Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 14(1): 4188, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378702

RESUMO

Female athletes who endure intense training are at risk of developing the 'female athlete triad,' making energy intake management crucial. However, the fluctuations in estradiol and progesterone levels throughout the menstrual cycle present a challenge in maintaining consistent energy intake. This study aimed to uncover the underlying factors associated with appetite regulation linked to menstrual phases and exercise using proteomic approach. Five female athletes engaged in 60 min of bicycle exercise, followed by 90 min of rest, during both the follicular and luteal phases. Serum samples were collected before, during, and after exercise, and the serum proteome was analyzed using 2D-gel electrophoresis. A total of 511 spots were detected in the subjects' serum profiles, with significant decreases observed in haptoglobin during the luteal phase and complement component 3 during bicycle training. Unsupervised learning with a generalized estimating equation analysis showed that serum peptide YY (PYY), an appetite suppressor, significantly influenced the fluctuations of serum proteins induced by exercise (p < 0.05). Regression analysis demonstrated a positive correlation between PYY and serum IgM (R = 0.87), implying that the intestinal environment and the immune response in female athletes may contribute to appetite regulation.


Assuntos
Apetite , Proteômica , Humanos , Feminino , Apetite/fisiologia , Projetos Piloto , Progesterona , Ciclo Menstrual/fisiologia , Atletas , Peptídeo YY
2.
Int J Surg Case Rep ; 109: 108556, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37542884

RESUMO

INTRODUCTION: Cardiopulmonary resuscitation (CPR) can sometimes induce organ injury, however, such an occurrence is rare. We herein report a case of liver injury due to CPR with life-threatening pulmonary embolization (PE) that required the patient to undergo surgical hemostasis and antithrombotic therapy. PRESENTATION OF CASE: A woman in her 70s fell off her bicycle. She suffered cardiopulmonary arrest and underwent CPR. She was diagnosed with PE and underwent catheter treatment and anticoagulant therapy; however, her blood pressure did not increase. Contrast-enhanced computed tomography revealed injury to the liver and inferior phrenic artery. Hemostasis could not be completely achieved by transcatheter arterial embolization alone. She was therefore transferred to our hospital and underwent damage control surgery (DCS). Definitive surgery (DS) performed 33 h after DCS showed right hepatic subcapsular hematoma and left hepatic subcapsular hematoma. We cut away the capsules and removed the hematomas. There were lacerations and oozing under the capsule in the left lobe. We sutured the laceration. At 72 h after undergoing DS, antithrombotic therapy was started. On day 19, the patient was discharged home by herself without any neurological damage. DISCUSSION: For a case of liver injury due to CPR with life-threatening PE, treatment with both hemostasis and antithrombotic therapy should be performed. Antithrombotic therapy was started appropriately in this case by accurately identifying the liver laceration and suturing it. CONCLUSION: Hemostasis following both DCS and DS with appropriate anticoagulant therapy was effective for the management of liver injury due to CPR with life-threatening PE.

3.
Sci Rep ; 12(1): 14002, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35977993

RESUMO

Even though hematopoietic stem cell transplantation (HSCT) allows successful treatment for many malignant and non-malignant disorders, its curative potential remains limited by severe side effects, including infections and other transplant-related complications such as graft-versus-host disease (GvHD). This study examined changes in serum proteome via high-performance two-dimensional gel electrophoresis (2-DE) during HSCT to search for diagnostic biomarkers for post-HSCT complications. Longitudinal proteomic analysis revealed proteins related to metabolic complications and hemolytic anemia. Retinol-binding protein 4 (RBP4), a reliable marker of insulin resistance, was identified, and is possibly associated with the onset mechanism of acute graft-versus-host disease (aGvHD) and/or skin GvHD. Although the cause of insulin resistance is not fully understood, it is thought to be associated with adipocytes inflammation induced by RBP4, iron overload and hemolytic anemia after HSCT, as observed in this study. The present study has demonstrated that insulin resistance and metabolic complications could be immediate complications after transplantation and are associated with aGvHD. The biomarkers revealed in this study are promising tools to be used for improving the early diagnosis of HSCT-associated complications, especially aGvHD, possibly even before clinical manifestations.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Resistência à Insulina , Biomarcadores , Doença Enxerto-Hospedeiro/patologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Proteômica , Proteínas Plasmáticas de Ligação ao Retinol , Transplante Homólogo/efeitos adversos
4.
BMC Res Notes ; 12(1): 785, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783915

RESUMO

OBJECTIVE: NRK is a unique X chromosome-linked protein kinase expressed predominantly in placenta. The gene knockout causes placental overgrowth and delayed labor of Nrk-null fetuses from dams in mouse. To clarify unknown mechanisms behind the Nrk-null phenotypes, protein expression profiles were analyzed in the Nrk-null placenta using a high-performance two-dimensional electrophoresis methodology. RESULTS: Among around 1800 spots detected, we characterized a dozen protein spots whose expression levels were significantly altered in the Nrk-null placenta compared to wild-type. Analyzing these data sets is expected to reflect the difference physiologically in the presence or absence of NRK, facilitating the development of therapeutic strategies.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Placenta/enzimologia , Placenta/fisiologia , Proteínas Serina-Treonina Quinases/genética , Proteômica , Animais , Eletroforese em Gel Bidimensional , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Gravidez , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/metabolismo
5.
BMC Mol Cell Biol ; 20(1): 38, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455216

RESUMO

BACKGROUND: Flotillin-2 (Flot2) is a lipid raft scaffold protein that is thought to be related to neural differentiation. Flot2 is phosphorylated by Fyn, a Src kinase, and causes raft-dependent endocytosis; however, the exact role of Flot2 in neural differentiation remains unclear. To reveal the roles of lipid raft-associated proteins during neural differentiation, we tried to analyze the expression and localization. RESULTS: In this study, we found that the expression levels of the Flot2 and Fyn proteins increased in whole-cell lysates of P19C6 cells after neural differentiation. In addition, sucrose density fractionation and immunofluorescence experiments revealed an increase in the localization of Flot2 and Fyn to lipid rafts after neural differentiation. We also found that Fyn partially colocalized with Flot2 lipid rafts in neural cells. CONCLUSION: The observed distribution of Fyn and level of inactivated Fyn and/or c-Src in detergent-resistant membrane (DRM) fractions suggests that the amount of activated Fyn might increase in DRM fractions after neural differentiation. Overall these findings suggest that Flot2 lipid rafts are associated with Fyn, and that Fyn phosphorylates Flot2 during neural differentiation of P19C6 cells.


Assuntos
Diferenciação Celular , Microdomínios da Membrana/metabolismo , Proteínas de Membrana/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Animais , Linhagem Celular Tumoral , Camundongos , Proteínas Proto-Oncogênicas c-fyn/metabolismo
6.
JA Clin Rep ; 5(1): 48, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32025934

RESUMO

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) can control massive postpartum hemorrhage. CASE PRESENTATION: A 41-year-old woman transferred to hospital following cesarean section presented in refractory hemorrhagic shock. REBOA was blindly performed in the emergency department. She immediately underwent hysterectomy and damage control surgery in the operating room. The aortic balloon, whose position was confirmed at zone II by postoperative X-ray, provided intermittent occlusion for 40 min during surgery. Hemodynamics were stabilized with these interventions, with massive transfusion required for severe coagulopathy perioperatively. She gradually recovered with intensive care but suffered ascending colon ischemia with perforation on day 16. She received a colostomy and was discharged without sequelae after 130 days. Amniotic fluid embolism was diagnosed according to clinical criteria and supplemental serum markers. CONCLUSIONS: This patient suffered colonic ischemia possibly due to REBOA used to manage amniotic fluid embolism. REBOA requires careful consideration to avoid complications.

8.
PLoS One ; 13(6): e0199117, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29912936

RESUMO

The effects of the high-dose ionizing radiation used in radiotherapy have been thoroughly demonstrated in vitro and in vivo. However, the effects of low-dose ionizing radiation (LDIR) such as computed tomography-guided biopsies and X-ray fluoroscopy on skin cells remain controversial. This study investigated the molecular effects of LDIR on the human primary keratinocytes (HPKs) and U937 cells, monocytes-like cell lines. These cells were exposed to 0.1 Gray (Gy) X-ray as LDIR. The modulation of transcription was assessed using a cDNA array, and the protein expression after LDIR exposure was investigated using isobaric tags for relative and absolute quantification (iTRAQ) proteomic analysis at 24 hours. These effects were confirmed by immunoblotting analysis. The direct effects of LDIR on the U937 cells and HPKs and the bystander effects of irradiated HPKs on U937 cells were also investigated. LDIR downregulated c-Myc in both U937 cells and HPKs, and upregulated the p21WAF1/CIP1 protein expression in U937 cells along with the activation of TGFß and protein phosphatase 2A (PP2A). In HPKs, LDIR downregulated the mTOR signaling with repression of S6 and 4EBP1 activation. Similar changes were observed as bystander effects of LDIR. Our findings suggest that LDIR inhibits protein synthesis and induces the cytokines activation associated with inflammation via direct and bystander effects, which might recapitulate the effects of LDIR in inflammated skin structures.


Assuntos
Ciclo Celular/efeitos da radiação , Queratinócitos/efeitos da radiação , Biossíntese de Proteínas/efeitos da radiação , Células U937/efeitos da radiação , Raios X/efeitos adversos , Expressão Gênica/efeitos da radiação , Humanos , Immunoblotting , Queratinócitos/metabolismo , Espectrometria de Massas , Redes e Vias Metabólicas/efeitos da radiação , Análise de Sequência com Séries de Oligonucleotídeos , Proteômica , Células U937/metabolismo
9.
Chem Commun (Camb) ; 50(22): 2962-4, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24317094

RESUMO

A peptide that binds and emits fluorescence in response to conformational change in a target protein was developed by in vitro selection using tRNA carrying a fluorogenic amino acid. This technology could prove to be useful for the development of separation-free immunoassays and bio-imaging analyses.


Assuntos
Aminoácidos/metabolismo , Calmodulina/metabolismo , Corantes Fluorescentes/metabolismo , Peptídeos/metabolismo , Aminoácidos/química , Azóis/química , Corantes Fluorescentes/química , Nitrobenzenos/química , Peptídeos/química , Ligação Proteica , RNA de Transferência
10.
Acute Med Surg ; 1(2): 122-125, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29930835

RESUMO

CASE: The patient's chart was reviewed, summarized, and presented. OUTCOME: A 41-year-old male collapsed after complaining of dyspnea just before the end of a hemodialysis session. He was just being introduced to hemodialysis. The patient's percutaneous oxygen saturation dropped to 50% even under inhalation of 10 L/minute of oxygen and he developed pulseless electrical activity. After tracheal intubation, a return of spontaneous circulation was noted. His truncal CT disclosed a bilateral diffuse ground glass appearance and pleural effusion were noted. Induced mild hypothermic therapy and mechanical ventilation resulted in the improvement of his respiratory function and consciousness. A coronary angiogram and left ventriculography showed no significant lesion, and his pulmonary edema was considered to have been induced by over-hydration due to renal failure, diastolic heart failure or dialysis disequilibrium syndrome. He was discharged without any neurological deficit. CONCLUSION: Tracheal intubation with ventilation for hypoxic cardiopulmonary arrest and induced hypothermic therapy after obtaining spontaneous circulation may be factors of favorable outcome of this case.

11.
Med Mol Morphol ; 46(1): 14-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23325550

RESUMO

Lymphocyte enhancer factor 1 (LEF1), a member of the LEF/T-cell-specific factor (TCF) family of the high mobility group domain transcription factors, acts downstream in canonical Wnt signaling. Aberrant transactivation of LEF1 contributes to the tumorigenesis of colonic neoplasms, sebaceous skin tumors, and lymphoblastic leukemia. LEF1-associated proteins are crucial for regulating its transcriptional activity. In this study, glutathione-S-transferase pull-down assay and mass spectrometry enabled identification of the DNA-dependent protein kinase catalytic subunit (DNA-PKcs) as a novel interaction partner for LEF1. The interaction between LEF1 and DNA-PKcs was confirmed using in vivo co-immunoprecipitation. Furthermore, double immunofluorescence observations showed that LEF1 and DNA-PKcs colocalized in the nuclei of colon adenocarcinoma cell lines. Identification of the interaction between LEF1 and DNA-PKcs may provide clues for a novel therapy for cancer treatment as well as for understanding LEF1-mediated transcriptional regulation.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias do Colo/metabolismo , Proteína Quinase Ativada por DNA/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Via de Sinalização Wnt/genética , Domínio Catalítico/genética , Linhagem Celular Tumoral , Proteína Quinase Ativada por DNA/genética , Imunofluorescência , Glutationa Transferase , Humanos , Imunoprecipitação , Espectrometria de Massas
12.
Biochem Biophys Res Commun ; 407(2): 343-7, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21392500

RESUMO

Tyrosine hydroxylase (TH) is the rate-limiting enzyme in catecholamine biosynthesis, and its N-terminus plays a critical role in the intracellular stability of the enzyme. In the present study, we investigated the mechanism by which the N-terminal region of TH affects this stability. TH molecules phosphorylated at their Ser31 and Ser40 were localized predominantly in the cytoplasm of PC12D cells. However, those molecules phosphorylated at Ser19 were found mainly in the nucleus, whereas they seemed to be negligible in the cytoplasm. The inhibition of proteasomes increased the quantity of TH molecules phosphorylated at their Ser19 and Ser40, although it did not increase that of TH molecules or that of TH phosphorylated at its Ser31. The inhibition of autophagy did not affect the amount of the TH molecule or that of its three phosphorylated forms. Deletion mutants of human TH type-1 lacking the N-terminal region containing the three phosphorylation sites possessed high stability of the enzyme in PC12D cells. These results suggest that the phosphorylation of the N-terminal portion of TH regulates the degradation of this enzyme by the ubiquitin-proteasome pathway.


Assuntos
Complexo de Endopeptidases do Proteassoma/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Ubiquitina/metabolismo , Animais , Autofagia , Humanos , Lisossomos/enzimologia , Células PC12 , Fosforilação , Estrutura Terciária de Proteína/genética , Ratos , Deleção de Sequência , Tirosina 3-Mono-Oxigenase/genética
13.
Am J Phys Med Rehabil ; 89(2): 107-14, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19661770

RESUMO

OBJECTIVE: To investigate the relation between protein expression changes in the cerebellum and improvement of motor coordination in rats with cerebral infarction. DESIGN: The rat group with treadmill training (n = 10) were compared with the rat group without treadmill training (n = 10) after 2.5 hrs of transient middle cerebral artery occlusion. Motor performance measured by the rotarod test and alteration of protein expression using two-dimensional electrophoresis based on proteomics in the cerebellum were examined. RESULTS: In behavioral evaluation, the mean latency until falling from the rotating rod in the group with treadmill training was significantly longer (P < 0.01) than that in the group without treadmill training 24 days after surgery. As for protein expression, it was revealed by proteome analysis and Western blotting that the expression of the two protein spots, 25-kDa synaptosomal-associated protein and glial fibrillary acidic protein, were significantly enhanced in the cerebellum of rats with treadmill training than that in rats without a treadmill training. CONCLUSIONS: The 25-kDa synaptosomal-associated protein and glial fibrillary acidic protein may be related to the underlying mechanisms of improvement of motor coordination and exercise-induced angiogenesis, that is, remodeling of synaptic connections and proliferation of astroglial cells, respectively.


Assuntos
Cerebelo/metabolismo , Infarto Cerebral/metabolismo , Infarto Cerebral/reabilitação , Proteína Glial Fibrilar Ácida/metabolismo , Proteína 25 Associada a Sinaptossoma/metabolismo , Animais , Eletroforese em Gel Bidimensional , Teste de Esforço , Masculino , Destreza Motora/fisiologia , Mapeamento de Peptídeos , Ratos , Ratos Sprague-Dawley , Corrida
14.
Fish Shellfish Immunol ; 28(1): 72-6, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19815107

RESUMO

The cytoplasmic tail of mammalian CD8alpha binds the kinase LCK in a zinc-dependent manner. In analogy with a previous study for humans (Kim et al., 2003) peptides were synthesized from rainbow trout CD8alpha and LCK. Surface plasmon resonance (SPR) analysis indicated that also in fish these molecules bind to each other in a zinc-dependent manner.


Assuntos
Antígenos CD8/metabolismo , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Oncorhynchus mykiss/metabolismo , Zinco/fisiologia , Animais , Sítios de Ligação , Galinhas , Humanos , Camundongos , Oncorhynchus mykiss/imunologia , Alinhamento de Sequência , Ressonância de Plasmônio de Superfície , Zinco/metabolismo
15.
J Immunol Methods ; 351(1-2): 1-12, 2009 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-19766650

RESUMO

In order to isolate monoclonal antibodies (mAbs) that bind to tumor-associated antigens (Ags) we developed the following strategy. Using the phage-display Ab library we isolated a large number of mAbs that bind to the surface of human tumor cells. The mAbs were individually screened by immunostaining, and clones that preferentially and strongly stained the malignant cells were chosen. Thereafter, the Ags recognized by the mAbs were identified. For identification of the Ags by MS candidate molecules had to be purified either by immunoprecipitation or by affinity chromatography. We isolated several hundred mAbs that showed cancer-specific staining patterns. In order to identify the Ags that were recognized by the numerous mAbs within a short time we developed two methods. Using the GFC [grouping of clones by flow cytometry (FCM)] method many Abs could be grouped by comparing the staining patterns of FCM. Members in each group turned out to bind to the same molecule in many cases. After a candidate Ag was revealed, the polypeptide corresponding to its extracellular portion was prepared and used for identification of clones that bound to the Ag among all the mAbs by SITE (simultaneous identification of clones through three dimensional ELISA) method. Both methods can be generally applicable to various kinds of membrane proteins and the mAbs against them.


Assuntos
Anticorpos Monoclonais/metabolismo , Antígenos de Neoplasias/isolamento & purificação , Técnicas de Química Combinatória , Proteínas de Membrana/isolamento & purificação , Neoplasias/metabolismo , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/química , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Antígenos de Superfície/imunologia , Bioquímica/métodos , Biblioteca Gênica , Humanos , Espectrometria de Massas , Proteínas de Membrana/biossíntese , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Ligação Proteica , RNA Interferente Pequeno/genética
16.
Immunogenetics ; 60(7): 383-97, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18560827

RESUMO

Interleukins 4 and 13 (IL-4 and IL-13) are related cytokines important for Th2 immune responses and encoded by adjacent genes on human chromosome 5. Efforts were made previously to detect these genes in fish, but research was hampered by a lack of sequence conservation. A Tetraodon nigrovirides (green spotted pufferfish) gene was annotated as IL-4 by Li et al. (Mol Immunol, 44:2078-2086, 2007), but this annotation was not well substantiated. However, the present study concludes that the reported pufferfish gene belongs to the IL-4/13 lineage indeed, while also describing an additional IL-4/13 copy in a paralogous genomic region. Our analyses of IL-4/13 loci in fish describe (1) genomic region history, (2) characteristic intron-exon organization, (3) deduced IL-4/13 molecules for several teleost fish species, (4) IL-4/13 lineage-specific protein motifs including a cysteine pair (pair 1), and (5) computer software predictions of a type I cytokine fold. Teleost IL-4/13 molecules have an additional cysteine pair (pair 2) or remnants thereof, which is absent in mammalian IL-4 and IL-13. We were unable to determine if the teleost IL-4/13 genes are orthologous to either IL-4 or IL-13, or if these mammalian genes separated later in evolution.


Assuntos
Evolução Molecular , Interleucina-13/genética , Interleucina-4/genética , Oryzias/genética , Tetraodontiformes/genética , Peixe-Zebra/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Interleucina-13/imunologia , Modelos Moleculares , Dados de Sequência Molecular , Oryzias/imunologia , Filogenia , Tetraodontiformes/imunologia , Peixe-Zebra/imunologia
17.
Biochemistry ; 47(27): 7158-66, 2008 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-18553937

RESUMO

The solution structures of complexes between calcium-saturated calmodulin (Ca (2+)/CaM) and a CaM-binding domain of the HIV-1 matrix protein p17 have been determined by small-angle X-ray scattering with use of synchrotron radiation as an intense and stable X-ray source. We used three synthetic peptides of residues 11-28, 26-47, and 11-47 of p17 to demonstrate the diversity of CaM-binding conformation. Ca (2+)/CaM complexed with residues 11-28 of p17 adopts a dumbbell-like structure at a molar ratio of 1:2, suggesting that the two peptides bind each lobe of CaM, respectively. Ca (2+)/CaM complexed with residues 26-47 of p17 at a molar ratio of 1:1 adopts a globular structure similar to the NMR structure of Ca (2+)/CaM bound to M13, which adopted a compact globular structure. In contrast to these complexes, Ca (2+)/CaM binds directly with both CaM-binding sites of residues 11-47 of p17 at a molar ratio of 1:1, which induces a novel structure different from known structures previously reported between Ca (2+)/CaM and peptide. A tertiary structural model of the novel structure was constructed using the biopolymer module of Insight II 2000 on the basis of the scattering data. The two domains of CaM remain essentially unchanged upon complexation. The hinge motions, however, occur in a highly flexible linker of CaM, in which the electrostatic residues 74Arg, 78Asp, and 82Glu interact with N-terminal electrostatic residues of the peptide (residues 12Glu, 15Arg, and 18Lys). The acidic residues in the N-terminal domain of CaM interact with basic residues in a central part of the peptide, thereby enabling the central part to change the conformations, while an acidic residue in the C-terminal domain interacts with two basic residues in the two helical sites of the peptide. The overall structure of the complex adopts an extended structure with the radius of gyration of 20.5 A and the interdomain distance of 34.2 A. Thus, the complex is principally stabilized by electrostatic interactions. The hydrophobic patches of Ca (2+)/CaM are not responsible for the binding with the hydrophobic residues in the peptide, suggesting that CaM plays a role to sequester the myristic acid moiety of p17.


Assuntos
Calmodulina/química , Antígenos HIV/química , Peptídeos/química , Espalhamento a Baixo Ângulo , Proteínas da Matriz Viral/química , Difração de Raios X , Produtos do Gene gag do Vírus da Imunodeficiência Humana/química , Animais , Modelos Moleculares , Estrutura Terciária de Proteína , Ratos , Soluções
18.
Proc Natl Acad Sci U S A ; 105(20): 7287-92, 2008 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18474866

RESUMO

Although several murine mAbs that have been humanized became useful therapeutic agents against a few malignancies, therapeutic Abs are not yet available for the majority of the human cancers because of our lack of knowledge of which antigens (Ags) can become useful targets. In the present study we established a procedure for comprehensive identification of such Ags through the extensive isolation of human mAbs that may become therapeutic. Using the phage-display Ab library we isolated a large number of human mAbs that bind to the surface of tumor cells. They were individually screened by immunostaining, and clones that preferentially and strongly stained the malignant cells were chosen. The Ags recognized by those clones were isolated by immunoprecipitation and identified by MS. We isolated 2,114 mAbs with unique sequences and identified 21 distinct Ags highly expressed on several carcinomas. Of those 2,114 mAbs 356 bound specifically to one of the 21 Ags. After preparing complete IgG(1) Abs the in vitro assay for Ab-dependent cell-mediated cytotoxicity (ADCC) and the in vivo assay in cancer-bearing athymic mice were performed to examine antitumor activity. The mAbs converted to IgG(1) revealed effective ADCC as well as antitumor activity in vivo. Because half of the 21 Ags showed distinct tumor-specific expression pattern and the mAbs isolated showed various characteristics with strong affinity to the Ag, it is likely that some of the Ags detected will become useful targets for the corresponding carcinoma therapy and that several mAbs will become therapeutic agents.


Assuntos
Anticorpos Monoclonais/química , Carcinoma/imunologia , Neoplasias/imunologia , Animais , Antígenos de Neoplasias/química , Antineoplásicos/farmacologia , Carcinoma/diagnóstico , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Humanos , Imunoglobulina G/metabolismo , Imunoterapia/instrumentação , Imunoterapia/métodos , Camundongos , Camundongos Nus , Modelos Biológicos , Neoplasias/diagnóstico , Biblioteca de Peptídeos
19.
Biochem Biophys Res Commun ; 363(3): 817-21, 2007 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-17900529

RESUMO

Tyrosine hydroxylase is the rate-limiting enzyme in catecholamine biosynthesis, and its N-terminus plays a critical role in the intracellular stability of the enzyme. In the present study, we investigated the mechanism by which the N-terminus of human tyrosine hydroxylase type 1 (hTH1) affects the stability. The results obtained by using N-terminus-deleted hTH1 mutants identified the sequence up to Ala(23) as mediating the stability. The down-regulation of 14-3-3eta proteins in PC12D cells exogenously expressing hTH1, enhanced the stability of the wild-type enzyme and that of the mutant lacking the N-terminus up to Ala(23). However, the stability of the mutant was reduced compared to the wild-type enzyme. The stability of the mutant with the N-terminus deleted up to Glu(43) was not affected by the down-regulation of 14-3-3eta. These results suggest that the 14-3-3eta protein regulates hTH1 stability by acting on the N-terminus.


Assuntos
Proteínas 14-3-3/metabolismo , Interferência de RNA , Tirosina 3-Mono-Oxigenase/metabolismo , Proteínas 14-3-3/genética , Alanina/genética , Alanina/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação/genética , Linhagem Celular Tumoral , Humanos , Líquido Intracelular/metabolismo , Dados de Sequência Molecular , Mutação , Ratos , Deleção de Sequência , Homologia de Sequência de Aminoácidos , Transfecção , Tirosina 3-Mono-Oxigenase/genética
20.
J Biol Chem ; 280(26): 24339-46, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15860459

RESUMO

Vertebrate oocytes are arrested in G(2) phase of the cell cycle at the prophase border of meiosis I. Progesterone treatment of Xenopus oocytes releases the G(2) block and promotes entry into the M phases of meiosis I and II. Substantial evidence indicates that the release of the G(2) arrest requires a decrease in cAMP and reduced activity of the cAMP-dependent protein kinase (PKAc). It has been reported and we confirm here that microinjection of either wild type or kinase-dead K72R PKAc inhibits progesterone-dependent release of the G(2) arrest with equal potency and that inhibition can be reversed by a second injection of the heat-stable inhibitor of PKAc, PKI. However, a mutant enzyme predicted to be completely kinase-dead from the crystal structure of PKAc, K72H PKAc, was much less inhibitory when carrying additional mutations that block interaction with either type I or type II regulatory subunit. Moreover, inhibition by K72H PKAc was reversed by PKI at a 30-fold lower concentration and with more rapid kinetics compared with wild type PKAc. K72R PKAc was found to have low but detectable activity after incubation in an oocyte extract. These results indicate that inhibition of the progesterone-dependent G(2)/M transition in oocytes after microinjection of dead PKAc reflects either low residual activity or binding to regulatory subunits with a resulting net increase in the level of endogenous wild type PKAc. Consistent with this hypothesis, the induction of mitosis in Xenopus egg extracts by the addition of cyclin B was blocked by wild type PKAc but not by K72H PKAc. The identification of substrates for PKAc that maintain cell cycle arrest in G(2) remains an important goal for future work.


Assuntos
Regulação Enzimológica da Expressão Gênica , Oócitos/metabolismo , Animais , Divisão Celular , Cristalografia por Raios X , AMP Cíclico/metabolismo , Ciclina B/química , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Fase G2 , Cinética , Meiose , Camundongos , Mitose , Oócitos/química , Progesterona/metabolismo , Ligação Proteica , Proteínas Recombinantes/química , Fatores de Tempo , Xenopus laevis
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA