20 research outputs found
Repetibilidad y reproducibilidad de las medidas de tejidos in vivo efectuadas con ultrasonidos en ovejas adultas y sus correlaciones con la condición corporal
La evaluación de la condición corporal permite conocer el estado de
reservas de los animales (Santucci et al., 1991; Delfa el al., 1995; Teixeira et al.,
1995), siendo el espesor de los tejidos en la región esternal el punto de elección en
caprinos tal como mostró Morand-Fehr et al. (1989). Este conocimiento permite
adecuar la alimentación de los animales, no obstante esta metodología es muy
susceptible a errores entre operadores (Evans, 1978). Así la substitución de esta
técnica por otras más objetivas presenta interés práctico. Las medidas de
ultrasonidos que permiten determinar las medidas de espesor de los tejidos, con
elevada repetible edad y reproducibilidad, podrán ser una alternativa interesante
Synthesis of novel methyl 7-[(hetero)arylamino]thieno[2,3-b] pyrazine-6-carboxylates and antitumor activity evaluation: effects in human tumor cells growth, cell cycle analysis, apoptosis and toxicity in non-tumor cells
Several novel methyl 7-[(hetero)arylamino]thieno[2,3-b]pyrazine-6-carboxylates were synthesized by Pd-catalyzed C–N Buchwald–Hartwig cross-coupling of either methyl 7-aminothieno[3,2-b]pyrazine-6-carboxylate with (hetero)arylhalides or 7-bromothieno[2,3-b]pyrazine-6-carboxylate with (hetero)arylamines in good-to-excellent yields (50% quantitative yield), using different reaction conditions, namely ligands and solvents, due to the different electronic character of the substrates. The antitumoral potential of these compounds was evaluated in four human tumor cell lines: gastric adenocarcinoma (AGS), colorectal adenocarcinoma (CaCo-2), breast carcinoma (MCF7), and non-small-cell lung carcinoma (NCI-H460) using the SRB assay, and it was possible to establish some structure–activity relationships. Furthermore, they did not show relevant toxicity against a non-tumor cell line culture from the African green monkey kidney (Vero). The most promising compounds (GI50 ≤ 11 µM), showed some selectivity either against AGS or CaCo-2 cell lines without toxicity at their GI50 values. The effects of the methoxylated compounds 2b (2-OMeC6H4), 2f and 2g (3,4- or 3,5-diOMeC6H3, respectively) on the cell cycle profile and induction of apoptosis were further studied in the AGS cell line. Nevertheless, even for the most active (GI50 = 7.8 µM) and selective compound (2g) against this cell line, it was observed that a huge number of dead cells gave rise to an atypical distribution on the cell cycle profile and that these cells were not apoptotic, which points to a different mechanism of action for the AGS cell growth inhibition.This research was funded by Fundação para a Ciência e Tecnologia (FCT)—Portugal, which
financially supports CQUM (UID/QUI/686/2019), and also financed by the European Regional
Develop- ment Fund (ERDF), COMPETE2020 and Portugal2020, and the PTNMR network also
supported by Portugal2020. J.M.R. PhD grant (SFRH/BD/115844/2016) was financed by FCT, ESF
(European Social Fund—North Portugal Regional Operational Program) and HCOP (Human Capital
Operational Program). The authors are grateful to FCT, Portugal, for financial support through
national funds FCT/MCTES to the CIMO (UIDB/00690/2020). L.B. and R.C.C. thank the national
funding by FCT, Portugal, through the institutional scientific employment program-contract for
their contracts
Potential therapeutic applications of infusions and hydroalcoholic extracts of Romanian glutinous sage (Salvia glutinosa L.)
Ethnopharmacological relevance: Salvia glutinosa, also known as the glutinous
sage, has been used in Romanian folk medicine in the treatment of
inflammation, injuries, and mild infections. However, there is no direct
scientific evidence to demonstrate these activities. Aim of the Study: The present research was based on evaluating antioxidant,
antiproliferative, and α-glucosidase inhibitory activity of S. glutinosa extracts, as
well as the in vivo anti-inflammatory activity.
Materials and Methods: Infusions and 70% (v:v) ethanol solution extracts of S.
glutinosa stems and leaves, collected from two different locations in Romania,
were prepared. Ten phenolic compounds were identified and quantified using
the LC-DAD-ESI/MSn method, and total phenolic and flavonoid content, as well
as in vitro antioxidant (DPPH, ABTS, and FRAP assays), antiproliferative, antiinflammatory
and alpha-glucosidase inhibitory activities were determined. A rat
model of induced inflammation with turpentine oil was used for the
examination of in vivo effects of the extracts, using diclofenac as an antiinflammatory
control. Results: The highest inhibitory α-glucosidase activity was determined to be
IC50 = 0.546 mg/ml for the hydroalcoholic extract made with plant material
collected on the road to Sighișoara. The highest cytotoxic activity against
HepG2 cell line was determined to be GI50 = 131.68 ± 5.03 μg/ml, for the
hydroalcoholic extract made with plant material from Sighișoara. In vivo
administration of extract (200 mg lyophilized powder/ml) showed a
significant reduction of NO production.Conclusion: Our findings indicate that S. glutinosa extracts exhibit antioxidant, α-glucosidase inhibitory activity, as well as a modest cytotoxic effect on HepG2 cell line. By in vivo administration, the extracts show antiinflammatory
and antioxidant activity, which correlates with the traditional
use of the species. The environmental conditions seemed to induce
important changes in the chemical composition and the bioactivity of the
herbal preparations derived from S. glutinosa.This work was supported by a grant of the Romanian
Ministry of Education and Research, CNCS–UEFISCDI,
project number PN-III-P2-2.1-PED-2019–5360.info:eu-repo/semantics/publishedVersio
Chemical composition, diuretic, and antityrosinase activity of traditionally used romanian cerasorum stipites
Cherry stems (CS) represent a by-product intensively used in Eastern European countries as a traditional remedy for urinary tract disorders. Ethnopharmacological evidences sustain the use of CS as aqueous preparations (infusion and decoction), but few data were previously reported about phytochemical profile and pharmacological potential of CS hydroalcoholic extracts. In this regard, we aimed to evaluate the phenolic profile, in vitro antioxidant and tyrosinase inhibitory potential, and in vivo diuretic activity of 70% hydroethanolic cherry stems extract and cherry stems decoction (CSD). LC-DAD-ESI/MSn analysis revealed the presence of flavonoid-type compounds as main constituents for both preparations, especially flavanones (naringenin glycosides). Antioxidant activity evaluated through DPPH, ABTS, and FRAP methods was superior for cherry stems extract, probably due to the presence of phenolic-derived compounds in higher amounts than CSD. On the other hand, tyrosinase inhibitory potential and diuretic effect exerted by CSD were stronger, highlighting that other types of hydrophilic secondary metabolites are responsible for this bioactivity. Overall, our findings indicate that CS preparations could be used as promising mild diuretic agents and encourage further investigations regarding the correlation between their chemical composition and bioactive potential.This work was supported by a Grant of the Romanian Ministry
of Education and Research, CCCDI—UEFISCDI, project
number PN-III-P2-2.1-PED-2019-5360, within PNCDI III.”
The authors MID, LB, and ICFRF are grateful to the
Foundation for Science and Technology (FCT, Portugal) for
financial support through national funds FCT/MCTES to
CIMO (UIDB/00690/2020) and FCT/MCTES (PIDDAC);
national funding by F.C.T. and P.I., through the
institutional scientific employment program-contract for
MID and LB contracts. To FEDER-Interreg Es-paña-
Portugal programme for financial support through the
project TRANSCoLAB 0612_TRANS_CO_LAB_2_P.info:eu-repo/semantics/publishedVersio
EMG signal processing for the study of localized muscle fatigue—pilot study to explore the applicability of a novel method
This pilot study aimed to explore a method for characterization of the electromyogram
frequency spectrum during a sustained exertion task, performed by the upper limb. Methods: Nine
participants underwent an isometric localized muscle fatigue protocol on an isokinetic
dynamometer until exhaustion, while monitored with surface electromyography (sEMG) of the
shoulder’s external rotators. Firstly, three methods of signal energy analysis based on primer
frequency contributors were compared to the energy of the entire spectrum. Secondly, the chosen
method of analysis was used to characterize the signal energy at beginning (T1), in the middle (T2)
and at the end (T3) of the fatigue protocol and compared to the torque output and the shift in the
median frequencies during the trial. Results: There were statistically significant differences between
T1 and T3 for signal energy (p < 0.007) and for central frequency of the interval (p = 0.003). Moreover,
the isometric peak torque was also different between T1 and T3 (p < 0.001). Overall, there were no
differences between the signal energy enclosed in the 40 primer frequency contributors and the
analysis of the full spectrum energy; consequently, it was the method of choice. The reported fatigue
and the decrease in the produced muscle torque was consistent with fatigue-induced alterations in
the electromyogram frequency spectrum. In conclusion, the developed protocol has potential to be
considered as an easy-to-use method for EMG-based analysis of isometric muscle exertion until
fatigue. Thus, the novelty of the proposed method is to explore, in muscle fatigue, the use of only
the main contributors in the frequency domain of the EMG spectrum, avoiding surplus information,
that may not represent muscle functioning. However, further studies are needed to investigate the
stability of the present findings in a more comprehensive sample.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal)
for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020
and UIDP/05757/2020) and SusTEC (LA/P/0007/2021).info:eu-repo/semantics/publishedVersio
Optimized ultrasound-assisted extraction of phenolic compounds from Thymus comosus Heuff. ex Griseb. et Schenk (wild thyme) and their bioactive potential
An optimized ultrasound-assisted extractive method was developed to obtain a polyphenol-enriched extract from
the aerial parts of Thymus comosus Heuff. ex Griseb. et Schenk. Optimization process was conducted based on
Design of Experiment (DoE) principles, determining the influence of three independent variables (time, ultrasound
amplitude, ethanol concentration) on the total phenolic content of the extract (dependent variable).
Additionally, the phenolic composition of the extract was characterized through UHPLC-HRMS, revealing beside
the most abundant flavonoid-type compounds the presence of salvianolic acids C, D and L in high amounts.
Phytochemical profile of the extract was correlated with its antioxidant activity (tested through five complementary
assays) and enzyme-inhibitory potential, showing important antiglucosidase and anticholinesterase
effects. Overall, it was concluded that the developed method is suitable for obtaining a good recovery of both
phenolic and non-phenolic compounds from Thymus comosus aerial parts, and their presence in the optimized
extract is responsible for its pharmacological potential.This work was supported by a grant of the Romanian Ministry of
Education and Research, CNCS – UEFISCDI, project number PN-III-P1-
1.1-PD-2019-1245, within PNCDI III”. The authors are grateful to the
Foundation for Science and Technology (FCT, Portugal) for financial
support through national funds FCT/MCTES to CIMO (UIDB/00690/2020), and for the contracts of J. Pinela (CEECIND/01011/2018) and L.
Barros (institutional scientific employment program-contract).info:eu-repo/semantics/publishedVersio
Development of an optimized drying process for the recovery of bioactive compounds from the Autumn Fruits of Berberis vulgaris L. and Crataegus monogyna Jacq
Hot air drying has proven to be an efficient method to preserve specific edible plant materials
with medicinal properties. This is a process involving chemical, physical, and biological
changes in plant matrices. Understanding these processes will lead to an improvement in the yields
of bioactive compounds. This study aims to optimize the drying process of two species’ fruits used
in folk medicine, Berberis vulgaris and Crataegus monogyna. The optimized extracts’ antioxidant capacity
was assessed using various assays, with the barberry extract showing very good activity
(50.85, 30.98, and 302.45 mg TE/g dw for DPPH, TEAC, and FRAP assays, respectively). Both species
exerted good fungal α-glucosidase inhibitory activity (IC50 = 0.34 and 0.56 mg/mL, respectively) but
no activity on mammalian α-glucosidase. Additionally, this study identified and quantified the
main bioactive compounds. The results presented herein are a breakthrough in industrializing this
drying process. Additional studies are necessary to mechanistically understand the drying process
involved in these plant materials.This work was supported by a grant of the Romanian Ministry of Education and Research,
CNCS–UEFISCDI, project number PN-III-P2-2.1-PED-2019-5360.The authors are grateful to the Foundation for Science and Technology (FCT; Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020), the national funding for F.C.T. and P.I. and through the institutional scientific employment program contract for M.I.D., and L.B. The authors are grateful to FEDER—Interreg España—Portugal programme
for financial support through the project TRANSCoLAB 0612_TRANS_CO_LAB_2_P.info:eu-repo/semantics/publishedVersio
Valorization of Corn Silk as an Agricultural By-Product through the Optimization of Ultrasound-Assisted Extraction
Corn silk, derived from the stigmas of corn (Zea mays, Poaceae) flowers, possesses valuable bioactive compounds that can be harnessed for therapeutical, nutritional, and industrial purposes. This research aimed to optimize the extraction of bioactive compounds from corn silk, specifically flavonoids and total antioxidant capacity, by comparing it with classical extraction (infusion and maceration). The study identified significant factors influencing total flavonoid content (TFC) and antioxidant activity (assessed through an ABTS assay), including ethanol concentration, ultrasonic amplitude, and their quadratic interactions. This optimized combination of independent variables (37.89% ethanolic concentration, 48.58% ultrasound amplitude, and an extraction time of 38.72 min) yielded a balanced extraction, maximizing both TFC and antioxidant activity. Further analyses revealed significant total phenolic content, total flavonoid content (50.69 ± 0.36 mg GAE, 23.54 ± 0.01 mg QE, and 78.33 ± 0.94 mg TE/g extract, respectively), and potent in vitro antioxidant activity, affirming the efficacy of the optimized extraction. The study also explored the inhibitory effects on α-glucosidase (IC50 = 411.67 ± 25.39 µg/mL), acetylcholinesterase (IC50 = 1166.4 ± 399.38 µg/mL), and pancreatic lipase (IC50 = 1519.67 ± 209.04 µg/mL), showcasing potential antidiabetic and neuroprotective properties. While tyrosinase inhibition activity was not observed, the research emphasizes the nutraceutical potential of corn silk, offering valuable insights for its utilization and further exploration in the pharmaceutical and functional food industries
Contextos da adesão e do abandono do tratamento por portadores de HIV em países de baixa renda
Não podemos esquecer que o diagnóstico da seropositividade causa um grande
impacto no indivíduo, despoletando sentimentos e emoções negativas. Assim sendo, é
preciso que ele conheça a doença e o tratamento, para perceber que a adaptação a um
novo estilo de vida é necessária, mas não é limitadora da vida (Camargo, 2013). Dessa
forma poderá encarar a cronicidade do VIH/SIDA e o processo de adesão a um regime
de tratamento completo e prolongado, evitando falhas que aumentam o risco de incompleta
supressão viral e ainda de desenvolvimento de cepas virais resistentes aos medicamentos
disponíveis (Feitosa, Lima, Caetano, Andrade, & Beserra, 2008). A adesão
à terapia antirretroviral (TARV) está fortemente associada à supressão viral máxima e
duradoura, reduzidas taxas de resistência e aumento da sobrevida e qualidade de vida
dos pacientes. Constitui um desafio para o paciente e equipa multidisciplinar, pois trata-
se de uma doença crónica que exige acompanhamento ambulatorial e laboratorial
frequentes, além de uma rigorosa toma de medicação prescrita (Menezes et al., 2019).
A adesão ao tratamento também reflete a forma como o paciente percepciona a
relação da necessidade do uso de medicamentos com a doença.info:eu-repo/semantics/publishedVersio
Biological Activity of Bark Extracts from Northern Red Oak (Quercus rubra L.): An Antioxidant, Antimicrobial and Enzymatic Inhibitory Evaluation
The northern red oak (Quercus rubra L.) is an ornamental oak species native to eastern America, being an invasive species in Europe, with increasing coverage. The aim of this work was to evaluate the biological potential of red oak bark extracts. Aqueous and ethanolic preparations were obtained by two extraction methods: ultrasonic-assisted extraction (UAE) and microwave assisted extraction (MAE). The total phenolic and tannin contents were measured using spectrophotometric methods. The antioxidant activity was evaluated by two complementary methods (DPPH and ABTS). Antimicrobial potential was tested against five bacteria and three Candida species, and the effect on biofilm formation and synergism with gentamicin was also evaluated. Finally, enzyme inhibitory properties were assessed for α-glucosidase, tyrosinase, and acetylcholinesterase. The results indicated a higher phenolic content for the extracts obtained through MAE, while UAE bark extracts were rich in tannins. All the extracts exhibited antioxidant, anti-glucosidase, and anti-tyrosinase activity, while the antibacterial potential was mostly observed for the MAE extracts, especially against S. aureus, C. parapsilopsis, and C. krusei; inhibition of biofilm formation was observed only for MRSA. These findings show that the red oak bark might be an important source of bioactive compounds with antioxidant and antimicrobial properties