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1.
Langmuir ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940536

RESUMO

It is known that glow discharges with a water anode inject and form solvated electrons at the plasma-liquid interface, driving a wide variety of reduction reactions. However, in systems with a water cathode, the production and role of solvated electrons are less clear. Here, we present evidence for the direct detection of solvated electrons produced at the interface of an argon plasma and a water cathode via absorption spectroscopy. We further quantify their yield using the dissociative electron attachment of chloroacetate, measuring a yield of 1.04 ± 0.59 electrons per incident ion, corresponding to approximately 100% faradaic efficiency. Additionally, we estimate a yield of 2.09 ± 0.93 hydroxyl radicals per incident ion. Comparison of this yield with other findings in the literature supports that these hydroxyl radicals are likely formed directly in the liquid phase rather than by diffusion from the vapor phase.

3.
Sci Rep ; 9(1): 10377, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31316098

RESUMO

This study describes a new approach to discern early divergence in stem cell lineage progression via temporal dynamics of the cytoskeletal protein, F-actin. The approach involves real-time labeling of human mesenchymal stem cells (MSCs) and longitudinal tracking of the turnover dynamics of a fluorogenic F-actin specific probe, SiR-actin (SA). Cells cultured in media with distinct lineage factors and labeled with SA showed lineage specific reduction in the actin turnover shortly after adipogenic (few minutes) and chondrogenic (3-4 hours) commitment in contrast to osteogenic and basal cultured conditions. Next, composite staining of SA along with the competing F-actin specific fluorescent conjugate, phalloidin, and high-content image analysis of the complementary labels showed clear phenotypic parsing of the sub-populations as early as 1-hour post-induction across all three lineages. Lastly, the potential of SA-based actin turnover analysis to distinguish cellular aging was explored. In-vitro aged cells were found to have reduced actin turnover within 1-hour of simultaneous analysis in comparison to cells of earlier passage. In summary, SiR-actin fluorescent reporter imaging offers a new platform to sensitively monitor emergent lineage phenotypes during differentiation and aging and resolve some of the earliest evident differences in actin turnover dynamics.


Assuntos
Actinas/metabolismo , Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Imagem Óptica/métodos , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Actinas/genética , Adipogenia , Diferenciação Celular/genética , Proliferação de Células , Senescência Celular/fisiologia , Condrogênese , Humanos , Células-Tronco Mesenquimais , Osteogênese , Células-Tronco
4.
Syst Biol Reprod Med ; 59(3): 140-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23278118

RESUMO

Disruption in the normal timing of female puberty, such as in pre-pubertal cancer treatments, can cause abnormal somatic development. We sought to evaluate the impact of cyclophosphamide (CTX) on the somatic, uterine, and ovarian, development of pre-pubertal mice. Pre-pubertal (day 18 of life) C57BL/6J female mice were randomized to receive placebo (group 1A and 1B), 200 mg/kg CTX (group 2A), or 120 mg/kg CTX (group 2B). Mice were euthanized on day 56 (A groups) or 95 (B groups) of life. Body weight and length, uterine and ovarian weight and right femur length and weight were measured, and ovarian insufficiency was assessed. Data were analyzed using ANOVA and t-test. Body weight and length did not differ among groups at time of euthanasia. The femur was shorter and weighed less in mice treated with CTX than in controls. Uterine weight was lower in group 2B than 1B (46.1 mg, 95% CI: 42.9-49.4, vs. 62.2 mg, 95% CI: 58.5-65.8, respectively; p = 0.005) and was lower in mice that developed ovarian insufficiency than in mice that did not (p < 0.05). Ovarian weight was lower in mice treated with CTX, regardless of whether they developed ovarian insufficiency. Even with no observable effect on adult body length and weight, CTX treatment in pre-pubertal mice appears to negatively affect femur, uterine, and ovarian development. However, uterine development seems to be dependent on the hormonal status created by CTX more than on its direct effect.


Assuntos
Antineoplásicos Alquilantes/toxicidade , Ciclofosfamida/toxicidade , Infertilidade Feminina/induzido quimicamente , Ovário/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Útero/efeitos dos fármacos , Fatores Etários , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Fêmur/efeitos dos fármacos , Fêmur/crescimento & desenvolvimento , Hormônio Foliculoestimulante/sangue , Infertilidade Feminina/sangue , Infertilidade Feminina/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/fisiopatologia , Medição de Risco , Fatores de Risco , Desenvolvimento Sexual , Útero/crescimento & desenvolvimento , Útero/metabolismo
5.
J Assist Reprod Genet ; 29(9): 985-95, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22821588

RESUMO

PURPOSE: To appraise the feasibility of current adult medical and surgical techniques for ovarian preservation in pre-pubertal and adolescent girls with cancer. METHODS: Literature search using PubMed and SCOPUS up to February 2012. In addition, the reference lists of selected studies and all identified systematic and narrative reviews were scanned for relevant references. Inclusion criteria were ovarian preservation and cancer. Exclusion criteria were non-English publications, letters, personal communications, and ovarian preservation for conditions other than cancer. RESULTS: Data from the selected publications was interpreted and discussed in the relevant sections. Cryopreservation of ovarian tissue followed by autologous transplant represents the only surgical option available for pre-pubertal girls and adolescents who cannot delay the start of chemotherapy. Few studies report on pre-pubertal and adolescent girls undergoing ovarian preservation surgeries with good harvesting, and no follow-up has been conveyed, to date. Outcomes of ovarian function after ovarian suppression with GnRH-analogs in adults have been controversial and no reports are available for pre-pubertal girls. CONCLUSIONS: Autologous transplantation of cryopreserved ovarian cortex probably represents the best option for preservation of fertility and hormonal function in childhood cancer females; however, future research needs to address the safety of this technique, especially in patients with blood-borne cancers. Ovarian suppression with GnRH-analogs at the time of chemotherapy treatment has not proven to be superior to non-suppression for fertility preservation purposes in adults. Not enough evidence is presently available in childhood cancer patients.


Assuntos
Preservação da Fertilidade/métodos , Hormônio Liberador de Gonadotropina/análogos & derivados , Neoplasias Ovarianas/terapia , Ovário/patologia , Técnicas de Reprodução Assistida/normas , Adolescente , Adulto , Criança , Criopreservação/métodos , Bases de Dados Factuais , Feminino , Fertilidade , Humanos , Infertilidade Feminina/prevenção & controle , Oócitos/citologia , Preservação de Órgãos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Ovário/transplante , Fatores de Risco , Transplante Autólogo
6.
J Oral Maxillofac Surg ; 68(3): 508-14, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20171469

RESUMO

PURPOSE: This study examines the pattern of implant failures reported in a large cohort of patients who received oral bisphosphonate therapy. MATERIALS AND METHODS: A total of 8,572 individuals who received oral bisphosphonate drugs returned a dental survey that obtained information pertaining to implant placement and related complications. Among the 589 individuals reporting dental implants, 16 reported implant failures that were verified by dental records. Implant placement, timing of failure, and bisphosphonate duration were ascertained to determine the characteristics of implant loss in the setting of oral bisphosphonate exposure. RESULTS: Among the 16 patients (all women, aged 70.2 +/- 7.6 yrs) there were 26 implant failures; 8 had failure of 12 implants in the maxilla and 9 had failure of 14 implants in the mandible. Early failure (1 yr after placement) occurred in 10 patients (18 implants); 2 patients had both early and late failures. CONCLUSIONS: Overall, few patients reported implant failures. However, among these, there were more late than early failures and a slightly higher proportion of failures in the mandible versus the maxilla. Further studies should investigate the role of chronic bisphosphonate therapy in implant survival and long-term implant osseointegration.


Assuntos
Alendronato/efeitos adversos , Conservadores da Densidade Óssea/efeitos adversos , Implantação Dentária Endóssea/efeitos adversos , Implantes Dentários/efeitos adversos , Falha de Restauração Dentária , Administração Oral , Idoso , Alendronato/administração & dosagem , Conservadores da Densidade Óssea/administração & dosagem , Feminino , Humanos , Osseointegração/efeitos dos fármacos , Inquéritos e Questionários
7.
J Biomed Mater Res A ; 93(2): 484-92, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19585566

RESUMO

Topical application of beads made from poly(methacrylic acid-co-methyl methacrylate) (45 mol % methacrylic acid, MAA) increased the number of blood vessels and improved 1.5 x 1.5 cm full thickness wound closure in a diabetic mouse (db/db) model. Three groups were compared: MAA beads, control poly(methyl methacrylate) beads (PMMA), and no bead blanks. MAA bead treatment significantly increased percent wound closure at all timepoints (7, 14, and 21 days) with MAA bead-treated wounds almost closed at day 21 (91 +/- 5.4% MAA vs. 79 +/- 3.2% PMMA or 76 +/- 4.8% no beads; p < 0.05). This was consistent with the expected significant increase in vascularity in the MAA group at days 7 and 14. For example at day 14, MAA bead-treated wounds had a vascular density of 22.7 +/- 2.6 vessels/hpf compared with 17.0 +/- 2.0 vessels/hpf in the PMMA bead group (p < 0.05). Epithelial gap and migration measurements suggested that the increased vascularity leads to enhanced epithelial cell migration as a principal means of wound closure. Although studies are underway to elucidate the mechanism of this angiogenic response, the results presented here support the notion that such materials, perhaps in other forms, may be useful in wound care or in other situations where vascularity is to be enhanced without the use of exogenous growth factors.


Assuntos
Diabetes Mellitus Experimental , Metacrilatos , Metilmetacrilato , Neovascularização Fisiológica/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Modelos Animais de Doenças , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Teste de Materiais , Metacrilatos/química , Metacrilatos/farmacologia , Metilmetacrilato/química , Metilmetacrilato/farmacologia , Camundongos , Polimetil Metacrilato/química , Polimetil Metacrilato/farmacologia , Pele/citologia , Pele/efeitos dos fármacos , Pele/patologia
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