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1.
Ann R Coll Surg Engl ; 102(5): e102-e104, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32159370

RESUMO

Epigastric hernia involving the falciform ligament is exceptionally rare. Most reported cases are incisional hernia secondary to prior abdominal surgery. We report a case of primary falciform ligament herniation into the epigastric region repaired by the laparoscopic preperitoneal approach. In this case, an accompanying vessel along the herniated falciform ligament was identified. This finding provides a basis for the hypothesis of a perforating vessel piercing the linea alba and thereby creating a weak point for hernia protrusion (Moschowitz theory). The patient had an uneventful recovery and was discharged home on the postoperative day two. A laparoscopic preperitoneal approach is feasible for the repair of primary falciform ligament herniation. The magnified endoscopic view enables surgeons to achieve definite repair without missing occult defects.


Assuntos
Parede Abdominal/patologia , Hérnia Abdominal/cirurgia , Laparoscopia , Ligamentos/patologia , Parede Abdominal/diagnóstico por imagem , Parede Abdominal/cirurgia , Idoso , Feminino , Hérnia Abdominal/diagnóstico , Hérnia Abdominal/patologia , Humanos , Ligamentos/diagnóstico por imagem , Resultado do Tratamento , Ultrassonografia
2.
Chin J Physiol ; 59(5): 268-275, 2016 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-27604137

RESUMO

NPC15199 is a synthesized compound that inhibits inflammation in some models. However, whether NPC15199 affects Ca²âº homeostasis in human gastric cancer is unclear. This study examined the effect of NPC15199 on cytosolic free Ca²âº concentrations ([Ca²âº]i) and viability in SCM1 human gastric cancer cells. The Ca²âº-sensitive fluorescent dye fura-2 was used to measure [Ca²âº]i. NPC15199 evoked [Ca²âº]i rises concentration-dependently. The response was reduced by removing extracellular Ca²âº. NPC15199-evoked Ca²âº entry was not inhibited by store-operated channel inhibitors (nifedipine, econazole and SKF96365) and protein kinase C (PKC) activator (phorbol 12-myristate 13 acetate, PMA), or PKC inhibitor (GF109203X). In Ca²âº-free medium, treatment with the endoplasmic reticulum Ca²âº pump inhibitor thapsigargin or 2,5-di-tert-butylhydroquinone (BHQ) nearly abolished NPC15199-evoked [Ca²âº]i rises. Conversely, treatment with NPC15199 also nearly abolished thapsigargin or BHQ-evoked [Ca²âº]i rises. Inhibition of phospholipase C (PLC) with U73122 did not affect NPC15199-evoked [Ca²âº]i rises. NPC15199 at concentrations of 100-900 µM induced concentration-dependent, Ca²âº-independent decrease in viability. Together, in SCM1 cells, NPC15199 induced [Ca²âº]i rises that involved Ca²âº entry through PKC-insensitive non-store-operated Ca²âº channels and PLC-independent Ca²âº release from the endoplasmic reticulum. NPC15199 also induced Ca²âº-independent cell death.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Fluorenos/uso terapêutico , Leucina/análogos & derivados , Neoplasias Gástricas/tratamento farmacológico , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Fluorenos/farmacologia , Humanos , Leucina/farmacologia , Leucina/uso terapêutico , Fosfolipases Tipo C/metabolismo
5.
Genet Mol Res ; 12(3): 4046-59, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24089094

RESUMO

The amphidromous goby Sicyopterus japonicus is distributed throughout southern Taiwan and Japan. Larvae of this freshwater fish go through a long marine stage. This migratory mode influences population genetic structure. We examined the genetic diversity, population differentiation, and demographic history of S. japonicus based on the mitochondrial DNA control region. We identified 102 haplotypes from 107 S. japonicus individuals from 22 populations collected from Taiwan and Islet Lanyu. High mean haplotype diversity (h = 0.999) versus low nucleotide diversity (θπ = 0.008) was detected across populations. There was low correspondence between clusters identified in the neighbor-joining tree and geographical region, as also indicated by AMOVA and pairwise F(ST) estimates. Both mismatch distribution analysis and Tajima's D test indicated that S. japonicus likely experienced a demographic expansion. Using a Bayesian skyline plot approach, we estimated the time of onset of the expansion of S. japonicus at 135 kyr (during the Pleistocene) and the time of stable effective population size at approximately 2.5 kyr (last glacial maximum). Based on these results, we suggest 1) a panmictic population at the oceanic planktonic larval stage, mediated by the Kuroshio current; 2) a long planktonic marine stage and long period of dispersal, which may have permitted efficient tracking of environmental shifts during the Pleistocene; and 3) a stable, constant population size ever since the last glacial maximum.


Assuntos
DNA Mitocondrial/genética , Perciformes/classificação , Perciformes/genética , Animais , Variação Genética , Haplótipos , Filogenia , Filogeografia , Densidade Demográfica , Análise de Sequência de DNA , Taiwan
6.
Hum Exp Toxicol ; 31(12): 1251-61, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22653687

RESUMO

The effect of the natural compound phenethyl isothiocyanate (PEITC) on cytosolic Ca(2+) concentrations ([Ca(2+)](i)) and viability in MDCK renal cells is unknown. This study explored whether PEITC changed [Ca(2+)](i) in MDCK cells using the Ca(2+)-sensitive fluorescent dye fura-2. PEITC at 200-700 µM increased [Ca(2+)](i) in a concentration-dependent manner. The signal was reduced by removing extracellular Ca(2+). PEITC-induced Ca(2+) influx was inhibited by nifedipine, econazole, SK&F 96365 and protein kinase C modulators. In Ca(2+)-free medium, treatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) or 2,5-di-tert-butylhydroquinone (BHQ) inhibited PEITC-induced rise in [Ca(2+)](i). Incubation with PEITC also inhibited TG or BHQ-induced rise in [Ca(2+)](i). Inhibition of phospholipase C with U73122 abolished PEITC-induced rise in [Ca(2+)](i). At 15-75 µM, PEITC decreased viability. The cytotoxic effect of PEITC was enhanced by chelating cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid/acetoxymethyl ester. Annexin V-FITC data suggest that 20 and 50 µM PEITC induced apoptosis. At 10 and 15 µM, PEITC did not increase reactive oxygen species (ROS) production. Together, in renal tubular cells, PEITC-induced rise in [Ca(2+)](i) by inducing phospholipase C-dependent Ca(2+) release from endoplasmic reticulum and Ca(2+) entry via store-operated Ca(2+) channels. PEITC induced apoptosis in a concentration-dependent, ROS/Ca(2+)-independent manner.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Inibidores Enzimáticos/toxicidade , Isotiocianatos/toxicidade , Túbulos Renais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Citosol/efeitos dos fármacos , Citosol/metabolismo , Cães , Econazol/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Imidazóis/farmacologia , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Células Madin Darby de Rim Canino , Nifedipino/farmacologia , Tapsigargina/farmacologia
7.
Eur J Clin Microbiol Infect Dis ; 29(4): 471-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20108018

RESUMO

This nationwide surveillance of clinically important bacteria from the intensive care units (ICUs) of major teaching hospitals throughout Taiwan investigated the susceptibilities to doripenem and other comparator carbapenems from September through November 2005. Minimum inhibitory concentrations (MICs) were determined for 1,311 clinical isolates using the broth microdilution method according to Clinical and Laboratory Standards Institute (CLSI) 2005 guidelines. Doripenem showed similar (within four-fold difference of MICs) in vitro activity to meropenem for Enterobacteriaceae and probably comparable activity to meropenem against important nosocomial non-fermentative Gram-negative bacilli (NFGNBs), including Pseudomonas aeruginosa, Acinetobacter baumannii and Burkholderia cepacia. Among the four carbapenems analysed, doripenem and meropenem exhibited better in vitro activity than imipenem or ertapenem against extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae and Escherichia coli isolates. However, the meropenem MIC(90) against ESBL-producing K. pneumoniae isolates was 2 microg/ml. Besides, doripenem with the MIC(90) of 0.5 microg/ml to Streptococcus pneumoniae possibly suggested its potential therapeutic effect regarding community-acquired pneumonia. Because of the heavy resistance burden in Taiwan, closely monitoring the evolutionary trend of carbapenem susceptibilities against clinically important pathogens is crucial in the future.


Assuntos
Antibacterianos/farmacologia , Infecções Bacterianas/microbiologia , Carbapenêmicos/farmacologia , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Farmacorresistência Bacteriana , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Hospitais de Ensino , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Prevalência , Taiwan
8.
J Hazard Mater ; 172(2-3): 700-6, 2009 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-19665842

RESUMO

In this article, the effects of temperature on the formation of macroporous zinc oxide bundles and its photocatalytic activity under a variety of experimental conditions were reported. Thermal decomposition of zinc oxalate dihydrate yields hexagonal wurtzite-type ZnO bundles. Increased the decomposition temperatures resulted in decreased time required for bundle formation, with a corresponding increase in nanoparticles agglomeration. ZnO bundle formation was facilitated up to 200 degrees C after complete decomposition of zinc oxalate into ZnO at 400 degrees C in 15 min. However, low temperature (such as 100 degrees C) was not facilitated nanobundle formation, suggesting the importance of temperature on ZnO bundles formation. In addition, nitrogen adsorption experiments confirmed the presence of macroporous structure in the bundles. The photocatalytic decolorization and adsorption of methylene blue dye (MB) on ZnO bundles were investigated under UV light irradiation. The adsorption and decolorization efficiency of macroporous bundles were higher than the fused bundles. In conclusion, ZnO bundles are efficient and easily recyclable photocatalyst.


Assuntos
Catálise/efeitos da radiação , Temperatura , Óxido de Zinco/química , Adsorção , Nanopartículas/química , Nitrogênio/química , Processos Fotoquímicos/efeitos dos fármacos , Processos Fotoquímicos/efeitos da radiação , Raios Ultravioleta
9.
Cancer Gene Ther ; 16(11): 820-31, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19373278

RESUMO

In this study, we took advantage of the overexpression of human epidermal growth factor receptor 2 (HER-2) in prostate cancers to design lentiviruses with modified envelope proteins that bind antibodies to specific cell-surface antigens. When bound to trastuzumab (Herceptin, Genentech, CA), lentiviruses were able to selectively infect androgen-sensitive LNCaP and castration-resistant C4-2 human prostate cancer cell lines, both of which express high levels of HER-2. To test for a therapeutic effect, we engineered our antibody-binding lentiviruses to express thymidine kinase, which can convert the non-toxic pro-drug ganciclovir (GCV) into a cytotoxic form. LNCaP and C4-2 cells infected by these viruses were sensitive to GCV killing. In vivo, C4-2 xenograft tumors treated either intratumorally or i.v. with trastuzumab-bound lentivirus expressed luciferase, although the latter route was less tumor specific. When a prostate-specific promoter for governing luciferase expression was combined with trastuzumab-mediated delivery, there was a further enrichment in targeting viral gene expression in prostate tumors. In conclusion, we found that although prostate cancers that express high levels of HER-2 are resistant to the killing effects of trastuzumab, they can be targeted for selective gene expression and destruction by viruses with envelope proteins engineered to bind this antibody.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Lentivirus/química , Neoplasias da Próstata/tratamento farmacológico , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais Humanizados , Antineoplásicos/química , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/metabolismo , Vetores Genéticos/química , Vetores Genéticos/genética , Vetores Genéticos/fisiologia , Humanos , Imuno-Histoquímica , Lentivirus/genética , Lentivirus/fisiologia , Masculino , Camundongos , Camundongos Nus , Receptor ErbB-2/metabolismo , Trastuzumab , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Eur J Clin Microbiol Infect Dis ; 28(8): 1013-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19280234

RESUMO

A nationwide susceptibility surveillance of Streptococcus pneumoniae and Haemophilus influenzae isolates collected from patients treated at the intensive care units (ICUs) of ten Taiwanese major teaching hospitals was conducted from September 2005 through November 2005. High rates of resistance (intermediate/resistant) of S. pneumoniae to penicillin (85% resistance), ceftriaxone (46%/20%), and cefepime (43%/15%) by meningitis criteria, and in contrast, non-susceptibilities (intermediate/resistant) to penicillin (0%/0%), ceftriaxone (20%/0%) and cefepime (15%/0%) by non-meningitis criteria were noted (p values < 0.05) by the Clinical and Laboratory Standards Institute 2008. Resistant rate of S. pneumoniae to azithromycin was also high (63%). S. pneumoniae isolates were significantly more susceptible to ertapenem (87%) than to imipenem (39%) and meropenem (44%) (p values < 0.05). Rates of non-susceptibilities of H. influenzae isolates to ampicillin and cefaclor were high (55% and 45%, respectively). No beta-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae isolates were found. Imipenem has a notably higher MIC(90) value (8 microg/ml) for H. influenzae than that of the other two carbapenems. Tigecycline showed good in vitro activities against these two respiratory pathogens. High rates of resistance among isolates of S. pneumoniae and H. influenzae continue to exist in the ICUs of Taiwan.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/efeitos dos fármacos , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Haemophilus influenzae/isolamento & purificação , Hospitais de Ensino , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Streptococcus pneumoniae/isolamento & purificação , Taiwan
11.
Eur J Clin Microbiol Infect Dis ; 28(2): 215-20, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18716805

RESUMO

To determine the antimicrobial resistance profiles among clinical isolates of Enterobacteriaceae in Taiwanese intensive care units (ICUs), a national surveillance of antibiotic resistance among important Enterobacteriaceae was conducted from September 2005 through November 2005 at the ICUs of ten major teaching hospitals in Taiwan. A total of 574 Enterobacteriaceae isolates recovered from various clinical samples of our ICU patients were submitted for in vitro test. Minimum inhibitory concentrations (MICs) of these isolates to 18 antimicrobial agents were determined by the broth microdilution method. The prevalences of Enterobacteriaceae isolates with phenotypic extended-spectrum beta-lactamase (ESBL) production were 26% in Klebsiella pneumoniae, 16% in Serratia marcescens, 14% in Escherichia coli, and 13% in Proteus mirabilis, in which a significantly rising prevalence of ESBL production among K. pneumoniae was noted (p = 0.002) when compared with a previous Taiwanese survey in 2000. Heterogeneous resistance to various fluoroquinolones was found among our Enterobacteriaceae isolates, except for Enterobacter cloacae. Emergence of ertapenem-resistant isolates of E. coli, K. pneumoniae, E. cloacae, and S. marcescens was noted. Gradually increasing rates of drug-resistant Enterobacteriaceae were noted in Taiwanese ICUs. Periodic surveillance of the evolutionary trend of antimicrobial resistance among ICU isolates is crucial for starting appropriately empirical antimicrobial therapy in the future.


Assuntos
Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana/genética , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/efeitos dos fármacos , Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana , Taiwan
12.
Hum Exp Toxicol ; 27(5): 417-24, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18715888

RESUMO

The effect of melittin on cytosolic free Ca(2+) concentration ([Ca(2+)](i)) and viability is largely unknown. This study examined whether melittin alters Ca(2+) levels and causes Ca(2+)-dependent cell death in Madin-Darby canine kidney (MDCK) cells. [Ca(2+)](i) and cell death were measured using the fluorescent dyes fura-2 and WST-1 respectively. Melittin at concentrations above 0.5 microM increased [Ca(2+)](i) in a concentration-dependent manner. The Ca(2+) signal was reduced by 75% by removing extracellular Ca(2+). The melittin-induced Ca(2+) influx was also implicated by melittin-caused Mn(2+) influx. After pretreatment with 1 microM thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor), melittin-induced Ca(2+) release was inhibited; and conversely, melittin pretreatment abolished thapsigargin-induced Ca(2+) release. At concentrations of 0.5-20 microM, melittin killed cells in a concentration-dependent manner. The cytotoxic effect of 0.5 microM melittin was nearly completely reversed by prechelating cytosolic Ca(2+) with BAPTA. Melittin at 0.5-2 microM caused apoptosis as assessed by flow cytometry of propidium iodide staining. Collectively, in MDCK cells, melittin induced a [Ca(2+)](i) rise by causing Ca(2+) release from endoplasmic reticulum and Ca(2+) influx from extracellular space. Furthermore, melittin can cause Ca(2+)-dependent cytotoxicity in a concentration-dependent manner.


Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Túbulos Renais/efeitos dos fármacos , Meliteno/toxicidade , Animais , Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quelantes/farmacologia , Cães , Relação Dose-Resposta a Droga , Antagonismo de Drogas , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Fura-2/metabolismo , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Manganês/metabolismo , Meliteno/agonistas , Sais de Tetrazólio/metabolismo , Tapsigargina/farmacologia
13.
J Ethnopharmacol ; 113(2): 210-7, 2007 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-17616290

RESUMO

Salvia miltiorrhiza Bunge (Tanshen), a traditional Chinese herbal medicine, is popularly used to treat cardiovascular disorders. In the present study, effects of tanshinlactone A (C(16)H(12)O(4); M.W. 268), newly discovered from Salvia miltiorrhiza, on phytohemagglutinin (PHA)-stimulated cell proliferation were investigated in human peripheral blood mononuclear cells (PBMC). The results indicated that tanshinlactone A inhibited PBMC proliferation activated with PHA with an IC(50) of 15.6+/-1.9 microM. Cell viability test indicated that inhibitory effects of tanshinlactone A on PBMC proliferation were not through direct cytotoxicity. Furthermore, tanshinlactone A significantly decreased the interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) gene expression in PHA-activated PBMC. It reduced the phosphorylation of mitogen-activated protein kinases (MAPK) involving extracellular signal-regulated protein kinase (ERK), P38, and c-Jun NH(2)-terminal kinase (JNK) in PHA-treated PBMC. We suggested that the inhibitory effects of tanshinlactone A on PHA-induced PBMC proliferation, appeared to be mediated, at least in part, through reduction of MAPK activation and IL-2 and IFN-gamma production. Therefore, data demonstrate for the first time that tanshinlactone A is likely an immunomodulatory agent for PBMC.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Expressão Gênica/efeitos dos fármacos , Interferon gama/genética , Interleucina-2/genética , Salvia miltiorrhiza/química , Acetatos/química , Adulto , Western Blotting , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Hexanos/química , Humanos , Interferon gama/metabolismo , Interleucina-2/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fenantrenos/isolamento & purificação , Fenantrenos/farmacologia , Fito-Hemaglutininas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
14.
Bone ; 40(4): 931-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17236835

RESUMO

The objective of the present study was to assess the ability of bone marrow cells expressing BMP-2 created via lentiviral gene transfer to heal a critical sized femoral defect in a rat model. Femoral defects in Lewis rats were implanted with 5x10(6) rat bone marrow stromal cells (RBMSC) transduced with a lentiviral vector containing either the BMP-2 gene (Group I), the enhanced green fluorescent protein (LV-GFP) gene (Group IV), or RBMSC alone (Group V). We also included femoral defects that were treated with BMP-2-producing RBMSC transduced with lentivirus, 8 weeks after infection (Group III), and a group with 1x10(6) RBMSC transduced with a lentiviral vector with the BMP-2 gene (Group II). All defects (10/10) treated in Group I healed at 8 weeks compared with none of the femora in the control groups (Groups IV and V). In Group II, only one out of 10 femora healed. In Group III, 5 out of 10 femora healed. Significantly higher amounts of in vitro BMP-2 protein production were detected in Groups I, II, and III when compared to that of the control groups (p<0.05). Histomorphometric analysis revealed significantly greater total bone volume in defects in Group I and III when compared to control specimens (p<0.003). Biomechanical testing revealed no significant differences in the healed defects in Groups I and III when compared to intact, nonoperated femora with respect to peak torque and torque to failure. Our results indicate that BMP-2-producing RBMSC created through lentiviral gene transfer have the capability of inducing long-term protein production in vitro and producing substantial new bone formation in vivo.


Assuntos
Proteínas Morfogenéticas Ósseas/genética , Consolidação da Fratura/genética , Técnicas de Transferência de Genes , Fator de Crescimento Transformador beta/genética , Animais , Fenômenos Biomecânicos , Células da Medula Óssea/metabolismo , Transplante de Medula Óssea , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/biossíntese , Feminino , Fêmur/lesões , Fêmur/patologia , Fêmur/fisiologia , Expressão Gênica , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Técnicas In Vitro , Lentivirus/genética , Ratos , Ratos Endogâmicos Lew , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Células Estromais/metabolismo , Células Estromais/transplante , Fator de Crescimento Transformador beta/biossíntese
15.
Hum Exp Toxicol ; 25(8): 461-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16937918

RESUMO

Riluzole is a drug used in the treatment of amyotrophic lateral sclerosis; however, its in vitro action is unclear. In this study, the effect of riluzole on intracellular Ca2+ concentration ([Ca2+]i) in Madin-Darby canine kidney (MDCK) cells was investigated using the Ca2+ -sensitive fluorescent dye, fura-2. Riluzole (100-500 microM) caused a rapid and sustained increase of [Ca2+]i in a concentration-dependent manner (EC50 = 150 microM). Some 40 and 50% of this [Ca2+]i increase was prevented by the removal of extracellular Ca2+ and the addition of La3+, respectively, but was unchanged by dihydropyridines, verapamil and diltiazem. In Ca2+ -free medium, thapsigargin - an inhibitor of the endoplasmic reticulum (ER) Caz+ -ATPase--caused a monophasic [Ca2+]i increase, after which the increasing effect of riluzole on [Ca2+]i was attenuated by 70%; in addition, pre-treatment with riluzole abolished thapsigargin-induced [Ca2+]i increases. U73122, an inhibitor of phospholipase C (PLC), abolished ATP (but not riluzole)-induced [Ca2+]i increases. At concentrations of 250 and 500 microM, riluzole killed 40 and 95% cells, respectively. The cytotoxic effect of riluzole (250 microM) was unaltered by pre-chelating cytosolic Ca2+ with BAPTA. Collectively, in MDCK cells, riluzole rapidly increased [Ca2+]i by stimulating extracellular Ca2+ influx via an La3+ -sensitive pathway and intracellular Ca2+ release from the ER via, as yet, unidentified mechanisms. Furthermore, riluzole caused Ca2+ -unrelated cytotoxicity in a concentration-dependent manner.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Fármacos do Sistema Nervoso Central/farmacologia , Riluzol/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cães , Rim/citologia
16.
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
17.
J Virol ; 79(16): 10210-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16051814

RESUMO

The lack of success of subunit human immunodeficiency virus (HIV) type 1 vaccines to date suggests that multiple components or a complex virion structure may be required. We hypothesized that the failure of current vaccine strategies to induce protective antibodies is linked to the inability of native envelope structures to readily elicit these types of antibodies. We have previously reported on the ability of a formaldehyde-treated, heat-inactivated vaccine to induce modest antibody responses in animal vaccine models. We investigated here whether immunization for HIV with an envelope-modified, formaldehyde-stabilized, heat-inactivated virion vaccine could produce higher-titer and/or broader neutralizing antibody responses. Thus, a clade B vaccine which contains a single point mutation in gp41 (Y706C) that results in increased incorporation of oligomeric Env into virions was constructed. This vaccine was capable of inducing high-titer antibodies that could neutralize heterologous viruses, including those of clades A and C. These results further support the development of HIV vaccines with modifications in native Env structures for the induction of neutralizing antibody responses.


Assuntos
Vacinas contra a AIDS/imunologia , Formaldeído/farmacologia , Anticorpos Anti-HIV/sangue , Proteína gp41 do Envelope de HIV/imunologia , HIV-1/imunologia , Vírion/imunologia , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Coelhos , Vacinação , Vacinas de Produtos Inativados/imunologia
18.
J Virol ; 79(8): 4927-35, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15795278

RESUMO

The lack of success of subunit human immunodeficiency virus type 1 (HIV-1) vaccines to date suggests that multiple components or a complex virion structure may be required. We previously demonstrated retention of the major conformational epitopes of HIV-1 envelope following thermal treatment of virions. Moreover, antibody binding to some of these epitopes was significantly enhanced following thermal treatment. These included the neutralizing epitopes identified by monoclonal antibodies 1b12, 2G12, and 17b, some of which have been postulated to be partially occluded or cryptic in native virions. Based upon this finding, we hypothesized that a killed HIV vaccine could be derived to elicit protective humoral immune responses. Shedding of HIV-1 envelope has been described for some strains of HIV-1 and has been cited as one of the major impediments to developing an inactivated HIV-1 vaccine. In the present study, we demonstrate that treatment of virions with low-dose formaldehyde prior to thermal inactivation retains the association of viral envelope with virions. Moreover, mice and nonhuman primates vaccinated with formaldehyde-treated, thermally inactivated virions produce antibodies capable of neutralizing heterologous strains of HIV in peripheral blood mononuclear cell-, MAGI cell-, and U87-based infectivity assays. These data indicate that it is possible to create an immunogen by using formaldehyde-treated, thermally inactivated HIV-1 virions to induce neutralizing antibodies. These findings have broad implications for vaccine development.


Assuntos
Vacinas contra a AIDS/imunologia , Formação de Anticorpos/imunologia , Linfócitos B/imunologia , HIV-1/imunologia , Vacinas Atenuadas/imunologia , Células Cultivadas , Eletroporação , Formaldeído , Produtos do Gene env/imunologia , Humanos , Eliminação de Partículas Virais/imunologia
20.
Planta Med ; 67(9): 865-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11745027

RESUMO

Two new butanolides, lincomolide A (1), lincomolide B (2), along with seven known compounds, isolinderanolide E, sepesteonol, beta-sitosterol, beta-sitosterol-beta-glucoside, tetradecane, nonanoic acid and decanol, were isolated from the chloroform-soluble portion of the stem bark of Lindera communis. Compound 1 showed cytotoxicity against P-388, KB16 and A549, and 2 exhibited cytotoxicity against P-388 cancer cell lines. Moreover, 1 showed marginal activity against HT-29, and 2 against KB16, A549 and HT-29 cancer cell lines. The structures of these compounds were determined by spectral analyses.


Assuntos
4-Butirolactona/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Lindera , Casca de Planta/química , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Divisão Celular/efeitos dos fármacos , Células HT29/efeitos dos fármacos , Humanos , Células Tumorais Cultivadas
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