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1.
Br J Dermatol ; 164(6): 1348-55, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21410660

RESUMO

BACKGROUND: Because inflammatory cytokines are known to be potent inducers of matrix metalloproteinases (MMPs), and MMPs themselves can promote inflammation, we speculated that MMP activation might be involved in the pathogenesis of Henoch-Schönlein purpura (HSP) vasculitis. OBJECTIVES: To investigate the gene expression profile of all known MMPs and tissue inhibitors of metalloproteinases (TIMPs) in children with HSP and to examine the role, if any, of MMPs in the pathogenesis of HSP. METHODS: Peripheral blood samples were obtained from 10 patients with HSP (nine were in the acute stage, one had HSP nephritis) and four healthy controls. Peripheral blood samples were also taken from the nine patients with HSP when they reached the convalescent stage of the disease. From these samples, total RNA was purified and gene expressions were measured using real-time polymerase chain reaction. RESULTS: MMP-8 expression was decreased in patients with arthralgia (P = 0·038), and MMP-3 (P = 0·03) and TIMP-4 expressions (P = 0·016) were elevated in HSP patients with nephritis. Soft tissue oedema was associated with decreased expressions of MMP-26 (P = 0·038) and MMP-28 (P = 0·038). MMP-1, MMP-8, MMP-9, MMP-10, MMP-13, MMP-16 and MMP-26 levels were significantly higher in patients in the acute stage of HSP than in normal controls (P < 0·05). MMP-9 (P = 0·097) and MMP-19 (P = 0·054) levels decreased to borderline significance in patients in the convalescent stage compared with those in the acute stage. The duration of steroid administration was negatively correlated with MMP-1, MMP-2, MMP-7, MMP-10, MMP-12, MMP-19, MMP-23 and TIMP-1 levels (P < 0·05), suggesting a suppressive effect of steroids on the expressions of MMPs and TIMPs. CONCLUSIONS: This is the first study to describe the expression profile of all known MMPs and TIMPs in children with HSP, and our results suggested that abnormal levels of MMP and TIMP activity may have a role in the pathogenesis of HSP.


Assuntos
Vasculite por IgA/genética , Metaloproteinases da Matriz/genética , Inibidores Teciduais de Metaloproteinases/genética , Dor Abdominal/genética , Doença Aguda , Artralgia/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , DNA Complementar/metabolismo , Edema/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Masculino , Metaloproteinases da Matriz/metabolismo , Nefrite/genética , Reação em Cadeia da Polimerase em Tempo Real , Inibidores Teciduais de Metaloproteinases/metabolismo
2.
Oncogene ; 20(1): 16-23, 2001 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-11244501

RESUMO

The hepatitis B virus HBx protein is a promiscuous transactivator implicated in the development of hepatocellular carcinoma. The ectopic expression of HBx fails to transform both primary and immortalized rodent cells, but rather induces apoptosis. Furthermore, most transgenic mice harboring HBx do not develop liver tumors. Thus, it remains unclear whether and how HBx contributes to oncogenesis. Here, we show that HBx collaborates with activated H-ras to transform immortalized rodent cells. Indeed, REF52 cells transfected by both HBx and activated H-ras were morphologically transformed and were able to grow in soft agar. Remarkably, nude mice injected with REF52 cells transfected by both HBx and activated H-ras developed tumors, whereas the mice injected with REF52 cells transfected by either gene alone did not. Thus, we concluded that HBx could contribute to neoplastic transformation of cells in collaboration with other oncogenes, such as H-ras, that renders cells to overcome the HBx-mediated apoptosis. Further, we found that HBx mediated apoptosis was suppressed by activated H-ras through activation of the phosphatidylinositol-3 kinase and Akt pathway. Data presented here firmly established the oncogenic potential of HBx during multistage carcinogenesis. Oncogene (2001) 20, 16 - 23.


Assuntos
Apoptose/genética , Transformação Celular Neoplásica/genética , Transformação Celular Viral/genética , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Genes ras , Vírus da Hepatite B/genética , Proteínas Serina-Treonina Quinases , Transativadores/genética , Células 3T3 , Animais , Linhagem Celular , Linhagem Celular Transformada , Embrião de Mamíferos , Genes Supressores , Genes Virais , Camundongos , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Tirosina Quinases/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-akt , Ratos , Transdução de Sinais/genética , Transfecção , Proteínas Virais Reguladoras e Acessórias , Proteínas Estruturais Virais/genética
4.
Br J Radiol ; 78(929): 447-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15845942

RESUMO

Pericardial rupture following blunt chest trauma is rare, and is not usually diagnosed pre-operatively. If pericardial rupture is not recognized and treated promptly, it may be fatal owing to cardiac herniation. We report a case of traumatic herniation of the heart for which a CT scan and MRI made a major contribution to the diagnosis.


Assuntos
Traumatismos Cardíacos/diagnóstico , Ruptura Cardíaca/diagnóstico , Pericárdio/lesões , Ferimentos não Penetrantes/etiologia , Acidentes de Trânsito , Traumatismos Cardíacos/etiologia , Ruptura Cardíaca/etiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos
5.
J Bone Joint Surg Br ; 87(7): 979-83, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15972915

RESUMO

We reviewed three infants with destructive osteomyelitis involving the proximal tibial epiphysis at a follow-up of eight to 22 years. All cases showed early radiographic destructive changes in the medial or lateral aspects of the epiphysis and metaphysis. Despite the ominous early appearance of the epiphysis, all cases showed spontaneous re-ossification of the epiphysis with restoration of the tibial condyle and preservation of joint congruity. The patients, however, developed a valgus or varus deformity which was treated satisfactorily with one to three proximal tibial osteotomies. The potential for regeneration of the epiphysis following infantile osteomyelitis of the proximal tibia suggests these cases should be treated expectantly with regard to joint congruity.


Assuntos
Regeneração Óssea/fisiologia , Osteomielite/fisiopatologia , Tíbia/fisiologia , Humanos , Recém-Nascido , Deformidades Articulares Adquiridas/etiologia , Deformidades Articulares Adquiridas/fisiopatologia , Deformidades Articulares Adquiridas/cirurgia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/fisiopatologia , Osteomielite/diagnóstico por imagem , Osteotomia/métodos , Radiografia , Reoperação , Tíbia/diagnóstico por imagem , Resultado do Tratamento
6.
Exp Hematol ; 27(9): 1428-39, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10480434

RESUMO

The functional significance of CD95/Fas expressed by candidate hematopoietic stem cells (HSCs) from human fetal liver was studied by testing the effect of agonistic anti-CD95 monoclonal antibody (mAb) CH-11 and soluble CD95 ligand (sCD95L) on the growth of CD34(++)CD38(-)lineage cells in vitro. Candidate fetal HSCs exhibited a dose-dependent proliferative response to CH-11 as well as to sCD95L when combined with kit ligand (KL) + interleukin 3 (IL-3) under serum-deprived culture conditions. CH-11 mAb increased, in a synergistic fashion, the number of myeloid colony-forming unit culture (CFU-C) generated by candidate HSCs in liquid cultures with the cytokine combinations KL + IL-3, KL + granulocytemacrophage colony-stimulating factor, and KL + IL-6. CH-11 mAb and sCD95L also enhanced erythropoiesis supported by KL + IL-3 + erythropoietin (Epo). Furthermore, sCD95L was able to increase the number of megakaryocytes, granulocytes, and CD34- cells generated in the presence of KL + IL-3 + Epo + thrombopoietin. An analysis performed using Western blotting revealed that the membrane-bound CD95L (mCD95L) was expressed by both immature (total CD34+/++) and mature (CD34-) hematopoietic lin(-) FL cells. Among the CD34(++)lin(-)cells, both the freshly isolated CD38+ and CD38 subsets as well as CD95+ and CD95- cells constitutively expressed mCD95L, demonstrating that the CD95/CD95L system represents a paracrine and potentially autocrine regulator of early hematopoiesis. To study the role of the endogenously produced CD95L, we determined the effects of a neutralizing anti-CD95L NOK-1 on the growth of candidate HSCs. By blocking the endogenous CD95L with NOK-1 mAb, we observed an increase in CFU-C generated by candidate HSCs. We conclude that the endogenous CD95L has an inhibitory effect on fetal candidate HSCs, which can be blocked by sCD95L and CH-11 mAb.


Assuntos
Antígenos CD , Hematopoese Extramedular/fisiologia , Células-Tronco Hematopoéticas/citologia , Sistema Hematopoético/embriologia , Fígado/citologia , Glicoproteínas de Membrana/fisiologia , Receptor fas/fisiologia , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Adulto , Anticorpos Monoclonais/farmacologia , Antígenos CD34/análise , Antígenos de Diferenciação/análise , Células Sanguíneas/citologia , Células da Medula Óssea/citologia , Linhagem da Célula , Relação Dose-Resposta Imunológica , Sinergismo Farmacológico , Proteína Ligante Fas , Sangue Fetal/citologia , Hematopoese Extramedular/efeitos dos fármacos , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Sistema Hematopoético/citologia , Sistema Hematopoético/crescimento & desenvolvimento , Humanos , Recém-Nascido , Fígado/embriologia , NAD+ Nucleosidase/análise , Especificidade de Órgãos , Proteínas Recombinantes de Fusão/farmacologia
7.
Bone Joint J ; 97-B(6): 824-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26033064

RESUMO

The purpose of this study was to evaluate the expression of acid-sensing ion channels (ASICs) in the capsule and synovial fluid of patients with frozen shoulder. Capsular tissue and synovial fluid were obtained from 18 patients with idiopathic frozen shoulder (FS group) and 18 patients with instability of the shoulder (control group). The expressions of ASIC1, ASIC2, and ASIC3 in the capsule were determined using the reverse transcriptase-polymerase chain reaction, immunoblot analysis, and immunohistochemistry (IHC). The concentrations in synovial fluid were evaluated using an enzyme-linked immunosorbent assay. The mRNA expression of ASIC1, ASIC2 and ASIC3 in the capsule were significantly increased in the FS group compared with the control group. The protein levels of these three ASICs were also increased. The increased expressions were confirmed by IHC. Of the ASICs, ASIC3 showed the greatest increase in both mRNA and levels of expression compared with the control group. The levels of ASIC1 and ASIC3 in synovial fluid were significantly increased in the FS group. This study suggests that ASICs may play a role as mediators of inflammatory pain and be involved in the pathogenesis of frozen shoulder.


Assuntos
Canais Iônicos Sensíveis a Ácido/metabolismo , Bursite/metabolismo , Cápsula Articular/metabolismo , Regulação para Cima/fisiologia , Canais Iônicos Sensíveis a Ácido/biossíntese , Bursite/fisiopatologia , Humanos , Imuno-Histoquímica , RNA Mensageiro/metabolismo , Líquido Sinovial/metabolismo
8.
Eur J Cancer ; 39(2): 184-91, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12509950

RESUMO

The activation of coagulation, angiogenesis and inflammatory cytokines are considered to be related with tumour growth and metastasis. We investigated the plasma levels of platelet microparticles (PMP), vascular endothelial growth factor (VEGF), IL-6, and the chemokine RANTES in patients with gastric cancer (n=109) and in healthy controls (n=29). The plasma levels of PMP, IL-6 and RANTES were significantly higher in the patients than in the healthy controls, and plasma levels of PMP, VEGF, IL-6 and RANTES were significantly higher in patients with stage IV disease than those in patients with stage I or stage II/III. In terms of predicting distant metastasis, the sensitivities of PMP, VEGF, IL-6 and RANTES were 93.3%, 56.7%, 70.0% and 81.8%, respectively, and the corresponding specificities were 91.1%, 64.6%, 79.7% and 50.0%. Among these parameters, PMP had the highest diagnostic accuracy. Significant correlations were found between PMP, VEGF, IL-6 and RANTES. This study demonstrates that the plasma levels of PMP, VEGF, IL-6 and RANTES were markedly increased in patients with stage IV disease, and that these increased plasma levels of IL-6, RANTES, and especially PMP, might be useful for identifying metastatic gastric patients.


Assuntos
Biomarcadores Tumorais/sangue , Plaquetas , Quimiocina CCL5/sangue , Fatores de Crescimento Endotelial/sangue , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Interleucina-6/sangue , Linfocinas/sangue , Neoplasias Gástricas/sangue , Neoplasias Gástricas/diagnóstico , Idoso , Coagulação Sanguínea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neovascularização Patológica , Ativação Plaquetária/fisiologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
9.
Atherosclerosis ; 154(2): 449-53, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11166778

RESUMO

Fibronectin is a paradigm adhesive protein which has been implicated in the regulation of several cellular processes and cell-cell interactions. Large amounts of fibronectin have been detected in atherosclerotic plaques, while hypertension in animal models has been shown to rapidly increase fibronectin expression in arterial walls. The aim of the present study was to determine the levels of plasma fibronectin (FN) in 133 patients with ischemic heart disease and in 36 normal controls, and to investigate the possible association with blood pressure. Plasma FN levels in patients with ischemic heart disease were found to be significantly elevated (mean+/-S.D.; 46.5+/-14.2 mg/dl) compared with the control group (38.0+/-14.2 mg/dl) (P=0.002). Plasma FN concentrations were significantly different between the hypertensive group (52.9+/-14.5 mg/dl) and the normal blood pressure group (41.4+/-11.8 mg/dl) among the patients with ischemic heart disease (P<0.001). Plasma FN concentration was positively correlated with total cholesterol, triglyceride, systolic blood pressure and body mass index. In conclusion, the plasma fibronectin level may have pathogenetic implications in association with lipid components and blood pressure in patients with ischemic heart disease.


Assuntos
Fibronectinas/sangue , Isquemia Miocárdica/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Pressão Sanguínea , Colesterol/sangue , Angiografia Coronária , Progressão da Doença , Feminino , Humanos , Hipertensão/sangue , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/fisiopatologia , Razão de Chances , Fatores de Risco , Triglicerídeos/sangue
10.
Thromb Haemost ; 74(3): 864-7, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8571313

RESUMO

We determined the plasma antigen levels of urokinase-type plasminogen activator(u-PA) and plasminogen activator inhibitor 2(PAI-2) in 41 patients with hepatocellular carcinoma and 28 patients with different stages of liver cirrhosis. No significant differences of u-PA and PAI-2 levels were calculated between the two groups of tumor patients (HCC) and liver cirrhosis without tumor (non-HCC). Within both study groups, no significant differences were found in u-PA and PAI-2 levels of the different Child categories. Discriminative functions of both u-PA and PAI-2 (total error count estimates of 43.1% and 43.6%, respectively), were low compared to that (29.0%) of alpha-fetoprotein (AFP). The combinations of AFP and u-PA lowered the total error rate (21.9%) more than that of each marker alone. However, whether plasma u-PA and PAI-2 may be considered as a risk factor further investigation was needed and our findings raise the question as to whether these markers could be considered as useful screening markers for earlier detection of HCC in liver cirrhosis because discriminant functions of u-PA and PAI-2 were not significant. Sensitivities and specificities of u-PA and PAI-2 were also not high enough, resulting in the ranges of total diagnostic efficiency from 43% to 50%, and, from 49% to 63%, respectively, at different cut-off values. No direct relationship was detected between AFP and u-PA, between AFP and PAI-2, and between u-PA and PAI-2.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/diagnóstico , Cirrose Hepática/diagnóstico , Neoplasias Hepáticas/diagnóstico , Ativador de Plasminogênio Tipo Uroquinase/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Inibidor 2 de Ativador de Plasminogênio/sangue , Valor Preditivo dos Testes
11.
Invest Radiol ; 27(10): 785-9, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1399433

RESUMO

RATIONALE AND OBJECTIVES: The authors assessed the influence of a prior reader's opinion on the detectability of rib fractures. METHODS: Six pairs of observers read the chest PA radiographs of 92 subjects with rib fracture(s) and 28 normal subjects to detect rib fracture(s) according to a five-point rating of confidence with three methods. In method A, each reader read films as a primary reader. In method B, each reader read films after knowing his or her partner's opinion. In method C, each reader initially observed films and then made the final decision after knowing his or her partner's opinion. RESULTS: Methods B and C were superior to method A in sensitivity. There was no difference in performance between methods B and C. Method C required a significantly longer time than the other methods. CONCLUSION: Detection of rib fractures is improved by seeking the opinion of other observers.


Assuntos
Fraturas Ósseas/diagnóstico por imagem , Costelas/diagnóstico por imagem , Costelas/lesões , Humanos , Curva ROC , Radiografia , Sensibilidade e Especificidade
12.
Exp Mol Med ; 31(1): 47-51, 1999 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-10231023

RESUMO

A heterozygous GTG to ATG (Val297Met) mutation was detected in a patient with inherited protein C deficiency and deep vein thrombosis. Cosegregation of the mutation with protein C deficiency was observed through a family pedigree study. Molecular models of the serine protease domains of wild type and mutant protein C were constructed by standard comparative method. Val 297 was found to be located in the hydrophobic core of the protein. Although the substitution of Met for Val does not greatly alter the hydrophobicity of the protein, it introduces a bulkier side chain, which yields steric hindrance between this residue and adjacent residues, such as Met364, Tyr393, Ile321, Ile323, and Val378. It seems that the Met can not fit into the tight packing into which it is trapped, thereby probably inducing misfolding and/or greater instability of the protein. Such misfolding and/or instability thereby eventually disturbs the catalytic triad, in consistent with the observed type I deficiency state.


Assuntos
Modelos Moleculares , Mutação Puntual , Deficiência de Proteína C/genética , Proteína C/química , Proteína C/genética , Serina Endopeptidases/química , Adulto , Sequência de Bases , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Reação em Cadeia da Polimerase/métodos , Conformação Proteica , Serina Endopeptidases/genética , Trombose Venosa/genética
13.
Exp Mol Med ; 33(2): 106-9, 2001 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-11460881

RESUMO

Hyperhomocysteinemia is known to be associated with an increased risk of myocardial infarction, stroke, peripheral arterial disease, and venous thrombosis. Gene polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MS) may account for reduced enzyme activity and hyperhomocysteinemia. A recent study has documented evidence of polygenic regulation of plasma homocyteine. We report here on a case of occlusive stroke at young age and hyperhomocysteinemia with homozygous VN (677C to T) variant in the MTHFR gene as well as homozygous D/D (2756G to A) variant in the MS gene.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Homozigoto , Hiper-Homocisteinemia/genética , Acidente Vascular Cerebral/genética , Tetra-Hidrofolatos/genética , Adulto , DNA/metabolismo , Enzimas de Restrição do DNA/metabolismo , Saúde da Família , Feminino , Variação Genética , Genótipo , Homocisteína/sangue , Homocisteína/genética , Humanos , Masculino , Polimorfismo Genético
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.
Phytochemistry ; 41(1): 213-6, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8588866

RESUMO

Three new dihydroflavonols, gericudranins A-C were isolated from the stem bark of Cudrania tricuspidata. They were identified as 6,8-di-p-hydroxybenzyltaxifolin, 8-p-hydroxybenzyltaxifolin and 6-p-hydroxybenzyltaxifolin, respectively, by means of spectral studies. These compounds were cytotoxic to human tumor cell lines, such as CRL 1579 (skin), LOX-IMVI (skin), MOLT-4F (leukemia), KM12 (colon) and UO-31 (renal) in culture, with ED50 values of 2.7-31.3 micrograms ml-1.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Plantas Medicinais , Quercetina/análogos & derivados , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo , Humanos , Neoplasias Renais , Leucemia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais , Caules de Planta , Quercetina/química , Quercetina/isolamento & purificação , Quercetina/toxicidade , Neoplasias Cutâneas , Árvores , Células Tumorais Cultivadas
16.
J Gastroenterol ; 32(6): 734-9, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9430010

RESUMO

We simultaneously recorded gastric emptying of radio-opaque markers (ROMs) and monitored serial changes in plasma acetaminophen (AAP) levels to demonstrate the relationship between the ROM and the AAP methods, and we investigated the effect of a single intravenous dose of erythromycin (EM) on gastric emptying in healthy human subjects. After an overnight fast, subjects were randomized to receive either placebo or EM lactobionate (Abbott, North Chicago, IL, USA) 250 mg intravenously in a single dose, given immediately before a standard meal. Subjects ingested 1.5 g of AAP and ROMs with the test meal. A supine plain abdominal radiograph was taken 1, 2, 3, and 6 h after ingestion of the test meal. Peripheral blood samples were obtained 0, 0.5, 1, 1.5, 2, 3, and 6 h after ingestion of the test meal. EM significantly accelerated gastric emptying of ROMs. By 6 h, no markers remained in the stomach in any of the subjects in the placebo or EM groups. By 120 min, half of the ROMs had passed into the duodenum in 12.5% of subjects after placebo, whereas EM injection resulted in gastric emptying of half of the ROMs in all subjects. There was no difference in plasma AAP concentration between the placebo and EM groups. There were significant correlations between maximum plasma AAP concentration and gastric emptying of ROMs 120 min after ingestion (r = 0.546; P = 0.019), and between time of maximum plasma AAP concentration and gastric emptying of ROMs 120 min after ingestion (r = -0.568; P = 0.014). The time taken to reach the peak concentrations ranged from 30 to 90 min after ingestion, whereas most ROMs were emptied 120 min after ingestion. We conclude that the gastric emptying assessed by ROMs and by serial changes in plasma AAP level are good, non-invasive, clinically applicable tests, with a significant correlation between the two tests. A single intravenous dose of EM had a prokinetic effect on gastric emptying, assessed by ROMs, in healthy human subjects.


Assuntos
Acetaminofen/farmacocinética , Eritromicina/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Adulto , Meios de Contraste , Humanos , Masculino
17.
Clin Chim Acta ; 314(1-2): 113-23, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11718686

RESUMO

BACKGROUND: In addition to apolipoprotein(a) [apo(a)] kringle 4 variable number of tandem repeat (K4-VNTR), pentanucleotide repeat polymorphism (PNRP) and C/T(+93) polymorphism [C/T(+93)] of apo(a) gene have been suggested to be related to lipoprotein(a) [Lp(a)] concentration. We studied the distribution of these genetic polymorphisms and their relationship with Lp(a) concentrations in a Korean population. METHODS: One hundred thirty-two Korean adults were examined. Lp(a) was measured with enzyme-linked immunosorbent assay (ELISA). Apo(a) K4-VNTR was measured by high-resolution SDS-agarose gel separation and ECL Western blotting method. PNRP was measured after DNA amplification. The C/T(+93) ratio was measured by a amplification refractory mutation system. RESULTS: Lp(a) was inversely correlated with K4-VNTR (r=0.732, p<0.0001), but was associated neither with any PNRP haplotype nor with C/T(+93) by multiple regression analysis, although we found a significant decrease of Lp(a) in PNRP 9/9 individuals (p<0.01). There was a strong linkage disequilibrium between 9 haplotypes of PNRP and the T haplotype of C/T(+93). CONCLUSIONS: Inverse relationship between serum Lp(a) and K4 number of apo(a) was confirmed in normal Korean adults. PNRP 9/9 genotype appeared to have a reducing effect on Lp(a), but neither 9 haplotype heterozygotes of PNRP nor the T haplotype C/T(+93) affected Lp(a) concentrations in Koreans.


Assuntos
Apolipoproteínas A/genética , Lipoproteína(a)/genética , Polimorfismo Genético/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Humanos , Coreia (Geográfico) , Masculino , Pessoa de Meia-Idade , Análise de Regressão
18.
IEEE Trans Med Imaging ; 16(5): 495-502, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9368105

RESUMO

This paper proposes an adaptive image enhancement method for mammographic images, which is based on the first derivative and the local statistics. The adaptive enhancement method consists of three processing steps. The first step is to remove the film artifacts which may be misread as microcalcifications. The second step is to compute the gradient images by using the first derivative operators. The third step is to enhance the important features of the mammographic image by adding the adaptively weighted gradient images. Local statistics of the image are utilized for adaptive realization of the enhancement, so that image details can be enhanced and image noises can be suppressed. The objective performances of the proposed method were compared with those by the conventional image enhancement methods for a simulated image and the seven mammographic images containing real microcalcifications. The performance of the proposed method was also evaluated by means of the receiver operating-characteristics (ROC) analysis for 78 real mammographic images with and without microcalcifications.


Assuntos
Mamografia/métodos , Intensificação de Imagem Radiográfica/métodos , Algoritmos , Artefatos , Doenças Mamárias/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Simulação por Computador , Feminino , Humanos , Mamografia/estatística & dados numéricos , Modelos Biológicos , Curva ROC
19.
Toxicol Lett ; 116(1-2): 103-11, 2000 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-10906427

RESUMO

In order to investigate occupational diseases related to welding fume exposure, such as nasal septum perforation, pneumoconiosis and manganese intoxication, we built a welding fume exposure system that included a welding fume generator, exposure chamber and fume collector. The fume concentrations in the exposure chamber were monitored every 15 min during a 2-h exposure. Fume (mg/m(3)) concentrations of major metals, including Fe, Mn, Cr, and Ni were found to be consistently maintained. An acute inhalation toxicity study was conducted by exposing male Sprague-Dawley rats to the welding fumes generated in this apparatus by stainless steel arc welding. The rats were exposed in the inhalation chamber to a welding fume with a concentration of 62 mg/m(3) total suspended particulates for 4 h. Animals were sacrificed at 4 h and at 1, 3, 7, 10, and 14 days after exposure. Histopathological examinations were conducted on the animals' upper respiratory tracts, including the nasal pathway and the conducting airway, and on the gas exchange region including the alveolar ducts, alveolar sacs, and alveoli. Diameters of fume particles varied from 0.02 to 0.81 microm and were distributed log normally, with a mean diameter of 0.1 microm and geometric standard deviation of 1.42. Rats exposed to the welding fume for 4 h did not show any significant respiratory system toxicity. The mean particle diameter of 0.1 microm resulted in little adsorption of the welding fume particles in the upper respiratory tract. Particle adsorption took place principally in the lower respiratory tracts, including bronchioles, alveolar ducts, alveolar sacs, and alveoli.


Assuntos
Exposição Ocupacional/efeitos adversos , Sistema Respiratório/patologia , Aço Inoxidável , Soldagem , Administração por Inalação , Animais , Cromo/toxicidade , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Sistema Respiratório/metabolismo
20.
Blood Coagul Fibrinolysis ; 13(5): 393-7, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12138366

RESUMO

Platelet microparticles (PMP) are submicroscopic membrane vesicles released by platelets during activation. Flow cytometry is the most widely used method for quantifying PMP, but the optimization of the technical method has not yet been fully evaluated. This study was designed to assess the pre-analytical variables including blood sampling conditions, and to evaluate the analytical variations including effect of the platelet-specific antibodies and quantitative beads, precision, linearity and accuracy in comparison with beta-thromboglobulin, which is one of the platelet activation markers. Numbers of PMP collected into citrate-theophylline-adenosine-dipyridamole (CTAD) tubes were increased with time, but to a lesser extent than when collected into sodium citrate tubes. The precision of the PMP assay was relatively high. Excellent linear correlation was observed for dilution linearity. Regarding the platelet-specific antibodies used, anti-CD41a-labeled samples resulted in higher PMP levels than those labeled with anti-CD61 and anti-CD42a. There was no significant difference of PMP counts according to the quantitative beads. The PMP assay is well correlated with beta-thromboglobulin levels. Our findings suggest that blood samples for the PMP assay should be collected in a CTAD tube and delayed measurement is not allowed to avoid artefactual platelet activation. The PMP assay can be used successfully as a useful marker of the detection of in vivo platelet activation, provided that pre-analytical and technical points are optimally taken into consideration.


Assuntos
Plaquetas/ultraestrutura , Citometria de Fluxo/métodos , Ativação Plaquetária , Adenosina/farmacologia , Adulto , Anticoagulantes/farmacologia , Biomarcadores , Preservação de Sangue , Coleta de Amostras Sanguíneas/métodos , Citratos/farmacologia , Dipiridamol/farmacologia , Humanos , Microesferas , Tamanho da Partícula , Ativação Plaquetária/efeitos dos fármacos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Citrato de Sódio , Soluções , Teofilina/farmacologia , beta-Tromboglobulina/análise
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