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1.
Br J Surg ; 103(13): 1795-1803, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27682642

RESUMO

BACKGROUND: Previous RCTs have failed to demonstrate the usefulness of combining energy devices with the conventional clamp crushing method to reduce blood loss during liver transection. Here, the combination of an ultrasonically activated device (UAD) and a bipolar vessel-sealing device (BVSD) with crush clamping was investigated. METHODS: Patients scheduled to undergo hepatectomy at the University of Tokyo Hospital or Nihon University Itabashi Hospital were eligible for this parallel-group, single-blinded randomized study. Patients were assigned to a control group (no energy device used), an UAD group or a BVSD group. The primary endpoint was the volume of blood loss during liver transection. Outcomes of the control group and the combined energy device groups (UAD plus BVSD) were first compared. Pairwise comparisons among the three groups were made for outcomes for which the combined energy device group was superior to the control group. RESULTS: A total of 380 patients were enrolled between July 2012 and May 2014; 116 patients in the control group, 122 in the UAD group and 123 in the BVSD group were included in the final analysis. Median blood loss during liver transection was lower in the combined energy device group (245 patients) than in the control group (116 patients): median 190 (range 0-3575) versus 230 (range 3-1570) ml (P = 0·048). Pairwise comparison revealed that blood loss was lower in the BVSD group than in the control group (P = 0·043). CONCLUSION: The use of energy devices combined with crush clamping reduced blood loss during liver transection. Registration number: C000008372 (www.umin.ac.jp/ctr/index.htm).


Assuntos
Hemostasia Cirúrgica/instrumentação , Hepatectomia/instrumentação , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica/prevenção & controle , Constrição , Feminino , Hemostasia Cirúrgica/métodos , Hepatectomia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Instrumentos Cirúrgicos , Resultado do Tratamento
2.
J Oral Rehabil ; 43(9): 678-82, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27328011

RESUMO

Several dynamic magnetic resonance imaging (MRI) techniques to observe swallowing and their parameters have been reported. Although these studies used several contrast enhancement liquids, no studies were conducted to investigate the most suitable liquids. The purpose of this study was to identify the optimal contrast enhancement liquid for dynamic MRI of swallowing. MRI was performed using a new sequence consisting of true fast imaging with steady-state precession, generalised auto-calibrating partially parallel acquisition and a keyhole imaging technique. Seven liquids were studied, including pure distilled water, distilled water with thickener at 10, 20 and 30 mg mL(-1) concentrations and oral MRI contrast medium at 1, 2 or 3 mg mL(-1) . Distilled water showed the highest signal intensity. There were statistically significant differences among the following contrast media: distilled water with thickener at 20 mg mL(-1) and the oral MRI contrast medium at 2 mg mL(-1) and 1 mg mL(-1) . It can be concluded that the optimal liquid for dynamic MRI of swallowing is a water-based substance that allows variations in viscosity.


Assuntos
Meios de Contraste/uso terapêutico , Transtornos de Deglutição/diagnóstico por imagem , Deglutição/fisiologia , Esôfago/diagnóstico por imagem , Aumento da Imagem , Imagem Cinética por Ressonância Magnética , Orofaringe/diagnóstico por imagem , Língua/fisiologia , Transtornos de Deglutição/fisiopatologia , Esôfago/fisiologia , Humanos , Aumento da Imagem/instrumentação , Aumento da Imagem/métodos , Imagem Cinética por Ressonância Magnética/métodos , Orofaringe/fisiologia , Viscosidade
4.
Neuroscience ; 279: 132-8, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25194790

RESUMO

Hearing loss related to aging is the most common sensory disorder among elderly individuals. Macrophage migration inhibitory factor (MIF) is a multi-functional molecule. The aim of this study was to identify the role of MIF in the inner ear. MIF-deficient mice (MIF(-/-) mice) of BALB/c background and wild-type BALB/c mice were used in this study. Expression of MIF protein in the inner ear was examined by immunohistochemistry in wild-type mice (WT). The hearing function was assessed by the click-evoked auditory brainstem response in both MIF(-/-) mice and WT at 1, 3, 6, 9, 12, and 18months of age. Morphological examination of the cochlea was also performed using scanning electron microscopy and light microscopy. MIF was observed in the spiral ligament, stria vascularis, Reissner's membrane, spiral ganglion cells (SGCs), saccular macula, and membranous labyrinth. The MIF(-/-) mice had a significant hearing loss as compared with the WT at 9, 12, and 18months of age. In the MIF(-/-) mice, scanning electron microscopy showed that the outer cochlear hair cells were affected, but that the inner cochlear hair cells were relatively well preserved. The number of SGCs was lower in the MIF(-/-) mice. MIF was strongly expressed in the mouse inner ear. Older MIF(-/-) mice showed accelerated age-related hearing loss and morphological inner ear abnormalities. These findings suggest that MIF plays an important role in the inner ear of mice.


Assuntos
Envelhecimento/fisiologia , Orelha Interna/fisiopatologia , Perda Auditiva/fisiopatologia , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Envelhecimento/patologia , Animais , Limiar Auditivo/fisiologia , Orelha Interna/patologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Perda Auditiva/patologia , Imuno-Histoquímica , Oxirredutases Intramoleculares/genética , Fatores Inibidores da Migração de Macrófagos/genética , Camundongos Endogâmicos BALB C , Camundongos Knockout , Microscopia Eletrônica de Varredura
6.
J Laryngol Otol ; 128(3): 255-62, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24621450

RESUMO

BACKGROUND: A close relationship between upper and lower respiratory tract diseases has been reported. However, little is known about pulmonary function in patients with upper respiratory tract diseases. METHODS: Pulmonary function was measured in: 68 patients with chronic rhinosinusitis without nasal polyps, 135 patients with chronic rhinosinusitis with nasal polyps, 89 patients with allergic rhinitis and 100 normal control subjects. The relationships between pulmonary function and clinical parameters were assessed. These parameters included radiographic severity of chronic rhinosinusitis, serum total immunoglobulin E levels, concentrations of cytokines in nasal secretions and exhaled nitric oxide levels. RESULTS: The pulmonary function of patients with chronic rhinosinusitis was significantly affected. The level of interleukin-5 in nasal secretions was significantly correlated with pulmonary function in patients with chronic rhinosinusitis. CONCLUSION: The findings indicated latent obstructive lung function changes in chronic rhinosinusitis patients. The cytokines in nasal secretions might be related to obstructive lung function changes in chronic rhinosinusitis.


Assuntos
Imunoglobulina E , Pulmão/fisiopatologia , Pólipos Nasais/fisiopatologia , Rinite/fisiopatologia , Sinusite/fisiopatologia , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Doença Crônica , Feminino , Humanos , Imunoglobulina E/sangue , Interleucina-5/imunologia , Pulmão/imunologia , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/metabolismo , Pólipos Nasais/sangue , Pólipos Nasais/diagnóstico por imagem , Pólipos Nasais/imunologia , Óxido Nítrico/metabolismo , Rinite/sangue , Rinite/diagnóstico por imagem , Rinite/imunologia , Rinite Alérgica/fisiopatologia , Índice de Gravidade de Doença , Sinusite/sangue , Sinusite/diagnóstico por imagem , Sinusite/imunologia , Espirometria , Tomografia Computadorizada por Raios X
8.
Br J Surg ; 99(11): 1584-90, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23027077

RESUMO

BACKGROUND: Abdominal drains have been placed prophylactically and removed in liver resection without robust evidence. The present study was designed to establish the optimal time for removal of such drains. METHODS: Data on abdominal prophylactic drains were analysed in a consecutive series of patients who underwent liver resection for malignancy between 2006 and 2009. Bilirubin levels in drain fluid were measured and bacteriological cultures were taken on days 1, 3, 5 and 7 after surgery. Drains were removed on day 3 if the drain-fluid bilirubin level was less than 5 mg/dl and bacteriological cultures were negative. Drains remained in situ until these conditions were met. RESULTS: A total of 514 abdominal drains were placed in 316 patients operated on in the study period. Fifty-eight patients (18·4 per cent) had positive drain-fluid cultures and 14 (4·4 per cent) had bile leakage (drain-fluid bilirubin level 5 mg/dl or more). Only one patient required ultrasound-guided abdominal drainage. On multivariable analysis, drain-fluid bilirubin level on day 3 after surgery was the strongest predictor of infection (odds ratio 15·11, 95 per cent confidence interval 3·04 to 92·11; P < 0·001). The area under the receiver operating characteristic curve on day 3 had the highest predictive value: 83·6 per cent accuracy and 3·9 per cent false-positive rate for a drain-fluid bilirubin level of 3·01 mg/dl (51·5 µmol/l). CONCLUSION: The '3 × 3 rule' (drain-fluid bilirubin level below 3 mg/dl on day 3 after operation) is an accurate criterion for removal of prophylactically placed abdominal drains in liver resection.


Assuntos
Drenagem/métodos , Neoplasias Hepáticas/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Bilirrubina/sangue , Remoção de Dispositivo , Hepatectomia/métodos , Humanos , Neoplasias Hepáticas/sangue , Pessoa de Meia-Idade , Infecção da Ferida Cirúrgica/sangue , Infecção da Ferida Cirúrgica/etiologia , Fatores de Tempo , Resultado do Tratamento
9.
Clin Exp Allergy ; 42(8): 1217-26, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22805469

RESUMO

BACKGROUND: Lipopolysaccharide (LPS) has shown heterogeneous effects on eosinophilic inflammation in airways. However, little is known about how LPS regulates pathogenesis of chronic rhinosinusitis with nasal polyps, a major form of eosinophilic inflammation in the upper airway. OBJECTIVE: We sought to investigate the effect of LPS on cytokine production by dispersed nasal polyp cells (DNPCs). METHODS: Either diclofenac-treated or untreated DNPCs were cultured with or without staphylococcal enterotoxin B (SEB) in the presence or absence of LPS, after which the levels of IL-5, IL-13, IL-17A and IFN-γ within the supernatant were measured. The effects of PGE(2) on LPS-induced responses by diclofenac-treated DNPCs were also examined. LPS-induced PGE(2) production and mRNA expression of COX-1, COX-2 and microsomal PGE(2) synthase-1 (m-PGES-1) were measured. RESULTS: Staphylococcal enterotoxin B induced IL-5, IL-13, IL-17A and IFN-γ production by DNPCs. Pre-treatment with LPS prior to SEB stimulation inhibited production of these cytokines. After stimulation with LPS, PGE(2) production and expression of COX-2 and m-PGES-1 mRNA by DNPCs increased significantly. In the presence of diclofenac, the suppressive effects of LPS were eliminated. LPS pre-treatment enhanced SEB-induced IL-5, IL-13 and IL-17A production in diclofenac-treated DNPCs, while addition of PGE(2) inhibited IL-5, IL-13 and IFN-γ production. LPS alone induced IL-5, IL-13 and IFN- γ production by diclofenac-treated DNPCs, while the addition of EP2 and EP4 receptor-selective agonists, as well as PGE(2) itself, inhibited IL-5 and IL-13 production. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that the regulatory effects of LPS on eosinophilic airway inflammation are controlled via the COX-2/PGE(2) axis. For clinical implications, indiscreet use of non-steroidal anti-inflammatory drugs should be avoided in patients with chronic rhinosinusitis with nasal polyps.


Assuntos
Citocinas/biossíntese , Dinoprostona/metabolismo , Eosinofilia/imunologia , Lipopolissacarídeos/imunologia , Pólipos Nasais/imunologia , Pólipos Nasais/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Adolescente , Adulto , Idoso , Células Cultivadas , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas/imunologia , Enterotoxinas/imunologia , Eosinofilia/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Prostaglandina-Endoperóxido Sintases/genética , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Adulto Jovem
10.
Clin Exp Allergy ; 41(2): 171-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21039976

RESUMO

BACKGROUND: Fungi and/or Staphylococcus aureus enterotoxins (SEs) may participate in the pathogenesis of eosinophilic inflammation in cases of chronic rhinosinusitis with nasal polyps (CRSwNP). Objective We sought to determine the effects of fungal antigens on eosinophilia-associated cellular responses in nasal polyps. METHODS: Dispersed nasal polyp cells (DNPCs) were prepared from 13 patients with CRSwNP. DNPCs were cultured with fungal extracts (Aspergillus, Alternaria and Candida) or SEB for 72 h, after which the levels of IL-5, IL-13 and RANTES were measured within the supernatant. Responses to ß-d-glucan, mannan and chitin were also examined. RESULTS: 38.5%, 69.2% and 30.8% of DNPCs produced IL-5, IL-13 and RANTES, respectively, in response to 200 µg/mL of Aspergillus. 53.8%, 53.8% and 7.7% of DNPCs produced IL-5, IL-13 and RANTES, respectively, in response to 200 µg/mL of Alternaria. 53.8%, 38.5% and 15.4% of DNPCs produced IL-5, IL-13 and RANTES, respectively, in response to 200 µg/mL of Candida. All DNPCs produced these cytokines in response to 0.1 µg/mL of SEB. SEB induced significantly greater cytokine levels than the fungal extracts. No correlation between cytokine production following exposure to each of the fungal extracts or SEB and various clinical features, including nasal polyp eosinophilia and radiological severity of sinusitis was observed. Neither sensitization to fungus nor comorbidity with bronchial asthma was correlated with the fungal extract-induced cytokine production by DNPCs. ß-d-glucan, mannan and chitin did not induce significant cytokine production. CONCLUSIONS: These results suggest that, although DNPCs produce IL-5, IL-13 and RANTES in response to fungal extracts, fungal antigens including major carbohydrates are less capable of inducing eosinophilia-associated cellular responses in nasal polyps than SEB.


Assuntos
Antígenos de Fungos/imunologia , Enterotoxinas/imunologia , Eosinofilia/imunologia , Pólipos Nasais/imunologia , Adulto , Idoso , Células Cultivadas , Citocinas/biossíntese , Citocinas/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/patologia , Adulto Jovem
11.
Clin Exp Immunol ; 163(2): 260-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21166666

RESUMO

Otitis media is one of the most common and intractable ear diseases, and is the major cause of hearing loss, especially in children. Multiple factors affect the onset or development of otitis media. Prostaglandin D2 is the major prostanoid involved in infection and allergy. However, the role of prostaglandin D2 and prostaglandin D2 receptors on the pathogenesis of otitis media remains to be determined. Recent studies show that D prostanoid receptor (DP) and chemoattractant receptor-homologous molecule expressed on T helper type 2 (Th2) cells (CRTH2) are major prostaglandin D2 receptors. In this study, homozygous DP single gene-deficient (DP⁻(/)⁻) mice, CRTH2 single gene-deficient (CRTH2⁻(/)⁻) mice and DP/CRTH2 double gene-deficient (DP⁻(/)⁻ CRTH2⁻(/)⁻) mice were used to investigate the role of prostaglandin D2 and its receptors in otitis media. We demonstrate that prostaglandin D2 is induced by lipopolysaccharide (LPS), a major component of Gram-negative bacteria, and that transtympanic injection of prostaglandin D2 up-regulates macrophage inflammatory protein 2 (MIP-2), interleukin (IL)-1ß and IL-6 in the middle ear. We also show that middle ear inflammatory reactions, including infiltration of inflammatory cells and expression of MIP-2, IL-1ß and IL-6 induced by LPS, are reduced significantly in DP⁻(/)⁻ mice and DP⁻(/)⁻ CRTH2⁻(/)⁻ mice. CRTH2⁻(/)⁻ mice display inflammatory reactions similar to wild-type mice. These findings indicate that prostaglandin D2 may play significant roles in LPS-induced experimental otitis media via DP.


Assuntos
Citocinas/imunologia , Lipopolissacarídeos/imunologia , Otite Média/imunologia , Receptores Imunológicos/imunologia , Receptores de Prostaglandina/imunologia , Animais , Quimiocina CXCL2/imunologia , Modelos Animais de Doenças , Feminino , Interleucina-1beta/imunologia , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Prostaglandina D2/imunologia , Receptores Imunológicos/genética , Receptores de Prostaglandina/genética , Células Th2/imunologia
13.
Mol Ecol Resour ; 9(3): 793-5, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-21564745

RESUMO

We developed and characterized 13 microsatellite markers from the water mite Hygrobates fluviatilis. The genotypes of 32 diploid females were assessed, and all of the loci were polymorphic. The number of alleles per locus ranged from two to 21, and the observed heterozygosity ranged from 0.063 to 0.813. These microsatellite markers are the first published for water mites and will contribute to research on the population structure of this widespread species.

14.
Clin Exp Allergy ; 38(12): 1891-900, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19016801

RESUMO

BACKGROUND: B7/CD28 family co-signalling molecules play a key role in regulating T cell activation and tolerance. Allergen-specific immunotherapy (SIT) alters allergen-specific T cell responses. However, the effect of SIT on the expression of various co-signalling molecules has not been clarified. OBJECTIVE: We sought to determine whether SIT might affect the expression of three co-inhibitory molecules, programmed death (PD)-1, B7-H1 and B and T lymphocyte attenuator (BTLA), in Japanese cedar pollinosis (JCP). METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from JCP patients who had or had not received SIT. PBMC were cultured in the presence or absence of Cry j 1, after which the cell surface expression of PD-1, B7-H1 and BTLA, as well as IL-5 production, were determined. In addition, the effect of BTLA cross-linking on IL-5 production was examined. RESULTS: After Cry j 1 stimulation, no significant differences in PD-1 and B7-H1 expression were observed between SIT-treated and SIT-untreated patients. BTLA expression was down-regulated in untreated patients after Cry j 1 stimulation and up-regulated in SIT-treated patients. Up-regulation of BTLA in SIT-treated patients was particularly apparent in a CD4(+) T cell subset. IL-5 production was clearly reduced among SIT-treated patients, and the observed changes in BTLA expression correlated negatively with IL-5 production. Moreover, immobilization of BTLA suppressed IL-5 production in JCP patients. CONCLUSION: These results suggest that both IL-5 production and down-regulation of BTLA in response to allergen are inhibited in SIT-treated patients with JCP. BTLA-mediated co-inhibition of IL-5 production may contribute to the regulation of allergen-specific T cell responses in patients receiving immunotherapy.


Assuntos
Alérgenos/administração & dosagem , Cryptomeria/imunologia , Dessensibilização Imunológica , Proteínas de Plantas/administração & dosagem , Rinite Alérgica Sazonal/terapia , Adulto , Alérgenos/imunologia , Antígenos de Plantas , Células Cultivadas , Esquema de Medicação , Feminino , Humanos , Interleucina-5/antagonistas & inibidores , Interleucina-5/biossíntese , Ativação Linfocitária , Linfócitos , Masculino , Pessoa de Meia-Idade , Proteínas de Plantas/imunologia , Receptores Imunológicos/antagonistas & inibidores , Receptores Imunológicos/biossíntese , Rinite Alérgica Sazonal/imunologia , Especificidade da Espécie , Resultado do Tratamento
15.
Protoplasma ; 230(3-4): 129-39, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17458628

RESUMO

In higher-plant cells, microtubules, actin microfilaments, and vacuoles play important roles in a variety of cellular events, including cell division, morphogenesis, and cell differentiation. These intracellular structures undergo dynamic changes in their shapes and functions during cell division and differentiation, and to analyse these sequential structural changes, the vital labelling technique, using the green-fluorescent protein or other fluorescent proteins, has commonly been used to follow the localisation and translocation of specific proteins. To visualise microtubules, actin filaments, and vacuoles, several strategies are available for selecting the appropriate fluorescent-protein fusion partner: microtubule-binding proteins, tubulin, and plus-end-tracking proteins are most suitable for microtubule labelling; the actin binding domain of mouse talin and plant fimbrin for actin microfilament visualisation; and the tonoplast-intrinsic proteins and syntaxin-related proteins for vacuolar imaging. In addition, three-dimensional reconstruction methods are indispensable for localising the widely distributed organelles within the cell. The maximum intensity projection method is suitable for cytoskeletal structures, while contour-based surface modelling possesses many advantages for vacuolar membranes. In this article, we summarise the recent progress in living cell imaging of the plant cytoskeleton and vacuoles using various fusions with green-fluorescent proteins and three-dimensional imaging techniques.


Assuntos
Citoesqueleto/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Citometria por Imagem/métodos , Plantas Geneticamente Modificadas/metabolismo , Plantas/metabolismo , Vacúolos/metabolismo , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/ultraestrutura , Citoesqueleto/ultraestrutura , Proteínas de Fluorescência Verde/genética , Citometria por Imagem/tendências , Imageamento Tridimensional , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Plantas/genética , Plantas/ultraestrutura , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/ultraestrutura , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Vacúolos/ultraestrutura
16.
J Cardiovasc Pharmacol ; 38(2): 174-82, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11483866

RESUMO

The purpose of this study was to evaluate the effects of cicletanine, a slightly diuretic antihypertensive drug, on human vascular endothelial cells with regard to nitric oxide, intracellular calcium concentration ([Ca2+]i), cyclic nucleotide, inositol 1,4,5-trisphosphate (IP3), and prostacyclin generation. Primary cultured human umbilical vein endothelial cells were used in this study. [Ca2+]i was measured by fura-2/AM. Cyclic adenosine monophosphate (AMP), cyclic guanosine monophosphate (GMP), IP3, and prostacyclin were measured by radioimmunoassay. Nitric oxide was measured by the Griess method. Cicletanine had no effect on [Ca2+]i. Cicletanine (10(-6)-10(-4) M) increased cyclic GMP but decreased prostacyclin generation. Cicletanine had no stimulating effect on cyclic AMP or IP3 generation. IP3 increased 45Ca release from storage sites. Cicletanine decreased prostacyclin generation via increase in cyclic GMP. Cicletanine had no stimulating effect on nitrogen oxides for 2 h after incubation but increased it after 3-24 h. Pretreatment with L-N(G)-monomethyl-arginine (L-NMMA) prevented this increase. The inhibitory effect of L-NMMA was prevented by pretreatment with L-arginine. These results indicate that nitric oxide and cyclic GMP may contribute to the antihypertensive action of cicletanine.


Assuntos
Anti-Hipertensivos/farmacologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Piridinas/farmacologia , Veias Umbilicais/citologia , Cálcio/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Endotélio Vascular/citologia , Epoprostenol/metabolismo , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Líquido Intracelular/efeitos dos fármacos , Líquido Intracelular/metabolismo
17.
Cancer Genet Cytogenet ; 129(1): 30-4, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11520562

RESUMO

Human B-lymphoblastoid cell lines transformed by Epstein-Barr (EBV-LCLs) are considered to be immortalized, although most of them show a normal diploid karyotype. Recently, we and others have shown that only part of EBV-LCLs is immortalized by developing strong telomerase activity that stabilizes the telomeres. In this study, we investigated the change in karyotypes during immortalization. All the eight immortalized cell lines developed clonal chromosomal aberrations accompanied by the development of strong telomerase activity. Interestingly, abnormal chromosomes were not shared among the immortalized cell lines. These results strongly suggest that chromosomal rearrangements and induction of strong telomerase activity are two events that take place in parallel in the process of immortalization of EBV-LCLs, and indicate that EBV-LCLs are clearly divided into two distinct groups, pre-immortal cell lines mostly with a normal diploid karyotype and post-immortal cell lines with a clonally abnormal karyotype.


Assuntos
Linfócitos B/ultraestrutura , Transformação Celular Viral , Aberrações Cromossômicas , Herpesvirus Humano 4/genética , Telomerase/metabolismo , Linfócitos B/enzimologia , Linhagem Celular , Humanos , Cariotipagem , Telômero
18.
Hypertension ; 36(2): 201-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10948078

RESUMO

The effects of bradykinin on the regulatory mechanisms of prostacyclin synthesis in endothelial cells were investigated in association with intracellular Ca(2+) kinetics, cytosolic phospholipase A(2) (cPLA(2)) activity, and mRNA expression of cPLA(2) and prostaglandin H synthase (PGHS) isoforms. Bradykinin enhanced prostacyclin release from endothelial cells time-dependently, but pretreatment with EGTA H-7 or HOE 140 inhibited bradykinin-induced prostacyclin release. Bradykinin increased both the influx of extracellular Ca(2+) and Ca(2+) release from the intracellular Ca(2+) storage sites. These reactions occurred within 5 minutes after bradykinin stimulation. Within 15 minutes, bradykinin activated cPLA(2) to 1.3-fold the control level. The constitutive expressions of mRNA of cPLA(2), PGHS-1, and PGHS-2 was 87, 562, and 47 amol/microg RNA, respectively. With the stimulation of bradykinin, cPLA(2) mRNA increased to 746 amol/microg RNA in 15 minutes, PGHS-1 mRNA increased to 10 608 amol/microg RNA, and PGHS-2 mRNA increased to 22 400 amol/microg RNA in 180 minutes. Pretreatment with cycloheximide superinduced cPLA(2) and PGHS-2 mRNA expression but almost completely inhibited PGHS-1. Pretreatment with EGTA had effects similar to pretreatment with cycloheximide in the case of cPLA(2) and PGHS-1 but did not affect PGHS-2. These findings suggest that the elevation of cPLA(2) activity caused by the increase of intracellular Ca(2+) concentration is important in the early phase of bradykinin-induced prostacyclin synthesis and that the mechanisms regulating cPLA(2) are different from those regulating PGHS isoforms in endothelial cells.


Assuntos
Bradicinina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Epoprostenol/biossíntese , Cálcio/metabolismo , Células Cultivadas , Citosol/efeitos dos fármacos , Citosol/enzimologia , Relação Dose-Resposta a Droga , Ácido Egtázico/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Isoenzimas/efeitos dos fármacos , Isoenzimas/genética , Isoenzimas/metabolismo , Fosfolipases A/efeitos dos fármacos , Fosfolipases A/genética , Fosfolipases A/metabolismo , Prostaglandina-Endoperóxido Sintases/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/genética , Prostaglandina-Endoperóxido Sintases/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
J Pharmacol Toxicol Methods ; 41(1): 33-41, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10507756

RESUMO

We investigated the effect of probucol on the intracellular pH ([pH]i) and proliferation of human umbilical vein endothelial cells (HUVEC), as well as their production of prostacyclin (PGI2). The addition of probucol produced a biphasic shift in [pH]i, with a brief initial acidification followed by a rapid alkaline shift. After pretreatment with EGTA, the initial decrease in [pH]i was abolished, and the subsequent increase was inhibited. After pretreatment with amiloride, only the increase of [pH]i was abolished. These results suggest that the probucol-induced increase of [pH]i was mainly dependent on Na+/H+ exchange and partly on extracellular Ca2+. In contrast, the addition of LDL produced a decrease of [pH]i. Under Ca2+-free condition, [pH]i was further decreased by LDL. In cells pretreated with amiloride, however, [pH]i was not further decreased by LDL. It was found that probucol promoted cell proliferation, and LDL inhibited cell proliferation. Addition of probucol also enhanced prostacyclin generation by HUVEC. This enhancement of PGI2 generation resulted from increased release of Ca2+ from the storage sites, due not only to increased production of inositol 1,4,5-triphosphate (IP3) but also to the increase of [pH]i. These findings may help to explain the antiatherosclerotic action of probucol.


Assuntos
Anticolesterolemiantes/farmacologia , Divisão Celular/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Probucol/farmacologia , Amilorida/farmacologia , Cálcio/metabolismo , Células Cultivadas , Ácido Egtázico/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Epoprostenol/metabolismo , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Timidina/metabolismo , Veias Umbilicais
20.
J Antibiot (Tokyo) ; 52(6): 536-41, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10470677
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