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1.
Hematol Oncol ; 42(1): e3240, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38050405

RESUMO

Patients affected by multiple myeloma (MM) have an increased risk of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection and subsequent coronavirus (20)19 disease (COVID-19)-related death. The changing epidemiological and therapeutic scenarios suggest that there has been an improvement in severity and survival of COVID-19 during the different waves of the pandemic in the general population, but this has not been investigated yet in MM patients. Here we analyzed a large cohort of 1221 patients with MM and confirmed SARS-CoV-2 infection observed between February 2020, and August 2022, in the EPICOVIDEHA registry from 132 centers around the world. Median follow-up was 52 days for the entire cohort and 83 days for survivors. Three-hundred and three patients died (24%) and COVID-19 was the primary reason for death of around 89% of them. Overall survival (OS) was significantly higher in vaccinated patients with both stable and active MM versus unvaccinated, while only a trend favoring vaccinated patients was observed in subjects with responsive MM. Vaccinated patients with at least 2 doses showed a better OS than those with one or no vaccine dose. Overall, according to pandemic waves, mortality rate decreased over time from 34% to 10%. In multivariable analysis, age, renal failure, active disease, hospital, and intensive care unit admission, were independently associated with a higher number of deaths, while a neutrophil count above 0.5 × 109 /L was found to be protective. This data suggests that MM patients remain at risk of SARS-CoV-2 infection even in the vaccination era, but their clinical outcome, in terms of OS, has progressively improved throughout the different viral phases of the pandemic.


Assuntos
COVID-19 , Mieloma Múltiplo , Humanos , SARS-CoV-2 , Pandemias , Mieloma Múltiplo/terapia , Sistema de Registros
2.
Haematologica ; 108(1): 22-33, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35545919

RESUMO

Patients with acute myeloid leukemia (AML) are at high risk of dying from coronavirus disease 2019 (COVID-19). The optimal management of AML patients with COVID-19 has not been established. Our multicenter study included 388 adult AML patients diagnosed with COVID-19 between February 2020 and October 2021. The vast majority were receiving or had received AML treatment in the preceding 3 months. COVID-19 was severe in 41.2% and critical in 21.1% of cases. The chemotherapeutic schedule was modified in 174 patients (44.8%), delayed in 68 and permanently discontinued in 106. After a median follow-up of 325 days, 180 patients (46.4%) had died; death was attributed to COVID-19 (43.3%), AML (26.1%) or to a combination of both (26.7%), whereas in 3.9% of cases the reason was unknown. Active disease, older age, and treatment discontinuation were associated with death, whereas AML treatment delay was protective. Seventy-nine patients had a simultaneous AML and COVID-19 diagnosis, with better survival when AML treatment could be delayed (80%; P<0.001). Overall survival in patients with a diagnosis of COVID-19 between January 2020 and August 2020 was significantly lower than that in patients diagnosed between September 2020 and February 2021 and between March 2021 and September 2021 (39.8% vs. 60% vs. 61.9%, respectively; P=0.006). COVID-19 in AML patients was associated with a high mortality rate and modifications of therapeutic algorithms. The best approach to improve survival was to delay AML treatment, whenever possible.


Assuntos
COVID-19 , Hematologia , Leucemia Mieloide Aguda , Humanos , Adulto , Seguimentos , Teste para COVID-19 , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/tratamento farmacológico
3.
Br J Clin Pharmacol ; 89(4): 1452-1461, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36422512

RESUMO

AIM: The objective of this study was to evaluate off-label high-dose ceftazidime population pharmacokinetics in cancer patients with suspected or proven extensively drug-resistant (XDR) Pseudomonas aeruginosa infections and then to compare the achievement of the pharmacokinetic/pharmacodynamic (PK/PD) target after standard and off-label high-dose regimens using population model-based simulations. A further aim was to clinically observe the occurrence of adverse effects during the off-label high-dose ceftazidime treatment. METHODS: In patients treated with off-label high-dose ceftazidime (3 g every 6 h), blood samples were collected and ceftazidime serum levels measured using LC-MS/MS. A pharmacokinetic population model was developed using a nonlinear mixed-effects modelling approach and Monte Carlo simulations were then used to compare standard and high-dose regimens for PK/PD target attainment. RESULTS: A total of 14 cancer patients with serious infection suspected of XDR P. aeruginosa aetiology were eligible for PK analysis. XDR P. aeruginosa was confirmed in 10 patients as the causative pathogen. Population ceftazidime volume of distribution was 13.23 L, while clearance started at the baseline of 1.48 L/h and increased by 0.0076 L/h with each 1 mL/min/1.73 m2 of eGFR. High-dose regimen showed significantly higher probability of target attainment (i.e., 86% vs. 56% at MIC of 32 mg/L). This was translated into a very low mortality rate of 20%. Only one case of reversible neurological impairment was observed. CONCLUSION: We proved the superiority of the ceftazidime off-label high-dose regimen in PK/PD target attainment with very low occurrence of adverse effects. The off-label high-dose regimen should be used to optimize treatment of XDR P. aeruginosa infections.


Assuntos
Neoplasias , Infecções por Pseudomonas , Humanos , Ceftazidima/efeitos adversos , Ceftazidima/farmacocinética , Infecções por Pseudomonas/tratamento farmacológico , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Cromatografia Líquida , Uso Off-Label , Pseudomonas aeruginosa , Espectrometria de Massas em Tandem , Método de Monte Carlo , Testes de Sensibilidade Microbiana , Neoplasias/complicações , Neoplasias/tratamento farmacológico
4.
Hematol Oncol ; 40(2): 280-286, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35120267

RESUMO

COVID-19 significantly impairs survival rates among hematological patients when compared to the general population. Our prospective multicentre project analyzed early administration of anti-SARS-CoV-2 spike protein neutralizing monoclonal antibodies (NmAbs) - bamlanivimab (72%) and casirivimab/imdevimab (28%) - efficacy among hematological patients with early-stage COVID-19. Mortality rate was compared to a control cohort of 575 SARS-CoV-2 positive hematological patients untreated with any specific anti-COVID-19 therapy. 88 hematological patients with lymphomas, acute leukemias, and myeloma as their most frequent underlying diagnoses (72%) were evaluated with a 97 days median follow-up after NmAb administration. One third of patients (32%) were treated with an anti-CD20 monoclonal antibody before COVID-19 diagnosis. Median time between first COVID-19 symptom and NmAb administration was 2 days. When administering NmAb, 29%, 57%, 11%, 2%, and 1% of our patients had asymptomatic, mild, moderate, severe, and critical degrees of COVID-19, respectively. 80% of baseline asymptomatic patients remained asymptomatic following NmAb administration. Median duration of COVID-19 symptoms after NmAb administration was 2.5 days. Progression to severe/critical COVID-19 occurred among a total of 17% (15/88) of our cases and numerically higher with bamlanivimab versus casirivimab/imdevimab (21% vs. 8%; p = 0.215), and myelomas (29%), lymphomas (17%) and acute leukemias (18%), respectively. During final follow-up, nine deaths (10%) were recorded - all after bamlanivimab (p = 0.056) with 8% attributed to COVID-19. Regarding "remdesivir/convalescent plasma naïve" patients, COVID-19 mortality rates were significantly lower in our NmAbs treated cohort compared to the control cohort of untreated SARS-CoV-2 positive hematological patients (6% vs. 16%, p = 0.020), respectively. Our study validated the safety and efficacy of NmAbs early use among hematological patients with newly diagnosed early-stage COVID-19 in terms of alleviating infection course and decreasing mortality. Results confirmed a more positive effect of a casirivimab/imdevimab combination versus bamlanivimab monotherapy.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , SARS-CoV-2 , Anticorpos Monoclonais Humanizados , Anticorpos Neutralizantes , COVID-19/terapia , Teste para COVID-19 , República Tcheca , Humanos , Imunização Passiva , Estudos Prospectivos , Soroterapia para COVID-19
5.
Mediterr J Hematol Infect Dis ; 15(1): e2023001, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36660352

RESUMO

Background: P. aeruginosa sepsis in immunocompromised patients is a serious complication of cancer treatment, especially in the case of an Extensively Drug Resistant (XDR) pathogen. The aim of the study is to evaluate the efficacy of high-dose ceftazidime in the treatment of XDR P. aeruginosa infection and to compare it with the conventionally treated cohort in hemato-oncological patients. Methods: We identified 27 patients with XDR P. aeruginosa infection during the 2008-2018 period, 16 patients served as a conventionally treated cohort with an antipseudomonal beta-lactam antibiotic in standard dose (cohort A), and 11 patients were treated with high-dose ceftazidime (cohort B). Most of the patients were neutropenic and under active treatment for their cancer in both cohorts. Results: Mortality and related mortality were statistically significantly better for cohort B than cohort A; it was 18.2% and 9.1% for cohort B and 68.8% and 68.8% for cohort A, respectively. More patients in cohort A needed mechanical ventilation and renal replacement therapy, 75% and 50% for cohort A and 27.3% and 9.9% for cohort B, respectively. It corresponded well with the worst sequential organ failure score (SOFA) in cohort A compared to cohort B, 16 versus 7, respectively. Reversible neurotoxicity was seen only in two patients in cohort B. Conclusion: Ceftazidime in high doses is a very potent antibiotic (ATB) for treating XDR P. aeruginosa infections in neutropenic cancer with acceptable toxicity.

6.
Biomed Pharmacother ; 150: 112962, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35462331

RESUMO

Low curability of patients diagnosed with acute myeloid leukemia (AML) must be seen as a call for better understanding the disease's mechanisms and improving the treatment strategy. Therapeutic outcome of the crucial anthracycline-based induction therapy often can be compromised by a resistant phenotype associated with overexpression of ABCB1 transporters. Here, we evaluated clinical relevance of ABCB1 in a context of the FMS-like tyrosine kinase 3 (FLT3) inhibitor midostaurin in a set of 28 primary AML samples. ABCB1 gene expression was absolutely quantified, confirming its association with CD34 positivity, adverse cytogenetic risk, and unachieved complete remission (CR). Midostaurin, identified as an ABCB1 inhibitor, increased anthracycline accumulation in peripheral blood mononuclear cells (PBMC) of CD34+ AML patients and those not achieving CR. This effect was independent of FLT3 mutation, indicating even FLT3- AML patients might benefit from midostaurin therapy. In line with these data, midostaurin potentiated proapoptotic processes in ABCB1-overexpressing leukemic cells when combined with anthracyclines. Furthermore, we report a direct linkage of miR-9 to ABCB1 efflux activity in the PBMC and propose miR-9 as a useful prognostic marker in AML. Overall, we highlight the therapeutic value of midostaurin as more than just a FLT3 inhibitor, suggesting its maximal therapeutic outcomes might be very sensitive to proper timing and well-optimized dosage schemes based upon patient's characteristics, such as CD34 positivity and ABCB1 activity. Moreover, we suggest miR-9 as a predictive ABCB1-related biomarker that could be immensely helpful in identifying ABCB1-resistant AML phenotype to enable optimized therapeutic regimen and improved treatment outcome.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP , Leucemia Mieloide Aguda , MicroRNAs , Estaurosporina , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Antraciclinas/farmacologia , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Mutação , Inibidores de Proteínas Quinases/farmacologia , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia
7.
J Assist Reprod Genet ; 28(10): 939-50, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21822582

RESUMO

PURPOSE: The aim of this study was to develop and optimize a strategy for long-term cultivation of luteinizing human granulosa cells (GCs). METHODS: GCs were cultivated in DMEM/F12 medium supplemented with 2% fetal calf serum. In vitro proliferation of GCs was supported by follicular fluid as well as FSH and growth factors. RESULTS: The cultured GCs were maintained for 45 days with a doubling time of 159 ± 24 h. GCs initiated by the addition of follicular fluid and cultivated under low serum conditions reached 10 ± 0.7 population doublings. GCs maintain the typical phenotypic expression and the telomere length according to specific culture conditions. CONCLUSION: Our present study has demonstrated that GCs can be maintained in vitro for at least 45 days and this cell model can be beneficial when studying hormonal regulation associated with follicular maturation and preparation of oocytes for fertilization.


Assuntos
Proliferação de Células , Células da Granulosa/citologia , Fenótipo , Técnicas de Cultura de Células , Células Cultivadas , Feminino , Citometria de Fluxo , Líquido Folicular , Humanos , Cariotipagem , Telômero , Fatores de Tempo
8.
J Hematol Oncol ; 14(1): 168, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34649563

RESUMO

BACKGROUND: Patients with hematological malignancies (HM) are at high risk of mortality from SARS-CoV-2 disease 2019 (COVID-19). A better understanding of risk factors for adverse outcomes may improve clinical management in these patients. We therefore studied baseline characteristics of HM patients developing COVID-19 and analyzed predictors of mortality. METHODS: The survey was supported by the Scientific Working Group Infection in Hematology of the European Hematology Association (EHA). Eligible for the analysis were adult patients with HM and laboratory-confirmed COVID-19 observed between March and December 2020. RESULTS: The study sample includes 3801 cases, represented by lymphoproliferative (mainly non-Hodgkin lymphoma n = 1084, myeloma n = 684 and chronic lymphoid leukemia n = 474) and myeloproliferative malignancies (mainly acute myeloid leukemia n = 497 and myelodysplastic syndromes n = 279). Severe/critical COVID-19 was observed in 63.8% of patients (n = 2425). Overall, 2778 (73.1%) of the patients were hospitalized, 689 (18.1%) of whom were admitted to intensive care units (ICUs). Overall, 1185 patients (31.2%) died. The primary cause of death was COVID-19 in 688 patients (58.1%), HM in 173 patients (14.6%), and a combination of both COVID-19 and progressing HM in 155 patients (13.1%). Highest mortality was observed in acute myeloid leukemia (199/497, 40%) and myelodysplastic syndromes (118/279, 42.3%). The mortality rate significantly decreased between the first COVID-19 wave (March-May 2020) and the second wave (October-December 2020) (581/1427, 40.7% vs. 439/1773, 24.8%, p value < 0.0001). In the multivariable analysis, age, active malignancy, chronic cardiac disease, liver disease, renal impairment, smoking history, and ICU stay correlated with mortality. Acute myeloid leukemia was a higher mortality risk than lymphoproliferative diseases. CONCLUSIONS: This survey confirms that COVID-19 patients with HM are at high risk of lethal complications. However, improved COVID-19 prevention has reduced mortality despite an increase in the number of reported cases.


Assuntos
COVID-19/complicações , Neoplasias Hematológicas/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/terapia , Europa (Continente)/epidemiologia , Feminino , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/terapia , Hospitalização , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores de Risco , SARS-CoV-2/isolamento & purificação , Adulto Jovem
9.
J Biomed Biotechnol ; 2010: 673513, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20976265

RESUMO

We provide a detailed characteristic of stem cells isolated and expanded from the human dental pulp. Dental pulp stem cells express mesenchymal cell markers STRO-1, vimentin, CD29, CD44, CD73, CD90, CD166, and stem cell markers Sox2, nestin, and nucleostemin. They are multipotent as shown by their osteogenic and chondrogenic potential. We measured relative telomere length in 11 dental pulp stem cell lines at different passages by quantitative real-time PCR. Despite their large proliferative capacity, stable viability, phenotype, and genotype over prolonged cultivation, human dental pulp stem cells suffer from progressive telomere shortening over time they replicate in vitro. Relative telomere length (T/S) was inversely correlated with cumulative doubling time. Our findings indicate that excessive ex vivo expansion of adult stem cells should be reduced at minimum to avoid detrimental effects on telomere maintenance and measurement of telomere length should become a standard when certificating the status and replicative age of stem cells prior therapeutic applications.


Assuntos
Polpa Dentária/citologia , Células-Tronco/citologia , Telômero/patologia , Adolescente , Adulto , Antígenos CD/metabolismo , Contagem de Células , Proliferação de Células , Células Cultivadas , Condrogênese , Ensaio de Unidades Formadoras de Colônias , DNA , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Cinética , Masculino , Microscopia de Contraste de Fase , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/metabolismo , Osteogênese , Padrões de Referência , Células-Tronco/metabolismo , Fatores de Tempo , Adulto Jovem
10.
Acta Medica (Hradec Kralove) ; 53(2): 93-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20672745

RESUMO

AIMS: Our aims were to isolate stem cells from human exfoliated deciduous teeth (SHED), to cultivate them in vitro and to investigate their basic biological properties, phenotype and to compare our findings with dental pulp stem cells (DPSC) isolated from permanent teeth. METHODS: Dental pulp was gently evacuated from exfoliated teeth. After enzymatic dissociation of dental pulp, SHED were cultivated in modified cultivation media for mesenchymal adult progenitor cells containing 2% FCS and supplemented with growth factors and insulin, transferrin, sodium (ITS) supplement. Cell viability and other biological properties were examined using a Vi-Cell analyzer and a Z2-Counter. DNA analyses and phenotyping were performed with flow cytometry. RESULTS: We were able to cultivate SHED over 45 population doublings. Our results showed that SHED cultivated under same conditions as DPSC had longer average population doubling time (41.3 hrs for SHED vs. 24.5 hrs for DPSC). Phenotypic comparison of cultivated SHED to that of cultivated DPSC showed differential expression CD29, CD44, CD71, CD117, CD 166. During long-term cultivation, SHED did not showed any signs of degeneration or spontaneous differentiation. CONCLUSIONS: We isolated stem cells from exfoliated teeth. In comparison to DPSC, SHED proliferation rate was about 50% slower, and SHED showed slightly different phenotype. These cells may be extremely useful for stem cell tissue banking, further stem cell research and future therapeutic applications.


Assuntos
Diferenciação Celular , Polpa Dentária/citologia , Células-Tronco/citologia , Dente Decíduo/citologia , Adulto , Antígenos CD/análise , Proliferação de Células , Células Cultivadas , Criança , Humanos , Dente Serotino/citologia , Células-Tronco/imunologia , Esfoliação de Dente
11.
Cancers (Basel) ; 12(6)2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32560251

RESUMO

Pharmacotherapy of acute myeloid leukemia (AML) remains challenging, and the disease has one of the lowest curability rates among hematological malignancies. The therapy outcomes are often compromised by the existence of a resistant AML phenotype associated with overexpression of ABCB1 and ABCG2 transporters. Because AML induction therapy frequently consists of anthracycline-like drugs, their efficiency may also be diminished by drug biotransformation via carbonyl reducing enzymes (CRE). In this study, we investigated the modulatory potential of the CDK4/6 inhibitors abemaciclib, palbociclib, and ribociclib on AML resistance using peripheral blood mononuclear cells (PBMC) isolated from patients with de novo diagnosed AML. We first confirmed inhibitory effect of the tested drugs on ABCB1 and ABCG2 in ABC transporter-expressing resistant HL-60 cells while also showing the ability to sensitize the cells to cytotoxic drugs even as no effect on AML-relevant CRE isoforms was observed. All tested CDK4/6 inhibitors elevated mitoxantrone accumulations in CD34+ PBMC and enhanced accumulation of mitoxantrone was found with abemaciclib and ribociclib in PBMC of FLT3-ITD- patients. Importantly, the accumulation rate in the presence of CDK4/6 inhibitors positively correlated with ABCB1 expression in CD34+ patients and led to enhanced apoptosis of PBMC in contrast to CD34- samples. In summary, combination therapy involving CDK4/6 inhibitors could favorably target multidrug resistance, especially when personalized based on CD34- and ABCB1-related markers.

12.
Acta Medica (Hradec Kralove) ; 51(3): 165-72, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19271684

RESUMO

The major functions of granulosa cells (GCs) include the production of steroids, as well as a myriad of growth factors to interact with the oocyte during its development within the ovarian follicle. Also FSH stimulates GCs to convert androgens (coming from the thecal cells) to estradiol by aromatase. However, after ovulation the GCs produce progesterone that may maintain a potential pregnancy. Experiments with human GCs are mainly focused on the purification of GCs from ovarian follicular fluid followed by FACS analysis or short-term cultivation. The aim of our study was to cultivate GCs for a long period, to characterize their morphology and phenotype. Moreover, we have cultivated GCs under gonadotropin stimulation in order to simulate different pathological mechanisms during folliculogenesis (e.g. ovarian hyperstimulation syndrome). GCs were harvested from women undergoing in vitro fertilization. Complex oocyte-cumulus oophorus was dissociated by hyaluronidase. The best condition for transport of GCs was optimized as short transport in follicular fluid at 37 degrees C. GCs expansion medium consisted of DMEM/F12, 2% FCS, ascorbic acid, dexamethasone, L-glutamine, gentamycine, penicillin, streptomycin and growth factors (EGF, bFGF). GCs transported in follicular fluid and cultivated in 2% FCS containing DMEM/F12 medium supplemented with follicular fluid presented increased adhesion, proliferation, viability and decreased doubling time. Cell viability was 92% and mean cell doubling time was 52 hrs. We have optimized transport and cultivation protocols for long-term cultivation of GCs.


Assuntos
Técnicas de Cultura de Células , Células da Granulosa/citologia , Adulto , Meios de Cultura , Feminino , Humanos
13.
Int J Radiat Biol ; 88(5): 393-404, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22348537

RESUMO

PURPOSE: Mesenchymal stem cells isolated from bone marrow (BM-MSC) and periodontal ligament (PLSC) are cells with high proliferative potential and ability to self-renewal. Characterization of these cells under genotoxic stress conditions contributes to the assessment of their prospective usage. The aim of our study was to evaluate changes in BM-MSC and PLSC caused by ionizing radiation. METHODS: Human BM-MSC and PLSC were irradiated with the doses up to 20 Gy by Co(60) and observed 13 days; viability, proliferation, apoptosis and senescence induction, and changes in expression and phosphorylation status of related proteins were studied. RESULTS: Irradiation with the doses up to 20 Gy significantly reduces proliferation, but has no significant effect on cell viability. The activation of tumor suppressor protein 53 (p53) and its phosphorylations on serines 15 and 392 were detected from the first day after irradiation by 20 Gy and remained elevated to day 13. Expression of cyclin-dependent kinases inhibitor 1A (p21(Cip1/Waf1)) increased. The cell cycle was arrested in G2 phase. Instead of apoptosis we have detected hallmarks of stress-induced premature senescence: increase in cyclin-dependent kinases inhibitor 2A (p16(INK4a)) and increased activity of senescence-associated ß-galactosidase. CONCLUSION: Mesenchymal stem cells isolated from bone marrow and periodontal ligament respond to ionizing radiation by induction of stress-induced premature senescence without apparent differences in their radiation response.


Assuntos
Células-Tronco Adultas/citologia , Células-Tronco Adultas/efeitos da radiação , Células da Medula Óssea/citologia , Senescência Celular/efeitos da radiação , Raios gama/efeitos adversos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos da radiação , Ligamento Periodontal/citologia , Células-Tronco Adultas/metabolismo , Apoptose/efeitos da radiação , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Ativação Enzimática/efeitos da radiação , Feminino , Regulação da Expressão Gênica/efeitos da radiação , Histonas/metabolismo , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Fosforilação/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo
14.
Stem Cells Dev ; 19(12): 1855-62, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20331357

RESUMO

Adult human dental pulp contains stem cells (DPSCs) that are capable of differentiation into osteoblasts, odontoblasts, adipocytes, and neuronal-like cells. Because these cells have potential use in tissue regeneration, herein we characterized the response of DPSC lines to ionizing radiation (IR). These DPSC lines have been developed from the extracted molars of healthy donors. DPSCs were cultivated in a unique media supplemented with epidermal growth factor (EGF) and platelet-derived growth factor (PDGF). Since tissue homeostasis depends on a precise balance among cell proliferation, senescence, and cell death, we explored the effects of IR (2-20 Gy) on the proliferative activity of DPSCs and the molecular pathways involved. Even the highest dose used (20 Gy) did not induce DPSC apoptosis. After irradiation with doses of 6 and 20 Gy, DPSCs accumulated in the G2 phase of the cell cycle. DPSCs responded to IR (20 Gy) with senescence detected as SA-ß-galactosidase positivity, beginning on the third day after irradiation. Twenty-four hours after irradiation, p53 and its serine 15 and 392 phosphorylated forms were detected. At this time, p21 (WAF1) was induced. Increases in protein p16 were observed from the third day following irradiation and continued till the end of the examination (Day 13). We conclude that DPSCs respond to IR-induced damage by permanent cell cycle arrest in the G2 phase and by stress-induced premature senescence.


Assuntos
Ciclo Celular/efeitos da radiação , Senescência Celular/efeitos da radiação , Polpa Dentária/citologia , Radiação Ionizante , Células-Tronco/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo , Adulto , Apoptose/efeitos da radiação , Western Blotting , Sobrevivência Celular , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Polpa Dentária/efeitos da radiação , Fator de Crescimento Epidérmico/farmacologia , Humanos , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/citologia , beta-Galactosidase/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-19365523

RESUMO

AIMS: Our aims were to isolate dental pulp stem cells, to cultivate them in various media and to investigate their basic biological properties and phenotype. METHODS: 16 lines of dental pulp stem cells (DPSCs) were isolated from an impacted third molar. After enzymatic dissociation of dental pulp, DPSCs were cultivated in modified cultivation media for mesenchymal adult progenitor cells containing 2 % or 10 % fetal calf serum (FCS), or in modified 2 % FCS cultivation media supplemented with ITS. Cell viability and other biological properties were examined periodically using a Vi-Cell analyzer and Z2-Counter. DNA analysis and phenotyping were done using flow cytometry. RESULTS: We were able to cultivate DPSCs in all tested cultivation media over 40 population doublings. Our results showed that DPSCs cultivated in medium supplemented with ITS had shorter average population doubling time (24.5, 15.55-35.12 hours) than DPSCs cultivated in 2 % FCS (55.43, 21.57-187.14 hours) or 10 % FCS (42.56, 11.86 - 101.3 hours). Cell diameter was not affected and varied from 15 to 16 microm. DPSCs viability in the 9(th) passage was over 90 %. Our phenotypical analysis was highly positivity for CD29, CD44, CD90 and HLA I, and negative for CD34, CD45, CD71, HLA II. DPSC lines cultivated in all media showed no signs of degeneration or spontaneous differentiation during the expansion process. CONCLUSIONS: We showed that ITS supplement in the cultivation media greatly increased the proliferative activity of DPSCs. Other DPSC biological properties and phenotype were not affected.


Assuntos
Polpa Dentária/citologia , Células-Tronco/citologia , Adulto , Antígenos CD/análise , Proliferação de Células , Células Cultivadas , Meios de Cultura , Polpa Dentária/imunologia , Feminino , Humanos , Masculino , Fenótipo , Células-Tronco/imunologia , Adulto Jovem
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