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1.
Rev Sci Instrum ; 87(11): 11E327, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910341

RESUMO

The electron temperature at stagnation of an ICF implosion can be measured from the emission spectrum of high-energy x-rays that pass through the cold material surrounding the hot stagnating core. Here we describe a platform developed on the National Ignition Facility where trace levels of a mid-Z dopant (krypton) are added to the fuel gas of a symcap (symmetry surrogate) implosion to allow for the use of x-ray spectroscopy of the krypton line emission.

2.
Phys Rev Lett ; 114(1): 015003, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25615475

RESUMO

High-intensity x-ray pulses from an x-ray free-electron laser are used to heat and probe a solid-density aluminum sample. The photon-energy-dependent transmission of the heating beam is studied through the use of a photodiode. Saturable absorption is observed, with the resulting transmission differing significantly from the cold case, in good agreement with atomic-kinetics simulations.

3.
B-ENT ; 10(4): 299-302, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25654954

RESUMO

OBJECTIVES: To describe an extremely rare pediatric sinonasal schwannoma, and to reviewmanagement strategies and relevant literature. METHODS: Case report of pediatric sinonasal schwannoma, that was imaged with computed tomography and magnetic resonance imaging and managed endoscopically. Immunohistochemical analysis was performed to determine pathology. RESULTS: A 12-year-old girl presented with a 2-month history of progressive left exophthalmos. Imaging studies showed a large heterogeneous tumour arising from the ethmoid sinus and extending to the base of the skull and to the orbital cavity. The lesion was removed with an endonasal radical excision. The final pathological diagnosis was schwannoma. There was no tumour recurrence or any major complication during the 2-year follow up. CONCLUSION: Schwannoma should be considered in the differential diagnosis for pediatric patients with intranasal masses. Depending on the location and extent of the tumour, endonasal endoscopic excision could be a suitable management strategy.


Assuntos
Endoscopia/métodos , Seio Etmoidal/cirurgia , Neurilemoma/cirurgia , Órbita/cirurgia , Neoplasias dos Seios Paranasais/cirurgia , Base do Crânio/cirurgia , Criança , Seio Etmoidal/diagnóstico por imagem , Seio Etmoidal/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Neurilemoma/diagnóstico por imagem , Neurilemoma/patologia , Órbita/diagnóstico por imagem , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Neoplasias dos Seios Paranasais/patologia , Base do Crânio/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
Br J Cancer ; 106(11): 1833-41, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22617157

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a leading cause of death in the United States. Increased level of interleukin-8 (IL-8) and CXCR2 on tumours and in the tumour microenvironment has been associated with CRC growth, progression and recurrence in patients. Here, we aimed to evaluate the effects of tissue microenvironment-encoded IL-8 and CXCR2 on colon cancer progression and metastasis. METHODS: A novel immunodeficient, skin-specific IL-8-expressing transgenic model was generated to evaluate colon cancer growth and metastasis. Syngeneic mouse colon cancer cells were grafted in CXCR2 knockout (KO) mice to study the contribution of CXCR2 in the microenvironment to cancer growth. RESULTS: Elevated levels of IL-8 in the serum and tumour microenvironment profoundly enhanced the growth of human and mouse colon cancer cells with increased peri-tumoural angiogenesis, and also promoted the extravasation of the cancer cells into the lung and liver. The tumour growth was inhibited in CXCR2 KO mice with significantly reduced tumour angiogenesis and increased tumour necrosis. CONCLUSION: Increased expression of IL-8 in the tumour microenvironment enhanced colon cancer growth and metastasis. Moreover, the absence of its receptor CXCR2 in the tumour microenvironment prevented colon cancer cell growth. Together, our study demonstrates the critical roles of the tumour microenvironment-encoded IL-8/CXCR2 in colon cancer pathogenesis, validating the pathway as an important therapeutic target.


Assuntos
Neoplasias do Colo/metabolismo , Interleucina-8/metabolismo , Receptores de Interleucina-8B/metabolismo , Microambiente Tumoral , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Humanos , Imuno-Histoquímica , Interleucina-8/genética , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Invasividade Neoplásica/genética , Metástase Neoplásica , Receptores de Interleucina-8B/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Hum Exp Toxicol ; 31(9): 898-904, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22531970

RESUMO

Safrole, a component of piper betle inflorescence, is a documented rodent hepatocarcinogen and inhibits bactericidal activity and the release of superoxide anion (O(2-)) by polymorphonuclear leukocytes (PMNs). In the present study, we investigated the effects of safrole on immune responses, including natural killer (NK) cell cytotoxicity, phagocytic activity and population distribution of leukocytes from normal BALB/c mice. The cells population (cell surface markers) and phagocytosis by macrophages and monocytes from the peripheral blood mononuclear cells (PBMCs) were determined, and NK cell cytotoxicity from splenocytes of mice after oral treatment with safrole was performed using flow cytometric assay. Results indicated that safrole did not affect the weights of body, spleen and liver when compared with the normal mice group. Safrole also promoted the levels of CD11b (monocytes) and Mac-3 (macrophages) that might be the reason for promoting the activity of phagocytosis. However, safrole reduced the cell population such as CD3 (T cells) and CD19 (B cells) of safrole-treated normal mice by oral administration. Furthermore, safrole elevated the uptake of Escherichia coli-labelled fluorescein isothiocyanate (FITC) by macrophages from blood and significantly stimulated the NK cell cytotoxicity in normal mice in vivo. In conclusions, alterations of the cell population (the increase in monocytes and macrophages, respectively) in safrole-treated normal BALB/c mice might indirectly influence the immune responses in vivo.


Assuntos
Antígenos de Diferenciação/imunologia , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Safrol/toxicidade , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Baço/efeitos dos fármacos , Baço/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
6.
Cancer Gene Ther ; 19(4): 263-70, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22301953

RESUMO

Sodium iodide symporter (NIS)-based radionuclide therapy provides an effective means of treating malignant tumors. However, it is sometimes inadequate because of limited effects on radio-resistant tumors, and thus, combination therapies with other therapeutic options have been requested to enhance its efficacy. Human telomerase reverse transcriptase (hTERT) has been reported to be involved in the progression of most cancers and also been viewed as a good candidate for targeting tumor. Application of TERT-specific radionuclide therapies using NIS gene transfer have been reported to treat TERT-positive tumors, but this approach only demonstrated tumor regression rather than eradication. As inhibiting TERT expression by introducing the hTERT-specific shRNA (siTERT) has been suggested as a therapeutic option, we investigated the complementary role of siTERT treatment after the TERT-specific I-131 therapy and its possibility as a novel anticancer therapeutic strategy. Retroviruses containing TERT promoter/NIS for TERT specific Radionuclide therapy and siTERT for TERT targeting antisense therapy were produced. Hep3B cells expressing TERT specific NIS (Hep3B-TERT/NIS) were xenografted into nude mouse and visualized with micro-SPECT/CT for monitoring NIS activity. The levels of hTERT mRNA, protein and its activity were confirmed by RT-PCR, Western blotting and Telomerase repeat amplification protocol assay. Cell proliferation was monitored by MTT assay and induced apoptosis was confirmed by Annexin-V-PI staining. Therapeutic effects of I-131 and/or siTERT were evaluated by clonogenic assay and mouse tumor model. Reduction of hTERT mRNA, protein and TERT activity by siTERT were observed in Hep3B-TERT/NIS cells. The viabilities of the infected cells were significantly decreased to 50% versus siScramble treated controls. The early apoptotic cell population was increased by siTERT. The survival rates of cells treated with siTERT or I-131 alone were 72.4±7.6% and 56.2±5.2%, respectively. However, the survival rate of cells treated with I-131 and siTERT were decreased to 22.1±2.8%. From mouse xenograft model, we also found that the siTERT gene therapy showed synergism to the radioiodine therapy for reducing tumor growth in vivo. Our Results suggested that complementary siTERT gene therapy offers a novel strategy of cancer therapy to improve the therapeutic efficacy of TERT-specific I-131.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Neoplasias/terapia , Interferência de RNA , Simportadores/genética , Telomerase/antagonistas & inibidores , Animais , Apoptose/genética , Linhagem Celular , Proliferação de Células , Terapia Combinada , Regulação Neoplásica da Expressão Gênica , Ordem dos Genes , Inativação Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Humanos , Radioisótopos do Iodo/metabolismo , Camundongos , Camundongos Nus , Neoplasias/diagnóstico por imagem , Neoplasias/genética , Cintilografia , Retroviridae/genética , Simportadores/metabolismo , Telomerase/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Phys Rev Lett ; 109(24): 245003, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23368333

RESUMO

The x-ray intensities made available by x-ray free electron lasers (FEL) open up new x-ray matter interaction channels not accessible with previous sources. We report here on the resonant generation of Kα emission, that is to say the production of copious Kα radiation by tuning the x-ray FEL pulse to photon energies below that of the K edge of a solid aluminum sample. The sequential absorption of multiple photons in the same atom during the 80 fs pulse, with photons creating L-shell holes and then one resonantly exciting a K-shell electron into one of these holes, opens up a channel for the Kα production, as well as the absorption of further photons. We demonstrate rich spectra of such channels, and investigate the emission produced by tuning the FEL energy to the K-L transitions of those highly charged ions that have transition energies below the K edge of the cold material. The spectra are sensitive to x-ray intensity dependent opacity effects, with ions containing L-shell holes readily reabsorbing the Kα radiation.

8.
Rev Sci Instrum ; 79(10): 10E917, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19044572

RESUMO

A high contrast 12.6 keV Kr K alpha source has been demonstrated on the petawatt-class Titan laser facility using strongly clustering Kr gas jet targets. The contrast ratio (K alpha to continuum) is 65, with a competitive ultrashort pulse laser to x-ray conversion efficiency of 10(-5). Filtered shadowgraphy indicates that the Kr K alpha and K beta x rays are emitted from a roughly 1x2 mm(2) emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temperature of 50-70 eV (i.e., mean ionization state 13-16), based on the observed ratio of K alpha to K beta. Kr gas jets provide a debris-free high energy K alpha source for time-resolved diagnosis of dense matter.

9.
J Comp Pathol ; 130(4): 299-305, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15053933

RESUMO

The expression of mRNA encoding interferon-alpha (IFN-alpha) and Mx1 protein was studied, by reverse transcription-polymerase chain reaction and by in-situ hybridization with a non-radioactive digoxigenin-labelled cDNA probe, in formalin-fixed, paraffin wax-embedded lung tissue from pigs experimentally infected with a Korean isolate (North American genotype) of porcine reproductive and respiratory syndrome virus (PRRSV). The animals were examined over a period of 10 days after intranasal inoculation. IFN-alpha and Mx1 protein was detected in the lung at 1 day post inoculation (dpi), the number of positive cells increasing at 7dpi, and rapidly decreasing thereafter. Hybridization signals for IFN-alpha and Mx1 protein were usually associated with inflammation, and in particular with macrophages. Expression of IFN-alpha and Mx1 protein was negative in non-lesional lung of PRRSV-infected pigs and in normal lung from control pigs. There was a good statistical correlation between the number of cells positive for mRNA encoding IFN-alpha and Mx1 protein in the infected lungs (r = 0.95, P< 0.05). The results suggest that the expression of IFN-alpha and Mx1 protein plays a role in the early host defence against PRRSV infection.


Assuntos
Proteínas de Ligação ao GTP/biossíntese , Interferon-alfa/biossíntese , Pulmão/metabolismo , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Doenças dos Suínos/metabolismo , Animais , Hibridização In Situ , Pulmão/patologia , Macrófagos/metabolismo , Proteínas de Resistência a Myxovirus , Síndrome Respiratória e Reprodutiva Suína/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Doenças dos Suínos/imunologia
10.
Br J Cancer ; 87(4): 405-13, 2002 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-12177777

RESUMO

SC142-reactive antigen are highly glycosylated glycoproteins expressed on tissues of gastric and colon cancers but not on normal tissues. Murine SC142 antibody specific for the SC142-reactive antigen has been produced by immunisation with SNU16 stomach cancer cells. However, SC142 antibody has several potential problems such as high immunogenicity and poor tumour penetration owing to their large size. To improve tumour penetration potential in vivo, recombinant single-chain fragments have been produced using the original hybridoma cells as a source of variable heavy- and variable light-chain-encoding antibody genes. The use of the polymerase chain reaction, expression cloning technology and gene expression systems in E. coli has led to the production of SC142 single-chain fragments, which was similar in activity to the SC142 parent antibody confirmed by immunohistochemistry. Analysis by DNA sequencing, SDS-PAGE and Western blotting has demonstrated the integrity of the single-chain fragments. Competitive ELISA showed that SC142 single-chain fragments originated from parent SC142 antibody. BIAcore biosensor binding experiments showed that the SC142 single-chain fragments had an ideal dissociation rate constant as a tumour imaging reagent. These results illustrate the potential application of these novel products as an immunodiagnostic and further immunotherapeutic reagent.


Assuntos
Adenocarcinoma/química , Antígenos de Neoplasias/análise , Neoplasias Gastrointestinais/química , Glicoproteínas de Membrana/análise , Sequência de Aminoácidos , Escherichia coli/genética , Humanos , Hibridomas , Proteínas Recombinantes , Neoplasias Gástricas/química
11.
Aliment Pharmacol Ther ; 16 Suppl 2: 137-44, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11966534

RESUMO

BACKGROUND: RT-PCR amplification of tumour-specific mRNA has been used for the detection of cancer cells in peripheral blood. AIM: To evaluate the characteristics of the tumour specific mRNA species in peripheral blood of stomach cancer patients. METHODS: We analysed CEA, GalNAc-T, MUC-1, c-MET and hTERT mRNA expression in the stomach cancer cell lines and tissues, lymph nodes and peripheral blood of stomach cancer patients using RT-PCR. RESULTS: In RT-PCR analysis of the peripheral blood, 4%, 8%, 21%, 46%, and 100% of stomach cancer patients were positive for CEA, GalNAc-T, c-MET, hTERT and MUC-1 mRNA, respectively, but MUC-1 mRNA was also positive in all normal blood samples. The detection of hTERT mRNA was correlated with poor differentiation (P = 0.01) and lymph node metastasis (P = 0.009). The presence of c-MET mRNA was correlated with T stage (P = 0.025), lymph node metastasis (P = 0.036), distant metastasis (P = 0.031), and stage of the stomach cancer (P = 0.023). CONCLUSIONS: Our study suggest that hTERT mRNA in peripheral blood can be a molecular marker for gastric cancer. We also showed that each molecular marker can be correlated with the clinicopathological features of the patients.


Assuntos
Biomarcadores Tumorais/sangue , Células Neoplásicas Circulantes , RNA Mensageiro/sangue , RNA Neoplásico/sangue , Neoplasias Gástricas/sangue , Biomarcadores Tumorais/genética , Proteínas de Ligação a DNA , Humanos , Metástase Linfática , RNA Mensageiro/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Telomerase/sangue , Telomerase/genética , Células Tumorais Cultivadas
12.
Mol Pharmacol ; 60(5): 972-80, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11641425

RESUMO

The antithyroid drug, methimazole (MMI) is used to treat patients with Graves' hyperthyroidism. The major action of MMI is to inhibit synthesis of thyroid hormone in the thyroid gland. However, MMI also has antioxidant and immunomodulatory effects on thyrocytes and/or immune cells. This study identifies novel antioxidant and immunomodulatory effects of MMI involving the interferon-gamma (IFN-gamma) signaling pathway in thyroid cells. MMI inhibits transcription of the intercellular adhesion molecule-1 (ICAM-1) gene by modulating the function of transcription factor STAT1 (signal transducer and activator of transcription 1), which binds to the IFN-gamma activated site of the ICAM-1 promoter. Furthermore, MMI rapidly eliminates H(2)O(2) produced by IFN-gamma treatment in thyroid cells and thus inhibits the H(2)O(2)-mediated phosphorylation of tyrosine 701 in STAT1. MMI also eliminates H(2)O(2) in vitro. MMI facilitates electron transfer from NADPH to H(2)O(2) using thioredoxin or glutathione, fulfilling a role similar to peroxiredoxin or glutathione peroxidase, respectively. MMI prevents the IFN-gamma and H(2)O(2)-mediated reversible inactivation of phosphatases. These effects inhibit full activation of the IFN-gamma-induced Janus kinase(JAK)/STAT signaling pathway in FRTL-5 thyroid cells. These results may in part explain the antioxidant and immunomodulatory effects of MMI in thyroid cells of Graves' disease patients.


Assuntos
Antioxidantes/farmacologia , Expressão Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Interferon gama/farmacologia , Metimazol/farmacologia , Proteínas , Proteínas Proto-Oncogênicas , Proteínas Repressoras , Glândula Tireoide/efeitos dos fármacos , Fatores de Transcrição , Adjuvantes Imunológicos/farmacologia , Animais , Proteínas de Transporte/biossíntese , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Interações Medicamentosas , Transporte de Elétrons/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Molécula 1 de Adesão Intercelular/biossíntese , Molécula 1 de Adesão Intercelular/genética , Interferon gama/antagonistas & inibidores , Janus Quinase 1 , Janus Quinase 2 , Cinética , Peroxidases/farmacologia , Peroxirredoxinas , Fosforilação/efeitos dos fármacos , Biossíntese de Proteínas , Proteínas Inibidoras de STAT Ativados , Proteínas Tirosina Quinases/metabolismo , Ratos , Fator de Transcrição STAT1 , Fator de Transcrição STAT3 , Transdução de Sinais/fisiologia , Proteína 1 Supressora da Sinalização de Citocina , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina , Glândula Tireoide/citologia , Glândula Tireoide/metabolismo , Transativadores/metabolismo , Tirosina/metabolismo
13.
J Cancer Res Clin Oncol ; 127(9): 551-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11570576

RESUMO

PURPOSE: To identify a new tumor-associated antigen, a monoclonal antibody, SC142, was produced by immunizing mice with a stomach cancer cell line. The tumor specificity of mAb SC142 was studied by immunohistochemical staining, and the biochemical characteristics of this new gastrointestinal tumor-associated antigen were also studied. METHODS: The expression of SC142-reactive antigen was investigated in various cancers by immunohistochemical staining. The SC142-reactive antigen was characterized by immunoblotting, sodium metaperiodate treatment assay, O-glycanase digestion assay, and lectin binding assay. RESULTS: The SC142-reactive antigen was highly expressed in 78% of gastric cancers (29/37) and 87% of colon cancers (27/31). No normal colon or stomach tissues remote from the tumor were positive for the antigen. The antibody also reacted with other tumors of epithelial origin such as lung squamous cell cancer (2/4), breast ductal cancer (2/20), bladder transitional cell carcinoma (4/6), and uterine cancer (3/16). Western blot analysis of the antigen revealed glycoprotein(s) which migrated as a smear ranging from the origin of the gel to about the 80 kDa region. The reactivity of this antigen with SC142 was reduced by sodium metaperiodate treatment or O-glycanase digestion, but not by N-glycanase, suggesting that the epitope is an O-glycan. In lectin-binding assay, this antigen reacted only with wheat germ agglutinin but not with Ricinus communis agglutinin, Datura stramonium agglutinin, and Sambucus nigra agglutinin. CONCLUSIONS: Our findings indicate that the antigen defined by SC142 is a tumor-associated antigen that could differentiate the gastrointestinal cancer cells from the normal cells. Therefore, SC142 may become a valuable tool for the immunohistochemical diagnosis and tumor immunoscintigraphy of the gastrointestinal cancer patients.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias Gastrointestinais/imunologia , Mucinas/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Reações Antígeno-Anticorpo , Antígenos de Neoplasias/metabolismo , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Neoplasias Gastrointestinais/metabolismo , Neoplasias Gastrointestinais/patologia , Hexosaminidases/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Mucinas/metabolismo , Polissacarídeos/imunologia , Polissacarídeos/metabolismo
14.
Toxicol Sci ; 63(1): 99-106, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11509749

RESUMO

To investigate the disease process of pneumoconiosis induced by welding-fume exposure, a lung fibrosis model was established by building a stainless steel arc welding fume generation system and exposing male Sprague-Dawley rats for 90 days. The rats were exposed to welding fumes with concentrations of 57-67 mg/m3 (low dose) and 105-118 mg/m3 (high dose) total suspended particulates for 2 h per day in an inhalation chamber for 90 days. The concentrations of the main metals, Fe, Mn, Cr, and Ni, were measured in the welding fumes, plus the gaseous compounds, including nitrous gases and ozone, were monitored. During the exposure period, the animals were sacrificed after the initial 2-h exposure and after 15, 30, 60, and 90 days. Histopathological examinations were conducted on the animals' upper respiratory tract, including the nasal pathway and conducting airway, plus the gas exchange region, including the alveolar ducts, alveolar sacs, and alveoli. When compared to the control group, the lung weights did not increase significantly in the low-dose group, yet in the high-dose group there was a significant increase from day 15 to day 90. The histopathological examination combined with fibrosis-specific staining (Masson's trichrome) indicated that the lungs in the low-dose group did not exhibit any progressive fibrotic changes. Whereas, the lungs in the high-dose group exhibited early delicate fibrosis from day 15, which progressed into the perivascular and peribronchiolar regions by day 30. Interstitial fibrosis appeared at day 60 and became prominent by day 90, along with the additional appearance of pleural fibrosis. Accordingly, it would appear that a significant dose of welding-fume exposure was required to induce lung fibrosis.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Fibrose Pulmonar/induzido quimicamente , Aço Inoxidável , Administração por Inalação , Animais , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Gases/análise , Exposição por Inalação , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Metais Pesados/análise , Tamanho do Órgão/efeitos dos fármacos , Fibrose Pulmonar/patologia , Ratos , Ratos Sprague-Dawley , Organismos Livres de Patógenos Específicos , Fatores de Tempo , Soldagem
15.
Mol Cells ; 12(3): 398-402, 2001 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11804341

RESUMO

Recombinant immunotoxin for the treatment of cancer was made by connecting toxins to 'carcinoma-specific' antibodies that selectively bind to cancer cells, then kills them without harming the normal cells. The divalent recombinant immunotoxin, [B3(Fab)-ext-PE38]2, is a derivative of B3(Fab)-PE38. B3(Fab)-PE38 was made by fusing the Fab domain of the monoclonal antibody (MAb) B3 to PE38, a truncated mutant form of Pseudomonas exotoxin (PE). In this study, B3(Fab)-ext-PE38 was constructed, which has the hinge region of the B3(Fab)-PE38 extended with the peptide extension, G4C(G4S)2, and connected to the C3 connector. The Cys residue of the extension peptide chain makes the disulfide bond between the two Fab domains. The extension sequence (ext) makes the dimerization of B3(Fab)-ext-PE38 easier to form the divalent immunotoxin, because it decreases the steric hindrance between the two PE38s. The constructed genes were expressed in E. coli as inclusion bodies. Polypeptides that were obtained from the inclusion body were refolded, and the active forms were purified. The ID50 values of the divalent molecule, [B3(Fab)-ext-PE38]2, were about 4 ng/ml on A431 cell lines, about 1 ng/ml on CRL1739 cell lines, and 5 ng/ml on MCF-7 cell lines. The [B3(Fab)-ext-PE38]2 showed about a 12-fold higher cytotoxicity on CRL1739 cell lines than B3(scFv)-PE40 did.


Assuntos
Proteínas de Bactérias/genética , Imunotoxinas/genética , Proteínas Recombinantes de Fusão/genética , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Testes Imunológicos de Citotoxicidade , Imunotoxinas/imunologia , Imunotoxinas/metabolismo , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Células Tumorais Cultivadas
16.
Cancer Biother Radiopharm ; 16(5): 439-47, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11776761

RESUMO

The mistletoe lectins are major active components in the extract of European mistletoes that have been widely used in adjuvant chemotherapy of cancer. This study was performed to investigate the mechanism of anticancer and antimetastatic activity of the purified Korean mistletoe lectin (Viscum album L. coloratum agglutinin, VCA). C57BL6 mice inoculated with B16-BL6 melanoma cells and treated with VCA were assessed for survival and metastasis. The induction of apoptosis of B16-BL6 cells by VCA was investigated by morphological changes, DNA fragmentation characteristics, and cell cycle analysis. The antiangiogenic activity of VCA was also measured by the CAM (choriallantoic membrane) assay. Length of survival of mice was increased and lung metastasis was inhibited by VCA. Treatment of cells with VCA resulted in growth suppression, nuclear morphological changes, DNA fragmentation, and an increased fraction of cells in sub-G1 consistent with apoptosis. Antiangiogenesis of VCA was assessed by CAM assay, where vessel growth induced by fat emulsion was decreased. These results suggest that VCA inhibits tumor growth and metastasis by increasing apoptosis and inhibiting angiogenesis.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Preparações de Plantas , Proteínas de Plantas , Toxinas Biológicas/uso terapêutico , Alantoide/irrigação sanguínea , Alantoide/efeitos dos fármacos , Inibidores da Angiogênese/farmacologia , Animais , Ciclo Celular/efeitos dos fármacos , Embrião de Galinha , Córion/irrigação sanguínea , Córion/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/patologia , Melanoma Experimental/secundário , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Inativadoras de Ribossomos Tipo 2
17.
Arch Pharm (Weinheim) ; 334(11): 357-60, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11822173

RESUMO

The 4-anilinoquinazoline PD 153035 (1) is a potential antitumor agent which acts by inhibiting tyrosine kinase activity of epidermal growth factor receptor (EFGR) via competitive binding at the ATP site of enzyme. A series of cyclic analogues of PD 153035 bearing the 1,4-dioxane ring was prepared by reaction of 6-chloro derivative 5 with several aniline nucleophiles. These were evaluated for their ability to inhibit the EGFR kinase and the growth of primary human tumor cell cultures. All of the new 4-anilinoquinazolines exhibited less potency than PD 153035 against EGFR kinase. However, compounds 2b, 2c, 2e, 2g, and 2h showed higher inhibitory activities than PD 153035 against the growth of A431 tumor cell line. The compound 2b containing 3-chloroaniline ring was as potent as PD 153035 against EGFR kinase and showed about 5.4-fold better potency than PD153035 in the inhibition of growth of A431 cell line with good selectivity.


Assuntos
Antineoplásicos/síntese química , Quinazolinas/farmacologia , Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Dioxanos , Receptores ErbB/antagonistas & inibidores , Humanos , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinazolinas/síntese química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
18.
J Hum Ergol (Tokyo) ; 30(1-2): 229-33, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14564887

RESUMO

This study examined the effects of shiftwork on the cardiovascular system. The blood pressure (BP) and heart rate variability (HRV) of 134 male workers, who worked 8-hour shifts with rapid rotation of shifts at 3-day intervals, were examined for all the three shifts. In addition, the job stress was measured by Karasek's JCQ 49-item questionnaire and the circadian type was assessed by the morningness-eveningness questionnaire. The smoking and alcohol drinking habits, marital status and past medical history were also obtained. The method of analyzing the measured data based on a mixed model was used to illustrate the association between the shiftwork duration and the BP or HRV. The average age of workers was 29 years (between 25-44). Among them, 77.9% were current smokers, 50% showed the passive type of job strain in Karasek's model. The mean shiftwork duration was 5.21 years (range 5.4 months--10 years). In the circadian type, none of them belonged to a definitely morning type or a definitely evening type. In the multivariate analysis adjusted by age, job strain, shift, circadian rhythm and smoking, the blood pressure showed significantly increasing trends according to shiftwork duration in both the systolic and diastolic BP. The heart rate variability also showed a significantly decreasing trend according to the shiftwork duration in both the parasympathetic and sympathetic functions (p < 0.05). These results suggests that there are negative health effects arising from shiftwork on the cardiovascular system.


Assuntos
Nível de Alerta/fisiologia , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Admissão e Escalonamento de Pessoal , Tolerância ao Trabalho Programado/fisiologia , Adulto , Sistema Cardiovascular/fisiopatologia , Ritmo Circadiano/fisiologia , Eletrocardiografia Ambulatorial , Humanos , Masculino
19.
Hybridoma ; 19(5): 369-74, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11128026

RESUMO

Heat shock protein 70 (hsp 70) plays major roles in apoptosis prevention and thermotolerance as well as molecular chaperoning. It is also expressed on the surface of human tumor cells, but not on normal cells, suggesting that hsp70 may be some tumor-associated antigen. To investigate the diverse functions of the protein species, various types of transgenic mice or cell models overexpressing human hsp70 have been made. In these models a monoclonal antibody (MAb) specific for the human hsp70 is highly desirable to distinguish the human from the endogenous mouse hsp70. It proved difficult to make this species-specific MAb, because the hsp70 homologues are members of a family of highly conserved, abundant, and ubiquitous proteins expressed in organisms ranging from bacteria to humans. In the present study, we prepared four MAbs against human hsp70. Three, HD 5, HD 7 and HD 11, recognize human and mouse hsp70. One, though, HD 8, recognizes human hsp70, but not mouse hsp70. By Western blot analysis of hsp70 deletion mutants, the epitope of the HD 8 MAb was determined as the 585-616 amino acid region of the human hsp70, a region with relatively low homology to mouse hsp70.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Proteínas de Choque Térmico HSP70/imunologia , Animais , Baculoviridae/genética , Western Blotting , Reações Cruzadas , Feminino , Deleção de Genes , Proteínas de Choque Térmico HSP70/genética , Humanos , Hibridomas/imunologia , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Testes de Precipitina , Células Tumorais Cultivadas
20.
Int Rev Immunol ; 19(6): 633-64, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11129119

RESUMO

In this report we summarize evidence to support a model for the development of Graves' disease. The model suggests that Graves' disease is initiated by an insult to the thyrocyte in an individual with a normal immune system. The insult, infectious or otherwise, causes double strand DNA or RNA to enter the cytoplasm of the cell. This causes abnormal expression of major histocompatibility (MHC) class I as a dominant feature, but also aberrant expression of MHC class II, as well as changes in genes or gene products needed for the thyrocyte to become an antigen presenting cell (APC). These include increased expression of proteasome processing proteins (LMP2), transporters of antigen peptides (TAP), invariant chain (Ii), HLA-DM, and the co-stimulatory molecule, B7, as well as STAT and NF-kappaB activation. A critical factor in these changes is the loss of normal negative regulation of MHC class I, class II, and thyrotropin receptor (TSHR) gene expression, which is necessary to maintain self-tolerance during the normal changes in gene expression involved in hormonally-increased growth and function of the cell. Self-tolerance to the TSHR is maintained in normals because there is a population of CD8- cells which normally suppresses a population of CD4+ cells that can interact with the TSHR if thyrocytes become APCs. This is a host self-defense mechanism that we hypothesize leads to autoimmune disease in persons, for example, with a specific viral infection, a genetic predisposition, or even, possibly, a TSHR polymorphism. The model is suggested to be important to explain the development of other autoimmune diseases including systemic lupus or diabetes.


Assuntos
Doença de Graves/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Regulação da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Sistema Imunitário/imunologia , Tolerância a Antígenos Próprios/imunologia , Timo/citologia , Tireoidite Autoimune/imunologia , Tireotropina/imunologia
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