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1.
Public Health ; 186: 119-124, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32818724

RESUMO

OBJECTIVES: Women with terminal cancer are assumed to choose hospice care over aggressive treatment at the end of life. With new chemotherapy and target therapy options, it becomes more difficult to decide between hospice care and aggressive management. It is also crucial to consider the cost increases leading to severe financial burdens on healthcare systems. To better understand treatment options at the individual level, this study set out to describe trends in end-of-life care for the four leading cancers in women in Taiwan. STUDY DESIGN: This was a population-based retrospective cohort study. METHODS: The data source was obtained between January 1, 2000, and December 31, 2013, from Taiwan's National Health Insurance Research Database. We identified 98,575 women with a diagnosis of breast (18,596), colorectal (23,734), liver and biliary (28,795) or lung (27,450) cancer who had died during the study period. Hospital data for services provided in the last 6 months of life, including hospice services and aggressive managements (chemotherapy, frequent hospitalisation, emergency room [ER] visits, intensive care unit [ICU] admission and endotracheal intubation), were collected. RESULTS: Hospice utilisation increased over the study period, with 25.85%, 25.34%, 21.23% and 26.55% of female patients with breast, colorectal, liver and biliary, and lung cancer receiving hospice care, respectively. However, the number of women undergoing aggressive treatments in the last 6 months of life remained high, with the breast cancer group having the highest chemotherapy rate, the colorectal cancer group having frequent hospitalisation and the liver and biliary cancer group having frequent ER visits and ICU admissions. CONCLUSIONS: Increasing hospice utilisation among women with the four most common cancers in Taiwan indicates that hospice services have gradually become well accepted over the past 13 years; however, the real focus is on the ineffective treatment preceding hospice care, and late referral was also a notable problem.


Assuntos
Cuidados Paliativos na Terminalidade da Vida/estatística & dados numéricos , Neoplasias/terapia , Assistência Terminal/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/terapia , Neoplasias Colorretais/terapia , Feminino , Hospitalização , Humanos , Unidades de Terapia Intensiva , Neoplasias Hepáticas/terapia , Neoplasias Pulmonares/terapia , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Estudos Retrospectivos , Taiwan , Doente Terminal
2.
Br J Dermatol ; 182(5): 1205-1213, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31408190

RESUMO

BACKGROUND: Acral melanoma (AM) is the most common histopathological subtype of malignant melanoma in Asians. However, differences in the mutational profiles underlying AM and nonacral cutaneous melanoma (NAM) in Asians are not well understood. OBJECTIVES: To augment the understanding of the prevalence, patterns and associations of various mutations between different subtypes of melanoma. METHODS: We performed comprehensive genomic profiling of 409 cancer-associated genes, using next-generation sequencing, in 66 primary melanomas comprised of 45 AMs and 21 NAMs. RESULTS: Most of the AMs (n = 27/45; 60%), but only five of 21 (24%) NAMs, were triple wild-type (triple-WT) tumours. Compared with AMs, NAMs exhibited a significantly higher frequency of BRAF mutations. The frequencies of NRAS/KRAS mutations, cell-cycle aberrations, copy number gains in BIRC2, BIRC3 and BIRC5, and gains of receptor tyrosine kinase genes were significantly higher in AMs. Ulceration was found at significantly higher rates in the AMs and NAMs with cell-cycle aberrations and gains of receptor tyrosine kinase genes. Notably, cell-cycle aberrations and copy number gains in BIRC2, BIRC3 and BIRC5 were significantly associated with poor melanoma-specific survival in the 66 patients with melanoma and especially in the 45 patients with AM. Multivariate analysis showed that lymph node metastasis and cell-cycle aberrations were independent prognostic factors of melanoma-specific survival. CONCLUSIONS: This study strengthens our understanding of the patterns and clinical associations of oncogenic mutations in AMs and NAMs in Asians. What's already known about this topic? Mutation frequencies of driver genes vary between melanoma subtypes. Acral melanoma is the most common subtype of melanoma in Asians. KIT mutations and copy number variations occur more frequently in the acral subtype of melanoma than in the nonacral subtype What does this study add? NRAS/KRAS mutations, cell-cycle aberrations, copy number gains in BIRC2, BIRC3 and BIRC5, and amplifications of receptor tyrosine kinase genes were significantly enriched in acral melanoma and could be potential targets for treatment. Melanomas with cell-cycle aberrations and gains in receptor tyrosine kinase genes were significantly more likely to contain ulceration. What is the translational message? Cell-cycle aberrations and copy number gains in BIRC2, BIRC3 and BIRC5 were significantly associated with poor melanoma-specific survival. These observations should be explored further for future drug development.


Assuntos
Melanoma , Neoplasias Cutâneas , Variações do Número de Cópias de DNA , Humanos , Melanoma/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Taiwan/epidemiologia
3.
Hum Exp Toxicol ; 34(3): 289-99, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24925362

RESUMO

Resveratrol is a natural compound that affects cellular calcium (Ca(2+)) homeostasis and viability in different cells. This study examined the effect of resveratrol on cytosolic free Ca(2+) concentrations ([Ca(2+)]i) and viability in OC2 human oral cancer cells. The Ca(2+)-sensitive fluorescent dye fura-2 was used to measure [Ca(2+)]i, and water-soluble tetrazolium-1 was used to measure viability. Resveratrol evoked concentration-dependent increase in [Ca(2+)]i. The response was reduced by removing extracellular Ca(2+). Resveratrol also caused manganese-induced fura-2 fluorescence quench. Resveratrol-evoked Ca(2+) entry was inhibited by nifedipine and the protein kinase C (PKC) inhibitor GF109203X but was not altered by econazole, SKF96365, and the PKC activator phorbol 12-myristate 13 acetate. In Ca(2+)-free medium, treatment with the endoplasmic reticulum Ca(2+) pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) abolished resveratrol-evoked [Ca(2+)]i rise. Conversely, treatment with resveratrol inhibited BHQ-evoked [Ca(2+)]i rise. Inhibition of phospholipase C (PLC) with U73122 abolished resveratrol-evoked [Ca(2+)]i rise. At 20-100 µM, resveratrol decreased cell viability, which was not affected by chelating cytosolic Ca(2+)with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester. Annexin V-fluorescein isothiocyanate staining data suggest that resveratrol at 20-40 µM induced apoptosis in a concentration-dependent manner. Collectively, in OC2 cells, resveratrol induced [Ca(2+)]i rise by evoking PLC-dependent Ca(2+) release from the endoplasmic reticulum and by causing Ca(2+) entry via nifedipine-sensitive, PKC-regulated mechanisms. Resveratrol also caused Ca(2+)-independent apoptosis.


Assuntos
Cálcio/metabolismo , Estilbenos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citosol/metabolismo , Humanos , Neoplasias Bucais , Proteína Quinase C/metabolismo , Resveratrol , Fosfolipases Tipo C/metabolismo
4.
Osteoporos Int ; 25(2): 673-80, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23943167

RESUMO

UNLABELLED: While alendronate inhibits atherosclerosis experimentally, its effect on lower limb ischemia risk is unknown. Our results suggest that alendronate reduces the risk of lower limb ischemic vascular events requiring surgical interventions, including amputation. Our results are relevant for patients at risk of lower limb ischemia undergoing fragility fracture treatment. INTRODUCTION: This study aimed to determine the association between alendronate therapy and the risk of lower limb ischemic vascular events (i.e., bypass surgery, endovascular stenting, and major lower limb amputation for lower limb ischemia). METHODS: We used a nationwide population-based cohort of patients aged over 50 years diagnosed with a vertebral or hip fracture between January 1999 and June 2010. We compared the risk of lower limb ischemic vascular events between patients undergoing treatment with alendronate (n = 3,731) and an age- and sex-matched comparison group (n = 7,462) over 5 years of follow-up. Hazard ratios (HR) were estimated using Cox proportional regression analysis with adjustment for treatment status, comorbidities, and other variables. RESULTS: Ten patients (0.3 %) in the alendronate treatment group had a lower limb ischemic vascular event compared with 51 patients (0.7 %) in the comparison group. The incidence of lower limb ischemic vascular events was 8.4 (95 % CI, 4.0-15.5) per 10,000 person-years in the alendronate group and 21.8 (95 % CI, 16.2-28.7) per 10,000 person-years in the comparison group. The risk of a lower limb ischemic vascular event in the alendronate treatment group was lower (adjusted HR, 0.41; 95 % CI, 0.21-0.82). CONCLUSION: Alendronate treatment was associated with a reduced risk of lower limb ischemic vascular events among hip or vertebral fragility fracture patients.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Isquemia/prevenção & controle , Extremidade Inferior/irrigação sanguínea , Idoso , Idoso de 80 Anos ou mais , Alendronato/administração & dosagem , Amputação Cirúrgica/estatística & dados numéricos , Conservadores da Densidade Óssea/administração & dosagem , Estudos de Coortes , Esquema de Medicação , Feminino , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/prevenção & controle , Humanos , Incidência , Isquemia/epidemiologia , Isquemia/cirurgia , Extremidade Inferior/cirurgia , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Medição de Risco/métodos , Sensibilidade e Especificidade , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/prevenção & controle , Taiwan/epidemiologia
5.
Hum Exp Toxicol ; 28(5): 301-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19661262

RESUMO

The effect of thimerosal on cytosolic free Ca(2+) concentrations ([Ca(2+)](i) ) in human oral cancer cells (OC2) is unclear. This study explored whether thimerosal changed basal [Ca(2+)](i) levels in suspended OC2 cells using fura-2. Thimerosal at concentrations between 1and 50 microM increased [Ca(2+)](i) in a concentration-dependent manner. The Ca(2+) signal was reduced partly by removing extracellular Ca( 2+). Thimerosal-induced Ca(2+) influx was not blocked by L-type Ca(2+) entry inhibitors and protein kinase C modulators (phorbol 12-myristate 13-acetate [PMA] and GF109203X). In Ca(2+)-free medium, 50 microM thimerosal failed to induce a [Ca(2+)](i) rise after pretreatment with thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor). Inhibition of phospholipase C with U73122 did not change thimerosal-induced [Ca(2+)](i) rises. At concentrations between 5 and 10 microM, thimerosal killed cells in a concentration-dependent manner. The cytotoxic effect of 8 muM thimerosal was potentiated by prechelating cytosolic Ca(2+) with the Ca(2+) chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetate/acetomethyl (BAPTA/ AM). Flow cytometry data suggested that 1-7 microM thimerosal-induced apoptosis in a concentration-dependent manner. Collectively, in OC2 cells, thimerosal-induced [Ca(2+)](i) rises by causing phospholipase C-independent Ca(2+) release from the endoplasmic reticulum and Ca(2+) influx through non-L-type Ca(2+) channels. Thimerosal killed cells in a concentration-dependent manner through apoptosis.


Assuntos
Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Bucais/patologia , Timerosal/toxicidade , Apoptose/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/efeitos dos fármacos , Linhagem Celular Tumoral , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/patologia , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Humanos , Inibidores de Fosfodiesterase/farmacologia , Proteína Quinase C/antagonistas & inibidores , Pirrolidinonas/farmacologia , Tapsigargina/farmacologia , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/metabolismo
6.
Eur J Clin Microbiol Infect Dis ; 27(4): 307-10, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18157678

RESUMO

Cryptococcus neoformans usually causes disease in patients with human immunodeficiency virus (HIV) infection. This descriptive study was based on a retrospective review of 33 HIV-uninfected patients with disseminated cryptococcosis from 1998 to 2005. An underlying condition associated with immunocompromise was documented in 30 patients (90.9%), including liver cirrhosis (36.4%), diabetes mellitus (33.3%) and autoimmune disease (27.3%). Disseminated cryptococcosis carried a high mortality rate in this series, reaching 63% overall, with a median survival of 21 days. All patients (12/12) with liver cirrhosis died within the first month after the diagnosis of cryptococcosis. Otherwise, high Acute Physiology and Chronic Health Evaluation II (APACHE II) score, female gender and smoking history were associated with worse one-month outcome.


Assuntos
Criptococose/complicações , Infecções por HIV , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/uso terapêutico , Criança , Criptococose/tratamento farmacológico , Feminino , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade
7.
J Orthop Surg (Hong Kong) ; 15(3): 315-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18162678

RESUMO

PURPOSE: To review the functional and radiological results of patients after coracoclavicular ligament reconstruction. METHODS: Five patients aged 21 to 50 (mean, 37) years with acute Rockwood type-III acromioclavicular dislocation underwent coracoclavicular ligament reconstruction with autogenous gracilis tendon grafts. Patients were either active in sports or heavy manual workers. Assessments on shoulder function (using the Constant score), wound size, pain (using a visual analogue scale), and reduction (using radiographs of both acromioclavicular joints) were made. RESULTS: The mean follow-up period was 26 (range, 15-43) months; the mean time to return to work or sports was 14 (range, 12-20) weeks. The mean Constant score was 94 (range, 90-98). The mean donor-site scar size was 3 cm and the mean pain score was 0. No major complication or donor-site morbidity was noted. There was one subluxation. CONCLUSION: Coracoclavicular ligament reconstruction using an autogenous gracilis tendon graft was safe in physically active patients having acute type-III acromioclavicular dislocation.


Assuntos
Articulação Acromioclavicular/lesões , Articulação Acromioclavicular/cirurgia , Luxações Articulares/cirurgia , Transferência Tendinosa/métodos , Adulto , Humanos , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Transplante Autólogo
8.
Spinal Cord ; 45(2): 174-82, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16505827

RESUMO

STUDY DESIGN: Clinicopathological correlation of three cases of subacute cervical spinal cord contusions. OBJECTIVE: To correlate the pathology of subacute cervical spinal cord injury (SCI) with imaging and clinical-functional studies, and to compare with findings from previous human SCI studies and animal models of SCI. SETTING: Department of Pathology, SUNY-Upstate Medical University, Syracuse, NY, USA. METHOD: Post mortem pathology report. CASE REPORT/RESULTS: The clinical, radiological, and pathological findings of three cases of subacute spinal cord contusions are described in detail. The postinjury survival periods were 15, 20, and 60 days, respectively. Extensive microglia/macrophage infiltrations without significant lymphocytes are seen in all cases. Free radical injury as assessed by immunocytochemistry for 4-hydroxynonenal and nitrotyrosine showed a labeling pattern parallel to that of the macrophage distribution at 15 days, but no significant labeling in the injury sites at 20 and 60 days. CONCLUSION: The present report, though limited in sample size, shows plenty of activated microglia/macrophages in human SCI up to 60 days postinjury. This observation not only confirms similar findings in previous studies, but also raises an intriguing question of potential interactions between these activated microglia/macrophages and the experimental therapy, proposed by some authors, of injecting exogenously activated macrophages to promote SCI repair. The small number of human SCI cases (in this as well as in most other single medical centers) available for detailed study illustrates the need for the establishment of a consortium of human SCI tissue banks.


Assuntos
Linfócitos/patologia , Macrófagos/patologia , Traumatismos da Medula Espinal/patologia , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Coloração e Rotulagem/métodos
9.
J Recept Signal Transduct Res ; 26(3): 199-212, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16777715

RESUMO

The effect of the carcinogen safrole on intracellular Ca2+ mobilization and on viability of human PC3 prostate cancer cells was examined. Cytosolic free Ca2+ levels ([Ca2+]i) were measured by using fura-2 as a probe. Safrole at concentrations above 10 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 350 microM. The Ca2+ signal was reduced by more than half after removing extracellular Ca2+ but was unaffected by nifedipine, nicardipine, nimodipine, diltiazem, or verapamil. In Ca2+-free medium, after treatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release Ca2+. Neither inhibition of phospholipase C with U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 0.65-65 microM safrole did not affect cell viability, but incubation with 325-625 microM safrole decreased viability. Collectively, the data suggest that in PC3 cells, safrole induced a [Ca2+]i increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx. Safrole can decrease cell viability in a concentration-dependent manner.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Safrol/toxicidade , Bloqueadores dos Canais de Cálcio/farmacologia , Carcinógenos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteína Quinase C/metabolismo , Fosfolipases Tipo C/metabolismo
10.
Hum Exp Toxicol ; 24(9): 453-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16235734

RESUMO

Econazole is an antifungal drug with different in vitro effects. However, econazole's effect on osteoblast-like cells is unknown. In human MG63 osteosarcoma cells, the effect of econazole on intracellular Ca2+ concentrations ([Ca2+]i) was explored by using fura-2. At a concentration of 0.1 microM, econazole started to cause a rise in [Ca2+]i in a concentration-dependent manner. Econazole-induced [Ca2+]i rise was reduced by 74% by removal of extracellular Ca2+. The econazole-induced Ca2+ influx was mediated via a nimodipine-sensitive pathway. In Ca2+ -free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca+ -ATPase, caused a [Ca2+]i rise, after which the increasing effect of econazole on [Ca2+]i was abolished. Pretreatment of cells with econazole to deplete Ca2+ stores totally prevented thapsigargin from releasing Ca2+. U73122, an inhibitor of phospholipase C, abolished histamine (an inositol 1,4,5-trisphosphate-dependent Ca2+ mobilizer)-induced, but not econazole-induced, [Ca2+]i rise. Econazole inhibited 76% of thapsigargin-induced store-operated Ca2+ entry. These findings suggest that in MG63 osteosarcoma cells, econazole increases [Ca2+]i by stimulating Ca2+ influx and Ca2+ release from the endoplasmic reticulum via a phospholipase C-independent manner. In contrast, econazole acts as a potent blocker of store-operated Ca2+ entry.


Assuntos
Antifúngicos/farmacologia , Cálcio/metabolismo , Econazol/farmacologia , Neoplasias Ósseas , Bloqueadores dos Canais de Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Nimodipina/farmacologia , Osteossarcoma , Tapsigargina/farmacologia , Fatores de Tempo
11.
Pharmacol Res ; 44(6): 547-52, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11735364

RESUMO

The effect of histamine on intracellular free Ca2+ levels ([Ca2+]i) in PC3 human prostate cancer cells and the underlying mechanism were evaluated using fura-2 as a Ca2+ dye. Histamine at concentrations between 0.1 and 50 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 1 microM. The [Ca2+]i response comprised an initial rise and a slow decay, which returned to baseline within 3 min. Extracellular Ca2+ removal inhibited 50% of the [Ca2+]i signal. In the absence of extracellular Ca2+, after cells were treated with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), 10 microM histamine did not increase [Ca2+]i. After pretreatment with 10 microM histamine in a Ca2+-free medium for several minutes, addition of 3 mM Ca2+ induced [Ca2+]i increases. Histamine (10 microM)-induced intracellular Ca2+ release was abolished by inhibiting phospholipase C with 2 microM 1-(6-((17 beta-3- methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122), and by 10 microM pyrilamine but was not altered by 50 microM cimetidine. Collectively, the present study shows that histamine induced [Ca2+]i transients in PC3 human prostate cancer cells by stimulating H1 histamine receptors leading to Ca2+ release from the endoplasmic reticulum in an inositol 1,4,5-trisphosphate-dependent manner, and by inducing Ca2+ entry.


Assuntos
Cálcio/metabolismo , Histamina/metabolismo , ATPases Transportadoras de Cálcio/antagonistas & inibidores , Retículo Endoplasmático/metabolismo , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Corantes Fluorescentes , Fura-2 , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores H2 da Histamina/farmacologia , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Transporte de Íons , Masculino , Inibidores de Fosfodiesterase/farmacologia , Neoplasias da Próstata , Pirilamina/farmacologia , Pirrolidinonas/farmacologia , Tapsigargina/farmacologia , Células Tumorais Cultivadas , Fosfolipases Tipo C/antagonistas & inibidores
12.
J Recept Signal Transduct Res ; 21(1): 1-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11693169

RESUMO

The effect of histamine on intracellular free Ca2+ levels ([Ca2+]i) in Chang liver cells were investigated by using fura-2 as a Ca2+ dye. Histamine (0.2-50 microM) increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 0.8 microM. The [Ca2+]i response comprised an initial rise, a slow decay, and a sustained phase. Extracellular Ca2+ removal inhibited 50% of the maximum [Ca2+]i signal and abolished the sustained phase. After pretreatment with 5 microM histamine in Ca2+-free medium for 4 min, addition of 3 mM Ca2+ induced a [Ca2+]i increase with a magnitude 7-fold greater than control. In Ca2+-free medium, after treatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), 5 microM histamine failed to increase [Ca2+]i. Histamine (5 microM)-induced intracellular Ca2+ release was abolished


Assuntos
Cálcio/metabolismo , Histamina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , ATPases Transportadoras de Cálcio/antagonistas & inibidores , Linhagem Celular , Cimetidina/farmacologia , Espaço Extracelular/metabolismo , Corantes Fluorescentes , Fura-2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Líquido Intracelular/efeitos dos fármacos , Líquido Intracelular/metabolismo , Cinética , Pirilamina/farmacologia , Receptores Histamínicos H1/efeitos dos fármacos , Receptores Histamínicos H1/metabolismo , Receptores Histamínicos H2/efeitos dos fármacos , Receptores Histamínicos H2/metabolismo , Espectrometria de Fluorescência , Tapsigargina/farmacologia
13.
Hum Exp Toxicol ; 20(7): 359-64, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11530834

RESUMO

This study investigated the effect of the anti-anginal drug, fendiline, on intracellular free Ca2+ levels ([Ca2+]i) in HA/ 22 human hepatoma cells by using fura-2 as a fluorescent Ca2+ dye. Fendiline (1-100 microM) increased [Ca2+]i with an EC50 of 25 microM. Removal of extracellular Ca2+ reduced the [Ca2+]i signals by 51 +/- 5%. Fendiline (10 microM)-induced Ca2+ release was abolished by pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor). Inhibition of phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122) did not alter 10 microM fendiline-induced Ca2+ release. Several other calmodulin antagonists, such as phenoxybenzamine (100-200 microM), trifluoperazine (5-50 microM), and fluphenazine-N-chloroethane (2-100 microM), had no effect on [Ca2+]i. Together, it was found that fendiline increased [Ca2+]i in human hepatoma cells by discharging Ca2+ from the endoplasmic reticulum in an inositol 1,4,5-trisphosphate-independent manner and by inducing Ca2+ entry. This effect of fendiline does not appear to be via antagonism of calmodulin.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Cálcio/farmacocinética , Carcinoma Hepatocelular/patologia , Fendilina/farmacologia , Neoplasias Hepáticas/patologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/fisiologia , Humanos , Transdução de Sinais , Células Tumorais Cultivadas
14.
Chin J Physiol ; 44(2): 67-72, 2001 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-11530946

RESUMO

The effect of clomiphene, an ovulation-inducing agent, on cytosolic free Ca2+ levels ([Ca2+]i) in MG63 human osteosarcoma cells was explored by using fura-2 as a Ca2+ indicator. Clomiphene at concentrations between 5-75 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 of 50 microM. The [Ca2+]i signal consisted of an initial rise and a sustained phase. Ca2+ removal reduced the Ca2+ signal by 40+/-10%. The [Ca2+]i increase induced by 50 microM clomiphene was inhibited by 80+/-5% by 10 microM nifedipine, but was insensitive to 50 microM La3+ or 10 microM verapamil. In Ca2+-free medium, pretreatment with 50 microM brefeldin A (to disrupt the Golgi complex Ca2+ store), 1 microM thapsigargin (to inhibit the endoplasmic reticulum Ca2+ pump), and carbonylcyanide m-chlorophenylhydrazone (CCCP; to uncouple mitochondria) inhibited 51+/-3% of 50 microM clomiphene-induced Ca2+ release; conversely, pretreatment with 50 microM clomiphene abolished the [Ca2+]i increase induced by thapsigargin, CCCP, and brefeldin A. The Ca2+ release-induced by 50 pM clomiphene was unchanged by inhibition of phospholipase C with 2 microM 1-(6-((17beta-3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione (U73122). Collectively, the results suggest that clomiphene increased [Ca2+]i, in osteoblast-like cells, by releasing intracellular Ca2+ in a phospholipase C-independent manner and by causing nifedipine-sensitive Ca2+ influx.


Assuntos
Cálcio/metabolismo , Clomifeno/farmacologia , Fármacos para a Fertilidade Feminina/farmacologia , Membranas Intracelulares/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Quelantes/farmacologia , Ácido Egtázico/farmacologia , Estrenos/farmacologia , Espaço Extracelular/metabolismo , Humanos , Concentração Osmolar , Inibidores de Fosfodiesterase/farmacologia , Pirrolidinonas/farmacologia , Células Tumorais Cultivadas , Fosfolipases Tipo C/antagonistas & inibidores
15.
Cancer Chemother Pharmacol ; 48(1): 37-41, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11488522

RESUMO

BACKGROUND: The effects of the anti-anginal drug fendiline on intracellular Ca2+ concentrations ([Ca2+]i) in human PC3 prostate cancer cells were examined. METHODS: [Ca2+]i was measured using the fluorescent dye fura-2. RESULTS: Fendiline (0.5-100 microM) increased [Ca2+]i in a concentration-dependent manner. Ca2+ removal partly inhibited the Ca2+ signals. In Ca2+-free medium, pretreatment with 100 microM fendiline inhibited most of the [Ca2+]i increase induced by 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), and pretreatment with thapsigargin abolished the fendiline-induced [Ca2+]i increases. Adding 3 mM Ca2+ increased [Ca2+]i in cells pretreated with 0.5-200 microM fendiline in Ca2+-free medium. Pretreatment with 1 microM U73122 to block the formation of inositol-1.4.5-trisphosphate (IP3) did not alter fendiline-induced internal Ca2+ release. CONCLUSIONS: The anti-anginal drug fendiline induced internal Ca2+ release and external Ca2+ entry. Because prolonged increases in [Ca2+]i may lead to cell injury and death, the long-term effect of fendiline on the function of prostate cancer cells should be investigated.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Cálcio/metabolismo , Fendilina/farmacologia , Neoplasias da Próstata/metabolismo , Vasodilatadores/farmacologia , Trifosfato de Adenosina/farmacologia , Humanos , Inositol 1,4,5-Trifosfato/biossíntese , Masculino , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas
16.
Toxicol Lett ; 122(3): 245-53, 2001 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-11489359

RESUMO

The effect of the estrogen diethylstilbestrol (DES) on cytosolic free Ca(2+) levels ([Ca(2+)](i)) in MG63 human osteoblasts was explored by using fura-2 as a Ca(2+) indicator. DES at concentrations between 5--20 microM induced an immediate increase in [Ca(2+)](i) in a concentration-dependent manner with an EC(50) of 10 microM. Removing extracellular Ca(2+) reduced the Ca(2+) signal by 70%. Pretreatment with 50 microM La(3+) or 10 microM of nifedipine, verapamil and diltiazem did not change 20 microM DES-induced [Ca(2+)](i) increases. Addition of 3 mM Ca(2+) increased [Ca(2+)](i) in cells pretreated with 20 microM DES in Ca(2+)-free medium. Pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor) to deplete the endoplasmic reticulum Ca(2+) store partly inhibited 20 microM DES-induced Ca(2+) release, but addition of carbonylcyanide m-chlorophenylhydrazone (CCCP; a mitochondrial uncoupler) and thapsigargin together abolished DES-induced Ca(2+) release. Conversely, pretreatment with 20 microM DES abrogated CCCP- and thapsigargin-induced Ca(2+) release. Inhibition of phospholipase C activity with 2 microM U73122 did not alter 20 microM DES-induced Ca2+ release. Another estrogen 17beta-estradiol also increased [Ca(2+)](i) in a concentration-dependent manner with an EC50 of 7 microM. Together, the data indicate that in human osteoblasts, DES increased [Ca(2+)](i) via causing Ca(2+) release from both mitochondria and the endoplasmic reticulum in a phospholipase C-independent manner, and by causing Ca(2+) influx.


Assuntos
Cálcio/metabolismo , Dietilestilbestrol/farmacologia , Osteoblastos/efeitos dos fármacos , Osteossarcoma/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Estradiol/farmacologia , Fura-2/metabolismo , Humanos , Lantânio/farmacologia , Osteoblastos/metabolismo , Células Tumorais Cultivadas , Fosfolipases Tipo C/metabolismo
17.
Arch Toxicol ; 75(3): 184-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11409540

RESUMO

This study examined the effect of tamoxifen, an anti-breast cancer drug, on Ca2+ handling in bladder female transitional cancer cells. Changes in cytosolic free Ca2+ levels were recorded by using the Ca2+-sensitive dye fura-2. In a dose-dependent manner, tamoxifen induced intracellular free Ca2+ concentrations ([Ca2+]i) increases between 5 and 20 microM with an EC50 of 10 microM. External Ca2+ removal reduced the response by 60+/-6%. Addition of 3 mM Ca2+ caused a [Ca2+]i increase after pretreatment with 10 microM tamoxifen in Ca2+-free medium. In Ca2+-free medium, pretreatment with 10 microM tamoxifen abolished the [Ca2+]i increase induced by 1 microM thapsigargin, an endoplasmic reticulum Ca2+ pump inhibitor. Conversely, pretreatment with 1 microM thapsigargin prevented tamoxifen from releasing more Ca2+. Inhibition of phospholipase C-dependent inositol 1,4,5-tris-phosphate formation with 2 microM U73122 did not alter 10 microM tamoxifen-induced Ca2+ release. The [Ca2+]i increase induced by 5 microM tamoxifen was not altered by 10 microM La3+, nifedipine, verapamil, and diltiazem. Collectively, it was found that tamoxifen increased [Ca2+]i in bladder cancer cells by releasing Ca2+ from the endoplasmic reticulum Ca2+ stores in a manner independent of phospholipase C activity, and by inducing Ca2+ entry from external medium.


Assuntos
Anticarcinógenos/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Carcinoma de Células de Transição/metabolismo , Tamoxifeno/farmacologia , Neoplasias da Bexiga Urinária/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Corantes Fluorescentes , Fura-2 , Humanos , Pirrolidinonas/farmacologia , Tapsigargina/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Fosfolipases Tipo C/antagonistas & inibidores
18.
Pharmacol Res ; 43(5): 503-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11394944

RESUMO

The effect of the antidepressant fluoxetine on Ca2+ signaling in cultured cells was largely unknown. The effect of various concentrations of fluoxetine on [Ca 2+] i in populations of bladder female transitional cancer (BFTC) cells was evaluated by using fura-2 as a Ca2+ probe. Fluoxetine increased [Ca 2+] i concentration dependently (20-100 microM) with an EC50 value of 30 microM. The response was inhibited by 50-60% on extracellular Ca2+ removal. In Ca2+ -free medium, pretreatment with 1 microM thapsigargin (an inhibitor of the endoplasmic reticulum Ca2+ pump) abolished 50 microM fluoxetine-induced Ca2+ release; whereas pretreatment with fluoxetine did not alter the thapsigargin-induced Ca2+ response. Addition of 3 mM Ca2+ increased [Ca 2+] i after pretreatment with 50 microM fluoxetine in Ca2+ -free medium, suggestive of fluoxetine-induced capacitative Ca2+ entry. Suppression of inositol 1,4,5-trisphosphate formation by 2 microM U73122 (a phospholipase C inhibitor) did not affect 50 microM fluoxetine-induced Ca2+ release. Collectively, this study shows that fluoxetine increased [Ca 2+] i in bladder cancer cells in a concentration-dependent fashion, by releasing Ca2+ from thapsigargin-sensitive Ca2+ stores in an IP3-independent manner, and by inducing Ca2+ influx from extracellular medium.


Assuntos
Cálcio/metabolismo , Carcinoma de Células de Transição/metabolismo , Fluoxetina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Neoplasias da Bexiga Urinária/metabolismo , Carcinoma de Células de Transição/patologia , Linhagem Celular , Estrenos/farmacologia , Feminino , Humanos , Indicadores e Reagentes , Inositol 1,4,5-Trifosfato/metabolismo , Pirrolidinonas/farmacologia , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/patologia
19.
Chin J Physiol ; 44(3): 97-101, 2001 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-11767287

RESUMO

The effect of the antifungal drug bifonazole on Ca2+ homeostasis in Madin Darby canine kidney (MDCK) cells was investigated. Cell suspensions were loaded with the Ca2+-sensitive dye fura-2, and the fluorescence changes were measured with a spectrofluorophotometer. At concentrations between 10-80 microM bifonazole increased cytosolic free Ca2+ levels ([Ca2+]i) in a concentration-dependent manner. The Ca2+ signals were partly inhibited by removing extracellular Ca2+. Bifonazole (40 microM) released Ca2+ from the store sensitive to 1 microM thapsigargin, an endopolasmic reticulum Ca2+ pump inhibitor. Bifonazole (40 microM) per se induced capacitative Ca2+ entry while reduced 1 microM thapsigargin-induced capacitative Ca2+ entry. Inositol 1,4,5-trisphosphate may be involved in bifonazole-induced Ca2+ release because inhibiting phospholipase C with 2 microM U73122 partly reduced the bifonazole response. Together, bifonazole increased [Ca2+]i in renal tubular cells by inducing intracellular Ca2+ release and extracellular Ca2+ influx.


Assuntos
Antifúngicos/administração & dosagem , Cálcio/metabolismo , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Imidazóis/administração & dosagem , Túbulos Renais/citologia , Túbulos Renais/metabolismo , Trifosfato de Adenosina/administração & dosagem , Animais , Cães , Relação Dose-Resposta a Droga , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Inibidores Enzimáticos/farmacologia , Inositol 1,4,5-Trifosfato/biossíntese , Modelos Animais , Tapsigargina/administração & dosagem , Fatores de Tempo , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/efeitos dos fármacos
20.
Hum Pathol ; 31(7): 876-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10923929

RESUMO

An 80-year old man presented with shortness of breath and was found to have a large right pleural effusion. Cytology of the pleural fluid showed atypical papillary clusters of epithelioid cells. Multiple white-yellow nodules studding the pleural surfaces were seen at thoracoscopy, and biopsies showed solid and papillary clusters of large epithelioid cells with abundant cytoplasm filled with clear vacuoles. Special stains and electron microscopic findings indicated that the tumor was a diffuse malignant mesothelioma with numerous intracytoplasmic lipid vacuoles. Fat stain may be useful at time of frozen section for a pleural-based tumor with vacuolated cells, and the presence of lipid vacuoles in a pleural-based tumor does not exclude diffuse malignant mesothelioma.


Assuntos
Mesotelioma/patologia , Neoplasias Pleurais/patologia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Corantes , Citoplasma/patologia , Células Epiteliais/patologia , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Derrame Pleural/patologia , Vacúolos/patologia
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