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1.
Public Health ; 230: 29-37, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38484623

RESUMO

OBJECTIVES: The Making Every Contact Count (MECC) initiative is broadly defined as an opportunistic approach to prevention by making use of the thousands of conversations service providers have with service users every day. However, since its conception, the application of MECC has diverged and developed considerably. Thus, the current study aimed to revise the definition according to current research and practice to better describe what is and is not included. STUDY DESIGN: A consensus building classic Delphi methodology, completed by an expert panel. METHODS: Round 1 asked open questions around the definition of MECC. Content analysis of round 1 identified statements that were rated for agreement in round 2. Statements achieving ≥80% agreement were included in a short, long, or operational definition of MECC that were rated for agreement in round 3 (the minimum number required). An agreement of ≥80% indicated consensus. RESULTS: Forty out of 100 contacted experts completed three rounds. Experts in practice and research were recruited internationally although most were from England. From round 1, 274 statements were generated, of which 96 achieved consensus and were included within round 3. The short and long definition received consensus in round 3, the operational definition required four rounds to reach consensus. CONCLUSIONS: MECC is a person-centred approach to health behaviour change that, provided an individual possesses the relevant skills, can be delivered by anyone and anywhere. The distinguishing feature of MECC is not in its duration, target behaviour, or conditions for delivery, but rather in the approach taken and the mechanisms applied to conversations. Implications for research and practice are discussed, and the limits for applicability acknowledged.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Humanos , Consenso , Técnica Delphi , Projetos de Pesquisa , Inglaterra
2.
Int J Mol Sci ; 23(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36362138

RESUMO

Xylooligosaccharides (XOS) are widely used in the food industry as prebiotic components. XOS with high purity are required for practical prebiotic function and other biological benefits, such as antioxidant and inflammatory properties. In this work, we immobilized the recombinant endo-1,4-ß-xylanase of Malbranchea pulchella (MpXyn10) in various chemical supports and evaluated its potential to produce xylooligosaccharides (XOS) from hydrothermal liquor of eucalyptus wood chips. Values >90% of immobilization yields were achieved from amino-activated supports for 120 min. The highest recovery values were found on Purolite (142%) and MANAE-MpXyn10 (137%) derivatives, which maintained more than 90% residual activity for 24 h at 70 °C, while the free-MpXyn10 maintained only 11%. In addition, active MpXyn10 derivatives were stable in the range of pH 4.0−6.0 and the presence of the furfural and HMF compounds. MpXyn10 derivatives were tested to produce XOS from xylan of various sources. Maximum values were observed for birchwood xylan at 8.6 mg mL−1 and wheat arabinoxylan at 8.9 mg mL−1, using Purolite-MpXyn10. Its derivative was also successfully applied in the hydrolysis of soluble xylan present in hydrothermal liquor, with 0.9 mg mL−1 of XOS after 3 h at 50 °C. This derivative maintained more than 80% XOS yield after six cycles of the assay. The results obtained provide a basis for the application of immobilized MpXyn10 to produce XOS with high purity and other high-value-added products in the lignocellulosic biorefinery field.


Assuntos
Eucalyptus , Xilanos , Madeira , Glucuronatos , Oligossacarídeos/química , Endo-1,4-beta-Xilanases , Prebióticos , Hidrólise
3.
J Fish Biol ; 96(1): 49-58, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31648365

RESUMO

The aim of the present study was to perform comparative histological analyses of the ontogenetic development of two fish species endemic to the São Francisco River in Brazil: Prochilodus argenteus and Lophiosilurus alexandri. Histological analyses were performed every 24 h from the moment of hatching until 14 days post-hatching (dph) for the observation of larval development and until 39 dph for the observation of gonadal development. Whole larvae were fixed in Bouin's solution and the histological slides were stained with haematoxylin-eosin. Lophiosilurus alexandri larvae had a larger body size compared with P. argenteus larvae since hatching. Lophiosilurus alexandri larvae had mouth opening and pigmentation of the eyes upon hatching, whereas these events were observed at 1 dph in P. argenteus larvae. The visualisation and the inflation of the swim bladder occurred at 1 and 3 dph, respectively, in the P. argenteus, whereas these events occurred at 2 and 8 dph, respectively, in L. alexandri. Yolk granules were absorbed at 4 dph in P. argenteus and the 10 dph in L. alexandri. At 7 dph, the digestive tube was more differentiated in L. alexandri than P. argenteus and at 14 dph, the digestive system of both species had features of their eating habits: broad stomach and short intestine in L. alexandri, typical of carnivorous habits; stomach with a mechanical function and long intestine in P. argenteus, typical of detritivorous habits. The epithelial lining tissue, formed by a single layer of cells in the newly hatched larvae (0 dph), differentiated throughout the study, exhibiting scales in P. argenteus and numerous club cells in the middle epithelial region of L. alexandri at 39 dph. Undifferentiated gonads with somatic cells and primordial germ cells were observed at 39 dph, with caudal-cranial migration since 1 dph in both species. The anatomic changes during the ontogeny of P. argenteus and L. alexandri larvae are directly associated with the evolutionary history of each species, which explains their feeding habits, behaviour and distribution in the environment: Prochilodus argenteus is detritivorous and actively swims in the water column, whereas L. alexandri is carnivorous and inhabits bottom regions. At 39 dph neither species exhibited sexual differentiation.


Assuntos
Peixes-Gato/crescimento & desenvolvimento , Caraciformes/crescimento & desenvolvimento , Animais , Evolução Biológica , Brasil , Peixes-Gato/genética , Caraciformes/genética , Larva/genética , Larva/crescimento & desenvolvimento , Rios
5.
Fish Shellfish Immunol ; 60: 502-508, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27840170

RESUMO

Intestine mast cells/eosinophilic granule cells (MCs/EGC) of the marine species Centropomus parallelus (fat snook) were first studied using light and electron microscopy techniques. Mast cells are cells from the connective tissue found in almost all organs and tissues of vertebrates. In fish, they appear in greater numbers in parts of their bodies that are exposed to their environment, such as skin, gills and intestine. The granules in fat snook's mast cell contain a variety of substances, such as histamine, heparin, chondroitin sulfate, serotonin, proteases and cytokines. The present study of intestine MCs/EGC was carried out in 20 specimens of fat snook. Samples of tissue were fixed in Bouin solution and in buffered formalin. Ferric hematoxylin - Congo red, pH6 acridine orange, pH2.5 and pH0,5 Alcian Blue (AB), toluidine blue, PAS, AB + PAS and immunohistochemistry protocols were used. In the mucosa and submucosa layers, MCs/EGCs granules with basic contents were evidenced by Congo red staining, and with acid contents granules were identified through pH 2.5 and 0,5 AB, and acridine orange. Basic and acid contents were simultaneously evidenced using ferric hematoxylin - Congo red stain. Metachromasia was observed in both mucosal and submucosal mast cells. Neutral glycoproteins were evidenced by using PAS protocol, glycosaminoglycan through AB and both simultaneously through AB + PAS. In immunohistochemistry assays, MCs/EGC were positive for tryptase, chymase and serotonin. As in mammals, the study of samples fixed in modified Karnovsky for transmission electron microscopy evidenced that most of the MCs granules were spherical and showed varying electron density, as described in previous reports on other teleost fish species. The metachromasia observed and the identification of tryptase, chymase and serotonin suggest a great similarity between fat snook's MCs/EGC and those described in the mucosa of mammals.


Assuntos
Eosinófilos/citologia , Mastócitos/citologia , Perciformes/imunologia , Animais , Eosinófilos/ultraestrutura , Imuno-Histoquímica/veterinária , Intestinos/citologia , Intestinos/ultraestrutura , Mastócitos/ultraestrutura , Microscopia Eletrônica de Transmissão/veterinária , Coloração e Rotulagem/veterinária
6.
BMC Complement Altern Med ; 17(1): 376, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28754099

RESUMO

BACKGROUND: In northeastern Brazil, grape pomace has become a potential alternative byproduct because of the recover phenolic compounds from the vinification process. Comparative analyses were performed between lyophilized extract of grape skins from pomace, described as fermented (FGS), and fresh, unfermented (UGS) grape skins to show the relevant brand's composition upon the first maceration in winemaking. METHODS: The use of in vitro testing such as Folin-Ciocalteu's, DPPH free radical scavenger and HPLC methods were performed to evidence antioxidant effect and phenolic compounds. Additionally, vascular reactivity studies were performed in third-order branches of rat superior mesenteric arteries, which were obtained and placed in organ baths containing Krebs-Henseleit solution, maintained at 37 °C, gassed with a mixture of 95% O2 and 5% CO2, and maintained at pH 7.4. The in situ formation of reactive oxygen species (ROS) was evaluated in small mesenteric rings using oxidative fluorescent dihydroethidium dye. RESULTS: We found higher phenolic content and antioxidant activity in FGS when compared to UGS. HPLC analyses identified a significant number of phenolic compounds with antioxidant potential in both samples. The vasorelaxant effect induced by FGS was more potent than that induced by UGS, and the activity was attenuated after removal of vascular endothelium or by blockade of endothelium-derived relaxing factors, such as NO and EDHF. CONCLUSIONS: The FGS extract may be a great source of natural polyphenol products with potent antioxidant effects and endothelium-dependent vasodilatory actions involving NO and EDHF pathways.


Assuntos
Antioxidantes/farmacologia , Frutas/química , Fenóis/farmacologia , Epiderme Vegetal/química , Extratos Vegetais/farmacologia , Vasodilatadores/farmacologia , Vitis/química , Animais , Antioxidantes/análise , Artérias/efeitos dos fármacos , Artérias/fisiologia , Compostos de Bifenilo/metabolismo , Brasil , Cromatografia Líquida de Alta Pressão , Fermentação , Fenóis/análise , Picratos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Vasodilatadores/análise
7.
J Eukaryot Microbiol ; 63(5): 610-22, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26932133

RESUMO

We described the phylogenetic affiliation, development in cultures and ultrastructural features of a trypanosome of Leptodacylus chaquensis from the Pantanal biome of Brazil. In the inferred phylogeny, this trypanosome nested into the Anura clade of the basal Aquatic clade of Trypanosoma, but was separate from all known species within this clade. This finding enabled us to describe it as Trypanosoma herthameyeri n. sp., which also infects other Leptodacylus species from the Pantanal and Caatinga biomes. Trypanosoma herthameyeri multiplies as small rounded forms clumped together and evolving into multiple-fission forms and rosettes of epimastigotes released as long forms with long flagella; scarce trypomastigotes and glove-like forms are common in stationary-phase cultures. For the first time, a trypanosome from an amphibian was observed by field emission scanning electron microscopy, revealing a cytostome opening, well-developed flagellar lamella, and many grooves in pumpkin-like forms. Transmission electron microscopy showed highly developed Golgi complexes, relaxed catenation of KDNA, and a rich set of spongiome tubules in a regular parallel arrangement to the flagellar pocket as confirmed by electron tomography. Considering the basal position in the phylogenetic tree, developmental and ultrastructural data of T. herthameyeri are valuable for evolutionary studies of trypanosome architecture and cell biology.


Assuntos
Anuros/parasitologia , Filogenia , Trypanosoma/classificação , Trypanosoma/ultraestrutura , Tripanossomíase/veterinária , Animais , Anuros/sangue , Biodiversidade , Brasil , Classificação , DNA de Protozoário/genética , Ecologia , Ecossistema , Tomografia com Microscopia Eletrônica/métodos , Flagelos/ultraestrutura , Complexo de Golgi/ultraestrutura , Especificidade de Hospedeiro , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Trypanosoma/crescimento & desenvolvimento , Trypanosoma/isolamento & purificação , Tripanossomíase/sangue , Tripanossomíase/diagnóstico , Tripanossomíase/parasitologia
8.
Ann Surg Oncol ; 22(12): 3970-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25752894

RESUMO

BACKGROUND: The ability to provide accurate prognostic and predictive information to patients is becoming increasingly important as clinicians enter an era of personalized medicine. For a disease as heterogeneous as epithelial ovarian cancer, conventional algorithms become too complex for routine clinical use. This study therefore investigated the potential for an artificial intelligence model to provide this information and compared it with conventional statistical approaches. METHODS: The authors created a database comprising 668 cases of epithelial ovarian cancer during a 10-year period and collected data routinely available in a clinical environment. They also collected survival data for all the patients, then constructed an artificial intelligence model capable of comparing a variety of algorithms and classifiers alongside conventional statistical approaches such as logistic regression. RESULTS: The model was used to predict overall survival and demonstrated that an artificial neural network (ANN) algorithm was capable of predicting survival with high accuracy (93 %) and an area under the curve (AUC) of 0.74 and that this outperformed logistic regression. The model also was used to predict the outcome of surgery and again showed that ANN could predict outcome (complete/optimal cytoreduction vs. suboptimal cytoreduction) with 77 % accuracy and an AUC of 0.73. CONCLUSIONS: These data are encouraging and demonstrate that artificial intelligence systems may have a role in providing prognostic and predictive data for patients. The performance of these systems likely will improve with increasing data set size, and this needs further investigation.


Assuntos
Algoritmos , Neoplasias Epiteliais e Glandulares/cirurgia , Redes Neurais de Computação , Neoplasias Ovarianas/cirurgia , Área Sob a Curva , Teorema de Bayes , Carcinoma Epitelial do Ovário , Procedimentos Cirúrgicos de Citorredução , Árvores de Decisões , Feminino , Humanos , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Máquina de Vetores de Suporte , Taxa de Sobrevida
9.
Molecules ; 19(7): 9773-85, 2014 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-25006785

RESUMO

It has been established that oximes cause endothelium-independent relaxation in blood vessels. In the present study, the cardiovascular effects of the new oxime 3-hydroxy-4-(hydroxyimino)-2-(3-methylbut-2-enylnaphtalen-1(4H)-one (Oxime S1) derived from lapachol were evaluated. In normotensive rats, administration of Oxime S1 (10, 15, 20 and 30 mg/Kg, i.v.) produced dose-dependent reduction in blood pressure. In isolated aorta and superior mesenteric artery rings, Oxime S1 induced endothelium-independent and concentration-dependent relaxations (10(-8) M to 10(-4) M). In addition, Oxime S1-induced vasorelaxations were attenuated by hydroxocobalamin or methylene blue in aorta and by PTIO or ODQ in mesenteric artery rings, suggesting a role for the nitric oxide (NO) pathway. Additionally, Oxime S1 (30 and 100 µM) significantly increased NO concentrations (13.9 ± 1.6 nM and 17.9 ± 4.1 nM, respectively) measured by nitric oxide microsensors. Furthermore, pre-contraction with KCl (80 mM) prevented Oxime S1-derived vasorelaxation in endothelium-denuded aortic rings. Of note, combined treatment with potassium channel inhibitors also reduced Oxime S1-mediated vasorelaxation suggesting a role for potassium channels, more precisely Kir, Kv and KATP channels. We observed the involvement of BKCa channels in Oxime S1-induced relaxation in mesenteric artery rings. In conclusion, these data suggest that the Oxime S1 induces hypotension and vasorelaxation via NO pathway by activating soluble guanylate cyclase (sGC) and K+ channels.


Assuntos
GMP Cíclico/metabolismo , Guanilato Ciclase/metabolismo , Naftoquinonas/farmacologia , Óxido Nítrico/metabolismo , Oximas/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Vasodilatadores/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Naftoquinonas/química , Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/farmacologia , Oximas/química , Canais de Potássio/metabolismo , Ratos , Guanilil Ciclase Solúvel , Vasodilatadores/química
10.
AJNR Am J Neuroradiol ; 45(8): 1070-1075, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-38991766

RESUMO

BACKGROUND AND PURPOSE: Morning glory disc anomaly (MGDA) is a congenital malformation characterized by a funnel-shaped optic disc excavation with radiating vessels and a central glial tuft. Imaging is essential to evaluate associated cephalocele and steno-occlusive vasculopathy. The goal of this study was to assess optic nerve, chiasmatic, and sphenoid bone morphology in MGDA. MATERIALS AND METHODS: This retrospective study examined all subjects with funduscopically confirmed MGDA diagnosed and imaged with brain MR imaging between 2008 and 2023. RESULTS: Thirty-two children met inclusion criteria. Ocular involvement was unilateral in 29 subjects and bilateral in 3. Segmental optic nerve enlargement ipsilateral to the MGDA was seen in 21 subjects, with 3 also demonstrating a segmental reduction in the size of the ipsilateral optic nerve. Segmental reduction in the size of the ipsilateral optic nerve was present in 3 additional subjects, one with bilateral MGDA. The optic chiasm appeared asymmetrically thickened in 21 subjects, often with deformity. The optic nerves appeared normal in signal intensity in all subjects, with faint peripheral chiasmatic enhancement in 4 of 20 patients who received contrast. Optic nerve findings were stable in 15 subjects with multiple examinations. A persistent craniopharyngeal canal was identified in 17 subjects with sphenoid cephalocele in 1 and mild inferior pituitary gland displacement in 4. Tubular or nodular nasopharyngeal lesions were seen in 10 subjects. One subject had an off-midline sphenoid bone cleft, midbrain deformity, and abnormal thickening of and enhancement around the left oculomotor nerve; the oculomotor nerve finding was present in 1 additional patient. CONCLUSIONS: MGDA often manifests with ipsilateral optic nerve thickening, leading to a potential misdiagnosis as optic glioma. MGDA is also commonly associated with a persistent craniopharyngeal canal with variable pituitary gland and infundibular deformity, cephalocele, and tubular or nodular nasopharyngeal lesions.


Assuntos
Imageamento por Ressonância Magnética , Disco Óptico , Humanos , Feminino , Masculino , Estudos Retrospectivos , Criança , Imageamento por Ressonância Magnética/métodos , Disco Óptico/diagnóstico por imagem , Disco Óptico/anormalidades , Disco Óptico/patologia , Pré-Escolar , Adolescente , Lactente , Fenótipo , Osso Esfenoide/diagnóstico por imagem , Osso Esfenoide/anormalidades , Osso Esfenoide/patologia , Quiasma Óptico/diagnóstico por imagem , Quiasma Óptico/anormalidades , Quiasma Óptico/patologia , Anormalidades do Olho/diagnóstico por imagem , Anormalidades do Olho/patologia
11.
Transl Psychiatry ; 14(1): 417, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39366962

RESUMO

Sleep disruption and negative affect are attendant features of many psychiatric and neurological conditions that are often co-morbid including major depressive disorder, generalized anxiety disorder and chronic pain. Whether there is a causal relationship between negative affect and sleep disruption remains unclear. We therefore asked if mechanisms promoting negative affect can disrupt sleep and whether inhibition of pathological negative affect can normalize disrupted sleep. Signaling at the kappa opioid receptor (KOR) elicits dysphoria in humans and aversive conditioning in animals. We tested the possibility that (a) increased KOR signaling in the anterior cingulate cortex (ACC), a brain region associated with negative emotions, would be sufficient to promote both aversiveness and sleep disruption and (b) inhibition of KOR signaling would normalize pathological negative affect and sleep disruption induced by chronic pain. Chemogenetic Gi-mediated inhibition of KOR-expressing ACC neurons produced conditioned place aversion (CPA) as well as sleep fragmentation in naïve mice. CRISPR/Cas9 editing of ACC KOR normalized both the negative affect and sleep disruption elicited by pathological chronic pain while maintaining the physiologically critical sensory features of pain. These findings suggest therapeutic utility of KOR antagonists for treatment of disease conditions that are associated with both negative affect and sleep disturbances.


Assuntos
Dor Crônica , Giro do Cíngulo , Receptores Opioides kappa , Animais , Receptores Opioides kappa/metabolismo , Receptores Opioides kappa/genética , Camundongos , Giro do Cíngulo/metabolismo , Giro do Cíngulo/fisiopatologia , Masculino , Dor Crônica/metabolismo , Dor Crônica/fisiopatologia , Transtornos do Sono-Vigília/metabolismo , Transtornos do Sono-Vigília/fisiopatologia , Camundongos Endogâmicos C57BL , Afeto/fisiologia
12.
Brain Commun ; 6(2): fcae051, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444905

RESUMO

Migraine and sleep disorders are common co-morbidities. Patients frequently link their sleep to migraine attacks suggesting a potential causal relationship between these conditions. However, whether migraine pain promotes or disrupts sleep or whether sleep disruption can increase the risk of migraine remains unknown. We assessed the potential impact of periorbital allodynia, a measure consistent with migraine-like pain, from multiple preclinical models on sleep quantity and quality. Additionally, we evaluated the possible consequences of sleep deprivation in promoting susceptibility to migraine-like pain. Following the implantation of electroencephalogram/electromyography electrodes to record sleep, mice were treated with either single or repeated systemic injections of nitroglycerin at the onset of their active phase (i.e. nocturnal awake period). Neither single nor repeated nitroglycerin affected the total sleep time, non-rapid eye movement sleep, rapid eye movement sleep, sleep depth or other measures of sleep architecture. To account for the possible disruptive effects of the surgical implantation of electroencephalogram/electromyography electrodes, we used immobility recordings as a non-invasive method for assessing sleep-wake behaviour. Neither single nor repeated nitroglycerin administration during either the mouse sleep (i.e. daylight) or active (i.e. night) periods influenced immobility-defined sleep time. Administration of an inflammatory mediator mixture onto the dura mater at either sleep or active phases also did not affect immobility-defined sleep time. Additionally, inhalational umbellulone-induced migraine-like pain in restraint-stressed primed mice did not alter immobility-defined sleep time. The possible influence of sleep disruption on susceptibility to migraine-like pain was evaluated by depriving female mice of sleep over 6 h with novel objects, a method that does not increase circulating stress hormones. Migraine-like pain was not observed following acute sleep deprivation. However, in sleep-deprived mice, subthreshold doses of systemic nitroglycerin or dural calcitonin gene-related peptide induced periorbital cutaneous allodynia consistent with migraine-like pain. Our data reveal that while migraine-like pain does not significantly disrupt sleep, sleep disruption increases vulnerability to migraine-like pain suggesting that a therapeutic strategy focused on improving sleep may diminish migraine attacks.

13.
Int J Biol Macromol ; 280(Pt 2): 135816, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39306183

RESUMO

Acetylxylan esterases (AXEs) are essential enzymes that break down the acetyl groups in acetylated xylan found in plant cell walls polysaccharides. They work synergistically with backbone-depolymerizing xylanolytic enzymes to accelerate the degradation of complex polysaccharides. In this study, we cloned the gene axeA, which encodes the acetylxylan esterase from Aspergillus nidulans FGSC A4 (AxeAN), into the pEXPYR expression vector and introduced it into the high protein-producing strain A. nidulans A773. The purified AxeAN, with a molecular weight of 33.5 kDa as confirmed by SDS-PAGE, was found to be active on ρ-nitrophenyl acetate (ρNPA), exhibiting a remarkably high specific activity (170 U mg-1) at pH 7.0 and 55 °C. AxeAN demonstrated stability over a wide pH range (5.5-9.0), retaining >80% of its initial activity after 24 h. The KM and Vmax were 0.098 mmol L-1 and 320 U mg-1, respectively, using ρNPA as a substrate. We also evaluated the synergistic effect of AxeAN with an endo-1,4-ß-xylanase from Malbranchea pulchella (MpXyn10) in the hydrolysis of four different xylans (Birchwood, Beechwood, Oat spelt, and Arabinoxylan) to produce xylooligosaccharides (XOS). The best results were obtained using Birchwood xylan as substrate and MpXyn10-AxeAN as biocatalysts after 24 h of reaction (50 °C), with a XOS-yield of 91%, value 41% higher when compared to MpXyn10 (XOS-yield of 63%). These findings showed the potential of the application of AxeAN, together with other xylanases, to produce xylooligosaccharides with high purity and other products with high added value in the field of lignocellulosic biorefinery.

14.
Bioresour Bioprocess ; 11(1): 77, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073555

RESUMO

The ß-glucosidase gene from Aspergillus nidulans FGSC A4 was cloned and overexpressed in the A. nidulans A773. The resulting purified ß-glucosidase, named AnGH3, is a monomeric enzyme with a molecular weight of approximately 80 kDa, as confirmed by SDS-PAGE. Circular dichroism further validated its unique canonical barrel fold (ß/α), a feature also observed in the 3D homology model of AnGH3. The most striking aspect of this recombinant enzyme is its robustness, as it retained 100% activity after 24 h of incubation at 45 and 50 ºC and pH 6.0. Even at 55 °C, it maintained 72% of its enzymatic activity after 6 h of incubation at the same pH. The kinetic parameters Vmax, KM, and Kcat/KM for ρ-nitrophenyl-ß-D-glucopyranoside (ρNPG) and cellobiose were also determined. Using ρNPG, the enzyme demonstrated a Vmax of 212 U mg - 1, KM of 0.0607 mmol L - 1, and Kcat/KM of 4521 mmol L - 1 s - 1 when incubated at pH 6.0 and 65 °C. The KM, Vmax, and Kcat/KM using cellobiose were 2.7 mmol L - 1, 57 U mg - 1, and 27 mmol -1 s - 1, respectively. AnGH3 activity was significantly enhanced by xylose and ethanol at concentrations up to 1.5 mol L - 1 and 25%, respectively. Even in challenging conditions, at 65 °C and pH 6.0, the enzyme maintained its activity, retaining 100% and 70% of its initial activity in the presence of 200 mmol L - 1 furfural and 5-hydroxymethylfurfural (HMF), respectively. The potential of this enzyme was further demonstrated by its application in the saccharification of the forage grass Panicum maximum, where it led to a 48% increase in glucose release after 24 h. These unique characteristics, including high catalytic performance, good thermal stability in hydrolysis temperature, and tolerance to elevated concentrations of ethanol, D-xylose, furfural, and HMF, position this recombinant enzyme as a promising tool in the hydrolysis of lignocellulosic biomass as part of an efficient multi-enzyme cocktail, thereby opening new avenues in the field of biotechnology and enzymology.

15.
Br J Cancer ; 109(4): 950-6, 2013 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-23880823

RESUMO

BACKGROUND: Evidence increasingly supports that prostate cancer is initiated by the malignant transformation of stem cells (SCs). Furthermore, many SC-signalling pathways are shown to be shared in prostate cancer. Therefore, we planned transcriptome characterisation of adult prostate SCs as a strategy to consider new targets for cancer treatment. METHODS: Intuitive pathway analysis was used for putative target discovery in 12 matched selections of human prostate SCs, transiently amplifying cells and terminally differentiated cells. These were pooled into three groups according to the stage of differentiation for mRNA microarray analysis. Targets identified were validated using uncultured primary tissue (n=12), functional models of prostate cancer and a tissue microarray consisting of benign (n=42) and malignant prostate (n=223). RESULTS: A deficiency in class 1 UDP glucuronosyltransferase (UGT) enzymes (UGT1A) was identified in prostate SCs, which are involved in androgen catabolism. Class 1 UGT enzyme expression was also downregulated in cancer SCs and during progression to metastatic castration-resistant prostate cancer (CRPC). Reduction of UGT1A expression in vitro was seen to improve cell survival and increase androgen receptor (AR) activity, as shown by upregulation of prostate-specific antigen expression. INTERPRETATION: Inactivation of intracellular androgen catabolism represents a novel mechanism to maintain AR activity during CRPC.


Assuntos
Células-Tronco Adultas/enzimologia , Regulação Neoplásica da Expressão Gênica , Glucuronosiltransferase/genética , Células-Tronco Neoplásicas/enzimologia , Próstata/enzimologia , Neoplasias da Próstata/enzimologia , RNA Mensageiro/análise , Androgênios/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação para Baixo , Perfilação da Expressão Gênica , Glucuronosiltransferase/metabolismo , Humanos , Calicreínas/metabolismo , Masculino , Próstata/citologia , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Androgênicos/metabolismo , Transcriptoma , Regulação para Cima
16.
J Cardiovasc Pharmacol ; 62(1): 58-66, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23842292

RESUMO

For many years, nitric oxide (NO) has been studied as an important mediator in the control of vascular tone. Endothelial deficiencies that diminish NO production can result in the development of several future cardiovascular diseases, such as hypertension and arteriosclerosis. In this context, new drugs with potential ability to donate NO have been studied. In this study, 3 aromatic oximes [benzophenone oxime, 4-Cl-benzophenone oxime, and E-cinnamaldehyde oxime (E-CAOx)] induced vasorelaxation in endothelium-denuded and intact superior mesenteric rings precontracted with phenylephrine. E-CAOx demonstrated the most potent effect, and its mechanism of action was evaluated. Vascular reactivity experiments demonstrated that the effect of E-CAOx was reduced by the presence of 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, 1H[1,2,4,]oxadiazolo[4,3-a]quinoxalin-1-one, and (Rp)-8-(para-chlorophenylthio)guanosine-3',5'-cyclic monophosphorothioate, suggesting the participation of NO/sGC/PKG pathway. NO donation seems to be mediated through nicatinamide adenine dinucleotide phosphate-dependent reductases because 7-ethoxyresorufin decreased the effect of E-CAOx on vascular reactivity and reduced NO formation as detected by flow cytometry using the NO indicator diaminofluorescein 4,5-diacetate. Further downstream of NO donation, K+ subtype channels were also shown to be involved in the E-CAOx vasorelaxant effect. The present study showed that E-CAOx acts like an NO donor, activating NO/sGC/PKG pathway and thus K+ channels.


Assuntos
Acroleína/análogos & derivados , Artéria Mesentérica Superior/efeitos dos fármacos , Óxido Nítrico/fisiologia , Transdução de Sinais/efeitos dos fármacos , Acroleína/farmacologia , Animais , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Endotélio Vascular/fisiologia , Inibidores Enzimáticos/farmacologia , Técnicas In Vitro , Contração Isométrica/efeitos dos fármacos , Luminescência , Masculino , Relaxamento Muscular/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Oximas/farmacologia , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/fisiologia , Ratos , Ratos Wistar
17.
Temperature (Austin) ; 10(1): 121-135, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37187830

RESUMO

Thermoregulatory behaviors are powerful effectors for core body temperature (Tc) regulation. We evaluated the involvement of afferent fibers ascending through the dorsal portion of the lateral funiculus (DLF) of the spinal cord in "spontaneous" thermal preference and thermoregulatory behaviors induced by thermal and pharmacological stimuli in a thermogradient apparatus. In adult Wistar rats, the DLF was surgically severed at the first cervical vertebra bilaterally. The functional effectiveness of funiculotomy was verified by the increased latency of tail-flick responses to noxious cold (-18°C) and heat (50°C). In the thermogradient apparatus, funiculotomized rats showed a higher variability of their preferred ambient temperature (Tpr) and, consequently, increased Tc fluctuations, as compared to sham-operated rats. The cold-avoidance (warmth-seeking) response to moderate cold (whole-body exposure to ~17°C) or epidermal menthol (an agonist of the cold-sensitive TRPM8 channel) was attenuated in funiculotomized rats, as compared to sham-operated rats, and so was the Tc (hyperthermic) response to menthol. In contrast, the warmth-avoidance (cold-seeking) and Tc responses of funiculotomized rats to mild heat (exposure to ~28°C) or intravenous RN-1747 (an agonist of the warmth-sensitive TRPV4; 100 µg/kg) were unaffected. We conclude that DLF-mediated signals contribute to driving spontaneous thermal preference, and that attenuation of these signals is associated with decreased precision of Tc regulation. We further conclude that thermally and pharmacologically induced changes in thermal preference rely on neural, presumably afferent, signals that travel in the spinal cord within the DLF. Signals conveyed by the DLF are important for cold-avoidance behaviors but make little contribution to heat-avoidance responses.

18.
Ultrasound Obstet Gynecol ; 40(5): 522-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22262510

RESUMO

OBJECTIVE: To assess neurodevelopmental outcome of fetuses diagnosed with callosal abnormalities after referral for ventriculomegaly. METHODS: This sub-analysis of a prospective study of 430 fetuses, which were referred for ventriculomegaly and underwent sonography and magnetic resonance imaging (MRI), included those fetuses with a diagnosis of corpus callosal abnormalities after recruitment into the main study. Between three and six radiologists independently reviewed ultrasound and MR images and recorded central nervous system (CNS) abnormalities, with final diagnoses being decided by consensus. Postnatal outcomes of fetuses with callosal abnormalities were compared between those with and those without other abnormalities. RESULTS: Callosal abnormalities were detected in 13% (58/430) of the fetuses referred with ventriculomegaly. Callosal dysgenesis was isolated in 24% (14/58) of these cases, with the remainder complicated by CNS, karyotypic or other major abnormalities. Five fetuses diagnosed prenatally as having isolated callosal abnormalities had additional CNS findings on postnatal assessment. Preconference kappa for callosal abnormalities was 0.76 for ultrasound and 0.78 for MRI, indicating that these investigations had a similar level of operator dependence. Neurodevelopmental outcome was normal or showed only mild delay that resolved in 67% (8/12) children with isolated callosal abnormalities compared to 7% (2/27) in those with non-isolated callosal abnormalities (P = 0.003). CONCLUSION: Callosal abnormalities are present in a significant proportion of fetuses with a diagnosis of ventriculomegaly. Isolated callosal abnormalities are associated with normal neurodevelopmental outcome in approximately two-thirds of fetuses.


Assuntos
Agenesia do Corpo Caloso/diagnóstico , Ventrículos Cerebrais/anormalidades , Imageamento por Ressonância Magnética/métodos , Resultado da Gravidez , Ultrassonografia Pré-Natal/métodos , Adulto , Agenesia do Corpo Caloso/diagnóstico por imagem , Feminino , Humanos , Gravidez , Estudos Prospectivos , Estatísticas não Paramétricas
19.
AJNR Am J Neuroradiol ; 43(11): 1646-1652, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36175083

RESUMO

BACKGROUND AND PURPOSE: An "unwound" or "offset" cochlea has been described as a characteristic imaging feature in patients with branchio-oto-renal syndrome, and recently recognized to be associated in particular to those with EYA1 gene mutations. Determination of this feature has traditionally relied on subjective visual assessment. Our aim was to establish an objective assessment method for cochlear offset (the cochlear turn alignment ratio) and determine an optimal cutoff turn alignment ratio value that separates individuals with EYA1-branchio-oto-renal syndrome from those with SIX1-branchio-oto-renal syndrome and healthy controls. MATERIALS AND METHODS: Temporal bone CT or MR imaging from 40 individuals with branchio-oto-renal syndrome and 40 controls was retrospectively reviewed. Cochlear offset was determined visually by 2 independent blinded readers and then quantitatively via a standardized technique yielding the cochlear turn alignment ratio. The turn alignment ratio values were compared between cochleae qualitatively assessed as "not offset" and "offset." Receiver operating characteristic analysis was used to determine the ability of the turn alignment ratio to differentiate between these populations and an optimal cutoff turn alignment ratio value. Cochlear offset and turn alignment ratio values were analyzed for each branchio-oto-renal syndrome genotype subpopulation and for controls. RESULTS: The turn alignment ratio can accurately differentiate between cochleae with and without an offset (P < .001). The optimal cutoff value separating these populations was 0.476 (sensitivity = 1, specificity = 0.986, J = 0.986). All except 1 cochlea among the EYA1-branchio-oto-renal syndrome subset and all with unknown genotype branchio-oto-renal syndrome had a cochlear offset and a turn alignment ratio of <0.476. All except 1 cochlea among the SIX1-branchio-oto-renal syndrome subset and all controls had no offset and a turn alignment ratio of >0.476. CONCLUSIONS: There is a statistically significant difference in turn alignment ratios between offset and nonoffset cochleae, with an optimal cutoff of 0.476. This cutoff value allows excellent separation of EYA1-branchio-oto-renal syndrome from SIX1-branchio-oto-renal syndrome and from individuals without branchio-oto-renal syndrome or sensorineural hearing loss. The turn alignment ratio is a reliable and objective metric that can aid in the imaging evaluation of branchio-oto-renal syndrome.


Assuntos
Síndrome Brânquio-Otorrenal , Humanos , Síndrome Brânquio-Otorrenal/diagnóstico por imagem , Síndrome Brânquio-Otorrenal/genética , Estudos Retrospectivos , Proteínas Tirosina Fosfatases/genética , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Nucleares/genética , Cóclea/diagnóstico por imagem , Mutação , Proteínas de Homeodomínio/genética
20.
AJNR Am J Neuroradiol ; 43(2): 309-314, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35058298

RESUMO

BACKGROUND AND PURPOSE: Temporal bone imaging plays an important role in the work-up of branchio-oto-renal syndrome. Previous reports have suggested that the unwound or offset cochlea is a highly characteristic marker for branchio-oto-renal syndrome. Our goals were to examine the prevalence of this finding in a branchio-oto-renal syndrome cohort and analyze genetic-phenotypic associations not previously established. MATERIALS AND METHODS: This multicenter retrospective study included 38 ears in 19 unrelated individuals with clinically diagnosed branchio-oto-renal syndrome and confirmed mutations in the EYA1 or SIX1 genes. Two blinded neuroradiologists independently reviewed and documented temporal bone imaging findings in 13 categories for each ear. Imaging phenotypes were correlated with genotypes. RESULTS: There was excellent interrater agreement for all 13 phenotypic categories (κ ≥ 0.80). Of these, 9 categories showed statistically significant differences between patients with EYA1-branchio-oto-renal syndrome and SIX1-branchio-oto-renal syndrome. Cochlear offset was present in 100% of patients with EYA1-branchio-oto-renal syndrome, but in only 1 ear (12.5%) among patients with SIX1-branchio-oto-renal syndrome. A short thorny appearance of the cochlear apical turn was observed in most patients with SIX1-branchio-oto-renal syndrome. CONCLUSIONS: An offset cochlea is associated with the EYA1-branchio-oto-renal syndrome genotype. The SIX1-branchio-oto-renal syndrome genotype is associated with a different cochlear phenotype that almost always is without offset and has a short thorny tip as the apical turn. Therefore, cochlear offset is not a characteristic marker for all patients with branchio-oto-renal syndrome. The lack of a cochlear offset in a patient with clinically suspected branchio-oto-renal syndrome does not exclude the diagnosis and, in fact, may be predictive of the SIX1 genotype.


Assuntos
Síndrome Brânquio-Otorrenal , Síndrome Brânquio-Otorrenal/diagnóstico por imagem , Síndrome Brânquio-Otorrenal/genética , Cóclea/diagnóstico por imagem , Estudos de Associação Genética , Proteínas de Homeodomínio/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Nucleares/genética , Proteínas Tirosina Fosfatases/genética , Estudos Retrospectivos
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