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1.
Int J Mol Sci ; 20(15)2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31387202

RESUMEN

Rett syndrome (RTT) is a rare, X-linked neurodevelopmental disorder typically affecting females, resulting in a range of symptoms including autistic features, intellectual impairment, motor deterioration, and autonomic abnormalities. RTT is primarily caused by the genetic mutation of the Mecp2 gene. Initially considered a neuronal disease, recent research shows that glial dysfunction contributes to the RTT disease phenotype. In the following manuscript, we review the evidence regarding glial dysfunction and its effects on disease etiology.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Proteína 2 de Unión a Metil-CpG/deficiencia , Neuroglía/metabolismo , Síndrome de Rett/genética , Síndrome de Rett/metabolismo , Animales , Astrocitos/metabolismo , Metabolismo Energético , Estudios de Asociación Genética/métodos , Humanos , Oligodendroglía/metabolismo , Fenotipo , Síndrome de Rett/diagnóstico
2.
Behav Pharmacol ; 27(2-3 Spec Issue): 182-4, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26176409

RESUMEN

Early life stress interacts with adult stress to differentially modulate neural systems and vulnerability to various psychiatric illnesses. However, the effects of early life stress and adult stress on addictive behaviors have not been sufficiently investigated. We examined the effects of early life stress in the form of prolonged maternal separation, followed in early adulthood by either 10 days of chronic variable stress or no stress, on methamphetamine self-administration, extinction, and cue-induced reinstatement. We observed that chronic variable stress in adulthood reduced methamphetamine self-administration in rats with a history of early life stress. These findings add to an emerging body of literature suggesting interactions between early life and early adulthood stressors on adult behavioral phenotypes.


Asunto(s)
Estimulantes del Sistema Nervioso Central/administración & dosificación , Metanfetamina/administración & dosificación , Estrés Psicológico/tratamiento farmacológico , Animales , Animales Recién Nacidos , Condicionamiento Operante/efectos de los fármacos , Señales (Psicología) , Modelos Animales de Enfermedad , Extinción Psicológica/efectos de los fármacos , Femenino , Masculino , Privación Materna , Embarazo , Ratas , Ratas Long-Evans , Refuerzo en Psicología , Autoadministración , Factores de Tiempo
3.
Invest Clin ; 57(3): 259-66, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29938478

RESUMEN

The aim of this study was to examine the lip projection of brachycephalic, dolichocephalic and mesocephalic Mexican patients and to analyze the relationship between dental protrusion and the lip position, to identify if a labial soft tissue projection exists and to determine what features predominated in this study. A total of 120 lateral radiographs of the skull were randomly selected from patients aged 16-25 years. The linear and angular data were measured, the values of the upper and lower lip projection relative to Ricketts E-line, Steiner S-line and Arnett TV-line were collected. The angles to be analyzed were the nasolabial, mandibular plane and interincisal, and the mentolabial groove depth. The statistical significance was determined by the Student t-test. A significant difference between mesocephalic and brachycephalic patients was observed measuring the angle between the Frankfurt plane and the mandibular plane (P<0.001). Between dolichocephalic and mesocephalic individuals significant differences were observed in the lower lip to E-line (P<0.031), lower lip to S-line (P<0.010), the interincisal angle (P<0.032) and the mandibular´s plane (P<0.001). A statistical significant difference was shown between brachycephalic and dolichocephalic individuals: lower lip to E-line (P<0.001), upper lip to S-line (P<0.037), lower lip to S-line (P<0.001), interincisal angle (P<0.034) and the angle between the mandibular´s plane (P<0.001). Lip soft tissue projection will depend on the population studied; we found some significant differences when compared with the cephalometric norms.


Asunto(s)
Craneosinostosis/complicaciones , Labio/anomalías , Adolescente , Adulto , Cefalometría , Humanos , Adulto Joven
4.
Invest Clin ; 57(4): 321-9, 2016 Dec.
Artículo en Español | MEDLINE | ID: mdl-29938980

RESUMEN

The antimicrobial efficacy of the silver nanoparticles (NPsAg), incorporated into the adhesive (primer) placed in the enamel adjacent to fixed orthodontic appliances (brackets), was evaluated. An experimental study was performed on 40 premolars in vitro, which were divided into two groups with brackets, one cemented with conventional primer and another added with NPsAg, placed in culture media previously inoculated with Streptococcus mutans, and sampled for culturing and counting colony forming units (UFC) on days 1, 15 and 30. A decrease in the presence of Streptococcus mutans in the samples after 15 days with nanoparticle aggregation was observed, and a reduction in the effect of said nanoparticles after 30 days. This reduction of the nanoparticles effects can be due to the absence of mechanical cleaning, which favored the bacterial aggregation on the biofilm, affecting its antimicrobial effect. This suggest the need for realizing studies in "vivo" which will allow the observation of the behavior of the biometals on the buccal medium. The NPsAg added to the primer are an effective tool to prevent the demineralization of the enamel around the fixed orthodontic appliances.


Asunto(s)
Antibacterianos/farmacología , Cementos Dentales , Nanopartículas del Metal , Aparatos Ortodóncicos/microbiología , Plata , Estudios Transversales , Técnicas In Vitro
5.
Int J Neuropsychopharmacol ; 18(1)2014 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-25522379

RESUMEN

BACKGROUND: Use of synthetic cathinones, which are designer stimulants found in "bath salts," has increased dramatically in recent years. Following governmental bans of methylenedioxypyrovalerone, mephedrone, and methylone, a second generation of synthetic cathinones with unknown abuse liability has emerged as replacements. METHODS: Using a discrete trials current intensity threshold intracranial self-stimulation procedure, the present study assessed the effects of 2 common second-generation synthetic cathinones, α-pyrrolidinopentiophenone (0.1-5 mg/kg) and 4-methyl-N-ethcathinone (1-100 mg/kg) on brain reward function. Methamphetamine (0.1-3 mg/kg) was also tested for comparison purposes. RESULTS: Results revealed both α-pyrrolidinopentiophenone and 4-methyl-N-ethcathinone produced significant intracranial self-stimulation threshold reductions similar to that of methamphetamine. α-Pyrrolidinopentiophenone (1 mg/kg) produced a significant maximal reduction in intracranial self-stimulation thresholds (~19%) most similar to maximal reductions produced by methamphetamine (1 mg/kg, ~20%). Maximal reductions in intracranial self-stimulation thresholds produced by 4-methyl-N-ethcathinone were observed at 30 mg/kg (~15%) and were comparable with those observed with methamphetamine and α-pyrrolidinopentiophenone tested at the 0.3-mg/kg dose (~14%). Additional analysis of the ED50 values from log-transformed data revealed the rank order potency of these drugs as methamphetamine ≈ α-pyrrolidinopentiophenone>4-methyl-N-ethcathinone. CONCLUSIONS: These data suggest that the newer second-generation synthetic cathinones activate the brain reward circuitry and thus may possess a similar degree of abuse potential as prototypical illicit psychostimulants such as methamphetamine as well as the first generation synthetic cathinone methylenedioxypyrovalerone, as previously reported.


Asunto(s)
Estimulantes del Sistema Nervioso Central/farmacología , Pentanonas/farmacología , Pirrolidinas/farmacología , Autoestimulación/efectos de los fármacos , Animales , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Estimulantes del Sistema Nervioso Central/química , Relación Dosis-Respuesta a Droga , Drogas Ilícitas , Modelos Lineales , Masculino , Metanfetamina/química , Metanfetamina/farmacología , Estructura Molecular , Pentanonas/química , Pirrolidinas/química , Ratas Sprague-Dawley
6.
Toxicon ; 244: 107753, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38740098

RESUMEN

This review analyzes the current progress in loaded nanoparticles (NPs) of plant extracts or isolated antineoplastic compounds used in breast and cervical cancer treatments. Also, it provides a comprehensive overview of the contributions made by traditional medicine and nanomedicine to the research of two of the most prevalent types of cancer in women worldwide: breast and cervical cancer. Searches were conducted in electronic databases to gather relevant information related to the biological activity of the NPs, which were meticulously reviewed. Nanomedicine has advanced to incorporate plant compounds including their crude extracts, in the preparation of NPs. The most used method is green synthesis, whose most outstanding advantages, is the reduced preparation time, and the variety of results that can be obtained depending on the reaction times, pH, temperature, and concentration of both the bio-reducing agent and the compound or plant extract. Most of the studies focus on evaluating crude extracts with high polarity, such as aqueous, alcoholic, and hydroalcoholic extracts. In conclusion, exploring the use of organic compounds is considered an area of opportunity for further research and future perspectives. Most of the analyzed studies were conducted using in vitro assays, highlighting the relatively recent nature of this field. It is expected that future research will involve more in vivo assays, particularly focusing on isolated cell lines representing the most difficult-to-treat types of cancer, such as triple-negative breast cancer like MDA-MB-231. Notably the MCF-7 cell line is one of the most used, while limited studies were found concerning cervical cancer.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Extractos Vegetales , Neoplasias del Cuello Uterino , Humanos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Antineoplásicos Fitogénicos/farmacología , Nanomedicina
7.
Biomed Res Int ; 2023: 5584412, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37700878

RESUMEN

Background: The resistance to antibiotics shown by some dermatological pathogenic microorganisms has increased the interest of pharmaceutical and cosmetic industries in developing natural products that possess different biological activities, including antimicrobial effects. Methods: In the present investigation, the antibacterial activity of ethanolic extracts of Dodonaea viscosa aerial part and Mammea americana leaves and seed was evaluated against resistant strains of Staphylococcus isolated from skin lesions and against S. aureus ATCC 25923 (reference strain). Column chromatography (CC) and preparative thin-layer chromatography (PTLC) were used to obtain separate fractions of the seed extract of M. americana. We also determined the antimicrobial resistance of the strains against antibiotics using the agar disc diffusion assay. In addition, phytochemical screening was performed by colorimetric standard techniques. Results: M. americana seed extract showed the highest antibacterial activity with MBC from 2.3 µg/mL to 19.5 µg/mL without differences with gentamicin (p = 0.998). The isolated strain S. epidermidis I showed the highest antimicrobial resistance against the tested antibiotics. PTLC-fractions of M. americana seed extract showed MBC from 3.2 µg/mL to 40.7 µg/mL against S. epidermidis I and S. aureus 25923 (reference), respectively, which suggests a synergistic effect of the secondary metabolites present in the crude ethanolic extract compared to its active PTLC-fractions, where only coumarins and compounds with lactone groups were detected in the phytochemical screening. Conclusion: M. americana seed extract has promising effects that should be considered in further studies as an alternative or adjuvant in treating skin infections caused by staphylococci.


Asunto(s)
Mammea , Enfermedades de la Piel , Staphylococcus , Staphylococcus aureus , Antibacterianos/farmacología , Staphylococcus epidermidis , Etanol , Extractos Vegetales/farmacología
8.
Nanoscale ; 15(14): 6793-6801, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36946985

RESUMEN

The introduction of oligoether side chains onto a polymer backbone can help to stabilise polymeric dispersions in water without the necessity of surfactants or additives when conjugated polymer nanoparticles are prepared. A series of poly(3-hexylthiophene) (P3HT) derivatives with different content of a polar thiophene derivative 3-((2-methoxyethoxy)methyl)thiophene was interrogated to find the effect of the polar chains on the stability of the formed nanoparticles, as well as their structural, optical, electrochemical, and electrical properties. Findings indicated that incorporation of 10-20 percent of the polar side chain led to particles that are stable over a period of 42 days, with constant particle size and polydispersity, however the particles from the polymer with 30 percent polar side chain showed aggregation effects. The polymer dispersions showed a stronger solid-like behaviour in water with decreasing polar side chain content, while thin film deposition from water was found to afford globular morphologies and crystallites with more isotropic orientation compared to conventional solution-processed films. As a proof-of-principle, field-effect transistors were fabricated directly from the aqueous dispersions demonstrating that polymers with hydrophilic moieties can be processed in water without the requirement of surfactants.

9.
Artículo en Inglés | MEDLINE | ID: mdl-35805583

RESUMEN

The usefulness of traditional plants in Mexico to treat human ailments has been known since ancient times. This work evaluated the antimicrobial, anticoagulant, antioxidant, cytotoxic, and anti-inflammatory potential of ethanolic extracts of Aloe vera, Equisetum arvense, Mimosa tenuiflora, Lippia graveolens, and Syzygium aromaticum. The antimicrobial activity of the extracts was evaluated against Streptococcus mutans and Streptococcus sorbinus; a significant inhibitory effect of the L. graveolens extract on both bacteria was observed at concentration levels of 250 µg/mL and greater. The anticoagulant activity was evaluated in terms of prothrombin time (PT) and activated partial thromboplastin time (APTT), A. vera and M. tenuiflora extracts showed no significant difference (p ˂ 0.05) in PT compared with the control, and for APTT the extracts of A. vera, L. graveolens, and S. aromaticum decreased the APTT significantly (p ˂ 0.05) compared with the control. The antioxidant potential by DPPH assay indicated that the E. arvense extract behaved statistically the same as the control. The cytotoxic activity was evaluated in HGF-1 cells using the fluorometric microculture cytotoxicity assay technique, and none of the extracts was toxic at 125 and 250 µg/mL concentrations. Finally, the anti-inflammatory activity was evaluated using ELISA, where the A. vera extract showed the best anti-inflammatory capacity. Further research on the search for bioactive metabolites and elucidation of action mechanisms of the most promising extracts will be carried out.


Asunto(s)
Antiinfecciosos , Plantas Medicinales , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Antiinflamatorios/farmacología , Anticoagulantes/farmacología , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Odontología , Humanos , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico
10.
JCI Insight ; 7(15)2022 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-35737458

RESUMEN

Circulating monocytes have emerged as key regulators of the neuroinflammatory milieu in a number of neuropathological disorders. Ephrin type A receptor 4 (Epha4) receptor tyrosine kinase, a prominent axon guidance molecule, has recently been implicated in the regulation of neuroinflammation. Using a mouse model of brain injury and a GFP BM chimeric approach, we found neuroprotection and a lack of significant motor deficits marked by reduced monocyte/macrophage cortical infiltration and an increased number of arginase-1+ cells in the absence of BM-derived Epha4. This was accompanied by a shift in monocyte gene profile from pro- to antiinflammatory that included increased Tek (Tie2 receptor) expression. Inhibition of Tie2 attenuated enhanced expression of M2-like genes in cultured Epha4-null monocytes/macrophages. In Epha4-BM-deficient mice, cortical-isolated GFP+ monocytes/macrophages displayed a phenotypic shift from a classical to an intermediate subtype, which displayed reduced Ly6chi concomitant with increased Ly6clo- and Tie2-expressing populations. Furthermore, clodronate liposome-mediated monocyte depletion mimicked these effects in WT mice but resulted in attenuation of phenotype in Epha4-BM-deficient mice. This demonstrates that monocyte polarization not overall recruitment dictates neural tissue damage. Thus, coordination of monocyte proinflammatory phenotypic state by Epha4 is a key regulatory step mediating brain injury.


Asunto(s)
Lesiones Encefálicas , Monocitos , Humanos , Lesiones Encefálicas/metabolismo , Efrinas/metabolismo , Monocitos/metabolismo , Fenotipo , Receptor EphB2/metabolismo , Animales , Ratones
11.
Chem Sci ; 13(2): 421-429, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-35126974

RESUMEN

A modular approach to underexplored, unsymmetrical [1]benzothieno[3,2-b][1]benzothiophene (BTBT) scaffolds delivers a library of BTBT materials from readily available coupling partners by combining a transition-metal free Pummerer CH-CH-type cross-coupling and a Newman-Kwart reaction. This effective approach to unsymmetrical BTBT materials has allowed their properties to be studied. In particular, tuning the functional groups on the BTBT scaffold allows the solid-state assembly and molecular orbital energy levels to be modulated. Investigation of the charge transport properties of BTBT-containing small-molecule:polymer blends revealed the importance of molecular ordering during phase segregation and matching the highest occupied molecular orbital energy level with that of the semiconducting polymer binder, polyindacenodithiophene-benzothiadiazole (PIDTBT). The hole mobilities extracted from transistors fabricated using blends of PIDTBT with phenyl or methoxy functionalized unsymmetrical BTBTs were double those measured for devices fabricated using pristine PIDTBT. This study underscores the value of the synthetic methodology in providing a platform from which to study structure-property relationships in an underrepresented family of unsymmetrical BTBT molecular semiconductors.

12.
J Ethnopharmacol ; 297: 115552, 2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-35863615

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Urolithiasis is the presence of stones in the kidney, ureters, bladder and/or urethra; it is the third most frequent disease of the urinary tract. Mimosa malacophylla A. Gray, is a species distributed in northern Mexico, where people traditionally use it for its diuretic effect, and to treat kidney diseases; however, no scientific reports have been found in relation to its antiurolithic properties. AIM OF THE STUDY: This study aimed to obtain a qualitative phytochemical profile of the methanolic extract (ME) of M. malacophylla, and to evaluate its potential cytotoxic effect in vitro and its antiurolithic activity in vivo. MATERIAL AND METHODS: Phytochemical screening was performed to demonstrate the presence of secondary metabolite groups in the methanolic extract of M. malacophylla. In vitro cytotoxicity assays (MTT and nucleotide labeling with DAPI) were performed to evaluate the effect of the extract on kidney cell lines. Urolithiasis was induced in the bladder of Wistar rats introducing zinc disks for the calculus formation and exposed to three concentrations of ME. RESULTS: Phytochemical screening showed phenols, steroids, terpenoids and carbohydrates. In vitro analysis demonstrated that concentrations below 300 µg/mL of ME did not produce a cytotoxic effect on renal Vero and HEK-293 cells. In vivo analysis of 15 days of exposition, revealed that the extract at concentrations of 50 mg/kg to 150 mg/kg were effective as an antiurolithic treatment, and did not produce morphological alterations in kidney or bladder in murine model of induced urolithiasis. CONCLUSIONS: The antiurolithic activity may be attributed to the presence of flavonoids, steroids and terpenes detected in the phytochemical screening which have been reported to possess this activity. These results could be useful to evaluate new alternatives and their potential therapeutic effect to treat renal or urinary affections.


Asunto(s)
Mimosa , Urolitiasis , Animales , Células HEK293 , Humanos , Riñón , Metanol/farmacología , Ratones , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar , Vejiga Urinaria , Urolitiasis/inducido químicamente
13.
Plants (Basel) ; 10(9)2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34579443

RESUMEN

The genus Zingiberaceae has been widely used for phytotherapeutic purposes in traditional medicine throughout the world for its anti-inflammatory activity. Experimental studies have established that inflammation caused by chronic infections represents a risk factor for different forms of cancer. The objective of this study was focused on determining the anti-inflammatory capacity and cytotoxic activity of aqueous extracts of Elettaria cardamomum (cardamom) and Curcuma Longa (turmeric). The extracts were obtained by maceration and, through GC-MS/MS, a total of 11 different chemical components were determined in the aqueous extract of cardamom and 7 in the extract of turmeric. The main compounds found in cardamom and turmeric were α-terpinyl acetate (54.46%) and ß-turmerone (33.45%), respectively. RT-qPCR results showed significantly lower gene expression levels of innate inflammatory cytokines (IL-6 and TNF-α) compared to the control (LPS). Also, it was observed that the extracts do not possess cytotoxic activity against different cell lines, where E. cardamomum showed EC50 (µg/mL) of 473.84 (HeLa cells), 237.36 (J774A.1 cells), 257.51 (Vero E6 cells), and 431.16 (Balb/C peritoneal cells) and C. longa showed EC50 (µg/mL) of 351.17 (HeLa cells), 430.96 (J774A.1 cells), 396.24 (Vero E6 cells), and 362.86 (Balb/C peritoneal cells). The results of this research suggest that natural extracts of E. cardamomum and C. longa possess anti-inflammatory effects and no cytotoxic activity against HeLa, J774A.1, Vero E6, and Balb/C peritoneal cell lines. Finally, it was observed that the extracts also decreased nitric oxide (NO) production in peritoneal macrophages.

14.
Plants (Basel) ; 10(11)2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34834687

RESUMEN

Acalypha monostachya (A. monostachya) is a plant that is used in traditional medicine as a cancer treatment; however, its effect has not been validated. In this study, the potential cytotoxic effects and morphological changes of A. monostachya were evaluated in human tumor cell lines. The aqueous (AE), methanolic (ME), and hexane (HE) extracts were obtained, and flavonoid-type phenolic compounds were detected, which indicates an antineoplastic effect. We observed a time-dependent and concentration-selective toxicity in human tumor cells. Additionally, the ME and HE showed the greatest cytotoxic effect at minimum concentrations compared to the AE, which showed this effect at the highest concentrations. All extracts induced significant morphological changes in tumor cells. The HeLa (cervix carcinoma) cells were more sensitive compared to the MDA-MB-231 (triple-negative breast cancer) cells. In conclusion, we demonstrated a cytotoxic in vitro effect of A. monostachya extracts in tumoral human cell lines. These results show the potential antineoplastic effects of A. monostachya in vitro. Hereafter, our lab team will continue working to usefully isolate and obtain the specific compounds of A. monostachya extracts with cytotoxic effects on tumor cells to find more alternatives for cancer treatment.

15.
Adv Biosyst ; 4(1): e1900225, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-32293127

RESUMEN

Here, a 3D printed multiplexed competitive migration assay is reported for characterizing a chemotactic response in the presence of multiple spatially distributed chemoattractants. The utility of the assay is demonstrated by examining the chemotactic response of human glioblastoma cells to spatially opposing chemotactic gradients of epidermal growth factor (EGF) and bradykinin (BK). Competitive migration assays involving spatially opposing gradients of EGF and BK that are optimized in the absence of the second chemoattractant show that 46% more glioblastoma cells migrate toward EGF sources. The migration velocities of human glioblastoma cells toward EGF and BK sources are reduced by 7.6 ± 2.2% and 11.6 ± 6.3% relative to those found in the absence of the spatially opposing chemoattractant. This work provides new insight to the chemotactic response associated with glioblastoma-vasculature interactions and a versatile, user-friendly platform for characterizing the chemotactic response of cells in the presence of multiple spatially distributed chemoattractants.


Asunto(s)
Ensayos de Migración Celular , Factores Quimiotácticos/farmacología , Quimiotaxis/efectos de los fármacos , Impresión Tridimensional , Bradiquinina/farmacología , Línea Celular Tumoral , Ensayos de Migración Celular/instrumentación , Ensayos de Migración Celular/métodos , Factor de Crecimiento Epidérmico/farmacología , Diseño de Equipo , Glioblastoma , Humanos , Técnicas Analíticas Microfluídicas/instrumentación
16.
Adv Sci (Weinh) ; 7(21): 2002010, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33173736

RESUMEN

Organic semiconductors (OSCs) promise to deliver next-generation electronic and energy devices that are flexible, scalable and printable. Unfortunately, realizing this opportunity is hampered by increasing concerns about the use of volatile organic compounds (VOCs), particularly toxic halogenated solvents that are detrimental to the environment and human health. Here, a cradle-to-grave process is reported to achieve high performance p- and n-type OSC devices based on indacenodithiophene and diketopyrrolopyrrole semiconducting polymers that utilizes aqueous-processes, fewer steps, lower reaction temperatures, a significant reduction in VOCs (>99%) and avoids all halogenated solvents. The process involves an aqueous mini-emulsion polymerization that generates a surfactant-stabilized aqueous dispersion of OSC nanoparticles at sufficient concentration to permit direct aqueous processing into thin films for use in organic field-effect transistors. Promisingly, the performance of these devices is comparable to those prepared using conventional synthesis and processing procedures optimized for large amounts of VOCs and halogenated solvents. Ultimately, the holistic approach reported addresses the environmental issues and enables a viable guideline for the delivery of future OSC devices using only aqueous media for synthesis, purification and thin-film processing.

17.
Elife ; 82019 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-31433295

RESUMEN

Brain-derived neurotrophic factor (BDNF) is a critical growth factor involved in the maturation of the CNS, including neuronal morphology and synapse refinement. Herein, we demonstrate astrocytes express high levels of BDNF's receptor, TrkB (in the top 20 of protein-coding transcripts), with nearly exclusive expression of the truncated isoform, TrkB.T1, which peaks in expression during astrocyte morphological maturation. Using a novel culture paradigm, we show that astrocyte morphological complexity is increased in the presence of BDNF and is dependent upon BDNF/TrkB.T1 signaling. Deletion of TrkB.T1, globally and astrocyte-specifically, in mice revealed morphologically immature astrocytes with significantly reduced volume, as well as dysregulated expression of perisynaptic genes associated with mature astrocyte function. Indicating a role for functional astrocyte maturation via BDNF/TrkB.T1 signaling, TrkB.T1 KO astrocytes do not support normal excitatory synaptogenesis or function. These data suggest a significant role for BDNF/TrkB.T1 signaling in astrocyte morphological maturation, a critical process for CNS development.


Asunto(s)
Astrocitos/citología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Diferenciación Celular , Glicoproteínas de Membrana/metabolismo , Morfogénesis , Proteínas Tirosina Quinasas/metabolismo , Transducción de Señal , Animales , Células Cultivadas , Glicoproteínas de Membrana/deficiencia , Ratones , Ratones Noqueados , Isoformas de Proteínas/metabolismo , Proteínas Tirosina Quinasas/deficiencia
18.
Horiz. sanitario (en linea) ; 21(3): 397-402, Sep.-Dec. 2022. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1506350

RESUMEN

Resumen Objetivo: Evaluar la actividad antibacteriana de los extractos de Mimosa tenuiflora, Equisetum arvense, Syzygium aromaticum, Lippia graveolens y Aloe vera contra cepas bacterianas de S. mutans (ATCC700611) y S. sobrinus (ATCC33478) comparado con clorhexidina a 1200 µg/mL (0.12%) y la actividad coagulante en sangre humana. Materiales y métodos: Estudio comparativo, abierto, experimental, prospectivo y transversal in vitro. Se realizaron diluciones a 500 y 1000 µg/mL de cinco extractos y se probaron por triplicado contra microorganismos orales por medio de técnica de pozo en agar y en la evaluación de la actividad coagulante se probaron los cinco extractos por triplicado en sangre humana evaluando TP (tiempo de protrombina) y TTPa (tiempo de tromboplastina parcial activado) mediante coagulómetro. Resultados: El extracto de Lippia graveolens a 500 y 1000 µg/mL mostró un promedio de halos de inhibición sobre S. mutans de 26mm con respecto a clorhexidina a 1200 µg/mL que mostró un promedio de 15mm. Contra cepas de S. sobrinus mostraron un promedio de 19mm a 500 µg/mL y 23mm a 1000 µg/mL con respecto a 15mm de clorhexidina. El valor de TP (tiempo de protrombina) de la muestra de sangre fue 12.27 segundos, al aplicarle E. arvense y S. aromaticum ambos a 1000 µg/mL presentaron tiempos de 13.37 segundos. En cuanto al tiempo de tromboplastina parcial activada (TTPa) el valor de la muestra sin extracto fue 32.63 segundos, al aplicar M. tenuiflora a 500 µg/mL se aumentó el tiempo a 39.17 segundos. Conclusiones: Se concluye que Lippia graveolens tiene mejor efecto antibacteriano contra micrrorganismos orales y M. tenuiflora fue el extracto que aumentó por más tiempo el valor de TTPa.


Abstract Objective: To evaluate the antimicrobial and coagulating activity from five vegetables of ethnobotanical interest extracts (Mimosa tenuiflora, Equisetum arvense, Syzygium aromaticum, Lippia graveolens and Aloe vera). Materials and methods: It was a Comparative, open, experimental, prospective and cross-sectional study through antimicrobial evaluation of the five extracts against bacterial strains of S. mutans (ATCC700611) and S. sobrinus (ATCC33478) by means of agar well technique and an evaluation of coagulating activity by measuring TP (prothrombin time) and APTT (activated partial thromboplastin time) using a coagulometer and comparing the results with those of a healthy patient. Results: It was found that the antimicrobial activity of the extracts on S. mutans at 500 and 1000ppm is statistically significant in the extracts of E. arvense and L. graveolens (p= 0.0057) and (p= 0.0000) respectively and on strains of S. sobrinus from the extracts of A. vera (p= 0.0011) and L. graveolens (p= 0.0089) in both concentrations, which show an antimicrobial effect superior to chlorhexidine. The PT patient's (prothrombin time) value was 12.27 seconds, no statistical difference was observed with a value of (p<0.05), however, E. arvense and S. aromaticum, both at 1000ppm, presented times of 13.37 seconds and at the activated partial thromboplastin time (PTPA) the value of the patient was 32.63 seconds, highlighting M. tenuiflora at 500 ppm, which presented times of 39.17 seconds. Conclusions: The extracts described above contain chemical compounds that are valuable alternatives against microorganisms and oral treatments, and it is also very important that research suggests materials and medications that are effective in the treatment of patients and that do not represent a health risk.

19.
Invest. clín ; 57(3): 259-266, Sept. 2016. ilus, graf
Artículo en Inglés | LILACS | ID: biblio-841116

RESUMEN

The aim of this study was to examine the lip projection of brachycephalic, dolichocephalic and mesocephalic Mexican patients and to analyze the relationship between dental protrusion and the lip position, to identify if a labial soft tissue projection exists and to determine what features predominated in this study. A total of 120 lateral radiographs of the skull were randomly selected from patients aged 16-25 years. The linear and angular data were measured, the values of the upper and lower lip projection relative to Ricketts E-line, Steiner S-line and Arnett TV-line were collected. The angles to be analyzed were the nasola bial, mandibular plane and interincisal, and the mentolabial groove depth. The statistical sig nificance was determined by the Student t-test. A significant difference between mesocephalic and brachycephalic patients was observed measuring the angle between the Frankfurt plane and the mandibular plane (P<0.001). Between dolichocephalic and mesocephalic individuals significant differences were observed in the lower lip to E-line (P<0.031), lower lip to S-line (P<0.010), the interincisal angle (P<0.032) and the mandibular ́s plane (P<0.001). A statistical significant difference was shown between brachycephalic and dolichocephalic individuals: lower lip to E-line (P<0.001), upper lip to S-line (P<0.037), lower lip to S-line (P<0.001), interincisal angle (P<0.034) and the angle between the mandibular ́s plane (P<0.001). Lip soft tissue projection will depend on the population studied; we found some significant differences when compared with the cephalometric norms.


El objetivo del presente estudio fue examinar la proyección labial en pacientes braquicéfalos, mesocéfalos y dolicocéfalos mexicanos al igual que analizar la relación entre la protrusión dental y la posición labial, identificar si existe proyección labial de los tejidos blandos y determinar las características predominantes en el estudio. Un total de 120 radio grafías laterales de cráneo se seleccionaron de manera aleatoria de pacientes entre 16-25 años. Los datos angulares y lineales se identificaron, los valores de la proyección labial superior e inferior con respecto a línea línea-E de Ricketts, línea-S de Steiner y línea-VV de Arnett fueron recolectados, los valores angulares a analizar fueron el ángulo nasolabial, el plano mandibular y el ángulo interincisal al igual que el surco mentolabial. Se usó la prueba T de Student para obtener la significancia. Una diferencia significativa se observó entre pacientes mesocéfalos y braquicéfalos en el plano mandibular con Frankfort (P <0.001). Entre dolicocéfalos y meso céfalos diferencias significativas se observaron en el labio inferior a línea-E (P <0.031), labio inferior a S (P <0.010), ángulo interincisal (P <0.032) y el plano mandibular (P <0.001). Diferencias significativas se observaron entre pacientes braquicéfalos y dolicocéfalos: labio inferior a línea-E (P <0.001), labio superior a línea-S (P <0.037), labio inferior a línea-S (P <0.001), ángulo interincisal (P < 0.034) y el plano mandibular (P <0.001). La proyección labial depende de la población y se pueden observar algunas diferencias significativas al ser comparadas con la norma cefalométrica.


Asunto(s)
Adolescente , Adulto , Humanos , Adulto Joven , Craneosinostosis/complicaciones , Labio/anomalías , Cefalometría
20.
Invest. clín ; 57(4): 321-329, dic. 2016. tab
Artículo en Español | LILACS | ID: biblio-841123

RESUMEN

Se evaluó la eficacia antimicrobiana de las nanopartículas de plata (NPsAg) incorporadas al adhesivo (primer) colocado en el esmalte dental adyacente a la aparatología ortodóncica fija (brackets). Se realizó un estudio experimental in vitro en 40 premolares, los cuales se dividieron en dos grupos con brackets, uno cementado con primer convencional y otro adicionado con NPsAg; se colocaron en medios de cultivo, previamente inoculados con Streptococcus mutans, y se tomaron muestras para hacer cultivos y conteo de unidades formadoras de colonias (UFC) al día 1, 15 y 30. Se observó una disminución de la presencia de Streptococcus mutans en las muestras a los 15 días de colocado el primer con la agregación de nanopartículas, aunque tal efecto se redujo a los 30 días. Esta reducción del efecto de las nanopartículas puede deberse a la inexistencia de limpieza mecánica, lo cual favoreció la agregación bacteriana sobre el biofilm, afectando su efecto antimicrobiano. Esto sugiere la necesidad de realizar estudios in vivo que permitan observar el comportamiento de los biomateriales en el medio bucal. Las NPsAg agregadas al primer resultan una herramienta eficaz para prevenir la desmineralización del esmalte alrededor de la aparatología ortodóncica fija.


The antimicrobial efficacy of the silver nanoparticles (NPsAg), incorporated into the adhesive (primer) placed in the enamel adjacent to fixed orthodontic appliances (brackets), was evaluated. An experimental study was performed on 40 premolars in vitro, which were divided into two groups with brackets, one cemented with conventional primer and another added with NPsAg, placed in culture media previously inoculated with Streptococcus mutans, and sampled for culturing and counting colony forming units (UFC) on days 1, 15 and 30. A decrease in the presence of Streptococcus mutans in the samples after 15 days with nanoparticle aggregation was observed, and a reduction in the effect of said nanoparticles after 30 days. This reduction of the nanoparticles effects can be due to the absence of mechanical cleaning, which favored the bacterial aggregation on the biofilm, affecting its antimicrobial effect. This suggest the need for realizing studies in “vivo” which will allow the observation of the behavior of the biometals on the buccal medium. The NPsAg added to the primer are an effective tool to prevent the demineralization of the enamel around the fixed orthodontic appliances.


Asunto(s)
Aparatos Ortodóncicos/microbiología , Plata , Cementos Dentales , Nanopartículas del Metal , Antibacterianos/farmacología , Técnicas In Vitro , Estudios Transversales
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