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1.
Int J Gynecol Cancer ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858104

RESUMO

In the last decade, we have witnessed important advances in novel therapeutics in the management of gynecologic cancers. These studies have built on the findings from preexisting data and have provided incremental contributions leading to changes that have not only impacted the accuracy of cancer detection and its metastatic components but also led to improvements in oncologic outcomes and quality of life. Key landmark trials have changed the standard of care in cervix, uterine, and ovarian cancer. A number of these have been controversial and have generated significant debate among gynecologic oncologists. The main objective of this review was to provide an overview on each of these trials as a reference for immediate and consolidated access to the study aims, methodology, results, and conclusion.

3.
Diagnostics (Basel) ; 13(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36980492

RESUMO

BACKGROUND: Uterine adenomyosis is an increasingly frequent disorder. Our study aimed to demonstrate the presence of obstetric complications in the population affected by this condition to demonstrate the need for follow-up in high-risk obstetric units. MATERIAL AND METHODS: The data for the study were obtained from TriNetX, LLC, between 2010 and 2020. The outcomes analyzed were intrauterine growth restriction (IUGR), preterm delivery, cesarean delivery, hypertension, abruption placentae, and spontaneous abortion. Seven thousand six hundred and eight patients were included in the cohort of pregnant patients with adenomyosis, and 566,153 women in the cohort of pregnant patients without any history of endometriosis. RESULTS: Upon calculating the total risk of presenting any of these problems during pregnancy, we obtained an OR = 1.521, implying that a pregnancy with adenomyosis was 52.1% more likely to present some complication. We found: IUGR OR = 1.257 (95% CI: 1.064-1.485) (p = 0.007); preterm delivery OR = 1.422 (95% CI: 1.264-1.600) (p = 0.0001); cesarean delivery OR = 1.099 (95% CI: 1.002-1.205) (p = 0.046); hypertensive disorders OR = 1.177 (95% CI: 1.076-1.288) (p = 0.0001); abruption placentae OR = 1.197 (95% CI: 1.008-1.422) (p = 0.040), and spontaneous abortion OR = 1.529 (95% CI: 1.360-1.718) (p = 0.0001). CONCLUSION: We conclude that the review carried out and the data we obtained on increased risk provide sufficient evidence to recommend that patients with adenomyosis should be managed in obstetric high-risk units.

4.
Nanomaterials (Basel) ; 9(1)2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-30654537

RESUMO

Three different types of lignin (kraft, organosolv and phosphoric acid lignin) were characterized and tested as precursors of electrospun nanofibers. Polyethylene oxide (PEO) was added as a plasticizer and dimethyl formamide (DMF) employed as a solvent. It was found that the molecular weight of lignin was the key parameter to understand the differences of the mechanical stability of the resultant fiber mats. In the case of kraft lignin (KL), the influence of some changes in the synthetic process was also tested: applied voltage, pretreatment in air or not, and the addition of a small amount of Ketjen black. After pyrolysis in nitrogen flow, the obtained carbon nanofibers (CNFs) were characterized by different techniques to analyze their differences in morphology and surface chemistry. Vanadium electrochemistry in 3M sulfuric acid was used to evaluate the different CNFs. All fibers allowed electrochemical reactions, but we observed that the oxidation of V(II) to V(III) was very sensitive to the nature of the raw material. Materials prepared from kraft and phosphorus lignin showed the best performances. Nevertheless, when 1 wt.% of Ketjen black was added to KL during the electrospinning, the electrochemical performance of the sample was significantly improved and all targeted reactions for an all-vanadium redox flow battery were observed. Therefore, in this work, we demonstrated that CNFs obtained by the electrospinning of lignin can be employed as electrodes for vanadium electrochemistry, and their properties can be tuned to improve their electrochemical properties.

5.
Sleep Health ; 4(6): 565-571, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30442326

RESUMO

OBJECTIVE: This study investigated predictors of poor sleep quality among American and Bolivian students. DESIGN: A cross-sectional survey was designed and administered to undergraduate university students. SETTING AND PARTICIPANTS: Psychology classes from 2 public universities (Texas, USA, and Bolivia) were convenience sampled (n = 80 American students; 60 Bolivian students). MEASUREMENTS: We used a sleep quality index and the Perceived Stress Scale. We added questions concerning worldview, sleep hygiene, sleep deficiency, health behaviors, and demographics. RESULTS: Five variables predicted poor sleep quality: perceived stress, sleep hygiene, sleep deficiency, worldview, and site. Greater stress positively associated with poorer sleep in both cultures. Yet, Bolivian students reported significantly more stress than American students but experienced significantly better sleep quality. Worldview, a measure of optimism or pessimism about the world, negatively associated with sleep quality in both cultures. CONCLUSION: Three variables that predict sleep quality (worldview, sleep hygiene, and sleep deficiency) did not differ significantly between countries. Only perceived stress differed by country but contrary to the predicted direction. Thus, this work reveals new avenues for future work to the investigation of sleep in different cultures. Lastly, we offer recommendations to ameliorate poor sleep in university students.


Assuntos
Comparação Transcultural , Sono , Estresse Psicológico/psicologia , Estudantes/psicologia , Adulto , Bolívia , Estudos Transversais , Feminino , Humanos , Masculino , Otimismo/psicologia , Percepção , Pessimismo/psicologia , Higiene do Sono , Estudantes/estatística & dados numéricos , Fatores de Tempo , Estados Unidos , Universidades , Adulto Jovem
6.
Nanomaterials (Basel) ; 8(4)2018 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-29690602

RESUMO

A series of carbon aerogels doped with iron, cobalt and nickel have been prepared. Metal nanoparticles very well dispersed into the carbon matrix catalyze the formation of graphitic clusters around them. Samples with different Ni content are obtained to test the influence of the metal loading. All aerogels have been characterized to analyze their textural properties, surface chemistry and crystal structures. These metal-doped aerogels have a very well-developed porosity, making their mesoporosity remarkable. Ni-doped aerogels are the ones with the largest surface area and the smallest graphitization. They also present larger mesopore volumes than Co- and Fe-doped aerogels. These materials are tested as electro-catalysts for the oxygen reduction reaction. Results show a clear and strong influence of the carbonaceous structure on the whole electro-catalytic behavior of the aerogels. Regarding the type of metal doping, aerogel doped with Co is the most active one, followed by Ni- and Fe-doped aerogels, respectively. As the Ni content is larger, the kinetic current densities increase. Comparatively, among the different doping metals, the results obtained with Ni are especially remarkable.

7.
Microsc Microanal ; 22(4): 865-77, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27487730

RESUMO

The acquisition of neuroendocrine (NE) characteristics by prostate cancer (PC) cells relates to tumor progression and hormone resistance. PC cells may survive and function in androgen-deprived environments, where they could establish paracrine signaling networks, providing stimuli for the propagation of local carcinoma cells. We previously demonstrated, using electron probe X-ray microanalysis (EPXMA), in LNCaP, PC-3, and Du 145 cell lines that apoptosis is associated with intracellular elemental changes, and that the NE secretory products, bombesin and calcitonin, inhibit etoposide-induced apoptosis, as well as some of these elemental changes. In this study, LNCaP cells were induced in vitro to transdifferentiate under androgen deprivation, to mimic the role of NE cells in the apoptotic activity of transdifferentiated androgen-dependent PC cells. Changes in intracellular ion content associated with apoptosis, assessed by EPXMA, demonstrate that the transdifferentiated LNCaP cells are resistant to etoposide-induced apoptosis and also to the etoposide-induced elemental changes. The aggressive malignant potential of PC with neuroendocrine differentiation, associated with hormonal independence, is partly because of the ability that most NE tumor cells have to escape apoptosis, which can enhance the malignant properties of tumor cells and may have therapeutic implications as tumor cells are usually resistant to cytotoxic drugs as etoposide.


Assuntos
Androgênios/metabolismo , Apoptose , Carcinoma/patologia , Neoplasias da Próstata/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Humanos , Masculino , Células Neuroendócrinas/citologia
8.
Biomed Res Int ; 2014: 253590, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24883304

RESUMO

The possibility of tailoring membrane surfaces with osteoconductive potential, in particular in biodegradable devices, to create modified biomaterials that stimulate osteoblast response should make them more suitable for clinical use, hopefully enhancing bone regeneration. Bioactive inorganic materials, such as silica, have been suggested to improve the bioactivity of synthetic biopolymers. An in vitro study on HOB human osteoblasts was performed to assess biocompatibility and bioactivity of SiO2 functionalized poly(lactide-co-glycolide) (PLGA) membranes, prior to clinical use. A 15 nm SiO2 layer was deposited by plasma enhanced chemical vapour deposition (PECVD), onto a resorbable PLGA membrane. Samples were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, and infrared spectroscopy (FT-IR). HOB cells were seeded on sterilized test surfaces where cell morphology, spreading, actin cytoskeletal organization, and focal adhesion expression were assessed. As proved by the FT-IR analysis of samples, the deposition by PECVD of the SiO2 onto the PLGA membrane did not alter the composition and other characteristics of the organic membrane. A temporal and spatial reorganization of cytoskeleton and focal adhesions and morphological changes in response to SiO2 nanolayer were identified in our model. The novedous SiO2 deposition method is compatible with the standard sterilization protocols and reveals as a valuable tool to increase bioactivity of resorbable PLGA membranes.


Assuntos
Biopolímeros/química , Regeneração Óssea , Dióxido de Silício/química , Adesão Celular/efeitos dos fármacos , Humanos , Osteoblastos/efeitos dos fármacos , Poliglactina 910/química , Dióxido de Silício/síntese química , Dióxido de Silício/uso terapêutico , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
9.
Materials (Basel) ; 7(3): 1687-1708, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-28788538

RESUMO

New biomaterials for Guided Bone Regeneration (GBR), both resorbable and non-resorbable, are being developed to stimulate bone tissue formation. Thus, the in vitro study of cell behavior towards material surface properties turns a prerequisite to assess both biocompatibility and bioactivity of any material intended to be used for clinical purposes. For this purpose, we have developed in vitro studies on normal human osteoblasts (HOB®) HOB® osteoblasts grown on a resorbable Poly (lactide-co-glycolide) (PLGA) membrane foil functionalized by a very thin film (around 15 nm) of TiO2 (i.e., TiO2/PLGA membranes), designed to be used as barrier membrane. To avoid any alteration of the membranes, the titanium films were deposited at room temperature in one step by plasma enhanced chemical vapour deposition. Characterization of the functionalized membranes proved that the thin titanium layer completely covers the PLGA foils that remains practically unmodified in their interior after the deposition process and stands the standard sterilization protocols. Both morphological changes and cytoskeletal reorganization, together with the focal adhesion development observed in HOB osteoblasts, significantly related to TiO2 treated PLGA in which the Ti deposition method described has revealed to be a valuable tool to increase bioactivity of PLGA membranes, by combining cell nanotopography cues with the incorporation of bioactive factors.

10.
J Biomed Mater Res A ; 101(4): 1026-35, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22965473

RESUMO

We have studied the effect of the UV induced superhydrophilic wetting of TiO(2) thin films on the osteoblasts cell adhesion and cytoskeletal organization on its surface. To assess any effect of the photo-catalytic removal of adventitious carbon as a factor for the enhancement of the osteoblast development, 100 nm amorphous TiO(2) thin layers were deposited on polyethylene terephthalate (PET), a substrate well known for its poor adhesion and limited wettability and biocompatibility. The TiO(2) /PET materials were characterized by X-ray photoelectron spectroscopy, and atomic force microscopy and their wetting behavior under light illumination studied by the sessile drop method. The amorphous TiO(2) thin films showed a very poor photo-catalytic activity even if becoming superhydrophilic after illumination. The illuminated samples recovered partially its initial hydrophobic state only after their storage in the dark for more than 20 days. Osteoblasts (HOB) were seeded both on bare PET and on TiO(2) /PET samples immediately after illumination and also after four weeks storage in darkness. Cell attachment was much more efficient on the immediately illuminated TiO(2)/PET samples, with development of focal adhesions and cell traction forces. Although we cannot completely discard some photo-catalytic carbon removal as a factor contributing to this cell enhanced attachment, our photodegradation experiments on amorphous TiO(2) are conclusive to dismiss this effect as the major cause for this behavior.


Assuntos
Luz , Osteoblastos/metabolismo , Polietilenotereftalatos/química , Titânio/química , Adesão Celular/efeitos da radiação , Linhagem Celular , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Humanos , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Osteoblastos/ultraestrutura
11.
Histol Histopathol ; 24(10): 1275-86, 2009 10.
Artigo em Inglês | MEDLINE | ID: mdl-19688695

RESUMO

Osseointegration of implants is crucial for the long-term success of oral implants. The periimplant bone formation by osteoblasts is strongly dependent on the local mechanical environment in the interface zone. Robust demands for energy are placed on osteoblasts during the adhesion process to solid surfaces, and mitochondria are capital organelles in the production of most of the ATP needed for the process. We have assessed the relationship between osteoblast differentiation and mitochondrial bioenergetics in living cells grown on two different titanium surfaces, in order to provide valuable information for the design of material surfaces required for the development of the most appropriate osteogenic surface for osteoblastic anchorage. Combined backscattered and fluorescence confocal microscopy showed that in flat cells grown on a machined surface, highly energized mitochondria were distributed along the cell body. In contrast, cells grown on the rough surface emitted long protrusions in search of surface roughness, with actin stress fibers clearly polarized and highly energized mitochondria clustered at focal adhesion sites. This report using normal human osteoblastic cells indicates that these cells are especially sensitive to surface cues through energy production that enhances the necessary adhesion required for a successful osseointegration.


Assuntos
Implantes Dentários , Metabolismo Energético , Mitocôndrias/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Adesão Celular/fisiologia , Diferenciação Celular , Células Cultivadas , Humanos , Potencial da Membrana Mitocondrial/fisiologia , Osseointegração , Propriedades de Superfície , Titânio/metabolismo
12.
J Biochem ; 145(1): 21-30, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18849572

RESUMO

To dissect the rat receptor for advanced glycation end products (RAGE) subcellular distribution and trafficking in eukaryotic cells, an expression system coding for a fusion protein between the RAGE and an enhanced green fluorescent protein (EGFP) has been used. The RAGE-EGFP protein is expressed at the plasma membrane of CHO-k1 and Neuro-2a (N2a) cells and retains the capacity to bind Texas Red-labelled advanced glycation end products (AGEs). AGEs addition to the cell cultures induced a change in the subcellular distribution of the fluorescent RAGE-EGFP protein compatible with an internalization of the AGEs-RAGE complex. Furthermore, while N2a cells expressing the RAGE-EGFP showed an increase in ERK1/2 phosphorylation and NF-kappaB DNA binding in response to AGEs, pre-incubation with dansyl-cadaverine or phenylarsine oxide, inhibitors of receptors internalization, blocked the activation of ERKs and other intracellular responses mediated by AGEs. These results suggest that internalization plays a key role in the signal transduction mediated by RAGE.


Assuntos
Receptores Imunológicos/análise , Receptores Imunológicos/metabolismo , Animais , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Proteínas de Fluorescência Verde/metabolismo , Microscopia Confocal , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Ratos , Receptor para Produtos Finais de Glicação Avançada
13.
Mol Cancer Ther ; 6(4): 1292-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17431107

RESUMO

Neuroendocrine secretory products and their interactions with epithelial prostate cells are currently under investigation in order to understand their significance in the pathogenesis, prognosis, and therapy of prostate carcinoma. These neuropeptides have the potential to disrupt the balance between cell death and cell growth in the tumor. Our research was based on the role of bombesin in modulating the mitochondrial membrane potential (Delta psi(m)) in cell death induced by etoposide on PC-3 cells. Cells were cultured and stained with 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1). At low membrane potentials, JC-1 produces a green fluorescence, and at high membrane potentials, it forms "J aggregates" with red fluorescence. Cells were examined in a confocal microscope. For quantitative analyses, regions of interest were selected. The size, number of pixels, and ratios between fluorescence intensity in the red and green channels in each region of interest were calculated. The loss of Delta psi(m) in etoposide-treated PC-3 cells was prevented by bombesin. The quantitative analysis of JC-1-stained cells revealed a significant decrease in the red (high Delta psi(m)) to green (low Delta psi(m)) ratio in etoposide-treated cells when compared with control cells, which was restored in the presence of bombesin (P < 0.00001). The interaction between treatments and area (P = 0.0002) was highly significant, and confirms that PC-3 cells keep their apoptosis machinery, showing an apoptotic volume decrease in response to etoposide. The protection by bombesin occurs by inhibition of apoptosis and maintenance of mitochondrial integrity. New therapeutic protocols and trials need to be developed to test drugs acting through the neutralization of antiapoptotic intracellular pathways mediated by neuroendocrine hormones.


Assuntos
Apoptose/efeitos dos fármacos , Bombesina/farmacologia , Etoposídeo/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Neoplasias da Próstata/patologia , Análise de Variância , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Intervalos de Confiança , Humanos , Cinética , Masculino , Microscopia Confocal , Mitocôndrias/efeitos dos fármacos
14.
Health Promot Int ; 22(1): 37-43, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17202196

RESUMO

This study demonstrates that Bolivian long distance truck drivers are a high risk population of HIV infection and transmission, supporting other global studies involving truck drivers and their high risk. The aims of this investigation were to estimate the prevalence of high risk behaviors and to identify predictors of condom use in this population. Analysis was completed on survey results from 246 male truckers (aged 18-67). About one in three of the truck drivers (30%) reported having had a sexually transmitted infection sometime in their past. More than half (56%) reported having sex with casual partners. Other risks involved unprotected anal sex. Age and two social cognitive constructs (outcome expectations and perceived social norms) predicted condom use from logistic regression analysis. The authors discuss the need for expanded HIV/sexually transmitted infection prevention programs that incorporate social cognitions.


Assuntos
Preservativos/estatística & dados numéricos , Veículos Automotores , Percepção Social , Adolescente , Adulto , Fatores Etários , Idoso , Bolívia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Risco , Infecções Sexualmente Transmissíveis/prevenção & controle , Meio Social
15.
Cancer ; 94(2): 368-77, 2002 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11900223

RESUMO

BACKGROUND: Etoposide-induced apoptosis in prostate carcinoma cells is associated with changes in the elemental content of the cells. The authors previously reported that calcitonin and bombesin inhibited etoposide-induced apoptosis in these cells. In the current study, the authors investigated whether these neuropeptides block the etoposide-induced changes in elemental content. METHODS: Cells from the PC-3 and Du 145 prostate carcinoma cell lines were grown either on solid substrates or on thin plastic films on titanium electron microscopy grids, and they were exposed to etoposide for 48 hours in the absence or presence of calcitonin and bombesin. After the exposure, the cells were frozen and freeze dried, and their elemental content was analyzed by energy-dispersive X-ray microanalysis in both in the scanning electron microscope and the scanning transmission electron microscope. RESULTS: Etoposide treatment consistently induced an increase in the cellular Na concentration and a decrease in the cellular K concentration, resulting in a marked increase of the Na/K ratio and also an increase in the phosphorus:sulphur (P/S) ratio. Both bombesin and calcitonin inhibited the etoposide-induced changes in the cellular Na/K ratio, and calcitonin, but not bombesin, inhibited the changes in the P/S ratio. No significant elemental changes were found with bombesin or calcitonin alone. CONCLUSIONS: The neuropeptides bombesin and calcitonin, which inhibited etoposide-induced apoptosis, also inhibited the etoposide-induced elemental changes in prostate carcinoma cells. This important fact strengthens the link between apoptosis and changes in the intracellular elemental content. This correlation provides an objective basis for the study of neuropeptide target points and may be helpful for alternative therapeutic protocols using neuropeptide inhibitors in the treatment of patients with advanced prostatic carcinoma.


Assuntos
Apoptose/efeitos dos fármacos , Bombesina/farmacologia , Calcitonina/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Absorciometria de Fóton , Antineoplásicos Fitogênicos/farmacologia , Cálcio/metabolismo , Divisão Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/farmacologia , Citometria de Fluxo , Formazans , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Fósforo/metabolismo , Potássio/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Sódio/metabolismo , Enxofre/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/ultraestrutura
16.
Invest. educ. enferm ; 15(2): 71-81, sept. 1997. tab
Artigo em Espanhol | LILACS, BDENF - Enfermagem | ID: lil-354072

RESUMO

En la presente investigación se estudiaron a través de una encuesta los hábitos de consumo de tabaco de 282 estudiantes de medicina de una universidad pública ubicada en el Distrito Federal de México. Los índices de tabaquismo entre hombres (52,4 por ciento) y mujeres (26,7 por ciento) fueron significativamente diferentes p <0.001. El estudio puso en evidencia una alta prevalencia de tabaquismo entre estudiantes de medicina hombres y un bajo interés de las alumnas mujeres por dejar de fumar. La dependencia nicotínica en los sujetos estudiados mediante la escala de Fagerström modificada fue la siguiente: en hombres un promedio de 4,6 y desviación estándar de 2,4; en mujeres un promedio de 4,8 y desviación estándar de 2,1. La diferencia entre hombres y mujeres no fue significativa. Los modelos familiares respecto al consumo de tabaco fueron más importantes en la adquisición y conservación del hábito de fumar en mujeres. Se concluye entonces que es necesario seguir realizando estudios tanto cuantitativos como cualitativos desde una perspectiva de género en este tipo de poblaciones. Esta aproximación metodológica permitirá diseñar programas educativos que no se centren exclusivamente en la transmisión de mensajes que enfaticen la asociación tabaquismo riesgos para la salud y que tomen en cuenta la compleja red de motivaciones que subyacen a este tipo de hábitos particularmente la necesidad de manejar el estrés que producen las actividades que desempeñan los profesionales del área de la salud.


Assuntos
Fumar , México
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