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1.
Dis Esophagus ; 29(2): 107-15, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25168378

RESUMO

UNLABELLED: The stem cell compartment in the esophageal epithelium is possibly located in the basal layer. We have identified significant expression of Smad2/3, phosphorylated at specific linker threonine residues (pSmad2/3L-Thr), in the epithelial cells of murine stomach and intestine, and have suggested that these cells are epithelial stem cells. In this study, we explore whether pSmad2/3L-Thr could serve as a biomarker for esophageal stem cells. We examined esophageal tissues from normal C57BL/6 mice and those with esophagitis. Double immunofluorescent staining of pSmad2/3L-Thr with Ki67, CDK4, p63, or CK14 was performed. After immunofluorescent staining, we stained the same sections with hematoxylin-eosin and observed these cells under a light microscope. We used the 5-bromo-2-deoxyuridine (BrdU) labeling assay to examine label retention of pSmad2/3L-Thr immunostaining-positive cells. We collected specimens 5, 10, 15 and 20 days after repeated BrdU administrations and observed double immunofluorescent staining of pSmad2/3L-Thr with BrdU. In the esophagus, pSmad2/3L-Thr immunostaining-positive cells were detected in the basal layer. These cells were detected between Ki67 immunostaining-positive cells, but they were not co-localized with Ki67. pSmad2/3L-Thr immunostaining-positive cells showed co-localization with CDK4, p63, and CK14. Under a light microscope, pSmad2/3L-Thr immunostaining-positive cells indicated undifferentiated morphological features. Until 20 days follow-up period, pSmad2/3L-Thr immunostaining-positive cells were co-localized with BrdU. pSmad2/3L-Thr immunostaining-positive cells significantly increased in the regeneration phase of esophagitis mucosae, as compared with control mice (esophagitis vs. CONTROL: 6.889 ± 0.676/cm vs. 4.293 ± 0.659/cm; P < 0.001). We have identified significant expression of pSmad2/3L-Thr in the specific epithelial cells of murine esophagi. We suggest that these cells are slow-cycling epithelial stem-like cells before re-entry to the cell cycle.


Assuntos
Proteínas de Ciclo Celular/análise , Ciclo Celular , Esôfago/citologia , Proteína Smad2/análise , Proteína Smad3/análise , Células-Tronco/química , Treonina , Animais , Pontos de Checagem do Ciclo Celular , Quinase 4 Dependente de Ciclina/análise , Células Epiteliais/química , Mucosa Esofágica/citologia , Mucosa Esofágica/patologia , Esofagite/metabolismo , Esofagite/patologia , Esôfago/patologia , Antígeno Ki-67/análise , Camundongos , Camundongos Endogâmicos C57BL , Fosfoproteínas/análise , Fosforilação , Coloração e Rotulagem , Células-Tronco/citologia , Transativadores/análise
2.
J Viral Hepat ; 17(7): 488-92, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19840366

RESUMO

Thrombocytopenic patients with chronic hepatitis C virus (HCV) infection are poor candidates for antiviral treatment with interferon (IFN), but no standard treatment for thrombocytopenia has yet been established. We evaluated the safety of splenectomy and its efficacy for the initiation and continuation of antiviral therapy. From March 2003 to April 2006, 10 patients (mean age 62.5 years) with HCV-related cirrhosis, low platelet count (<==106 000/mm(3)) and splenomegaly (spleen size >==10 cm) underwent splenectomy. Platelet counts significantly increased at 4-8 weeks after splenectomy [pre: 64 200 +/- 6900/mm(3)vs post 209 000 +/- 40 600/mm(3) (P = 0.004)]. No severe operative complications were observed. All patients subsequently received antiviral therapy. Of the eight patients who were infected with HCV genotype 1 and had a high viral load (>==100 KIU/mL), four received combination therapy with pegylated IFNalpha-2b plus ribavirin, and the other four received standard IFNalpha-2b plus ribavirin. One patient infected with HCV genotype 2 and another with HCV genotype 1 and a low viral load (<100 KIU/mL) were treated with pegylated IFNalpha-2a. Six patients achieved sustained virologic response (SVR). Among four patients who failed to achieve SVR, one was given retreatment with pegylated IFN plus ribavirin, and the other three received low-dose long-term IFN therapy. Although this study was small, the treatment results were similar to those for patients without thrombocytopenia and suggested that splenectomy would not reduce the antiviral efficacy of IFNalpha-based treatment.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Esplenectomia , Esplenomegalia/cirurgia , Trombocitopenia/terapia , Idoso , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes , Ribavirina/uso terapêutico , Resultado do Tratamento , Carga Viral
3.
Clin Exp Allergy ; 39(1): 89-100, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19055649

RESUMO

UNLABELLED: BACKGROUND" Human thymic stromal lymphopoietin (TSLP) is expressed in the human asthmatic lung and activates dendritic cells (DCs) to strongly induce proallergic T-helper type 2 (Th2) cell responses, suggesting that TSLP plays a critical role in the pathophysiology of human asthma. Th2 cells are predominantly involved in mild asthma, whereas a mixture of Th1 and Th2 cells with neutrophilic inflammation, probably induced by Th17, affects more severe asthmatic disease. Exacerbation of asthmatic inflammation is often triggered by airway-targeting RNA viral infection; virus-derived double-stranded RNA, Toll-like receptor (TLR)3 ligand, activates bronchial epithelial cells to produce pro-inflammatory mediators, including TSLP. OBJECTIVE: Because TSLPR-expressing DCs express TLR3, we examined how the relationship between TSLP and TLR3 ligand stimulation influences DC activation. METHODS: CD11c(+)DCs purified from adult peripheral blood were cultured in TLR ligands containing media with or without TSLP and then co-cultured with allogeneic naïve CD4(+)T cells. RESULTS: CD11c(+) DCs responded to a combination of TSLP and TLR3 ligand, poly(I : C), to up-regulate expression of the functional TSLP receptor and TLR3. Although TSLP alone did not induce IL-23 production by DCs, poly(I : C) alone primed DCs for the production of IL-23, and a combination of TSLP and poly(I : C) primed DCs for further production of IL-23. The addition of poly(I : C) did not inhibit TSLP-activated DCs to prime naïve CD4(+) T cells to differentiate into inflammatory Th2 cells. Furthermore, DCs activated by a combination of TSLP and poly(I : C) primed more naïve CD4(+) T cells to differentiate into Th17-cytokine-producing cells with a central memory T cell phenotype compared with DCs activated by poly(I : C) alone. CONCLUSIONS: These results suggest that through DC activation, human TSLP and TLR3 ligands promote differentiation of Th17 cells with the central memory T cell phenotype under Th2-polarizing conditions.


Assuntos
Diferenciação Celular , Citocinas/metabolismo , Memória Imunológica , Interleucina-17/metabolismo , Ligantes , Linfócitos T Auxiliares-Indutores/citologia , Receptor 3 Toll-Like/metabolismo , Adulto , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Fenótipo , Células Th2/imunologia , Linfopoietina do Estroma do Timo
4.
Endoscopy ; 41(10): 902-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19750452

RESUMO

There is little guidance on the performance of endoscopic retrograde cholangiopancreatography (ERCP) in patients with previous pancreatoduodenectomy. We reviewed techniques for ERCP with a conventional endoscope and assessed its value in 10 patients with previous pancreatoduodenectomy (15 ERCPs). After exploration of the surgical reconstruction, we used a front-viewing endoscope, and we used a small firm pillow under the abdomen and hand compression for preventing loop formation. Successful insertion to the ductal anastomoses and biliary cannulation were achieved in 13 / 15 procedures (87 %). In 6 procedures where we attempted pancreatic cannulation, we could not identify the pancreatojejunostomy, but after spraying contrast around the suspected location of the ductal anastomosis we obtained a pancreatogram in 4 / 6 procedures (67 %). Endoscopic biliary interventions were successful in 6 / 7 procedures (86 %). No complications were encountered. Use of appropriate techniques makes ERCP with a conventional endoscope feasible, effective, and safe in patients with previous pancreatoduodenectomy. Endoscopic therapy can be performed successfully in the bile duct, but has limited value regarding the pancreatic duct.


Assuntos
Doenças Biliares/cirurgia , Colangiopancreatografia Retrógrada Endoscópica/instrumentação , Colangiopancreatografia Retrógrada Endoscópica/métodos , Pancreaticoduodenectomia/instrumentação , Pancreaticoduodenectomia/métodos , Idoso , Duodenoscópios , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
J Vet Pharmacol Ther ; 32(3): 264-70, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19646091

RESUMO

We investigated the effect of bradykinin (BK) on isolated equine basilar arterial rings with and without endothelium. BK induced concentration-dependent contraction of resting arterial rings and no relaxation when the rings were precontracted by prostaglandin F(2alpha). The maximal response and pD(2) value were 161.2 +/- 28.1% (to 60 mm KCl-induced contraction) and 8.24 +/- 0.25 respectively. The cumulative concentration-response curve for BK was not shifted to the right by des-Arg(9)-[Leu(8)]-BK (a B(1)-receptor antagonist), HOE140 (a B(2)-receptor antagonist) or NPC567 (another B(2)-receptor antagonist). In four of six basilar arteries, NPC567 induced concentration-dependent contraction. Indomethacin (a cyclooxygenase inhibitor), nordihydroguaiaretic acid (a lipoxygenase inhibitor), quinacrine (a phospholipase A(2) inhibitor), tetrodotoxin (a selective blocker of Na(+) channels), guanethidine (a nor-adrenergic neuron blocking drug), phentolamine (an alpha-adrenoceptor antagonist), Nomega-nitro-L-arginine (L-NNA, a nitric oxide (NO) synthase inhibitor) and endothelial denudation did not affect the BK-induced contraction. L-NNA and indomethacin induced contraction and relaxation under resting vascular tone respectively. These results suggest that endothelial cells are not involved in BK-induced contraction and that the contraction is not mediated via activation of known B(1) and B(2) receptors. Arachidonic acid metabolites and neurotransmitters like norepinephrine and NO might not play a role in BK-induced contraction in equine basilar artery.


Assuntos
Artéria Basilar/efeitos dos fármacos , Bradicinina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Cavalos/fisiologia , Vasodilatadores/farmacologia , Matadouros , Análise de Variância , Animais , Artéria Basilar/fisiologia , Dinoprosta/administração & dosagem , Endotélio Vascular/fisiologia , Feminino , Masculino , Suínos
6.
Clin Exp Immunol ; 154(1): 98-106, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18727630

RESUMO

Human thymic stromal lymphopoietin (TSLP) promotes CD4(+) T-cell proliferation both directly and indirectly through dendritic cell (DC) activation. Although human TSLP-activated DCs induce CD8(+) T-cell proliferation, it is not clear whether TSLP acts directly on CD8(+) T cells. In this study, we show that human CD8(+) T cells activated by T-cell receptor stimulation expressed TSLP receptor (TSLPR), and that TSLP directly enhanced proliferation of activated CD8(+) T cells. Although non-stimulated human CD8(+) T cells from peripheral blood did not express TSLPR, CD8(+) T cells activated by anti-CD3 plus anti-CD28 did express TSLPR. After T-cell receptor stimulation, TSLP directly enhanced the expansion of activated CD8(+) T cells. Interestingly, using monocyte-derived DCs pulsed with a cytomegalovirus (CMV)-specific pp65 peptide, we found that although interleukin-2 allowed expansion of both CMV-specific and non-specific CD8(+) T cells, TSLP induced expansion of only CMV-specific CD8(+) T cells. These results suggest that human TSLP directly enhances expansion of CD8(+) T cells and that the direct and indirect action of TSLP on expansion of target antigen-specific CD8(+) T cells may be beneficial to adoptive cell transfer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Citocinas/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/virologia , Proliferação de Células , Técnicas de Cocultura , Citocinas/análise , Citomegalovirus/imunologia , Células Dendríticas/imunologia , Citometria de Fluxo , Humanos , Interleucina-2/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Ativação Linfocitária/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfopoietina do Estroma do Timo
7.
AJNR Am J Neuroradiol ; 28(6): 1179-84, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17569984

RESUMO

BACKGROUND AND PURPOSE: The inferior petrosal sinus (IPS) is the main transvenous access route used to examine or treat lesions involving the cavernous sinus. To carry out these procedures successfully, one must have a detailed knowledge of the anatomy of the venous system around the junction of the IPS and the internal jugular vein (IJV). MATERIALS AND METHODS: Eighty-three sides in 63 patients (26 men, 37 women; mean, 56.5 years of age) were examined by using 3D rotational venography (3DRV). RESULT: The drainage patterns of the IPS could be classified into the following 6 types, with emphasis on the level of IPS-IJV junction: type A, the IPS drains into the jugular bulb in 1/83 sides (1.2%); type B, the IPS drains into the IJV at the level of the extracranial opening of the hypoglossal canal in 29/83 sides (34.9%); type C, the IPS drains into the lower extracranial IJV in 31/83 sides (37.3%); type D, the IPS forms a plexus and has multiple junctions to the IJV near the jugular foramen in 5/83 sides (6.0%); type E, the IPS drains directly into the vertebral venous plexus (VVP) with no connection to the IJV in 3/83 sides (3.6%); and type F, the IPS is absent in 14/83 sides (16.9%). Each type is also characterized by the way of anastomosis with the VVP. CONCLUSION: This classification seemed to be rational from the embryologic viewpoint, and it may be useful in establishing treatment strategies that involve endovascular manipulation via the IPS.


Assuntos
Cavidades Cranianas/anatomia & histologia , Cavidades Cranianas/diagnóstico por imagem , Imageamento Tridimensional/métodos , Flebografia/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Rotação , Sensibilidade e Especificidade
8.
J Clin Neurosci ; 14(1): 65-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17092723

RESUMO

We report a dural arteriovenous fistula (AVF) that developed at a site on the midline dorsal surface of the dura mater that had been damaged by repeated lumbar punctures. A 61-year-old male patient had undergone repeated lumbar punctures and discectomy for severe lumbago 40 years before the present admission. After surgery, the lumbago symptoms resolved. However, 30 years after the operation, he started to experience dysaesthesia, motor weakness in both legs, and urinary disturbance. Physical examination revealed bilateral leg weakness, diminished deep tendon reflexes in the patellar and Achilles tendons bilaterally, and decreased superficial sensation below L1. Magnetic resonance imaging revealed swelling with intramedullary high intensity and multiple flow voids around the conus and spinal cord on T(2)-weighted images, and adhesive arachnoiditis. Spinal angiography revealed an AVF between the left lateral sacral artery and the S1 radicular vein at the site of the previous operation. Surgery was conducted to carry out excision of the dural AVF at the shunting point, the arterialized intradural vein, and lysis of the arachnoiditis. This case of dural AVF may have been caused by repeated lumbar punctures.


Assuntos
Fístula Arteriovenosa/etiologia , Fístula Arteriovenosa/patologia , Dura-Máter/patologia , Complicações Pós-Operatórias/patologia , Fístula Arteriovenosa/cirurgia , Angiografia Cerebral , Humanos , Laminectomia/efeitos adversos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Compressão da Medula Espinal/etiologia , Punção Espinal/efeitos adversos
9.
J Natl Cancer Inst ; 70(6): 1097-102, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6574279

RESUMO

Mitonafide (5-nitro-2-(2-dimethylaminoethyl)-benzo- [de]isoquinoline-1,3-dione hydrochloride), a new candidate as an anticancer or antiviral agent, inhibited the incorporation of DNA precursors into the acid-insoluble fractions of cultured Chinese hamster ovary (CHO) cells and also into CHO cells made permeable (i.e., "permeabilized") that were supplemented with ATP and deoxynucleoside triphosphates. Mitonafide enhanced the degradation of previously incorporated [3H]thymidine and increased the amount of DNA recovered in fractions containing single-stranded DNA after alkaline denaturation and hydroxyapatite chromatography. At concentrations of 0.01 and 1.0 microM, respectively, mitonafide increased the frequency of sister chromatid exchanges and chromosome aberrations in CHO cells. The inhibition of DNA synthesis in a permeabilized cell system suggested that mitonafide acted on the DNA-synthesizing apparatus without requiring metabolic conversion and interfered with DNA synthesis independent of the cellular metabolism of DNA precursors. Mitonafide induced DNA strand breaks and chromosome abnormalities in cultured cells.


Assuntos
Aberrações Cromossômicas , Troca Genética/efeitos dos fármacos , DNA de Cadeia Simples/análise , DNA/biossíntese , Imidas , Isoquinolinas/toxicidade , Troca de Cromátide Irmã/efeitos dos fármacos , Animais , Linhagem Celular , Cricetinae , Cricetulus , Feminino , Naftalimidas , Ovário , Timidina/metabolismo
10.
Cancer Res ; 43(5): 1951-6, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6339045

RESUMO

Three analogues of aminoalkylamino-substituted anthraquinone derivatives, namely, 1,4-dihydroxy-5,8-bis(((2-[(2-hydroxyethyl)amino]ethyl)amino))-9,10-anthracenedione (DHAQ), 1-hydroxy-5,8-bis(((2-[(2-hydroxyethyl)amino]ethyl)amino))-9,10-anthracenedione (HAQ), and 1,4-bis(((2-[(2-hydroxyethyl)amino]ethyl)amino))-9,10-anthracenedione (AQ), were chosen with respect to the number of hydroxyl groups on the aromatic ring. DHAQ showed about 100 times more potent antiproliferative activity on cultured mouse L-cells than did AQ; HAW showed intermediate activity. This antiproliferative activity was correlated with their inhibitory effect on DNA synthesis in culture. When their inhibitory effect on DNA synthesis was conducted in a permeabilized L-cell assay, all compounds were inhibitory; the order of potency was DHAQ greater than HAQ greater than AQ. The same order of potency was also observed in calf thymus DNA and Escherichia coli DNA polymerase I system. Their inhibitory effect in the latter system was correlated with the drug:DNA molar ratio, and not with drug:enzyme ratio. Comparative uptake of the drugs by intact L-cells showed the highest uptake of DHAQ followed by those of HAQ and AQ. The large differences in their uptake by intact cells became minimal when cells were rendered permeable to exogenous materials or when nuclei were used. Hence, these studies revealed that the hydroxyl group on the aromatic ring of the compounds influenced their biological activity not only by potentiating drug-target interaction but also by drug uptake into cells.


Assuntos
Antraquinonas/farmacologia , DNA/biossíntese , Células L/metabolismo , Animais , Antraquinonas/metabolismo , Bovinos , Divisão Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , DNA Polimerase I/metabolismo , Depressão Química , Escherichia coli/enzimologia , Camundongos , Timo/metabolismo
11.
Magnes Res ; 18(3): 155-62, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16259375

RESUMO

Since endotoxin-induced vascular hyporeactivity to phenylephrine is enhanced in Mg-deficient rats, this study was designed to determine whether endotoxin directly enhances nitric oxide (NO) production in thoracic aortas isolated from Mg-deficient rats in vitro. Thoracic aortas isolated from Mg-deficient and control rats were cultured for 6 h with or without endotoxin (LPS). LPS (0.01-1.0 microg) increased NO production in a concentration-dependent manner. NO production in the presence of 0.1 and 1.0 microg/mL LPS was significantly higher in Mg-deficient rat aortas compared to aortas from control rats. The enhanced NO production was not significantly affected by endothelium-denudation. LPS-stimulated NO production was fully inhibited by a selective iNOS inhibitor, 1400W (0.1, 1.0 microM), in control rat aortas, but in Mg-deficient rat aortas inhibition by 1400W was only partial. A similar inhibitory effect was observed with anti-CD14 and anti-TLR4 antibodies. These results suggest that endotoxin enhances NO production in Mg-deficient rat aortas directly, and that endotoxin receptors might, at least in part, contribute to this enhancement.


Assuntos
Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Lipopolissacarídeos/farmacologia , Magnésio/metabolismo , Óxido Nítrico/metabolismo , Animais , Anticorpos/metabolismo , Endotélio Vascular/metabolismo , Técnicas In Vitro , Receptores de Lipopolissacarídeos/imunologia , Masculino , Ratos , Ratos Wistar
12.
Neuroscience ; 310: 188-97, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26363152

RESUMO

Hearing loss of patients with enlargement of the vestibular aqueduct (EVA) can fluctuate or progress, with overall downward progression. The most common detectable cause of EVA is mutations of SLC26A4. We previously described a transgenic Slc26a4-insufficient mouse model of EVA in which Slc26a4 expression is controlled by doxycycline administration. Mice that received doxycycline from conception until embryonic day 17.5 (DE17.5; doxycycline discontinued at embryonic day 17.5) had fluctuating hearing loss between 1 and 6 months of age with an overall downward progression after 6 months of age. In this study, we characterized the cochlear functional and structural changes underlying irreversible hearing loss in DE17.5 mice at 12 months of age. The endocochlear potential was decreased and inversely correlated with auditory brainstem response thresholds. The stria vascularis was thickened and edematous in ears with less severe hearing loss, and thinned and atrophic in ears with more severe hearing loss. There were pathologic changes in marginal cell morphology and gene expression that were not observed at 3 months. We conclude that strial dysfunction and degeneration are the primary causes of irreversible progressive hearing loss in our Slc26a4-insufficient mouse model of EVA. This model of primary strial atrophy may be used to explore the mechanisms of progressive hearing loss due to strial dysfunction.


Assuntos
Proteínas de Transporte de Ânions/deficiência , Proteínas de Transporte de Ânions/genética , Perda Auditiva/etiologia , Estria Vascular/patologia , Doenças Vestibulares/complicações , Doenças Vestibulares/genética , Estimulação Acústica , Animais , Limiar Auditivo/fisiologia , Morte Celular/genética , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico/genética , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Regulação da Expressão Gênica/genética , Genótipo , Células Ciliadas Auditivas/patologia , Perda Auditiva/genética , Perda Auditiva/fisiopatologia , Canal de Potássio KCNQ1/genética , Canal de Potássio KCNQ1/metabolismo , Camundongos , Camundongos Transgênicos , Mutação/genética , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Transportadores de Sulfato , Aqueduto Vestibular/patologia
13.
Int J Radiat Oncol Biol Phys ; 26(3): 433-43, 1993 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8514541

RESUMO

PURPOSE: A new hypoxic cell sensitizer has been synthesized; this is a 2-nitroimidazole nucleoside analog having erythritol as a sugar moiety at the N-1 position of the imidazole ring (RP-343). Its possibility as a potent hypoxic cell sensitizer was compared with those of RP-170 and etanidazole. METHODS AND MATERIALS: Radiosensitization was tested in two murine tumors, EMT6 using in vitro and in vivo-in vitro assays and SCCVII using growth delay and TCD50 assays. Pharmacokinetic study was performed in Balb/c mice bearing EMT6 tumors and in Beagle dogs. LD50 of each sensitizer was obtained with ICR mice. RESULTS: As might be expected from the almost identical electron affinities of the three sensitizers, they were equally effective against hypoxic EMT6 cells in vitro. While having the lowest partition coefficient (0.035), RP-343 exhibited almost equally effective distribution to tumors and sensitizing radiation activity. An intravenous (i.v.) injection of 100 mg/kg of RP-343, RP-170 and etanidazole showed an almost equal sensitizer enhancement ratio (SER) of about 1.4 to solid EMT6 tumor under in vivo-in vitro assay and a virtually equal SER of 1.33-1.44 to solid SCCVII tumor under both tumor growth delay assay and TCD50 assay. A great advantage of RP-343 over RP-170 and etanidazole is its very much lower toxicity; their LD50 in mice were > 6.0, 4.3 and 4.8 g/kg, respectively, on i.v. injection. The lower toxicity of RP-343 was supported by its lower concentrations in the brain; the RP-343 AUC for brain was 0.43 times that of RP-170. Three indices were selected to compare the three nitroimidazoles. SER at 5% LD50 doses of RP-343, RP-170 and etanidazole was 1.66, 1.59 and 1.56. At the same toxicity levels, RP-343 was found to have better sensitization of solid tumors over both etanidazole and RP-170. The maximum tumor concentration/AUC for brain (Cmax,tumor/AUCbrain) ratios for RP-343 and RP-170 were 9.62 and 3.98. CONCLUSIONS: This extremely high ratio of RP-343 could explain its lower toxicity than RP-170 or etanidazole. The therapeutic risk index defined as D1.5/LD50 (D1.5 is the sensitizer dose to obtain the SER of 1.5 in vivo) for RP-343, RP-170 and etanidazole were 0.022, 0.033 and 0.036, respectively. Especially, the effectively lower therapeutic risk index for RP-343 presents the possibility of clinical advantage over etanidazole.


Assuntos
Neoplasias Experimentais/tratamento farmacológico , Nitroimidazóis/uso terapêutico , Nucleosídeos/uso terapêutico , Radiossensibilizantes/uso terapêutico , Animais , Hipóxia Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Cães , Relação Dose-Resposta a Droga , Etanidazol/administração & dosagem , Etanidazol/farmacocinética , Etanidazol/uso terapêutico , Feminino , Técnicas In Vitro , Injeções Intravenosas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/radioterapia , Nitroimidazóis/administração & dosagem , Nitroimidazóis/farmacocinética , Nucleosídeos/administração & dosagem , Nucleosídeos/farmacocinética , Radiossensibilizantes/administração & dosagem
14.
Br J Pharmacol ; 128(1): 241-7, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10498858

RESUMO

1. The aim of the present study was to characterize the subtypes of bradykinin (BK) receptors that evoke the relaxation and contraction induced by BK and to identify the main contracting and relaxing factors in isolated porcine basilar artery by measuring changes in isometric tension and a thromboxane (TX) metabolite. 2. Endothelial denudation completely abolished both responses. [Thi5,8, D-Phe7]-BK (a B2-receptor antagonist) inhibited the BK-induced relaxation and contraction, whereas des-Arg9, [Leu8]-BK (a B1-receptor antagonist) had no effect. 3. L-nitro-arginine (L-NA, a nitric oxide synthase inhibitor) completely inhibited BK-induced relaxation. Indomethacin (a cyclo-oxygenase inhibitor) completely and ONO-3708 (a TXA2/prostaglandin H2 receptor antagonist) partially inhibited BK-induced contraction, whereas OKY-046 (a TXA2 synthase inhibitor) and nordihydroguaiaretic acid (a lipoxygenase inhibitor) did not. 4. In the presence of L-NA, the contractile response to BK was inhibited by indomethacin or ONO-3708 and was competitively antagonized by [Thi5,8, D-Phe7]-BK (pA2=7.50). In the presence of indomethacin, the relaxant response to BK was inhibited by L-NA and was competitively antagonized by [Thi5,8, D-Phe7]-BK (pA2=7.59). 5. TXA2 release was not induced by BK-stimulation. 6. These results suggest that the endothelium-dependent relaxation and contraction to BK in the porcine basilar artery is mediated via activation of endothelial B2-receptors. The main relaxing factor may be NO and the main contracting factor may be prostaglandin H2.


Assuntos
Artéria Basilar/fisiologia , Endotélio Vascular/metabolismo , Receptores da Bradicinina/metabolismo , Vasoconstrição , Vasodilatação , Animais , Artéria Basilar/citologia , Artéria Basilar/efeitos dos fármacos , Artéria Basilar/metabolismo , Bosentana , Bradicinina/análogos & derivados , Bradicinina/antagonistas & inibidores , Bradicinina/farmacologia , Antagonistas dos Receptores da Bradicinina , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Feminino , Técnicas In Vitro , Indometacina/farmacologia , Masculino , Masoprocol/farmacologia , Metacrilatos/farmacologia , Nitroarginina/farmacologia , Papaverina/farmacologia , Receptor B1 da Bradicinina , Receptor B2 da Bradicinina , Receptores da Bradicinina/agonistas , Sulfonamidas/farmacologia , Suínos , Tromboxano A2/análogos & derivados , Tromboxano A2/farmacologia , Tromboxanos/metabolismo , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
15.
J Heart Lung Transplant ; 19(12): 1193-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11124489

RESUMO

BACKGROUND: The mechanisms of intimal thickening in cardiac allograft vasculopathy (CAV) remain controversial after heart transplantation. Matrix metalloproteinase-2 (MMP-2) plays a crucial role in degrading extracellular matrix (ECM) during neointimal formation. Recently, it has been revealed that MMP-2 is activated by membrane-type 1 matrix metalloproteinase (MT1-MMP). This process involves tissue inhibitor of MMP-2 (TIMP-2), forming an MT1-MMP/TIMP-2/pro-MMP-2 complex. In this study, we hypothesize that these components contribute to the pathogenesis of CAV. METHODS: Heterotopic cardiac allografting was performed in randomly paired Japanese monkeys with an immunosuppressive regimen of intravenous administration of antihuman CD18 monoclonal antibody. The donor hearts were harvested at Days 22, 28, 40, 41, and 95 posttransplantation. We examined expression of MMP-2, MT1-MMP, and TIMP-2 of graft vessels using immunohistochemistry and protein level by western blot analysis. RESULTS: Pathologically, various degrees of neointimal formation were observed. In the allografts harvested at Days 22, 28, 40, and 41, MT1-MMP was expressed in the endothelial cells and smooth muscle cells (SMCs) in media of some arteries without histological change, accompanied by expression of MMP-2 and TIMP-2. In the severely thickened neointima of the allograft harvested at Day 95, MMP-2 and faint MT1-MMP were expressed in SMCs of severely thickened neointima and media; TIMP-2 expression was seen only in noncollagenous tissue of severely thickened neointima. MMP-2 protein was more intensely expressed in the allograft harvested at Day 95 than in the allograft harvest at Day 41, while TIMP-2 protein level was almost same in the 2 samples. CONCLUSION: We observed the simultaneous expression of MMP-2, MT1-MMP, and TIMP-2. Thus, ECM degradation triggered by MT1-MMP/TIMP-2/pro-MMP-2 complex could be a novel mechanism of CAV.


Assuntos
Vasos Coronários/enzimologia , Transplante de Coração/fisiologia , Metaloendopeptidases/genética , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Western Blotting , Antígenos CD18/imunologia , Doença das Coronárias/enzimologia , Doença das Coronárias/etiologia , Vasos Coronários/patologia , Endotélio Vascular/enzimologia , Endotélio Vascular/patologia , Ativação Enzimática , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Seguimentos , Regulação Enzimológica da Expressão Gênica , Transplante de Coração/patologia , Humanos , Hiperplasia , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Injeções Intravenosas , Macaca , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/metabolismo , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/patologia , Distribuição Aleatória , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Transplante Heterotópico , Transplante Homólogo , Túnica Íntima/enzimologia , Túnica Íntima/patologia , Túnica Média/enzimologia , Túnica Média/patologia
17.
Cancer Genet Cytogenet ; 36(1): 103-7, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3203292

RESUMO

A patient with a variant form of acute promyelocytic leukemia (M3 variant) associated with an increased number of basophils was found to present a reciprocal translocation, t(9;14)(q34;q22) in addition to t(15;17)(q22;q12). Although several cases of acute nonlymphocytic leukemia with increased bone marrow and peripheral blood basophils have been reported, this is the first case in which both the t(9;14) and basophilia were observed in a patient with M3. Our findings support the hypothesis that 9q34 may be associated with the chromosomal location of genes regulating the production and maturation of basophils.


Assuntos
Basófilos/patologia , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 15 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 9 , Leucemia Promielocítica Aguda/genética , Translocação Genética , Adulto , Humanos , Cariotipagem , Leucemia Promielocítica Aguda/patologia , Contagem de Leucócitos , Masculino
18.
Cancer Genet Cytogenet ; 49(1): 69-74, 1990 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-2397475

RESUMO

Cytogenetic study was performed on a patient with T-cell acute lymphoblastic leukemia (T-ALL). It revealed a chromosomal translocation between chromosome bands 8q24 and 14q11. 8q24 is known to encode the oncogene c-myc, while 14q11 encodes the genes for T-cell receptor-alpha (TCR-alpha) and T-cell receptor-delta (TCR-delta). Therefore, this chromosomal translocation t(8;14) (q24;q11) seemed to be unique and specific to T-cell malignancy.


Assuntos
Cromossomos Humanos Par 14 , Cromossomos Humanos Par 8 , Leucemia-Linfoma de Células T do Adulto/genética , Translocação Genética , Adulto , Bandeamento Cromossômico , Sondas de DNA , Marcadores Genéticos , Humanos , Cariotipagem , Masculino , Hibridização de Ácido Nucleico , Proto-Oncogenes , Receptores de Antígenos de Linfócitos T/genética
19.
Cancer Genet Cytogenet ; 20(1-2): 121-7, 1986 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-3455854

RESUMO

A patient with chronic myelogenous leukemia (CML) associated with a remarkable increase of micromegakaryocytes in bone marrow was revealed to have an abnormality of a long arm of chromosome #3, i.e., inv(3)(q21q26), in addition to a complex Ph translocation: t(9;22;15)(q34;q11;q22). Although several cases of acute leukemia with inv(3)(q21q26) and abnormal megakaryocytes have been reported, this is the first case in which the association of inv(3)(q21q26) with a megakaryocytic abnormality was observed in a patient with CML. Our findings suggest that this structural rearrangement may be more specifically associated with abnormal thrombopoiesis than are other structural anomalies of 3q.


Assuntos
Plaquetas , Inversão Cromossômica , Cromossomos Humanos 1-3 , Hematopoese , Leucemia Mieloide/genética , Humanos , Leucemia Mieloide/sangue , Masculino , Megacariócitos/patologia , Pessoa de Meia-Idade , Cromossomo Filadélfia , Contagem de Plaquetas
20.
BioDrugs ; 12(3): 159-73, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18031174

RESUMO

Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease that predominantly occurs in middle-aged women. It is characterised by inflammatory destruction of interlobular and septal bile ducts, subsequent fibrosis, and finally liver cirrhosis. The disease slowly progresses over decades and may lead to liver failure. It is more frequently diagnosed now than it was in the past probably because of a greater awareness of the disease. Liver function tests reveal an elevation of serum alkaline phosphatase and micro-glutamyltransferase levels with or without elevated aminotransferase levels. Antimitochondrial antibodies (AMAs) are found in 95% of patients with PBC. AMAs have been shown to be directed against the 2-oxo-acid dehydrogenase complexes located on the inner membrane of the mitochondria. However, AMA titres do not correlate with disease severity or progression, and the role of AMAs in the pathogenesis of primary biliary cirrhosis is not yet known. The disease is frequently associated with other autoimmune disease, including Sjogren's syndrome, thyroid disorders and scleroderma. Most therapeutic efforts have been directed at altering the immune response. Ursodeoxycholic acid (UDCA) appears to be effective therapy in preventing or delaying the need for liver transplantation and improving survival. However, a number of patients receiving UDCA still develop progressive disease and go on to transplantation, which is an effective therapy at the end stage of the disease. Various prognostic models have been proposed to assist in the determination of the optimum timing of liver transplantation.

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