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1.
Pathobiology ; 90(5): 333-343, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37040716

RESUMEN

INTRODUCTION: Genomic variants of the human papillomavirus type 16 (HPV16) are thought to play differential roles in the susceptibility to head and neck squamous cell carcinomas (HNSCC) and its biological behaviour. This study aimed to establish the prevalence of HPV16 variants in an HNSCC cohort and associate them with clinical pathological characteristics and patient survival. METHODS: We retrieved samples and clinical data from 68 HNSCC patients. DNA samples were available from tumour biopsy at the time of the primary diagnosis. Targeted next-generation sequencing was used to obtain whole-genome sequences, and variants were established based on phylogenetic classification. RESULTS: 74% of samples clustered in lineage A, 5.7% in lineage B, 2.9% in lineage C, and 17.1% in lineage D. Comparative genome analysis revealed 243 single nucleotide variations. Of these, one hundred were previously reported, according to our systematic review. No significant associations with clinical pathological variables or patient survival were observed. The E6 amino acid variations E31G, L83V, and D25E and E7 N29S, associated with cervical cancer, were not observed, except for N29S in a single patient. CONCLUSION: These results provide a comprehensive genomic map of HPV16 in HSNCC, highlighting tissue-specific characteristics which will help design tailored therapies for cancer patients.

2.
Biomacromolecules ; 23(10): 4041-4052, 2022 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-36173245

RESUMEN

Herpes simplex virus type 1 (HSV-1) is a persistent human pathogen, and the emergence of strains resistant to Acyclovir (ACV, reference drug) shows the urgency to develop new treatments. We report the antiherpetic mechanism of the action of lasiodiplodan (LAS-N, (1 → 6)-ß-d-glucan) and its sulfonated derivative (LAS-S3) in vitro and in vivo. LAS-S3 showed anti-HSV-1 action with high selectivity indices for HSV-1 KOS (88.1) and AR (189.2), sensitive and resistant to ACV, respectively. LAS-S3 inhibited >80% of HSV-1 infection in different treatment protocols (virucidal, adsorption inhibition, and post-adsorption effects), even at low doses, and showed a preventive effect and DNA and protein synthesis inhibition. The antiherpetic effect was confirmed in vivo by the cosmetic LAS-S3-CRÈME decreasing cutaneous lesions of HSV-1, including the AR strain. LAS-S3 possessed a broad-spectrum mechanism of action acting in the early and post-adsorption stages of HSV-1 infection, and LAS-S3-CRÈME is a potential antiherpetic candidate for patients infected by HSV-1-resistant strains.


Asunto(s)
Herpes Simple , Herpesvirus Humano 1 , Aciclovir/farmacología , Aciclovir/uso terapéutico , Antivirales/farmacología , Glucanos/farmacología , Herpes Simple/tratamiento farmacológico , Humanos
3.
Int J Mol Sci ; 23(20)2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36293226

RESUMEN

The study of human papillomavirus (HPV)-induced carcinogenesis uses multiple in vivo mouse models, one of which relies on the cytokeratin 14 gene promoter to drive the expression of all HPV early oncogenes. This study aimed to determine the HPV16 variant and sublineage present in the K14HPV16 mouse model. This information can be considered of great importance to further enhance this K14HPV16 model as an essential research tool and optimize its use for basic and translational studies. Our study evaluated HPV DNA from 17 samples isolated from 4 animals, both wild-type (n = 2) and HPV16-transgenic mice (n = 2). Total DNA was extracted from tissues and the detection of HPV16 was performed using a qPCR multiplex. HPV16-positive samples were subsequently whole-genome sequenced by next-generation sequencing techniques. The phylogenetic positioning clearly shows K14HPV16 samples clustering together in the sub-lineage A1 (NC001526.4). A comparative genome analysis of K14HPV16 samples revealed three mutations to the human papillomaviruses type 16 sublineage A1 representative strain. Knowledge of the HPV 16 variant is fundamental, and these findings will allow the rational use of this animal model to explore the role of the A1 sublineage in HPV-driven cancer.


Asunto(s)
Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , Ratones , Animales , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Queratina-14/genética , Filogenia , Neoplasias del Cuello Uterino/genética , Papillomavirus Humano 16 , Papillomaviridae/genética , Carcinogénesis/genética , Oncogenes
4.
Molecules ; 27(19)2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36235216

RESUMEN

The search for less expensive and viable products is always one of the challenges for research development. Commonly, the synthesis of coordination compounds involves expensive ligands, through expensive and low-yield routes, in addition to generating toxic and unusable residues. In this work, the organic ligand used is derived from the resin of a reforestation tree, Pinus elliottii var. elliottii. The synthesis method used Pinus resin and an aqueous solution of vanadium(III) chloride at a temperature of 80 °C. The procedure does not involve organic solvents and does not generate toxic residues, thus imparting the complex formation reaction a green chemistry character. The synthesis resulted in an unprecedented oxovanadium(IV)-bis(abietate) complex, which was characterized by mass spectrometry (MS), chemical analysis (CHN), vibrational (FTIR) and electronic spectra (VISIBLE), X-ray diffraction (XRD), and thermal analysis (TG/DTA). Colorimetric studies were performed according to the CIELAB color space. The structural formula found, consisted of a complex containing two abietate ligands, [VO(C20H29O2)2]. The VO(IV)-bis(abietate) complex was applied against microorganisms and showed promising results in antibacterial and antifungal activity. The best result of inhibitory action was against the strains of Gram-positive bacteria S. aureus and L. monocytogenes, with minimum inhibitory concentration (MIC) values of 62.5 and 125 µmol L−1, respectively. For Gram-negative strains the results were 500 µmol L−1 for E. coli; and 1000 µmol L−1 for Salmonella enterica Typhimurium. Antifungal activity was performed against Candida albicans, where the MIC was 15.62 µmol L−1, and for C. tropicalis it was 62.5 µmol L−1. According to the MFC analysis, the complex presented, in addition to the fungistatic action, a fungicidal action, as there was no growth of fungi on the plates tested. The results found for the tests demonstrate that the VO(IV)-bis(abietate) complex has great potential as an antimicrobial and mainly antifungal agent. In this way, the pigmented ink with antimicrobial activity could be used in environments with a potential risk of contamination, preventing the spread of microorganisms harmful to health.


Asunto(s)
Antiinfecciosos , Antifúngicos , Antibacterianos/química , Antiinfecciosos/farmacología , Antifúngicos/química , Candida albicans , Cloruros , Escherichia coli , Ligandos , Pruebas de Sensibilidad Microbiana , Solventes , Staphylococcus aureus , Vanadio/farmacología
5.
Sensors (Basel) ; 21(10)2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-34065568

RESUMEN

The development of robotic solutions for agriculture requires advanced perception capabilities that can work reliably in any crop stage. For example, to automatise the tomato harvesting process in greenhouses, the visual perception system needs to detect the tomato in any life cycle stage (flower to the ripe tomato). The state-of-the-art for visual tomato detection focuses mainly on ripe tomato, which has a distinctive colour from the background. This paper contributes with an annotated visual dataset of green and reddish tomatoes. This kind of dataset is uncommon and not available for research purposes. This will enable further developments in edge artificial intelligence for in situ and in real-time visual tomato detection required for the development of harvesting robots. Considering this dataset, five deep learning models were selected, trained and benchmarked to detect green and reddish tomatoes grown in greenhouses. Considering our robotic platform specifications, only the Single-Shot MultiBox Detector (SSD) and YOLO architectures were considered. The results proved that the system can detect green and reddish tomatoes, even those occluded by leaves. SSD MobileNet v2 had the best performance when compared against SSD Inception v2, SSD ResNet 50, SSD ResNet 101 and YOLOv4 Tiny, reaching an F1-score of 66.15%, an mAP of 51.46% and an inference time of 16.44ms with the NVIDIA Turing Architecture platform, an NVIDIA Tesla T4, with 12 GB. YOLOv4 Tiny also had impressive results, mainly concerning inferring times of about 5 ms.

6.
Int J Mol Sci ; 22(20)2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34681671

RESUMEN

The infection of mammalian cells by enveloped viruses is triggered by the interaction of viral envelope glycoproteins with the glycosaminoglycan, heparan sulfate. By mimicking this carbohydrate, some anionic polysaccharides can block this interaction and inhibit viral entry and infection. As heparan sulfate carries both carboxyl and sulfate groups, this work focused on the derivatization of a (1→3)(1→6)-ß-D-glucan, botryosphaeran, with these negatively-charged groups in an attempt to improve its antiviral activity. Carboxyl and sulfonate groups were introduced by carboxymethylation and sulfonylation reactions, respectively. Three derivatives with the same degree of carboxymethylation (0.9) and different degrees of sulfonation (0.1; 0.2; 0.4) were obtained. All derivatives were chemically characterized and evaluated for their antiviral activity against herpes (HSV-1, strains KOS and AR) and dengue (DENV-2) viruses. Carboxymethylated botryosphaeran did not inhibit the viruses, while all sulfonated-carboxymethylated derivatives were able to inhibit HSV-1. DENV-2 was inhibited only by one of these derivatives with an intermediate degree of sulfonation (0.2), demonstrating that the dengue virus is more resistant to anionic ß-D-glucans than the Herpes simplex virus. By comparison with a previous study on the antiviral activity of sulfonated botryosphaerans, we conclude that the presence of carboxymethyl groups might have a detrimental effect on antiviral activity.


Asunto(s)
Antivirales/farmacología , Virus del Dengue/efectos de los fármacos , Herpesviridae/efectos de los fármacos , Ácidos Sulfónicos/química , beta-Glucanos/química , Animales , Antivirales/química , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Virus del Dengue/fisiología , Glucanos/química , Glucanos/farmacología , Herpesviridae/fisiología , Metilación , Células Vero , Internalización del Virus/efectos de los fármacos , beta-Glucanos/farmacología
7.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33669021

RESUMEN

The expression of p16 is a good surrogate of human papillomavirus (HPV) infection in HPV-associated cancers. The significance of p16 expression, HPV genotype and genera in the outcome of patients with HPV-associated cervical cancer (CC) is unclear. Our aim is to ascertain the prognostic significance of these factors. Data from 348 patients (median age: 47.5 years old) with CC, diagnosed in two referral centers, were retrospectively collected. Advanced disease (FIGO2018 IB2-IV) was present in 68% of patients. A single HPV genotype was identified in 82.8% of patients. The most common HPVs were HPV16 (69%) and HPV18 (14%). HPV genera reflected this distribution. HPV16 tumors presented at an earlier stage. P16 was negative in 18 cases (5.2%), 83.3% of which were squamous cell carcinomas. These cases occurred in older patients who tended to have advanced disease. In the univariate analysis, HPV16 (HR: 0.58; p = 0.0198), α-9 genera (HR: 0.37; p = 0.0106) and p16 overexpression (HR: 0.54; p = 0.032) were associated with better survival. HPV16 (HR: 0.63; p = 0.0174) and α-9 genera (HR: 0.57; p = 0.0286) were associated with less relapse. In the multivariate analysis, only the International Federation of Gynecology and Obstetrics (FIGO) stage retained an independent prognostic value. HPV16, α-9 genera and p16 overexpression were associated with better survival, although not as independent prognostic factors. Patients with p16-negative HPV-associated CC were older, presented with advanced disease and had worse prognosis.


Asunto(s)
Adenocarcinoma/metabolismo , Carcinoma de Células Escamosas/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/metabolismo , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/virología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/virología , Estudios de Cohortes , Femenino , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Estudios Retrospectivos , Centros de Atención Terciaria , Regulación hacia Arriba , Neoplasias del Cuello Uterino/mortalidad , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología , Adulto Joven
8.
J Cosmet Sci ; 72(3): 279-291, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35361316

RESUMEN

Taro mucilage, a hydrocolloid present in the rhizome of Colocasia esculenta (L.) Schott, was extracted and characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy, thermal analysis, and proximal composition. In addition, cosmetic formulations based on extracted mucilage were developed and studied. The mucilage presented a semicrystalline structure with high thermal stability, the presence of granules along its surface area, and good emulsifying activity. High physical-chemical stability was also found in the mucilage and the cosmetic formulations during storage. All cream samples presented pseudoplastic behavior, with a flow behavior index lower than 1, which is a desirable characteristic for cosmetics, as it improves its applicability. The mucilage demonstrates potential for application in cosmetic products, and its commercial use as an ingredient in cosmetics could be a strategic tool for the creation of a new product chain and adding value to the culture of Colocasia0 esculenta.


Asunto(s)
Colocasia , Cosméticos , Colocasia/química , Polisacáridos
9.
Mod Pathol ; 33(5): 893-904, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31844270

RESUMEN

Vulvar squamous cell carcinoma can be divided by human papillomaviruses (HPV) status into two distinct clinicopathological and molecular entities. New agents targeting the tumor surface expression of programmed cell death-1/programmed cell death-ligand-1 are becoming a therapeutic option in an increasing number of carcinomas. We evaluate CD274 (PD-L1), CDKN2A (p16), tumor protein p53 (TP53), and epidermal growth factor receptor (EGFR) immunoexpression in primary tumors, recurrences and lymph node metastases and its correlations with prognosis and HPV status. We report 93 cases of vulvar squamous cell carcinoma diagnosed between 2002 and 2016 with the description of their clinicopathological features and prognosis data. Immunohistochemistry for CD274, CDKN2A, TP53, and EGFR was performed on tissue microarrays collecting from primary tumor, recurrences and lymph node metastasis. Kaplan-Meier estimator and multivariable Cox regression analysis controlling for FIGO stage and age were used. Patients who underwent surgery had a superior overall survival (HR = 0.51, 95% CI = 0.26-0.99 p = 0.04). Lymph node metastasis size ≥5 mm was associated with an inferior overall survival (HR = 1.88, 95% CI = 1.22-2.92 p = 0.004). CDKN2A expression was correlated with an inferior rate of recurrent disease (p = 0.02). In high-risk HPV DNA+ vulvar squamous cell carcinomas patients with CDKN2A- carcinomas showed a significantly worse overall survival than women with CDKN2A+ tumors (56% vs.100%, p = 0.003). TP53 expression was associated with an increased rate of recurrent disease (p = 0.0005). CD274 expression was associated with lymph node metastasis (p = 0.04). In 16 patients the CD274, CDKN2A, TP53, and EGFR expression changed between primary tumors, recurrences and lymph node metastases during tumor progression. In conclusion, a significant percentage of vulvar squamous cell carcinoma has a heterogeneous biomarker expression during tumor progression. We highlight the importance of some of these markers to be used as prognostic biomarkers. This data brings new light to future treatment using targeted therapy to EGFR or CD274 to include retesting such biomarkers in recurrence and lymph nodes metastases.


Asunto(s)
Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/patología , Neoplasias de la Vulva/patología , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1/biosíntesis , Carcinoma de Células Escamosas/virología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/biosíntesis , Receptores ErbB/biosíntesis , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/epidemiología , Pronóstico , Proteína p53 Supresora de Tumor/biosíntesis , Neoplasias de la Vulva/virología
10.
Bioprocess Biosyst Eng ; 43(12): 2153-2163, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32627063

RESUMEN

Apple pomace was studied as a raw material for the production of xylitol and 2G ethanol, since this agroindustrial residue has a high concentration of carbohydrate macromolecules, but is still poorly studied for the production of fermentation bioproducts, such as polyols. The dry biomass was subjected to dilute-acid hydrolysis with H2SO4 to obtain the hemicellulosic hydrolysate, which was concentrated, detoxified and fermented. The hydrolyzate after characterization was submitted to submerged fermentations, which were carried out in Erlenmeyer flasks using, separately, the yeasts Candida guilliermondii and Kluyveromyces marxianus. High cellulose (32.62%) and hemicellulose (23.60%) contents were found in this biomass, and the chemical hydrolysis yielded appreciable quantities of fermentable sugars, especially xylose. Both yeasts were able to metabolize xylose, but Candida guilliermondii produced only xylitol (9.35 g L-1 in 96 h), while K. marxianus produced ethanol as the main product (10.47 g L-1 in 24 h) and xylitol as byproduct (9.10 g L-1 xylitol in 96 h). Maximum activities of xylose reductase and xylitol dehydrogenase were verified after 24 h of fermentation with C. guilliermondii (0.23 and 0.53 U/mgprot, respectively) and with K. marxianus (0.08 e 0.08 U/mgprot, respectively). Apple pomace has shown potential as a raw material for the fermentation process, and the development of a biotechnological platform for the integrated use of both the hemicellulosic and cellulosic fraction could add value to this residue and the apple production chain.


Asunto(s)
Biotecnología/métodos , Etanol/química , Malus/metabolismo , Xilitol/química , Aldehído Reductasa/química , Biomasa , Reactores Biológicos , Candida , Celulosa/metabolismo , D-Xilulosa Reductasa/química , Fermentación , Glucosa/metabolismo , Hidrólisis , Kluyveromyces , Polímeros/química , Polisacáridos/química , Saccharomycetales , Factores de Tiempo , Xilosa/metabolismo
12.
Chem Biodivers ; 16(2): e1800372, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30673172

RESUMEN

This is the first time that composition, antimicrobial potential and antioxidant ability of essential oil from the leaves of Baccharis oreophila are reported. Essential oil was obtained by hydrodistillation and analyzed by GC/MS. Antimicrobial potential was evaluated by diffusion disk and broth microdilution methods. ABTS.+ , DPPH. and FRAP methods were employed for antioxidant activity evaluation. Essential oil yield was 0.47 %. Sixty-five compounds were identified, representing 88.53 % of the total essential oil, which showed to be rich in oxygenated (37.88 %) and hydrocarbons sesquiterpenes (34.84 %). The main constituents were khusimone (16.37 %) and spathulenol (16.12 %). Antimicrobial activity was verified against S. aureus (10.33±0.5 mm, MIC: 1250 µg mL-1 ) and C. albicans (8.66±0.5 mm, MIC: >2500 µg mL.1 ). Antioxidant ability was evidenced by FRAP (4.09 µmol FeSO4 E mL-1 ), ABTS.+ (1.45 µmol TE mL-1 ) and DPPH. (1.04 µmol TE mL-1 ) scavenging capacity. Results showed that this essential oil has interesting biological potential, encouraging further investigations especially in relation to action mechanisms of antimicrobial and antioxidant activity.


Asunto(s)
Antiinfecciosos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Baccharis/química , Aceites Volátiles/farmacología , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Candida albicans/efectos de los fármacos , Recuperación de Fluorescencia tras Fotoblanqueo , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Hojas de la Planta/química , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Staphylococcus aureus/efectos de los fármacos
13.
Int J Mol Sci ; 20(9)2019 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-31083511

RESUMEN

Exocellular (1→6)-ß-d-glucan (lasiodiplodan) produced by the fungus Lasiodiplodia theobromae MMPI was derivatized by carboxymethylation using different concentrations of a derivatizing agent. Lasiodiplodan was derivatized by carboxymethylation in an attempt to increase its solubility and enhance its biological activities. Carboxymethylglucans with degrees of substitution (DS) of 0.32, 0.47, 0.51, 0.58, and 0.68 were produced and characterized. FTIR analysis showed a band of strong intensity at 1600 cm-1 and an absorption band at 1421 cm-1, resulting from asymmetric and symmetrical stretching vibrations, respectively, of the carboxymethyl group COO- in the carboxymethylated samples. Thermal analysis showed that native lasiodiplodan (LN) and carboxymethylated derivatives (LC) exhibited thermal stability up to 200-210 °C. X-ray diffractometry demonstrated that both native and carboxymethylated lasiodiplodan presented predominantly an amorphous nature. Scanning electron microscopy revealed that carboxymethylation promoted morphological changes in the biopolymer and increased porosity, and alveolar structures were observed along the surface. The introduction of carboxymethyl groups in the macromolecule promoted increased solubility and potentiated the hydroxyl radical-scavenging activity, suggesting a correlation between degree of substitution and antioxidant activity.


Asunto(s)
Antioxidantes/farmacología , Ascomicetos/química , beta-Glucanos/metabolismo , beta-Glucanos/farmacología , Depuradores de Radicales Libres/química , Metilación , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termogravimetría , Difracción de Rayos X , beta-Glucanos/química
14.
Molecules ; 24(11)2019 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-31163607

RESUMEN

ß-Glucans are biomacromolecules well known, among other biological activities, for their immunomodulatory potential. Similarly, extracts of Baccharis dracunculifolia also possess biological properties and are used in folk medicine for the treatment of inflammation, ulcers, and hepatic diseases. Microparticles containing (1→6)-ß-d-glucan (lasiodiplodan) and B. dracunculifolia extract were produced and characterized. A 23 factorial design was employed to define the conditions of production of microparticles by atomization. Lasiodiplodan associated with maltodextrin and gum arabic was studied as a matrix material. Microparticles of 0.4 µm mean size and high phenolics content (3157.9 µg GAE/g) were obtained under the optimized conditions. The microparticle size ranged from 0.23 to 1.21 µm, and the mathematical model that best represented the release kinetics of the extract was the Korsmeyer-Peppas model. Diffusional exponent (n) values of 0.64 at pH 7.7 and 1.15 at pH 2.61 were found, indicating particles with a non-Fickian or anomalous transport system, and Super Case II transport, respectively. Thermal analysis indicated that the microparticles demonstrated high thermal stability. The X-ray diffraction analyses revealed an amorphous structure, and HPLC-DAD analysis showed microparticles rich in phenolic compounds: caffeic acid, p-coumaric acid, and catechin. The microparticles obtained comprise a new biomaterial with biological potential for applications in different fields.


Asunto(s)
Baccharis/química , Microesferas , Extractos Vegetales/química , beta-Glucanos/química , Antioxidantes/análisis , Goma Arábiga/química , Cinética , Modelos Teóricos , Tamaño de la Partícula , Fenoles/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Termogravimetría , Difracción de Rayos X
15.
Food Technol Biotechnol ; 57(4): 490-502, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32123511

RESUMEN

Sulfonated derivatives of lasiodiplodan (LAS-S) with different degrees of substitution (1.61, 1.42, 1.02 and 0.15) were obtained and characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermal and solubility analyses. Antimicrobial, antioxidant and cytotoxic potential were also assessed. The sulfonation was confirmed by FTIR analysis with specific bands at 1250 cm-1 (S=O, strong asymmetrical stretching vibration) and at 810 cm-1 (C-O-S, symmetrical vibration associated with the C-O-SO3 group) in the sulfonated samples. SEM demonstrated that sulfonation promoted morphological changes on the surface of the biopolymer with heterogeneous fibrillary structures appearing along the surface following chemical modification. LAS-S showed high thermal stability, with mass loss due to oxidation at temperatures close to 460 °C. Sulfonation increased the solubility of LAS, and in addition, increased the antimicrobial activity, especially against Candida albicans (fungicidal) and Salmonella enterica Typhimurium (bacteriostatic). Native lasiodiplodan (LAS-N) showed higher OH˙ removal capacity, while LAS-S had higher ferric ion reducing antioxidant power (FRAP) potential. LAS-N and LAS-S did not demonstrate lethal cytotoxicity against wild and mutant strains of Saccharomyces cerevisiae. Samples with higher degree of substitution (1.42 and 1.61) showed lower potential to induce oxidative stress.

16.
Glob Chang Biol ; 23(9): 3600-3609, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28107778

RESUMEN

While an understanding of evolutionary processes in shifting environments is vital in the context of rapid ecological change, one of the most potent selective forces, sexual selection, remains curiously unexplored. Variation in sexual selection across a species range, especially across a gradient of temperature regimes, has the potential to provide a window into the possible impacts of climate change on the evolution of mating patterns. Here, we investigated some of the links between temperature and indicators of sexual selection, using a cold-water pipefish as model. We found that populations differed with respect to body size, length of the breeding season, fecundity, and sexual dimorphism across a wide latitudinal gradient. We encountered two types of latitudinal patterns, either linear, when related to body size, or parabolic in shape when considering variables related to sexual selection intensity, such as sexual dimorphism and reproductive investment. Our results suggest that sexual selection intensity increases toward both edges of the distribution and that the large differences in temperature likely play a significant role. Shorter breeding seasons in the north and reduced periods for gamete production in the south certainly have the potential to alter mating systems, breeding synchrony, and mate monopolization rates. As latitude and water temperature are tightly coupled across the European coasts, the observed patterns in traits related to sexual selection can lead to predictions regarding how sexual selection should change in response to climate change. Based on data from extant populations, we can predict that as the worm pipefish moves northward, a wave of decreasing selection intensity will likely replace the strong sexual selection at the northern range margin. In contrast, the southern populations will be followed by heightened sexual selection, which may exacerbate the problem of local extinction at this retreating boundary.


Asunto(s)
Tamaño Corporal , Cambio Climático , Frío , Animales , Peces , Reproducción , Selección Genética , Caracteres Sexuales , Agua
17.
Pharm Biol ; 55(1): 1289-1294, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28274189

RESUMEN

CONTEXT: Lasiodiplodan, an exocellular (1→6)-ß-d-glucan of molecular weight >1.4 × 106 Da produced by MMPI strain of Lasiodiplodia theobromae (Pat.) Griffon & Maubl. (Brotyosphaeriaceae) is known to exhibit anti-proliferative activity on breast cancer cells (MCF-7), anticoagulant activity when sulfonylated, and reduction in transaminase activity when administered in rats. OBJECTIVE: The effect of intracerebroventricular (I.C.V) injection of lasiodiplodan on neurotoxicity and behavioural changes induced by d-penicillamine was investigated. MATERIALS AND METHODS: Twenty-four male Wistar rats were initially separated in groups of six and treated with 0.15 µmol/µL of NaCl (Groups Ct and d-Pen) and 0.01 µg/µL of lasiodiplodan (Groups Las and Las + d-Pen). After 15 min, they received 6 µmol/µL of NaCl (Groups Ct and Las) and 2 µmol/µL of d-penicillamine (Groups d-Pen and Las + d-Pen). The animal behavior was observed in an open-field test for 60 min. Twenty-four h later, the animals were sacrificed and histopathological analysis and Thiobarbituric acid reactive substances (TBARS) production measurements were performed. RESULTS: Lasiodiplodan prevented neurotoxicity induced by d-penicillamine significantly reducing the production of TBARS (308%; p < 0.05), and behavioural signs; convulsive and pre-convulsive. No histopathological alterations in the cerebral cortex were observed. DISCUSSION AND CONCLUSION: The reduction of TBARS production and convulsive episodes suggests that the protector effect provided by lasiodiplodan passes thought an antioxidant path, possibly interfering in a cascade of neurochemical events, triggering cell death and convulsive episodes. These results demonstrated that lasiodiplodan can be effective in treating neurotoxicity, and reducing damage triggered by convulsions in neuropathies related to GABAergic system.


Asunto(s)
Conducta Animal/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Fármacos Neuroprotectores/administración & dosificación , Penicilamina/toxicidad , Zearalenona/análogos & derivados , Animales , Conducta Animal/fisiología , Corteza Cerebral/metabolismo , Inyecciones Intraventriculares , Peroxidación de Lípido/fisiología , Masculino , Distribución Aleatoria , Ratas , Ratas Wistar , Zearalenona/administración & dosificación
18.
Pharm Biol ; 54(7): 1263-71, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26194070

RESUMEN

CONTEXT: Obesity is the main risk factor for type 2 diabetes mellitus. Secondary metabolites with biological activities and pharmacological potential have been identified in species of the Baccharis genus that are specifically distributed in the Americas. OBJECTIVE: This study evaluated the effects of methanol extracts from Baccharis dracunculifolia DC. Asteraceae on metabolic parameters, satiety, and growth in monosodium glutamate (MSG) induced-obesity model rats. MATERIALS AND METHODS: MSG was administered to 32 newborn rats (4 mg/g of body weight) once daily for 5 consecutive days. Four experimental groups (control, control + extract, MSG, and MSG + extract) were treated for 30 consecutive days with 400 mg/kg of B. dracunculifolia extract by gavage. Biochemical parameters, antioxidant activity, total extract phenolic content (methanolic, ethanolic, and acetone extractions), and pancreatic islets were evaluated. RESULTS: High levels of phenolic compounds were identified in B. dracunculifolia extracts (methanol: 46.2 ± 0.4 mg GAE/L; acetate: 70.5 ± 0.5 mg GAE/L; and ethanol: 30.3 ± 0.21 mg GAE/L); high antioxidant activity was detected in B. dracunculifolia ethanol and methanol extracts. The concentration of serum insulin increased 30% in obese animals treated with extract solutions (1.4-2.0 µU/mL, p < 0.05). Insulin secretion in pancreatic islets was 8.3 mM glucose (58%, p < 0.05) and 16.7 mM (99.5%, p < 0.05) in rats in the MSG + extract and MSG groups, respectively. DISCUSSION AND CONCLUSION: Treatment with B. dracunculifolia extracts protected pancreatic islets and prevented the irreversible cellular damage observed in animals in obesity and diabetes models.


Asunto(s)
Fármacos Antiobesidad/farmacología , Baccharis , Glucemia/efectos de los fármacos , Hipoglucemiantes/farmacología , Insulina/metabolismo , Islotes Pancreáticos/efectos de los fármacos , Metanol/química , Obesidad/tratamiento farmacológico , Extractos Vegetales/farmacología , Glutamato de Sodio , Solventes/química , Animales , Animales Recién Nacidos , Fármacos Antiobesidad/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Baccharis/química , Glucemia/metabolismo , Modelos Animales de Enfermedad , Hipoglucemiantes/aislamiento & purificación , Resistencia a la Insulina , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Masculino , Obesidad/inducido químicamente , Obesidad/metabolismo , Obesidad/fisiopatología , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales , Ratas Wistar , Factores de Tiempo
19.
Brain Sci ; 14(7)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-39061400

RESUMEN

Chemotherapy-induced peripheral neuropathy (CIPN) is a side effect of cancer treatment, often linked with pain complaints. Patients report mechanical and thermal hypersensitivity that may emerge during chemotherapy treatment and may persist after cancer remission. Whereas the latter situation disturbs the quality of life, life itself may be endangered by the appearance of CIPN during cancer treatment. The causes of CIPN have almost entirely been ascribed to the neurotoxicity of chemotherapeutic drugs in the peripheral nervous system. However, the central consequences of peripheral neuropathy are starting to be unraveled, namely in the supraspinal pain modulatory system. Based on our interests and experience in the field, we undertook a review of the brain-centered alterations that may underpin pain in CIPN. The changes in the descending pain modulation in CIPN models along with the functional and connectivity abnormalities in the brain of CIPN patients are analyzed. A translational analysis of preclinical findings about descending pain regulation during CIPN is reviewed considering the main neurochemical systems (serotoninergic and noradrenergic) targeted in CIPN management in patients, namely by antidepressants. In conclusion, this review highlights the importance of studying supraspinal areas involved in descending pain modulation to understand the pathophysiology of CIPN, which will probably allow a more personalized and effective CIPN treatment in the future.

20.
Nat Prod Res ; 38(10): 1799-1805, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37292020

RESUMEN

Phytochemical studies have shown extracts obtained from the aerial parts of Baccharis trimera (Less.) DC has antioxidant and antimicrobial activities and the potential to treat some diseases. This study investigated the phenolic compounds, antioxidant and antimicrobial activity, and phytochemical potential of B. trimera leaf extract obtained by decoction on ATCC standard bacterial strains and 23 swine clinical isolates. Water was used as an extraction solvent based on the principles of green chemistry and at a low cost. The decoction process resulted in an extract rich in phenolic compounds and a high capacity for scavenging DPPH and ABTS radicals. Phytochemical analysis of aqueous extracts was performed using HPLC-DAD, and high concentrations of chlorogenic, ferulic, caffeic, and cinnamic phenolic acids were found. Antimicrobial activity was observed against gram-negative bacteria. B. trimera aqueous extract may be a promising low-cost agent for prophylactic treatment against swine enteropathogens and contribute to reducing production costs.


Asunto(s)
Antiinfecciosos , Baccharis , Cinamatos , Animales , Porcinos , Antioxidantes/química , Extractos Vegetales/química , Baccharis/química , Fitoquímicos , Fenoles , Agua , Antiinfecciosos/análisis
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