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1.
BMC Plant Biol ; 20(1): 467, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33045997

RESUMO

BACKGROUND: This study describes a promising method for understanding how halophytes adapt to extreme saline conditions and to identify populations with greater resistance. Image and colour analyses have the ability to obtain many image parameters and to discriminate between different aspects in plants, which makes them a suitable tool in combination with genetic analysis to study the plants salt tolerance. To the best of our knowledge, there are no publications about the monitoring of halophytic plants by non-destructive methods for identifying the differences between plants that belong to different maternal salinity environments. The aim is to evaluate the ability of image analysis as a non-destructive method and principal component analysis (PCA) to identify the multiple responses of two S. europaea populations, and to determine which population is most affected by different salinity treatments as a preliminary model of selection. RESULTS: Image analysis was beneficial for detecting the phenotypic variability of two S. europaea populations by morphometric and colour parameters, fractal dimension (FD), projected area (A), shoot height (H), number of branches (B), shoot diameter (S) and colour change (ΔE). S was found to strongly positively correlate with both proline content and ΔE, and negatively with chlorophyll content. These results suggest that proline and ΔE are strongly linked to plant succulence, while chlorophyll decreases with increased succulence. The negative correlation between FD and hydrogen peroxide (HP) suggests that when the plant is under salt stress, HP content increases in plants causing a reduction in plant complexity and foliage growth. The PCA results indicate that the greater the stress, the more marked the differences. At 400 mM a shorter distance between the factorial scores was observed. Genetic variability analysis provided evidence of the differences between these populations. CONCLUSIONS: Our non-destructive method is beneficial for evaluating the halophyte development under salt stress. FD, S and ΔE were relevant indicators of plant architecture. PCA provided evidence that anthropogenic saline plants were more tolerant to saline stress. Furthermore, random amplified polymorphic DNA analysis provided a quick method for determining genetic variation patterns between the two populations and provided evidence of genetic differences between them.


Assuntos
Chenopodiaceae/crescimento & desenvolvimento , Chenopodiaceae/genética , Salinidade , Tolerância ao Sal/genética , Tolerância ao Sal/fisiologia , Plantas Tolerantes a Sal/genética , Plantas Tolerantes a Sal/fisiologia , Fractais , Variação Genética , Genótipo , Polônia
2.
Microsc Microanal ; 25(4): 989-997, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31272515

RESUMO

Here, different tissue surfaces of tomato root were characterized employing atomic force microscopy on day 7 and day 21 of growth through Young's modulus and plasticity index. These parameters provide quantitative information regarding the mechanical behavior of the tomato root under fresh conditions in different locations of the cross-section of root [cell surface of the epidermis, parenchyma (Pa), and vascular bundles (Vb)]. The results show that the mechanical parameters depend on the indented region, tissue type, and growth time. Thereby, the stiffness increases in the cell surface of epidermal tissue with increasing growth time (from 9.19 ± 0.68 to 13.90 ± 1.68 MPa) and the cell surface of Pa tissue displays the opposite behavior (from 1.74 ± 0.49 to 0.48 ± 0.55); the stiffness of cell surfaces of Vb tissue changes from 10.60 ± 0.58 to 6.37 ± 0.53 MPa, all cases showed a statistical difference (p < 0.05). Viscoelastic behavior dominates the mechanical forces in the tomato root. The current study is a contribution to a better understanding of the cell mechanics behavior of different tomato root tissues during growth.


Assuntos
Fenômenos Biomecânicos , Microscopia de Força Atômica/métodos , Raízes de Plantas/crescimento & desenvolvimento , Solanum lycopersicum/crescimento & desenvolvimento , Elasticidade , Fatores de Tempo
3.
Med Oral Patol Oral Cir Bucal ; 24(4): e438-e443, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31232393

RESUMO

BACKGROUND: The aim of the present study is to analyse the variables associated with the family care of people diagnosed with serious mental illness. MATERIAL AND METHODS: A cross-sectional study was carried out involving caregivers of people with serious mental illness (SMI) who were known to the mental health services in Valencia (España) and associations for those with SMI. The sample comprised 417 caregivers who completed a sociodemographic questionnaire and the Zarit Burden Interview. Bivariate analyses (t-test, analysis of variance and Pearson correlation) were performed, as was a multiple linear regression model. Values of p < .05 were considered significant. The study was carried out in accordance with the recommendations of the ethics committees of the participating institutions. RESULTS: The statistical analyses showed significant associations between the sociodemographic and clinical variables of the caregivers and patients and the burden felt by caregivers of people with SMI. The importance of both formal and informal social support stands out as a protective factor against the consequences of the illness's impact on the main caregiver. CONCLUSIONS: The role of spaces of mutual support is crucial. The results suggest that family psychoeducational programmes should be created, applied and evaluated in all mental healthcare services so as to reinforce training in mental health matters and provide support and assessment to caregivers in order to ease their burden.


Assuntos
Transtornos Mentais , Cuidadores , Estudos Transversais , Humanos , Fatores de Risco , Apoio Social
4.
J Food Sci Technol ; 56(11): 4992-4999, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31741523

RESUMO

The marine bacterium Stenotrophomonas rhizophila was assessed in vitro and in vivo as biocontrol agent against anthracnose disease of mango fruit caused by Colletotrichum gloeosporioides. The results showed that in vitro inhibition of the colony diameter and spore germination of the phytopathogen was due to the production of VOCs, competition for nutrients, and lytic enzymes. When a concentration of 1 × 108 cells ml-1 of the antagonist bacterium was applied to the fruit, disease incidence was reduced by 95%, and the lesion diameter of anthracnose decreased by 85%, which offered greater protection than the synthetic fungicide. This is the first report of antagonistic mechanisms of the marine bacterium S. rhizophila against anthracnose disease in mango, which in this study was found to be more effective than the synthetic fungicide.

5.
Ultrasound Obstet Gynecol ; 51(1): 150-155, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29297616

RESUMO

Ultrasound imaging has become integral to the practice of obstetrics and gynecology. With increasing educational demands and limited hours in residency programs, dedicated time for training and achieving competency in ultrasound has diminished substantially. The American Institute of Ultrasound in Medicine assembled a multi-Society Task Force to develop a consensus-based, standardized curriculum and competency assessment tools for obstetric and gynecologic ultrasound training in residency programs. The curriculum and competency-assessment tools were developed based on existing national and international guidelines for the performance of obstetric and gynecologic ultrasound examinations and thus are intended to represent the minimum requirement for such training. By expert consensus, the curriculum was developed for each year of training, criteria for each competency assessment image were generated, the pass score was established at or close to 75% for each, and obtaining a set of five ultrasound images with pass score in each was deemed necessary for attaining each competency. Given the current lack of substantial data on competency assessment in ultrasound training, the Task Force expects that the criteria set forth in this document will evolve with time. The Task Force also encourages use of ultrasound simulation in residency training and expects that simulation will play a significant part in the curriculum and the competency-assessment process. Incorporating this training curriculum and the competency-assessment tools may promote consistency in training and competency assessment, thus enhancing the performance and diagnostic accuracy of ultrasound examination in obstetrics and gynecology. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Competência Clínica/normas , Ginecologia/educação , Obstetrícia/educação , Ultrassonografia , Acreditação , Consenso , Currículo , Ginecologia/normas , Humanos , Internato e Residência , Obstetrícia/normas , Garantia da Qualidade dos Cuidados de Saúde , Ultrassonografia/normas
6.
Eur J Pharmacol ; 969: 176454, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38417607

RESUMO

Estrogen hormone replacement therapy (EHRT), improving women's life quality at menopause, reduces anxiety and depression symptoms associated with ovarian hormonal decline. However, its potential adverse effects, like thromboembolism and cancer risk, limit its use. Prolame is a synthetic 17ß-amino estrogen with antithrombotic actions that exerts anxiolytic- and antidepressant-like effects on young adult ovariectomized female rats. It is unknown if prolame's effects may be observed in age and endocrine conditions emulating menopause. This study aimed to identify the antidepressant- and anxiolytic-like effects of prolame and E2 (used as a reference estrogen treatment) in middle-aged female rats coursing with irregular cycles, in two different conditions: ovariectomized or gonadally intact. Results were compared with those from young adult ovariectomized rats. Prolame (60 or 120 µg/kg), 17ß-estradiol (E2, 40 or 80 µg/kg), or vehicle were chronically administered, and their effects were evaluated in the elevated plus-maze, defensive burying behavior test, open field test, and forced swimming test. Uterotrophic actions were estimated by uterine weight related to body weight. Prolame and E2 produced robust anxiolytic- and antidepressant-like effects in young adult ovariectomized rats, but these effects were absent in gonadally intact middle-aged rats. Interestingly, only prolame induced anxiolytic- and antidepressant-like effects in middle-aged ovariectomized rats. Uterotrophic effects of prolame were weaker than E2 effects, notably in middle-aged females. Altogether, present data support the notion that prolame has the potential to be considered an EHRT with relevant psychoactive actions and with apparently lower adverse-side effects, especially in middle-aged populations.


Assuntos
Ansiolíticos , Estrenos , Humanos , Ratos , Feminino , Animais , Pessoa de Meia-Idade , Ansiolíticos/farmacologia , Ansiolíticos/uso terapêutico , Ratos Wistar , Estradiol/farmacologia , Estradiol/uso terapêutico , Estrogênios/farmacologia , Estrogênios/uso terapêutico , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Ovariectomia/efeitos adversos
7.
Int J Biol Macromol ; 275(Pt 2): 133679, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971282

RESUMO

Arthrospira maxima is a source of phycobiliproteins with different nutraceutical properties, e.g. antioxidant and anti-inflammatory activities. The current study was aimed at the elaboration, characterization, and evaluation of the anti-inflammatory effect of the phycobiliprotein nanoparticles extracted from Arthrospira maxima. Previously freeze-dried phycobiliproteins were milled by high-energy ball milling until reaching a nanometric size (optimal time: 4 h). Microscopy techniques were used for the characterization of the size and morphology of phycobiliproteins nanoparticles. Additionally, a spectroscopic study evidenced that nanosized reduction induced an increase in the chemical functional groups associated with its anti-inflammatory activity that was tested in a murine model, showing an immediate inflammatory effect. The novelty and importance of this contribution was to demonstrate that high energy ball milling is an emerging and green technology that can produce phycobiliprotein nanoparticles on a large-scale, without the use of organic solvents, to test their nutraceutical properties in a biological model by intragastric administration.

9.
Plant Physiol Biochem ; 170: 249-254, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34922141

RESUMO

The objective of this study was to evaluate the effect of the presence of calcium oxalate (CaOx) crystals on the micromechanical properties of sclerenchyma tissue from the pecan nutshell (Carya illinoinensis). The microstructure of the cross-section nutshell was examined using light microscopy (LM) and atomic force microscopy (AFM). Using an instrumented indentation system, indentation tests with maximum loads of 500 mN were made on the biological material where the variables studied were the number of crystals present in the evaluated area and the size of individual crystals. Microscopic analysis revealed that the pecan nutshell consists of sclerenchyma tissue with multiple CaOx crystals randomly distributed throughout the material, exhibiting prismatic shapes and various sizes. The results of the indentation tests showed that the examined areas where there were crystals (1, 2 or up to 3) presented values of hardness and elastic modulus significantly higher (P < 0.05) compared to the sclerenchyma (without crystals). Likewise, there were no significant differences (P > 0.05) between the values of the micromechanical properties of the areas evaluated as a function of the number of crystals. On the other hand, it was observed that the size of the crystals did not show a direct correlation with the mechanical properties evaluated as expected. In conclusion, the biomineralization phenomenon is a successful strategy designed by nature to improve the rigidity of the pecan nutshell, where the CaOx crystals strengthen the structure by increasing the micromechanical properties.


Assuntos
Carya , Oxalato de Cálcio
10.
J Mech Behav Biomed Mater ; 130: 105190, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35344757

RESUMO

In the present work a comprehensive characterization of the hierarchical architecture of the walnut shell (Juglans regia L.) was carried out using scanning electron microscopy (SEM), atomic force microscopy (AFM) and confocal laser scanning microscopy (CLSM). Furthermore, micromechanical properties (hardness, HIT and elastic modulus, EIT) of plant tissues were evaluated at cell wall level by applying the instrumented indentation technique (IIT). The complex architecture of the material was described in terms of four hierarchical levels (HL): endocarp (H1), plant tissues (H2), plant cells (H3) and cell wall (H4). Our findings revealed that the walnut shell consists of a multilayer structure (sclerenchyma tissue, ST; interface tissue, IT; porous tissue, PT; and flattened parenchyma tissue, FPT), where differences in the microstructure and composition of plant tissues generate parallel gradients along the cross-section. The indentation tests showed a functional gradient with a sandwich-like configuration, i.e., a lightweight and soft layer (PT, HIT = 0.04 GPa) is located between two dense and hard layers (ST, HIT = 0.33 GPa; FPT, HIT = 0.28 GPa); where additionally there is an interface between ST and PT (IT, HIT = 0.16 GPa). This configuration is a successful strategy designed by nature to improve the protection of the kernel by increasing the strength of the shell. Therefore, the walnut shell can be considered as a functionally graded material (FGM), which can be used as bioinspiration for the design of new functional synthetic materials. In addition, we proposed some structure-property-function relationships in the whole walnut shell and in each of the plant tissues.


Assuntos
Juglans , Parede Celular , Juglans/química
11.
Micron ; 152: 103183, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34801959

RESUMO

Campylobacter jejuni is a pathogen bacterium that causes foodborne gastroenteritis in humans. However, phenolic compounds extracted from natural sources such as capsicum pepper plant (Capsicum annuum L. var. aviculare) could inhibit the growth of C. jejuni. Therefore, different extracts were prepared using ultrasonic extraction (USE), conventional extraction (CE) and thermosonic extraction (TSE). C. jejuni was then exposed to chili extracts to examine the antimicrobial effect and their growth/death bacterial kinetics were studied using different mathematical models. Atomic force microscopy was applied to investigate the microstructural and nanomechanical changes in the bacteria. Extracts obtained by TSE had the highest phenolic content (4.59 ± 0.03 mg/g of chili fresh weight [FW]) in comparison to USE (4.12 ± 0.05 mg/g of chili FW) and CE (4.28 ± 0.07 mg/g of chili FW). The inactivation of C. jejuni was more efficient when thermosonic extract was used. The Gompertz model was the most suitable mathematical model to describe the inactivation kinetics of C. jejuni. Roughness and nanomechanical analysis performed by atomic force microscopy (AFM) provided evidence that the chili extracts had significant effects on morphology, surface, and the reduced Young's modulus of C. jejuni. The novelty of this work was integrating growth/death bacterial kinetics of C. jejuni using different mathematical models and chili extracts, and its relationship with the morphological, topographic and nanomechanical changes estimated by AFM.


Assuntos
Campylobacter jejuni , Capsicum , Humanos , Cinética , Microscopia de Força Atômica , Extratos Vegetais/farmacologia
12.
RSC Adv ; 10(10): 5712-5721, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35497434

RESUMO

A planar solid-state photocapacitor with two electrodes has been prepared for the first time using a passivated film of ZnS with Ag2S quantum dots deposited on ZnO nanorods, which were electrochemically grown on ZnO seed layers, as the photoanode. The supercapacitor part is composed of a electrodeposited poly(3,4-ethylene-dioxythiophene) PEDOT film as the counter-electrode and an ionic liquid-based electrolyte between them deposited by the dip coating method. The different nanostructures and electrodes were morphologically and structurally characterized, and the device was electrochemically characterized and could reach a potential of 0.33 V during photocharge and a storage efficiency of 6.83%.

13.
Math Biosci ; 328: 108428, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32712317

RESUMO

We consider a non homogeneous Gompertz diffusion process whose parameters are modified by generally time-dependent exogenous factors included in the infinitesimal moments. The proposed model is able to describe tumor dynamics under the effect of anti-proliferative and/or cell death-induced therapies. We assume that such therapies can modify also the infinitesimal variance of the diffusion process. An estimation procedure, based on a control group and two treated groups, is proposed to infer the model by estimating the constant parameters and the time-dependent terms. Moreover, several concatenated hypothesis tests are considered in order to confirm or reject the need to include time-dependent functions in the infinitesimal moments. Simulations are provided to evaluate the efficiency of the suggested procedures and to validate the testing hypothesis. Finally, an application to real data is considered.


Assuntos
Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Biológicos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carboplatina/administração & dosagem , Simulação por Computador , Feminino , Humanos , Conceitos Matemáticos , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem , Processos Estocásticos
14.
Micron ; 118: 50-57, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30590254

RESUMO

In this work, the porosity of the layers of calcified chicken eggshell (vertical crystal layer VCL, palisade layer PL and mammillary layer ML) was evaluated using atomic force microscopy (AFM) and image processing (IP). AFM topographic images were obtained from different locations for each layer and along the cross-section of calcified eggshell. Roughness parameters, surface area values, pore size and shape, surface porosity, area occupied by pores and pore density were obtained from AFM and IP. It was observed that the thickest layer (PL) exhibited the highest degree of porosity (surface porosity = 2.75 ± 1.68%, pore density = 162 ± 60 pores/µm2) when compared to the other two layers. In general, the pores located in all layers ("bubble pores") had circular shape and similar sizes. Measurements revealed a porosity gradient along the cross-section which varied with position, i.e., increasing surface porosity from the VCL towards the region of the PL closer to the ML, and decreasing surface porosity from this location towards the ML innermost surface. This suggests that the calcified eggshell has a sandwich-like structure where porosity may influence gas exchange and mechanical properties. The combination of AFM with IP presented here provides a simple and precise method to study porosity in calcified chicken eggshell, and this methodology could be used to examine other types of porous biological materials.

15.
Prog Neuropsychopharmacol Biol Psychiatry ; 32(8): 1798-803, 2008 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18722496

RESUMO

The objective of this study was to establish the effect of aging on the development of anhedonia, a core feature of depression. Young and old male Wistar rats (of around 3-5 and 12-15 months, respectively) were exposed to a chronic variable stress (CVS) schedule for 3 weeks. CVS produced anhedonia, indicated by a reduction in the intake of a sucrose solution (1%), in 8 out of 23 (35%) young rats and in 19 out of 26 (73%) old rats, implying that old animals are more susceptible to stress and develop anhedonia more readily than young animals. Young and old anhedonic rats showed a similar temporal course in the reduction of sucrose consumption, reaching the anhedonic state after 2 weeks of CVS exposure. Compared with young animals, old rats had lower basal serum testosterone and estradiol levels. The systemic levels of corticosterone did not vary between both age groups. No significant pathological condition was detected in old animals. It is suggested that the higher susceptibility to develop anhedonia in male rats could be associated to neuroendocrine changes consequent to aging.


Assuntos
Envelhecimento , Depressão/etiologia , Suscetibilidade a Doenças , Estresse Psicológico/complicações , Análise de Variância , Animais , Doença Crônica , Condicionamento Operante/fisiologia , Corticosterona/sangue , Depressão/sangue , Ingestão de Líquidos/fisiologia , Ingestão de Alimentos/fisiologia , Estradiol/sangue , Preferências Alimentares , Masculino , Ratos , Ratos Wistar , Testosterona/sangue
16.
An Med Interna ; 25(1): 15-9, 2008 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-18377189

RESUMO

INTRODUCTION: Sleep disordered breathing and heart failure are common disorders that are frequently associated in the same patients which may bring on serious consequences. OBJECTIVE: To determine the prevalence of sleep apnea syndrome (SAS) in patients with controlled heart failure and the associated prevalence of arrhythmia. In addition, we to aim to evaluate the effectiveness of continuous positive airway pressure (CPAP) treatment for OSAS on left ventricular ejection fraction (EF). MATERIAL AND METHODS: We prospectively studied 60 patients (50 men, 10 women) with heart failure due to systolic dysfunction (left ventricular EF < 45%). All subjects were classified according the NYHA functional scale and received a specific questionnaire, as well as a home respiratory polygraphy and EKG Holter. A subject was considered to have SAS if their IAH > 15, and, according to standard recommendation, patients with IAH > 30 were treated with CPAP. After 3 months of treatment, the questionnaire, respiratory polygraphy and EKG Holter were repeated. RESULTS: Age was 69.3 +/- 10.4 years and the BMI was 28.5 +/- 4.74 kg/m2. Of the total sample, 55% (33 cases) were habitual snorers. The Epworth scale scores were 7.83 +/- 4.8. The EF was 36.3 +/- 7.4%, and 36 patients were NYHA class II, 23 were class III, and one patient was class IV. A total of 38 patients had SAS (63%): 14 (36%) had central sleep apnea and 24 (64%) had obstructive sleep apnea. EF revealed no significant differences between the SAS and non-SAS groups (36.42 +/- 7.6 vs. 35.81 +/- 6.6%, respectively). The SAS group presented a higher prevalence of bradicardia than the non-SAS group (24 % vs. 9%). After CPAP treatment, there was a significant improvement in EF (9%), in cases of obstructive sleep apnea, but no significant improvement was observed in patients with central sleep apnea. CONCLUSIONS: The prevalence of SAS in patients with heart failure due to systolic dysfunction is very high. CPAP treatment improved the EF in patients with obstructive sleep apnea.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Insuficiência Cardíaca/epidemiologia , Apneia do Sono Tipo Central/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/epidemiologia , Comorbidade , Eletrocardiografia Ambulatorial , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Apneia do Sono Tipo Central/terapia , Apneia Obstrutiva do Sono/terapia , Ronco , Volume Sistólico , Inquéritos e Questionários , Resultado do Tratamento
17.
Rev Gastroenterol Mex ; 73(1): 11-6, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-18792668

RESUMO

UNLABELLED: Esophageal cancer mortality is high and the incidence of this neoplasm is increasing. OBJECTIVE: Our aim was to compare the frequency of esophageal adenocarcinoma cases (EA) and squamous cell carcinoma (SCC) cases in two study periods (1977-1988 vs. 1989-2006). METHOD: Patients with esophageal cancer or adenocarcinoma of gastroesophageal junction (AGEJ) referred to the Nation al Institute of Medical Sciences and Nutrition "Salvador Zubirán" during 1989-2006 were included. The frequency of EA, SCC was compared with the previously reported series of our institute during 1977-1988. Risk factors for esophageal cancer and AGEJ were investigated. RESULTS: From 1989 to 2006 82 patients were studied, 23 with SCC, 29 with EA and 29 with AGEJ. There was a significant association between gastroesophageal reflux disease (GERD) and EA (OR = 9.5; CI 95% 1.9-48.5, P = 0.0025), and also between GERD and AGEJ (OR 5.6; CI 95% 1.07-28.8, P = 0.03). The association between Barrett's esophagus and EA (OR 14; CI 95% 1.65-119.2, P = 0.0035) and for GEJC (RM 13.6; IC 95% 1.6-116, P = 0.004) was significant. There was an increase in the frequency of AE from 11% (6/57) in the first period to 56% (29/52) in the second period (P < 0.001). The rela tion SCC/EA change from 7:1 in the first period to 0.8:1 in the second. CONCLUSION: There has been an increase in EA, being now the predominant hystologic type of esophageal cancer.


Assuntos
Adenocarcinoma/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Neoplasias Esofágicas/epidemiologia , Junção Esofagogástrica , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
18.
Carbohydr Polym ; 202: 409-417, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30287017

RESUMO

The study examines the use of macrobeads for the controlled-release of bacteria. Macrobeads were prepared by an easy dripping-technique using 20/80 wt/wt chitosan-starch blends and sodium tripolyphosphate as cross-linking agent. The resulting polymeric matrix was examined by SEM, XRD, TGA, and solid-RMN. The swelling-equilibrium, thermal behaviour, crystallinity, and size of macrobeads were affected by the autoclave-sterilization. The diameter of the sterilized xerogel was c.a. 1.6 mm. The results suggested that ionotropic-gelation and neutralization were the mechanisms underlying hydrogel formation. Plant growth-promoting bacteria (PGPB) were loaded into macrobeads separately or co-inoculated. Bacteria loaded macrobeads were dried and stored. Bacteria survived at least 12 months in orders of 109 CFU of A. brasilense/g and 108 CFU of P. fluorescens/g. Bacterial release in sterile saline solution tended to a super Case-II transport mechanism. Polymeric-matrix release efficiently both PGPB in natural soils, which uncovers their potential for the formulation of novel and improved biofertilizers.


Assuntos
Azospirillum brasilense/efeitos dos fármacos , Quitosana/farmacologia , Produtos Agrícolas/crescimento & desenvolvimento , Sistemas de Liberação de Medicamentos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Pseudomonas fluorescens/efeitos dos fármacos , Amido/farmacologia , Azospirillum brasilense/metabolismo , Quitosana/química , Produtos Agrícolas/microbiologia , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Tamanho da Partícula , Pseudomonas fluorescens/metabolismo , Amido/química
19.
Plant Physiol Biochem ; 132: 566-570, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30326435

RESUMO

The morphology and micromechanical properties of the mineral crystals embedded in the pecan nutshell (Carya illinoinensis) were characterized. Qualitative and quantitative morphological analyses carried out revealed that the crystals were comprised of calcium oxalate (CaOx) and have a wide range of sizes, with prismatic shapes, distributed heterogeneously in the sclerenchyma tissue. From indentation tests, it was found that CaOx crystals are stiffer structures compared to stone cells (sclerenchyma tissue), showing hardness and elastic modulus values of 0.53 ±â€¯0.19 GPa and 9.4 ±â€¯1.80 GPa, respectively. Additionally, the values of fracture toughness (0.08 ±â€¯0.02 MPa m0.5) and the brittleness index (9336 m-0.5) revealed that these types of structures are extremely brittle. The results obtained suggest that the main function of the CaOx crystals is to provide structural support to tissue. The presented methodology demonstrates the potential of the instrumented indentation technique (IIT) for in situ micromechanical characterization of mineral crystals located in plant tissues.


Assuntos
Oxalato de Cálcio/química , Carya/química , Fenômenos Biomecânicos , Carya/ultraestrutura , Cristalização , Minerais/química , Imagem Óptica
20.
Carbohydr Polym ; 196: 313-321, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29891301

RESUMO

Mango is an important crop worldwide, with a postharvest loss that is huge due to its climacteric behaviour. This study evaluated the softening of Tommy Atkins mangos during the ripening process. Ripening index (RPI) shown a decrease from 9.18 ±â€¯0.14 to 4.75 ±â€¯0.47. The enzymatic activity agreed with physicochemical parameters and with the structural and mechanical changes. Three pectin fractions were isolated from the mango cell wall: water soluble (WSP), chelator soluble (CSP) and diluted alkali soluble (DASP) pectin. The Younǵs modulus (E) of the primary cell wall was evaluated, it decreased from 1.69 ±â€¯1.02 to 0.39 ±â€¯0.16 MPa, which could be attributed to the softening of the fruit. A linear fit correlation between E and RPI was found. X-ray and confocal laser scanning microscopy analysis showed the changes occurred in the mango cell wall structure during maturation. Novelties of current study can be helpful in the use of mango wastes to obtain cellulose.

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