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1.
Artículo en Inglés | MEDLINE | ID: mdl-38063565

RESUMEN

During the pandemic confinement, the WHO changed the term "social distancing" to "physical distancing", to help people deal with the lack of social contact. As a result, there was an increase in mental health problems, including insomnia and stress, with a negative impact on cardiovascular health. The objective of this research was to identify the association between insomnia and stress and cardiovascular risk (CVR) during the pandemic in a sample of the general population in Mexico; the participants were chosen using the non-probabilistic method. The data were obtained from an online questionnaire about medical histories focused on cardiovascular risk, according to the Official Mexican Standards and Regulations for patients' clinical records, NOM-004-SSA3-2012, along with an index for the severity of insomnia, measured with a seven-item guide, and an instrument to measure stress. The data were analyzed with descriptive statistics for several different variables: sociodemographics, stress, insomnia, and cardiovascular risk. Cardiovascular risk was compared to insomnia and stress variables, which led to statistically significant differences and correlations between the variables. Participants were divided into four groups with respect to CVR, from low to very high CVR. This research demonstrated that women were more susceptible to stress and cardiovascular risk. However, stress was a more major indicator of CVR than insomnia, but in the high and very high CVR groups, insomnia contributed along with stress; coping strategies reduced the risk in the high CVR group but did not function as expected with respect to reducing risk in the very high CVR group. These findings suggest that sleep patterns and mental health alterations present during the pandemic may persist even when the pandemic was declared as having ended and may contribute to increases in cardiovascular risk in the long-term.


Asunto(s)
COVID-19 , Enfermedades Cardiovasculares , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Femenino , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Enfermedades Cardiovasculares/epidemiología , México/epidemiología , COVID-19/epidemiología , Factores de Riesgo , Factores de Riesgo de Enfermedad Cardiaca
2.
Toxics ; 11(10)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37888694

RESUMEN

Chlorophenols (CPs) have been extensively used worldwide as a treatment to prevent the growth and proliferation of different microorganisms, mainly in the wood and farm industries. Chlorine has been used for water disinfection, and phenol groups are water contaminants; these two groups can react with each other to form species such as 2,4-dichlorophenol (2,4-DCP). 2,4-DCP is still used as an herbicide in many countries such as Mexico. CPs have been largely analyzed, like bisphenol A, for their probable endocrine-disrupting effects in humans and aquatic animals. We still do not understand whether these endocrine responses can be manifested as an impairment in sexual behavior in rodents. With the present toxicology study, the endocrine-disrupting effects of 2,4-DCP on male sexual behavior were investigated. Sexually naïve male Wistar rats were used to assess the endocrine-disrupting effects of 2,4-DCP. The rats were divided into two groups: one control group and one experimental group that was administered 1.25 mg/day of 2,4-DCP for 45 days. After completing treatment, the male sexual behavior of the rats was evaluated. The results of this investigation demonstrated that 2,4-DCP affected male sexual behavior. A decrease in mount latency, intromission latency, and post ejaculation period compared with the control animals was found.

3.
Polymers (Basel) ; 12(4)2020 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-32283702

RESUMEN

In this study, new polyurethanes (PUs) were prepared by using inulin and polycaprolactone as polyols. Their structure and morphology were determined by Fourier transform infrared spectroscopy (FTIR), Raman dispersive spectroscopy, Nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR), and scanning electron microscopy (SEM), whereas their mechanical properties were evaluated by a universal testing machine. Additionally, their water uptake, swelling behavior, and degradation were evaluated to be used as drug delivery carriers. Therefore, an anti-cancer drug was loaded to these PUs with 25% of loading efficiency and its release behavior was studied using different theoretical models to unveil its mechanism. Finally, the ability of the new PUs to be used as a clip marker in breast biopsy was evaluated. The results clearly demonstrate that these PUs are safe and can be used as intelligent drug release matrices for targeted drug delivery and exhibits positive results to be used for clip marker and in general for breast cancer applications.

4.
Polymers (Basel) ; 10(12)2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30961232

RESUMEN

Strength and biocompatibility of composite materials (using a polymer matrix) are used in medicine for various devices such as prostheses and marker clips (biomarkers). Marker clips indicate the site of a lesion in the body, specifically for breast cancer diagnosis or treatment. In general, marker clips are made of steel or titanium, but lately, materials containing biodegradable polymers had been proposed. Our hypothesis is that a copolymer of polylactic acid and poly(ε-caprolactone) (PLA-PCL) could be used as marker clip material. After evaluating different polymer rates performance, metallic nanoparticles (NPs) were included to enhance the stability of the best copolymer and a marker clip prototype was proposed. Characterization of nanoparticles was made by dynamic light scattering (DLS), X-ray diffraction (XRD) and magnetic measurements. Mechanical, thermal and radiopacity properties were evaluated for composites formulation. In vitro, radiopaque experiments showed that BM-2 composite had the best performance. In vivo experiments showed that, after five months, the marker clip prototype maintained its shape, visibility and contrast properties. In consequence, a novel formulation of composite (PLA-PCL/metallic nanoparticles) is suitable for further studies as an alternative material for marker clips for breast cancer lesions.

5.
Mater Sci Eng C Mater Biol Appl ; 57: 49-57, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26354239

RESUMEN

Several types of dyes or fluorophores are used for the detection of interactions between drug carriers and cells, within biomedicine field. However, many of them have a certain level of toxicity and instability affecting their biological properties. Different studies have demonstrated that nanoparticles (NPs) have interesting properties that could be used to stabilize diverse biomolecules, including dyes. Here, we report the synthesis of a novel nanosystem by the functionalization of silica NPs using biocompounds extracted from Mexican tree "Palo azul" (Eysenhardtia polystachya) and APTES as a coupling agent. Particle size, electrical properties, and morphology of the novel nanosystem were analyzed. The extracted biocompounds presented fluorescence which prevails over time, even after nanosystem formation and apparent cellular internalization. These were detected using MCF-7 cells visualized by confocal laser-scanning microscopy (CLSM), finding that the nanosystem was able to internalize into cells and act as a fluorescent biomarker. By this method, our novel nanosystem opens the possibilities to obtain sensitive data in a noninvasive manner for biological applications, such as early-stage cancer diagnosis, drug delivery, and pathogen detection.


Asunto(s)
Neoplasias de la Mama/patología , Fabaceae/química , Colorantes Fluorescentes/química , Microscopía Fluorescente/métodos , Nanopartículas/química , Dióxido de Silicio/química , Medios de Contraste , Cristalización/métodos , Colorantes Fluorescentes/aislamiento & purificación , Humanos , Células MCF-7 , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación
6.
J Vasc Res ; 47(1): 45-53, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19672107

RESUMEN

Angiogenesis is essential for the growth and maturation of the ovarian follicle and its transition into the corpus luteum. In addition to the main proangiogenic factors, vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), follicular fluid (FF) contains the hormone prolactin (PRL), which is known to promote angiogenesis in vivo. Here, we show that FF from large follicles, which contains twice the PRL level of FF from small follicles, stimulates endothelial cell proliferation to a greater extent than the latter, and that immunoneutralization of PRL prevents FF from stimulating endothelial cell proliferation. Notably, the FF increases the expression of the short and long PRL receptor isoforms in endothelial cells, and a purified PRL standard stimulates endothelial cell proliferation but only after the cells have been pretreated with FF. However, purified PRL activates the JAK2/STAT3 pathway in endothelial cells in the absence of pretreatment with FF. In summary, PRL present in the FF stimulates the proliferation of endothelial cells. This effect likely involves the upregulation of the short and long PRL receptor isoforms and is independent of PRL-induced JAK2/STAT3 signaling.


Asunto(s)
Proliferación Celular , Células Endoteliales/metabolismo , Líquido Folicular/metabolismo , Neovascularización Fisiológica , Prolactina/metabolismo , Animales , Bovinos , Células Cultivadas , Femenino , Janus Quinasa 2/metabolismo , Fosforilación , Isoformas de Proteínas , Receptores de Prolactina/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Factores de Tiempo
7.
Endocrinology ; 150(12): 5446-54, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19819948

RESUMEN

Vasoinhibins are a family of N-terminal prolactin (PRL) fragments that inhibit blood vessel growth, dilation, permeability, and survival. The aspartyl endoprotease cathepsin D is active at acidic pH and can cleave rat PRL to generate vasoinhibins. We investigated whether and where vasoinhibins could be generated by cathepsin D in the adenohypophysis of rats and mice and whether their production could be gender dependent. Vasoinhibins were detected in primary cultures of rat adenohypophyseal cells by Western blot with antibodies directed against the N terminus of PRL but not the C terminus. Ovariectomized, estrogen-treated females show greater levels of adenohypophyseal vasoinhibins than males. Peptide sequencing analysis revealed that the cleaved form of PRL in rat adenohypophyseal extracts contains the PRL N terminus and a second N terminus starting at Ser(149), the reported cleavage site of cathepsin D in rat PRL. In addition, cathepsin D inhibition by pepstatin A reduced vasoinhibin levels in rat adenohypophyseal cell cultures. Confocal and electron microscopy showed the colocalization of cathepsin D and PRL within rat adenohypophyseal cells and secretory granules, and a subcellular fraction of rat adenohypophysis enriched in secretory granules contained cathepsin D activity able to generate vasoinhibins from PRL. Of note, vasoinhibins were absent in the adenohypophysis of mice lacking the cathepsin D gene but not in wild-type mice. These findings show that cathepsin D is the main protease responsible for the generation of adenohypophyseal vasoinhibins and that its action can take place within the secretory granules of lactotrophs.


Asunto(s)
Catepsina D/metabolismo , Adenohipófisis/metabolismo , Prolactina/metabolismo , Vesículas Secretoras/metabolismo , Animales , Western Blotting , Catepsina D/genética , Células Cultivadas , Femenino , Técnica del Anticuerpo Fluorescente , Masculino , Ratones , Ratones Noqueados , Microscopía Electrónica , Fragmentos de Péptidos/metabolismo , Adenohipófisis/citología , Adenohipófisis/ultraestructura , Prolactina/química , Ratas , Ratas Wistar , Vesículas Secretoras/ultraestructura
8.
J Endocrinol ; 191(1): 45-53, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17065388

RESUMEN

Human pituitary tumor-transforming gene 1 (PTTG1) encodes a securin protein critically important in regulating chromosome separation. Murine PTTG (mPTTG) is 66% homologous to human PTTG1 and PTTG-null (PTTG-/-) mice exhibit pancreatic beta-cell hypoplasia and abnormal nuclear morphology with resultant diabetes. As we show that ductal beta-cell neogenesis is intact in PTTG-/- mice, we explored mechanism for defective beta-cell replication. We tested whether mPTTG exhibits securin properties in mouse insulin-secreting insulinoma MIN6 cells, using a live-cell system to monitor mitosis in cells transfected with an enhanced green fluorescent protein (EGFP)-tagged mPTTG conjugate (mPTTG-EGFP). To fulfill the criteria for securin properties, the protein should undergo degradation immediately before the metaphase-to-anaphase transition when expression levels are low, and should inhibit metaphase-to-anaphase transition when expression levels are high. EGFP itself did not undergo degradation throughout mitosis and high levels of EGFP per se did not affect normal mitosis progression (n=25). However, mPTTG-EGFP was degraded 2 min before the metaphase-to-anaphase transition when expression levels were low (n=19), and high mPTTG-EGFP levels blocked metaphase-to-anaphase transition in 13 cells. mPTTG-EGFP inhibited MIN6 cell proliferation and caused apoptosis. Immunocoprecipitation demonstrated binding of mPTTG-EGFP and separase. These results show that mPTTG exhibits properties consistent with a murine securin in insulin-secreting mouse cells and mPTTG overexpression inhibits cell proliferation, suggesting that defective beta-cell proliferation observed in PTTG-/- mice is likely due to abnormal cell-cycle progression.


Asunto(s)
Células Secretoras de Insulina/metabolismo , Proteínas de Neoplasias/genética , Anafase , Animales , Apoptosis , Western Blotting/métodos , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Endopeptidasas/metabolismo , Técnica del Anticuerpo Fluorescente , Expresión Génica , Proteínas Fluorescentes Verdes/genética , Humanos , Inmunoprecipitación , Células Secretoras de Insulina/citología , Insulinoma , Metafase , Ratones , Ratones Noqueados , Proteínas de Neoplasias/metabolismo , Securina , Separasa , Transfección/métodos
10.
Endocrinology ; 143(11): 4429-36, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12399440

RESUMEN

Targeted disruption [knockout (KO)] of the mouse prolactin (PRL) gene created an animal model of primary isolated PRL deficiency in which there is no detectable PRL bioactivity. Pituitary glands of young adult female PRLKO mice were hyperplastic, and many cells had expanded cytoplasms with granular accumulations of an N-terminal peptide encoded by the disrupted PRL gene (KO/10 peptide). Confocal imaging showed that the pituitaries in PRL(+/+) and PRL(+/-) females contained dense accumulations of apparently Golgi-associated immunoreactive PRL. PRLKO female mice (15-18 months old) developed hyperemic pituitary adenomas. The pituitary tumors in PRLKO mice synthesized the KO/10 peptide, which implies that the tumors arise from the lactotroph lineage. Anchorage-independent growth was observed among pituitary cells from PRLKO mice, aged 8 months or older, but not in cells from 3-month-old PRLKO mice. GH cells appeared to be normal in PRLKO pituitaries, but were displaced by the hyperplastic and hypertrophic growth of KO/10-positive cells. Bromocriptine suppressed mean pituitary weight in 8-month-old PRLKO mice compared with vehicle-treated PRLKO animals (20 +/- 0.01 and 60 +/- 10 mg; P < 0.01). We infer that pituitary lactotrophs of PRLKO mice suffer from a dual pathology that includes hypertrophy resulting from endoplasmic reticulum expansion and hyperplasia, with adenomatous transformation, in part as a consequence of disrupted dopaminergic feedback regulation.


Asunto(s)
Adenoma/genética , Neoplasias Hipofisarias/genética , Prolactina/deficiencia , Prolactina/genética , Adenoma/tratamiento farmacológico , Adenoma/patología , Animales , Bromocriptina/uso terapéutico , Dopamina/fisiología , Retículo Endoplásmico/patología , Estrógenos/sangre , Retroalimentación , Femenino , Técnica del Anticuerpo Fluorescente , Hormona del Crecimiento/análisis , Hiperplasia , Inmunohistoquímica , Ratones , Ratones Noqueados , Microscopía Confocal , Hipófisis/química , Hipófisis/patología , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/patología , Prolactina/análisis
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