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1.
Nutr Cancer ; 73(3): 523-533, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32367766

RESUMEN

Intestinal mucositis (IM) caused by antineoplastic chemotherapy is characterized by an important inflammatory process, which may compromise ongoing treatment. Our study aimed to investigate the effect of Açaí (Euterpe oleracea Martius) on the antioxidant response in BALB/c mice pretreated with Açaí pulp (200 g/kg) for 14 day. A group of animals receiving a single intraperitoneal injection of 5-FU (200 mg/kg) were euthanized on day three (D3) or seven (D7) after administration, the distal jejunum was isolated for the analyses of histology, superoxide dismutase (SOD) and catalase (CAT) enzyme activities, and concentration of total sulfhydryl groups (GSH). Seven days after induction, the intake of Açaí by the IM group almost completely regenerated tissue histology. Notably, SOD activity decreased in the MUC + Açaí group (D3). CAT activity reduced on D3 and D7 in the IM groups and Açaí treatment groups, respectively. No change was observed in the total GSH concentration at the tissue level. Our results demonstrated the protective effect of Açaí pulp components on intestinal damage induced by 5-FU, as well as the ability to control the response to oxidative stress, in order to mobilize defense pathways and promote tissue repair.


Asunto(s)
Euterpe , Mucositis , Animales , Antioxidantes , Fluorouracilo , Yeyuno , Ratones , Ratones Endogámicos BALB C , Mucositis/inducido químicamente , Mucositis/tratamiento farmacológico , Extractos Vegetales/farmacología
2.
Int Endod J ; 53(10): 1430-1437, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32602578

RESUMEN

AIM: To evaluate the influence of various endodontic access cavity designs and the use of an operating microscope (OM) with or without ultrasonic troughing to detect middle mesial canals (MMCs) in extracted mandibular first molars. METHODOLOGY: Sixty extracted mandibular first molars were evaluated by cone beam computed tomography (CBCT) in order to detect the presence of MMCs and then divided into two groups (n = 30) with an equal proportion of 1 molar with MMC for each 3 molars. A specific access cavity design was performed for each group, either a conservative access cavity (CAC) or a traditional access cavity (TAC). Root canals were detected in three assessment stages: (i) no magnification, (ii) using an OM and (iii) using an OM together with ultrasonic troughing. Evaluations were performed on a mannequin head in an ergonomic working position. The confidence obtained in the assessment stages was portrayed by sensitivity, specificity and accuracy, calculated by the area under the ROC curve. The difference in the proportion of correct diagnoses in identifying the MMC using either CAC or TAC preparation, at each of the three stages, was checked using Cochran's Q tests. Binomial tests were performed at each stage to investigate whether there was a difference between the types of endodontic access designs to detect MMCs. Significance was set at P < 0.05. RESULTS: Accuracy increased at each assessment stage. At the third stage, both groups provided perfect accuracy (1.00). Cochran's Q tests indicated that the confidence of MMC detection for both TAC and CAC groups (P < 0.05) increased significantly at each stage. Binomial tests demonstrated that there was no significant difference between the TAC and CAC groups, when evaluation was performed without magnification (P > 0.05), with OM (P > 0.05), or with OM associated with ultrasonic troughing (P > 0.05). CONCLUSION: The access cavity design did not significantly affect detection of middle mesial canals in extracted mandibular first molars placed in a mannequin. However, the use of OM increased the accuracy of the MMC identification, especially when associated with ultrasonic troughing.


Asunto(s)
Cavidad Pulpar , Ultrasonido , Tomografía Computarizada de Haz Cónico , Cavidad Pulpar/diagnóstico por imagen , Mandíbula , Diente Molar/diagnóstico por imagen , Raíz del Diente
3.
Med Oral Patol Oral Cir Bucal ; 23(5): e524-e530, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30148466

RESUMEN

BACKGROUND: To review and discuss important topics regarding periodontal treatment pre- and post-radiotherapy for head and neck cancer in human patients; to discuss the references for adequate techniques, the appropriate moment for tooth extractions and periodontal management; and to discuss the prevention of osteoradionecrosis. MATERIAL AND METHODS: Thirty-nine studies including original studies, randomized clinical trials (RCTs) and reviews were searched in online databases MEDLINE (PubMed) and the Cochrane library. No year of publication restriction was applied. RESULTS: Language was restricted to English, and the following Medical Subject Heading terms were used: radiotherapy, radiation therapy and periodontal treatment. Studies regarding periodontal treatment and tooth extraction that involved clinical management of irradiated patients were selected. CONCLUSIONS: The treatment of periodontal diseases before radiotherapy is mainly required to avoid future dental extraction and to reduce the development of osteoradionecrosis. Periodontal treatment in irradiated patients mostly includes scaling and root planing, extraction of condemned teeth and topical and systemic antimicrobial therapy. Tooth removal should be planned at least 14 days before the first day of radiation treatment. Particular care and mouthwashes should be taken during and after radiation. CLINICAL SIGNIFICANCE: The management of irradiated patients represents a challenge for health professionals, including dentists. It is important to establish recommendations for clinicians concerning dental and periodontal management in irradiated patients before, during and after treatment.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Enfermedades Periodontales/terapia , Atención Odontológica , Humanos , Osteorradionecrosis/prevención & control
4.
Soft Matter ; 12(35): 7324-9, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27506248

RESUMEN

We present an approach which makes it possible to directly determine the bending modulus of single elongated block copolymer micelles. This is done by forming arrays of suspended micelles onto microfabricated substrates and by performing three-point bending flexural tests, using an atomic force microscope, on their suspended portions. By coupling the direct atomic force microscopy measurements with differential scanning calorimetry data, we show that the presence of a crystalline corona strongly increases the modulus of the copolymer elongated micelles. This large increase suggests that crystallites in the corona are larger and more uniformly oriented due to confinement effects. Our findings together with this hypothesis open new interesting avenues for the preparation of core-templated polymer fibres with enhanced mechanical properties.

5.
J Med Imaging Radiat Sci ; 55(2): 307-319, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38365469

RESUMEN

INTRODUCTION: The increasing global incidence rate of dementia and associated co/multimorbidity has consequently led to a rise in the number of people with dementia (PwD) requiring clinical radiography care services. This review aims to explore and integrate findings from diverse settings with a focus on the experiences of PwD and stakeholders, towards the development of a holistic approach for dementia care and management within the context of radiography services. METHOD: An electronic search was performed across the following databases: PUBMED, CINAHL, Medline, SCOPUS, and ScienceDirect for articles published from January 2009 and June 2023. Articles were included if they fulfilled a predefined criteria mainly focused on experiences of PwD and/or other stakeholders when using the radiography services. Data obtained from the included studies were analysed using a result-based convergent synthesis. RESULT: Eleven studies from diverse settings met the inclusion criteria. A mix of both positive and negative experiences of PwD and stakeholders were reported following visits to radiology and radiotherapy departments were highlighted across settings. The findings were themed around the need for: person-centred care, effective communication, attitudinal changes of staff, specialised and improved clinical environment and inclusion of caregivers for the care of PwD. DISCUSSION: This study emphasise the critical importance of adopting holistic approaches to caring for PwD. This involves adopting a person-centred approach, actively involving caregivers, effective communication, and adequate training for radiographers to provide quality services, all in dementia-friendly environments. CONCLUSION: The experiences of various stakeholders highlight the need for a more holistic approach and strategy for the care and management of PwD within the context of the radiography services. This calls for an urgent need for a comprehensive strategy that includes awareness creation of staff to enhance the quality of care and the overall experience for PwD using the radiography services.


Asunto(s)
Demencia , Humanos , Atención Dirigida al Paciente , Radiografía
6.
Transpl Infect Dis ; 15(1): 42-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22783905

RESUMEN

BACKGROUND: Respiratory syncytial virus (RSV) is a common cause of seasonal respiratory viral infection in hematopoietic stem cell transplantations (HSCT) patients. The efficacy of treatment, however, remains controversial. We describe an outbreak of 31 cases of RSV that occurred in an HSCT outpatient care unit in the fall season from March through May 2010, with a good outcome without any specific antiviral treatment. METHODS: During these 3 months, 222 nasal wash samples were tested and, of these, 31 outpatients were positive for RSV. In 2009, 99 samples had been tested and only 10 outpatients were positive for RSV in the same period. RESULTS: Seven (22.5%) patients had severe neutropenia (<500 cells/µL); severe lymphopenia (<200 cells/µL) was present in 13 (41.9%) patients, and 14 (45%) had received intravenous broad-spectrum antibiotics. Hospitalization was necessary only for 8 patients (25.8%); 20 had lower respiratory tract infection (64.5%). Only 1 patient died as a result of proven invasive aspergillosis. CONCLUSION: This report suggests that HSCT outpatients with no risk factors may not always require specific treatment for RSV.


Asunto(s)
Antivirales/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Pacientes Ambulatorios , Infecciones por Virus Sincitial Respiratorio/epidemiología , Adolescente , Adulto , Anciano , Niño , Infección Hospitalaria , Brotes de Enfermedades , Femenino , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Líquido del Lavado Nasal/virología , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Virus Sincitiales Respiratorios/aislamiento & purificación , Factores de Riesgo , Resultado del Tratamiento , Adulto Joven
7.
J Appl Microbiol ; 111(1): 224-32, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21496189

RESUMEN

AIMS: To investigate the distribution of the genes that encode enterotoxins and the colonization factors (CF) types as well as the antibiotic susceptibility profile of enterotoxigenic Escherichia coli (ETEC) isolated from children from the Brazilian Northeast. METHODS AND RESULTS: We conducted a 3·5-year prospective study that involved 250 children with and 150 without diarrhoea, aged 1-60 months, from low-income families in Teresina/Brazilian Northeast. All samples were assayed for E. coli, enterotoxin and CF genes and antimicrobial susceptibility by microbiological methods and PCR. ETEC strains were isolated from 9·2% children with and 4·0% without diarrhoea. Infection was more common in children aged 6-24 months in rainy months. elt⁺ /CFA/IV⁺ and elt⁺ /CS14⁺ were the most frequent genotypes. Susceptibility to nalidixic acid, ciprofloxacin and gentamicin and resistance to ampicillin, cephalothin and sulfamethoxazole-trimethoprim were common. CONCLUSIONS: elt ⁺isolates and ETEC strains harbouring genes encoding CFA/IV and CS/14 were the most common ETEC found in Brazilian Northeast. SIGNIFICANCE AND IMPACT OF THE STUDY: Our data, the first generated for north-eastern Brazilian children, may be important for the development of an effective vaccine and for facilitation of an empirical choice of antibiotic treatment or prophylaxis for traveller's diarrhoea in the area studied.


Asunto(s)
Diarrea/microbiología , Escherichia coli Enterotoxigénica/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Toxinas Bacterianas/genética , Brasil , Preescolar , Diarrea/tratamiento farmacológico , Diarrea Infantil/tratamiento farmacológico , Diarrea Infantil/microbiología , Escherichia coli Enterotoxigénica/efectos de los fármacos , Escherichia coli Enterotoxigénica/genética , Escherichia coli Enterotoxigénica/patogenicidad , Infecciones por Escherichia coli/tratamiento farmacológico , Proteínas de Escherichia coli/genética , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Factores de Virulencia/genética
8.
Benef Microbes ; 12(2): 187-197, 2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33789554

RESUMEN

Asthma is an inflammatory lung disease that affects more women than men in adulthood. Clinical evidence shows that hormonal fluctuation during the menstrual cycle and menopause are related to increased asthma severity in women. Considering that life expectancy has increased and that most women now undergo menopause, strategies to prevent the worsening of asthma symptoms are particularly important. A recent study from our group showed that re-exposure of ovariectomised allergic mice to antigen (ovalbumin) leads to an exacerbation of lung inflammation that is similar to clinical conditions. However, little is known about the role of probiotics in the prevention of asthma exacerbations during the menstrual cycle or menopause. Thus, our objective was to evaluate the effects of supplementation with kefir, a popular fermented dairy beverage, as a preventive strategy for modulating allergic disease. The results show that the preventive kefir administration decreases the influx of inflammatory cells in the airways and exacerbates the production of mucus and the interleukin 13 cytokine. Additionally, kefir changes macrophage polarisation by decreasing the number of M2 macrophages, as shown by RT-PCR assay. Thus, kefir is a functional food that potentially prevents allergic airway inflammation exacerbations in ovariectomised mice.


Asunto(s)
Asma/prevención & control , Kéfir/microbiología , Probióticos/administración & dosificación , Animales , Asma/genética , Asma/inmunología , Femenino , Fermentación , Humanos , Interleucina-13/genética , Interleucina-13/inmunología , Kéfir/análisis , Lactobacillales/metabolismo , Pulmón/efectos de los fármacos , Pulmón/inmunología , Activación de Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/efectos adversos , Ovalbúmina/inmunología
9.
Benef Microbes ; 12(2): 199-209, 2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33573507

RESUMEN

Allergic contact dermatitis (ACD) is a common allergic skin disease that affects individuals subjected to different antigen exposure conditions and significantly impacts the quality of life of those affected. Numerous studies have demonstrated that probiotics suppress inflammation through immunomodulatory effects. In this study, we aimed to evaluate the effect of the probiotic Bifidobacterium longum 51A as a preventive treatment for ACD using an oxazolone-induced murine model. We demonstrated that B. longum 51A exerted a prophylactic effect on oxazolone-induced ACD-like skin inflammation via reductions in ear and dermal thickness and leucocyte infiltration. The administration of inactivated B. longum 51A did not affect oxazolone-induced ACD-like skin inflammation, suggesting that the bacteria must be alive to be effective. Given that B. longum 51A is an acetate producer, we treated mice with acetate intraperitoneally, which also prevented ear and dermal thickening. Moreover, the tissue levels of the inflammatory cytokines and chemokines interleukin (IL)-10, IL-33, tumour necrosis factor-α, chemokine (C-C motif) ligand 2/monocyte chemoattractant protein-1 and chemokine (C-C motif) ligand 5/RANTES were significantly reduced after probiotic treatment, but only IL-33 and IL-10 were reduced when the mice were treated with acetate. These results show that B. longum 51A exerted a potential prophylactic effect on skin inflammation and that acetate represents one potential mechanism. However, other factors are likely involved since these two treatments do not yield the same results.


Asunto(s)
Bifidobacterium longum/fisiología , Dermatitis Alérgica por Contacto/inmunología , Dermatitis Alérgica por Contacto/prevención & control , Probióticos/administración & dosificación , Animales , Citocinas/genética , Citocinas/inmunología , Dermatitis Alérgica por Contacto/etiología , Dermatitis Alérgica por Contacto/genética , Femenino , Humanos , Interleucina-10/genética , Interleucina-10/inmunología , Interleucina-33/genética , Interleucina-33/inmunología , Ratones , Ratones Endogámicos BALB C , Oxazolona/efectos adversos , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología
10.
Stud Health Technol Inform ; 160(Pt 1): 279-83, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20841693

RESUMEN

Electronic nursing documentation constitutes technical, scientific, legal, and ethical documents. The objective of this study was to develop an electronic nursing documentation system. The system was developed in four phases (conceptualization, detailing, prototype building, implementation), and the knowledge base was based on domains and classes according to the NANDA-I, NIC, and NOC unified framework. The result is an electronic system (PROCEnf--USP--Nursing Process Electronic Documentation System of the University of São Paulo) which allows documenting nursing process generating reports of nursing process, besides supporting decisions on nursing diagnosis, expected outcomes, and interventions. Integration of different fields of knowledge, as well as the institutional feature of valuing continuous theoretical and practical improvement of nursing process were factors of success of this technological project.


Asunto(s)
Sistemas de Información en Laboratorio Clínico/organización & administración , Documentación/métodos , Sistemas de Información en Hospital/organización & administración , Modelos Organizacionales , Diagnóstico de Enfermería/métodos , Diagnóstico de Enfermería/organización & administración , Informática Aplicada a la Enfermería/organización & administración , Brasil , Registros Electrónicos de Salud
11.
Rev Soc Bras Med Trop ; 53: e20200216, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32997052

RESUMEN

INTRODUCTION: The Portuguese man-of-war (Physalia physalis) is a cosmopolitan species, with a widespread distribution and responsible for a great number of injuries caused by cnidarians worldwide, including Brazil. Geoprocessing technology, however, has never been used to assess the spatial distribution of these animals on beaches. The aim of this study was to carry out a health risk assessment of Portuguese man-of-war (P. physalis) envenomations on the São Marcos and Calhau beaches in São Luís city, in the state of Maranhão, Brazil. METHODS: This is a descriptive and quantitative study concerning primary data on the occurrence of the Portuguese man-of-war (P. physalis) and human envenomations in the studied places, conducted over a two-year period in São Luís, Maranhão, northeastern Brazil. RESULTS: Envenomations mainly occurred on beaches presenting high density of P. physalis during the dry period. Vinegar has been incorporated as a first aid, according to recommendations set by the Brazilian Ministry of Health. CONCLUSIONS: In order to improve prevention and control actions of human envenomation, risk areas for this type of envenomation should be clearly indicated as alert areas. Inclusion of the geographical location of the envenomation in the Notification/Investigation SINAN Form was suggested for allowing the continuity of studies involving this public health issue.


Asunto(s)
Mordeduras y Picaduras , Hidrozoos , Animales , Brasil , Humanos , Masculino , Salud Pública , Medición de Riesgo
12.
J Phys Chem B ; 113(4): 989-96, 2009 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-19123834

RESUMEN

The kinetics of the sphere-to-rod transition of micelles composed of triblock copolymers of ethylene oxide and propylene oxide (EO(20)PO(70)EO(20)) have been investigated using dynamic light scattering (DLS) and cryogenic electron transmission microscopy (Cryo-EM). Sphere-to-rod transition is induced by a solvent jump, initiated by adding KCl and ethanol to an aqueous micellar solution. The growth process of the wormlike micelles depends on the experimental conditions and has two distinct regions that can be described as initiation period and actual growth to equilibrium. All growth curves exhibit a single relaxation time that represents the lifetime of the micelles. The growth curves collapse into a master curve, when shifted by the relaxation time, indicating that the actual growth process of the micelles in all samples occurs through the same mechanism. The relaxation time decreases with increasing surfactant concentration. Additionally, some of the formed micelles exhibit a caterpillarlike shape in which some of the original spherical species can still be detected. These facts suggest that the micelles grow longer predominantly by random coagulation/fragmentation reactions involving micellar species of different sizes. However, the appearance of a unimer peak is detected with DLS during the growth stage. This implies that unimer exchange may also contribute to the elongation of the micelles.

13.
J Appl Microbiol ; 107(2): 699-705, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19426276

RESUMEN

AIMS: To purify and partially characterize a bacteriocin produced by a Fusobacterium nucleatum strain. METHODS AND RESULTS: Following protein precipitation the effect of different treatments on a bacteriocin produced by a F. nucleatum strain named P12.2 isolated from a patient with periodontitis was evaluated. The antagonistic activity of the intracellular fraction obtained at 80% ammonium sulphate was preserved at pH values from 6.0 to 9.0 and showed to be sensitive to high temperatures and to treatment with proteases. The fraction was submitted to sequential steps of gel filtration, ion exchange, and reverse phase chromatography, and SDS-PAGE. Data obtained by mass spectrometry revealed that the molecular mass of the protein was 27,296 Da. CONCLUSIONS: For the first time a bacteriocin produced by a F. nucleatum strain was purified and characterized. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first description on characterization of a bacteriocin produced by F. nucleatum. It is possible that the bacteriocin plays a role in the regulation of population levels of periodontopathic organisms.


Asunto(s)
Antibacterianos/aislamiento & purificación , Bacteriocinas/aislamiento & purificación , Fusobacterium nucleatum/metabolismo , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacteriocinas/metabolismo , Bacteriocinas/farmacología , Cromatografía en Gel , Cromatografía de Fase Inversa , Electroforesis en Gel de Poliacrilamida , Calor , Humanos , Concentración de Iones de Hidrógeno , Espectrometría de Masas , Peso Molecular , Boca/microbiología , Periodontitis/microbiología
14.
Toxicon ; 162: 32-39, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30849455

RESUMEN

Lonomia obliqua is a caterpillar of potential therapeutic interest whose venom is able to induce severe blood leakage and modulate leukocyte migration. Since both phenotypes are associated with changes in cytoskeleton dynamics and cell adhesion properties, the aim of this study was to analyze the effects of Lonomia obliqua bristle extract (LOBE) in cell adhesion and migration signaling. Proteomic analysis revealed that epithelial cells (CHO-K1) exposed to LOBE (30 µg/mL, 30 min) exhibited changes in levels of actin regulatory proteins, including RhoGTPases. These changes correlated with an increase in the activity of the RhoGTPase family member Rac as measured by Förster resonance energy transfer (FRET). When plated in migration promoting conditions, CHO-K1 cells exposed to LOBE (10 µg/mL) showed an increase in membrane ruffling after short (30 min) period of incubation that was accompanied by changes in the distribution of the adhesion markers paxillin, vinculin and an increase of focal adhesion kinase autophosphorylation levels (Y397), suggesting changes in cell-extracellular matrix (ECM) adhesion properties and signaling. These data suggest that LOBE possesses bioactive molecules that are capable to modulated cell migration signaling, cytoskeletal dynamics and cell-ECM properties of several cell types.


Asunto(s)
Venenos de Artrópodos/toxicidad , Adhesión Celular/efectos de los fármacos , Mariposas Nocturnas/química , Proteína de Unión al GTP rac1/metabolismo , Actinas/metabolismo , Animales , Células CHO , Movimiento Celular/efectos de los fármacos , Cricetulus , Citoesqueleto/fisiología , Larva/química , Paxillin/metabolismo , Fosforilación , Proteoma/análisis , Vinculina/metabolismo
15.
J Phys Chem B ; 112(3): 793-801, 2008 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-18166031

RESUMEN

The morphological changes of micelles composed of triblock copolymer of ethylene oxide and propylene oxide (EO20PO70EO20) in the presence of different inorganic salts and ethanol have been investigated using dynamic light scattering (DLS), rheometry, and cryogenic transmission electron microscopy (cryo-EM). The following salts were studied: KF, KCl, KI, LiCl, and CsCl. In the presence of KF, KCl, and CsCl, spherical and wormlike micelles coexist. LiCl and KI have little influence on the morphology of the micelles, whereas KF has the most pronounced effect. In agreement with the well-known Hoffmeister anion salt series, F- has the strongest effect of the three anions studied (F-, Cl-, I-). In contrast, the effectiveness of the cation type does not follow the original Hoffmeister cation series. The addition of ethanol to the KCl micellar solutions leads to the formation of more or longer wormlike micelles, which start to interact at certain copolymer concentrations depending on the volume fraction of ethanol added. Both the dilute and the semidilute regimes of the wormlike micelles were studied. The length of the micelles reaches a maximum value at around 8-10 vol % ethanol, after which it decreases again. At higher ethanol concentrations (18 vol %), spherical micelles are formed. Conclusions from this study enhance our understanding of the role played by ethanol and salts in the formation of micelle-templated mesoporous materials, such as SBA-15.

16.
Peptides ; 110: 1-9, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30355532

RESUMEN

Bj-PRO-7a and Bj-PRO-10c belong to a family of proline-rich oligopeptides (PROs) identified in Bothrops jararaca (Bj) crude venom. Previous studies have shown an antihypertensive effect evoked by theses peptides. However, the mechanisms underlying the direct effects on vessels and heart remain to be unraveled. Thus, we investigated the effect of the Bj-PRO-7a and Bj-PRO-10c in the aorta and coronary arteries and in cardiac contractility in normotensive (Wistar) and hypertensive (SHR) rats. Pre-constricted aortic rings were exposed to increasing concentrations of Bj-PROs in presence or absence of muscarinic type 1 receptor antagonist (Pirenzepine), nonselective muscarinic receptor antagonist (Atropine), nitric oxide synthase inhibitor (L-NAME), guanylyl cyclase inhibitor (ODQ), adenylyl cyclase inhibitor (MDL), or argininosuccinate synthetase inhibitor (MDLA). The effects of Bj-PROs in the cardiac contractility and coronary vasomotricity were evaluated using Langendorff perfused heart preparation. The rat hearts were perfused with Bj-PRO-7a or Bj-PRO-10c in absence or presence of L-NAME, ODQ or MDL. Both Bj-PROs induced endothelium-dependent vasorelaxation in aortic rings from Wistars and SHRs. These effects were inhibited by L-NAME, ODQ or MDL. Atropine and Pirenzepine blocked the vasorelaxant effect of Bj-PRO-7a in aorta from both strains. MDLA inhibited the Bj-PRO-10c-induced vasorelaxation in aortic rings from SHR, but not Wistar. The Bj-PRO-7a induced coronary vasodilation only in SHR. L-NAME, ODQ and MDL inhibited this effect. Bj-PRO-10c induced coronary vasodilatation in both strains, which was blocked by L-NAME, ODQ and MDL. Bj-PRO-7a decreased the dP/dt max in Wistar hearts and the dP/dt min in Wistar and SHR hearts. These effects were abolished by L-NAME. Bj-PRO-10c decreased dP/dt max and dP/dt min in hearts from normotensive and hypertensive animals, which were abolished in the presence of L-NAME, MDL and ODQ. In summary, the Bj-PROs induced endothelium-dependent vasorelaxation in rat thoracic aorta, coronary vasodilation and negative inotropic effects through mechanisms mediated by activation of nitric oxide pathway.


Asunto(s)
Antihipertensivos/uso terapéutico , Óxido Nítrico/metabolismo , Receptores Muscarínicos/metabolismo , Vasodilatación/efectos de los fármacos , Inhibidores de Adenilato Ciclasa/uso terapéutico , Animales , Presión Sanguínea/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Masculino , NG-Nitroarginina Metil Éster/farmacología , Ratas , Ratas Wistar , Venenos de Víboras/uso terapéutico
17.
Benef Microbes ; 9(3): 465-476, 2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29633635

RESUMEN

Allergic asthma is a chronic disease mainly characterised by eosinophil inflammation and airway remodelling. Many studies have shown that the gut microbiota of allergic individuals differs from that of non-allergic individuals. Although high levels of bifidobacteria have been associated with healthy persons, Bifidobacterium adolescentis ATCC 15703, a gut bacteria, has been associated with allergic individuals in some clinical studies. The relationship between B. adolescentis ATCC 15703 and asthma or allergies has not been well elucidated, and its effect may be dependent on the host's genetic profile or disease state. To elucidate this question, we evaluated the role of preventive B. adolescentis ATCC 15703 treatment on experimental allergic airway inflammation in two genetically different mouse strains, Balb/c and C57BL/6 (B6). Balb/c mice display a greater predisposition to develop allergic responses than B6 mice. Oral preventive treatment with B. adolescentis ATCC 15703 modulated experimental allergic airway inflammation, specifically in Balb/c mice, which showed decreased levels of eosinophils in the airway. B6 mice did not exhibit any significant alterations in eosinophils but showed an increased influx of total leukocytes and neutrophils into the airway. The mechanism underlying the beneficial effects of these bacteria in experimental allergic mice may involve products of bacteria metabolism, as dead bacteria did not mimic the ability of live B. adolescentis ATCC 15703 to attenuate the influx of eosinophils into the airway. To conclude, preventive oral B. adolescentis ATCC 15703 treatment can attenuate the major characteristic of allergic asthma, eosinophil airway influx, in Balb/c but not B6 mice. These results suggest that oral treatment with this specific live bacterial strain may have therapeutic potential for the treatment of allergic airway disease, although its effect is mouse-strain-dependent.


Asunto(s)
Asma/prevención & control , Bifidobacterium adolescentis/crecimiento & desarrollo , Probióticos/administración & dosificación , Sistema Respiratorio/patología , Administración Oral , Animales , Modelos Animales de Enfermedad , Eosinófilos/inmunología , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Resultado del Tratamiento
18.
Front Microbiol ; 9: 1851, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30150976

RESUMEN

Eutrophication (nutrient over-enrichment) is the primary worldwide water quality issue often leading to nuisance cyanobacterial blooms. Climate change is predicted to cause further rise of cyanobacteria blooms as cyanobacteria can have a competitive advantage at elevated temperatures. We tested the hypothesis that simultaneous rise in nutrients and temperature will promote cyanobacteria more than a single increase in one of the two drivers. To this end, controlled experiments were run with seston from 39 different urban water bodies varying in trophic state from mesotrophic to hypertrophic. These experiments were carried out at two different temperatures, 20°C (ambient) and 25°C (warming scenario) with or without the addition of a surplus of nutrients (eutrophication scenario). To facilitate comparisons, we quantified the effect size of the different treatments, using cyanobacterial and algal chlorophyll a concentrations as a response variable. Cyanobacterial and algal chlorophyll a concentrations were determined with a PHYTO-PAM phytoplankton analyzer. Warming caused an 18% increase in cyanobacterial chlorophyll-a, while algal chlorophyll-a concentrations were on average 8% higher at 25°C than at 20°C. A nutrient pulse had a much stronger effect on chlorophyll-a concentrations than warming. Cyanobacterial chlorophyll-a concentrations in nutrient enriched incubations at 20 or 25°C were similar and 9 times higher than in the incubations without nutrient pulse. Likewise, algal chlorophyll-a concentrations were 6 times higher. The results of this study confirm that warming alone yields marginally higher cyanobacteria chlorophyll-a concentrations, yet that a pulse of additional nutrients is boosting blooms. The responses of seston originating from mesotrophic waters seemed less strong than those from eutrophic waters, which indicates that nutrient control strategies -catchment as well as in-system measures- could increase the resilience of surface waters to the negative effects of climate change.

19.
Braz J Med Biol Res ; 50(4): e5520, 2017 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-28355350

RESUMEN

This study investigated the influence of antihypertensive drugs, such as angiotensin-converting enzyme inhibitors (ACEIs), AT1 receptor blockers (ARBs), voltage-gated L-type calcium channel blockers, and mineralocorticoid receptor antagonists (MRAs), on the effects of angiotensin-(1-7) [Ang-(1-7)] on aorta and coronary arteries from pressure-overloaded rats. Pressure overload was induced by abdominal aortic banding (AB). To evaluate the role of antihypertensive drugs on the effect of Ang-(1-7), AB male Wistar rats weighing 250-300 g were treated with vehicle or low doses (5 mg·kg-1·day-1, gavage) of losartan, captopril, amlodipine, or spironolactone. Isolated aortic rings and isolated perfused hearts under constant flow were used to evaluate the effect of Ang-(1-7) in thoracic aorta and coronary arteries, respectively. Ang-(1-7) induced a significant relaxation in the aorta of sham animals, but this effect was reduced in the aortas of AB rats. Chronic treatments with losartan, captopril or amlodipine, but not with spironolactone, restored the Ang-(1-7)-induced aorta relaxation in AB rats. The coronary vasodilatation evoked by Ang-(1-7) in sham rats was blunted in hypertrophic rats. Only the treatment with losartan restored the coronary vasodilatory effect of Ang-(1-7) in AB rat hearts. These data support a beneficial vascular effect of an association of Ang-(1-7) and some antihypertensive drugs. Thus, this association may have potential as a new therapeutic strategy for cardiovascular diseases.


Asunto(s)
Angiotensina I/farmacología , Antihipertensivos/farmacología , Aorta Abdominal/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Amlodipino/farmacología , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Bloqueadores de los Canales de Calcio/farmacología , Captopril/farmacología , Losartán/farmacología , Masculino , Antagonistas de Receptores de Mineralocorticoides/farmacología , Modelos Animales , Ratas Wistar , Reproducibilidad de los Resultados , Espironolactona/farmacología , Factores de Tiempo , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacos
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