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1.
JAMA Neurol ; 80(12): 1334-1343, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37870862

RESUMO

Importance: Cryptogenic sensory peripheral neuropathy (CSPN) is highly prevalent and often disabling due to neuropathic pain. Metabolic syndrome and its components increase neuropathy risk. Diet and exercise have shown promise but are limited by poor adherence. Objective: To determine whether topiramate can slow decline in intraepidermal nerve fiber density (IENFD) and/or neuropathy-specific quality of life measured using the Norfolk Quality of Life-Diabetic Neuropathy (NQOL-DN) scale. Design, Setting, and Participants: Topiramate as a Disease-Modifying Therapy for CSPN (TopCSPN) was a double-blind, placebo-controlled, randomized clinical trial conducted between February 2018 and October 2021. TopCSPN was performed at 20 sites in the National Institutes of Health-funded Network for Excellence in Neurosciences Clinical Trials (NeuroNEXT). Individuals with CSPN and metabolic syndrome aged 18 to 80 years were screened and randomly assigned by body mass index (<30 vs ≥30), which is calculated as weight in kilograms divided by height in meters squared. Patients were excluded if they had poorly controlled diabetes, prior topiramate treatment, recurrent nephrolithiasis, type 1 diabetes, use of insulin within 3 months before screening, history of foot ulceration, planned bariatric surgery, history of alcohol or drug overuse in the 2 years before screening, family history of a hereditary neuropathy, or an alternative neuropathy cause. Interventions: Participants received topiramate or matched placebo titrated to a maximum-tolerated dose of 100 mg per day. Main Outcomes and Measures: IENFD and NQOL-DN score were co-primary outcome measures. A positive study was defined as efficacy in both or efficacy in one and noninferiority in the other. Results: A total of 211 individuals were screened, and 132 were randomly assigned to treatment groups: 66 in the topiramate group and 66 in the placebo group. Age and sex were similar between groups (topiramate: mean [SD] age, 61 (10) years; 38 male [58%]; placebo: mean [SD] age, 62 (11) years; 44 male [67%]). The difference in change in IENFD and NQOL-DN score was noninferior but not superior in the intention-to-treat (ITT) analysis (IENFD, 0.21 fibers/mm per year; 95% CI, -0.43 to ∞ fibers/mm per year and NQOL-DN score, -1.52 points per year; 95% CI, -∞ to 1.19 points per year). A per-protocol analysis excluding noncompliant participants based on serum topiramate levels and those with major protocol deviations demonstrated superiority in NQOL-DN score (-3.69 points per year; 95% CI, -∞ to -0.73 points per year). Patients treated with topiramate had a mean (SD) annual change in IENFD of 0.56 fibers/mm per year relative to placebo (95% CI, -0.21 to ∞ fibers/mm per year). Although IENFD was stable in the topiramate group compared with a decline consistent with expected natural history, this difference did not demonstrate superiority. Conclusion and Relevance: Topiramate did not slow IENFD decline or affect NQOL-DN score in the primary ITT analysis. Some participants were intolerant of topiramate. NQOL-DN score was superior among those compliant based on serum levels and without major protocol deviations. Trial Registration: ClinicalTrials.gov Identifier: NCT02878798.


Assuntos
Neuropatias Diabéticas , Síndrome Metabólica , Neuralgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuropatias Diabéticas/tratamento farmacológico , Método Duplo-Cego , Síndrome Metabólica/complicações , Síndrome Metabólica/tratamento farmacológico , Qualidade de Vida , Topiramato/efeitos adversos , Adolescente , Adulto Jovem , Adulto , Idoso de 80 Anos ou mais
2.
BMC Public Health ; 21(1): 1159, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34134674

RESUMO

INTRODUCTION: Healthy Beginnings is an established nurse-led early childhood obesity prevention program that promotes healthy infant feeding practices and active play in the early years of life. To improve engagement with culturally and linguistically diverse populations, the Healthy Beginnings program delivered by telephone was culturally adapted and implemented with Arabic- and Chinese-speaking mothers in Sydney, Australia. The cultural adaptation process has been published separately. In this article, we aimed to evaluate the feasibility of the culturally adapted program. METHODS: In 2018-2019, the culturally adapted Healthy Beginnings program was implemented with Arabic- and Chinese-speaking women recruited from antenatal clinics in Sydney. At four staged timepoints (from third trimester until 6 months of age), mothers were sent culturally adapted health promotion booklets and text messages and offered four support calls from bi-cultural child and family health nurses in Arabic and Chinese. A mixed methods evaluation included a) baseline and 6-month telephone surveys, followed by b) semi-structured follow-up interviews with a subset of participating mothers and program delivery staff. Main outcomes of this feasibility study were reach (recruitment and retention), intervention dose delivered (number of nurse support calls completed) and acceptability (appropriateness based on cognitive and emotional responses). RESULTS: At recruitment, 176 mothers were eligible and consented to participate. Of 163 mothers who completed the baseline survey, 95% completed the program (n = 8 withdrew) and 83% completed the 6-month survey (n = 70 Arabic- and n = 65 Chinese-speaking mothers). Most mothers (n = 127, 78%) completed at least one nurse support call. The qualitative analysis of follow-up interviews with 42 mothers (22 Arabic- and 20 Chinese-speaking mothers) and 10 program delivery staff highlighted the perceived value of the program and the positive role of bi-cultural nurses and in-language resources. Mothers who completed more nurse support calls generally expressed greater acceptability. CONCLUSIONS: The culturally adapted Healthy Beginnings program was feasible to deliver and acceptable to Arabic- and Chinese-speaking mothers. Our results highlight the importance of in-language resources and individualised bi-cultural nurse support by telephone for supporting culturally and linguistically diverse migrant families with infant feeding and active play. These findings support the potential for program refinements and progression to an effectiveness trial.


Assuntos
Obesidade Infantil , Migrantes , Austrália , Criança , Pré-Escolar , Estudos de Viabilidade , Feminino , Humanos , Lactente , Mães , Gravidez
3.
BMC Public Health ; 21(1): 284, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33541310

RESUMO

BACKGROUND: Behavioural interventions for the early prevention of childhood obesity mostly focus on English-speaking populations in high-income countries. Cultural adaptation is an emerging strategy for implementing evidence-based interventions among different populations and regions. This paper describes the initial process of culturally adapting Healthy Beginnings, an evidence-based early childhood obesity prevention program, for Arabic and Chinese speaking migrant mothers and infants in Sydney, Australia. METHODS: The cultural adaptation process followed the Stages of Cultural Adaptation theoretical model and is reported using the Framework for Reporting Adaptations and Modifications-Enhanced. We first established the adaptation rationale, then considered program underpinnings and the core components for effectiveness. To inform adaptations, we reviewed the scientific literature and engaged stakeholders. Consultations included focus groups with 24 Arabic and 22 Chinese speaking migrant mothers and interviews with 20 health professionals. With input from project partners, bi-cultural staff and community organisations, findings informed cultural adaptations to the content and delivery features of the Healthy Beginnings program. RESULTS: Program structure and delivery mode were retained to preserve fidelity (i.e. staged nurse calls with key program messages addressing modifiable obesity-related behaviours: infant feeding, active play, sedentary behaviours and sleep). Qualitative analysis of focus group and interview data resulted in descriptive themes concerning cultural practices and beliefs related to infant obesity-related behaviours and perceptions of child weight among Arabic and Chinese speaking mothers. Based on the literature and local study findings, cultural adaptations were made to recruitment approaches, staffing (bi-cultural nurses and project staff) and program content (modified call scripts and culturally adapted written health promotion materials). CONCLUSIONS: This cultural adaptation of Healthy Beginnings followed an established process model and resulted in a program with enhanced relevance and accessibility among Arabic and Chinese speaking migrant mothers. This work will inform the future cultural adaptation stages: testing, refining, and trialling the culturally adapted Healthy Beginnings program to assess acceptability, feasibility and effectiveness.


Assuntos
Mães , Obesidade Infantil , Austrália , Criança , Pré-Escolar , China , Feminino , Promoção da Saúde , Humanos , Lactente , Obesidade Infantil/prevenção & controle
4.
Neurology ; 96(4): e491-e500, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33268562

RESUMO

OBJECTIVE: To determine whether ibudilast has an effect on brain volume and new lesions in progressive forms of multiple sclerosis (MS). METHODS: A randomized, placebo-controlled, blinded study evaluated ibudilast at a dose of up to 100 mg over 96 weeks in primary and secondary progressive MS. In this secondary analysis of a previously reported trial, secondary and tertiary endpoints included gray matter atrophy, new or enlarging T2 lesions as measured every 24 weeks, and new T1 hypointensities at 96 weeks. Whole brain atrophy measured by structural image evaluation, using normalization, of atrophy (SIENA) was a sensitivity analysis. RESULTS: A total of 129 participants were assigned to ibudilast and 126 to placebo. New or enlarging T2 lesions were observed in 37.2% on ibudilast and 29.0% on placebo (p = 0.82). New T1 hypointense lesions at 96 weeks were observed in 33.3% on ibudilast and 23.5% on placebo (p = 0.11). Gray matter atrophy was reduced by 35% for those on ibudilast vs placebo (p = 0.038). Progression of whole brain atrophy by SIENA was slowed by 20% in the ibudilast group compared with placebo (p = 0.08). CONCLUSION: Ibudilast treatment was associated with a reduction in gray matter atrophy. Ibudilast treatment was not associated with a reduction in new or enlarging T2 lesions or new T1 lesions. An effect on brain volume contributes to prior data that ibudilast appears to affect markers associated with neurodegenerative processes, but not inflammatory processes. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for people with MS, ibudilast does not significantly reduce new or enlarging T2 lesions or new T1 lesions.


Assuntos
Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/tratamento farmacológico , Piridinas/uso terapêutico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores de Fosfodiesterase/uso terapêutico , Resultado do Tratamento
5.
Women Birth ; 34(4): e346-e356, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32600988

RESUMO

Optimal feeding practices can establish lifelong, transgenerational and global health benefits. Migration and cultural factors impact infant feeding practices and the support mothers receive for optimal infant feeding. This qualitative study explored support for infant feeding among Arabic and Chinese speaking migrant mothers in Australia. Semi-structured focus groups were conducted in language with 24 Arabic and 22 Chinese-Mandarin speaking migrant mothers with children under five years of age. Individual interviews were conducted in English with 20 health professionals working with Arabic or Chinese speaking migrant families. Data were thematically analysed using the framework method. Traditional family networks and trusted bi-cultural doctors were influential infant feeding supports for mothers. Health professionals perceived maternal and child health services to be poorly understood, and some mothers who accessed services felt they were not always culturally sensitive. Mothers sought additional information and support through online sources and peers. Both mothers and health professionals recognised the challenges of managing conflicting infant feeding advice and seeking best-practice support. The findings of this study highlight opportunities for health professionals to better support migrant mothers' infant feeding practices, for example through engaging families and working with doctors. There is a need for greater cultural sensitivity within maternal and child health services and culturally relevant programs to support healthy infant feeding practices among migrant communities.


Assuntos
Aleitamento Materno/psicologia , Assistência à Saúde Culturalmente Competente , Emigrantes e Imigrantes/psicologia , Pessoal de Saúde/psicologia , Mães/psicologia , Adulto , Árabes , Austrália/epidemiologia , Aleitamento Materno/etnologia , Criança , Pré-Escolar , China/etnologia , Emigrantes e Imigrantes/estatística & dados numéricos , Comportamento Alimentar , Feminino , Grupos Focais , Humanos , Lactente , Entrevistas como Assunto , Idioma , Masculino , Serviços de Saúde Materno-Infantil , Cuidados de Enfermagem , Grupo Associado , Pesquisa Qualitativa , Inquéritos e Questionários
6.
Lancet Neurol ; 13(11): 1083-1091, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25297012

RESUMO

BACKGROUND: Glutamate excitotoxicity might contribute to the pathophysiology of amyotrophic lateral sclerosis. In animal models, decreased excitatory aminoacid transporter 2 (EAAT2) overexpression delays disease onset and prolongs survival, and ceftriaxone increases EAAT2 activity. We aimed to assess the safety and efficacy of ceftriaxone for amyotrophic lateral sclerosis in a combined phase 1, 2, and 3 clinical trial. METHODS: This three-stage randomised, double-blind, placebo-controlled study was done at 59 clinical sites in the USA and Canada between Sept 4, 2006, and July 30, 2012. Eligible adult patients had amyotrophic lateral sclerosis, a vital capacity of more than 60% of that predicted for age and height, and symptom duration of less than 3 years. In stages 1 (pharmacokinetics) and 2 (safety), participants were randomly allocated (2:1) to ceftriaxone (2 g or 4 g per day) or placebo. In stage 3 (efficacy), participants assigned to ceftriaxone in stage 2 received 4 g ceftriaxone, participants assigned to placebo in stage 2 received placebo, and new participants were randomly assigned (2:1) to 4 g ceftriaxone or placebo. Participants, family members, and site staff were masked to treatment assignment. Randomisation was done by a computerised randomisation sequence with permuted blocks of 3. Participants received 2 g ceftriaxone or placebo twice daily through a central venous catheter administered at home by a trained caregiver. To minimise biliary side-effects, participants assigned to ceftriaxone also received 300 mg ursodeoxycholic acid twice daily and those assigned to placebo received matched placebo capsules. The coprimary efficacy outcomes were survival and functional decline, measured as the slope of Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) scores. Analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00349622. FINDINGS: Stage 3 included 66 participants from stages 1 and 2 and 448 new participants. In total, 340 participants were randomly allocated to ceftriaxone and 173 to placebo. During stages 1 and 2, mean ALSFRS-R declined more slowly in participants who received 4 g ceftriaxone than in those on placebo (difference 0·51 units per month, 95% CI 0·02 to 1·00; p=0·0416), but in stage 3 functional decline between the treatment groups did not differ (0·09, -0·06 to 0·24; p=0·2370). No significant differences in survival between the groups were recorded in stage 3 (HR 0·90, 95% CI 0·71 to 1·15; p=0·4146). Gastrointestinal adverse events and hepatobiliary adverse events were more common in the ceftriaxone group than in the placebo group (gastrointestinal, 245 of 340 [72%] ceftriaxone vs 97 of 173 [56%] placebo, p=0·0004; hepatobiliary, 211 [62%] vs 19 [11%], p<0·0001). Significantly more participants who received ceftriaxone had serious hepatobiliary serious adverse events (41 participants [12%]) than did those who received placebo (0 participants). INTERPRETATION: Despite promising stage 2 data, stage 3 of this trial of ceftriaxone in amyotrophic lateral sclerosis did not show clinical efficacy. The adaptive design allowed for seamless transition from one phase to another, and central venous catheter use in the home setting was shown to be feasible. FUNDING: National Institute of Neurological Disorders and Stroke.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/tratamento farmacológico , Ceftriaxona/efeitos adversos , Adulto , Idoso , Ceftriaxona/uso terapêutico , Método Duplo-Cego , Dispneia/induzido quimicamente , Dispneia/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
7.
Neurology ; 81(15): 1350-5, 2013 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-24005339

RESUMO

OBJECTIVE: To investigate predictors of trial start-up times, high attrition, and poor protocol adherence in amyotrophic lateral sclerosis (ALS) trials. METHODS: Retrospective analysis of start-up times, retention, and protocol adherence was performed on 5 clinical studies conducted by the Northeast ALS Consortium and 50 ALS clinical trials identified by PubMed search. Predictors of start-up times were estimated by accelerated failure time models with random effects. Predictors of retention and protocol deviations were estimated by mixed-model logistic regression. RESULTS: Median times for contract execution and institutional review board (IRB) approval were 105 days and 125 days, respectively. Contract execution was faster at sites with more ongoing trials (p = 0.005), and more full-time (p = 0.006) and experienced (p < 0.001) coordinators. IRB approval was faster at sites with more ongoing trials (p = 0.010) and larger ALS clinics (p = 0.038). Site activation after IRB approval was faster at sites with more full-time (p = 0.038) and experienced (p < 0.001) coordinators. Twenty-two percent of surviving participants withdrew before completing the trial. Better participant functional score at baseline was an independent predictor of trial completion (odds ratio 1.29, p = 0.002) and fewer protocol deviations (odds ratio 0.86, p = 0.030). CONCLUSION: Delays in IRB review contribute the most to prolonged trial start-up times, and these timelines are faster in sites with more experienced staff. Strategies to improve protocol adherence and participants' retention may include enrolling people at early disease stages.


Assuntos
Esclerose Lateral Amiotrófica/psicologia , Esclerose Lateral Amiotrófica/terapia , Ensaios Clínicos como Assunto , Cooperação do Paciente , Humanos , Modelos Logísticos , Estudos Multicêntricos como Assunto , Cooperação do Paciente/psicologia , Seleção de Pacientes , Valor Preditivo dos Testes , PubMed/estatística & dados numéricos , Projetos de Pesquisa , Estudos Retrospectivos
8.
Circulation ; 115(25): 3165-72, 2007 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-17562958

RESUMO

BACKGROUND: A growing population of patients with coronary artery disease experiences angina that is not amenable to revascularization and is refractory to medical therapy. Preclinical studies have indicated that human CD34+ stem cells induce neovascularization in ischemic myocardium, which enhances perfusion and function. METHODS AND RESULTS: Twenty-four patients (19 men and 5 women aged 48 to 84 years) with Canadian Cardiovascular Society class 3 or 4 angina who were undergoing optimal medical treatment and who were not candidates for mechanical revascularization were enrolled in a double-blind, randomized (3:1), placebo-controlled dose-escalating study. Patients received granulocyte colony-stimulating factor 5 microg x kg(-1) x d(-1) for 5 days with leukapheresis on the fifth day. Selection of CD34+ cells was performed with a Food and Drug Administration-approved device. Electromechanical mapping was performed to identify ischemic but viable regions of myocardium for injection of cells (versus saline). The total dose of cells was distributed in 10 intramyocardial, transendocardial injections. Patients were required to have an implantable cardioverter-defibrillator or to temporarily wear a LifeVest wearable defibrillator. No incidence was observed of myocardial infarction induced by mobilization or intramyocardial injection. The intramyocardial injection of cells or saline did not result in cardiac enzyme elevation, perforation, or pericardial effusion. No incidence of ventricular tachycardia or ventricular fibrillation occurred during the administration of granulocyte colony-stimulating factor or intramyocardial injections. One patient with a history of sudden cardiac death/ventricular tachycardia/ventricular fibrillation had catheter-induced ventricular tachycardia during mapping that required cardioversion. Serious adverse events were evenly distributed. Efficacy parameters including angina frequency, nitroglycerine usage, exercise time, and Canadian Cardiovascular Society class showed trends that favored CD34+ cell-treated patients versus control subjects given placebo. CONCLUSIONS: A randomized trial of intramyocardial injection of autologous CD34+ cells in patients with intractable angina was completed that provides evidence for feasibility, safety, and bioactivity. A larger phase IIb study is currently under way to further evaluate this therapy.


Assuntos
Angina Pectoris/cirurgia , Transplante de Células-Tronco de Sangue Periférico , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/induzido quimicamente , Angina Pectoris/diagnóstico por imagem , Angina Pectoris/tratamento farmacológico , Fármacos Cardiovasculares/uso terapêutico , Contagem de Células , Terapia Combinada , Método Duplo-Cego , Cardioversão Elétrica , Eletrocardiografia Ambulatorial , Tolerância ao Exercício , Feminino , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Miocárdio , Transplante de Células-Tronco de Sangue Periférico/métodos , Qualidade de Vida , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
9.
FASEB J ; 21(11): 2906-17, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17504977

RESUMO

Expression of angiogenic cytokines like vascular endothelial growth factor is enhanced by hypoxia. We tested the hypothesis that decreased oxygen levels up-regulate the angiogenic factor secretoneurin. In vivo, muscle cells of mouse ischemic hind limbs showed increased secretoneurin expression, and inhibition of secretoneurin by a neutralizing antibody impaired the angiogenic response in this ischemia model. In a mouse soft tissue model of hypoxia, secretoneurin was increased in subcutaneous muscle fibers. In vitro, secretoneurin mRNA and protein were up-regulated in L6 myoblast cells after exposure to low oxygen levels. The hypoxia-dependent regulation of secretoneurin was tissue specific and was not observed in endothelial cells, vascular smooth muscle cells, or AtT20 pituitary tumor cells. The hypoxia-dependent induction of secretoneurin in L6 myoblasts is regulated by hypoxia-inducible factor-1alpha, since inhibition of this factor using si-RNA inhibited up-regulation of secretoneurin. Induction of secretoneurin by hypoxia was dependent on basic fibroblast growth factor in vivo and in vitro, and inhibition of this regulation by heparinase suggests an involvement of low-affinity basic fibroblast growth factor binding sites. In summary, our data show that the angiogenic cytokine secretoneurin is up-regulated by hypoxia in muscle cells by hypoxia-inducible factor-1alpha- and basic fibroblast growth factor-dependent mechanisms.


Assuntos
Hipóxia Celular , Fator 2 de Crescimento de Fibroblastos/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mioblastos/metabolismo , Neuropeptídeos/metabolismo , Secretogranina II/metabolismo , Transdução de Sinais , Animais , Western Blotting , Células Cultivadas , Primers do DNA/química , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Extremidades/cirurgia , Imunofluorescência , Isquemia/metabolismo , Isquemia/patologia , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/irrigação sanguínea , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , NAD/metabolismo , Neovascularização Fisiológica , Neoplasias Hipofisárias/irrigação sanguínea , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Reação em Cadeia da Polimerase , Pró-Proteína Convertases/metabolismo , RNA Interferente Pequeno/farmacologia , Radioimunoensaio , Ratos , Pele/metabolismo , Transfecção , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Circulation ; 114(20): 2163-9, 2006 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-17075009

RESUMO

BACKGROUND: We compared the therapeutic potential of purified mobilized human CD34+ cells with that of mobilized total mononuclear cells (tMNCs) for the preservation/recovery of myocardial tissue integrity and function after myocardial infarction (MI). METHODS AND RESULTS: CD34+ cells were purified from peripheral blood tMNCs of healthy volunteers by magnetic cell sorting after a 5-day administration of granulocyte colony-stimulating factor. Phosphate-buffered saline (PBS), 5x10(5) CD34+ cells/kg, 5x10(5) tMNCs/kg (low-dose MNCs [loMNCs]), or a higher dose of tMNCs (hiMNCs) containing 5x10(5) CD34+ cells/kg was transplanted intramyocardially 10 minutes after the induction of MI in athymic nude rats. Hematoxylin and eosin staining revealed that moderate to severe hemorrhagic MI on day 3 was more frequent in the hiMNC group than in the PBS and CD34+ cell groups. Immunostaining for human-specific CD45 revealed abundant distribution of hematopoietic/inflammatory cells derived from transplanted cells in the ischemic myocardium of the hiMNC group. Capillary density on day 28 was significantly greater in the CD34+ cell group (721.1+/-19.9 per 1 mm2) than in the PBS, loMNC, and hiMNC groups (384.7+/-11.0, 372.5+/-14.1, and 497.5+/-24.0 per 1 mm2) (P<0.01). Percent fibrosis area on day 28 was less in the CD34(+) cell group (15.6+/-0.9%) than in the PBS, loMNC, and hiMNC groups (26.3+/-1.2%, 27.5+/-1.8%, and 22.2+/-1.8%) (P<0.05). Echocardiographic fractional shortening on day 28 was significantly higher in the CD34+ cell group (30.3+/-0.9%) than in the PBS, loMNC, and hiMNC groups (22.7+/-1.5%, 23.4+/-1.1%, and 24.9+/-1.7%; P<0.05). Echocardiographic regional wall motion score was better preserved in the CD34+ cell group (21.8+/-0.5) than in the PBS, loMNC, and hiMNC groups (25.4+/-0.4, 24.9+/-0.4, and 24.1+/-0.6; P<0.05). CONCLUSIONS: CD34+ cells exhibit superior efficacy for preserving myocardial integrity and function after MI than unselected circulating MNCs.


Assuntos
Antígenos CD34/metabolismo , Monócitos/metabolismo , Monócitos/transplante , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/cirurgia , Neovascularização Fisiológica , Animais , Diferenciação Celular , Ecocardiografia , Feminino , Hemorragia/etiologia , Humanos , Monócitos/patologia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/patologia , Miocárdio/patologia , Período Pós-Operatório , Ratos , Ratos Nus , Ratos Sprague-Dawley , Índice de Gravidade de Doença , Fatores de Tempo , Transplante Heterólogo , Função Ventricular Esquerda , Remodelação Ventricular
11.
Proc Natl Acad Sci U S A ; 103(29): 11015-20, 2006 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-16835303

RESUMO

The transcription factor E2F1 is known to regulate cell proliferation and has been thought to modulate tumorigenesis via this mechanism alone. Here we show that mice deficient in E2F1 exhibit enhanced angiogenesis. The proangiogenic phenotype in E2F1 deficiency is the result of overproduction of vascular endothelial growth factor (VEGF) and is prevented by VEGF blockade. Under hypoxic conditions, E2F1 down-regulates the expression of VEGF promoter activity by associating with p53 and specifically down-regulating expression of VEGF but not other hypoxia-inducible genes, suggesting a promoter structure context-dependent regulation mechanism. We found that the minimum VEGF promoter mediating transcriptional repression by E2F1 features an E2F1- binding site with four Sp-1 sites in close proximity. These data disclose an unexpected function of endogenous E2F1: regulation of angiogenic activity via p53-dependent transcriptional control of VEGF expression.


Assuntos
Ciclo Celular , Fator de Transcrição E2F1/metabolismo , Transcrição Gênica/genética , Proteína Supressora de Tumor p53/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Células Cultivadas , Regulação para Baixo , Fator de Transcrição E2F1/deficiência , Fator de Transcrição E2F1/genética , Membro Posterior/irrigação sanguínea , Membro Posterior/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Supressora de Tumor p53/genética
12.
Nat Clin Pract Cardiovasc Med ; 3 Suppl 1: S123-8, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16501618

RESUMO

Previous studies have shown that local angiogenic gene therapy acts, in part, by recruiting endothelial progenitor cells (EPCs) to ischemic tissue. Recent data indicate that patients with the most severe vascular disease may have insufficient or deficient EPCs and the poorest response to angiogenic therapy. Accordingly, we hypothesized that combining human CD34(+) cell implantation with local vascular endothelial growth factor 2 (phVEGF2) gene therapy might overcome these deficiencies. The addition of VEGF2 to EPC cultures resulted in significant and dose-dependent decreases in EPC apoptosis. Phosphorylated Akt (p-Akt) was increased in VEGF2-treated EPCs. In vivo, myocardial infarction (MI) was induced by ligation of the left anterior descending coronary artery in 34 immunodeficient rats. The animals were then randomized to one of four treatment groups: cell therapy alone with human CD34(+) cells; VEGF2 gene therapy alone; combination therapy with CD34(+) cells plus phVEGF2; or CD34(-) cells and 50 microg empty plasmid. Four weeks after MI, animals treated with combination therapy showed improved fractional shortening, increased capillary density, and reduced infarct size compared with the other three groups. Combination therapy was also associated with an increased number of circulating EPCs 1 week after MI. Combined subtherapeutic doses of cell and gene therapy result in a significant therapeutic effect compared to monotherapy. This approach may overcome therapeutic failures (e.g. inability of certain patients to mobilize sufficient EPCs) and may also offer safety advantages by allowing lower dosing strategies.


Assuntos
Antígenos CD34/análise , Células Endoteliais/transplante , Infarto do Miocárdio/terapia , Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Apoptose , Células Cultivadas , Terapia Combinada , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Feminino , Terapia Genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/patologia , Ratos , Ratos Nus , Transplante Autólogo , Fatores de Crescimento do Endotélio Vascular/genética , Fatores de Crescimento do Endotélio Vascular/farmacologia
13.
J Exp Med ; 203(1): 153-63, 2006 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-16401693

RESUMO

The cell surface receptor alpha4 integrin plays a critical role in the homing, engraftment, and maintenance of hematopoietic progenitor cells (HPCs) in the bone marrow (BM). Down-regulation or functional blockade of alpha4 integrin or its ligand vascular cell adhesion molecule-1 mobilizes long-term HPCs. We investigated the role of alpha4 integrin in the mobilization and homing of BM endothelial progenitor cells (EPCs). EPCs with endothelial colony-forming activity in the BM are exclusively alpha4 integrin-expressing cells. In vivo, a single dose of anti-alpha4 integrin antibody resulted in increased circulating EPC counts for 3 d. In hindlimb ischemia and myocardial infarction, systemically administered anti-alpha4 integrin antibody increased recruitment and incorporation of BM EPCs in newly formed vasculature and improved functional blood flow recovery and tissue preservation. Interestingly, BM EPCs that had been preblocked with anti-alpha4 integrin ex vivo or collected from alpha4 integrin-deficient mice incorporated as well as control cells into the neovasculature in ischemic sites, suggesting that alpha4 integrin may be dispensable or play a redundant role in EPC homing to ischemic tissue. These data indicate that functional disruption of alpha4 integrin may represent a potential angiogenic therapy for ischemic disease by increasing the available circulating supply of EPCs.


Assuntos
Integrina alfa4/metabolismo , Isquemia Miocárdica/fisiopatologia , Neovascularização Fisiológica , Células-Tronco/fisiologia , Animais , Medula Óssea , Movimento Celular , Células Endoteliais , Integrina alfa4/genética , Masculino , Camundongos , Camundongos Knockout
14.
J Clin Apher ; 21(2): 116-20, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16342193

RESUMO

Information on the safety of mobilization and collection of peripheral blood progenitor cells (PBPC) in patients with advanced coronary heart disease (CHD) is limited. We report herein our early experience with patients participating in a Phase I trial of injection of autologous CD 34(+) cells into threatened, ischemic myocardium for neovascularization and symptom relief in patients with chronic refractory myocardial ischemia. All patients had advanced inoperable CHD despite the best medical therapy. Granulocyte colony stimulating factor (G-CSF, 5 microg/kg/day) was administered subcutaneously for 5 days for mobilization of CD34(+) cells into the peripheral blood. PBPCs were collected in the outpatient apheresis suite on day 5. Nine patients from our institution were evaluable. Adverse effects of mobilization included: increase in frequency and/or intensity of angina in 8 patients (88.8%); bone pain in 7 patients (77.7%); headaches in 4 patients (44.4%); 2 patients (22%) were hospitalized. Collection phase toxicities included: tingling in 5 patients (55.5%) and angina in 3 patients (33%). All procedures were completed without new myocardial infarction, congestive heart failure, or death. The median peripheral blood CD34(+) cell count on day 5 of G-CSF was 21 cells/microl (range 10-40 cells/microl). A median of 1.65 x 10(6) CD34(+) cells/kg (range: 0.13-3.0 x 10(6)/kg) were harvested. We conclude that mobilization and collection of PBPC in patients with advanced CHD can be safely performed as an outpatient procedure. Apheresis professionals should be aware of the intensity and frequency of angina in this patient population.


Assuntos
Doença das Coronárias/terapia , Mobilização de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco de Sangue Periférico/métodos , Idoso , Idoso de 80 Anos ou mais , Angina Pectoris/etiologia , Doença Crônica , Doença das Coronárias/complicações , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Cefaleia/etiologia , Mobilização de Células-Tronco Hematopoéticas/normas , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/terapia , Neovascularização Fisiológica , Dor/etiologia , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Terapia de Salvação/métodos , Método Simples-Cego , Transplante Autólogo
15.
Nat Med ; 11(11): 1197-204, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16244652

RESUMO

Sonic hedgehog (Shh) is a crucial regulator of organ development during embryogenesis. We investigated whether intramyocardial gene transfer of naked DNA encoding human Shh (phShh) could promote a favorable effect on recovery from acute and chronic myocardial ischemia in adult animals, not only by promoting neovascularization, but by broader effects, consistent with the role of this morphogen in embryogenesis. After Shh gene transfer, the hedgehog pathway was upregulated in mammalian fibroblasts and cardiomyocytes. This resulted in preservation of left ventricular function in both acute and chronic myocardial ischemia by enhanced neovascularization, and reduced fibrosis and cardiac apoptosis. Shh gene transfer also enhanced the contribution of bone marrow-derived endothelial progenitor cells to myocardial neovascularization. These data suggest that Shh gene therapy may have considerable therapeutic potential in individuals with acute and chronic myocardial ischemia by triggering expression of multiple trophic factors and engendering tissue repair in the adult heart.


Assuntos
Terapia Genética , Coração/embriologia , Miocárdio/metabolismo , Transdução de Sinais , Transativadores/uso terapêutico , Doença Aguda , Animais , Células COS , Células Cultivadas , Chlorocebus aethiops , Doença Crônica , Modelos Animais de Doenças , Ecocardiografia , Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog , Humanos , Camundongos , Camundongos Mutantes , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/terapia , Miocárdio/citologia , Miócitos Cardíacos/metabolismo , Neovascularização Fisiológica , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Função Ventricular Esquerda/fisiologia
16.
Vasc Med ; 10(1): 15-22, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15920995

RESUMO

Hyperhomocyst(e)inemia (HH) is an established independent risk factor for coronary, cerebral and peripheral vascular diseases. Recent studies have indicated that certain cardiovascular risk factors, including diabetes and hypercholesterolemia, impair expression of vascular endothelial growth factor (VEGF) and endogenous angiogenesis. In this study, we investigate the impact of moderate HH on angiogenesis and VEGF pathway in a mouse model of hindlimb ischemia. Upon induction of unilateral hindlimb ischemia, endogenous angiogenesis, expression of VEGF, and phosphorylation of the VEGF receptor Flk-1 were evaluated in mice heterozygous for a deletion of the cystathionine beta-synthase gene (CBS) and compared with those observed in CBS+/+ mice. CBS+/- mice exhibit moderate HH, as demonstrated by measuring plasma total homocyst(e)ine (tHcy) levels, which were significantly higher in these animals compared with CBS+/+ mice (4.77 +/- 0.82 vs 2.10 +/- 0.28, p < 0.01). Twenty-eight days after induction of ischemia, hindlimb blood flow was significantly reduced in CBS+/- mice compared with CBS+/+ animals (0.49 +/- 0.03, n = 12 vs 0.71 +/- 0.09, n = 10; p < 0.05). In addition, there was a significant negative correlation between plasma homocyst(e)ine levels and the laser Doppler perfusion ratio in CBS+/- mice (p = 0.0087, r = -0.7171). While VEGF expression and Flk-1 phosphorylation were not impaired in the ischemic muscles of CBS+/- mice, phosphorylation of the endothelial cell survival factor Akt was significantly inhibited by homocyst(e)ine in a dose-dependent manner in human umbilical vein endothelial cell (HUVECs) in vitro. In conclusion, our findings demonstrate that endogenous angiogenesis is inversely related to plasma levels of homocyst(e)ine in genetically engineered, heterozygous mice with moderate HH. This impairment, however, is not dependent on reduced expression of VEGF or impaired phosphorylation of its receptor Flk-1. In contrast, our data suggest that impaired Akt phosphorylation mediates the impairment of angiogenesis associated with HH.


Assuntos
Hiper-Homocisteinemia/fisiopatologia , Isquemia/sangue , Neovascularização Fisiológica/fisiologia , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos , Fosforilação , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
17.
Arterioscler Thromb Vasc Biol ; 24(11): 2102-7, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15358602

RESUMO

OBJECTIVE: The embryonic morphogen sonic hedgehog (SHh) has been shown to induce neovascularization of ischemic tissue but has not been shown to play a role in regulating vascular nerve supply. Accordingly, we investigated the hypothesis that systemic injection of SHh protein could improve nerve blood flow and function in diabetic neuropathy (DN). METHODS AND RESULTS: Twelve weeks after induction of diabetes with streptozotocin, motor and sensory nerve conduction velocities (MCV and SCV) of the sciatic nerves were significantly reduced in diabetic rats. SHh-treated diabetic rats demonstrated marked improvement of both MCV and SCV (P<0.05). Laser Doppler perfusion imaging showed that nerve blood flow was significantly reduced in the diabetic rats but was restored in SHh-treated diabetic rats (P<0.05 versus diabetic saline-treated rats) to levels similar to those achieved with vascular endothelial growth factor-2 (VEGF-2) gene therapy. In vivo perfusion of Bandeuraea simplicifolia (BS)-1 lectin showed marked reduction in the vasa nervora in diabetic sciatic nerves but restoration of nerve vasculature to nondiabetic levels in the SHh-treated and plasmid DNA encoding human VEGF-2 (phVEGF-2)-treated diabetic nerves. Interestingly, the SHh-induced vasculature was characterized by larger diameter and more smooth muscle cell-containing vessels, compared with VEGF-2 gene-treated diabetic rats. CONCLUSIONS: These data indicate that Shh induces arteriogenesis and restores nerve function in DN.


Assuntos
Diabetes Mellitus Experimental/sangue , Neuropatias Diabéticas/sangue , Neovascularização Fisiológica/efeitos dos fármacos , Transativadores/farmacologia , Vasa Nervorum/efeitos dos fármacos , Vasa Nervorum/crescimento & desenvolvimento , Animais , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/metabolismo , Modelos Animais de Doenças , Fibroblastos/citologia , Proteínas Hedgehog , Humanos , Fluxometria por Laser-Doppler/métodos , Masculino , Condução Nervosa/efeitos dos fármacos , Condução Nervosa/fisiologia , Perfusão/métodos , Lectinas de Plantas/análise , Lectinas de Plantas/metabolismo , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Nervo Isquiático/irrigação sanguínea , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/fisiologia , Estreptozocina , Vasa Nervorum/química , Vasa Nervorum/patologia , Fator A de Crescimento do Endotélio Vascular/farmacologia
18.
Circulation ; 110(11): 1398-405, 2004 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-15337699

RESUMO

BACKGROUND: We performed a series of investigations to test the hypothesis that combining angiogenic gene therapy and cytokine (CK)-induced endothelial progenitor cell mobilization would be superior to either strategy alone for treatment of chronic myocardial ischemia. METHODS AND RESULTS: A swine model of chronic myocardial ischemia and a murine model of acute myocardial infarction were used in this study. In both models, animals were randomly assigned to 1 of 4 treatment groups: Combo group, intramyocardial vascular endothelial growth factor (VEGF)-2 gene transfer plus subcutaneous injection of CKs; VEGF-2, VEGF-2 gene transfer plus saline subcutaneously injected; CK, empty vector transfer plus CKs; and control, empty vector plus subcutaneous saline. Acute myocardial infarction was also induced in wild-type mice 4 weeks after bone marrow transplantation from enhanced green fluorescent protein transgenic mice to permit observation of bone marrow-derived cells in the myocardium after acute myocardial infarction. In chronic myocardial ischemia, combination therapy resulted in superior improvement in all indexes of perfusion and function compared with all other treatment groups. In the bone marrow transplant mice, double immunofluorescent staining revealed that the combination of CK-induced mobilization and local VEGF-2 gene transfer resulted in a significant increase in the number of bone marrow-derived cells incorporating into the neovasculature, indicating that recruitment and/or retention of bone marrow-derived progenitors was enhanced by mobilization and that local VEGF-2 gene transfer can provide signals for recruitment or incorporation of circulating progenitor cells. CONCLUSIONS: Mobilization of endothelial progenitor cells with cytokines potentiates VEGF-2 gene therapy for myocardial ischemia and enhances bone marrow cell incorporation into ischemic myocardium.


Assuntos
Terapia Genética , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas , Infarto do Miocárdio/terapia , Isquemia Miocárdica/terapia , Proteínas Recombinantes/uso terapêutico , Fator de Células-Tronco/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Terapia Combinada , Angiografia Coronária , Técnicas Eletrofisiológicas Cardíacas , Genes Reporter , Vetores Genéticos/administração & dosagem , Vetores Genéticos/uso terapêutico , Proteínas de Fluorescência Verde/análise , Proteínas de Fluorescência Verde/genética , Humanos , Injeções Intralesionais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/patologia , Quimera por Radiação , Distribuição Aleatória , Proteínas Recombinantes de Fusão/fisiologia , Sus scrofa , Ultrassonografia , Fator A de Crescimento do Endotélio Vascular/genética , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia
19.
Circulation ; 110(1): 36-45, 2004 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-15210598

RESUMO

BACKGROUND: Drug-eluting stents represent a useful strategy for the prevention of restenosis using various antiproliferative drugs. These strategies share the liability of impairing endothelial recovery, thereby altering the natural biology of the vessel wall and increasing the associated risk of stent thrombosis. Accordingly, we tested the hypothesis that local delivery via gene-eluting stent of naked plasmid DNA encoding for human vascular endothelial growth factor (VEGF)-2 could achieve similar reductions in neointima formation while accelerating, rather than inhibiting, reendothelialization. METHODS AND RESULTS: phVEGF 2-plasmid (100 or 200 microg per stent)-coated BiodivYsio phosphorylcholine polymer stents versus uncoated stents were deployed in a randomized, blinded fashion in iliac arteries of 40 normocholesterolemic and 16 hypercholesterolemic rabbits. Reendothelialization was nearly complete in the VEGF stent group after 10 days and was significantly greater than in control stents (98.7+/-1% versus 79.0+/-6%, P<0.01). At 3 months, intravascular ultrasound analysis revealed that lumen cross-sectional area (4.2+/-0.4 versus 2.27+/-0.3 mm(2), P<0.001) was significantly greater and percent cross-sectional narrowing was significantly lower (23.4+/-6 versus 51.2+/-10, P<0.001) in VEGF stents compared with control stents implanted in hypercholesterolemic rabbits. Transgene expression was detectable in the vessel wall along with improved functional recovery of stented segments, resulting in a 2.4-fold increase in NO production. CONCLUSIONS: Acceleration of reendothelialization via VEGF-2 gene-eluting stents provides an alternative treatment strategy for the prevention of restenosis. VEGF-2 gene-eluting stents may be considered as a stand-alone or combination therapy.


Assuntos
Arteriopatias Oclusivas/prevenção & controle , Técnicas de Transferência de Genes , Terapia Genética/métodos , Stents , Fatores de Crescimento do Endotélio Vascular/genética , Animais , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/patologia , Terapia Combinada , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Expressão Gênica , Masculino , Óxido Nítrico/biossíntese , Plasmídeos/administração & dosagem , Coelhos , Células-Tronco/citologia , Ultrassonografia , Fatores de Crescimento do Endotélio Vascular/análise
20.
Anat Rec A Discov Mol Cell Evol Biol ; 277(1): 178-203, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14983513

RESUMO

Undifferentiated cells have been identified in the prenatal blastocyst, inner cell mass, and gonadal ridges of rodents and primates, including humans. After isolation these cells express molecular and immunological markers for embryonic cells, capabilities for extended self-renewal, and telomerase activity. When allowed to differentiate, embryonic stem cells express phenotypic markers for tissues of ectodermal, mesodermal, and endodermal origin. When implanted in vivo, undifferentiated noninduced embryonic stem cells formed teratomas. In this report we describe a cell clone isolated from postnatal rat skeletal muscle and derived by repetitive single-cell clonogenic analysis. In the undifferentiated state it consists of very small cells having a high ratio of nucleus to cytoplasm. The clone expresses molecular and immunological markers for embryonic stem cells. It exhibits telomerase activity, which is consistent with its extended capability for self-renewal. When induced to differentiate, it expressed phenotypic markers for tissues of ectodermal, mesodermal, and endodermal origin. The clone was designated as a postnatal pluripotent epiblastic-like stem cell (PPELSC). The undifferentiated clone was transfected with a genomic marker and assayed for alterations in stem cell characteristics. No alterations were noted. The labeled clone, when implanted into heart after injury, incorporated into myocardial tissues undergoing repair. The labeled clone was subjected to directed lineage induction in vitro, resulting in the formation of islet-like structures (ILSs) that secreted insulin in response to a glucose challenge. This study suggests that embryonic-like stem cells are retained within postnatal mammals and have the potential for use in gene therapy and tissue engineering.


Assuntos
Ensaio de Unidades Formadoras de Colônias/métodos , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/fisiologia , Animais , Animais Recém-Nascidos , Masculino , Ratos , Ratos Endogâmicos WF , Ratos Sprague-Dawley , Células-Tronco/citologia , Células-Tronco/fisiologia
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