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1.
Plant Biol (Stuttg) ; 26(4): 647-661, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38488200

ABSTRACT

To investigate how and to what extent there are differences in the photosynthetic plasticity of trees in response to different light environments, six species from three successional groups (late successional, mid-successional, and pioneers) were exposed to three different light environments [deep shade - DS (5% full sunlight - FS), moderate shade - MS (35% FS) and full sunlight - FS]. Maximum net photosynthesis (Amax), leaf N partitioning, stomatal, mesophile, and biochemical limitations (SL, ML, and BL, respectively), carboxylation velocity (Vcmax), and electron transport (Jmax) rates, and the state of photosynthetic induction (IS) were evaluated. Higher values of Amax, Vcmax, and Jmax in FS were observed for pioneer species, which invested the largest amount of leaf N in Rubisco. The lower IS for pioneer species reveals its reduced ability to take advantage of sunflecks. In general, the main photosynthetic limitations are diffusive, with SL and ML having equal importance under FS, and ML decreasing along with irradiance. The leaf traits, which are more determinant of the photosynthetic process, respond independently in relation to the successional group, especially with low light availability. An effective partitioning of leaf N between photosynthetic and structural components played a crucial role in the acclimation process and determined the increase or decrease of photosynthesis in response to the light conditions.


Subject(s)
Photosynthesis , Plant Leaves , Sunlight , Trees , Photosynthesis/physiology , Trees/physiology , Plant Leaves/physiology , Plant Leaves/radiation effects , Plant Leaves/metabolism , Light , Brazil , Acclimatization/physiology , Electron Transport , Ribulose-Bisphosphate Carboxylase/metabolism , Nitrogen/metabolism
2.
Braz J Biol ; 83: e273777, 2023.
Article in English | MEDLINE | ID: mdl-37970900

ABSTRACT

The cowpea bean [Vigna unguiculata (L.) Walp.], a legume of great socioeconomic importance, it was previously cultivated exclusively for subsistence and commercial purposes, especially in the North and Northeast regions. This crop has a low production cost and high nutritional value, in addition to a high potential for productivity growth and expansion to other regions. The objective of this work was to evaluate parameters of growth and production in cowpea culture, as a function of potassium fertilization in soil of the cerrado of Amapá. The parameters of growth and production of the cowpea culture were evaluated, as a function of potassium fertilization in the soil of the cerrado of Amapá. The experiment was conducted in a greenhouse, using a completely randomized experimental design, with four replications, in a 5x2 factorial scheme, totaling 40 experimental units, which were composed of plastic pots containing 7 dm3 of soil collected from the arable layer (0-20 cm ) of a typical Hyperdystrophic Yellow Argisol, with a sandy clay loam texture, in a cerrado area in the municipality of Porto Grande-AP. The factors consisted of the control treatment (without K), four doses of K (45, 90, 135 and 180 kg ha-1) in the form of potassium chloride, and two cowpea cultivars (Pretinho and BRS Tumucumaque). The cultivar BRS Tumucumaque shows better growth and production of cowpea plants. Doses of 90 kg ha-1 provided greater height (98.75 cm) and stem diameter (10.0 mm). As for production, the dose of 135 kg ha-1 caused greater grain weight gain (5.25 g) and dry mass of pods (13.92 g), and the doses of 90 and 180 kg ha-1 induced greater number and length of pods (3.16 pods) respectively. These results show better responsiveness of the BRS Tumucumaque cultivar at doses of 90, 135 and 180 kg ha-1 in the type of soil where the study was conducted.


Subject(s)
Fabaceae , Vigna , Soil , Potassium , Brazil
3.
Nat Commun ; 14(1): 3804, 2023 06 26.
Article in English | MEDLINE | ID: mdl-37365163

ABSTRACT

The interleukin-1 family members, IL-1ß and IL-18, are processed into their biologically active forms by multi-protein complexes, known as inflammasomes. Although the inflammasome pathways that mediate IL-1ß processing in myeloid cells have been defined, those involved in IL-18 processing, particularly in non-myeloid cells, are still not well understood. Here we report that the host defence molecule NOD1 regulates IL-18 processing in mouse epithelial cells in response to the mucosal pathogen, Helicobacter pylori. Specifically, NOD1 in epithelial cells mediates IL-18 processing and maturation via interactions with caspase-1, instead of the canonical inflammasome pathway involving RIPK2, NF-κB, NLRP3 and ASC. NOD1 activation and IL-18 then help maintain epithelial homoeostasis to mediate protection against pre-neoplastic changes induced by gastric H. pylori infection in vivo. Our findings thus demonstrate a function for NOD1 in epithelial cell production of bioactive IL-18 and protection against H. pylori-induced pathology.


Subject(s)
Epithelial Cells , Helicobacter Infections , Interleukin-18 , Nod1 Signaling Adaptor Protein , Animals , Mice , Epithelial Cells/metabolism , Helicobacter Infections/metabolism , Helicobacter pylori , Inflammasomes/metabolism , Interleukin-18/metabolism , Interleukin-1beta/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Signal Transduction , Nod1 Signaling Adaptor Protein/metabolism
5.
J Frailty Aging ; 10(4): 337-342, 2021.
Article in English | MEDLINE | ID: mdl-34549248

ABSTRACT

The purpose of this study was to characterize Cognitive Motor Dual Task (CMDT) costs for a community-based sample of older adults with Motoric Cognitive Risk Syndrome (MCR), as well as investigate associations between CMDT costs and cognitive performance. Twenty-five community-dwelling older adults (ages 60-89 years) with MCR performed single and dual task complex walking scenarios, as well as a computerized cognitive testing battery. Participants with lower CMDT costs had higher scores on composite measures of Working Memory, Processing Speed, and Shifting, as well as an overall cognitive composite measure. In addition, participants with faster single task gait velocity had higher scores on composite measures of Working Memory, Processing Speed, and overall cognition. Taken together, these results suggest that CMDT paradigms can help to elucidate the interplay between cognitive and motor abilities for older adults with MCR.


Subject(s)
Cognition , Walking , Aged , Aged, 80 and over , Gait , Humans , Independent Living , Neuropsychological Tests
6.
JAR Life ; 9: 47-54, 2020.
Article in English | MEDLINE | ID: mdl-36034540

ABSTRACT

Background: Modifiable lifestyle factors such as diet are associated with cognitive decline and dementia. Greater understanding of the nutritional intake of older adults who are at increased risk for cognitive decline may allow for the development of more effective dietary interventions to prevent or delay the onset of dementia. Objectives: The purpose of this study was to characterize the nutritional status, diet quality and individual nutritional components of older adults with motoric cognitive risk syndrome (MCR). MCR is a pre-dementia syndrome classified by slow gait speed and subjective memory impairments. Design: Cross-sectional analysis. Setting: A community-based senior center located in an urban setting. Participants: Twenty-five community-dwelling older adults with MCR aged 60-89 yrs. Measurements: Nutritional risk status was determined using the Nestle Mini Nutritional Assessment (MNA). A food frequency questionnaire was used to quantify: overall dietary quality using the Healthy Eating Index (HEI); adherence to the Mediterranean-DASH for Neurodegenerative Delay (MIND) dietary pattern; and intake of individual nutritional components shown to be protective or harmful for cognitive function in older adults. Participants completed a computerized cognitive testing battery to assess cognitive abilities. Results: More than one third (36%) of participants were at increased risk for malnutrition. Participants at lower risk for malnutrition had better working memory (r = 0.40, p = 0.04), executive functioning (r = 0.44, p = 0.03), and overall cognition (r = 0.44, p = 0.03). While participants generally consumed a reasonable quality diet (HEI = 65.15), 48% of participants had poor adherence to a neuroprotective MIND dietary pattern. Higher intake of B-complex vitamins was associated with better task switching (r = 0.40, p ≤ 0.05) and faster processing speeds (r = 0.39, p ≤ 0.05). Higher vitamin C intake was associated with better executive functioning (r = 0.40, p ≤ 0.05). Conclusions: Our findings suggest that a significant proportion of older adults with MCR may be at increased risk for malnutrition. While the diet quality of older adults with MCR appeared to need improvement, future studies should investigate the effects of more specific nutritional interventions, including the MIND diet, on cognition in at-risk older adults.

7.
8.
Int Endod J ; 52(2): 139-148, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30040127

ABSTRACT

AIM: To compare the impact of the two different root canal preparation systems on the quality of life of patients and correlate postoperative pain with the impact on quality of life. METHODOLOGY: A randomized clinical trial was conducted with 58 patients allocated into two groups based on the root canal preparation system employed: ProTaper Next (PN) or Reciproc (R). Data collection involved the administration of a questionnaire addressing demographic and clinical characteristics, the OHIP-14 (quality of life) and a visual analog scale (pain). The latter two were the outcomes of interest and were administered in the first 24 h after root canal treatment. The data were submitted to descriptive analysis, bivariate analysis, Poisson univariate and multiple regression, and Spearman's correlation test, with a 5% significance level. RESULTS: A greater frequency of impact after treatment was found for the items 'uncomfortable to eat food' and 'felt self-conscious'. No significant difference between groups was found regarding the severity of impact for total OHIP-14 score or any of the domain scores. CONCLUSIONS: The two root canal preparation systems exerted a similar impact on quality of life. Postoperative pain was correlated with impact on quality of life, affecting chewing function, self-consciousness and stress. Thus, it is important for dentists to provide care capable of preventing or treating the negative consequences of such therapy.


Subject(s)
Quality of Life/psychology , Root Canal Preparation/instrumentation , Root Canal Preparation/methods , Root Canal Therapy/instrumentation , Root Canal Therapy/methods , Adolescent , Adult , Aged , Consciousness , Dentists , Double-Blind Method , Endodontics , Humans , Male , Mastication , Middle Aged , Pain Measurement , Pain, Postoperative/prevention & control , Risk Factors , Stress, Psychological/prevention & control , Surveys and Questionnaires , Young Adult
9.
Braz J Med Biol Res ; 51(11): e7169, 2018 Oct 08.
Article in English | MEDLINE | ID: mdl-30304094

ABSTRACT

Neonatal asphyxia occurs due to reduction in oxygen supply to vital organs in the newborn. Rapid restoration of oxygen to the lungs after a long period of asphyxia can cause lung injury and decline of respiratory function, which result from the activity of molecules that induce vascular changes in the lung such as nitric oxide (NO) and vascular endothelial growth factors (VEGF). In this study, we evaluated the pulmonary and vascular morphometry of rats submitted to the model of neonatal asphyxia and mechanical ventilation, their expression of pulmonary VEGF, VEGF receptors (VEGFR-1/VEGFR-2), and endothelial NO synthase (eNOS). Neonate Sprague-Dawley rats (CEUA #043/2011) were divided into four groups (n=8 each): control (C), control submitted to ventilation (CV), hypoxia (H), and hypoxia submitted to ventilation (HV). The fetuses were harvested at 21.5 days of gestation. The morphometric variables measured were body weight (BW), total lung weight (TLW), left lung weight (LLW), and TLW/BW ratio. Pulmonary vascular measurements, VEGFR-1, VEGFR-2, VEGF, and eNOS immunohistochemistry were performed. The morphometric analysis showed decreased TLW and TLW/BW ratio in HV compared to C and H (P<0.005). Immunohistochemistry showed increased VEGFR-2/VEGF and decreased VEGFR-1 expression in H (P<0.05) and lower eNOS expression in H and HV. Median wall thickness was increased in H, and the expression of VEGFR-1, VEGFR-2, VEGF, and eNOS was altered, especially in neonates undergoing H and HV. These data suggested the occurrence of arteriolar wall changes mediated by NO and VEGF signaling in neonatal hypoxia.


Subject(s)
Asphyxia Neonatorum/therapy , Lung/pathology , Nitric Oxide Synthase Type III/analysis , Respiration, Artificial/adverse effects , Vascular Endothelial Growth Factor A/analysis , Vascular Endothelial Growth Factor Receptor-1/analysis , Vascular Endothelial Growth Factor Receptor-2/analysis , Animals , Arterioles/pathology , Asphyxia Neonatorum/pathology , Asphyxia Neonatorum/physiopathology , Disease Models, Animal , Immunohistochemistry , Lung/blood supply , Lung/physiopathology , Rats, Sprague-Dawley , Reference Values , Respiration, Artificial/methods
10.
Braz. j. med. biol. res ; 51(11): e7169, 2018. tab, graf
Article in English | LILACS | ID: biblio-951729

ABSTRACT

Neonatal asphyxia occurs due to reduction in oxygen supply to vital organs in the newborn. Rapid restoration of oxygen to the lungs after a long period of asphyxia can cause lung injury and decline of respiratory function, which result from the activity of molecules that induce vascular changes in the lung such as nitric oxide (NO) and vascular endothelial growth factors (VEGF). In this study, we evaluated the pulmonary and vascular morphometry of rats submitted to the model of neonatal asphyxia and mechanical ventilation, their expression of pulmonary VEGF, VEGF receptors (VEGFR-1/VEGFR-2), and endothelial NO synthase (eNOS). Neonate Sprague-Dawley rats (CEUA #043/2011) were divided into four groups (n=8 each): control (C), control submitted to ventilation (CV), hypoxia (H), and hypoxia submitted to ventilation (HV). The fetuses were harvested at 21.5 days of gestation. The morphometric variables measured were body weight (BW), total lung weight (TLW), left lung weight (LLW), and TLW/BW ratio. Pulmonary vascular measurements, VEGFR-1, VEGFR-2, VEGF, and eNOS immunohistochemistry were performed. The morphometric analysis showed decreased TLW and TLW/BW ratio in HV compared to C and H (P<0.005). Immunohistochemistry showed increased VEGFR-2/VEGF and decreased VEGFR-1 expression in H (P<0.05) and lower eNOS expression in H and HV. Median wall thickness was increased in H, and the expression of VEGFR-1, VEGFR-2, VEGF, and eNOS was altered, especially in neonates undergoing H and HV. These data suggested the occurrence of arteriolar wall changes mediated by NO and VEGF signaling in neonatal hypoxia.


Subject(s)
Animals , Asphyxia Neonatorum/therapy , Respiration, Artificial/adverse effects , Vascular Endothelial Growth Factor Receptor-1/analysis , Vascular Endothelial Growth Factor Receptor-2/analysis , Vascular Endothelial Growth Factor A/analysis , Nitric Oxide Synthase Type III/analysis , Lung/pathology , Arterioles/pathology , Reference Values , Asphyxia Neonatorum/physiopathology , Asphyxia Neonatorum/pathology , Respiration, Artificial/methods , Immunohistochemistry , Rats, Sprague-Dawley , Disease Models, Animal , Lung/physiopathology , Lung/blood supply
11.
Arq. bras. med. vet. zootec. (Online) ; 69(4): 1054-1061, jul.-ago. 2017. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-876945

ABSTRACT

Neste trabalho, foi avaliada a prevalência das principais causas de condenação de fígado bovino em abatedouro frigorífico sob Serviço de Inspeção Federal, situado na Zona da Mata mineira. Para obtenção dos dados, foram consultadas fichas relativas ao movimento mensal de abate de bovinos e de causas de condenação, no período compreendido entre 2007 e 2013, no referido estabelecimento. Durante esse período, foram abatidos 150.752 bovinos, e a prevalência de condenação hepática entre os anos variou de 9,38% a 14,09%. As principais patologias envolvidas foram abscesso, telangiectasia e fasciolose, responsáveis por 32,03%, 29,20% e 21,95% das condenações, respectivamente. Além disso, foi observada tendência de redução na frequência de condenação por abscesso (3,26%) e telangiectasia (0,68%) ao ano e, em contraposição, aumento por fasciolose de 3,40% ao ano. Conclui-se que as patologias responsáveis pelas condenações de fígado bovino foram abscesso, telangiectasia e fasciolose e que a inspeção post mortem tem grande importância no monitoramento da saúde e da produção animal e na qualidade da carne a ser comercializada.(AU)


The aim of the present study was to evaluate the frequency of the main causes for condemnation of bovine liver in an abattoir/cold store under the Federal Inspection Services, located in the Zona da Mata of the state of Minas Gerais, between 2007 and 2013. Study data was collated from forms containing information about the number of cattle slaughtered per month and the causes for liver condemnation at the studied abattoir. During the period under study, 150,752 cattle were slaughtered, and the frequency of liver condemnation varied between 9.38% and 14.09% from year to year. The main pathologies that led to liver condemnation were abscesses, telangiectasis, and fasciolosis, which were responsible for 32.03%, 29.20%, and 21.95% of the condemnations, respectively. The frequency of condemnation because of abscesses and telangiectasis showed a trend of decline, 3.26% and 0.68% per year, respectively. The frequency of condemnation because of fasciolosis, however, showed a trend of increase by 3.40% per year. This study shows the usefulness of post mortem inspection of animal health and production monitoring.(AU)


Subject(s)
Animals , Food Inspection , Liver/microbiology , Meat/analysis , Cattle , Fascioliasis/veterinary , Liver Abscess/veterinary , Telangiectasis/veterinary
12.
Colloids Surf B Biointerfaces ; 157: 335-346, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28618356

ABSTRACT

Although graphene oxide (GO), a nanomaterial with hexagonal planar layer, has been widely studied due to its applications in neurobiology that include drug delivery and tissue engineering, additional studies to assess its potential toxic effects are still needed. Thus, this study evaluated the effects of GO exposure (at 5, 10, 50 or 100mg/L) during six consecutive days on mortality, hatching, spontaneous movement, heart rate, morphology, locomotion behavior, acetylcholinesterase (AChE) activity, dopamine levels and relative gene expression of developmental neurology-related genes using zebrafish larvae. In the 5mg/L dose, synapsin IIa expression up-regulation was seen concomitantly with down-regulation of dat expression, showing a potential compensatory mechanism. Moreover, the 10mg/L exposure caused an increase in heart rate, in absolute turn angle, brain cell damage and a decrease in dopamine levels. These alterations may be associated with autophagosome formation found in GO-exposed larval brain. No changes were observed on higher doses of GO exposure, probably due to nanomaterial agglomeration. Taken together, these results show that toxic effects of GO exposure are not dose-dependent, and are preeminent in lower concentrations. Additional studies are needed to deepen the specific mechanisms of GO neurotoxicity and are required to elucidate its potential biomedical use.


Subject(s)
Graphite/chemistry , Graphite/pharmacology , Larva/drug effects , Oxides/chemistry , Oxides/pharmacology , Animals , Autophagosomes/drug effects , Nanotechnology , Zebrafish
13.
Arq. bras. med. vet. zootec ; 69(2): 333-339, mar.-abr. 2017. ilus
Article in English | LILACS, VETINDEX | ID: biblio-833826

ABSTRACT

Pneumocephalus is defined as the presence of air in any of the intracranial compartments. Its most frequent causes are trauma and cranial surgery. Clinical signs occur as a result of increased intracranial pressure and vary with the location and extent of the lesion. A case involving a seven-month-old female Saint Bernard, who suffered cranial trauma caused by a bite to the face at ten days of age and had presented with seizures and localized pain four months previously is reported. A computed tomography scan of the skull revealed a nasocephalic mass with low contrast enhancement, bone lysis, and hypodensity (-940 Hounsfield units) of the lateral and third ventricles, indicating intraventricular pneumocephalus. During surgery, a fragment of the mass was collected for histopathological examination, which demonstrated the presence of multifocal areas of necrosis. The computed tomography (CT) is a reliable method for the characterization of intracranial lesions and diagnosis of pneumocephalus, whose occurrence must be considered in pathological processes in which there is increased intracranial pressure and in patients undergoing certain surgical procedures and anesthetic specific, and CT is indicated as a monitoring tool for these patients.(AU)


Pneumoencéfalo é definido como a presença de gás em quaisquer dos compartimentos intracranianos e possui como causas mais frequentes o traumatismo e cirurgias cranianas. Os sinais clínicos ocorrem como consequência do aumento de pressão intracraniana e variam conforme o local e a extensão da lesão. Relata-se o caso de uma cadela de sete meses de idade, da raça São Bernardo, que sofreu trauma por mordedura em face, quatro meses antes, apresentando crises convulsivas e sensibilidade dolorosa local desde então. O exame tomográfico do crânio revelou massa nasoencefálica com baixa captação de contraste, lise óssea e hipodensidade (-940HU) dos ventrículos laterais e terceiro ventrículo encefálico, caracterizando pneumoencéfalo intraventricular. Foi realizada intervenção cirúrgica e coleta de fragmento da massa para exame histopatológico, que demonstrou existência de necrose multifocal. O exame de tomografia computadorizada (TC) é um método confiável para a caracterização de lesões intracranianas e diagnóstico de pneumoencéfalo, cuja ocorrência deve ser considerada em processos patológicos nos quais há aumento da pressão intracraniana e em pacientes submetidos a alguns procedimentos cirúrgicos e anestésicos específicos, sendo a TC indicada como ferramenta de monitoramento desses pacientes.(AU)


Subject(s)
Animals , Dogs , Brain/surgery , Craniocerebral Trauma/diagnosis , Craniocerebral Trauma/veterinary , Necrosis , Tomography, X-Ray Computed/veterinary
14.
Arq. bras. med. vet. zootec. (Online) ; 69(2): l3393-339, mar.-abr. 2017. ilus
Article in English | LILACS, VETINDEX | ID: biblio-1462529

ABSTRACT

Pneumocephalus is defined as the presence of air in any of the intracranial compartments. Its most frequent causes are trauma and cranial surgery. Clinical signs occur as a result of increased intracranial pressure and vary with the location and extent of the lesion. A case involving a seven-month-old female Saint Bernard, who suffered cranial trauma caused by a bite to the face at ten days of age and had presented with seizures and localized pain four months previously is reported. A computed tomography scan of the skull revealed a nasocephalic mass with low contrast enhancement, bone lysis, and hypodensity (-940 Hounsfield units) of the lateral and third ventricles, indicating intraventricular pneumocephalus. During surgery, a fragment of the mass was collected for histopathological examination, which demonstrated the presence of multifocal areas of necrosis. The computed tomography (CT) is a reliable method for the characterization of intracranial lesions and diagnosis of pneumocephalus, whose occurrence must be considered in pathological processes in which there is increased intracranial pressure and in patients undergoing certain surgical procedures and anesthetic specific, and CT is indicated as a monitoring tool for these patients.


Pneumoencéfalo é definido como a presença de gás em quaisquer dos compartimentos intracranianos e possui como causas mais frequentes o traumatismo e cirurgias cranianas. Os sinais clínicos ocorrem como consequência do aumento de pressão intracraniana e variam conforme o local e a extensão da lesão. Relata-se o caso de uma cadela de sete meses de idade, da raça São Bernardo, que sofreu trauma por mordedura em face, quatro meses antes, apresentando crises convulsivas e sensibilidade dolorosa local desde então. O exame tomográfico do crânio revelou massa nasoencefálica com baixa captação de contraste, lise óssea e hipodensidade (-940HU) dos ventrículos laterais e terceiro ventrículo encefálico, caracterizando pneumoencéfalo intraventricular. Foi realizada intervenção cirúrgica e coleta de fragmento da massa para exame histopatológico, que demonstrou existência de necrose multifocal. O exame de tomografia computadorizada (TC) é um método confiável para a caracterização de lesões intracranianas e diagnóstico de pneumoencéfalo, cuja ocorrência deve ser considerada em processos patológicos nos quais há aumento da pressão intracraniana e em pacientes submetidos a alguns procedimentos cirúrgicos e anestésicos específicos, sendo a TC indicada como ferramenta de monitoramento desses pacientes.


Subject(s)
Animals , Dogs , Brain/surgery , Necrosis , Craniocerebral Trauma/diagnosis , Craniocerebral Trauma/veterinary , Tomography, X-Ray Computed/veterinary
15.
Exp Parasitol ; 172: 51-60, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28011169

ABSTRACT

Leishmaniasis is caused by protozoan parasites belonging to the genus Leishmania and includes cutaneous, mucocutaneous and visceral clinical forms. The drugs currently available for leishmaniasis treatment are pentavalent antimonials, amphotericin B and miltefosine, which present high toxicity, elevated cost and development of parasite resistance. The natural products constitute an important source of substances with leishmanicidal potential. Here we evaluated in vitro the anti-Leishmania amazonensis activity of crude extracts of branches, leaves and fruits of Guatteria latifolia. The branch extract (GCE) exhibited promising leishmanicidal activity against promastigotes (IC50 51.7 µg/ml), and was submitted to fractionation guided by in vitro assays. Among the seven subfractions obtained, GF1 and GF2 were the most actives against promastigotes with IC50 25.6 and 16 µg/ml, respectively. Since GCE, GF1 and GF2 were not toxic for macrophages, next, we tested their effect on intracellular amastigotes, and the IC50 values obtained were, respectively 30.5, 10.4 and 7.4 µg/ml, after 24 h treatment. The selectivity index for GCE, GF1 and GF2 were >6.5, >19.2 and > 27, respectively. Additionally, GCE, GF1 and GF2 affected the division pattern of the promastigotes by increasing 6.7, 9.4 and 7-fold the cells in Sub-G0/G1 phase, and decreasing 1.6, 2.5 and 1.8-fold the cells in G0/G1 phase, respectively. To assess the GCE and GFs capacity to modulate microbicidal mechanisms of macrophages, nitric oxide (NO) and TNF-α production were tested. Our results indicated that at the IC50s GCE, GF1 and GF2 decreased NO production of infected macrophages stimulated with IFN-γ and LPS, besides, only GF1 decreased the production of TNF-α. Our data warrant further studies of GCE, GF1 and GF2 to identify active compounds against Leishmania parasites.


Subject(s)
Alkaloids/pharmacology , Antiprotozoal Agents/pharmacology , Guatteria , Leishmania mexicana/drug effects , Plant Extracts/pharmacology , Alkaloids/analysis , Alkaloids/isolation & purification , Antiprotozoal Agents/chemistry , Antiprotozoal Agents/isolation & purification , Cell Cycle/drug effects , Interferon-gamma/biosynthesis , Leishmania mexicana/cytology , Leishmania mexicana/metabolism , Macrophage Activation , Macrophages/immunology , Macrophages/parasitology , Mitochondria/drug effects , Mitochondria/metabolism , Nitric Oxide/metabolism , Plant Extracts/chemistry , Tumor Necrosis Factor-alpha/biosynthesis
16.
Mater Sci Eng C Mater Biol Appl ; 64: 370-375, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-27127066

ABSTRACT

Composites of biodegradable polymers and calcium phosphate are bioactive and flexible, and have been proposed for use in tissue engineering and bone regeneration. When associated with the broad-spectrum antibiotic doxycycline (DOX), they could favor antimicrobial action and enhance the action of osteogenic composites. Composites of polycaprolactone (PCL), poly(lactic-co-glycolic acid) (PLGA), and a bioceramic of biphasic calcium phosphate Osteosynt® (BCP) were loaded with DOX encapsulated in ß-cyclodextrin (ßCD) and were evaluated for effects on osteoblastic cell cultures. The DOX/ßCD composite was prepared with a double mixing method. Osteoblast viability was assessed with methyl tetrazolium (MTT) assays after 1day, 7day, and 14days of composite exposure; alkaline phosphatase (AP) activity and collagen production were evaluated after 7days and 14days, and mineral nodule formation after 14days. Composite structures were evaluated by scanning electron microscopy (SEM). Osteoblasts exposed to the composite containing 25µg/mL DOX/ßCD had increased cell proliferation (p<0.05) compared to control osteoblast cultures at all experimental time points, reaching a maximum in the second week. AP activity and collagen secretion levels were also elevated in osteoblasts exposed to the DOX/ßCD composite (p<0.05 vs. controls) and reached a maximum after 14days. These results were corroborated by Von Kossa test results, which showed strong formation of mineralization nodules during the same time period. SEM of the composite material revealed a surface topography with pore sizes suitable for growing osteoblasts. Together, these results suggest that osteoblasts are viable, proliferative, and osteogenic in the presence of a DOX/ßCD-containing BCP ceramic composite.


Subject(s)
Calcium Phosphates , Cyclodextrins , Doxycycline , Drug Carriers , Lactic Acid , Osteoblasts/metabolism , Osteogenesis/drug effects , Polyesters , Polyglycolic Acid , Animals , Calcium Phosphates/chemistry , Calcium Phosphates/pharmacokinetics , Calcium Phosphates/pharmacology , Cells, Cultured , Cyclodextrins/chemistry , Cyclodextrins/pharmacokinetics , Cyclodextrins/pharmacology , Doxycycline/chemistry , Doxycycline/pharmacokinetics , Doxycycline/pharmacology , Drug Carriers/chemistry , Drug Carriers/pharmacokinetics , Drug Carriers/pharmacology , Lactic Acid/chemistry , Lactic Acid/pharmacokinetics , Lactic Acid/pharmacology , Male , Osteoblasts/cytology , Polyesters/chemistry , Polyesters/pharmacokinetics , Polyesters/pharmacology , Polyglycolic Acid/chemistry , Polyglycolic Acid/pharmacokinetics , Polyglycolic Acid/pharmacology , Polylactic Acid-Polyglycolic Acid Copolymer , Rats , Rats, Wistar
17.
Nature ; 529(7587): 519-22, 2016 Jan 28.
Article in English | MEDLINE | ID: mdl-26819045

ABSTRACT

The equatorial Pacific Ocean is one of the major high-nutrient, low-chlorophyll regions in the global ocean. In such regions, the consumption of the available macro-nutrients such as nitrate and phosphate is thought to be limited in part by the low abundance of the critical micro-nutrient iron. Greater atmospheric dust deposition could have fertilized the equatorial Pacific with iron during the last ice age--the Last Glacial Period (LGP)--but the effect of increased ice-age dust fluxes on primary productivity in the equatorial Pacific remains uncertain. Here we present meridional transects of dust (derived from the (232)Th proxy), phytoplankton productivity (using opal, (231)Pa/(230)Th and excess Ba), and the degree of nitrate consumption (using foraminifera-bound δ(15)N) from six cores in the central equatorial Pacific for the Holocene (0-10,000 years ago) and the LGP (17,000-27,000 years ago). We find that, although dust deposition in the central equatorial Pacific was two to three times greater in the LGP than in the Holocene, productivity was the same or lower, and the degree of nitrate consumption was the same. These biogeochemical findings suggest that the relatively greater ice-age dust fluxes were not large enough to provide substantial iron fertilization to the central equatorial Pacific. This may have been because the absolute rate of dust deposition in the LGP (although greater than the Holocene rate) was very low. The lower productivity coupled with unchanged nitrate consumption suggests that the subsurface major nutrient concentrations were lower in the central equatorial Pacific during the LGP. As these nutrients are today dominantly sourced from the Subantarctic Zone of the Southern Ocean, we propose that the central equatorial Pacific data are consistent with more nutrient consumption in the Subantarctic Zone, possibly owing to iron fertilization as a result of higher absolute dust fluxes in this region. Thus, ice-age iron fertilization in the Subantarctic Zone would have ultimately worked to lower, not raise, equatorial Pacific productivity.


Subject(s)
Ice Cover , Iron/analysis , Iron/chemistry , Seawater/chemistry , Atmosphere/chemistry , Dust/analysis , Foraminifera/metabolism , History, Ancient , Nitrates/metabolism , Pacific Ocean , Phytoplankton/metabolism
18.
Allergy ; 70(8): 985-94, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25939706

ABSTRACT

BACKGROUND: Neonatal vitamin A supplementation (NVAS) is currently being considered as policy in countries at risk of deficiency. A previous study suggested that NVAS may be associated with increased atopy. We examined the effect of NVAS on atopy by conducting long-term follow-up of a previous randomized controlled trial in Guinea-Bissau. METHODS: In 2002-2004, we randomized 4345 normal birthweight neonates to NVAS (50 000 IU retinyl palmitate) or placebo together with their Bacillus Calmette-Guérin vaccination. In 2013, we visited the 1692 (39%) children now aged 8-10 years who were still living in the study area, and 1478 (87%) were found at home. Provided consent, a skin prick test was performed, and history of allergic symptoms was recorded. Associations of NVAS and atopy (defined as skin prick test reaction of ≥3 mm) were analysed using binomial regression. RESULTS: Of the 1430 children with a valid skin prick test, 228 (16%) were positive (more boys (20%) than girls (12%), P-value < 0.0001). NVAS did not increase the overall risk of atopy (RR 1.10 [95% CI 0.87-1.40]). However, NVAS was associated with significantly increased risk among females (RR 1.78 [1.17-2.72]) but not among males (0.86 [0.64-1.15], P-value for interaction between NVAS and gender = 0.005). Furthermore, NVAS was associated with increased risk of wheezing among females (RR 1.80 [1.03-3.17], but not among males, P-value for interaction = 0.05). CONCLUSION: The study corroborated previous observations; NVAS was associated with increased risk of atopy and wheezing, in this study only among females. Further studies on NVAS and atopy are warranted.


Subject(s)
Dietary Supplements/adverse effects , Hypersensitivity, Immediate/epidemiology , Hypersensitivity, Immediate/etiology , Vitamin A/administration & dosage , Vitamin A/adverse effects , Age Distribution , BCG Vaccine/administration & dosage , Child , Developing Countries , Female , Follow-Up Studies , Guinea-Bissau , Humans , Incidence , Infant, Newborn , Male , Risk Assessment , Sex Distribution , Skin Tests/methods , Vaccination/methods
19.
Rev. bras. plantas med ; 17(4,supl.2): 865-874, 2015. tab, graf
Article in English | LILACS | ID: lil-771170

ABSTRACT

ABSTRACT The extracts and fractions of leaves and branches of Protium hebetatum D. C. Daly (Burseraceae) were investigated for their antibacterial activity and chemical composition. The methanol extract of branches (EMG) was considered active against the Escherichia coli and the Proteus vulgaris, showing an inhibition zone of 13 mm, and was selected for bioassay-guided phytochemical fractionation. From the technique of broth microdilution, the extract was considered a moderate inhibitor against Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis, with a minimum inhibitory concentration (MIC) of 1 mg/mL. The dichloromethane fraction was considered a moderate inhibitor against S. aureus (MIC of 1 mg/mL) and a potent inhibitor against E. faecalis (MIC of 0.5 mg/mL). F1, F2, F5 and F6 from chromatographic column of dichloromethane fraction were considered moderate inhibitors against S. aureus (MIC of 1 mg/mL). Through analysis by a gas chromatography mass spectrometry, eighteen compounds were identified, from which thirteen (isoeugenol, p-vinylguaiacol, metoxyeugenol, coumarin, 5-hydroxy-scopoletin, 4,7-dihydroxy-6-metoxicromam-2-one, 4[(1E]-3-hydroxy-1-propenyl)-2-methoxyphenol, piperonal, scoparon, o-guaiacol, spathulenol, seringol and antiarol) are unprecedented in these species. We also identified the triterpenes α-amyrin and β-amyrin, the steroids stigmasterol and sitosterol and the coumarin scopoletin, which was closely linked to the antibacterial activity of the samples.


RESUMO Atividade antibacteriana e compostos químicos de folhas e galhos de Protium hebetatum. Extratos e frações de folhas e galhos de Protium hebetatum D. C. Daly (Burseraceae) foram investigados quanto sua atividade antibacteriana e composição química. O extrato metanólico dos galhos (EMG) foi considerado ativo contra Escherichia coli e Proteus vulgaris, apresentando um halo de inibição de 13 mm, sendo selecionado para um fracionamento fitoquímico biomonitorado. A partir da técnica de microdiluição em caldo o EMG foi considerado um inibidor moderado contra Staphylococcus aureus, Pseudomonas aeruginosa e Enterococcus faecalis, apresentando uma concentração inibitória mínima (CIM) de 1mg/mL. A fração diclorometânica foi considerada inibidora moderada contra S. aureus (CIM de 1 mg/mL) e inibidora potente contra E. faecalis (CIM de 0,5 mg/mL). F1, F2, F5 e F6 provenientes da fração diclorometânica foram consideradas inibidoras moderadas contra S. aureus (CIM de 1 mg/mL). Através da análise por cromatografia gasosa acoplada a espectrometria de massa, foram identificados dezoitos compostos, dos quais treze (isoeugenol, p-vinilguaiacol, metoxieugenol, cumarina, 5-hidroxi-escopoletina, 4,7-dihidroxi-6-metoxicromam-2-ona, 4[(1E]-3-hidroxi-1-propenil)-2-methoxifenol, piperonal, escoparona, o-guaiacol, espatulenol, seringol e antiarol) foram identificados pela primeira vez nesta espécie. Foram também identificados os triterpenos α-amirina e β-amirina, os esteroides estigmasterol e sitosterol e a cumarina escopoletina, que estão intimamente ligados à atividade antibacteriana da espécie.


Subject(s)
Chemical Compounds/analysis , Burseraceae/classification , Anti-Infective Agents/classification , Staphylococcus aureus/classification , Enterococcus faecalis/classification , Coumarins/pharmacology
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