Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 157
Filter
1.
New Phytol ; 243(3): 1205-1219, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38855965

ABSTRACT

Decades of studies have demonstrated links between biodiversity and ecosystem functioning, yet the generality of the relationships and the underlying mechanisms remain unclear, especially for forest ecosystems. Using 11 tree-diversity experiments, we tested tree species richness-community productivity relationships and the role of arbuscular (AM) or ectomycorrhizal (ECM) fungal-associated tree species in these relationships. Tree species richness had a positive effect on community productivity across experiments, modified by the diversity of tree mycorrhizal associations. In communities with both AM and ECM trees, species richness showed positive effects on community productivity, which could have resulted from complementarity between AM and ECM trees. Moreover, both AM and ECM trees were more productive in mixed communities with both AM and ECM trees than in communities assembled by their own mycorrhizal type of trees. In communities containing only ECM trees, species richness had a significant positive effect on productivity, whereas species richness did not show any significant effects on productivity in communities containing only AM trees. Our study provides novel explanations for variations in diversity-productivity relationships by suggesting that tree-mycorrhiza interactions can shape productivity in mixed-species forest ecosystems.


Subject(s)
Biodiversity , Mycorrhizae , Trees , Mycorrhizae/physiology , Trees/microbiology , Species Specificity
2.
New Phytol ; 243(1): 132-144, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38742309

ABSTRACT

Nutrient limitation may constrain the ability of recovering and mature tropical forests to serve as a carbon sink. However, it is unclear to what extent trees can utilize nutrient acquisition strategies - especially root phosphatase enzymes and mycorrhizal symbioses - to overcome low nutrient availability across secondary succession. Using a large-scale, full factorial nitrogen and phosphorus fertilization experiment of 76 plots along a secondary successional gradient in lowland wet tropical forests of Panama, we tested the extent to which root phosphatase enzyme activity and mycorrhizal colonization are flexible, and if investment shifts over succession, reflective of changing nutrient limitation. We also conducted a meta-analysis to test how tropical trees adjust these strategies in response to nutrient additions and across succession. We find that tropical trees are dynamic, adjusting investment in strategies - particularly root phosphatase - in response to changing nutrient conditions through succession. These changes reflect a shift from strong nitrogen to weak phosphorus limitation over succession. Our meta-analysis findings were consistent with our field study; we found more predictable responses of root phosphatase than mycorrhizal colonization to nutrient availability. Our findings suggest that nutrient acquisition strategies respond to nutrient availability and demand in tropical forests, likely critical for alleviating nutrient limitation.


Subject(s)
Forests , Mycorrhizae , Nitrogen , Nutrients , Phosphorus , Trees , Tropical Climate , Phosphorus/metabolism , Nitrogen/metabolism , Mycorrhizae/physiology , Nutrients/metabolism , Plant Roots/metabolism , Plant Roots/microbiology , Phosphoric Monoester Hydrolases/metabolism , Panama
3.
Ecology ; 105(7): e4321, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38763891

ABSTRACT

Secondary tropical forests play an increasingly important role in carbon budgets and biodiversity conservation. Understanding successional trajectories is therefore imperative for guiding forest restoration and climate change mitigation efforts. Forest succession is driven by the demographic strategies-combinations of growth, mortality and recruitment rates-of the tree species in the community. However, our understanding of demographic diversity in tropical tree species stems almost exclusively from old-growth forests. Here, we assembled demographic information from repeated forest inventories along chronosequences in two wet (Costa Rica, Panama) and two dry (Mexico) Neotropical forests to assess whether the ranges of demographic strategies present in a community shift across succession. We calculated demographic rates for >500 tree species while controlling for canopy status to compare demographic diversity (i.e., the ranges of demographic strategies) in early successional (0-30 years), late successional (30-120 years) and old-growth forests using two-dimensional hypervolumes of pairs of demographic rates. Ranges of demographic strategies largely overlapped across successional stages, and early successional stages already covered the full spectrum of demographic strategies found in old-growth forests. An exception was a group of species characterized by exceptionally high mortality rates that was confined to early successional stages in the two wet forests. The range of demographic strategies did not expand with succession. Our results suggest that studies of long-term forest monitoring plots in old-growth forests, from which most of our current understanding of demographic strategies of tropical tree species is derived, are surprisingly representative of demographic diversity in general, but do not replace the need for further studies in secondary forests.


Subject(s)
Forests , Trees , Tropical Climate , Panama , Mexico , Costa Rica , Biodiversity
4.
Plant Sci ; 346: 112136, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38810884

ABSTRACT

Laticifers have been utilized as paradigms to enhance comprehension of specific facets of plant ecology and evolution. From the beginning of seedling growth, autonomous laticifer networks are formed throughout the plant structure, extending across all tissues and organs. The vast majority of identified products resulting from laticifer chemistry and metabolism are linked to plant defense. The latex, which is the fluid contained within laticifers, is maintained under pressure and has evolved to serve as a defense mechanism against both aggressors and invaders, irrespective of their capabilities or tactics. Remarkably, the latex composition varies among different species. The current goal is to understand the specific functions of various latex components in combating plant enemies. Therefore, the study of latex's chemical composition and proteome plays a critical role in advancing our understanding about plant defense mechanisms. Here, we will discuss some of these aspects.

5.
Diseases ; 12(5)2024 May 08.
Article in English | MEDLINE | ID: mdl-38785752

ABSTRACT

BACKGROUND: COVID-19 is an infectious disease characterized by a severe catabolic and inflammatory state, leading to loss of muscle mass. The assessment of muscle mass can be useful to identify nutritional risk and assist in early management, especially in older adults who have high nutritional risks. The aim of this study was to evaluate the association of calf circumference (CC) with clinical and biochemical markers and mortality in older adults with COVID-19 admitted to the intensive care unit (ICU). METHODS: A retrospective cross-sectional study was conducted in a public hospital. CC was adjusted for body mass index (BMI), reducing 3, 7, or 12 cm for a BMI of 25-29.9, 30-39.9, and ≥40 kg/m2, respectively, and classified as reduced when <33 cm for women and <34 cm for men. Pearson's correlation between BMI and CC was performed to assess the association between variables. Regression analysis was adjusted for sex, age, and BMI variables. Cox regression was used to assess survival related to CC. RESULTS: A total of 208 older adults diagnosed with COVID-19 admitted to ICU were included, of which 84% (n = 176) were classified as having reduced CC. These patients were older, with lower BMI, higher nutritional risk, malnourished, and higher concentration of urea and urea-creatinine ratio (UCR) compared with the group with normal CC. There was an association between edematous patients at nutritional risk and malnourished with reduced CC in the Cox regression, either adjusted or not for confounding. CONCLUSIONS: CC was not associated with severity, biochemical markers, or mortality in older adults with COVID-19 admitted to the ICU, but it was associated with moderately malnourished patients assessed by subjective global assessment (SGA).

6.
Belitung Nurs J ; 10(2): 134-142, 2024.
Article in English | MEDLINE | ID: mdl-38690302

ABSTRACT

Background: Nurses in adult care settings frequently encounter moral distress due to the daily ethical obligations they must fulfill. In contrast to other healthcare professionals, nurses often grapple with a heightened frequency of moral dilemmas, resulting in increased moral distress. Objective: This study aimed to explore the levels and relationship between moral caring competency and moral distress among Ghanaian nurses in adult care settings. Methods: This quantitative study utilized a descriptive-correlational design. A multistage sampling was used to select three public hospitals. Simple random sampling was used to recruit 231 nurses from the three public hospitals. Data were collected from June to July 2023 using validated questionnaires. The study utilized frequency and percentages, mean and standard deviation, and Spearman's Correlation. Results: The nurses had a low level of moral caring competency (M = 2.18, SD = 0.340). The composite moral distress score was 227.31, indicating a high level of moral distress among the nurses. Furthermore, there was a moderate, negative significant relationship between moral caring competency and moral distress (rs = -.474, N = 231, p <0.001). Conclusions: Nurses in public hospitals had limited personal cognitive, affective, and psychomotor abilities to address patient moral issues. The nurses also experience significant moral distress when delivering patient care. Furthermore, to decrease the level of moral distress, moral caring competency should be strengthened among nurses. Therefore, it is recommended that nurse administrators provide adequate organizational support and implement continuous moral training to improve nurses' moral caring competency and mitigate their moral distress. Healthcare policymakers are encouraged to develop or refine policies to navigate moral dilemmas and reduce moral distress among nurses. Future studies employing qualitative designs can explore the influence of culture on moral caring competency within the Ghanaian setting.

7.
RSC Adv ; 14(8): 5319-5330, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38344000

ABSTRACT

This work describes the synthesis of a novel material based on graphene oxide (GO) for the selective removal of boron in an aqueous medium. The material was obtained by functionalizing graphene oxide with N-methyl-d-glucamine (NMDG). This material, named NMDG@GO, was successfully characterized using Fourier-transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, atomic force microscopy, and elemental analysis. The adsorption process was studied from a kinetic perspective using pseudo-first-order and pseudo-second-order models, with the pseudo-second-order model presenting a better fit. The adsorption process was studied using Langmuir and Freundlich isotherms, with the Freundlich model providing a better fit and an r2 value of 0.9368. This result indicates that the adsorption process occurred in multilayers, considering a heterogeneous distribution of adsorption sites. The levels of the factor's adsorbent mass, pH, and time were optimized using a central composite design, with the optimal values achieved at 120 mg of material, pH = 2.0, and an agitation time of 40 min. Under these optimized conditions, it was possible to remove 22 to 35% of the boron present in saline waters from oil production (production and formation waters) using the developed adsorbent.

8.
Biol Rev Camb Philos Soc ; 99(3): 928-949, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38226776

ABSTRACT

The core principle shared by most theories and models of succession is that, following a major disturbance, plant-environment feedback dynamics drive a directional change in the plant community. The most commonly studied feedback loops are those in which the regrowth of the plant community causes changes to the abiotic (e.g. soil nutrients) or biotic (e.g. dispersers) environment, which differentially affect species availability or performance. This, in turn, leads to shifts in the species composition of the plant community. However, there are many other PE feedback loops that potentially drive succession, each of which can be considered a model of succession. While plant-environment feedback loops in principle generate predictable successional trajectories, succession is generally observed to be highly variable. Factors contributing to this variability are the stochastic processes involved in feedback dynamics, such as individual mortality and seed dispersal, and extrinsic causes of succession, which are not affected by changes in the plant community but do affect species performance or availability. Both can lead to variation in the identity of dominant species within communities. This, in turn, leads to further contingencies if these species differ in their effect on their environment (priority effects). Predictability and variability are thus intrinsically linked features of ecological succession. We present a new conceptual framework of ecological succession that integrates the propositions discussed above. This framework defines seven general causes: landscape context, disturbance and land-use, biotic factors, abiotic factors, species availability, species performance, and the plant community. When involved in a feedback loop, these general causes drive succession and when not, they are extrinsic causes that create variability in successional trajectories and dynamics. The proposed framework provides a guide for linking these general causes into causal pathways that represent specific models of succession. Our framework represents a systematic approach to identifying the main feedback processes and causes of variation at different successional stages. It can be used for systematic comparisons among study sites and along environmental gradients, to conceptualise studies, and to guide the formulation of research questions and design of field studies. Mapping an extensive field study onto our conceptual framework revealed that the pathways representing the study's empirical outcomes and conceptual model had important differences, underlining the need to move beyond the conceptual models that currently dominate in specific fields and to find ways to examine the importance of and interactions among alternative causal pathways of succession. To further this aim, we argue for integrating long-term studies across environmental and anthropogenic gradients, combined with controlled experiments and dynamic modelling.


Subject(s)
Ecosystem , Plants , Models, Biological , Plant Development/physiology
9.
Glob Chang Biol ; 30(1): e17140, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38273497

ABSTRACT

Growing evidence suggests that liana competition with trees is threatening the global carbon sink by slowing the recovery of forests following disturbance. A recent theory based on local and regional evidence further proposes that the competitive success of lianas over trees is driven by interactions between forest disturbance and climate. We present the first global assessment of liana-tree relative performance in response to forest disturbance and climate drivers. Using an unprecedented dataset, we analysed 651 vegetation samples representing 26,538 lianas and 82,802 trees from 556 unique locations worldwide, derived from 83 publications. Results show that lianas perform better relative to trees (increasing liana-to-tree ratio) when forests are disturbed, under warmer temperatures and lower precipitation and towards the tropical lowlands. We also found that lianas can be a critical factor hindering forest recovery in disturbed forests experiencing liana-favourable climates, as chronosequence data show that high competitive success of lianas over trees can persist for decades following disturbances, especially when the annual mean temperature exceeds 27.8°C, precipitation is less than 1614 mm and climatic water deficit is more than 829 mm. These findings reveal that degraded tropical forests with environmental conditions favouring lianas are disproportionately more vulnerable to liana dominance and thus can potentially stall succession, with important implications for the global carbon sink, and hence should be the highest priority to consider for restoration management.


Des preuves de plus en plus nombreuses suggèrent que la competition entre lianes et les arbres menace le puits de carbone mondial en ralentissant la récupération des forêts après une perturbation. Une théorie récente, fondée sur des observations locales et régionales, propose en outre que le succès compétitif des lianes sur les arbres est dû aux interactions entre la perturbation forestière et le climat. Nous présentons la première évaluation mondiale de la performance relative des lianes par rapport aux arbres en réponse aux perturbations forestières et aux facteurs climatiques. En utilisant un ensemble de données sans précédent, nous avons analysé 651 échantillons de végétation représentant 26,538 lianes et 82,802 arbres, issus de 556 emplacements uniques dans le monde entier, tirés de 83 publications. Les résultats montrent que les lianes ont de meilleure performances par rapport aux arbres (augmentation du ratio liane-arbre) lorsque les forêts sont perturbées, sous des zones chaudes aves précipitations faibles, et vers les basses altitudes tropicales. Nous avons également constaté que les lianes peuvent être un facteur critique entravant la récupération des forêts dans les forêts perturbées connaissant des climats favorables aux lianes, car les données de chronoséquence montrent que le succès compétitif élevé des lianes sur les arbres peut persister pendant des décennies après les perturbations, surtout lorsque la température annuelle moyenne dépasse 27.8°C, que les précipitations sont inférieures à 1614 mm et que le déficit hydrique climatique est supérieur à 829 mm. Ces découvertes révèlent que les forêts tropicales dégradées avec des conditions environnementales favorables aux lianes sont disproportionnellement plus vulnérables à la dominance des lianes, et peuvent ainsi potentiellement entraver la succession, avec d'importantes implications pour le puits de carbone mondial et devraient donc être la plus haute priorité à considérer pour la gestion de la restauration.


Subject(s)
Trees , Tropical Climate , Trees/physiology , Forests , Carbon Sequestration , Water
10.
Nat Commun ; 14(1): 8359, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38102119

ABSTRACT

Restoration of forests in low- and middle-income countries (LMICs) has the potential to contribute to international carbon mitigation targets. However, high upfront costs and variable cashflows are obstacles for many landholders. Carbon payments have been promoted as a mechanism to incentivize restoration and economists have suggested cost-sharing by third parties to reduce financial burdens of restoration. Yet empirical evidence to support this theory, based on robust, dynamic field sampling is lacking. Here we use large, long-term datasets from Panama to evaluate the financial prospects of three forest restoration methods under different cost-sharing and carbon payment designs where income is generated through timber harvests. We show some, but not all options are economically viable. Further work combining growth and survival data from field trials with more sophisticated financial analyses is essential to understanding barriers and realizing the potential of forest restoration in LMICs to help meet global carbon mitigation commitments.


Subject(s)
Carbon , Conservation of Natural Resources , Carbon/analysis , Forests , Panama , Ecosystem
11.
J Comp Pathol ; 205: 27-32, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37619448

ABSTRACT

A case of hepatic arteriovenous malformation is described in a calf that presented with a marked increase in abdominal volume and died 12 h after birth. At necropsy, the calf had marked abdominal distension and haemoperitoneum. The left hepatic lobe was reduced in size and covered by slightly whitish and intensely vascularized membranous tissue. At the edge of the left lobe there were cystic structures filled with translucent fluid. On cut surface, there were multiple cavitations well delimited by whitish walls and multiple dilated blood vessels that communicated with the cavitations. Histopathology revealed an increase in the number of vascular structures of variable calibre within loose fibrous connective tissue. The diagnosis of hepatic arteriovenous malformation was based on the lesions and confirmed by immunohistochemistry. Hepatic arteriovenous malformations are rare in all species, have not been described in cattle and should be included as a cause of mortality in neonates with post-partum haemoperitoneum.


Subject(s)
Arteriovenous Malformations , Cattle Diseases , Animals , Cattle , Arteriovenous Malformations/veterinary , Autopsy/veterinary , Hemoperitoneum/veterinary , Liver
13.
Food Chem ; 403: 134319, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36182849

ABSTRACT

Calotropis procera cysteine peptidases (CpCPs) have presented several potential biotechnological applications. Here, these enzymes were immobilized on glyoxyl-agarose (glyoxyl-CpCPs) with yields of 90-95 % and the recovered activities ranged from 10 % to 15 %, according to enzyme loadings (5, 10, 20, 40, and 50 mgBSAeq/g). Spectrophotometric assays and SDS-PAGE showed that the casein hydrolysis by glyoxyl-CpCPs was similar to soluble CpCPs. In addition, glyoxyl-CpCPs exhibited similar ratio of milk-clotting activity to proteolytic activity in comparison with soluble CpCPs and chymosin. Even after being stored for six months at 8 °C, the residual proteolytic activity of glyoxyl-CpCPs remained close to 100 %. Atomic force microscopy and dynamic light scattering techniques showed that the process of casein micelle aggregation after treatment with glyoxyl-CpCPs was very similar to its soluble form and chymosin. Glyoxyl-CpCPs performed well after five reaction cycles, producing cheeses with yield, moisture, protein, and fat similar to those produced with chymosin.


Subject(s)
Calotropis , Cysteine Proteases , Sepharose , Chymosin , Cysteine , Caseins , Cysteine Proteases/metabolism , Hydrogen-Ion Concentration , Enzymes, Immobilized/metabolism
14.
Matern Child Health J ; 26(11): 2293-2299, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36125671

ABSTRACT

STUDY OBJECTIVE: Different behaviors are considered important factors that may influence a healthy lifestyle. Given this fact, we aim to analyze the relationship between moderate-vigorous physical activity (MVPA), sleep time, and sedentary time, with cardiometabolic outcomes in adolescents. METHODS: Cross-sectional study, with 152 eutrophic and healthy adolescents. The behavioral variables were collected objectively and the arterial thickness was measured through ultrasound. Blood variables (LDL, TG, HDL, glucose, and insulin) were collected in a private laboratory. To analyze the data, the Student t test and Kruskal-Wallis test were used to compare the groups. All analyses adopted p < 0.05. RESULTS: Girls who demonstrated better combined behaviors, presented significant results for TG (p = 0.045), BP (p = 0.016), and cardiovascular score (p = 0.049) when compared to their peers. Furthermore, the practice of physical activity combined with sufficient sleep time was associated with lower values of arterial thickening (p = 0.017). CONCLUSIONS: In view of the results presented, it is possible to state that the aggregation of behaviors was more consistent in females and that the practice of physical activity and adequate sleep time can reflect on cardiovascular health.


Subject(s)
Exercise , Sedentary Behavior , Female , Adolescent , Humans , Pilot Projects , Cross-Sectional Studies , Sleep , Insulin , Glucose
15.
Talanta ; 250: 123718, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-35797860

ABSTRACT

Antifouling paints containing Cu, Zn, organotins, and many organic booster biocides may be found in ships and watercraft hulls to avoid the fouling of marine organisms. This type of paint can be harmful to the environment, therefore, the monitoring of toxic elements and compounds in antifouling paints are of great importance to access its quality and potential toxicity to the environment. Hence, this work describes the development of microwave-assisted digestion methods for the determination of Cu and Sn in antifouling paints by inductively coupled plasma optical emission spectrometry (ICP OES). The factors: sample mass and solutions of HNO3, HF, and HCl were optimized using the central composite design (CCD). Dry ashing with a muffle furnace and laser ablation-ICP-MS were used for methodological comparison with the microwave digestion-assisted ICP-OES methods. All the mixtures of acids allowed efficient extraction of the analytes; however, the one that stood out was the use of HF, HNO3, and H2O2.


Subject(s)
Biofouling , Disinfectants , Biofouling/prevention & control , Digestion , Hydrogen Peroxide , Microwaves , Paint , Spectrum Analysis
16.
Glob Chang Biol ; 28(17): 5254-5268, 2022 09.
Article in English | MEDLINE | ID: mdl-35703577

ABSTRACT

Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research-from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non-forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo includes data for 5163 species distributed across 1453 genera and 187 plant families. The database is publicly archived under a CC-BY 4.0 licence and can be access from: https://doi.org/10.5281/zenodo.6637599. To demonstrate its value, here we present three case studies that highlight how the Tallo database can be used to address a range of theoretical and applied questions in ecology-from testing the predictions of metabolic scaling theory, to exploring the limits of tree allometric plasticity along environmental gradients and modelling global variation in maximum attainable tree height. In doing so, we provide a key resource for field ecologists, remote sensing researchers and the modelling community working together to better understand the role that trees play in regulating the terrestrial carbon cycle.


Subject(s)
Forests , Trees , Biomass , Carbon/metabolism , Carbon Cycle , Ecosystem , Trees/physiology
17.
Ecol Appl ; 32(5): e2585, 2022 07.
Article in English | MEDLINE | ID: mdl-35333420

ABSTRACT

Predicting forest recovery at landscape scales will aid forest restoration efforts. The first step in successful forest recovery is tree recruitment. Forecasts of tree recruit abundance, derived from the landscape-scale distribution of seed sources (i.e., adult trees), could assist efforts to identify sites with high potential for natural regeneration. However, previous work revealed wide variation in the effect of seed sources on seedling abundance, from positive to no effect. We quantified the relationship between adult tree seed sources and tree recruits and predicted where natural recruitment would occur in a fragmented, tropical, agricultural landscape. We integrated species-specific tree crown maps generated from hyperspectral imagery and property ownership data with field data on the spatial distribution of tree recruits from five species. We then developed hierarchical Bayesian models to predict landscape-scale recruit abundance. Our models revealed that species-specific maps of tree crowns improved recruit abundance predictions. Conspecific crown area had a much stronger impact on recruitment abundance (8.00% increase in recruit abundance when conspecific tree density increases from zero to one tree; 95% credible interval (CI): 0.80% to 11.57%) than heterospecific crown area (0.03% increase with the addition of a single heterospecific tree, 95% CI: -0.60% to 0.68%). Individual property ownership was also an important predictor of recruit abundance: The best performing model had varying effects of conspecific and heterospecific crown area on recruit abundance, depending on individual property ownership. We demonstrate how novel remote sensing approaches and cadastral data can be used to generate high-resolution and landscape-level maps of tree recruit abundance. Spatial models parameterized with field, cadastral, and remote sensing data are poised to assist decision support for forest landscape restoration.


Subject(s)
Forests , Seeds , Bayes Theorem , Seedlings , Species Specificity , Tropical Climate
18.
Oral Dis ; 28(3): 786-795, 2022 Apr.
Article in English | MEDLINE | ID: mdl-33586328

ABSTRACT

BACKGROUND: Previous studies have shown that latex proteins from Plumeria pudica (LPPp) have anti-inflammatory and antioxidant activity. Therefore, the aim of this study was to evaluate the effects in rats of LPPp on ligature-induced periodontitis, an inflammatory disease. METHODS: The animals were divided into groups: saline (animals without induction of periodontitis), periodontitis (induced periodontitis and untreated) and LPPp (induced periodontitis and treated with 40 mg/kg). The following parameters were evaluated after 20 consecutive days of treatment: gingival bleeding index (GBI), probing pocket depth (PPD), alveolar bone height (ABH) and gingival myeloperoxidase (MPO) activity. In the hepatic tissue, malondialdehyde (MDA), glutathione (GSH) and histopathological alterations were evaluated. Blood levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. RESULTS: Significant reduction in GBI, PPD and gingival MPO activity and ABH was seen in animals treated with LPPp compared with periodontitis. Values of GSH, MDA, ALT and histopathological evaluation were preserved in animals treated with LPPp. CONCLUSIONS: Treatment with LPPp improved clinical aspects of periodontitis, reduced the blood and hepatic alterations and prevented alveolar bone loss. Data suggest that LPPp have potential for treatment of periodontitis.


Subject(s)
Alveolar Bone Loss , Apocynaceae , Periodontitis , Alveolar Bone Loss/drug therapy , Alveolar Bone Loss/etiology , Alveolar Bone Loss/prevention & control , Animals , Apocynaceae/metabolism , Latex/metabolism , Latex/pharmacology , Latex/therapeutic use , Periodontitis/drug therapy , Periodontitis/pathology , Rats , Rats, Wistar
19.
Food Chem ; 371: 131063, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34555703

ABSTRACT

This work aims the study chemometric methods for the classification of the origin of coffee samples. Samples of finely pulverized coffee grains were analyzed by synchronous molecular fluorescence spectroscopy to carry out the classification. The spectral data of the samples were obtained in triplicate in two offsets: 10 nm (with emission wavelengths from 240 nm to 600 nm) and 40 nm (from 240 nm to 560 nm), all with 1 nm resolution. Different strategies were performed using the spectra obtained with the offsets of 10 nm and 40 nm and fused data at mid-level (10 nm + 40 nm). The performances of linear and nonlinear methods were compared, the best results were obtained from the raw data from the fusion at low-level of the 10 nm and 40 nm offset spectra with the Pareto optimization criterion.


Subject(s)
Coffee , Geography , Spectrometry, Fluorescence
20.
Food Chem ; 373(Pt A): 131410, 2022 Mar 30.
Article in English | MEDLINE | ID: mdl-34710691

ABSTRACT

Antimicrobial peptides (AMPs) have been reported to be promising alternatives to chemical preservatives. Thus, this study aimed to characterise AMPs generated from the hydrolysis of wheat gluten proteins using latex peptidases of Calotropis procera, Cryptostegia grandiflora, and Carica papaya. The three hydrolysates (obtained after 16 h at 37 °C, using a 1: 25 enzyme:  substrate ratio) inhibited the growth of Aspergillus niger, A. chevalieri, Trichoderma reesei, Pythium oligandrum, Penicillium sp., and Lasiodiplodia sp. by 60-90%, and delayed fungal growth on bread by 3 days when used at 0.3 g/kg. Moreover, the specific volume and expansion factor of bread were not affected by the hydrolysates. Of 28 peptides identified, four were synthesised and exhibited activity against Penicillium sp. Fluorescence and scanning electron microscopy suggested that the peptides damaged the fungal plasma membrane. Bioinformatics analysis showed that no peptide was toxic and that the antigenic ones had cleavage sites for trypsin or pepsin.


Subject(s)
Calotropis , Latex , Antimicrobial Peptides , Aspergillus niger , Bread , Peptide Hydrolases , Peptides
SELECTION OF CITATIONS
SEARCH DETAIL
...