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1.
Mol Phylogenet Evol ; 197: 108104, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38750676

RESUMO

Barking geckos (genus Ptenopus) are terrestrial, burrowing lizards endemic to southern Africa, currently with three recognised species. Two species are range-restricted (P. kochi and P. carpi) and display clear differences in substrate preference (soft sand vs. hard gravel). The third and most widespread species, P. garrulus, occurs on a variety of substrates of differing hardness, across potential geographic barriers, and over a steep climatic gradient. Variations in morphology and advertisement calls indicates that P. garrulus may be a species complex. Two subspecies of P. garrulus are currently recognised: P. g. maculatus and P. g. garrulus. To investigate species boundaries, we produced the first comprehensive phylogeny for the genus. We used a novel application of multiple regression on matrices models to assess multiple environmental drivers of diversification, as contrasted to isolation by distance. We show that P. kochi, P. carpi, and P. g. garrulus are valid species, but that P. g. maculatus is a paraphyletic complex of five previously unrecognised taxa. Specialisation onto different substrates was likely the main driver of divergence, with parapatric occurrence of two to four clades occurring at each of the three substrate transition zones identified a priori. The region encompasses diverse bioclimatic regions and potential geographic barriers, and these likely played a role in some divergence events.


Assuntos
Lagartos , Filogenia , Animais , Lagartos/genética , Lagartos/classificação , DNA Mitocondrial/genética , Especiação Genética , Análise de Sequência de DNA , África Austral , Teorema de Bayes , Modelos Genéticos
2.
Genome ; 65(12): 585-604, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36223652

RESUMO

Speciation by polyploidization has been documented to have independently occurred in 12 families of anuran amphibians. Tomopterna tandyi was described as a South African allotetraploid species of sand frogs in the family Pyxicephalidae. Recent taxonomic revisions and new species descriptions in the genus present problems with respect to the evolution of this tetraploid species. Chromosomes, mitochondrial and nuclear gene sequences, isozymes, and male mating calls were examined for T. tandyi and for diploid species of Tomopterna. Mitochondrial sequences confirmed the diploid species, T. adiastola, to be the maternal ancestor that gave rise to the tetraploid about 5 mya. Nuclear sequences and isozymes reveal a complex reticulation of paternal ancestry that may be explained by occasional hybridization of T. tandyi with diploid species of Tompoterna at various times in sympatric populations. Interspecific diploid to tetraploid gene introgression is suspected to have also occurred in Australian and North American tetraploid species of frogs. Diploid to tetraploid introgression is facilitated through triploid hybrids that are more viable than diploid hybrids and produce unreduced triploid eggs.


Assuntos
Tetraploidia , Triploidia , Animais , Masculino , Isoenzimas/genética , Austrália , Anuros/genética , Diploide , Cromossomos , Poliploidia
3.
Int J Radiat Biol ; 98(5): 968-979, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34879217

RESUMO

Purpose: Intentional or accidental exposure of relatively large as well as localized areas of the skin to ionizing radiation can lead to severe damage of many of its cellular components and cutaneous radiation syndrome. Patients can be treated with an invasive surgical procedure coupled with autologous cell therapy. However, this approach remains perfectible, especially for muscle repair. Indeed, a severe underlying muscle defect persists, in particular because of the damage to the satellite cells which ensure muscle regeneration. To overcome these shortcomings, a solution could be to develop new therapeutic strategies based on pharmacological treatments to improve post-irradiation muscle regeneration. In this study, we focus on the Hedgehog signaling pathway as a target, due to its involvement in myogenesis.Materials and methods: To evaluate the benefit of the pro-myogenic Hedgehog signaling pathway modulation, recombinant Sonic Hedgehog (rShh; agonist) or Cyclopamine (antagonist) were used in a stable cell line of mouse C2C12 myoblasts exposed to radiation (X-rays; 5 Gy). Our in vitro studies were carried out under either proliferation or differentiation conditions. Proliferation, migration, survival (apoptosis) and expression of myogenic genes/proteins were evaluated.Results: A high dose of radiation was shown to exert a serious negative impact in our in vitro model of mouse muscle progenitors after irradiation in proliferation or differentiation conditions. Interestingly, Hh pathway stimulation by rShh promotes the proliferation of myoblasts and their survival while its blockade by Cyclopamine significantly increases cell differentiation toward mature myotubes.Conclusion: These data suggest that, after irradiation, the sequence of activation and inhibition of the Hh pathway could allow rescue and proliferation of satellite cells, followed by their differentiation to regenerate new fibers. On the basis of these encouraging in vitro results, the second phase of our study will involve the in vivo validation of this treatment in a new murine model of ultra-localized muscle irradiation.


Assuntos
Proteínas Hedgehog , Mioblastos , Animais , Diferenciação Celular , Proliferação de Células , Proteínas Hedgehog/metabolismo , Humanos , Camundongos , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/metabolismo , Músculos/metabolismo , Mioblastos/metabolismo , Regeneração
4.
Cancer Radiother ; 23(5): 449-465, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31400956

RESUMO

Nowadays, ionizing radiations have numerous applications, especially in medicine for diagnosis and therapy. Pharmacological radioprotection aims at increasing detoxification of free radicals. Radiomitigation aims at improving survival and proliferation of damaged cells. Both strategies are essential research area, as non-contained radiation can lead to harmful effects. Some advances allowing the comprehension of normal tissue injury mechanisms, and the discovery of related predictive biomarkers, have led to developing several highly promising radioprotector or radiomitigator drugs. Next to these drugs, a growing interest does exist for biotherapy in this field, including gene therapy and cell therapy through mesenchymal stem cells. In this review article, we provide an overview of the management of radiation damages to healthy tissues via gene or cell therapy in the context of radiotherapy. The early management aims at preventing the occurrence of these damages before exposure or just after exposure. The late management offers promises in the reversion of constituted late damages following irradiation.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Terapia Genética/métodos , Lesões por Radiação/prevenção & controle , Proteção Radiológica/métodos , Amifostina/uso terapêutico , Animais , Antioxidantes/uso terapêutico , Ensaios Clínicos como Assunto , Fracionamento da Dose de Radiação , Edição de Genes , Vetores Genéticos/uso terapêutico , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Transplante de Células-Tronco Mesenquimais , Camundongos , Oxirredutases/genética , Oxirredutases/uso terapêutico , Lesões por Radiação/etiologia , Lesões por Radiação/terapia , Lesões Experimentais por Radiação/prevenção & controle , Lesões Experimentais por Radiação/terapia , Protetores contra Radiação/farmacologia , Protetores contra Radiação/uso terapêutico , Proteínas Recombinantes/genética , Proteínas Recombinantes/uso terapêutico , Fatores de Tempo
5.
Stem Cells Int ; 2018: 2683969, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29861741

RESUMO

Stem cells are considered as promising tools to repair diverse tissue injuries. Among the different stem cell types, the "olfactory ectomesenchymal stem cells" (OE-MSCs) located in the adult olfactory mucosa stand as one of the best candidates. Here, we evaluated if OE-MSC grafts could decrease memory impairments due to ischemic injury. OE-MSCs were collected from syngeneic F344 rats. After a two-step global cerebral ischemia, inducing hippocampal lesions, learning abilities were evaluated using an olfactory associative discrimination task. Cells were grafted into the hippocampus 5 weeks after injury and animal's learning abilities reassessed. Rats were then sacrificed and the brains collected for immunohistochemical analyses. We observed significant impairments in learning and memory abilities following ischemia. However, 4 weeks after OE-MSC grafts, animals displayed learning and memory performances similar to those of controls, while sham rats did not improve them. Immunohistochemical analyses revealed that grafts promoted neuroblast and glial cell proliferation, which could permit to restore cognitive functions. These results demonstrated, for the first time, that syngeneic transplantations of OE-MSCs in rats can restore cognitive abilities impaired after brain injuries and provide support for the development of clinical studies based on grafts of OE-MSCs in amnesic patients following brain injuries.

6.
Cancer Radiother ; 22(5): 429-437, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29776830

RESUMO

Radiation-induced mucositis is a common toxicity, especially in patients with head and neck cancers. Despite recent technological advances in radiation therapy, such as intensity-modulated radiotherapy, radiation-induced mucositis is still causing treatment disruptions, negatively affecting patients' long and short term quality of life, and impacting medical resources use with economic consequences. The objective of this article was to review the latest updates in the management of radiation-induced mucositis, with a focus on pharmaceutical strategies for the prevention or treatment of mucositis. Although numerous studies analysing the prevention and management of oral radiation-induced mucositis have been conducted, there are still few reliable data to guide daily clinical practice. Furthermore, most of the tested drugs have shown no (anti-inflammatory cytokine, growth factors) or limited (palifermin) effect. Therapies for acute oral mucositis are predominantly focused on improving oral hygiene and providing symptoms control. Although low-level laser therapy proved efficient in preventing radiation-induced oral mucositis in patients with head and neck cancer, this intervention requires equipment and trained medical staff, and is therefore insufficiently developed in clinical routine. New effective pharmacological agents able to prevent or reverse radio-induced mucositis are required.


Assuntos
Mucosite/etiologia , Mucosite/terapia , Radioterapia/efeitos adversos , Amifostina/uso terapêutico , Analgésicos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Benzidamina/uso terapêutico , Suplementos Nutricionais , Fator 7 de Crescimento de Fibroblastos/uso terapêutico , Glutamina/uso terapêutico , Humanos , Terapia com Luz de Baixa Intensidade , Antissépticos Bucais , Higiene Bucal , Protetores contra Radiação/uso terapêutico , Fatores de Risco , Zinco/uso terapêutico
7.
BMC Vet Res ; 14(1): 17, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29343270

RESUMO

BACKGROUND: Stem cell-based therapies are an attractive option to promote regeneration and repair defective tissues and organs. Thanks to their multipotency, high proliferation rate and the lack of major ethical limitations, "olfactory ecto-mesenchymal stem cells" (OE-MSCs) have been described as a promising candidate to treat a variety of damaged tissues. Easily accessible in the nasal cavity of most mammals, these cells are highly suitable for autologous cell-based therapies and do not face issues associated with other stem cells. However, their clinical use in humans and animals is limited due to a lack of preclinical studies on autologous transplantation and because no well-established methods currently exist to cultivate these cells. Here we evaluated the feasibility of collecting, purifying and amplifying OE-MSCs from different mammalian genera with the goal of promoting their interest in veterinary regenerative medicine. Biopsies of olfactory mucosa from eight mammalian genera (mouse, rat, rabbit, sheep, dog, horse, gray mouse lemur and macaque) were collected, using techniques derived from those previously used in humans and rats. The possibility of amplifying these cells and their stemness features and differentiation capability were then evaluated. RESULTS: Biopsies were successfully performed on olfactory mucosa without requiring the sacrifice of the donor animal, except mice. Cell populations were rapidly generated from olfactory mucosa explants. These cells displayed similar key features of their human counterparts: a fibroblastic morphology, a robust expression of nestin, an ability to form spheres and similar expression of surface markers (CD44, CD73). Moreover, most of them also exhibited high proliferation rates and clonogenicity with genus-specific properties. Finally, OE-MSCs also showed the ability to differentiate into mesodermal lineages. CONCLUSIONS: This article describes for the first time how millions of OE-MSCs can be quickly and easily obtained from different mammalian genera through protocols that are well-suited for autologous transplantations. Moreover, their multipotency makes them relevant to evaluate therapeutic application in a wide variety of tissue injury models. This study paves the way for the development of new fundamental and clinical studies based on OE-MSCs transplantation and suggests their interest in veterinary medicine.


Assuntos
Células-Tronco Adultas/citologia , Técnicas Citológicas/métodos , Mucosa Olfatória/citologia , Células-Tronco Adultas/fisiologia , Animais , Biópsia/métodos , Biópsia/veterinária , Técnicas de Cultura de Células , Diferenciação Celular , Mamíferos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Nestina/metabolismo
8.
J Neurotrauma ; 35(15): 1765-1780, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29357739

RESUMO

The transplantation of olfactory ecto-mesenchymal stem cells (OEMSCs) could be a helpful therapeutic strategy for spinal cord repair. Using an acute rat model of high cervical contusion that provokes a persistent hemidiaphragmatic and foreleg paralysis, we evaluated the therapeutic effect of a delayed syngeneic transplantation (two days post-contusion) of OEMSCs within the injured spinal cord. Respiratory function was assessed using diaphragmatic electromyography and neuroelectrophysiological recordings of phrenic nerves (innervating the diaphragm). Locomotor function was evaluated using the ladder-walking locomotor test. Cellular reorganization in the injured area was also studied using immunohistochemical and microscopic techniques. We report a substantial improvement in breathing movements, in activities of the ipsilateral phrenic nerve and ipsilateral diaphragm, and also in locomotor abilities four months post-transplantation with nasal OEMSCs. Moreover, in the grafted spinal cord, axonal disorganization and inflammation were reduced. Some grafted stem cells adopted a neuronal phenotype, and axonal sparing was observed in the injury site. The therapeutic effect on the supraspinal command is presumably because of both neuronal replacements and beneficial paracrine effects on the injury area. Our study provides evidence that nasal OEMSCs could be a first step in clinical application, particularly in patients with reduced breathing/locomotor movements.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Recuperação de Função Fisiológica/fisiologia , Respiração , Traumatismos da Medula Espinal/fisiopatologia , Regeneração da Medula Espinal/fisiologia , Animais , Diafragma/inervação , Mucosa Nasal/citologia , Ratos , Ratos Endogâmicos F344
9.
Cancer Radiother ; 21(6-7): 547-553, 2017 Oct.
Artigo em Francês | MEDLINE | ID: mdl-28888745

RESUMO

The question whether a reirradiation is possible, with either curative of palliative intent, is a frequent issue and a true therapeutic challenge, in particular for a critical organ sensitive to cumulative dose, such as the spinal cord. Preclinical experimental data, based on debatable models that are hardly transferable to patients, suggest that there is a possibility of reirradiation, beyond the classical threshold for dose constraints, taking into account the "time-dose factor". Although the underlying biological mechanisms are however uncertain, scarce clinical data seem to confirm that the tolerance of spinal cord to reirradiation does exist, provided that a particular attention to total dose is given. In the context where modern stereotactic irradiation facilities expand therapeutic perspectives, we review the literature on possibilities of reirradiation, through the example of spinal cord reirradiation.


Assuntos
Dosagem Radioterapêutica , Reirradiação , Medula Espinal/efeitos da radiação , Animais , Humanos , Lesões por Radiação/diagnóstico , Lesões por Radiação/etiologia , Tolerância a Radiação , Radiobiologia , Fatores de Tempo
10.
Neuropharmacology ; 126: 128-141, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28844596

RESUMO

Alzheimer's disease (AD) is the main cause of dementia and a major health issue worldwide. The complexity of the pathology continues to challenge its comprehension and the implementation of effective treatments. In the last decade, a number of possible targets of intervention have been pointed out, among which the stimulation of 5-HT4 receptors (5-HT4Rs) seems very promising. 5-HT4R agonists exert pro-cognitive effects, inhibit amyloid-ß peptide (Aß) production and therefore directly and positively impact AD progression. In the present work, we investigated the effects of RS 67333, a partial 5-HT4R agonist, after chronic administration in the 5xFAD mouse model of AD. 5xFAD male mice and their wild type (WT) male littermates received either RS 67333 or vehicle solution i.p., twice a week, for 2 or 4 months. Cognitive performance was evaluated in a hippocampal-dependent behavioral task, the olfactory tubing maze (OTM). Mice were then sacrificed to evaluate the metabolism of the amyloid precursor protein (APP), amyloidosis and neuroinflammatory processes. No beneficial effects of RS 67333 were observed in 5xFAD mice after 2 months of treatment, while 5xFAD mice treated for 4 months showed better cognitive abilities compared to vehicle-treated 5xFAD mice. The beneficial effects of RS 67333 on learning and memory correlated with the decrease in both amyloid plaque load and neuroinflammation, more specifically in the entorhinal cortex. The most significant improvements in learning and memory and reduction of pathology stigmata were observed after the 4-month administration of RS 67333, demonstrating that treatment duration is important to alleviate amyloidosis and glial reactivity, particularly in the entorhinal cortex. These results confirm the 5-HT4R as a promising target for AD pathogenesis and highlight the need for further investigations to characterize fully the underlying mechanisms of action.


Assuntos
Doença de Alzheimer/prevenção & controle , Precursor de Proteína beta-Amiloide/metabolismo , Compostos de Anilina/administração & dosagem , Córtex Entorrinal/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Piperidinas/administração & dosagem , Agonistas do Receptor 5-HT4 de Serotonina/administração & dosagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Encefalite/metabolismo , Encefalite/prevenção & controle , Córtex Entorrinal/metabolismo , Córtex Entorrinal/patologia , Masculino , Camundongos Transgênicos , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Placa Amiloide/metabolismo , Placa Amiloide/prevenção & controle
11.
Stem Cells Int ; 2017: 1478606, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28698717

RESUMO

Stem cell-based therapies critically rely on selective cell migration toward pathological or injured areas. We previously demonstrated that human olfactory ectomesenchymal stem cells (OE-MSCs), derived from an adult olfactory lamina propria, migrate specifically toward an injured mouse hippocampus after transplantation in the cerebrospinal fluid and promote functional recoveries. However, the mechanisms controlling their recruitment and homing remain elusive. Using an in vitro model of blood-brain barrier (BBB) and secretome analysis, we observed that OE-MSCs produce numerous proteins allowing them to cross the endothelial wall. Then, pan-genomic DNA microarrays identified signaling molecules that lesioned mouse hippocampus overexpressed. Among the most upregulated cytokines, both recombinant SPP1/osteopontin and CCL2/MCP-1 stimulate OE-MSC migration whereas only CCL2 exerts a chemotactic effect. Additionally, OE-MSCs express SPP1 receptors but not the CCL2 cognate receptor, suggesting a CCR2-independent pathway through other CCR receptors. These results confirm that OE-MSCs can be attracted by chemotactic cytokines overexpressed in inflamed areas and demonstrate that CCL2 is an important factor that could promote OE-MSC engraftment, suggesting improvement for future clinical trials.

12.
Bone Marrow Transplant ; 52(10): 1428-1435, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28650455

RESUMO

Unrelated cord blood transplantation (UCBT) after a reduced intensity conditioning regimen (RIC) has extended the use of UCB in elderly patients and those with co-morbidities without an HLA-identical donor, although post-transplant relapse remains a concern in high-risk acute myeloid leukemia (AML) patients. HLA incompatibilities between donor and recipient might enhance the alloreactivity of natural killer (NK) cells after allogeneic hematopoietic stem-cell transplantation (HSCT). We studied the reconstitution of NK cells and KIR-L mismatch in 54 patients who underwent a RIC-UCBT for AML in CR in a prospective phase II clinical trial. After RIC-UCBT, NK cells displayed phenotypic features of both activation and immaturity. Restoration of their polyfunctional capacities depended on the timing of their acquisition of phenotypic markers of maturity. The incidence of treatment-related mortality (TRM) was correlated with low CD16 expression (P=0.043) and high HLA-DR expression (P=0.0008), whereas overall survival was associated with increased frequency of NK-cell degranulation (P=0.001). These features reflect a general impairment of the NK licensing process in HLA-mismatched HSCT and may aid the development of future strategies for selecting optimal UCB units and enhancing immune recovery.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Células Matadoras Naturais/imunologia , Leucemia Mieloide Aguda/imunologia , Recuperação de Função Fisiológica/imunologia , Sistema de Registros , Condicionamento Pré-Transplante , Adulto , Aloenxertos , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida
13.
Radiat Res ; 187(3): 273-286, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28218888

RESUMO

The utility of early-phase (≤5 days) radiation-induced clinical signs and symptoms (e.g., vomiting, diarrhea, erythema and changes in blood cell counts) was examined for the prediction of later occurring acute radiation syndrome (ARS) severity and the development of medical management strategies. Medical treatment protocols for radiation accident victims (METREPOL) was used to grade ARS severities, which were assigned response categories (RCs). Data on individuals (n = 191) with mild (RC1, n = 45), moderate (RC2, n = 19), severe (RC3, n = 20) and fatal (RC4, n = 18) ARS, as well as nonexposed individuals (RC0, n = 89) were generated using either METREPOL (n = 167) or the system for evaluation and archiving of radiation accidents based on case histories (SEARCH) database (n = 24), the latter comprised of real-case descriptions. These data were converted into tables reflecting clinical signs and symptoms, and submitted to eight teams representing five participating countries. The teams were comprised of medical doctors, biologists and pharmacists with subject matter expertise. The tables comprised cumulated clinical data from day 1-3 and day 1-5 postirradiation. While it would have reflected a more realistic scenario to provide the data to the teams over the course of a 3- or 5-day period, the logistics of doing so proved too challenging. In addition, the team members participating in this exercise chose to receive the cumulated reports of day 1-3 and 1-5. The teams were tasked with predicting ARS incidence, ARS severity and the requirement for hospitalization for multiple cases, as well as providing the certainty of their diagnosis. Five of the teams also performed dose estimates. The teams did not employ harmonized methodologies, and the expertise among the members varied, as did the tools used and the means of analyzing the clinical data. The earliest report time was 3 h after the tables were sent to the team members. The majority of cases developing ARS (89.6% ± 3.3 SD) and requiring hospitalization (88.8% ± 4.6 SD) were correctly identified by all teams. Determination of ARS severity was particularly challenging for RC2-3, which was systematically overestimated. However, RC4 was correctly predicted at 94-100% by all teams. RC0 and RC1 ARS severities were more difficult to discriminate. When reported RCs (0-1 and 3-4) were merged, on average 89.6% (±3.3 SD) of all cases could be correctly classified. Comparisons on frequency distributions revealed no statistically significant differences among the following: 1. reported ARS from different teams (P > 0.2); 2. cases generated based on METREPOL or SEARCH (P > 0.5); or 3. results reported at day 3 and 5 postirradiation (P > 0.1). Dose estimates of all teams increased significantly along with ARS severity (P < 0.0001) as well as with dose estimates generated from dicentric chromosomal-aberration measurements available for SEARCH cases (P < 0.0001). In summary, early-phase radiation-induced clinical signs and symptoms proved to be useful for rapid and accurate assessment, with minor limitations, toward predicting life-threatening ARS severity and developing treatment management strategies.


Assuntos
Síndrome Aguda da Radiação/diagnóstico , Incidentes com Feridos em Massa , Síndrome Aguda da Radiação/terapia , Hospitalização , Humanos , Agências Internacionais , Doses de Radiação , Liberação Nociva de Radioativos , Fatores de Tempo
14.
Bone Marrow Transplant ; 51(7): 928-32, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27042842

RESUMO

This report retrospectively analyzed the outcome of 91 patients aged 60 years or older with refractory/relapsed (R/R) classical Hodgkin's lymphoma (cHL) who underwent autologous stem cell transplantation (ASCT) between 1992 and 2013 and were reported to the French Society of Bone Marrow Transplantation and Cell Therapies registry. The median age at transplant was 63 years. The majority of patients exhibited disease chemosensitivity to salvage treatment (57 complete responses, 30 partial responses, 1 progressive disease and 3 unknown). The most frequent conditioning regimen consisted of BCNU, cytarabine, etoposide, melphalan (BEAM) chemotherapy (93%). With a median follow-up of 54 months, 5-year estimates of overall survival (OS) and progression free survival (PFS) for the entire group were 67 and 54%, respectively. Despite the missing data, in univariate analysis, the number of salvage chemotherapy lines (1-2 versus ⩾3) significantly influenced the OS, unlike the other prognostic factors (stage III-IV at relapse, disease status before ASCT and negative positron emission tomography (PET) scan) encountered in younger patients. In spite of its limitations, this retrospective study with a long-term follow-up suggests that ASCT is a valid treatment option for chemosensitive R/R cHL in selected elderly patients, with an acceptable rate of toxicity.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Doença de Hodgkin/terapia , Terapia de Salvação/métodos , Fatores Etários , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Doença de Hodgkin/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Terapia de Salvação/mortalidade , Análise de Sobrevida , Transplante Autólogo
15.
Gynecol Obstet Fertil ; 44(3): 135-40, 2016 Mar.
Artigo em Francês | MEDLINE | ID: mdl-26966036

RESUMO

OBJECTIVES: Uterine myomas are a frequent pathology affecting 20% of women of reproductive age. Myomas induce abnormal uterine bleeding, pelvic pain and increase the risk of infertility and obstetrical complications. Symptomatic sub-mucosal myomas are classically treated by hysteroscopic resection. Simulation is a method of education and training. It could improve quality and security of cares. The aim of this study is to assess the interest of a hysteroscopic simulator for the resection of myoma by novice surgeons. METHODS: Twenty medical students were recruited, in a prospective study, in august 2014. The virtual-reality simulator VirtaMed HystSim™ (VirtaMed AG, Zurich, Switzerland) was used to perform the hysteroscopic training. All students received a short demonstration of myoma resection. The practice consists of a submucous myoma type 0 resection. The procedure and the evaluation were performed before and after a specific training in hysteroscopic resection of sixty minutes long. The main outcome criteria were time for the resection before and after training. The second criteria were fluid quantity used, number of contact between optic and uterine cavity and uterine perforation. RESULTS: Twenty students aged from 22 to 24 years were included. The time for the procedure was significantly reduced after training (170s versus 335s, P<0.01). There is the same for fluid quantity used (335 mL versus 717mL, P<0.01) and the number of contact between optic and uterine cavity (0.2 contact versus 3, P=0.012). No perforation occurred in the simulation. CONCLUSION: The results suggest that hysteroscopic simulator enhances and facilitates hysteroscopic resection for novice surgeons.


Assuntos
Histeroscopia/educação , Leiomioma/cirurgia , Treinamento por Simulação/métodos , Miomectomia Uterina/educação , Neoplasias Uterinas/cirurgia , Educação Médica/métodos , Feminino , Humanos , Masculino , Estudos Prospectivos , Estudantes de Medicina , Miomectomia Uterina/métodos , Adulto Jovem
16.
Front Mol Neurosci ; 9: 163, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28119565

RESUMO

We previously reported that deficiency of membrane-type five matrix metalloproteinase (MT5-MMP) prevents amyloid pathology in the cortex and hippocampus of 5xFAD mice, and ameliorates the functional outcome. We have now investigated whether the integrity of another important area affected in Alzheimer's disease (AD), the frontal cortex, was also preserved upon MT5-MMP deficiency in 4-month old mice at prodromal stages of the pathology. We used the olfactory H-maze (OHM) to show that learning impairment associated with dysfunctions of the frontal cortex in 5xFAD was prevented in bigenic 5xFAD/MT5-MMP-/- mice. The latter exhibited concomitant drastic reductions of amyloid beta peptide (Aß) assemblies (soluble, oligomeric and fibrillary) and its immediate precursor, C99. Simultaneously, astrocyte reactivity and tumor necrosis factor alpha (TNF-α) levels were also lowered. Moreover, MT5-MMP deficiency induced a decrease in N-terminal soluble fragments of amyloid precursor protein (APP), including soluble APPα (sAPPα), sAPPß and the MT5-MMP-linked fragment of 95 kDa, sAPP95. However, the lack of MT5-MMP did not affect the activity of ß- and γ-secretases. In cultured HEKswe cells, transiently expressed MT5-MMP localized to early endosomes and increased the content of APP and Aß40 in these organelles, as well as Aß levels in cell supernatants. This is the first evidence that the pro-amyloidogenic features of MT5-MMP lie, at least in part, on the ability of the proteinase to promote trafficking into one of the amyloidogenic subcellular loci. Together, our data further support the pathogenic role of MT5-MMP in AD and that its inhibition improves the functional and pathological outcomes, in this case in the frontal cortex. These data also support the idea that MT5-MMP could become a novel therapeutic target in AD.

17.
Blood Cancer J ; 5: e345, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26314987

RESUMO

Monoclonal gammopathies of undetermined significance (MGUS) have been shown to be associated with an increased risk of fractures. This study describes prospectively the bone status of MGUS patients and determines the factors associated with vertebral fracture. We included prospectively 201 patients with MGUS, incidentally discovered, and with no known history of osteoporosis: mean age 66.6±12.5 years, 48.3% women, 51.7% immunoglobulin G (IgG), 33.3% IgM and 10.4% IgA. Light chain was kappa in 64.2% patients. All patients had spinal radiographs and bone mineral density measurement in addition to gammopathy assessment. At least one prevalent non-traumatic vertebral fracture was discovered in 18.4% patients and equally distributed between men and women. Fractured patients were older, had a lower bone density and had also more frequently a lambda light chain isotype. Compared with patients with κ light chain, the odds ratio of being fractured for patients with λ light chain was 4.32 (95% confidence interval 1.80-11.16; P=0.002). These results suggest a high prevalence of non-traumatic vertebral fractures in MGUS associated with lambda light chain isotype and not only explained by low bone density.


Assuntos
Gamopatia Monoclonal de Significância Indeterminada/complicações , Fraturas da Coluna Vertebral/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gamopatia Monoclonal de Significância Indeterminada/epidemiologia , Análise Multivariada , Prevalência , Estudos Prospectivos , Radiografia , Fatores de Risco , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/epidemiologia
18.
J Arthroplasty ; 30(10): 1777-80, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25971533

RESUMO

UNLABELLED: Hydroxyapatite (HA) is commonly used on femoral stems to assist in osseous integration but there is limited evidence of the benefit it provides. We report a prospective comparison of 117 and 102 patients receiving either porous or HA coated sleeves respectively. Patients were evaluated at mean of 12.5 years in the porous and 13.7 years in the HA groups. The mean Harris Hip Score was 94.7 and 94.5 in the porous and HA groups respectively. One porous and 2 HA stems required revision. This study demonstrates that there is no long-term advantage to using an HA coating on the sleeve of this modular stem and confirms excellent long-term results for the SROM stem in a primary arthroplasty setting. LEVEL OF EVIDENCE: II (prospective cohort study).


Assuntos
Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Materiais Revestidos Biocompatíveis/química , Durapatita/química , Fêmur/cirurgia , Prótese de Quadril , Desenho de Prótese , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Porosidade , Estudos Prospectivos , Falha de Prótese , Reoperação/instrumentação , Fatores de Tempo , Resultado do Tratamento
19.
Leukemia ; 29(7): 1496-501, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25676424

RESUMO

Allogeneic hematopoietic stem cell transplantation (HSCT) is considered the only a curative treatment in patients with higher risk myelodysplastic syndrome (MDS), although demethylating agents (DMA) have been reported to improve survival. The advantage of HSCT over other treatment comes from retrospective studies and the aim of the current study was to prospectively test this hypothesis, analyzing in particular patients from the pre-transplant period to avoid the selection bias of performing transplantation. This study was conducted to compare overall survival in MDS patients candidates to transplantation according to donor availability. The majority of patients (76%) received a treatment with DMA after registration, 69% had a human leukocyte antigen (HLA)-identical donor, 70% of whom were transplanted. Baseline patient and disease characteristics were similar according to donor availability. Four-year overall survival was significantly better in patients with an HLA matched donor (37%) compared to patients without donor (15%). There was also evidence that this overall survival advantage was because of transplantation. Mortality risk was decreased after transplantation but it became significant only after the second year post transplant, because of early transplant-related mortality. Our results appear to justify, in higher risk MDS, a transplantation approach in all potential candidates who have an HLA identical donor.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígenos HLA/imunologia , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/terapia , Transplante de Células-Tronco , Idoso , Terapia Combinada , Feminino , Seguimentos , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Condicionamento Pré-Transplante , Transplante Homólogo
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