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1.
Anesthesiology ; 140(4): 752-764, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38207290

RESUMO

BACKGROUND: Lower fractional inspired oxygen tension (Fio2) during general anesthesia can reduce lung atelectasis. The objectives are to evaluate the effect of two Fio2 (0.4 and 1) during low positive end-expiratory pressure (PEEP) ventilation over lung perfusion distribution, volume, and regional ventilation. These variables were evaluated at two PEEP levels and unilateral lung atelectasis. METHODS: In this exploratory study, 10 healthy female piglets (32.3 ± 3.4 kg) underwent mechanical ventilation in two atelectasis models: (1) bilateral gravitational atelectasis (n = 6), induced by changes in PEEP and Fio2 in three combinations: high PEEP with low Fio2 (Fio2 = 0.4), zero PEEP (PEEP0) with low Fio2 (Fio2 = 0.4), and PEEP0 with high Fio2 (Fio2 = 1); and (2) unilateral atelectasis (n = 6), induced by left bronchial occlusion, with the left lung aerated (Fio2 = 0.21) and low aerated (Fio2 = 1; n = 5 for this step). Measurements were conducted after 10 min in each step, encompassing assessment of respiratory mechanics, oxygenation, and hemodynamics; lung ventilation and perfusion by electrical impedance tomography; and lung aeration and perfusion by computed tomography. RESULTS: During bilateral gravitational atelectasis, PEEP reduction increased atelectasis in dorsal regions, decreased respiratory compliance, and distributed lung ventilation to ventral regions with a parallel shift of perfusion to the same areas. With PEEP0, there were no differences between low and high Fio2 in respiratory compliance (23.9 ± 6.5 ml/cm H2O vs. 21.9 ± 5.0; P = 0.441), regional ventilation, and regional perfusion, despite higher lung collapse (18.6 ± 7.6% vs. 32.7 ± 14.5%; P = 0.045) with high Fio2. During unilateral lung atelectasis, the deaerated lung had a lower shunt (19.3 ± 3.6% vs. 25.3 ± 5.5%; P = 0.045) and lower computed tomography perfusion to the left lung (8.8 ± 1.8% vs. 23.8 ± 7.1%; P = 0.007). CONCLUSIONS: PEEP0 with low Fio2, compared with high Fio2, did not produce significant changes in respiratory system compliance, regional lung ventilation, and perfusion despite significantly lower lung collapse. After left bronchial occlusion, the shrinkage of the parenchyma with Fio2 = 1 enhanced hypoxic pulmonary vasoconstriction, reducing intrapulmonary shunt and perfusion of the nonventilated areas.


Assuntos
Atelectasia Pulmonar , Respiração Artificial , Animais , Feminino , Suínos , Respiração Artificial/métodos , Pulmão/diagnóstico por imagem , Medidas de Volume Pulmonar , Atelectasia Pulmonar/diagnóstico por imagem , Atelectasia Pulmonar/terapia , Perfusão , Oxigênio
2.
Childs Nerv Syst ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862794

RESUMO

PURPOSE: Biomarkers are substances measured at the systemic level to evaluate organic responses in certain situations, establishing diagnoses, disease staging, and prognosis. Blood glucose is a biomarker recognized as a predictor of prognosis in children victims of traumatic brain injury (TBI). The scope of this study was to identify the accuracy of blood glucose as a biomarker of severe brain injury. METHODS: A retrospective analytical study was conducted through the consecutive review of medical records of children and teenage victims of TBI who underwent neurological surgery between 2016 and 2023 in a level 1 trauma center. Two groups were compared: children with Glasgow Coma Scale (GCS) score ≤ 8 and children with GCS > 8. We calculated the predictive values to define the accuracy of blood glucose as a biomarker of brain injury. RESULTS: Ninety-two medical records were included for analysis. Hyperglycemia predominated in cases with GCS ≤ 8 (48% vs 3%; p < 0.0001; OR, 30; 95% CI, 5.9902-150.2448). The glycemic measurement considering the cutoff point of 200 mg/dL or 11.1 mmol/L showed a specificity of 97%, a positive predictive value of 86%, an accuracy of 84%, and a likelihood ratio for a positive test of 16. CONCLUSION: Victims with GCS ≤ 8 are 16 times more likely to develop acute hyperglycemia after TBI when compared to those with GCS > 8. Blood glucose is a biomarker with an accuracy of 84% to predict severe brain injury, considering the cutoff point of 200 mg/dL or 11.1 mmol/L.

3.
Pediatr Neurosurg ; 59(2-3): 109-114, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38246161

RESUMO

INTRODUCTION: Pitt-Hopkins syndrome (PTHS) is a rare genetic syndrome associated with neurodevelopmental disorders and craniofacial dysmorphisms caused by variations in the TCF4 transition factor. The aim of this article was to report the case of two twin infants diagnosed with PTHS, confirmed by the identification of a heterozygous pathogenic variant in the TCF4 gene through DNA extracted from a buccal swab. CASE PRESENTATION: Both infants presented with craniofacial asymmetry with a metopic crest and cranial deformity. During the diagnostic investigation, computed tomography with three-dimensional reconstruction of the skull showed premature fusion of the left coronal and metopic sutures in both twins. They underwent craniofacial reconstruction at the 9th month of age using a combination of techniques. The postoperative outcomes were satisfactory in both cases. CONCLUSION: To the best of our knowledge, this is the first case report to describe the occurrence of complex craniosynostosis (CCS) in children with PTHS. Further studies are needed to determine whether the co-occurrence of PTHS and CCS described here indicates an association or is explained by chance.


Assuntos
Craniossinostoses , Hiperventilação , Deficiência Intelectual , Humanos , Craniossinostoses/cirurgia , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/genética , Craniossinostoses/complicações , Deficiência Intelectual/genética , Hiperventilação/genética , Lactente , Feminino , Masculino , Fator de Transcrição 4/genética , Fácies , Doenças em Gêmeos/cirurgia , Doenças em Gêmeos/diagnóstico por imagem , Tomografia Computadorizada por Raios X
4.
Exp Appl Acarol ; 92(1): 27-39, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37985607

RESUMO

Multiple arthropod pests can affect the same crop in agricultural systems, requiring the integration of control methods. In the present study, the effects of residual exposure to four broad-spectrum insecticides/acaricides (azadiractin, abamectin, chlorfenapyr, and fenpyroximate) on immature (development and survival time) and adult females (longevity, fecundity, and fertility life table parameters) of the predatory mite Neoseiulus barkeri were evaluated. Additionally, the insecticides/acaricides were categorized according to their selectivity based on the classification proposed by the International Organization for Biological Control (IOBC) for assessing the susceptibility of arthropods in laboratory experiments. Method 004, proposed by the Insecticide Resistance Action Committee (IRAC), was adopted for the bioassays with predators exposed to insecticide-acaricide residues. Among the insecticides/acaricides studied, azadirachtin had minimal effects on immature and adult N. barkeri (all non-significant) and was considered harmless based on the classification of toxicity according to the standards/categories proposed by the IOBC. All other insecticides/acaricides affected immature and adult N. barkeri and were considered slightly harmful in terms of toxicity, according to the IOBC.


Assuntos
Acaricidas , Inseticidas , Ácaros , Praguicidas , Feminino , Animais , Acaricidas/toxicidade , Praguicidas/farmacologia , Inseticidas/farmacologia , Fertilidade , Comportamento Predatório
5.
Exp Appl Acarol ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888667

RESUMO

Direct and indirect ecological interactions, environmental factors, and the phenology of host plants can shape the way mites interact. These relationships interfere with species occurrence and consequently alter the structure and stability of the intraplant community. As predatory mites act as regulators of herbivorous mites, we hypothesized that these mites may occupy a central position in a network of interactions among mite species associated with mango trees, and the occurrence of these species is mediated by environmental variables and the phenological stage of the host plant. We evaluated the global structure of the interaction network of mites associated with individual Mangifera indica plants and analyzed the interspecific relationships of the species using an undirected Bayesian network approach. Additionally, we observed a correlation between mite population density and plant phenological stage. Environmental variables, such as average monthly temperature, monthly precipitation, and average monthly relative humidity at different sampling date were used in the correlation analysis. The modularity at the mite-plant network level showed a low specialization index H2 = 0.073 (generalist) and high robustness (R = 0.93). Network analysis revealed that Amblyseius largoensis, Bdella ueckermanni, Parapronematus acaciae, and Tuckerella ornata occupied central positions in the assembly of mites occurring on mango trees. Environmental variables, average monthly temperature, and monthly precipitation were correlated with the occurrence of Brachytydeus formosa, Cisaberoptus kenyae, Oligonychus punicae, T. ornata, and Vilaia pamithus. We also observed a correlation between the plant phenological stage and population densities of Neoseiulus houstoni, O. punicae, P. acaciae, and V. pamithus.

6.
Pediatr Transplant ; 27(8): e14555, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37291909

RESUMO

BACKGROUND: The management of complex, intra- and extrahepatic portal vein thrombosis (PVT) after liver transplantation (LT) is challenging. Although most of the patients remain asymptomatic or oligosymptomatic in the chronic setting, some of them may develop severe portal hypertension and related complications, notably gastrointestinal (GI) bleeding. In the emergency scenario, clinical and endoscopic treatments as well as intensive support constitute the bases of conservative management, while more definitive treatment options such as surgical shunting and retransplantation are related to high morbidity rates. Transjugular intrahepatic portosystemic shunt (TIPS) was largely considered of limited role due to technical difficulties arising from extensive PVT. Recently, however, new minimally invasive image-guided techniques emerged, allowing portal vein recanalization and TIPS creation simultaneously (TIPS-PVR), even in complex PVT pretransplant patients. METHODS: Herein, we describe a novel indication for TIPS-PVR in a post-LT adolescent presenting with life-threatening, refractory GI bleeding. RESULTS: The patient presented with complete resolution of the hemorrhagic condition after the procedure, with no deterioration of hepatic function or hepatic encephalopathy. Follow-up Doppler ultrasound after TIPS-PVR showed normal hepatopetal venous flow within the stents, and no evidence of complications, including intraperitoneal or peri splenic bleeding. CONCLUSIONS: This report describes the feasibility of TIPS-PVR in the post-LT scenario complicated by extensive PVT. In this case, a complete resolution of the life-threatening GI bleeding was achieved, with no major complications. Other patients with complex chronic PVT might benefit from the use of the described technique, but further studies are required to determine the correct timing and indications of the procedure, eventually before the occurrence of life-threatening complications.


Assuntos
Varizes Esofágicas e Gástricas , Transplante de Fígado , Derivação Portossistêmica Transjugular Intra-Hepática , Trombose Venosa , Humanos , Adolescente , Veia Porta/cirurgia , Transplante de Fígado/efeitos adversos , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/cirurgia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Trombose Venosa/cirurgia , Trombose Venosa/complicações , Resultado do Tratamento
7.
Sensors (Basel) ; 23(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37447677

RESUMO

Robotic-assisted rehabilitation is currently being applied to improve the effectiveness of human gait rehabilitation and recover the mobility and strength after a stroke or spinal cord injury; a robotic assistant can allow the active participation of the patient and the supervision of the collected data and decrease the labor required from therapists during the patient's training exercises. The goal of gait rehabilitation with robotic-based assistance is to restore motor function by using diverse control strategies, taking account of the physical interaction with the lower limbs of the patient. Over the last few years, researchers have extracted useful information from the patient's biological signals that can effectively reflect movement intention and muscle activation. One way to evaluate progress in rehabilitation is through isokinetic prototype tests that describe the dynamic characteristics of an isokinetic leg extension device for rehabilitation and control action. These tests use an isokinetic system to assess muscle strength and performance in a patient during isometric or isokinetic contraction. An experimental prototype shown in the following work allows the device's performance to be evaluated in a controlled environment before the patient's use. New features provide a control system that can be teleoperated for distributed structures, enabling the remote operation and management of the device. In order to achieve physical recovery from musculoskeletal injuries in the lower limbs and the reintegration of the affected subject into society as an independent and autonomous individual in their daily activities, a control model that introduces a medical isokinetic rehabilitation protocol is presented, in which the element that carries out such protocol consists of a magnetic particle brake whose control action is strongly influenced by the dynamics of the system when in contact with the end user-specifically, the patient's legs in the stretch from the knee to the ankle. The results of these tests are valuable for health professionals seeking to measure their patient's progress during the rehabilitation process and determine when it is safe and appropriate to advance in their treatment.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Terapia por Exercício , Joelho , Marcha , Articulação do Joelho
8.
Sensors (Basel) ; 23(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37448053

RESUMO

The present study contains an experimental analysis of the vibratory response in a low-cylinder engine motorcycle at varying suspension preloads. Three different speed bumps of varying heights were used to subject the motorcycle to different vibrations. The analysis was carried out in three domains: time, frequency, and time-frequency. A triaxial accelerometer was used to measure the vibrations at the seat of the vehicle. The results indicated that the suspension system became more differentiated as the height of the bumps increased. However, for lower bumps, the action of the three spring preloads studied was quite similar. Quantitatively, only the higher bump showed a significant difference between the set preloads. The spectral distribution revealed that the frequency of interest was below 20 Hz for all the studied cases, which is in the same range of human body natural frequencies. The findings of this research can be utilized to enhance the design of low-cost motorcycles, thereby improving the safety and comfort of their drivers and passengers. This study constitutes a significant step towards developing an affordable system capable of gathering sufficient data to support the creation of evidence-based public health policies and propose new transport industry standards based on field measurements.


Assuntos
Motocicletas , Vibração , Humanos , Acidentes de Trânsito
9.
Exp Appl Acarol ; 90(1-2): 19-31, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37322232

RESUMO

The meristematic region of Cocos nucifera fruits can be colonized by various species of mites, including Steneotarsonemus concavuscutum, Steneotarsonemus furcatus, and Aceria guerreronis. The consequence of this colonization is the development of necrotic lesions on the fruit, and sometimes its abortion. Losses are commonly attributed to A. guerreronis alone, owing to the similarities in the injuries caused and its predominance in coconut plantations. However, S. concavuscutum may be the predominant pest species in some crops. Despite the possible impact of S. concavuscutum, little is known about its bioecological aspects, such as the influence of biotic and abiotic factors on its population dynamics. Our objective was to document macroclimatic abiotic factors (temperature, relative humidity, and precipitation) and biotic factors (interspecific competition and predation) interfere in the population dynamics of S. concavuscutum. We evaluated the diversity and abundance of mites in the perianth of coconut fruit naturally infested by S. concavuscutum for 1 year. The species found in the fruits of bunch 6 of the plant, which is the fruit age at which the mites commonly reach the highest abundance, were counted every 2 weeks. We found mites from nine families and S. concavuscutum was the predominant species, representing about 92% of the individuals collected. Predators represented approximately 2% of the total collection, with Neoseiulus baraki as the predominant species. Steneotarsonemus concavuscutum population density ranged from 60 to 397 mites/fruit. The highest population densities of S. concavuscutum were observed in the hottest and driest periods of the year. The population densities of S. concavuscutum were negatively associated with the presence of N. baraki, suggesting that this predator may have a role in the biological control of this pest.


Assuntos
Ácaros , Animais , Frutas , Cocos , Temperatura , Dinâmica Populacional
10.
Environ Monit Assess ; 195(5): 593, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37079116

RESUMO

The objective of the study is to perform the spatial analysis of the conditioning factors for the increase in the incidence rate of dengue cases in municipalities located in the Amazon biome, in the period from 2016 to 2021. Three statistical approaches were applied: Moran's index, ordinary least squares regression, and geographically weighted regression. The results revealed that the incidence rates of dengue cases cluster in two areas, both located in the south of the Amazon biome, which is associated with the Arc of Deforestation. The variable deforestation influences the increase in dengue incidence rates revealed by the OLS and GWR model. The adjusted R2 of the GWR model was 0.70, that is, the model explains about 70% of the total case variation of dengue incidence rates in the Amazon biome. The results of the study evidence the need for public policies aimed at the prevention and combat of deforestation in the Amazon region.


Assuntos
Conservação dos Recursos Naturais , Dengue , Humanos , Incidência , Brasil/epidemiologia , Monitoramento Ambiental , Dengue/epidemiologia
11.
J Appl Microbiol ; 132(3): 1802-1812, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34689393

RESUMO

AIMS: Aeromonas hydrophila is an opportunistic bacterium, with a high capacity for biofilm production, which can cause severe damage in aquaculture. The objective of this study was to identify the chemical compounds of the essential oils of Lippia sidoides (EOLS) and Cymbopogon citratus (EOCC), and to evaluate the biocidal, antibiofilm and synergistic action with the antimicrobial florfenicol of these essential oils (EOs) against A. hydrophila. METHODS AND RESULTS: The antibacterial activity of EOLS and EOCC was verified by the minimum bactericidal concentration and by the action of these EOs against both forming and consolidated biofilms. The synergistic activity of EOs with florfenicol was performed using the checkerboard technique. The main component of EOLS and EOCC was carvacrol (44.50%) and α-citral (73.56%), respectively. Both EOs showed weak inhibitory activity (≥3125.00 µg ml-1 ). Two bacterial isolates were able to produce biofilm, and EOLS and EOCC acted upon the bacterial isolates to prevent biofilm formation. A bactericidal effect was verified for EOLS in the previously consolidated biofilm for both isolates and for EOCC in only one of the isolates. In general, EOLS had a synergistic effect with florfenicol, while EOCF had an additive effect. CONCLUSIONS: Both EOs were able to interfere with biofilm formation and did not have an antagonistic effect in combination with florfenicol. The best results were found for EOLS, which showed a synergistic effect with florfenicol and the ability to interfere in the formation of consolidated biofilm. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights the potential of EOLS and EOCC to interfere in biofilm and act in synergy with florfenicol to reduce the occurrence of A. hydrophila. Development of these compounds may contribute to the development of herbal medicines in aquaculture.


Assuntos
Cymbopogon , Lippia , Óleos Voláteis , Aeromonas hydrophila , Antibacterianos/química , Antibacterianos/farmacologia , Biofilmes , Lippia/química , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Tianfenicol/análogos & derivados
12.
J Nat Prod ; 85(9): 2184-2191, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-35998343

RESUMO

Herein, the isolation of secondary metabolites from the aerial parts of Justicia aequilabris guided by HPLC-MSn and molecular networking analyses is reported. Twenty-two known compounds were dereplicated. Three new lignans (aequilabrines A-C (1-3)) and three known compounds (lariciresinol-4'-O-ß-glucose (4), roseoside (5), and allantoin (6)) were obtained. The anti-inflammatory activity of compounds 1-3 was evaluated in vitro by inhibiting the nitric oxide production (NO) and pro-inflammatory activity on the cytokine IL-1ß. Compounds 2 and 3 showed significant inhibitory activity against NO production, with IC50 values of 9.1 and 7.3 µM, respectively. The maximum inhibition of IL-1ß production was 23.5% (1), 27.3% (2), and 32.5% (3).


Assuntos
Anti-Inflamatórios , Justicia , Lignanas , Alantoína/química , Alantoína/isolamento & purificação , Alantoína/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Furanos/química , Furanos/isolamento & purificação , Furanos/farmacologia , Lignanas/química , Lignanas/isolamento & purificação , Lignanas/farmacologia , Estrutura Molecular , Óxido Nítrico/antagonistas & inibidores , Extratos Vegetais/química
13.
Childs Nerv Syst ; 38(11): 2149-2154, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35948831

RESUMO

PURPOSE: To estimate the costs of the surgical treatment of pediatric hydrocephalus, specifically ventriculoperitoneal shunt (VPS) and endoscopic third ventriculostomy (ETV), for the Brazilian public health system (SUS). METHODS: Retrospective cohort study of health records of patients < 14 years of age with a diagnosis of hydrocephalus who underwent VPS or ETV between September 2009 and June 2016, regularly followed up for 24 months. RESULTS: Seventy-six medical records were included. The groups of children who underwent VPS and ETV consisted of 60 and 16 patients, respectively. Complications during 2 years of follow-up were identified in 56% of the children undergoing VPS and in 18% of those undergoing ETV (p = 0.0103). The initial cost of VPS was lower than that of ETV up to approximately 1 year of post-surgical follow-up. After that, VPS generated higher expenses for the SUS due to higher rates of late post-surgical complications and repeated readmissions. CONCLUSION: Higher public expenditures were observed in the group of children undergoing VPS due to higher rates of infectious and mechanical complications requiring repeated hospitalizations and prosthesis replacements. Public policies must be tailored to offer the best treatment to children with hydrocephalus and to make judicious use of public resources without compromising the quality of treatment.


Assuntos
Hidrocefalia , Neuroendoscopia , Terceiro Ventrículo , Humanos , Criança , Lactente , Brasil , Estudos Retrospectivos , Saúde Pública , Neuroendoscopia/efeitos adversos , Resultado do Tratamento , Hidrocefalia/etiologia , Ventriculostomia/efeitos adversos , Derivação Ventriculoperitoneal/efeitos adversos , Terceiro Ventrículo/cirurgia
14.
An Acad Bras Cienc ; 94(2): e20191244, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544843

RESUMO

The vegetable leaf miner (Liriomyza sativae) is considered one of the main melon pests, causing serious problems for producers in all growing regions. A promising type of pest control has been use of resistant cultivars, in isolation or associated with other types of control. This study aimed to evaluate the resistance of melon genotypes to L. sativae. Twenty-one melon genotypes and one commercial "Goldex" hybrid (susceptibility pattern) were evaluated in two experiments. In the first experiment, we observed the non-preference of L. sativae for oviposition and feeding by quantifying the number of eggs and feeding punctures, both on the adaxial side and on the abaxial face of the leaves. In the second experiment, we observed the antibiosis effect through L. sativae larval and pupal viability. Genotype CNPH 06-1047-341 showed the lowest preference for oviposition (high resistance), with low egg values on both leaf sides (0.3 eggs/plant). In genotypes CNPH 06-1047-313, CNPH 06-1047-346, CNPH 11-1071-27, CNPH 11-1071-39, CNPH 11-1071-43, and CNPH 11-1071-53, we observed a higher preference for the adaxial side, whereas for the other genotypes and the commercial hybrid there was no discrimination between leaf sides. In relation to antibiosis, genotypes CNPH 06-1047-339, CNPH 06-1047-333, CNPH 06-1047-330, CNPH 06-1047-334, CNPH 06-1047-331, CNPH 06-1047-343, CNPH 10-1056-313, CNPH 06-1047-346, and CNPH 06-1047-341 presented lower larval and pupal viability. Genotype CNPH 06-1047-341 was the least preferred for oviposition and feeding and the most promising as a source of resistance to L. sativae.


Assuntos
Cucurbitaceae , Dípteros , Animais , Dípteros/genética , Feminino , Genótipo , Larva , Pupa
15.
Sensors (Basel) ; 22(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36433466

RESUMO

The detection of bond-slip between the reinforcing bar (RB) and concrete is of great importance to ensure the safety of reinforced concrete (RC) structures. The techniques to monitor the connection between the RB and concrete are in constant development, with special focus on the ones with straightforward operation and simple non-intrusive implementation. In this work, a simple configuration is developed using 10 optical fiber sensors, allowing different sections of the same RC structure to be monitored. Since the RB may suffer different strains along its length, the location of the sensors is critical to provide an early warning about any displacement. Bragg gratings were inscribed in both silica and polymer optical fibers and these devices worked as displacement sensors by monitoring the strain variations on the fibers. The results showed that these sensors can be easily implemented in a civil construction environment, and due to the small dimensions, they can be a non-intrusive technique when multiple sensors are implemented in the same RC structure.

16.
Molecules ; 27(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36144723

RESUMO

Mandevilla Lindl. is an important genus of the Apocynaceae family, not only as ornamental plants but also for its medicinal uses. In Brazil, Mandevilla species are indicated to treat asthma and skin infections, their anti-inflammatory potential and wound healing properties are also reported in the literature. Concerning their chemical composition, this group of plants is a conspicuous producer of pregnane glycosides. Mandevilla dardanoi is an endemic species from the Brazilian semiarid region not studied by any phytochemical methods. In view of the medicinal potential of Mandevilla species, this study aimed to isolate new pregnane glycosides from M. dardanoi. To achieve this main goal, modern chromatography techniques were employed. Five new pregnane glycosides, dardanols A-E, were isolated from the roots of M. dardanoi by HPLC. Their structures were determined using extensive 1D and 2D-NMR and mass spectrometry (MSn and HRESIMS) data. The cytotoxicity and the anti-inflammatory potential of these compounds were evaluated. The first was evaluated by measuring proinflammatory cytokines and nitric oxide production by stimulated macrophages. Dardanols were able to inhibit the production of nitric oxide and reduce IL-1ß and TNF-α. The current work demonstrates the chemodiversity of Brazilian semiarid species and contributes to amplifying knowledge about the biological potential of the Mandevilla genus.


Assuntos
Apocynaceae , Óxido Nítrico , Anti-Inflamatórios/farmacologia , Apocynaceae/química , Glicosídeos/química , Glicosídeos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas , Pregnanos/química , Pregnanos/farmacologia , Fator de Necrose Tumoral alfa
17.
An Acad Bras Cienc ; 93(suppl 4): e20201541, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34706003

RESUMO

The objective of this study was to evaluate the effect of pure glucose, glucose plus fructose, and fructose on the blood glucose of omnivorous fish tambaqui (Colossoma macropomum), Nile tilapia (Oreochromis niloticus), piau (Leporinus elongatus), and carnivorous fish hybrid Amazon catfish (Pseudoplatystoma fasciatum × Leiarius marmoratus), pacamã (Lophiosilurus alexandri), and traíra (Hoplias malabaricus). In each species, the dose 1 mL per fish with 1,000 mg kg of body weight-1 of glucose, fructose or glucose plus fructose were tested intraperitoneally. Blood glucose was measured at times 0 (control), 0.5, 1, 2, 4, 8, 16, and 24 h. The administration of 1,000 mg of glucose or glucose plus fructose per kg of live weight causes hyperglycemia in the omnivorous and carnivorous species studied. In the omnivorous species, glycemic levels were reduced from 2 to 4 h, and the regulation to baseline occurred from 4 to 8 h. In the carnivores fish, blood glucose levels declined between 1 and 8 h, and return to baseline was observed from 8 to 16 h. Tambaqui was also intolerant to high concentrations of fructose. Blood glucose levels are regulated in a shorter time in Nile tilapia (mainly), piau and pacamã.


Assuntos
Peixes-Gato , Caraciformes , Ciclídeos , Animais , Brasil , Glucose
18.
Trop Anim Health Prod ; 53(4): 410, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34297225

RESUMO

The objective of this study was to evaluate the potential of mesquite bean flour (Prosopis juliflora) as an energy ingredient in extruded diets for juvenile Nile tilapia (Oreochromis niloticus). Two experiments were carried out: the first consisted of a study to evaluate the chemical composition and digestibility of the energy and nutrients of MBF; the second consisted of a growth test, in which juveniles consumed diets containing different proportions of corn substitution by MBF, in which zootechnical, hematological, physiological, and metabolic variables were evaluated. It was observed that MBF has a chemical composition similar to corn, as well as the apparent digestibility of energy and nutrients. The higher sucrose/starch ratio of the ingredient stands out, as well as the difference in digestibility (p < 0.05) between the predominant carbohydrates 87.63 and 99.25% for starch and sucrose, respectively. In the growth assay, no difference was observed between zootechnical variables (p > 0.05), and sucrase and alkaline phosphatase activities were increased (p < 0.05), which was not observed for amylase and lipase (p > 0.05). The hematological variables did not change (p > 0.05). Metabolic variables indicate a reduction in gluconeogenesis from amino acids, as can be seen by the reduction in liver transaminase levels (ALT and AST) and glutamate dehydrogenase (GDH), as well as the greater availability of free amino acids in plasmas (p < 0.05). Thus, it can be said that MBF has a high nutritional value and can totally replace corn in diets for juvenile tilapia and the metabolic findings indicate a potential protein-sparing effect.


Assuntos
Ciclídeos , Prosopis , Ração Animal/análise , Animais , Dieta/veterinária , Farinha , Zea mays
19.
An Acad Bras Cienc ; 92 Suppl 1: e20190412, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32638861

RESUMO

Abstract: The dispersion capacity is fundamental to establish a biological control program with parasitoids. This information is used to determine the efficiency and the number of release points. Thus, the objective of this work was to determine the dispersion and to estimate the number of release points of Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae), in sweet corn, cucumber and cabbage in the Ceará State. The experiments were carried out in areas of maize with four leaf pairs (V4) and eight leaves pair (V8), stacked and cabbage. Unviable eggs of an alternative host were distributed in concentric circles of radius 2.5; 5.0; 9.0 and 12.0 m. Mean dispersal distance in the V4 stage maize was 4.7 m with a dispersion area of 48.6 m2, parasitism index of 18.4%, requiring 206 points/ha. In the V8 stage maize, the mean distance was 5.9 m, dispersion area of 60.3 m², mean parasitism index of 22.7% and 166 release points/ha. For the cucumber culture the mean distance was 6.0 m, dispersion area 62.2 m², mean parasitism index of 21.1% and 161 release points/ha. For cabbage the mean distance was 5.6 m, dispersion area of 56.8 m², mean parasitism index of 22.1% and 176 release points/ha.


Assuntos
Cucumis sativus , Himenópteros , Animais , Brassica , Mariposas , Controle Biológico de Vetores , Vespas , Zea mays
20.
An Acad Bras Cienc ; 92 Suppl 1: e20190140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32638863

RESUMO

The objective of the present study was to evaluate growth, biochemical, hematological and intestinal enzymes responses and survival of Nile tilapia juveniles fed a diet containing the essential oil of lemongrass Cymbopogum flexuosus (EOCF) and infected by Aeromonas hydrophila. Five diets were evaluated (in quadruplicate) with increasing levels of EOCF (0.0 - control; 0.25; 0.50; 1.0 and 2.0 mL kg diet-1). On day 45, eight fish per treatment were sampled and blood, liver and intestine samples were taken. Others eight fish per treatment were infected with A. hydrophila followed by a 15-day period of observation. Citral is the main constituent of EOCF. The inclusion of 2.0 mL EOCF kg diet-1 increased specific growth rate and survival after A. hydrophila infection and decreased feed conversion ratio of Nile tilapia. In general, higher concentrations of EOCF in the diet reduced plasma glucose and triglycerides levels, and increased plasma amino acids, alanine aminotransferase (ALT) and hepatic ALT levels, hematological parameters, and the activity of intestinal enzymes. It was concluded that the inclusion of 2.0 mL EOCF kg diet-1 improved growth performance, biochemical and physiological responses and decreased mortality of Nile tilapia after A. hydrophila infection.


Assuntos
Ciclídeos , Cymbopogon , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Aeromonas hydrophila , Ração Animal , Animais , Dieta , Suplementos Nutricionais , Infecções por Bactérias Gram-Negativas/veterinária , Óleos Voláteis
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