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1.
Plants (Basel) ; 12(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36771747

RESUMEN

Weeds are major threats to the integrity of agricultural and natural environments due to their invasive and competing potential. Bioherbicides are substances based on natural compounds that are biodegradable and often have low residual effects. Plant species able to produce and release phytotoxic compounds may represent effective bioherbicide sources. Leaves of Quillaja lancifolia D.Don (formerly Q. brasiliensis (A.St.-Hil. & Tul.) Mart.) produce water-soluble specialized metabolites of the saponin class that could be evaluated for phytotoxic activity and potential as natural herbicides. This study was conducted to examine the impacts of Q. lancifolia total saponins aqueous extract (AE) at 4 and 10% (w/v) and of two combined reverse-phase chromatography purified saponin fractions (QB) at 1 and 2% (w/v) on morpho-physiological parameters of Lactuca sativa (lettuce) and Echinochloa crus-galli (barnyardgrass) in pre- and post-emergence bioassays. QB was only tested in pre-emergence assays. In pre-emergence bioassays, the germination rate and germination kinetics were determined. Post-emergence evaluations included effects on seedling morphology, root and shoot length, dry mass, and chlorophyll content. Osmotic potential and pH analyses ruled out roles for these factors in the observed responses. AE had a high inhibitory impact on the germination of both lettuce and barnyardgrass. QB at 1% and 2% (w/v) significantly decreased the growth of lettuce seedlings germinated in its presence by more than 10-fold. Phytotoxic effects on the post-emergence growth of lettuce, especially at the highest concentration tested of AE (10% w/v), was also observed. The presence of quillaic acid-based triterpene saponins in AE and QB was confirmed using different analytical methods. Therefore, both saponin-enriched fraction and aqueous extracts of Q. lancifolia inhibited tested plant growth and development. The water solubility of saponins and the availability of a sustainable source of these molecules from the leaves of cultivated young Q. lancifolia plants make them attractive candidates for use as bioherbicides.

2.
J Comp Pathol ; 201: 16-22, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36646035

RESUMEN

Entomopathogenic fungi, widely available biological agents used to control agricultural pests, are sporadically reported to cause focal or disseminated infection in reptiles and mammals, including humans. This study summarizes the clinical presentation, histopathological and molecular findings by panfungal polymerase chain reaction and sequencing of four cases of hypocrealean fungal infections in captive common green iguanas (Iguana, iguana). One case of granulomatous pneumonia, hepatitis and serositis was related to Metarhizium flavoviride complex infection. Two disseminated fungal infection cases, with scarce inflammatory cell infiltration, were caused by Beauveria bassiana while there was one case of multifocal granulomatous and necrotizing pneumonia by Purpureocillium spp. To the best of our knowledge, this is the first report of fatal mycosis infection due to entomopathogenic fungi in captive common green iguanas.


Asunto(s)
Beauveria , Hypocreales , Iguanas , Micosis , Animales , Humanos , Brasil , Micosis/microbiología , Micosis/veterinaria , Mamíferos
3.
Neoplasia ; 36: 100872, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36621024

RESUMEN

PURPOSE: Glioblastoma(GBM) is a lethal disease characterized by inevitable recurrence. Here we investigate the molecular pathways mediating resistance, with the goal of identifying novel therapeutic opportunities. EXPERIMENTAL DESIGN: We developed a longitudinal in vivo recurrence model utilizing patient-derived explants to produce paired specimens(pre- and post-recurrence) following temozolomide(TMZ) and radiation(IR). These specimens were evaluated for treatment response and to identify gene expression pathways driving treatment resistance. Findings were clinically validated using spatial transcriptomics of human GBMs. RESULTS: These studies reveal in replicate cohorts, a gene expression profile characterized by upregulation of mesenchymal and stem-like genes at recurrence. Analyses of clinical databases revealed significant association of this transcriptional profile with worse overall survival and upregulation at recurrence. Notably, gene expression analyses identified upregulation of TGFß signaling, and more than one-hundred-fold increase in THY1 levels at recurrence. Furthermore, THY1-positive cells represented <10% of cells in treatment-naïve tumors, compared to 75-96% in recurrent tumors. We then isolated THY1-positive cells from treatment-naïve patient samples and determined that they were inherently resistant to chemoradiation in orthotopic models. Additionally, using image-guided biopsies from treatment-naïve human GBM, we conducted spatial transcriptomic analyses. This revealed rare THY1+ regions characterized by mesenchymal/stem-like gene expression, analogous to our recurrent mouse model, which co-localized with macrophages within the perivascular niche. We then inhibited TGFBRI activity in vivo which decreased mesenchymal/stem-like protein levels, including THY1, and restored sensitivity to TMZ/IR in recurrent tumors. CONCLUSIONS: These findings reveal that GBM recurrence may result from tumor repopulation by pre-existing, therapy-resistant, THY1-positive, mesenchymal cells within the perivascular niche.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Animales , Ratones , Humanos , Glioblastoma/metabolismo , Línea Celular Tumoral , Neoplasias Encefálicas/patología , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/tratamiento farmacológico , Temozolomida/farmacología , Resistencia a Antineoplásicos/genética , Antineoplásicos Alquilantes/farmacología
4.
Molecules ; 27(17)2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-36080159

RESUMEN

The aim of this study was to investigate the cytotoxic activity of the Coriandrum sativum (C. sativum) ethanolic extract (CSEE) in neuroblastoma cells, chemically characterize the compounds present in the CSEE, and predict the molecular interactions and properties of ADME. Thus, after obtaining the CSEE and performing its chemical characterization through dereplication methods using UPLC/DAD-ESI/HRMS/MS, PM6 methods and the SwissADME drug design platform were used in order to predict molecular interactions and ADME properties. The CSEE was tested for 24 h in neuroblastoma cells to the establishment of the IC50 dose. Then, the cell death was evaluated, using annexin-PI, as well as the activity of the effector caspase 3, and the protein and mRNA levels of Bax and Bcl-2 were analyzed by ELISA and RT-PCR, respectively. By UHPLC/DAD/HRMS-MS/MS analysis, the CSEE showed a high content of isocoumarins-dihydrocoriandrin, coriandrin, and coriandrones A and B, as well as nitrogenated compounds (adenine, adenosine, and tryptophan). Flavonoids (apigenin, hyperoside, and rutin), phospholipids (PAF C-16 and LysoPC (16:0)), and acylglicerol were also identified in lower amount as important compounds with antioxidant activity. The in silico approach results showed that the compounds 1 to 6, which are found mostly in the C. sativum extract, obey the "Five Rules" of Lipinski, suggesting a good pharmacokinetic activity of these compounds when administered orally. The IC50 dose of CSEE (20 µg/mL) inhibited cell proliferation and promoted cell death by the accumulation of cleaved caspase-3 and the externalization of phosphatidylserine. Furthermore, CSEE decreased Bcl-2 and increased Bax, both protein and mRNA levels, suggesting an apoptotic mechanism. CSEE presents cytotoxic effects, promoting cell death. In addition to the promising results predicted through the in silico approach for all compounds, the compound 6 showed the best results in relation to stability due to its GAP value.


Asunto(s)
Coriandrum , Neuroblastoma , Línea Celular Tumoral , Coriandrum/química , Humanos , Neuroblastoma/tratamiento farmacológico , Extractos Vegetales/química , Proteínas Proto-Oncogénicas c-bcl-2 , ARN Mensajero , Espectrometría de Masas en Tándem , Proteína X Asociada a bcl-2/genética
5.
Aging Clin Exp Res ; 34(3): 619-624, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34460081

RESUMEN

BACKGROUND: Hospitalization episodes in older people are considered critical events because they act in a complex interaction among immobilization effects. AIM: The purpose of this study was to evaluate the effects of hospitalization on older adults' handgrip strength (HGS) and to identify factors related to its performance on the test. METHODS: A cohort study was conducted in a hospital in Natal, Brazil, and enrolled all patients aged 60 years and older between January 2014, and April 2015. Cognitive (Leganés Cognitive Test) and functional status (Katz Index, Lawton Scale and Functional limitation Nagi), physical performance (HGS and gait speed) and depressive symptom assessment (GDS-15) were evaluated at admission and discharge time, as well as information about health and functional status prior to hospitalization. Linear Mixed Models were used to create a predictive model for handgrip strength. RESULTS: A total of 1168 hospitalized older adults were evaluated. A significant decrease in HGS means was observed between admission and discharge time for men (28.12 ± 10.35 and 20.22 ± 14.08 Kgf, p < 0.01) and for women (19.18 ± 7.87 and 14.88 ± 9.79 Kgf, p < 0.01). Undergoing surgery and basal values of the Katz Index were associated with worse HGS performance at discharge. CONCLUSION: A significant decline in handgrip strength during the hospitalization period was observed, which was more pronounced in men. Performing surgery during hospitalization was an important factor for HGS decline in men and women. This study reinforces the importance of early mobilization and muscle strength loss prevention protocols in hospitalized older patients.


Asunto(s)
Fuerza de la Mano , Hospitalización , Anciano , Estudios de Cohortes , Femenino , Fuerza de la Mano/fisiología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Alta del Paciente
6.
PLoS One ; 16(6): e0253418, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34138935

RESUMEN

BACKGROUND: Oropharyngeal cancer is an important public health problem. The aim of our study was to correlatep16 immunohistochemistry in oropharynx squamous cell carcinomas(OPSCC) with clinical and epidemiological features. MATERIAL AND METHODS: We conducted across-sectional study on patients with OPSCC treated at a single institution from 2014 to 2019. Epidemiological and clinical-pathological data were collected from medical records and a questionnaire was applied to determine alcohol consumption, smoking, and sexual behavior. The HPV status was determined by p16 immunohistochemistry. RESULTS: A total of 252 patients participated in the study, of these 221 (87.7%) were male. There were 81 (32.14%) p16 positive cases and 171 (67.85%) p16 negative cases. The p16positive group was significantly associated with younger patients (50-59 years), higher education level, lower clinical stage and patients who never drank or smoked. Through univariate logistic regression, we observed that female sex (OR, 3.47; 95% CI, 1.60-7.51) and higher education level (OR, 9.39; 95% CI, 2, 81-31,38) were significantly more likely to be p16 positive. Early clinical stage (AJCC8ed) was more associated with p16 positivity both in univariate (OR, 0.14; 95% CI, 0.07-0.26, p<0.001) and multivariate analysis (OR, 0.18; 95% CI, 0.06-0.49, p = 0.001). CONCLUSION: This study showed that drinkers and current smokers were less likely to be p16+. Female sex, higher education level and younger age at diagnosis were associated with a higher probability of being p16+. Additionally, there was a higher proportion of patients with early clinical stage (I or II) in the p16 positive group when compared to the p16 negative group.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Neoplasias Orofaríngeas/metabolismo , Orofaringe/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Consumo de Bebidas Alcohólicas , Estudios Transversales , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Orofaríngeas/epidemiología , Neoplasias Orofaríngeas/patología , Orofaringe/patología , Factores de Riesgo , Factores Sexuales , Conducta Sexual , Fumar , Carcinoma de Células Escamosas de Cabeza y Cuello/epidemiología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Adulto Joven
7.
Bioorg Chem ; 83: 205-213, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30380449

RESUMEN

Twenty-one isovanillin derivatives were prepared in order to evaluate their cytotoxic properties against the cancer cell lines B16F10-Nex2, HL-60, MCF-7, A2058 and HeLa. Among them, seven derivatives exhibited cytotoxic activity. We observed that for obtaining smaller IC50 values and for increasing the index of selectivity, two structural features are very important when compared with isovanillin (1); a hydroxymethyl group at C-1 and the replacement of the hydroxyl group at C-3 by different alkyl groups. As the lipophilicity of the compounds was changed, we decided to investigate the interaction of the cytotoxic isovallinin derivatives on cell membrane models through Langmuir monolayers by employing the lipids DPPC (1,2-diplamitoyl-sn-glycero-3-phosphocoline) and DPPS (1,2-diplamitoyl-sn-glycero-3-phosphoserine). The structural changes on the scaffold of the compounds modulated the interaction with the phospholipids at the air-water interface. These results were very important to understand the biophysical aspects related to the interaction of the cytotoxic compounds with the cancer cell membranes.


Asunto(s)
Antineoplásicos/farmacología , Benzaldehídos/farmacología , Membranas Artificiales , 1,2-Dipalmitoilfosfatidilcolina/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Benzaldehídos/síntesis química , Benzaldehídos/química , Línea Celular Tumoral , Humanos , Ratones , Fosfatidilserinas/química , Propiedades de Superficie
8.
Onco Targets Ther ; 6: 713-23, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23836983

RESUMEN

Osteosarcoma (OS) is the eighth most common form of childhood and adolescence cancer. Approximately 10%-20% of patients present metastatic disease at diagnosis and the 5-year overall survival remains around 70% for nonmetastatic patients and around 30% for metastatic patients. Metastatic disease at diagnosis and the necrosis grade induced by preoperative treatment are the only well-established prognostic factors for osteosarcoma. The DNA aberrant methylation is a frequent epigenetic alteration in humans and has been described as a molecular marker in different tumor types. This study evaluated the DNA aberrant methylation status of 18 genes in 34 OS samples without previous chemotherapy treatment and in four normal bone specimens and compared the methylation profile with clinicopathological characteristics of the patients. We were able to define a three-gene panel (AIM1, p14ARF, and ESR1) in which methylation was correlated with OS cases. The hypermethylation of p14ARF showed a significant association with the absence of metastases at diagnoses, while ESR1 hypermethylation was marginally associated with worse overall survival. This study demonstrated that aberrant promoter methylation is a common event in OS and provides evidence that p14ARF and ESR1 hypermethylation could be useful as a prognostic indicator for this disease.

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