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1.
Sci Data ; 11(1): 225, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383609

RESUMEN

Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Trait-based approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families.


Asunto(s)
Ecosistema , Pradera , Plantas , Biodiversidad , Perú , Clima , Altitud , Incendios
2.
Scientifica (Cairo) ; 2023: 8846387, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38146491

RESUMEN

The cytotoxic properties of two extracts from Chenopodium quinoa Willd. and three synthetic sapogenins were evaluated in different cancer cell lines (A549, SH-SY5Y, HepG2, and HeLa) to investigate their cytotoxic effects and determine if these cell lines activate the caspase pathway for apoptosis in response to saponin and sapogenin treatment. The saponin extracts were isolated from the agro-industrial waste of Chenopodium quinoa Willd., while the sapogenins were identified and quantitatively determined by High-Performance Liquid Chromatography (HPLC). Among these compounds, ursolic acid was the most active compound, with high IC50 values measured in all cell lines. In addition, hederagenin demonstrated higher caspase-3 activity than staurosporine in HeLa cells, suggesting an anti-cytotoxic activity via a caspase-dependent apoptosis pathway. HPLC analysis showed that the concentration of hederagenin was higher than that of oleanolic acid in ethanolic extracts of white and red quinoa. The ethanolic extracts of white and red quinoa did not show cytotoxic activity. On the other hand, the synthetic sapogenins such as ursolic acid, oleanolic acid, and hederagenin significantly decreased the viability of the four cell lines studied. Finally, by Caspase-3 assay, it was found that HeLa undergoes apoptosis during cell death because hederagenin produces a significant increase in PARP-1 hydrolysis in HeLa cells.

3.
ACS Omega ; 8(41): 37948-37957, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37867694

RESUMEN

Anticancer peptides are increasingly being considered as alternative treatments for cancer due to their potency, selectivity, and low toxicity. Previously, the peptide LfcinB (21-25)Pal showed in vitro anticancer effects against the Caco-2 colon cancer cell line (half-maximal inhibitory concentration (IC50): 86 µM). In this study, we developed modifications to the peptide sequence to increase its anticancer activity. Sequence modifications were made such as the inclusion of amino hexanoic acid (Ahx), N-terminal biotinylation, acetylation, and substitutions of Orn for Arg and/or d-Arg by l-Arg. The molecules were synthesized using manual solid-phase peptide synthesis (SPPS), and their synthetic feasibility (SAScore) ranged from 6.2 to 7.6. The chromatographic purities of the synthesized peptides were greater than 89%. We found that Ahx-RWQWRWQWR and RWQWRWQW-Orn showed activity against both Caco-2 and HT-29 cell lines and decreased IC50 values by approx. 50% in Caco-2 cells (IC50: 40 µM) when compared to the parent peptide RWQWRWQWR. Moreover, the modified peptides demonstrated lower hemolytic effects, with values <10% at 200 µg/mL. Toxicity was assessed using the Galleria mellonella model and the half-maximal lethal dose (LD50) for the best peptides was >100 mg/kg, indicating that their toxicity is classified as moderately toxic or lower. In contrast, cisplatin showed an LD50 of 13 mg/Kg. The designed anticancer peptides presented good in vitro activity and low toxicity, making them promising molecules for future drug development studies.

4.
Biomed Chromatogr ; 37(12): e5741, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37688464

RESUMEN

Matrix effect and sample pretreatment significantly affect the percentage recovery of peptides in biological matrices, affecting the method robustness and accuracy. To counteract this effect, an internal standard (IS) is used; however, in most cases this is not available, which limits the analytical method. It is important to identify short peptides that can be used as ISs in the quantification of peptides in biological matrices. In this study, doping peptides GHRP-4, GHRP-5, GHRP-6, Sermorelin (1-11), Sermorelin (13-20) and Sermorelin (22-29) were synthesized using solid-phase peptide synthesis. Treatment with human blood, trypsin and chymotrypsin was used to determine the stability of the peptides. Products were evaluated using the high-performance liquid chromatography-diode array detector (HPLC-DAD) method. The analytical methodology and sample pretreatment were effective for the analysis of these molecules. A unique profile related to protein binding and enzymatic stability of each peptide was established. GHRP-4, GHRP-6 and Sermorelin (22-29) can be considered as in-house ISs as they were stable to enzyme and blood treatment and can be used for the quantification of peptides in biological samples. Peptides GHRP-6 and Sermorelin (22-29) were used to analyse a dimeric peptide (26 [F] LfcinB (20-30)2 ) in four different matrices to test these peptides as in-house IS.


Asunto(s)
Pruebas de Química Clínica , Doping en los Deportes , Hormona Liberadora de Hormona del Crecimiento , Sustancias de Crecimiento , Péptidos/análisis , Humanos , Suero/química , Estabilidad Proteica , Análisis Químico de la Sangre/normas , Pruebas de Química Clínica/normas , Hormona Liberadora de Hormona del Crecimiento/análisis , Sustancias de Crecimiento/análisis
5.
R Soc Open Sci ; 10(6): 221493, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37325596

RESUMEN

The dimeric peptide 26[F]: (RRWQWRFKKLG)2-K-Ahx has exhibited a potent cytotoxic effect against breast cancer cell lines, with position 26 (F) being the most relevant for anti-cancer activity. In this investigation, six analogues of the 26[F] peptide were synthesized in which the 26th position was replaced by non-natural hydrophobic amino acids, finding that some modifications increased the resistance to proteolytic degradation exerted by trypsin or pepsin. Additionally, these modifications increased the cytotoxic effect against breast cancer cells and generated cell death mediated by apoptosis pathways, activating caspases 8 and 9, and did not compromise the integrity of the cytoplasmic membrane. Finally, it was found that the modified peptides have a broad spectrum of action, since they also have a cytotoxic effect against the HeLa human cervical cancer cell line. Peptide 26[F] was inoculated in mice by ip administration and the lethal dose 50 (LD50) was between 70 and 140 mg kg-1. While for the 26[1-Nal]: (RRWQWR-1-Nal-KKLG)2-K-Ahx peptide, a dose-response test was performed, and the survival rate was 100%. These results suggested that these peptides are safe in this animal model and could be considered as promissory to develop a treatment against breast cancer.

6.
Rev. peru. biol. (Impr.) ; 30(2)abr. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1515495

RESUMEN

Se describe una especie nueva del género Charinus Simon, 1892, procedente del distrito Santa Teresa (1436 -1511 m de altitud), en La Convención, Cusco, Perú, la cual es la tercera para dicha región y la quinta para este país sudamericano. Su aspecto general y los gonópodos de la hembra son muy parecidos a los de Charinus longitarsus Armas & Palomino-Cardenas, 2016 y C. yanatile Palomino-Cardenas & Armas, 2022, también del Cusco; pero se diferencia de ambas por presentar en la distitibia del cuarto par de patas 16 tricobotrios, en lugar de 14; además, C. longitarsus posee 30 tarsómeros en las patas I (43 en la especie nueva); mientras que en C. yanatile, el tubérculo ocular es más grande y el tarsómero 1 del primer par de patas es más largo que los dos siguientes juntos (en la especie nueva es más corto). También se enmienda la descripción de los gonópodos femeninos de C. longitarsus y se incluye una clave taxonómica para la identificación de las especies peruanas de Charinus.


A new species of the genus Charinus Simon, 1892 is described from Santa Teresa District (1436 -1511 m of altitude), La Convención, Cusco, Peru, being this the third Charinus species from this region and the fifth one for this South American country. Its general feature and female gonopods greatly resembles Charinus longitarsus Armas & Palomino-Cardenas, 2016, and C. yanatile Palomino-Cardenas & Armas, 2022, from Cusco, too; but it differs from them by having 16 instead of 14 trichobothria in the distitibia of leg IV; on the other hand, in C. longitarsus the leg I has 30 tarsomeres (43 in the new species); whereas C. yanatiles has larger median ocular tubercle and the first tarsomere of leg I is longer than tarsomeres 1+2 joined. Also, the description of the female gonopods of C. longitarsus is emended and a taxonomic key for the identification of the Peruvian species of Charinus is given.

7.
ACS Omega ; 8(2): 2712-2722, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36687035

RESUMEN

Breast cancer is one of the main causes of premature death in women; current treatments have low selectivity, generating strong physical and psychological sequelae. The palindromic peptide R-1-R (RWQWRWQWR) has cytotoxic activity against different cell lines derived from cancer and selectivity against noncancerous cells. To determine if changes in the charge/length of this peptide increase its activity, six peptides were obtained by SPPS, three of them with addition of Arg at the N, C-terminal or both and three with deletion of Arg at the N, C-terminal or both. The cytotoxic and selective activities were evaluated against MCF-7, MDA-MB-231, and MCF-12 cell lines and fibroblast primary cell culture, evidencing that the RR-1-R peptide with the inclusion of Arg in the N-terminal end maintained selectivity and increased cytotoxicity against lines derived from breast cancer. The effect of this addition regarding the type of induced cell death was evaluated by flow cytometry, showing very low rates of necrosis and a significant majority of apoptotic events with activation of both Caspase 8 and Caspase 9. This work allowed us to find a modification that generates a peptide with greater cytotoxic effects and can be considered a promising molecule for other approaches to improve anticancer peptides.

8.
FASEB J ; 35(7): e21747, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34151467

RESUMEN

We tested the hypothesis that the cognitive impairment associated with inflammatory pain may result from dysregulation of the top-down control of locus ceruleus's (LC) activity by the medial prefrontal cortex (mPFC). Injection of complete Freund's adjuvant (CFA) served as a model for inflammatory pain. The CFA injection decreased the thermal thresholds in both sexes but only the male mice showed increased anxiety-like behavior and diminished cognition, while the females were not affected. Increased calcium fluorescence, a marker for neuronal activity, was detected by photometry in the mPFC of males but not in females with CFA. Next, while chemogenetic inhibition of the projections from the mPFC to the LC improved the object recognition memory of males with pain, the inhibition of the mPFC to LC pathway in female mice produced anxiolysis and spatial memory deficits. The behavior results prompted us to compare the reciprocal innervation of mPFC and LC between the sexes. We used an anterograde transsynaptic tagging technique, which relies on postsynaptic cre transfer, to assess the innervation of LC by mPFC efferents. The males showed a higher rate of postsynaptic cre transfer into LC neurons from mPFC efferents than the females. And vice versa, a retrograde tracing experiment demonstrated that LC to mPFC projection neurons were more numerous in females when compared to males. In conclusion, we provide evidence that subtle differences in the reciprocal neuronal circuit between the LC and mPFC may contribute to sex differences associated with the adverse cognitive effects of inflammatory pain.


Asunto(s)
Inflamación/fisiopatología , Locus Coeruleus/fisiopatología , Dolor/fisiopatología , Corteza Prefrontal/fisiopatología , Animales , Femenino , Masculino , Trastornos de la Memoria/fisiopatología , Ratones , Neuronas/fisiología , Caracteres Sexuales , Memoria Espacial/fisiología
9.
Zootaxa ; 4981(2): 331356, 2021 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-34186717

RESUMEN

The tribe Otteiini is a group of cave crickets, that were believed only to inhabit the Greater Antilles (Cuba, Cayman Islands, and Hispaniola). However, when reviewing and studying similar cave crickets in Mexico, their relationship was proven with island taxa, expanding their distribution to the continental area, from the Yucatan Peninsula to the Gulf and Northeast of Mexico. Herein, the genus Paracophus is divided, and three additional genera are described: Hubbellcophus n. gen., Venegascophus n. gen. and Hortacophus n. gen. Also, two additional species for Paracophus are described (P. victoriensis n. sp. and P. velazquezi n. sp.). Diagnoses for all genera and dichotomous keys for genera and species are provided. Finally, the taxonomic relationships between the insular and continental taxa of the tribe are discussed, and the different taxonomic placements they had over time, with some genera located in Phalangopsinae and Luzarinae (Phalangopsidae) and Pentacentrinae (Gryllidae).


Asunto(s)
Gryllidae/clasificación , Distribución Animal , Animales , Cuevas , México , Indias Occidentales
10.
Zootaxa ; 4970(3): 515532, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-34186882

RESUMEN

In this contribution to the American Field and Short-tail crickets, two new species from the continental and insular area of Colombia are described. Anurogryllus (Urogryllus) edithsantosum n. sp. from the Meta department, is more related to some Caribbean species, and its genital structure fits the morphological current definition of the subgenus Urogryllus, although it has pseudepiphallic median lophi covered with hairs, as it happens in the species of the subgenus Pilosogryllus. The same way, Gryllus (Gryllus) providiensis n. sp. from Providencia Island, San Andres Archipelago is described, this new species has thick hairs on the pronotum as Gryllus (Gryllus) assimilis (widely distributed in America), as well as the color pattern of the cephalic capsule; but the new species is smaller in size, and has a particular organization in the harp veins of the tegmina, which only resembles Gryllus (Gryllus) marchena from the Galapagos Archipelago (Ecuador), from which it differs markedly in its morphology. Finally, the status of the Gryllus species, distributed in Latin America and the Caribbean, is reviewed, and it is recorded which species have acoustic records, and from here we start with the review of this peculiar genus in Latin America.


Asunto(s)
Gryllidae/anatomía & histología , Gryllidae/clasificación , Animales , Colombia , Clima Tropical
11.
Int. j interdiscip. dent. (Print) ; 14(1): 95-99, abr. 2021. tab
Artículo en Español | LILACS | ID: biblio-1385195

RESUMEN

RESUMEN: Introducción: Las restauraciones de caries proximales en dientes primarios son complejas de realizar, siendo fundamental la correcta realización de la técnica para la restitución de la dentición funcional. La resina compuesta y vidrio ionómero modificado con resina son de los materiales más utilizados en la actualidad, debido a sus propiedades estéticas y de adhesión, pero aún no está clara la efectividad de un material por sobre otro. Métodos: Para responder la pregunta se realizó una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. Resultados y conclusiones: Identificamos nueve revisiones sistemáticas que en conjunto incluyeron siete estudios primarios, de los cuales, cinco corresponden a ensayos aleatorizados. Concluimos que el uso de resina compuesta en caries proximales cavitadas de dientes primarios podría resultar en poca o nula diferencia en el fracaso de la restauración, pero la certeza de la evidencia es baja. Además el uso de resina compuestas probablemente aumente el riesgo de caries secundaria. Además, no se encontraron estudios que evaluaran la retención de la restauración.


ABSTRACT: Introduction: Ensure an adequate interproximal caries restorations in primary teeth are essential for the restoration of functional dentition, but the technique is sensitive. Composite resin and resin-modified glass ionomer are among the most widely used materials today, due to their aesthetic and adhesion properties, but the effectiveness of one material over another is not yet clear. Methods: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. Results and conclusions: We identified nine systematic reviews including seven studies overall, of which five were randomized trials. The use of composite resin may improve the failure of the restorations but the evidence is low. The use of composite resin probably improves the risk of secondary caries. No studies were found evaluating retention of the restoration.


Asunto(s)
Humanos , Resinas Compuestas/uso terapéutico , Caries Dental/terapia , Cementos de Ionómero Vítreo/uso terapéutico
12.
Int. j interdiscip. dent. (Print) ; 13(3): 176-180, dic. 2020. tab
Artículo en Español | LILACS | ID: biblio-1385169

RESUMEN

RESUMEN: Introducción: La pulpotomía parcial se utiliza para el tratamiento de caries con exposición pulpar en dientes permanentes inmaduros. El agregado de trióxido mineral (MTA) ha sido propuesto como uno de los biomateriales de elección para el tratamiento, pero existe incertidumbre en relación a su efectividad comparado con la del hidróxido de calcio. Métodos: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. Resultados y conclusiones: Encontramos cinco revisiones sistemáticas, que incluyeron tres estudios primarios, de los cuales todos corresponden a ensayos aleatorizados. Concluimos que la pulpotomía parcial con agregado de trióxido mineral (MTA) podría resultar en poca o nula diferencia en la tasa de éxito comparado a la pulpotomía parcial con hidróxido de calcio, pero la certeza de la evidencia es baja.


ABSTRACT: Introduction: Partial pulpotomy is the treatment of choice following carious pulp exposure in immature permanent teeth. Mineral trioxide aggregate (MTA) has been suggested as the biomaterial first option for treatment, but there is still uncertainty regarding its effectiveness compared to calcium hydroxide. Methods: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. Results and conclusions: We identified five systematic reviews including three studies overall, of which all were randomized trials. We conclude that partial pulpotomy with mineral trioxide aggregate (MTA) may make little or no difference to success rate compared to partial pulpotomy with calcium hydroxide, however, the certainty of the evidence has been assessed as low.


Asunto(s)
Humanos , Pulpotomía/métodos , Hidróxido de Calcio/administración & dosificación , Silicatos/administración & dosificación , Compuestos de Calcio/administración & dosificación , Compuestos de Aluminio/administración & dosificación , Caries Dental/terapia , Óxidos , Toma de Decisiones , Combinación de Medicamentos
13.
Int. j interdiscip. dent. (Print) ; 13(3): 212-216, dic. 2020. tab
Artículo en Español | LILACS | ID: biblio-1385155

RESUMEN

RESUMEN: Introducción: En dentición primaria, la pulpotomía con formocresol ha sido convencionalmente utilizada para el tratamiento de caries cercanas a la pulpa. Sin embargo, la seguridad de este material ha sido cuestionada. Por otro lado, el biodentine ha sido propuesto como un biomaterial sustituto bioactivo de la dentina, pero no está clara su efectividad. Métodos: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y una tabla GRADE para el resumen de los resultados. Resultados y conclusiones: Identificamos tres revisiones sistemáticas que en conjunto incluyeron dos estudios primarios, ambos correspondientes a ensayos aleatorizados. Concluimos que no se puede establecer con claridad si biodentine comparado con formocresol aumenta el éxito clínico y el éxito radiográfico en pulpotomía en pacientes con dentición primaria, debido a que la certeza de la evidencia existente ha sido evaluada como muy baja.


ABSTRACT: Introduction: Pulpotomy with formocresol is the main treatment protocol following carious pulp exposure in primary teeth, but many concerns have been raised regarding its safety. Biodentine has been proposed as a bioactive dentine substitute, but there is still uncertainty regarding its effectiveness. Methods: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. Results and conclusions: We identified three systematic reviews including two studies overall, of which both were randomized trials. We are uncertain whether biodentine compared to formocresol for pulpotomy improves clinical and radiographic success, as the certainty of the evidence has been assessed as very low.


Asunto(s)
Humanos , Pulpotomía/métodos , Silicatos/uso terapéutico , Compuestos de Calcio/uso terapéutico , Formocresoles/uso terapéutico , Irrigantes del Conducto Radicular/uso terapéutico , Resultado del Tratamiento
14.
Pain ; 161(8): 1861-1871, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32701845

RESUMEN

We investigated the contribution of nucleus locus ceruleus (LC) to the development of pain-associated affective behavior. Mice of both sexes were subjected to sciatic nerve cuffing, a model of peripheral nerve injury, and monitored for 45 days. Although the thermal and mechanical thresholds were equally decreased in both males and females, only the male mice developed anxiodepressive-like behavior, which was complemented by suppressed hippocampal neurogenesis. Furthermore, the LC activity was lower in males when compared with females subjected to sciatic cuffing. Next, we used a chemogenetic approach to modulate the activity of LC projections to the dentate gyrus of the hippocampus in females without cuffs and in males with sciatic cuffs. Sustained inhibition of the LC projections to the dentate gyrus for 15 days induced anxiodepressive-like behavior and reduced the hippocampal neurogenesis in females. Activation of the LC projections to the dentate gyrus for 15 days prevented the development of anxiodepressive-like behavior and increased the hippocampal neurogenesis in males with cuffs. In sum, we demonstrated that the LC projections to the hippocampus link the sensory to the affective component of neuropathic injury and that the female mice are able to dissociate the nociception from affect by maintaining robust LC activity. The work provides evidence that sex differences in LC response to pain determine the sex differences in the development of pain phenotype.


Asunto(s)
Nervio Ciático , Caracteres Sexuales , Animales , Femenino , Hipocampo , Masculino , Ratones , Ratones Endogámicos C57BL , Neurogénesis
15.
Int J Mol Sci ; 21(12)2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32604743

RESUMEN

The effect on the cytotoxicity against breast cancer cell lines of the substitution of 26Met residue in the sequence of the Bovine Lactoferricin-derived dimeric peptide LfcinB (20-30)2: (20RRWQWRMKKLG30)2-K-Ahx with amino acids of different polarity was evaluated. The process of the synthesis of the LfcinB (20-30)2 analog peptides was similar to the original peptide. The cytotoxic assays showed that some analog peptides exhibited a significant cytotoxic effect against breast cancer cell lines HTB-132 and MCF-7, suggesting that the substitution of the Met with amino acids of a hydrophobic nature drastically enhances its cytotoxicity against HTB-132 and MCF-7 cells, reaching IC50 values up to 6 µM. In addition, these peptides have a selective effect, since they exhibit a lower cytotoxic effect on the non-tumorigenic cell line MCF-12. Interestingly, the cytotoxic effect is fast (90 min) and is maintained for up to 48 h. Additionally, through flow cytometry, it was found that the obtained dimeric peptides generate cell death through the apoptosis pathway and do not compromise the integrity of the cytoplasmic membrane, and there are intrinsic apoptotic events involved. These results show that the obtained peptides are extremely promising molecules for the future development of drugs for use against breast cancer.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Apoptosis , Neoplasias de la Mama/patología , Lactoferrina/farmacología , Fragmentos de Péptidos/farmacología , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Bovinos , Proliferación Celular , Femenino , Humanos , Células Tumorales Cultivadas
16.
RSC Adv ; 10(30): 17593-17601, 2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35515633

RESUMEN

The cytotoxic effect against the breast cancer cell line MDA-MB-468 of the palindromic peptide LfcinB (21-25)Pal: 1RWQWRWQWR9 and its analogous peptides, obtained via alanine scanning, was evaluated. The results indicate that the palindromic peptide exhibited a concentration-dependent cytotoxic effect against this cell line. The cytotoxic effect of the palindromic peptide was fast and selective and was sustained for up to 48 h of treatment. MDA-MB-468 cells treated with the palindromic peptide exhibited severe cellular damage, acquiring rounded forms and shrinkage, a behavior typical of apoptotic events. The analogous peptides exhibited fewer cytotoxic effects than the original palindromic peptide, suggesting that the substitution of any amino acid with alanine diminishes the cytotoxic effect. The Arg and Trp residues proved to be the most relevant for the cytotoxic effect; the analogous peptides with substitutions of Trp with Ala did not induce a change in cellular morphology, while analogous peptides with substitutions of Arg or Gln with Ala induced cellular damage. Also, neither the palindromic peptide nor its analogues exerted a significant cytotoxic effect on normal fibroblasts, indicating that the peptides had a selective cytotoxic effect on cancerous cells. The peptide LfcinB (21-25)Pal, and its analogues exhibited antibacterial activity against E. coli and S. aureus strains and a selective cytotoxic effect against the breast cancer cell line MDA-MB-468.

17.
Neurobiol Stress ; 10: 100163, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31193505

RESUMEN

Ensembles of principal neurons in the basolateral amygdala (BLA) generate the initial engrams for fear memories, while projections from the BLA to the medial prefrontal cortex (mPFC) are essential for the encoding, transfer and storage of remote fear memories. We tested the effects of chronic pain on remote fear memories in mice. Male mice underwent classic fear conditioning by pairing a single tone (conditional stimulus, CS) with a single electric foot shock (unconditional stimulus, US). Sciatic nerve constriction was used to induce neuropathic pain at various time points before or after the fear conditioning. The mice with sciatic nerve cuffs implanted 48 h after the fear conditioning showed an increased freezing response to CS when compared to mice without cuffs or when compared to mice in which the nerve cuffing was performed 48 h before the fear conditioning. The enhancing effect of pain on consolidated fear memory was further tested and mice in which the nerve cuffing was performed 14 days after the fear conditioning also showed an increased fear response when tested 56 days later. We used immunostaining to detect morphological changes in the BLA that could suggest a mechanism for the observed increase in fear response. We found an increased number of calbindin/parvalbumin positive neurons in the BLA and increased perisomatic density of GAD65 on projection neurons that connect BLA to mPFC in mice with nerve cuffs. Despite the strong increase of c-Fos expression in BLA and mPFC that was induced by fear recall, neither the BLA to mPFC nor the mPFC to BLA projection neurons were activated in mice with nerve cuffs. Furthermore, non-injured mice had an increased fear response when BLA to mPFC projections were inhibited by a chemogenetic method. In conclusion, this study provides evidence that persistent pain has a significant impact on consolidated fear memories. Very likely the underlying mechanism for this phenomenon is increased inhibitory input onto the BLA to mPFC projection neurons, possibly from neurons with induced parvalbumin expression. Conceivably, the increased fear response to consolidated fear memory is a harbinger for the later development of anxiety and depression symptoms associated with chronic pain.

18.
Br J Ophthalmol ; 103(10): 1511-1517, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30602450

RESUMEN

BACKGROUND/AIM: Blood flow deficiencies of the retinal and retrobulbar circulations have been previously reported in open-angle glaucoma (OAG) and other eye diseases. Herein we investigated the effects of image brightness and contrast dynamic altering stimuli (DAS) when viewing a video content on ocular blood flow, intraocular pressure (IOP) and ocular perfusion pressure (OPP) in OAG and healthy subjects. METHODS: Thirty-five subjects, 25 with OAG (mild to moderate) and 10 healthy controls, were evaluated for blood pressure, IOP, OPP and retinal capillary blood flow before, immediately after, 30 min after and 60 min after using ReviView (a dichoptic video goggles device), which stimulates one eye with a DAS video image that is brighter and with greater contrast than the fellow eye (duration of exposure 30 min). Differences between each subject's eyes and between OAG and healthy subjects were evaluated using repeated-measures analysis of variance with p<0.05 considered statistically significant. RESULTS: All subjects demonstrated a significant increase in OPP in both eyes immediately following viewing. In all DAS eyes, retinal capillary blood flow rose immediately after stimulation and remained elevated for an hour postviewing. Viewing DAS increased retinal blood flow compared with control eyes (p=0.0014, 0.0135 superiorly and p=0.0094, 0.0001 inferiorly, at 30 and 60 min, respectively). OAG eyes had a significant reduction in the number of dormant retinal capillaries (p=0.0174), while healthy eyes demonstrated a larger increase in retinal capillary blood flow (p=0.0006 and p=0.0093 at 60 min, superior and inferior, respectively) following DAS viewing. CONCLUSION: Viewing DAS video for 30 min using ReviView increased retina blood flow both in healthy subjects and in patients with OAG. TRIAL REGISTRATION NUMBER: NCT02959593.


Asunto(s)
Presión Sanguínea/fisiología , Glaucoma de Ángulo Abierto/fisiopatología , Presión Intraocular/fisiología , Vasos Retinianos/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo/fisiología , Capilares/fisiología , Femenino , Hemodinámica , Humanos , Flujometría por Láser-Doppler , Masculino , Persona de Mediana Edad , Flujo Sanguíneo Regional/fisiología , Tonometría Ocular
19.
RSC Adv ; 9(36): 20497-20504, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35515557

RESUMEN

The cytotoxic effect of the tetrameric peptide LfcinB (20-25)4 against breast cancer cell line ATCC® HTB-22™ (MCF-7) was evaluated. The tetrameric peptide exhibited a concentration-dependent cytotoxic effect against MCF-7 cancer cells. The peptide at 22 µM had the maximum cytotoxic effect against MCF-7 cancer cells, reducing their cell viability to ∼20%. The cytotoxic effect of the tetrameric peptide against MCF-7 cells was sustained for 24 hours. Furthermore, the tetrameric peptide did not exhibit a significant cytotoxic effect against the non-tumorogenic trophoblastic cell line, which confirms their selectivity for breast cancer cell lines. The MCF-7 cells treated at 12.2 µM for 1 h exhibited morphological changes characteristic of apoptosis, such as rounded forms and cellular shrinkage. Furthermore, this peptide induces severe cellular damage to MCF-7 cells, mitochondrial membrane depolarization, and increase of cytoplasmic calcium concentration. Our results suggest that it has a significant selective cytotoxic effect against MCF-7 cells, which may be mainly associated with the apoptotic pathway. This peptide, which contains the RRWQWR motif, could be considered to be a promising candidate for developing therapeutic agents for the treatment of breast cancer.

20.
Pediatr Pulmonol ; 49(3): 269-76, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23401345

RESUMEN

INTRODUCTION: Respiratory syncytial virus (RSV) is one of the leading causes of acute lower respiratory infection (ALRI) in infants and young children. Although ALRI is a major public health problem in developing countries located in tropical areas, studies about RSV epidemiology in these regions are scarce. METHODS: In a retrospective cohort study, we investigated the epidemiology and predictive variables that reflect disease severity and mortality in young children hospitalized with ALRI due to RSV in Colombia, South-America, during a 2-year period (2009-2011). RESULTS: Of a total of 6,344 children with a diagnosis of ALRI, we selected 2,147 (33.8%) that were positive for RSV. After controlling for pre-existing conditions, we found that independent predictors of severe disease in our population included age <6 months (RR 2.01; CI 95% 1.70-2.38; P < 0.001), prematurity (RR 1.61; CI 95% 1.20-2.17; P = 0.001), congenital heart disease (RR 2.03; CI 95% 1.16-3.54; P = 0.013), and mixed RSV-adenovirus infection (RR 2.09; CI 95% 1.60-2.73; P < 0.001). Multivariate analysis identified that cancer (RR 31.60; CI 95% 5.97-167.13; P < 0.001) is a predictor of mortality in our RSV-infected pediatric population independently of age and other co-morbidities. CONCLUSIONS: RSV is an important cause of ALRI in infants and young children living in tropical regions, especially during the rainy season. The identified predictors of severe disease and mortality should be taken into account when planning interventions to reduce the burden of ALRI in young children living in these regions.


Asunto(s)
Bronquiolitis Viral/mortalidad , Infecciones por Virus Sincitial Respiratorio/mortalidad , Infecciones por Adenoviridae/epidemiología , Factores de Edad , Bronquiolitis Viral/epidemiología , Bronquiolitis Viral/fisiopatología , Preescolar , Estudios de Cohortes , Coinfección/epidemiología , Colombia/epidemiología , Cardiopatías Congénitas/epidemiología , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Unidades de Cuidado Intensivo Pediátrico/estadística & datos numéricos , Enfermedades Renales/epidemiología , Análisis Multivariante , Neoplasias/epidemiología , Terapia por Inhalación de Oxígeno/estadística & datos numéricos , Análisis de Regresión , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/fisiopatología , Estudios Retrospectivos , Factores de Riesgo , Estaciones del Año , Índice de Severidad de la Enfermedad
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