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1.
An Acad Bras Cienc ; 95(2): e20220159, 2023.
Article de Anglais | MEDLINE | ID: mdl-37341272

RÉSUMÉ

The hydrological basins can be considered sources of relevant information about the evolution of the Earth's crust since the relief forms that define the hydrographic channels are the resultant of the interaction between tectonics, pedogenics, intemperics and thermals processes. The geothermal field of Muriaé watershed was evaluated using eight (8) thermal logs and twenty-two (22) geochemical logs. The structural lineaments evidenced on the surface were interpreted jointly with the identification of sixty-five (65) magnetic lineaments from airborne magnetic data interpretation. The depths of these structures were range from the surface up to 4.5 km. The interpreted data allowed identification of regional tectonics features in the NE-SW direction, where the identified magnetic lineaments show a spatial correlation with accentuated topographic structures. The differences in the depths of the magnetic bodies found in conjunction with the heat flow distribution, evidence two distinct thermostructural zones: A1 (east part) presenting heat flow values within the average (approximately 60$\frac{mW.


Sujet(s)
Oestrus , Température élevée , Animaux , Brésil
3.
Nat Prod Res ; 36(4): 1043-1047, 2022 Feb.
Article de Anglais | MEDLINE | ID: mdl-33161760

RÉSUMÉ

This paper aims to investigate, for the first time, physicochemical characteristics and antioxidant capacity of Psidium myrtoides ripe and unripe fruit. In addition, essential oil was extracted from fresh leaves (PM-EO) collected in dry and rainy seasons to investigate the influence of seasonality and, after that, to evaluate its antifungal activity on mycelial growth of Colletotrichum gloeosporioides. Both GC-FID and GC-MS analyses revealed that major components determined in PM-EO were ß-caryophyllene (20.0% and 32.9%) and limonene (10.4% and 19.8%) in rainy and dry seasons, respectively. High antioxidant capacity was displayed by unripe fruit (IC50 = 3.57 mg/mL) and ripe ones (IC50 = 3.68 mg/mL). Both showed high total phenolic and tannin contents. In sum, PM-EO showed satisfactory antifungal activity, since its inhibitory action on mycelial growth of C. gloeosporioides was above 70% in the dry season, while it exhibited weak activity in the rainy season.


Sujet(s)
Huile essentielle , Psidium , Antifongiques/composition chimique , Fruit/composition chimique , Huile essentielle/composition chimique , Feuilles de plante/composition chimique , Psidium/composition chimique , Saisons
4.
Nat Prod Res ; 34(16): 2378-2383, 2020 Aug.
Article de Anglais | MEDLINE | ID: mdl-30499330

RÉSUMÉ

In Brazilian folk medicine, Protium heptaphyllum is used to treat inflammatory conditions and to hasten wound repair. This paper aims to investigate the chemical composition and the in vitro antibacterial effects of the essential oils (EOs) obtained from P. heptaphyllum leaves and ripe and unripe fruits against a representative panel of oral pathogens. The GC-FID and GC-MS analysis revealed that the major components determined in P. heptaphyllum essential oils were myrcene (59.0%), ß-elemene (17.2%), limonene (12.9%), spathulenol (12.6%), α-cubebene (11.6%), germacrene D (10.6%), trans-nerolidol (9.8%), and α-cadinol (8.8%). The essential oils of the ripe and unripe fruits showed the strongest antibacterial activity against the anaerobic bacteria Prevotella nigrescens (MIC = 50 µg/mL). The leaf essential oil displayed very promising activity against Streptococcus mutans (MIC = 50 µg/mL) and Streptococcus mitis (MIC = 62.5 µg/mL). The antibacterial activity of EOs against oral pathogens is also described for the first time. [Formula: see text].


Sujet(s)
Antibactériens/isolement et purification , Burseraceae/composition chimique , Huile essentielle/composition chimique , Monoterpènes acycliques/analyse , Alcènes/analyse , Antibactériens/composition chimique , Antibactériens/pharmacologie , Tests de sensibilité microbienne , Sesquiterpènes/analyse , Sesquiterpènes de type germacrane/analyse , Streptococcus mutans/effets des médicaments et des substances chimiques , Terpènes/analyse
7.
Nat Prod Res ; 33(17): 2566-2570, 2019 Sep.
Article de Anglais | MEDLINE | ID: mdl-29611435

RÉSUMÉ

In this study, the chemical composition and antibacterial and antiproliferative potential of the essential oil obtained from fresh leaves of Psidium myrtoides (PM-EO) against oral pathogens and human tumour cell lines were investigated for the first time. GC-FID and GC-MS analyses showed that trans-ß-caryophyllene (30.9%), α-humulene (15.9%), α-copaene (7.8%), caryophyllene oxide (7.3%) and α-bisabolol (5.3%) are the major constituents of PM-EO. The antibacterial activity of PM-EO against a panel of oral pathogens was investigated in terms of their minimal inhibitory concentrations (MIC) using the broth microdilution method. PM-EO displayed moderate activity against Streptococcus mitis (MIC = 100 µg/mL), S. sanguinis (MIC = 100 µg/mL), S. sobrinus (MIC = 250 µg/mL), and S. salivarius (MIC = 250 µg/mL), and strong activity against S. mutans (MIC = 62.5 µg/mL). The antiproliferative activity in normal (GM07492A, lung fibroblasts) and tumour cell lines (MCF-7, HeLa, and M059 J) was performed using the XTT assay. PM-EO showed 50% inhibition of normal cell growth at 359.8 ± 6.3 µg/mL. Antiproliferative activity was observed against human tumour cell lines, with IC50 values significantly lower than that obtained for the normal cell line, demonstrating IC50 values for MCF-7 cells (254.5 ± 1.6 µg/mL), HeLa cells (324.2 ± 41.4 µg/mL) and M059 J cells (289.3 ± 10.9 µg/mL). Therefore, the cytotoxicity of PM-EO had little influence on the antibacterial effect, since it showed antibacterial activity at lower concentrations. Our results suggest that PM-EO is a promising source of new antibacterial and antitumour agents.


Sujet(s)
Antibactériens/pharmacologie , Antinéoplasiques/pharmacologie , Huile essentielle/composition chimique , Psidium/composition chimique , Lignée cellulaire tumorale , Chromatographie gazeuse-spectrométrie de masse , Humains , Tests de sensibilité microbienne , Sesquiterpènes monocycliques , Myrtaceae/composition chimique , Extraits de plantes/pharmacologie , Feuilles de plante/composition chimique , Sesquiterpènes polycycliques , Sesquiterpènes/analyse
8.
Ir Med J ; 110(7): 618, 2017 Aug 12.
Article de Anglais | MEDLINE | ID: mdl-29169000

RÉSUMÉ

Hidradenitis Suppurativa (HS) is characterized by chronic recurrent abscesses, nodules and draining sinus tracts with scar formation. Cutaneous Crohn's Disease (CD) may also present similarly. We wished to identify and describe an Irish cohort with combined HS and CD, with a view to a better recognition of clinical manifestations and understanding of the pathophysiology underlying these two overlapping conditions. Cases were identified using the HIPE Code at Tallaght Hospital from 1990-2014 and retrospective review was performed. Seven patients with both HS and CD were identified, 5(71%) female. The median age of diagnosis with both conditions was 37 years. In all cases, CD had preceded the diagnosis of HS. All patients smoked. Six had an increased BMI and 43% had additional autoimmune conditions. All patients required treatment with a TNF-alpha inhibitor for HS with 5 of 6 subjects having reduced frequency of flare ups and clinically less active HS on follow up.


Sujet(s)
Maladie de Crohn/complications , Hidrosadénite suppurée/complications , Adulte , Études de cohortes , Femelle , Hidrosadénite suppurée/traitement médicamenteux , Humains , Mâle , Plan de recherche , Études rétrospectives
9.
Clin Exp Dermatol ; 39(8): 900-3, 2014 Dec.
Article de Anglais | MEDLINE | ID: mdl-25224250

RÉSUMÉ

We describe two patients with newly diagnosed dermatoses localizing to the radiotherapy field following treatment for breast cancer. Patient 1 was a 53-year-old woman who developed bullous morphoea on her left breast two years after radiotherapy. Patient 2 was a 43-year-old woman who developed urticaria pigmentosa on her right breast eight months after radiotherapy and similar lesions gradually developed beyond the radiotherapy field. Both patients experienced a significant delay in diagnosis due to diagnostic confusion and concern over breast cancer recurrence. Irradiated skin demonstrates gradual and sustained alterations in fibrosis due to the production of long-lived cytokines and chemokines. These changes can induce a koebnerizing response in conditions such as morphoea and urticaria pigmentosa. We explore the mechanisms behind radiotherapy-induced skin changes, and highlight the potential for radiotherapy to exacerbate or unmask underlying dermatoses and systemic disease in the months and years following treatment.


Sujet(s)
Lésions radiques/complications , Dermatoses vésiculobulleuses/étiologie , Urticaire pigmentaire/étiologie , Adulte , Tumeurs du sein/radiothérapie , Femelle , Humains , Adulte d'âge moyen
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