determined. After the 12-week resistance training period there was a higher hepatic and muscle glycogen content in the resistance training group compared with the other groups (p<0.01). CSA was higher in soleus for the resistance trained, ovariectomized resistance trained and sedentary compared with ovariectomized sedentary (p<0.05). Ovariectomy attenuated the increase in liver and muscle glycogen content, while soleus muscle cross-sectional area increased with resistance training, even in ovariectomized rats. Resistance training could be an important exercise to increase muscle function in situations of reduced estrogen and progesterone.


Assuntos
Glicogênio/metabolismo , Músculo Esquelético/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Feminino , Fígado/metabolismo , Miocárdio/metabolismo , Ovariectomia , Ratos , Ratos Wistar , Treinamento Resistido
6.
J Appl Microbiol ; 111(4): 915-24, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21790914

RESUMO

AIMS: To develop a rapid and simple genus-specific polymerase chain reaction (PCR) method for detecting and identifying isolates of the genus Azospirillum which is well-recognized as plant growth-promoting rhizobacterium. METHODS AND RESULTS: Nine pairs of PCR primers were designed based on the Azospirillum 16S rRNA, ipdC, nifA and nifH genes to assess their genus specificity by testing against 12 Azospirillum (from seven species) and 15 non-Azospirillum reference strains, as compared with the fAZO/rAZO pair reported by Baudoin et al. (J Appl Microbiol, 108, 2010, 25). Among the primer pairs assessed, the Az16S-A pair designed on the 16S rRNA gene sequence showed the highest genus specificity: it successfully yielded a single amplicon of the expected size in all the 12 Azospirillum strains and for a close relative, Rhodocista centenaria. The PCR with the Az16S-A primers generated a detectable amount of the amplicon from ≥10³ CFU ml⁻¹ of Azospirillum cell suspensions even in the presence of contaminants and accurately discriminated Azospirillum and non-Azospirillum species in both 35 Azospirillum-like and 70 unknown isolates from plant roots and rhizosphere soils. CONCLUSIONS: We developed a rapid and simple PCR method for detecting and identifying Azospirillum isolates within populations of rhizosphere bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: The method developed would serve as a useful tool for isolating a variety of indigenous Azospirillum bacteria from agricultural samples.


Assuntos
Azospirillum/classificação , Reação em Cadeia da Polimerase/métodos , Rizosfera , Microbiologia do Solo , Azospirillum/genética , Azospirillum/isolamento & purificação , Sequência de Bases , Primers do DNA/genética , DNA Bacteriano/genética , Genes Bacterianos , Limite de Detecção , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
7.
Int J Oral Maxillofac Surg ; 38(3): 296-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19167190

RESUMO

A case of large cell neuroendocrine carcinoma (LCNEC) of the tongue base is described. It was characterized by solid tumor nests with central necrosis and rosette formation resembling basaloid squamous cell carcinoma. Immunohistochemical examination revealed that this tumor had neuroendocrine differentiation. It was diagnosed as LCNEC of the tongue base. Pulmonary LCNEC is a well-established entity, but LCNEC also occurs in other organs. This is the first report of mucosal LCNEC in the oral cavity. Basal cells in the normal squamous epithelium around the tumor indicated positivity for neural cell adhesion molecule and N-cadherin. These cells were considered neuroendocrine-related cells in the lingual squamous epithelium, which are related to the tumorigenesis of mucosal LCNEC in the tongue base.


Assuntos
Carcinoma de Células Grandes/patologia , Carcinoma Neuroendócrino/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Primárias Múltiplas/patologia , Neoplasias da Língua/patologia , Idoso , Antígenos de Neoplasias/imunologia , Carcinoma de Células Grandes/imunologia , Carcinoma de Células Grandes/cirurgia , Carcinoma Neuroendócrino/imunologia , Carcinoma Neuroendócrino/cirurgia , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/cirurgia , Diagnóstico Diferencial , Humanos , Neoplasias Hipofaríngeas/patologia , Neoplasias Hipofaríngeas/cirurgia , Imuno-Histoquímica , Masculino , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias da Língua/imunologia , Neoplasias da Língua/cirurgia , Resultado do Tratamento
8.
Res Vet Sci ; 84(3): 465-70, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17662319

RESUMO

Several animal studies have demonstrated the beneficial effects of hypertonic saline (HSS) on cerebral blood flow, intracranial pressure and brain water content. This study aimed to investigate, using magnetic resonance imaging, whether a small volume of HSS is superior to dextran in vasodilatation of cerebral vessels and reduction of cerebrospinal fluids in dogs. HSS induced a significant expansion of the cross-section of the superior sagittal sinus in the axial transverse section of the pituitary and a decrease in cerebrospinal fluid area in the axial transverse section of the epencephalon more than dextran 40 did (p<0.001, respectively). However, the relative plasma volume in the dog which received dextran 40 was significantly higher after t=30min than in the HSS group (p<0.001). Therefore, it is suggested that HSS might be superior to colloid solutions in improving cerebral circulation, whereas dextran 40 is superior to HSS in enhancing systemic circulation in dogs.


Assuntos
Circulação Cerebrovascular/fisiologia , Solução Salina Hipertônica/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Circulação Cerebrovascular/efeitos dos fármacos , Cães , Pressão Intracraniana/efeitos dos fármacos , Pressão Intracraniana/fisiologia , Sistema Límbico/efeitos dos fármacos , Sistema Límbico/fisiologia , Imageamento por Ressonância Magnética , Masculino
9.
Artigo em Inglês | MEDLINE | ID: mdl-19163641

RESUMO

Multi-finger structure was proposed to improve flexibility of the CMOS LSI-based multi-chip retinal stimulator. A dual-finger retinal stimulator was fabricated and its functionality was demonstrated in retinal stimulation experiments on rabbit's retina, We also proposed an idea of pulsed-powering operation scheme for the multi-chip flexible retinal stimulator. We compared the pulsed-powering scheme with conventional one in a simulation, and show that the pulsed-powering can be an alternative operation scheme for the neural stimulator that provides an improved safety to the biological tissue.


Assuntos
Terapia por Estimulação Elétrica/instrumentação , Estimulação Elétrica/instrumentação , Potenciais Evocados Visuais/fisiologia , Retina/fisiologia , Terapia Assistida por Computador/instrumentação , Córtex Visual/fisiologia , Algoritmos , Animais , Limiar Diferencial , Estimulação Elétrica/métodos , Terapia por Estimulação Elétrica/métodos , Desenho de Equipamento , Próteses e Implantes , Coelhos , Retina/anatomia & histologia , Semicondutores , Processamento de Sinais Assistido por Computador/instrumentação , Software , Terapia Assistida por Computador/métodos
10.
Artigo em Inglês | MEDLINE | ID: mdl-18003329

RESUMO

We have performed in vivo electric stimulation experiments on rabbit retina to demonstrate feasibility of CMOS LSI-based multi-chip flexible neural stimulator for retinal prosthesis. We have developed new packaging structure with an improved flexibility and device control system which totally controls the LSI-based multi-chip stimulator, counter electrode, and stimulation generator. We have implanted the fabricated multi-chip stimulator into sclera pocket for STS (Suprachoroidal Transretinal Stimulation) configuration. We successfully obtained EEP (Electrically Evoked Potential) on visual cortex evoked by the multi-chip stimulator.


Assuntos
Terapia por Estimulação Elétrica/instrumentação , Estimulação Elétrica/instrumentação , Potenciais Evocados Visuais/fisiologia , Próteses e Implantes , Células Ganglionares da Retina/fisiologia , Terapia Assistida por Computador/instrumentação , Córtex Visual/fisiologia , Animais , Limiar Diferencial , Estimulação Elétrica/métodos , Terapia por Estimulação Elétrica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Coelhos , Valores de Referência , Semicondutores , Processamento de Sinais Assistido por Computador/instrumentação , Terapia Assistida por Computador/métodos
12.
Kyobu Geka ; 56(8 Suppl): 661-6, 2003 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-12910947

RESUMO

With the rapid advance of percutaneous catheter intervention, the direction taken by surgeons is not only to make coronary artery bypass grafting (CABG) less invasive but also to obtain better long-term results by using more arterial conduits. However, off-pump CABG (OPCAB) with only in situ arterial conduits such as the left and right internal thoracic arteries (ITAs) and the right gastroepiploic artery (RGEA) is technically demanding for the surgeon. The purpose of this study was to demonstrate the feasibility and safety of this technique. From January 2002 to December 2002, 57 patients underwent isolated CABG without cardiopulmonary bypass, excluding minimally invasive direct coronary artery bypass (MIDCAB) cases. There were 44 men and 13 women with a mean age of 64.1 years. Most of the patients (95%) underwent postoperative angiography within 1 month after surgery. The mean number of anastomoses was 3.8 +/- 1.4 (range 2-8). One patient suffered from mediastinitis and another from stroke. All patients were discharged from the hospital. Fifty patients (88%) received only in situ grafts for complete revascularization. Forty-one patients received bilateral ITAs and 27 received bilateral ITAs and RGEA. The mean number of anastomoses using bilateral ITAs and RGEA was 4.5 +/- 1.2 (range 3-8). The patency rate was 98%. Complete arterial revascularization with only in situ arterial conduits was associated with minimal operative risk and a high early graft patency rate, even in the off-pump situation. These results indicate that complete revascularization can be achieved in OPCAB with the exclusive use of in situ arterial conduits in patients with diffuse coronary arterial disease.


Assuntos
Ponte de Artéria Coronária/métodos , Doença das Coronárias/cirurgia , Adulto , Idoso , Anastomose Cirúrgica/métodos , Ponte Cardiopulmonar , Vasos Coronários/cirurgia , Feminino , Artéria Gastroepiploica/transplante , Humanos , Masculino , Artéria Torácica Interna/transplante , Pessoa de Meia-Idade , Estudos Retrospectivos , Toracotomia/métodos , Coleta de Tecidos e Órgãos/métodos , Resultado do Tratamento , Grau de Desobstrução Vascular
13.
Biol Pharm Bull ; 24(6): 643-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11411552

RESUMO

Extract of Gymnema sylvestre leaves was administered to rats receiving either a high fat diet or normal fat diet for 10 weeks to investigate its influence on plasma and liver lipids and on visceral fat accumulation. In addition, its effect was compared with those of chitosan and the influence of combined use of these two substances was also evaluated. Within the high fat diet groups, the extract suppressed body weight gain and accumulation of liver lipids to the same extent as chitosan and the combined use. In addition, intraperitoneal fat and fat drop vacuoles on the epithelium of renal tubules, noted in the high fat diet group, were scattered by administration of the extract with the same results as for chitosan and combined use. Within the normal fat diet groups, plasma triglyceride levels decreased by administration of the extract, with similar results as chitosan and combined use. Concerning plasma total cholesterol, there was no decreasing effects with the extract, as found with chitosan and combined use. However, the effect of chitosan on plasma total cholesterol tended to be enhanced when used in combination with the extract. In addition, long-term administration of the extract did not show any influence on hematological and blood chemical parameters.


Assuntos
Fígado/efeitos dos fármacos , Magnoliopsida/química , Extratos Vegetais/farmacologia , Triglicerídeos/metabolismo , Animais , Gorduras na Dieta/administração & dosagem , Comportamento Alimentar , Fígado/metabolismo , Masculino , Tamanho do Órgão , Ratos , Ratos Wistar , Triglicerídeos/sangue
14.
Biol Pharm Bull ; 24(6): 713-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11411567

RESUMO

Extract of Gymnema sylvestre R. Br leaves (GE) was orally administered once a day to rats fed a high fat diet or normal fat diet for 3 weeks to investigate its influence on lipid metabolism. As a result, GE did not influence body weight gain or feed intake in both diet groups during the experimental period. The apparent fat digestibility was significantly decreased by GE in both diet groups for the last 2 weeks of the experimental period, though not the apparent protein digestibility. In addition, the excretion of neutral sterols and acid steroids into feces was increased by GE in both diet groups. Furthermore, GE decreased the total cholesterol and triglyceride levels in serum. On the other hand, blood lecithin-cholesterol acyltransferase (LCAT) activity was increased by GE. Moreover, it was suggested that GE influenced cecal fermentation and that propionic acid and acetic acid contents in cecum were significantly increased by GE. Consequently, it was suggested that GE improved serum cholesterol and triglyceride levels through influence over a wide range of lipid metabolism in rats.


Assuntos
Colesterol/sangue , Magnoliopsida/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Triglicerídeos/sangue , Animais , Peso Corporal , Gorduras na Dieta/metabolismo , Proteínas Alimentares/metabolismo , Fezes/química , Comportamento Alimentar , Masculino , Tamanho do Órgão , Fosfatidilcolina-Esterol O-Aciltransferase/sangue , Ratos , Ratos Wistar
15.
Biol Pharm Bull ; 24(3): 307-10, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11256491

RESUMO

The methanol soluble portion of black cumin oil, which is prepared by compression of seeds of Nigella sativa L., showed inhibitory effects on arachidonic acid (AA)-induced platelet aggregation and blood coagulation. By bioactive assay of AA-induced platelet aggregation, the methanol soluble part was purified to isolate a new compound 2-(2-methoxypropyl)-5-methyl-1,4-benzenediol (1) and two known compounds, thymol (2), carvacrol (3), having very strong inhibitory activity. Further, we then examined the isolated compounds (1-3) and eight related compounds by the screening test for AA-induced platelet aggregation. Compounds possessing aromatic hydroxyl and acetoxyl group had more potent activity than aspirin, which is well known as a remedy for thrombosis.


Assuntos
Apiaceae/química , Fibrinolíticos/farmacologia , Plantas Medicinais/química , Animais , Coagulação Sanguínea/efeitos dos fármacos , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/química , Cromatografia Gasosa-Espectrometria de Massas , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Masculino , Rotação Ocular , Agregação Plaquetária/efeitos dos fármacos , Coelhos , Sementes/química
16.
Scand J Infect Dis ; 33(12): 927-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11868767

RESUMO

Human infection with Streptococcus canis is extremely rare. We describe herein a case of septicemia with cellulitis caused by S. canis in a 75-y-old woman, which developed 2 weeks after a dog bite. Macrorestriction analysis with pulsed-field gel electrophoresis demonstrated that the organism had been transmitted by means of a dog bite to her hand.


Assuntos
Bacteriemia/transmissão , Mordeduras e Picadas/microbiologia , Cães/microbiologia , Infecções Estreptocócicas/transmissão , Streptococcus/isolamento & purificação , Idoso , Animais , Bacteriemia/fisiopatologia , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Recidiva , Infecções Estreptocócicas/fisiopatologia
17.
J Heart Valve Dis ; 10(6): 750-3, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11767181

RESUMO

The Ross procedure, which includes removal of the malformed aortic valve and replacement of a pulmonary autograft in the aortic position, has increased the number of available treatment options. Recently, dilatation of the autograft pulmonary root after the Ross procedure has been reported as a complication. We report a patient with bicuspid aortic valve malformations and aortic annulus dilatation, who had a saccular-form, true-type, aneurysm in the pulmonary autograft seven months after the Ross procedure. These changes have not been described so far as complication. Pathologically, marked mucoid degeneration was noted in the tunica media of the aneurysm, as well as in the original aortic root. These findings may suggest similar pathological characteristics between the aorta and pulmonary arteries. Hence, the surgical risks accompanying vascular characteristics in patients with congenital aortic valve malformations should be considered.


Assuntos
Insuficiência da Valva Aórtica/etiologia , Valva Aórtica/anormalidades , Valva Aórtica/cirurgia , Aneurisma Intracraniano/etiologia , Valva Mitral/anormalidades , Valva Mitral/cirurgia , Complicações Pós-Operatórias , Valva Pulmonar/transplante , Adulto , Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/diagnóstico , Insuficiência da Valva Aórtica/cirurgia , Aortografia , Dilatação Patológica/diagnóstico , Dilatação Patológica/etiologia , Dilatação Patológica/cirurgia , Humanos , Aneurisma Intracraniano/diagnóstico , Aneurisma Intracraniano/cirurgia , Masculino , Valva Mitral/diagnóstico por imagem , Valva Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Transplante Autólogo
18.
Cancer Immunol Immunother ; 50(10): 539-48, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11776376

RESUMO

For the purpose of establishing a new adoptive immunotherapy for bile duct carcinoma (BDC), we have directed our attention to superantigens (SAgs), the most potent known activators of T lymphocytes. In our previous study, staphylococcal enterotoxin A (SEA) was conjugated chemically with MUSE11 mAb, which recognizes the MUC1 cancer-associated antigen, and shown to enhance the specific cytotoxic activity of T-LAK cells against MUC1-expressing BDC cells (TFK-1) in vitro and in vivo. However, it is probable that SEA might cause side-effects because of nonspecific binding to class II positive cells. In order to overcome these, we generated mutated SEA (mSEA) by changing Asp at position 227 of native SEA to Ala, which has reduced affinity to MHC class II molecules, but retains the potential for T cell activation. When mSEA-D227A was administered to rabbits to examine effects on blood pressure, 500 times more mSEA-D227A was tolerated than native SEA. This prompted us to construct a mSEA-D227A-conjugated mAb, reactive with MUC1. It augmented the antitumor activity of T-LAK cells significantly, and furthermore, mSEA-D227A could be conjugated to two bispecific antibodies, BsAb (anti-MUC1 x anti-CD3) and BsAb (anti-MUC1 x anti-CD28), which in combination had greater enhancing effects than mSEA-D227A-conjugated anti-MUC1 mAb, and combination of unconjugated BsAbs. These findings indicate a utility of mSEA-D227A-conjugated antibodies for targeted cancer immunotherapy.


Assuntos
Anticorpos Monoclonais/imunologia , Neoplasias dos Ductos Biliares/imunologia , Enterotoxinas/imunologia , Imunoterapia Adotiva , Mucina-1/imunologia , Substituição de Aminoácidos , Animais , Anticorpos Monoclonais/uso terapêutico , Neoplasias dos Ductos Biliares/terapia , Citotoxicidade Imunológica , Enterotoxinas/genética , Feminino , Humanos , Camundongos , Camundongos SCID , Transplante de Neoplasias , Superantígenos/imunologia
19.
Protein Eng ; 13(8): 583-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10964988

RESUMO

Diabodies are the recombinant bispecific antibodies (BsAbs), constructed from heterogeneous single-chain antibodies. Usually, diabodies have been prepared from bacterial periplasmic fraction using a co-expression vector (i.e. genes encoding two chains were tandemly located under the same promoter). Some diabodies, however, cannot be expressed as a soluble material owing to inclusion body formation, which limits the utilization of diabodies in various fields. Here we report an improved method for the construction of diabodies using a refolding system. As a model, a bispecific diabody binding to adenocarcinoma-associated antigen MUC1 and to CD3 on T cells was studied. One chain consisted of a VH specific for MUC1 linked to a VL specific for CD3 with a short polypeptide linker (GGGGS). The second was composed of a VL specific for MUC1 linked to a VH specific for CD3. The two hetero scFvs were independently obtained from intracellular insoluble fractions of Escherichia coli, purified, mixed stoichiometrically (at an equivalent molar ratio of 1:1) and refolded. The refolded two hetero scFv has a hetero-dimeric structure, with complete specificity for both target cells [i.e. MUC1 positive cells and CD3 positive lymphokine-activated killer cells with a T cell phenotype (T-LAK)]. Evaluation of the in vitro efficacy of T-LAK with the diabody by growth inhibition assay of cancer cells demonstrated maximum growth inhibition of cancer cells to reach approximately 98% at an effector:target ratio (E:T ratio) of 10, almost identical with that with anti-MUC1xanti-CD3 chemically synthesized BsAbs (c-BsAbs). This is the first report of the construction of a diabody using a refolding system.


Assuntos
Anticorpos Biespecíficos/química , Anticorpos Biespecíficos/genética , Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/isolamento & purificação , Divisão Celular/imunologia , Escherichia coli/genética , Citometria de Fluxo , Peso Molecular , Dobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação
20.
FEBS Lett ; 476(3): 266-71, 2000 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-10913626

RESUMO

The most predominant co-stimulation pathway, which is critical for T cell activation and proliferation, is the CD28-B7 pathway. The anti-CD28 monoclonal antibody (mAb) also provides a co-stimulatory signal to T cells. In order to construct a functional Fv fragment (complex of VH and VL domains) of anti-CD28 antibody using a bacterial expression system, cDNA encoding the variable regions of immunoglobulin from 15E8 hybridoma cells was cloned and expressed in Escherichia coli. The Fv fragment was obtained as a soluble protein from the periplasmic fraction and showed a binding pattern similar to parental IgG. The Fv fragment induced proliferation of peripheral blood mononuclear cells in the presence of anti-CD3 or anti-CD2 mAb and enhanced anti-tumor activity of anti-MUC1x(anti)-CD3 bispecific antibody when tested with lymphokine-activated killer cells with T cell phenotype. Thus, the anti-CD28 Fv fragment will be promising not only for the study of co-stimulation, but also for cancer immunotherapy.


Assuntos
Antígenos CD28/imunologia , Fragmentos de Imunoglobulinas/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Sequência de Bases , Divisão Celular , Clonagem Molecular , Citotoxicidade Imunológica , DNA Recombinante/genética , Escherichia coli/genética , Humanos , Hibridomas , Fragmentos de Imunoglobulinas/genética , Imunoterapia , Células Matadoras Ativadas por Linfocina/imunologia , Ativação Linfocitária , Camundongos , Dados de Sequência Molecular , Linfócitos T/citologia , Células Tumorais Cultivadas
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