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1.
Infant Behav Dev ; 69: 101778, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36240549

RESUMO

This study examined the use of various communicative intentions (CIs) of mothers directed to their children in two contexts: playtime and mealtime at two linguistic stages: preverbal and single-word. The study revealed that statements were most prevalent during mealtime, while both statements and directives were prevalent during playtime. Particularly, directives were more frequent during playtime than during mealtime. Moreover, the number of CIs directed to children in the preverbal stage was higher than children in the single-word stage. These findings emphasize the role of context and culture on the mother-child language use in general and CIs in particular.


Assuntos
Relações Mãe-Filho , Mães , Feminino , Criança , Humanos , Intenção , Linguagem Infantil , Refeições
2.
Cell Death Dis ; 12(3): 268, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712556

RESUMO

Targeting cell division by chemotherapy is a highly effective strategy to treat a wide range of cancers. However, there are limitations of many standard-of-care chemotherapies: undesirable drug toxicity, side-effects, resistance and high cost. New small molecules which kill a wide range of cancer subtypes, with good therapeutic window in vivo, have the potential to complement the current arsenal of anti-cancer agents and deliver improved safety profiles for cancer patients. We describe results with a new anti-cancer small molecule, WEHI-7326, which causes cell cycle arrest in G2/M, cell death in vitro, and displays efficacious anti-tumor activity in vivo. WEHI-7326 induces cell death in a broad range of cancer cell lines, including taxane-resistant cells, and inhibits growth of human colon, brain, lung, prostate and breast tumors in mice xenografts. Importantly, the compound elicits tumor responses as a single agent in patient-derived xenografts of clinically aggressive, treatment-refractory neuroblastoma, breast, lung and ovarian cancer. In combination with standard-of-care, WEHI-7326 induces a remarkable complete response in a mouse model of high-risk neuroblastoma. WEHI-7326 is mechanistically distinct from known microtubule-targeting agents and blocks cells early in mitosis to inhibit cell division, ultimately leading to apoptotic cell death. The compound is simple to produce and possesses favorable pharmacokinetic and toxicity profiles in rodents. It represents a novel class of anti-cancer therapeutics with excellent potential for further development due to the ease of synthesis, simple formulation, moderate side effects and potent in vivo activity. WEHI-7326 has the potential to complement current frontline anti-cancer drugs and to overcome drug resistance in a wide range of cancers.


Assuntos
Antimitóticos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Animais , Antimitóticos/farmacocinética , Antimitóticos/toxicidade , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Mitose/efeitos dos fármacos , Neoplasias/patologia , Células PC-3 , Ratos Sprague-Dawley , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Br J Cancer ; 122(3): 434-444, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31806880

RESUMO

BACKGROUND: Stathmin mediates cell migration and invasion in vitro, and metastasis in vivo. To investigate stathmin's role on the metastatic process, we performed integrated mRNA-miRNA expression analysis to identify pathways regulated by stathmin. METHODS: MiRNA and gene arrays followed by miRNA-target-gene integration were performed on stathmin-depleted neuroblastoma cells (CtrlshRNA vs. Stmn Seq2shRNA). The expression of the predicted target PTPN14 was evaluated by RT-qPCR, western blot and immunohistochemistry. Gene-silencing technology was used to assess the role of PTPN14 on proliferation, migration, invasion and signalling pathway. RESULTS: Stathmin levels modulated the expression of genes and miRNA in neuroblastoma cells, leading to a deregulation of migration and invasion pathways. Consistent with gene array data, PTPN14 mRNA and protein expression were downregulated in stathmin- depleted neuroblastoma cells and xenografts. In two independent neuroblastoma cells, suppression of PTPN14 expression led to an increase in cell migration and invasion. PTPN14 and stathmin expression did not act in a feedback regulatory loop in PTPN14- depleted cells, suggesting a complex interplay of signalling pathways. The effect of PTPN14 on YAP pathway activation was cell-type dependent. CONCLUSIONS: Our findings demonstrate that stathmin levels can regulate PTPN14 expression, which can modulate neuroblastoma cell migration and invasion.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neuroblastoma/genética , Proteínas Tirosina Fosfatases não Receptoras/genética , Estatmina/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Camundongos , Camundongos SCID , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Transplante de Neoplasias , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais , Estatmina/metabolismo
4.
Eur J Clin Microbiol Infect Dis ; 35(10): 1649-54, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27325440

RESUMO

Beta-hemolytic group G streptococci (GGS) are increasingly recognized as a source of substantial morbidity, causing mild to severe sporadic infections as well as outbreaks. The purpose of this study was to determine the genetic diversity and antibiotic resistance of GGS in Israel in order to aid in prevention and control. A total of 325 GGS isolates were collected in Israel between 2007 and 2011 from three determined settings: (1) carriage (n = 60), an observational longitudinal carriage study in the IF, (2) non-invasive (n = 166), clinical sporadic and epidemic non-invasive cases in the IDF, and (3) invasive (n = 99) cases of bacteremia collected during this period in Israel from a similar age group, at the national Streptococcal Reference Center. All isolates were characterized genetically and by their antibiotic-resistance profile. emm typing revealed 35 distinct types and subtypes among 228 S. dysgalactiae subsp. equisimilis (SDSE) isolates, with high genetic diversity. An additional 97 GGS were identified as Streptococcus anginosus (SAG). The proportion of SDSE was higher in the invasive (100 %) and non-invasive (63.8 %) isolates compared to the carriage ones (38.3 %). Clindamycin, erythromycin, azithromycin and tetracycline resistance was detected in 6.6 %, 8.6 %, 9.7 % and 37.6 % of isolates, respectively. Overall, the most resistant isolates were in the invasive group and the fewest were in the SAG group. Considerable genetic diversity and common antibiotic resistance were revealed among GGS strains which differed according to the epidemiologic settings. Further clinical, epidemiological and basic research of GGS as a pathogen is warranted.


Assuntos
Bacteriemia/microbiologia , Portador Sadio/microbiologia , Farmacorresistência Bacteriana , Variação Genética , Infecções Estreptocócicas/microbiologia , Streptococcus/classificação , Streptococcus/efeitos dos fármacos , Adolescente , Adulto , Antibacterianos/farmacologia , Genótipo , Humanos , Israel , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Streptococcus/genética , Streptococcus/isolamento & purificação , Adulto Jovem
5.
Cell Cycle ; 14(24): 3908-19, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26697841

RESUMO

Reorganization of the actin cytoskeleton during mitosis is crucial for regulating cell division. A functional role for γ-actin in mitotic arrest induced by the microtubule-targeted agent, paclitaxel, has recently been demonstrated. We hypothesized that γ-actin plays a role in mitosis. Herein, we investigated the effect of γ-actin in mitosis and demonstrated that γ-actin is important in the distribution of ß-actin and formation of actin-rich retraction fibers during mitosis. The reduced ability of paclitaxel to induce mitotic arrest as a result of γ-actin depletion was replicated with a range of mitotic inhibitors, suggesting that γ-actin loss reduces the ability of broad classes of anti-mitotic agents to induce mitotic arrest. In addition, partial depletion of γ-actin enhanced centrosome amplification in cancer cells and caused a significant delay in prometaphase/metaphase. This prolonged prometaphase/metaphase arrest was due to mitotic defects such as uncongressed and missegregated chromosomes, and correlated with an increased presence of mitotic spindle abnormalities in the γ-actin depleted cells. Collectively, these results demonstrate a previously unknown role for γ-actin in regulating centrosome function, chromosome alignment and maintenance of mitotic spindle integrity.


Assuntos
Centrossomo/metabolismo , Mitose/fisiologia , Ciclo Celular/genética , Humanos , Células MCF-7 , Metáfase/genética , Metáfase/fisiologia , Microscopia de Fluorescência , Microtúbulos/metabolismo , Mitose/genética , RNA Interferente Pequeno/genética , Fuso Acromático/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
6.
Mol Oncol ; 9(7): 1484-500, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25963741

RESUMO

Retinoids are an important component of neuroblastoma therapy at the stage of minimal residual disease, yet 40-50% of patients treated with 13-cis-retinoic acid (13-cis-RA) still relapse, indicating the need for more effective retinoid therapy. Vorinostat, or Suberoylanilide hydroxamic acid (SAHA), is a potent inhibitor of histone deacetylase (HDAC) classes I & II and has antitumor activity in vitro and in vivo. Fenretinide (4-HPR) is a synthetic retinoid which acts on cancer cells through both nuclear retinoid receptor and non-receptor mechanisms. In this study, we found that the combination of 4-HPR + SAHA exhibited potent cytotoxic effects on neuroblastoma cells, much more effective than 13-cis-RA + SAHA. The 4-HPR + SAHA combination induced caspase-dependent apoptosis through activation of caspase 3, reduced colony formation and cell migration in vitro, and tumorigenicity in vivo. The 4-HPR and SAHA combination significantly increased mRNA expression of thymosin-beta-4 (Tß4) and decreased mRNA expression of retinoic acid receptor α (RARα). Importantly, the up-regulation of Tß4 and down-regulation of RARα were both necessary for the 4-HPR + SAHA cytotoxic effect on neuroblastoma cells. Moreover, Tß4 knockdown in neuroblastoma cells increased cell migration and blocked the effect of 4-HPR + SAHA on cell migration and focal adhesion formation. In primary human neuroblastoma tumor tissues, low expression of Tß4 was associated with metastatic disease and predicted poor patient prognosis. Our findings demonstrate that Tß4 is a novel therapeutic target in neuroblastoma, and that 4-HPR + SAHA is a potential therapy for the disease.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neuroblastoma/tratamento farmacológico , Timosina/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Fenretinida/administração & dosagem , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Timosina/genética , Vorinostat
7.
Prev Med ; 65: 141-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24905864

RESUMO

INTRODUCTION: Preventing smoking initiation will protect future generations from smoking-attributable death and disease. This study examines the correlates and patterns of initiation among Israeli youth using time-to-event analysis and other methods. METHODS: Twenty-four consecutive representative samples (1986-2009) of new military recruits (N=50,254) were analyzed. Cox regression and Kaplan-Meier analysis were used to identify factors associated with smoking initiation, and logistic regression was used to identify factors associated with smoking status. RESULTS: The most hazardous age for smoking initiation was seventeen, subsequent to the mean age of smoking initiation (males: 15.7, females: 16.0). Age of initiation and age of greatest hazard for initiation declined among recruits between the years 1986 and 2009. Earlier smoking initiation among boys and girls was significantly associated with low education levels (<12years) (males: HR=2.98, CI: [2.79, 3.18]; females: HR=3.35, CI: [2.96, 3.80]), low paternal education levels, Russian birthplace, and religion. Earlier initiation in boys was associated with high fitness levels and low/medium socio-economic status. Earlier initiation in girls was associated with being Western-born and ever-use of contraception. CONCLUSIONS: Smoking initiation among Israeli youth recruited to the armed forces is associated with individual and family characteristics, particularly low education levels. Time-to-event analysis complements traditional means of understanding smoking initiation by identifying ages at which initiation hazard is high.


Assuntos
Comportamento do Adolescente , Militares/estatística & dados numéricos , Fumar/epidemiologia , Adolescente , Comportamento do Adolescente/etnologia , Idade de Início , Escolaridade , Feminino , Humanos , Israel/epidemiologia , Estimativa de Kaplan-Meier , Masculino , Prevalência , Modelos de Riscos Proporcionais , Fatores de Risco , Distribuição por Sexo , Fumar/etnologia , Prevenção do Hábito de Fumar
8.
Cytoskeleton (Hoboken) ; 70(3): 148-60, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23335583

RESUMO

Actin and microtubule interactions are important for many cellular events, however these interactions are poorly described. Alterations in γ-actin are associated with diseases such as hearing loss and cancer. Functional investigations demonstrated that partial depletion of γ-actin affects cell polarity and induces resistance to microtubule-targeted agents. To determine whether γ-actin alterations directly affect microtubule dynamics, microtubule dynamic instability was analyzed in living cells following partial siRNA depletion of γ-actin. Partial depletion of γ-actin suppresses interphase microtubule dynamics by 17.5% due to a decrease in microtubule shortening rates and an increase in microtubule attenuation. γ-Actin partial depletion also increased distance-based microtubule catastrophe and rescue frequencies. In addition, knockdown of γ-actin delayed mitotic progression, partially blocking metaphase-anaphase transition and inhibiting cell proliferation. Interestingly, in the presence of paclitaxel, interphase microtubule dynamics were further suppressed by 24.4% in the γ-actin knockdown cells, which is comparable to 28.8% suppression observed in the control siRNA treated cells. Paclitaxel blocked metaphase-anaphase transition in both the γ-actin knockdown cells and the control siRNA cells. However, the extent of mitotic arrest was much higher in the control cells (28.4%), compared to the γ-actin depleted cells (8.5%). Therefore, suppression of microtubule dynamics by partial depletion of γ-actin is associated with marked delays in metaphase-anaphase transition and not mitotic arrest. This is the first demonstration that γ-actin can modulate microtubule dynamics by reducing the microtubule shortening rate, promoting paused/attenuated microtubules, and increasing transition frequencies suggesting a mechanistic link between γ-actin and microtubules.


Assuntos
Actinas/metabolismo , Microtúbulos/metabolismo , Actinas/genética , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Microscopia de Fluorescência , Microtúbulos/efeitos dos fármacos , Mitose/efeitos dos fármacos , Paclitaxel/farmacologia
9.
PLoS One ; 7(2): e30734, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22359551

RESUMO

Aurora kinase inhibitors are new mitosis-targeting drugs currently in clinical trials for the treatment of haematological and solid malignancies. However, knowledge of the molecular factors that influence sensitivity and resistance remains limited. Herein, we developed and characterised an in vitro leukaemia model of resistance to the Aurora B inhibitor ZM447439. Human T-cell acute lymphoblastic leukaemia cells, CCRF-CEM, were selected for resistance in 4 µM ZM447439. CEM/AKB4 cells showed no cross-resistance to tubulin-targeted and DNA-damaging agents, but were hypersensitive to an Aurora kinase A inhibitor. Sequencing revealed a mutation in the Aurora B kinase domain corresponding to a G160E amino acid substitution. Molecular modelling of drug binding in Aurora B containing this mutation suggested that resistance is mediated by the glutamate substitution preventing formation of an active drug-binding motif. Progression of resistance in the more highly selected CEM/AKB8 and CEM/AKB16 cells, derived sequentially from CEM/AKB4 in 8 and 16 µM ZM447439 respectively, was mediated by additional defects. These defects were independent of Aurora B and multi-drug resistance pathways and are associated with reduced apoptosis mostly likely due to reduced inhibition of the catalytic activity of aurora kinase B in the presence of drug. Our findings are important in the context of the use of these new targeted agents in treatment regimes against leukaemia and suggest resistance to therapy may arise through multiple independent mechanisms.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Leucemia de Células T/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Apoptose , Aurora Quinase A , Aurora Quinase B , Aurora Quinases , Benzamidas/farmacologia , Sítios de Ligação/genética , Domínio Catalítico/genética , Linhagem Celular Tumoral , Humanos , Leucemia de Células T/genética , Mutação de Sentido Incorreto , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Quinazolinas/farmacologia
10.
Eur Psychiatry ; 27(8): 612-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21565466

RESUMO

BACKGROUND: Schizophrenia and bipolar disorder are associated with impairments in insight, leading to a poorer clinical outcome and functioning. Earlier studies comparing the two disorders on the basis of insight included inpatients or patients who were clinically symptomatic. The current study therefore assessed patients in remission of affective symptoms and positive symptoms of schizophrenia. METHODS: Schizophrenia and bipolar disorder patients (n=32, n=34; respectively) underwent clinical and functional evaluations. Insight was assessed using the Scale to assess Unawareness of Mental Disorder (SUMD) and the positive and negative syndrome scale (PANSS). Attention was assessed using a continuous performance task (CANTAB's rapid visual information processing). RESULTS: Schizophrenia patients displayed poorer insight into having a mental disorder and into the social consequences thereof compared to the bipolar disorder patients. They were also less aware of their anhedonia-asociality. Age, however, was significantly correlated with insight and differences in insight between the patient groups became nonsignificant when age was used as a covariate in the statistical analyses. Age was not a moderating variable of the relationship between diagnosis and insight. CONCLUSIONS: Significant differences in insight held by the two patient groups might be related to age disparities between patient groups. Earlier studies did not adequately address these age differences, their cause and their potential effects on findings. These issues are explored with regard to the findings of the current study, as well as earlier studies, emphasizing the need for further research of the relationship between age and insight.


Assuntos
Sintomas Afetivos/fisiopatologia , Atenção/fisiologia , Conscientização/fisiologia , Transtorno Bipolar/fisiopatologia , Esquizofrenia/fisiopatologia , Adolescente , Adulto , Sintomas Afetivos/diagnóstico , Transtorno Bipolar/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adulto Jovem
11.
Epidemiol Infect ; 140(3): 561-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21676361

RESUMO

Of 742 army recruits tested for pneumococcal nasopharyngeal/oropharyngeal carriage, 6·6% were positive. Frequent sharing of a drinking glass/bottle was a common, strong and independent risk factor for pneumococcal carriage. Our findings strongly suggest, for the first time, that in young adults, transmission of pneumococci may occur via saliva and this should be considered when conducting an outbreak investigation and carriage studies.


Assuntos
Portador Sadio/transmissão , Transmissão de Doença Infecciosa , Infecções Pneumocócicas/transmissão , Saliva/microbiologia , Streptococcus pneumoniae/isolamento & purificação , Adolescente , Adulto , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Estudos Transversais , Humanos , Masculino , Militares , Nasofaringe/microbiologia , Orofaringe/microbiologia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Adulto Jovem
12.
FASEB J ; 25(12): 4423-33, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21908715

RESUMO

Cell migration plays a crucial role in numerous cellular functions, and alterations in the regulation of cell migration are required for invasive transformation of a tumor cell. While the mechanistic process of actin-based migration has been well documented, little is known as to the specific function of the nonmuscle actin isoforms in mammalian cells. Here, we present a comprehensive examination of γ-actin's role in cell migration using an RNAi approach. The partial suppression of γ-actin expression in SH-EP neuroblastoma cells resulted in a significant decrease in wound healing and transwell migration. Similarly, the knockdown of γ-actin significantly reduced speed of motility and severely affected the cell's ability to explore, which was, in part, due to a loss of cell polarity. Moreover, there was a significant increase in the size and number of paxillin-containing focal adhesions, coupled with a significant decrease in phosphorylated paxillin in γ-actin-knockdown cells. In addition, there was a significant increase in the phosphorylation of cofilin and myosin regulatory light chain, suggesting an overactivated Rho-associated kinase (ROCK) signaling pathway in γ-actin-knockdown cells. The alterations in the phosphorylation of paxillin and myosin regulatory light chain were unique to γ-actin and not ß-actin knockdown. Inhibition of the ROCK pathway with the inhibitor Y-27632 restored the ability of γ-actin-knockdown cells to migrate. This study demonstrates γ-actin as a potential upstream regulator of ROCK mediated cell migration.


Assuntos
Actinas/metabolismo , Movimento Celular/fisiologia , Quinases Associadas a rho/metabolismo , Actinas/antagonistas & inibidores , Actinas/genética , Amidas/farmacologia , Sequência de Bases , Linhagem Celular , Polaridade Celular/fisiologia , Adesões Focais/fisiologia , Técnicas de Silenciamento de Genes , Humanos , Modelos Biológicos , Cadeias Leves de Miosina/metabolismo , Paxilina/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética , Transdução de Sinais , Cicatrização/fisiologia
13.
Mol Cancer Ther ; 9(5): 1339-48, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20442307

RESUMO

Overexpression of betaIII-tubulin is associated with resistance to tubulin-binding agents (TBA) in a range of tumor types. We previously showed that small interfering RNA silencing of betaIII-tubulin expression hypersensitized non-small cell lung cancer cells to TBAs. To determine whether betaIII-tubulin mediates its effect on drug-induced mitotic arrest and cell death by differentially regulating microtubule behavior, the effects of betaIII-tubulin knockdown on microtubule dynamics were analyzed in H460 non-small cell lung cancer cells stably expressing green fluorescent protein-betaI-tubulin. Interphase cells were examined at three vincristine and paclitaxel concentrations that (a) inhibited cell proliferation, (b) induced 5% to 10% mitotic arrest, and (c) induced 30% to 40% mitotic arrest. In the absence of either drug, betaIII-tubulin knockdown caused no significant change in microtubule dynamic instability. At 2 nmol/L vincristine (IC(50)), overall microtubule dynamicity was significantly suppressed in betaIII-tubulin knockdowns (-31.2%) compared with controls (-6.5%). Similar results were obtained with paclitaxel, suggesting that knockdown of betaIII-tubulin induces hypersensitivity by enhancing stabilization of microtubule dynamics at low drug concentrations. At higher drug concentrations (> or =40 nmol/L vincristine; > or =20 nmol/L paclitaxel), betaIII-tubulin knockdown resulted in significantly reduced suppressive effects on microtubule dynamicity with little or no further increase in mitotic arrest, compared with control cells. Importantly, apoptosis was markedly increased by betaIII-tubulin knockdown independent of further suppression of microtubule dynamics and mitotic arrest. These results show that betaIII-tubulin knockdown enhances the effectiveness of TBAs through two mechanisms: suppression of microtubule dynamics at low drug concentrations and a mitosis-independent mechanism of cell death at higher drug concentrations.


Assuntos
Apoptose , Microtúbulos/metabolismo , Mitose/fisiologia , Multimerização Proteica , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/fisiologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Carcinoma/tratamento farmacológico , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/patologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , Avaliação Pré-Clínica de Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Cinética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Mitose/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , RNA Interferente Pequeno/farmacologia , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/uso terapêutico , Células Tumorais Cultivadas
14.
J Natl Cancer Inst ; 98(19): 1363-74, 2006 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-17018783

RESUMO

BACKGROUND: Proteomic investigations have revealed alterations in cytoskeletal proteins expressed in human acute lymphoblastic leukemia cells that are resistant to microtubule-disrupting agents. We characterized gamma-actin expression in antimicrotubule drug-resistant leukemia and examined the effect of altered gamma-actin in resistance of acute lymphoblastic leukemia to antimicrotubule agents. METHODS: Two-dimensional polyacrylamide gel electrophoresis and mass spectrometry were used to identify actin proteins in human acute lymphoblastic leukemia cell lines resistant to vinblastine (CCRF-CEM/VLB100 cells) and desoxyepothilone B (CCRF-CEM/dEpoB140 cells). Fluorescence-based cycle sequencing was used to detect gene mutations. Site-directed mutagenesis was used to generate mutant gamma-actin expression plasmids, which were used to transfect mouse NIH/3T3 cells. Clonogenic analysis was used for drug sensitivity studies. A small interfering RNA (siRNA) was used to block gamma-actin gene expression in human neuroblastoma SH-EP cells. Expression of gamma-actin (normalized to that of beta2-microglobulin [beta2M]) in primary leukemia cells obtained from patients at diagnosis (n = 44) and relapse (n = 25) was examined using semiquantitative reverse transcription-polymerase chain reaction. Statistical significance of changes in the ratio of gamma-actin to beta2M expression between diagnosis and relapse samples was determined by two-sided unpaired Student's t tests. RESULTS: We identified novel mutant forms of gamma-actin and the concomitant loss of wild-type gamma-actin in CCRF-CEM/VLB100 cells and CCRF-CEM/dEpoB140 cells. Mouse NIH/3T3 cells that expressed the mutant gamma-actin proteins were more resistant to antimicrotubule agents than cells transfected with empty plasmid. Human neuroblastoma SH-EP cells transfected with gamma-actin siRNA displayed higher relative resistance to paclitaxel (P<.001), vinblastine (P = .04), and epothilone B (P = .045) than mock-transfected cells. No gamma-actin gene mutations were identified in 37 samples of primary leukemia cells (eight from patients at diagnosis, 29 from patients at relapse). Gamma-actin gene expression was lower in acute lymphoblastic leukemia samples collected at clinical relapse (n = 25; mean gamma-actin/beta2M = 0.53) than in samples collected at diagnosis (n = 44; mean gamma-actin/beta2M = 0.68; difference = 0.15, 95% confidence interval [CI] = 0.04 to 0.27, P = .01). CONCLUSIONS: These data provide functional and associative clinical evidence of a novel form of drug resistance that involves interactions between gamma-actin and microtubules.


Assuntos
Actinas/efeitos dos fármacos , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Microtúbulos/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/efeitos dos fármacos , Actinas/genética , Actinas/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Criança , Análise Mutacional de DNA , Eletroforese em Gel Bidimensional , Epotilonas/farmacologia , Técnica Indireta de Fluorescência para Anticorpo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Humanos , Leucina , Espectrometria de Massas , Camundongos , Microtúbulos/genética , Microtúbulos/metabolismo , Mutação/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Plasmídeos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Prolina , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Ensaio Tumoral de Célula-Tronco , Valina , Vimblastina/farmacologia
15.
Isr Med Assoc J ; 3(10): 731-3, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11692546

RESUMO

BACKGROUND: The exact value of follow-up ultrasonography and computed tomography in the non-operative management of blunt splenic injuries is not yet defined. Although follow-up studies have been recommended to detect possible complications of the initial injury, evidence shows that routine follow-up CT scans usually do not affect management of these patients. OBJECTIVE: To determine whether follow-up imaging influences the management of patients with blunt splenic injury. METHODS: Between 1995 and 1999, 155 trauma patients were admitted with splenic trauma to a major trauma center. Excluded from the study were trauma patients with penetrating injuries, children, and those who underwent immediate laparotomy due to hemodynamic instability or associated injuries. The remaining trauma patients were managed conservatively. Splenic injury was suspected by focused abdominal sonography for trauma, upon admission, and confirmed by CT scan. The severity of splenic injury was graded from I to V. The clinical outcome was obtained from medical records. RESULTS: We identified 32 adult patients (27 males and 5 females) with blunt splenic injuries who were managed non-operatively. In two patients it was not successful, and splenectomy was performed because of hemodynamic deterioration. The remaining 30 stable patients were divided into two groups: those who had only the initial ultrasound and CT scan with no follow-up studies (n = 8), and those who underwent repeat follow-up ultrasound or CT scan studies (n = 22). The severity of injury was similar in both groups in the second group follow-up studies showed normal spleens in 2 patients, improvement in 11, no change in 8, and deterioration in one. All patients in both groups were managed successfully with good clinical outcome. CONCLUSION: In the present series the follow-up radiological studies did not affect patient management. Follow-up imaging can be omitted in clinically stable patients with blunt splenic trauma grade I-III.


Assuntos
Baço/lesões , Ferimentos não Penetrantes/diagnóstico por imagem , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Baço/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ultrassonografia , Ferimentos não Penetrantes/classificação , Ferimentos não Penetrantes/terapia
16.
Eur J Clin Microbiol Infect Dis ; 20(2): 123-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11305466

RESUMO

Epidemiological and clinical features of shigellosis occurring among cohorts of Israeli recruits followed-up for 3-6 months during the summer field training of years 1993-1997 were studied. The incidence rate of culture-proven shigellosis was the highest (78 cases per 1,000 recruits) in 1996 and the lowest (13 cases per 1,000 recruits) in 1995. Shigella sonnei (152 isolates) and Shigella flexneri (151 isolates) were the most common species. Fifty percent of the patients with shigellosis had fever (>37.5 degrees C), compared to only 18% of the subjects with other diarrheal diseases (P < 0.001). The duration of illness was longer among subjects with shigellosis than among those with other diarrheal diseases (P < 0.001). Illness due to Shigella flexneri was more severe than illness caused by Shigella sonnei.


Assuntos
Disenteria Bacilar/epidemiologia , Militares , Shigella flexneri/isolamento & purificação , Shigella sonnei/isolamento & purificação , Adolescente , Adulto , Estudos de Coortes , Diarreia/epidemiologia , Diarreia/microbiologia , Disenteria Bacilar/imunologia , Disenteria Bacilar/prevenção & controle , Humanos , Incidência , Israel/epidemiologia , Masculino , Estudos Prospectivos , Vacinas contra Shigella/uso terapêutico , Shigella flexneri/imunologia , Shigella sonnei/imunologia
17.
Am J Epidemiol ; 153(2): 194-201, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11159166

RESUMO

An enzyme-linked immunosorbent assay system using oocyst lysate as antigen was used to detect serum- specific antibody responses to Cryptosporidium parvum between 1989 and 1994 in consecutive sera obtained at birth, and at the age of 6, 12, and 23 months, from 52 infants living in a Bedouin town located in the south of Israel. The serologic tests revealed high levels of immunoglobulin G anti-Cryptosporidium at birth that dropped significantly by the age of 6 months and then rose continuously to a geometric mean titer of 481 at age 23 months. The serum immunoglobulin M Cryptosporidium antibodies rose continuously from nearly undetectable levels at birth to a geometric mean titer of 471 (157-fold increase) at age 23 months. All the subjects already showed at 6 months a significant rise in immunoglobulin M. A significant rise in immunoglobulin A titers was detected in 48% and 91% of subjects at 6 and 23 months, respectively. By monthly surveillance, microscopy using the modified Ziehl-Neelsen method and confirmed by indirect immunofluorescence assay detected Cryptosporidium antigens in only 11% at age 6 months and 48% at age 23 months. The extent of exposure to Cryptosporidium immediately after birth as detected by serology is much higher than that predicted by frequent prospective assessment of stool samples.


Assuntos
Anticorpos Antiprotozoários/sangue , Árabes/estatística & dados numéricos , Criptosporidiose/diagnóstico , Cryptosporidium parvum/imunologia , Fezes/parasitologia , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Adulto , Distribuição por Idade , Animais , Criptosporidiose/sangue , Criptosporidiose/etnologia , Criptosporidiose/imunologia , Criptosporidiose/parasitologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Seguimentos , Humanos , Lactente , Recém-Nascido , Israel/epidemiologia , Masculino , Morbidade , Sensibilidade e Especificidade
18.
Infect Immun ; 68(8): 4492-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10899847

RESUMO

Enterotoxigenic Escherichia coli (ETEC) is one of the leading causes of diarrhea among Israeli soldiers serving in field units. Two double-blind placebo-controlled, randomized trials were performed among 155 healthy volunteers to evaluate the safety and immunogenicity of different lots of the oral, killed ETEC vaccine consisting of two doses of whole cells plus recombinantly produced cholera toxin B subunit (rCTB). The two doses of vaccine lot E005 and the first dose of vaccine lot E003 were well tolerated by the volunteers. However, 5 (17%) vaccinees reported an episode of vomiting a few hours after the second dose of lot E003; none of the placebo recipients reported similar symptoms. Both lots of vaccine stimulated a rate of significant antibody-secreting cell (ASC) response to CTB and to colonization factor antigen I (CFA/I) after one or two doses, ranging from 85 to 100% and from 81 to 100%, respectively. The rate of ASC response to CS2, CS4, and CS5 was slightly lower than the rate of ASC response induced to CTB, CFA/I, and CS1. The second vaccine dose enhanced the response to CTB but did not increase the frequencies or magnitude of ASC responses to the other antigens. The two lots of the ETEC vaccine induced similar rates of serum antibody responses to CTB and CFA/I which were less frequent than the ASC responses to the same antigens. Based on these safety and immunogenicity data, an efficacy study of the ETEC vaccine is under way in the Israel Defense Force.


Assuntos
Proteínas de Bactérias/uso terapêutico , Vacinas Bacterianas/uso terapêutico , Diarreia/prevenção & controle , Infecções por Escherichia coli/prevenção & controle , Proteínas de Fímbrias , Administração Oral , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/efeitos adversos , Vacinas Bacterianas/imunologia , Toxina da Cólera/imunologia , Método Duplo-Cego , Vacinas contra Escherichia coli , Feminino , Humanos , Israel , Masculino , Militares , Placebos
19.
Isr J Med Sci ; 17(9-10): 810-5, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7309465

RESUMO

Breast cancer is the most common malignant disease in women in Israel. Approximately 1,000 new cases are diagnosed yearly. The peak incidence in all the population groups and periods observed is after the menopause. A steady increase in female breast cancer indicence was observed over a 17-yr period. The greatest increase occurred in the low-incidence group of Jews born in Asia/Africa.


Assuntos
Neoplasias da Mama/epidemiologia , Etnicidade , Judeus , Adolescente , Adulto , África/etnologia , Fatores Etários , Idoso , Ásia/etnologia , Feminino , Humanos , Israel , Pessoa de Meia-Idade , Fatores de Tempo
20.
México; Tiacuilo de los Hnos; 1974. 163 p.
Monografia em Espanhol | HomeoIndex - Homeopatia | ID: hom-8386
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