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1.
HIV Med ; 19 Suppl 1: 66-70, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29488703

RESUMO

OBJECTIVES: To describe the characteristics of clients who enrolled into of an opt-in, HIV, HBV & HCV Voluntary Counseling and Testing Program in Dobrogea Region, Romania (VCT) and to identify the utility of the pre-test counseling sessions in increasing subjective perception regarding transmission knowledge for the clients attending the VCT program. METHODS: Cross sectional data collection, between August 2015 and September 2016. Sociodemographic and behavioral information were collected for the clients who enrolled at two Baylor centers. Counselors were trained regarding the delivery of standardized information during the session, to reduce variation. After the pre-test session clients evaluated the subjective level of knowledge (SK) increase regarding viral transmission. RESULTS: 3065 clients were screened at the two centers and completed the SK increase assessment after the pre-test session. About 9% of all persons tested had reactive results to any of the infections in the context of high exposure risks for 62% and low hepatitis B vaccination rates (8%). 78% of attendees perceived that their knowledge regarding HIV and viral hepatitis transmission increasing with more than 60% as the result of the pretest counselling; more information was gained about hepatitis transmission compared with HIV. CONCLUSION: Cumulative prevalence in Dobrogea community is high. The NGO-run VCT program is helping the healthcare system to efficiently screen for undiagnosed HIV and hepatitis cases. Pre-test counselling is directly contributing to increasing SK among attendees. Routine HIV and hepatitis integrated pre-test counseling should be considered as a good-practice even in settings where it is not compulsory by law.


Assuntos
Aconselhamento/métodos , Transmissão de Doença Infecciosa/prevenção & controle , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Hepatite B/prevenção & controle , Hepatite C/prevenção & controle , Adolescente , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Infecções por HIV/psicologia , Pesquisa sobre Serviços de Saúde , Hepatite B/psicologia , Hepatite C/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Romênia , Inquéritos e Questionários , Adulto Jovem
2.
J Periodontal Res ; 53(5): 657-681, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29882313

RESUMO

The purpose of this systematic review and meta-analysis was to assess the prevalence, incidence and risk factors of peri-implantitis in the current literature. An electronic search was performed to identify publications from January 1980 until March 2016 on 9 databases. The prevalence and incidence of peri-implantitis were assessed in different subgroups of patients and the prevalences were adjusted for sample size (SSA) of studies. For 12 of 111 identified putative risk factors and risk indicators, forest plots were created. Heterogeneity analysis and random effect meta-analysis were performed for selected potential risk factors of peri-implantitis. The search retrieved 8357 potentially relevant studies. Fifty-seven studies were included in the systematic review. Overall, the prevalence of peri-implantitis on implant level ranged from 1.1% to 85.0% and the incidence from 0.4% within 3 years, to 43.9% within 5 years, respectively. The median prevalence of peri-implantitis was 9.0% (SSA 10.9%) for regular participants of a prophylaxis program, 18.8% (SSA 8.8%) for patients without regular preventive maintenance, 11.0% (SSA 7.4%) for non-smokers, 7.0% (SSA 7.0%) among patients representing the general population, 9.6% (SSA 9.6%) for patients provided with fixed partial dentures, 14.3% (SSA 9.8%) for subjects with a history of periodontitis, 26.0% (SSA 28.8%) for patients with implant function time ≥5 years and 21.2% (SSA 38.4%) for ≥10 years. On a medium and medium-high level of evidence, smoking (effect summary OR 1.7, 95% CI 1.25-2.3), diabetes mellitus (effect summary OR 2.5; 95% CI 1.4-4.5), lack of prophylaxis and history or presence of periodontitis were identified as risk factors of peri-implantitis. There is medium-high evidence that patient's age (effect summary OR 1.0, 95% CI 0.87-1.16), gender and maxillary implants are not related to peri-implantitis. Currently, there is no convincing or low evidence available that identifies osteoporosis, absence of keratinized mucosa, implant surface characteristics or edentulism as risk factors for peri-implantitis. Based on the data analyzed in this systematic review, insufficient high-quality evidence is available to the research question. Future studies of prospective, randomized and controlled type including sufficient sample sizes are needed. The application of consistent diagnostic criteria (eg, according to the latest definition by the European Workshop on Periodontology) is particularly important. Very few studies evaluated the incidence of peri-implantitis; however, this study design may contribute to examine further the potential risk factors.


Assuntos
Peri-Implantite/epidemiologia , Peri-Implantite/etiologia , Humanos , Incidência , Prevalência , Fatores de Risco
3.
Mol Hum Reprod ; 23(8): 535-548, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28586423

RESUMO

STUDY QUESTION: How does the human oocyte transcriptome change with age and ovarian reserve? SUMMARY ANSWER: Specific sets of human oocyte messenger RNAs (mRNAs) and non-coding RNAs (ncRNAs) are affected independently by age and ovarian reserve. WHAT IS KNOWN ALREADY: Although it is well established that the ovarian reserve diminishes with increasing age, and that a woman's age is correlated with lower oocyte quality, the interplay of a diminished reserve and age on oocyte developmental competence is not clear. After maturation, oocytes are mostly transcriptionally quiescent, and developmental competence prior to embryonic genome activationrelies on maternal RNA and proteins. STUDY DESIGN, SIZE, DURATION: A total of 36 vitrified/warmed MII oocytes from 30 women undergoing oocyte donation were included in this study, processed and analyzed individually. PARTICIPANTS/MATERIALS, SETTING, METHODS: Total RNA from each oocyte was independently isolated, amplified, labeled, and hybridized on HTA 2.0 arrays (Affymetrix). Data were analyzed using TAC software, in four groups, each including nine oocytes, according to the woman's age and antral follicular count (AFC) (mean ± SD): Young with High AFC (YH; age 21 ± 1 years and 24 ± 3 follicles); Old with High AFC (OH; age 32 ± 2 years and 29 ± 7 follicles); Young with Low AFC (YL; age 24 ± 2 years and 8 ± 2 follicles); Old with Low AFC (OL; age 34 ± 1 years and 7 ± 1 follicles). qPCR was performed to validate arrays. MAIN RESULTS AND THE ROLE OF CHANCE: We identified a set of 30 differentially expressed mRNAs when comparing oocytes from women with different ages and AFC. In addition, 168 non-coding RNAs (ncRNAs) were differentially expressed in relation to age and/or AFC. Few mRNAs have been identified as differentially expressed transcripts, and among ncRNAs, a set of Piwi-interacting RNAs clusters (piRNAs-c) and precursor microRNAs (pre-miRNAs) were identified as increased in high AFC and old groups, respectively. Our results indicate that age and ovarian reserve are associated with specific ncRNA profiles, suggesting that oocyte quality might be mediated by ncRNA pathways. LARGE SCALE DATA: Data can be found via GEO accession number GSE87201. LIMITATIONS, REASONS FOR CAUTION: The oldest woman included in the study was 35 years old, thus our results cannot readily be extrapolated to women older than 35 or infertile women. WIDER IMPLICATIONS OF THE FINDINGS: We show, for the first time, that several non-coding RNAs, usually regulating DNA transcription, are differentially expressed in relation to age and/or ovarian reserve. Interestingly, the mRNA transcriptome of in vivo matured oocytes remains remarkably stable across ages and ovarian reserve, suggesting the possibility that changes in the non-coding transcriptome might regulate some post-transcriptional/translational mechanisms which might, in turn, affect oocyte developmental competence. STUDY FUNDING AND COMPETING INTEREST(S): This work was supported by intramural funding of Clinica EUGIN and by the Secretary for Universities and Research of the Ministry of Economy and Knowledge of the Government of Catalonia. J.H. and A.S. are employees of Affymetrix, otherwise there are no competing interests.


Assuntos
Envelhecimento/fisiologia , Oócitos/metabolismo , Folículo Ovariano/citologia , Transcriptoma , Adulto , Separação Celular , Feminino , Humanos , Oogênese , Controle de Qualidade , RNA/metabolismo , Adulto Jovem
4.
BMC Public Health ; 15: 798, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26285702

RESUMO

BACKGROUND: Timing of childhood vaccinations has received close attention in many countries. Little is known about the trends in correctly timed vaccination in former Soviet countries. We examined trends in vaccination coverage and correct timing of vaccination in two post-Soviet countries, Armenia and Kyrgyzstan, and analyzed factors associated with delayed vaccinations. METHODS: We used data from the Demographic and Health Surveys; the surveys were conducted in 2000 (n = 1726), 2005 (n = 1430) and 2010 (n = 1473) in Armenia and in 1997 (n = 1127) and 2012 (n = 4363) in Kyrgyzstan. We applied the Kaplan-Meier method to estimate age-specific vaccination coverage with diphtheria, tetanus and pertussis (DTP) vaccine and a measles-containing vaccine (MCV). A Cox proportional hazard regression with shared frailty was used to examine factors associated with delayed vaccinations. RESULTS: Vaccination coverage for all three doses of the DTP vaccine increased in Armenia from 92 % in 2000 to 96 % in 2010. In Kyrgyzstan, DTP coverage was 96 % and 97 % in 1997 and 2012, respectively. Vaccination coverage for MCV increased from 89 % (Armenia, 2000) and 93 % (Kyrgyzstan, 1997) to 97 % (Armenia, 2010) and 98 % (Kyrgyzstan, 2012). The proportion of children with correctly timed vaccinations increased over time for all examined vaccinations in both countries. For example, the proportion of children in Armenia with correctly timed first DTP dose (DTP1) increased from 46 % (2000) to 66 % (2010). In Kyrgyzstan, the proportion of correctly timed DTP1 increased from 75 % (1997) to 87 % (2012). In Armenia, delays in the third DTP dose (DTP3) and MCV vaccinations were less likely to occur in the capital, whereas in Kyrgyzstan DTP3 and MCV start was delayed in the capital compared to other regions of the country. Also, in Armenia living in urban areas was associated with delayed vaccinations. CONCLUSIONS: Vaccination coverage and timing of vaccination improved over the last years in both countries. Further efforts are needed to reduce regional differences in timely vaccinations.


Assuntos
Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Programas de Imunização/organização & administração , Esquemas de Imunização , Vacinação em Massa/organização & administração , Vacina contra Sarampo/administração & dosagem , Adolescente , Armênia/epidemiologia , Criança , Proteção da Criança/estatística & dados numéricos , Pré-Escolar , Feminino , Humanos , Lactente , Quirguistão/epidemiologia , Masculino
5.
J Exp Med ; 181(6): 2141-51, 1995 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-7760003

RESUMO

The mechanisms that regulate the commitment of a totipotent stem cell to the megakaryocytic lineage are largely unknown. Using a molecular approach to the study of megakaryocytopoiesis and platelet production, mice in which thrombocytopoiesis could be controlled were produced by targeting the expression of the herpes simplex virus thymidine kinase toxigene to megakaryocytes using the regulatory region of the gene encoding the alpha subunit of the platelet integrin alpha IIb beta 3. The programmed eradication of the megakaryocytic lineage was induced by treating transgenic mice bearing the hybrid construct (alpha IIbtk) with the antiherpetic drug ganciclovir (GCV). After 10 d of treatment, the platelet number was reduced by > 94.6%. After discontinuing GCV, the bone marrow was repopulated with megakaryocytes and the platelet count was restored within 7 d. Prolonged GCV treatment induced erythropenia in the transgenic mice. Assays of myeloid progenitor cells in vitro demonstrated that the transgene was expressed in early erythro-megakaryocytic progenitor cells. The reversibility and facility of this system provides a powerful model to determine both the critical events in megakaryocytic and erythroid lineage development and for evaluating the precise role that platelets play in the pathogenesis of a number of vascular occlusive disorders.


Assuntos
Eritrócitos/citologia , Hematopoese/fisiologia , Megacariócitos/citologia , Glicoproteínas da Membrana de Plaquetas/genética , Regiões Promotoras Genéticas , Trombocitopenia/fisiopatologia , Timidina Quinase/genética , Animais , Sequência de Bases , Medula Óssea/patologia , Células da Medula Óssea , Ensaio de Unidades Formadoras de Colônias , Primers do DNA , Hematopoese/genética , Herpesvirus Humano 1/enzimologia , Herpesvirus Humano 1/genética , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Glicoproteínas da Membrana de Plaquetas/biossíntese , Reação em Cadeia da Polimerase , Proteínas Recombinantes/biossíntese , Trombocitopenia/sangue , Timidina Quinase/biossíntese , Transfecção
6.
AJNR Am J Neuroradiol ; 41(5): 938-940, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32354709

RESUMO

CSF-venous fistula is an important treatable cause of spontaneous intracranial hypotension that is often difficult to detect using traditional imaging techniques. Herein, we describe the technical aspects and diagnostic performance of MR myelography when used for identifying CSF-venous fistulas. We report 3 cases in which the CSF-venous fistula was occult on CT myelography but readily detected using MR myelography.


Assuntos
Vazamento de Líquido Cefalorraquidiano/diagnóstico por imagem , Fístula/diagnóstico por imagem , Hipotensão Intracraniana/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Mielografia/métodos , Adulto , Meios de Contraste , Feminino , Fístula/complicações , Gadolínio , Humanos , Hipotensão Intracraniana/etiologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Veias/diagnóstico por imagem
7.
Science ; 246(4936): 1498-501, 1989 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17756007

RESUMO

Detection of very intense short radio bursts from Neptune was possible as early as 30 days before closest approach and at least 22 days after closest approach. The bursts lay at frequencies in the range 100 to 1300 kilohertz, were narrowband and strongly polarized, and presumably originated in southern polar regions ofthe planet. Episodes of smooth emissions in the frequency range from 20 to 865 kilohertz were detected during an interval of at least 10 days around closest approach. The bursts and the smooth emissions can be described in terms of rotation in a period of 16.11 +/- 0.05 hours. The bursts came at regular intervals throughout the encounter, including episodes both before and after closest approach. The smooth emissions showed a half-cycle phase shift between the five episodes before and after closest approach. This experiment detected the foreshock of Neptune's magnetosphere and the impacts of dust at the times of ring-plane crossings and also near the time of closest approach. Finally, there is no evidence for Neptunian electrostatic discharges.

8.
BMC Pharmacol ; 9: 5, 2009 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-19291310

RESUMO

BACKGROUND: Diclofenac is a nonsteroidal anti-inflammatory drug which is available as prescription (RX) and over-the-counter (OTC) medication for the systemic and topical treatment of painful and inflammatory conditions such as arthritis and back pain. This study was undertaken to investigate the distribution and retention of diclofenac and/or its metabolites in inflamed tissues, using the carrageenan-induced inflammation model and quantitative whole body autoradiography in rats. METHODS: [14C]diclofenac sodium was administrated as a single 2 mg/kg oral dose 1 h after injection of carrageenan into one front and one hind footpads and subcutaneously into the dorsum of the neck of rats. A control animal received saline injections. Three carrageenan-treated rats and one control rat were sacrificed at 1, 4, 8, and 24 h after [14C]diclofenac sodium administration (total of 4 rats/time point). The carcasses were immediately snap-frozen and prepared for cryosectioning. Lengthwise whole-body sections (40 microm thick), including all major tissues, were obtained from different levels across the body. The tissue concentrations of total radiolabeled components were determined using quantitative autoradioluminography. RESULTS: The radioactivity patterns demonstrated that diclofenac and/or its metabolites preferentially distributed into the inflamed tissues. In unharmed tissues the distribution was similar in control and treated animals. The exposure, based on the areas under the tissue concentration versus time (AUC(0-tlast)), was 26 and 53 fold higher in the inflamed neck and inflamed footpads of treated animals than in control rats; the exposures in unharmed tissues were similar in the treated and control rats, and the AUC(0-tlast) was 17 fold higher in the inflamed paws than in the non inflamed footpads of the carrageenan-treated rats. The higher exposure in the inflamed tissues may be explained partly to the fact that the elimination of total radiolabeled components from inflamed tissues (t(1/2) = 6 h) appeared lower than from the corresponding unharmed tissues (t(1/2) = 2 h). CONCLUSION: This animal study demonstrated that diclofenac and/or its metabolites were rapidly and preferentially taken up and retained in inflamed tissues. Although there were theoretical considerations that mildly acidic NSAID may show some preferential distribution in inflamed tissues there was no clear experimental proof for diclofenac until the present study.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Diclofenaco/farmacocinética , Inflamação/tratamento farmacológico , Animais , Autorradiografia , Carragenina , Diclofenaco/administração & dosagem , Inflamação/induzido quimicamente , Masculino , Ratos , Ratos Long-Evans , Fatores de Tempo , Distribuição Tecidual
9.
Science ; 365(6460): 1441-1445, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31604272

RESUMO

Surveys have shown that super-Earth and Neptune-mass exoplanets are more frequent than gas giants around low-mass stars, as predicted by the core accretion theory of planet formation. We report the discovery of a giant planet around the very-low-mass star GJ 3512, as determined by optical and near-infrared radial-velocity observations. The planet has a minimum mass of 0.46 Jupiter masses, very high for such a small host star, and an eccentric 204-day orbit. Dynamical models show that the high eccentricity is most likely due to planet-planet interactions. We use simulations to demonstrate that the GJ 3512 planetary system challenges generally accepted formation theories, and that it puts constraints on the planet accretion and migration rates. Disk instabilities may be more efficient in forming planets than previously thought.

10.
Neuroscience ; 157(1): 29-39, 2008 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-18804150

RESUMO

Recently evidence has accumulated that schizophrenia can arise from primary synaptic defects involving structural proteins particularly, microtubule associated proteins. Previous experiments have demonstrated that a STOP (stable tubule only peptide) gene deletion in mice leads to a phenotype mimicking some aspects of positive symptoms classically observed in schizophrenic patients. In the current study, we determined if STOP null mice demonstrate behavioral abnormalities related to the social and cognitive impairments of schizophrenia. Compared with wild-type mice, STOP null mice exhibited deficits in the non-aggressive component of social recognition, short term working memory and social and spatial learning. As described in humans, learning deficits in STOP null mice were poorly sensitive to long term treatment with typical neuroleptics. Since social and cognitive dysfunction have consistently been considered as central features of schizophrenia, we propose that STOP null mice may provide a useful model to understand the neurobiological correlates of social and cognitive defects in schizophrenia and to develop treatments that better target these symptoms.


Assuntos
Antipsicóticos/farmacologia , Cognição/fisiologia , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/fisiologia , Esquizofrenia/genética , Psicologia do Esquizofrênico , Comportamento Social , Animais , Comportamento Alimentar/fisiologia , Relações Interpessoais , Aprendizagem/fisiologia , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Knockout , Desempenho Psicomotor/fisiologia , Reconhecimento Psicológico/fisiologia , Olfato/fisiologia , Percepção Espacial/fisiologia
11.
Curr Opin Immunol ; 8(6): 822-30, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8994862

RESUMO

The past year has seen significant advances in our understanding of the role of the B7-CD28/CTLA-4 pathway in T cell activation and self-tolerance. Recent studies have demonstrated that CTLA-4 is a critical negative regulator of T cell activation and autoreactivity, revealing a previously unsuspected means by which costimulation is involved in the maintenance and breakdown of self-tolerance. Manipulation of this costimulatory pathway in animal models of autoimmunity has shown an important role for this pathway in both the initiation and progression of autoimmune diseases.


Assuntos
Doenças Autoimunes/imunologia , Autoimunidade , Ativação Linfocitária , Animais , Humanos
12.
Hum Vaccin Immunother ; 12(5): 1250-6, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-26833132

RESUMO

We examined the coverage and timing of rotavirus vaccination and the impact of rotavirus vaccine introduction on coverage and timing of the pentavalent vaccine. We used data from the Demographic and Health Surveys in Honduras (2011/2012) and Peru (2012). The samples were divided into 2 subcohorts: children born before and after the introduction of rotavirus vaccine. We compared coverage and timing of the pentavalent vaccine in the aforementioned subcohorts. Coverage with the first and second doses of rotavirus vaccination was 95% (95% confidence intervals: 93-97%) and 91% (89-95%) in Honduras and 79% (77-82%) and 72% (69-75%) in Peru, respectively. Coverage increased in both countries over the years. The proportion of children vaccinated according to age-appropriate vaccination schedules varied between 67% (second dose of rotavirus vaccinations in Peru) and 89% (first dose of rotavirus vaccination in Honduras). Coverage with the first and second doses of pentavalent vaccination remained constant over the years in Honduras, while in Peru there was a significant increase in coverage over the years (p for trend, <0.0001). In both countries, timing of pentavalent vaccination was better in post-rota-cohorts than in pre-rota-cohorts. Since its introduction, coverage of rotavirus vaccination has improved over time in both countries. An introduction of rotavirus vaccination in both countries appears to have improved the coverage and timing of other similarly scheduled vaccinations.


Assuntos
Esquemas de Imunização , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/administração & dosagem , Vacinação , Feminino , Honduras , Humanos , Lactente , Masculino , Peru , Fatores de Tempo , Vacinas Atenuadas/administração & dosagem
13.
Leukemia ; 7(8): 1211-8, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8350620

RESUMO

Purified blast cells from peripheral blood of 12 patients, with chronic myelogenous leukemia (CML) in chronic phase, were analyzed for the constitutive expression of the granulocyte-macrophage colony-stimulating factor (GM-CSF) transcript. Seven out 12 patients exhibited the specific 1.0 kb GM-CSF mRNA. Six from these patients presented an increased level of spontaneous megakaryocytic colony formation. Using an immunocytochemical procedure, the presence of GM-CSF was detected in a large proportion (52% to 72%) of the blast cells of the three patients studied, who were selected for the high expression of GM-CSF mRNA transcripts. Because the role of GM-CSF in the regulation of human megakaryocytopoiesis is well documented, we investigated the inhibiting effect of anti-GM-CSF antibodies on the spontaneous megakaryocytic colony growth of three of the patients expressing the GM-CSF transcript. Addition of anti-GM-CSF had a high neutralizing effect ranging from 60% to 70% inhibition of endogenous megakaryocytic colony growth. As the GM-CSF synthesis by leukemic cells is often induced by interleukin-1 (IL-1), we also investigated the effect of anti-IL-1 antibody on the spontaneous megakaryocytic colony growth of the same three patients. No significant inhibiting effect was observed, showing that the role of GM-CSF in the spontaneous colony formation is not mediated by IL-1. In addition, patients who constitutively expressed the GM-CSF transcript and showed endogenous megakaryocytic colony growth were those having a significantly higher platelet count than the group of patients without GM-CSF transcript and with no endogenous megakaryocytic colonies. In conclusion, these results suggest that GM-CSF, but not IL-1, participates in the production of spontaneous megakaryocytic colony formation observed in some CML patients. The true autocrine or paracrine nature of this stimulation remains to be established.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Leucemia Mieloide de Fase Crônica/sangue , Megacariócitos/patologia , RNA Mensageiro/sangue , Anticorpos/farmacologia , Ensaio de Unidades Formadoras de Colônias , Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Interleucina-1/imunologia , Leucemia Mieloide de Fase Crônica/genética , Leucemia Mieloide de Fase Crônica/patologia , Contagem de Plaquetas , Células Tumorais Cultivadas/patologia
14.
Exp Hematol ; 15(7): 750-8, 1987 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3301382

RESUMO

The proliferation and differentiation of human megakaryocytes in liquid culture has been obtained using cryopreserved light-density blood cell concentrates from chronic myelogenous leukemia (CML) patients. A large number of megakaryocytes, representing 20%-60% of total cells cultured, developed after 12-14 days in liquid cultures supplemented with human plasma, while fetal calf serum supported the development of cells of the megakaryocytic lineage poorly. Ploidy studies showed the presence of 8N and 16N cells in human plasma-supplemented cultures while very few cells with DNA content greater than 4N were found in those supplemented with fetal calf serum. Using the FACS IV cytofluorometer, 1-2 X 10(6) megakaryocytes/h were sorted after immunolabeling of the human plasma-cultured cells with a monoclonal antibody reacting against the platelet glycoprotein complex IIb-IIIa. Thus, cryopreserved CML blood stem cell concentrates seem to offer a reproducible source of human megakaryocytes that retain their capacity to proliferate and differentiate in liquid cultures. These megakaryocytes can be used for the study of platelet glycoprotein biosynthesis as well as the regulation of megakaryocytopoiesis.


Assuntos
Leucemia Mieloide/patologia , Megacariócitos/citologia , Células-Tronco/citologia , Coleta de Amostras Sanguíneas , Diferenciação Celular , Divisão Celular , DNA/análise , Citometria de Fluxo , Imunofluorescência , Congelamento , Humanos , Glicoproteínas da Membrana de Plaquetas/análise
15.
Exp Hematol ; 25(6): 481-90, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9197325

RESUMO

Murine embryonic stem (ES) cells are able to differentiate into erythroid, mast, and granulomonocytic cells by using appropriate culture conditions. Because we were interested in the regulation of tissue-specific expression of the platelet glycoprotein IIb gene, we studied the culture conditions, aiming at the reproducible production of myeloid cells that included megakaryocytes (MKs) from ES cells. We showed that even a complex cocktail of HGFs (stem cell factor, interleukin 3, IL6, IL11, granulocyte colony-stimulating factor, and erythropoietin) is unable to induce significant myeloid differentiation in day 12 embryoid bodies. Cocultures of MS-5 stromal cells with ES cells were slightly more productive than HGFs. A strong synergistic effect was observed on the growth of myeloid colonies and MKs when we used a combination of MS-5 cells plus the HGF cocktail. Conditioned medium from MS-5 cells also synergized with the HGF cocktail to produce a substantial number of mixed colonies containing MKs. The addition of fibroblast growth factor-2 (FGF-2) to the HGF cocktail plus MS-5 nearly doubled the number of myeloid progenitors, including those with MKs. Thrombopoietin (TPO) alone or in any combination with MS-5 or HGFs, did not increase the number of MK-containing colonies. However, when TPO was added to the HGF cocktail + FGF-2 + MS-5, the number of MKs in liquid cultures and mixed colonies increased, and many exhibited a "hairy" appearance resembling pseudopodial proplatelet formation. Having defined the culture conditions of ES cells that allow the production of all the myeloid lineages including MKs, we conclude that the hematopoietic differentiation model of ES cells is especially useful for studying the regulation of expression of any gene important in early hematopoiesis.


Assuntos
Blastocisto/citologia , Células da Medula Óssea , Hematopoese , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Células-Tronco Hematopoéticas/citologia , Megacariócitos/citologia , Células-Tronco/citologia , Animais , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Fator 2 de Crescimento de Fibroblastos/farmacologia , Expressão Gênica , Camundongos , RNA Mensageiro/genética , Trombopoetina/farmacologia
16.
Exp Hematol ; 10(2): 196-205, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6977458

RESUMO

Conditioned media prepared using human placenta, spleen, bone marrow and peripheral blood leucocytes revealed a common pattern of two distinct species of colony-stimulating factors (CSF) separable by gel filtration. The peak of greatest activity, active against both human and mouse marrow, had an apparent molecular weight (MW) of 24,000-28,000 Daltons. A peak of low activity detected only against mouse marrow had an apparent MW of approximately 150,000 Daltons. The type of progenitor cells stimulated by the crude medium, by the low MW CSF species, and by the high MW species were similar for the four conditioned media despite their different origins. No difference was found in either the MW of the human active CSF present or the type of progenitor cells stimulated by media conditioned with cells of leukemic origin.


Assuntos
Medula Óssea/análise , Fatores Estimuladores de Colônias , Placenta/análise , Baço/análise , Animais , Células da Medula Óssea , Cromatografia em Gel , Meios de Cultura , Relação Dose-Resposta a Droga , Humanos , Leucócitos/análise , Camundongos , Camundongos Endogâmicos C57BL , Peso Molecular
17.
Exp Hematol ; 10(7): 578-86, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6957307

RESUMO

A simple density-cut separation technique is described for obtaining GM-CFC concentrates from the peripheral blood of patients with chronic granulocytic leukemia (CGL) for autografting at the acute blastic phase of the disease. Large numbers of granulomonocytic colony forming cells (GM-CFC) were recovered from a single procedure (68.4 X 10(6) GM-CFC). The cryopreservation of these concentrates in liquid nitrogen allowed the recovery of 46.6 +/- 33.8% viable GM-CFC. An improved yield of GM-CFC was obtained by avoiding washing the cells (65.2 +/- 41.1%). The separation technique resulted in a concentrated suspension of progenitors in a small volume of medium (mean = 15 ml) allowing a great reduction in the amount of the cryoprotective agent injected into the patient at autografting. Preliminary data obtained in 4 patients transfused in blastic crisis after chemotherapy, with or without TBI, indicated the capacity of stored concentrates to repopulate these patients.


Assuntos
Separação Celular/métodos , Granulócitos/transplante , Leucemia Mieloide/terapia , Monócitos/transplante , Adulto , Sobrevivência Celular/efeitos dos fármacos , Centrifugação com Gradiente de Concentração , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Feminino , Congelamento , Granulócitos/citologia , Hematopoese , Humanos , Leucaférese , Leucemia Mieloide/sangue , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Transplante Autólogo
18.
Clin Neuroradiol ; 25(2): 143-50, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24474262

RESUMO

BACKGROUND AND PURPOSE: Molecular and genetic testing is becoming increasingly relevant in GBM. We sought to determine whether dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) perfusion imaging could predict EGFR-defined subtypes of GBM. MATERIALS AND METHODS: We retrospectively identified 106 consecutive glioblastoma (GBM) patients with known EGFR gene amplification, and a subset of 65 patients who also had known EGFRvIII gene mutation status. All patients underwent T2* DSC MRI perfusion. DSC perfusion maps and T2* signal intensity time curves were evaluated, and the following measures of tumor perfusion were recorded: (1) maximum relative cerebral blood volume (rCBV), (2) relative peak height (rPH), and (3) percent signal recovery (PSR). The imaging metrics were correlated to EGFR gene amplification and EGFRvIII mutation status using univariate analyses. RESULTS: EGFR amplification was present in 44 (41.5 %) subjects and absent in 62 (58.5 %). Among the 65 subjects who had undergone EGFRvIII mutation transcript analysis, 18 subjects (27.7 %) tested positive for the EGFRvIII mutation, whereas 47 (72.3 %) did not. Higher median rCBV (3.31 versus 2.62, p = 0.01) and lower PSR (0.70 versus 0.78, p = 0.03) were associated with high levels of EGFR amplification. Higher median rPH (3.68 versus 2.76, p = 0.03) was associated with EGFRvIII mutation. CONCLUSION: DSC MRI perfusion may have a role in identifying patients with EGFR gene amplification and EGFRvIII gene mutation status, potential targets for individualized treatment protocols. Our results raise the need for further investigation for imaging biomarkers of genetically unique GBM subtypes.


Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/genética , Meios de Contraste , Receptores ErbB/genética , Amplificação de Genes/genética , Glioblastoma/irrigação sanguínea , Glioblastoma/genética , Interpretação de Imagem Assistida por Computador , Angiografia por Ressonância Magnética/métodos , Volume Sanguíneo/fisiologia , Neoplasias Encefálicas/cirurgia , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/cirurgia , Humanos , Masculino , Lobo Occipital/irrigação sanguínea , Lobo Occipital/patologia , Lobo Occipital/cirurgia , Estudos Retrospectivos , Estatística como Assunto
19.
Proc Biol Sci ; 247(1319): 107-12, 1992 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-1349176

RESUMO

It is well established that specific unresponsiveness to immunization can be induced by prolonged exposure to antigenic proteins. More generally, many parasitic infections, such as the helminth worms and the Leishmania parasites, appear to be able to persist in some of their human hosts over long periods of time, via what appears to be an ability to induce defective or inappropriate T-cell responses (= tolerance). Recent research has suggested that cytokines, produced by specific subsets of CD4+ T-cells (characterized by cytokine secretory profiles and growth properties), have an important, and often complex, role in promoting or inhibiting host protective immunity to parasitic infections. By examination of the population dynamics of the stimulation and regulation of cellular responses to infection, via the use of simple mathematical models, we show that nonlinear interactions between CD4+ T-cell subsets and their secreted cytokines can result in either host protection or immunological unresponsiveness, depending on the magnitude and duration of exposure to parasitic infection. Analyses also identify a possible mechanism to explain the stimulation of two separate peaks of enhanced T-cell-mediated responses over a wide range of levels of antigenic exposure.


Assuntos
Doenças Parasitárias/imunologia , Animais , Citocinas , Interações Hospedeiro-Parasita/imunologia , Humanos , Tolerância Imunológica , Ativação Linfocitária , Modelos Biológicos , Subpopulações de Linfócitos T/imunologia
20.
Thromb Haemost ; 72(6): 931-6, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7740466

RESUMO

Platelets have been described to contain a large proportion of the circulating plasminogen activator inhibitor type 1 (PAI-1) which is released on platelet activation. This protein could be taken up by platelets from the plasma or synthesized by megakaryocytes (MKs). Recently, PAI-1 mRNA has been detected in a human megakaryoblastic leukemia cell line (MEG-01) by the polymerase chain reaction (PCR). However, a direct-demonstration of its presence in normal human MKs is lacking. In order to prove directly the megakaryocytic origin of platelet PAI-1, the MEG-01 cell line, human bone marrow enriched in MKs, and bone marrow smears from allogeneic bone marrow transplantation donors were investigated for the presence of PAI-1 mRNA using in situ hybridization (ISH). Specimens of bone marrow were first stained with May-Grünwald Giemsa (MGG) for cell identification according to their morphology. Subsequently, the same slides were used for ISH. PAI-1 mRNA was clearly demonstrated in the MEG-01 cell line and in MKs, and its presence correlated with the detection of PAI-1 antigen by immunocytochemistry. PAI-1 mRNA was also detected in morphologically characterized mature granulocytes of marrow samples.


Assuntos
Megacariócitos/química , Inibidor 1 de Ativador de Plasminogênio/genética , RNA Mensageiro/análise , Medula Óssea/química , Células da Medula Óssea , Transplante de Medula Óssea/fisiologia , Contagem de Células , Linhagem Celular , Humanos , Imuno-Histoquímica , Hibridização In Situ , Transplante Homólogo
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