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1.
Int J Mol Sci ; 25(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612700

RESUMO

Drug hypersensitivity reactions (DHRs) to platinum-based compounds (PCs) are on the rise, and their personalized and safe management is essential to enable first-line treatment for these cancer patients. This study aimed to evaluate the usefulness of the basophil activation test by flow cytometry (BAT-FC) and the newly developed sIgE-microarray and BAT-microarray in diagnosing IgE-mediated hypersensitivity reactions to PCs. A total of 24 patients with DHRs to PCs (20 oxaliplatin and four carboplatin) were evaluated: thirteen patients were diagnosed as allergic with positive skin tests (STs) or drug provocation tests (DPTs), six patients were diagnosed as non-allergic with negative STs and DPTs, and five patients were classified as suspected allergic because DPTs could not be performed. In addition, four carboplatin-tolerant patients were included as controls. The BAT-FC was positive in 2 of 13 allergic patients, with a sensitivity of 15.4% and specificity of 100%. However, the sIgE- and BAT-microarray were positive in 11 of 13 DHR patients, giving a sensitivity of over 84.6% and a specificity of 90%. Except for one patient, all samples from the non-allergic and control groups were negative for sIgE- and BAT-microarray. Our experience indicated that the sIgE- and BAT-microarray could be helpful in the endophenotyping of IgE-mediated hypersensitivity reactions to PCs and may provide an advance in decision making for drug provocation testing.


Assuntos
Hipersensibilidade a Drogas , Hipersensibilidade Imediata , Poliquetos , Radiossensibilizantes , Tionas , Humanos , Animais , Teste de Degranulação de Basófilos , Compostos de Platina , Carboplatina/efeitos adversos , Hipersensibilidade a Drogas/diagnóstico , Antineoplásicos Alquilantes , Imunoglobulina E
2.
Photosynth Res ; 158(2): 151-169, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37515652

RESUMO

The Antarctic environment is extremely cold, windy and dry. Ozone depletion has resulted in increasing ultraviolet-B radiation, and increasing greenhouse gases and decreasing stratospheric ozone have altered Antarctica's climate. How do mosses thrive photosynthetically in this harsh environment? Antarctic mosses take advantage of microclimates where the combination of protection from wind, sufficient melt water, nutrients from seabirds and optimal sunlight provides both photosynthetic energy and sufficient warmth for efficient metabolism. The amount of sunlight presents a challenge: more light creates warmer canopies which are optimal for photosynthetic enzymes but can contain excess light energy that could damage the photochemical apparatus. Antarctic mosses thus exhibit strong photoprotective potential in the form of xanthophyll cycle pigments. Conversion to zeaxanthin is high when conditions are most extreme, especially when water content is low. Antarctic mosses also produce UV screening compounds which are maintained in cell walls in some species and appear to protect from DNA damage under elevated UV-B radiation. These plants thus survive in one of the harshest places on Earth by taking advantage of the best real estate to optimise their metabolism. But survival is precarious and it remains to be seen if these strategies will still work as the Antarctic climate changes.


Assuntos
Briófitas , Luz Solar , Regiões Antárticas , Raios Ultravioleta , Água
3.
J Med Food ; 26(6): 428-434, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37262194

RESUMO

Cinnamomum cassia is a medicinal plant whose use has demonstrated benefits on body weight, blood pressure, glucose, and lipids. This study aimed to evaluate the effect of C. cassia on arterial stiffness and endothelial dysfunction (ED) in patients with type 2 diabetes mellitus (T2DM). A randomized, double-blind, placebo-controlled clinical trial was carried out in 18 subjects aged 40-65 years, with a diagnosis of T2DM of one year or less since diagnosis and treated with Metformin 850 mg daily. Patients were randomly assigned to receive either C. cassia or a placebo in 1000 mg capsules, thrice a day, before each meal for 12 weeks. At baseline and after 12 weeks of intervention, brachial-ankle pulse wave velocity and Flow Mediated Dilation were measured, as well as body weight, body mass index (BMI), blood pressure (BP), fasting glucose (FG), glycated hemoglobin A1c (HbA1c), total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, and very low density lipoprotein cholesterol, respectively, triglycerides, creatinine, and transaminases. The Mann-Whitney U test for differences between groups and the Wilcoxon signed-rank test for intragroup differences were used, and a P ≤ .05 was considered statistically significant. After C. cassia administration, statistically significant reductions in body weight (81.4 ± 10.4 kg vs. 79.9 ± 9.0 kg, P = .037), BMI (30.6 ± 4.2 kg/m2 vs. 30.1 ± 4.2 kg/m2, P = .018), and HbA1c (53 ± 5.4 mmol/mol vs. 45 ± 2.1 mmol/mol, P = .036) were observed. No changes statistically significant on arterial stiffness, ED, FG, BP, and lipids were observed. C. cassia administration decreases body weight, BMI, and HbA1c without statistically significant changes on arterial stiffness, ED, FG, BP, and lipids. CTR Number: NCT04259606.


Assuntos
Cinnamomum aromaticum , Diabetes Mellitus Tipo 2 , Rigidez Vascular , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Índice Tornozelo-Braço , Análise de Onda de Pulso , Triglicerídeos , Glucose , Peso Corporal
4.
Ecol Lett ; 26(4): 549-562, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36750322

RESUMO

In recent years, attempts have been made in linking pressure-volume parameters and the leaf economics spectrum to expand our knowledge of the interrelationships among leaf traits. We provide theoretical and empirical evidence for the coordination of the turgor loss point and associated traits with net CO2 assimilation (An ) and leaf mass per area (LMA). We measured gas exchange, pressure-volume curves and leaf structure in 45 ferns and angiosperms, and explored the anatomical and chemical basis of the key traits. We propose that the coordination observed between mass-based An , capacitance and the turgor loss point (πtlp ) emerges from their shared link with leaf density (one of the components of LMA) and, specially, leaf saturated water content (LSWC), which in turn relates to cell size and nitrogen and carbon content. Thus, considering the components of LMA and LSWC in ecophysiological studies can provide a broader perspective on leaf structure and function.


Assuntos
Magnoliopsida , Folhas de Planta , Folhas de Planta/fisiologia , Fotossíntese , Nitrogênio , Carbono
5.
Planta ; 257(2): 29, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36592261

RESUMO

MAIN CONCLUSION: ETR/AN ratios should be in the range 7.5-10.5 for non-stressed C3 plants. Ratios extremely out of this range can be reflecting both uncontrolled plant status and technical mistakes during measurements. We urge users to explicitly refer to this ratio in future studies as a proof for internal data quality control. For the last few decades, the use of infra-red gas-exchange analysers (IRGAs) coupled with chlorophyll fluorometers that allow for measurements of net CO2 assimilation rate and estimates of electron transport rate over the same leaf area has been popularized. The evaluation of data from both instruments in an integrative manner can result in additional valuable information, such as the estimation of the light respiration, mesophyll conductance and the partitioning of the flux of electrons into carboxylation, oxygenation and alternative processes, among others. In this review, an additional and more 'straight' use of the combination of chlorophyll fluorescence and gas exchange-derived parameters is presented, namely using the direct ratio between two fully independently estimated parameters, electron transport rate (ETR)-determined by the fluorometer-and net CO2 assimilation rate (AN)-determined by the IRGA, i.e., the ETR/AN ratio, as a tool for fast detection of incongruencies in the data and potential technical problems associated with them, while checking for the study plant's status. To illustrate this application, a compilation of 75 studies that reported both parameters for a total of 178 species under varying physiological status is presented. Values of ETR/AN between 7.5 and 10.5 were most frequently found for non-stressed C3 plants. C4 species showed an average ETR/AN ratio of 4.7. The observed ratios were larger for species with high leaf mass per area and for plants subjected to stressful factors like drought or nutritional deficit. Knowing the expected ETR/AN ratio projects this ratio as a routinary and rapid check point for guaranteeing both the correct performance of equipment and the optimal/stress status of studied plants. All known errors associated with the under- or overestimation of ETR or AN are summarized in a checklist that aims to be routinely used by any IRGA/fluorometer user to strength the validity of their data.


Assuntos
Dióxido de Carbono , Fotossíntese , Transporte de Elétrons , Fotossíntese/fisiologia , Plantas , Clorofila , Folhas de Planta/fisiologia
6.
Food Chem ; 400: 134046, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36067696

RESUMO

Psidium guajava L. and Psidium friedrichsthalianum Nied are part of the Psidium species native to America. Nowadays, it is essential to study the phenolic compound (PC) profile and their changes during digestion and the fractions available for absorption. This study aimed to characterize the PC profile in some Psidium species and their bioaccessibility (BA). Fifty-seven compounds were identified, and forty-six belonged to ten different phenolic classes. PC profiles showed significant differences between the species and the intestinal fraction P. friedrichsthalianum Nied. showed the highest PC content, although it mostly belonged to non-extractable polyphenols. This leads to the lowest BA (37%); P. guajava L. 'Morada' showed the highest (47%). Hydroxycinnamic acids were the most stable PC after gastrointestinal digestion. This study showed relevant differences in the PC content and profile of different Psidium species and changes between the PC in the original matrix and those released in the different stages of gastrointestinal digestion.


Assuntos
Psidium , Ácidos Cumáricos , Digestão , Fenóis , Extratos Vegetais
8.
J Exp Bot ; 73(13): 4592-4604, 2022 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-35524766

RESUMO

Bryophytes are the group of land plants with the lowest photosynthetic rates, which was considered to be a consequence of their higher anatomical CO2 diffusional limitation compared with tracheophytes. However, the most recent studies assessing limitations due to biochemistry and mesophyll conductance in bryophytes reveal discrepancies based on the methodology used. In this study, we compared data calculated from two different methodologies for estimating mesophyll conductance: variable J and the curve-fitting method. Although correlated, mesophyll conductance estimated by the curve-fitting method was on average 4-fold higher than the conductance obtained by the variable J method; a large enough difference to account for the scale of differences previously shown between the biochemical and diffusional limitations to photosynthesis. Biochemical limitations were predominant when the curve-fitting method was used. We also demonstrated that variations in bryophyte relative water content during measurements can also introduce errors in the estimation of mesophyll conductance, especially for samples which are overly desiccated. Furthermore, total chlorophyll concentration and soluble proteins were significantly lower in bryophytes than in tracheophytes, and the percentage of proteins quantified as Rubisco was also significantly lower in bryophytes (<6.3% in all studied species) than in angiosperms (>16% in all non-stressed cases). Photosynthetic rates normalized by Rubisco were not significantly different between bryophytes and angiosperms. Our data suggest that the biochemical limitation to photosynthesis in bryophytes is more relevant than so far assumed.


Assuntos
Briófitas , Magnoliopsida , Briófitas/metabolismo , Dióxido de Carbono/metabolismo , Clorofila/metabolismo , Magnoliopsida/metabolismo , Células do Mesofilo/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo
9.
Food Chem X ; 13: 100195, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35499004

RESUMO

Gut microbiota is a complex ecosystem of symbiotic bacteria that contribute to human metabolism and supply intestinal metabolites, whose production is mainly influenced by the diet. Dietary patterns characterized by a high intake of protein promotes the growth of proteolytic bacteria's, which produce metabolites from undigested protein fermentation. Microbioal protein metabolites can regulate immune, metabolic and neuronal responses in different target organs. Metabolic pathways of these compounds and their mechanisms of action on different pathologies can lead to the discovery of new diagnostic techniques, drugs and the potential use as functional ingredients in food. This review discusses the potential mechanisms by which amino acid catabolism is involved in microbial protein metabolites. In addition, results from several studies on the association of products from the intestinal metabolism of indigestible proteins and the state of health or disease of the host are revised.

10.
J Exp Bot ; 73(13): 4562-4575, 2022 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-35298628

RESUMO

The data available so far indicate that the photosynthetic and relative growth rates of bryophytes are 10% of those reported for tracheophytes. By examining the existing literature and reanalysing data published in over 100 studies, this review examines the ecophysiological, biochemical, and structural reasons behind this phenomenon. The limiting Rubisco content and surface for gas exchange are the internal factors that can explain the low photosynthetic and growth rates of bryophytes. The role of the thicker cell walls of bryophytes in limiting CO2 diffusion is unclear, due to the current uncertainties regarding their porosity and permeability to CO2. From this review, it is also evident that, despite bryophytes having low photosynthetic rates, their positive carbon balance is tightly related to their capacity to deal with extreme conditions. Contributing factors include their capacity to deal with large daily temperature oscillations, and their capacity to delay the cessation of photosynthesis under water deficit (or to tolerate desiccation in extreme situations). Although further studies on bryophytes are needed before more solid conclusions can be drawn, it seems that their success relies on their remarkable tolerance to a highly variable environment, possibly at the expense of their maximum photosynthetic rate.


Assuntos
Briófitas , Carbono , Briófitas/metabolismo , Dióxido de Carbono , Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo
11.
Physiol Plant ; 174(2): e13661, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35249226

RESUMO

Mosses have been found outliers of the trade-off between photosynthesis and bulk elastic modulus described for vascular plants. Hence, potential trade-offs among physical features of cell walls and desiccation tolerance, water relations, and photosynthesis were assessed in bryophytes and other poikilohydric species. Long-term desiccation tolerance was quantified after variable periods of desiccation/rehydration cycles. Water relations were analyzed by pressure-volume curves. Mesophyll conductance was estimated using both CO2 curve-fitting and anatomical methods. Cell wall elasticity was the parameter that better correlated with the desiccation tolerance index for desiccation tolerant species and was antagonistic to higher absolute values of osmotic potential. Although high values of cell wall effective porosity were estimated compared with the values assumed for vascular plants, the desiccation tolerance index negatively correlated with the porosity in desiccation tolerant bryophytes. Neither cell wall thickness nor photosynthetic capacity were correlated with the desiccation tolerance index of the studied species. The existence of a potential evolutionary trade-off between cell wall thickness and desiccation tolerance is rejected. The photosynthetic capacity reported for bryophytes is independent of elasticity and desiccation tolerance. Furthermore, the role of cell wall thickness in limiting CO2 conductance would be overestimated under a scenario of high cell wall porosity for most bryophytes.


Assuntos
Briófitas , Dióxido de Carbono , Dióxido de Carbono/metabolismo , Parede Celular/metabolismo , Dessecação , Elasticidade , Fotossíntese , Água/metabolismo
12.
Plant Foods Hum Nutr ; 77(1): 77-82, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35020097

RESUMO

To the best of our knowledge, "sweet mini bell" peppers have not been extensively investigated. In this study, we evaluated the bioaccessible phenolic compounds released during intestinal digestion and identified and quantified the microbial metabolites derived from phenolic compounds bioconversion during the in vitro colonic fermentation. A total of 66 phenolic compounds were determined. The results obtained in this study indicate that hydroxycinnamic acids (22 to 32 mg/100 g dw) and flavonoids (99 to 102 mg/100 g dw) headed by quercetin, luteolin and kaempferol glycosidic derivatives were the main bioaccessible phenolic compounds during in vitro intestinal digestion of mini bell peppers. The yellow variety contained the highest concentration of bioaccessible flavonoids (80 mg/100 g dw). For the first time in mini bell peppers, dihydroferulic acid was detected, in the three varieties studied. 3-(4-hydroxyphenyl)propionic acid was the major metabolite found after 12-24 h fermentation of all samples (44 to 102 µM/L). Further cell culture or in vivo studies are needed to elucidate the biological activities of the phenolic compounds identified in mini bell peppers.


Assuntos
Capsicum , Polifenóis , Biotransformação , Colo , Flavonoides/metabolismo , Fenóis/metabolismo , Polifenóis/metabolismo
13.
Dalton Trans ; 50(46): 17062-17074, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34779462

RESUMO

Aurivillius compounds with the general formula (Bi2O2)(An-1BnO3n+1) are a highly topical family of functional layered oxides currently under investigation for room-temperature multiferroism. A chemical design strategy is the incorporation of magnetically active BiMO3 units (M: Fe3+, Mn3+, Co3+ …) into the pseudo-perovskite layer of known ferroelectrics like Bi4Ti3O12, introducing additional oxygen octahedra. Alternatively, one can try to directly substitute magnetic species for Ti4+ in the perovskite slab. Previous reports explored the introduction of the M3+ species, which required the simultaneous incorporation of a 5+ cation, as for the Bi4Ti3-2xNbxFexO12 system. A larger magnetic fraction might be attained if Ti4+ is substituted with Mn4+, though it has been argued that the small ionic radius prevents its incorporation into the pseudo-perovskite layer. We report here the mechanosynthesis of Aurivillius Bi4Ti2-xMnxNb0.5Fe0.5O12 (n = 3) compounds with increasing Mn4+ content up to x = 0.5, which corresponds to a magnetic fraction of 1/3 at the B-site surpassing the threshold for percolation, and equal amounts of Mn4+ and Fe3+. The appearance of ferromagnetic superexchange interactions and magnetic ordering was anticipated and is shown for phases with x ≥ 0.3. Ceramic processing was accomplished by spark plasma sintering, which enabled electrical measurements that demonstrated ferroelectricity for all Mn4+-containing Aurivillius compounds. This is a new family of layered oxides and a promising alternative single-phase approach for multiferroism.

14.
JMIR Mhealth Uhealth ; 9(5): e26442, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34032576

RESUMO

BACKGROUND: Poor medication adherence is a major challenge in asthma, and objective assessment of inhaler adherence is needed. The InspirerMundi app aims to monitor adherence while providing a positive experience through gamification and social support. OBJECTIVE: This study aimed to evaluate the feasibility and acceptability of the InspirerMundi app to monitor medication adherence in adolescents and adults with persistent asthma (treated with daily inhaled medication). METHODS: A 1-month mixed method multicenter observational study was conducted in 26 secondary care centers from Portugal and Spain. During an initial face-to-face visit, physicians reported patients' asthma therapeutic plan in a structured questionnaire. During the visits, patients were invited to use the app daily to register their asthma medication intakes. A scheduled intake was considered taken when patients registered the intake (inhaler, blister, or other drug formulation) by using the image-based medication detection tool. At 1 month, patients were interviewed by phone, and app satisfaction was assessed on a 1 (low) to 5 (high) scale. Patients were also asked to point out the most and least preferred app features and make suggestions for future app improvements. RESULTS: A total of 107 patients (median 27 [P25-P75 14-40] years) were invited, 92.5% (99/107) installed the app, and 73.8% (79/107) completed the 1-month interview. Patients interacted with the app a median of 9 (P25-P75 1-24) days. At least one medication was registered in the app by 78% (77/99) of patients. A total of 53% (52/99) of participants registered all prescribed inhalers, and 34% (34/99) registered the complete asthma therapeutic plan. Median medication adherence was 75% (P25-P75 25%-90%) for inhalers and 82% (P25-P75 50%-94%) for other drug formulations. Patients were globally satisfied with the app, with 75% (59/79) scoring ≥4,; adherence monitoring, symptom monitoring, and gamification features being the most highly scored components; and the medication detection tool among the lowest scored. A total of 53% (42/79) of the patients stated that the app had motivated them to improve adherence to inhaled medication and 77% (61/79) would recommend the app to other patients. Patient feedback was reflected in 4 major themes: medication-related features (67/79, 85%), gamification and social network (33/79, 42%), symptom monitoring and physician communication (21/79, 27%), and other aspects (16/79, 20%). CONCLUSIONS: The InspirerMundi app was feasible and acceptable to monitor medication adherence in patients with asthma. Based on patient feedback and to increase the registering of medications, the therapeutic plan registration and medication detection tool were redesigned. Our results highlight the importance of patient participation to produce a patient-centered and engaging mHealth asthma app.


Assuntos
Asma , Aplicativos Móveis , Adolescente , Adulto , Asma/tratamento farmacológico , Estudos de Viabilidade , Humanos , Adesão à Medicação , Espanha
15.
New Phytol ; 231(4): 1415-1430, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33959976

RESUMO

Desiccation tolerant plants can survive extreme water loss in their vegetative tissues. The fern Anemia caffrorum produces desiccation tolerant (DT) fronds in the dry season and desiccation sensitive (DS) fronds in the wet season, providing a unique opportunity to explore the physiological mechanisms associated with desiccation tolerance. Anemia caffrorum plants with either DT or DS fronds were acclimated in growth chambers. Photosynthesis, frond structure and anatomy, water relations and minimum conductance to water vapour were measured under well-watered conditions. Photosynthesis, hydraulics, frond pigments, antioxidants and abscisic acid contents were monitored under water deficit. A comparison between DT and DS fronds under well-watered conditions showed that the former presented higher leaf mass per area, minimum conductance, tissue elasticity and lower CO2 assimilation. Water deficit resulted in a similar induction of abscisic acid in both frond types, but DT fronds maintained higher stomatal conductance and upregulated more prominently lipophilic antioxidants. The seasonal alternation in production of DT and DS fronds in A. caffrorum represents a mechanism by which carbon gain can be maximized during the rainy season, and a greater investment in protective mechanisms occurs during the hot dry season, enabling the exploitation of episodic water availability.


Assuntos
Anemia , Gleiquênias , Desidratação , Dessecação , Fotossíntese , Folhas de Planta , Água
16.
Food Chem ; 360: 130051, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34020365

RESUMO

Two of the most important Mexican plant-foods are tomato (Solanum lycopersicum L.) and husk tomato (Physalis ixocarpa Brot.). In this study three objectives were followed: i) to evaluate the bioaccessible phenolic compounds (PC) in T and HT during upper gastrointestinal digestion, ii) to in vitro ferment the indigestible fractions of the samples to evaluate the short-chain fatty acids (SCFA) production, iii) the microbial metabolites, bioconverted PC and volatile organic compounds (VOCs) generated during the fermentation. Vanillic acid was the most bioaccessible PC and after 48 h, 3-hydroxyphenylacetic acid was the most abundant microbial metabolite identified in both samples. The identification of VOCs belonging to terpenes (and derivatives) group in T and HT can be product of the microbial metabolism of carotenoids. The study shows new knowledge of the in vitro intestinal digestion and fermentation of T and HT final compounds with biological potential which should be evaluated in further studies.


Assuntos
Colo/microbiologia , Ácidos Graxos Voláteis/metabolismo , Fermentação , Frutas/química , Microbioma Gastrointestinal , Fenóis/metabolismo , Disponibilidade Biológica , Carotenoides/metabolismo , Digestão , Solanum lycopersicum , Fenilacetatos/metabolismo , Physalis , Ácido Vanílico/metabolismo , Compostos Orgânicos Voláteis/metabolismo
17.
J Exp Bot ; 72(11): 3971-3986, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33780533

RESUMO

The key role of cell walls in setting mesophyll conductance to CO2 (gm) and, consequently, photosynthesis is reviewed. First, the theoretical properties of cell walls that can affect gm are presented. Then, we focus on cell wall thickness (Tcw) reviewing empirical evidence showing that Tcw varies strongly among species and phylogenetic groups in a way that correlates with gm and photosynthesis; that is, the thicker the mesophyll cell walls, the lower the gm and photosynthesis. Potential interplays of gm, Tcw, dehydration tolerance, and hydraulic properties of leaves are also discussed. Dynamic variations of Tcw in response to the environment and their implications in the regulation of photosynthesis are discussed, and recent evidence suggesting an influence of cell wall composition on gm is presented. We then propose a hypothetical mechanism for the influence of cell walls on photosynthesis, combining the effects of thickness and composition, particularly pectins. Finally, we discuss the prospects for using biotechnology for enhancing photosynthesis by altering cell wall-related genes.


Assuntos
Dióxido de Carbono , Fotossíntese , Dióxido de Carbono/metabolismo , Parede Celular/metabolismo , Células do Mesofilo , Filogenia , Folhas de Planta
18.
J Exp Bot ; 72(7): 2600-2610, 2021 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-33483750

RESUMO

Resurrection plants are vascular species able to sustain extreme desiccation in their vegetative tissues. Despite its potential interest, the role of leaf anatomy in CO2 diffusion and photosynthesis under non-stressed conditions has not been explored in these species. Net CO2 assimilation (An) and its underlying diffusive, biochemical, and anatomical determinants were assessed in 10 resurrection species from diverse locations, including ferns, and homoiochlorophyllous and poikilochlorophyllous angiosperms. Data obtained were compared with previously published results in desiccation-sensitive ferns and angiosperms. An in resurrection plants was mostly driven by mesophyll conductance to CO2 (gm) and limited by CO2 diffusion. Resurrection species had a greater cell wall thickness (Tcw) than desiccation-sensitive plants, a feature associated with limited CO2 diffusion in the mesophyll, but also greater chloroplast exposure to intercellular spaces (Sc), which usually leads to higher gm. This combination enabled a higher An per Tcw compared with desiccation-sensitive species. Resurrection species possess unusual anatomical features that could confer stress tolerance (thick cell walls) without compromising the photosynthetic capacity (high chloroplast exposure). This mechanism is particularly successful in resurrection ferns, which display higher photosynthesis than their desiccation-sensitive counterparts.


Assuntos
Craterostigma , Dióxido de Carbono/metabolismo , Parede Celular , Cloroplastos/metabolismo , Células do Mesofilo , Fotossíntese , Folhas de Planta
19.
Food Res Int ; 139: 109917, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33509484

RESUMO

Husk tomato (Physalis ixocarpa Brot. ex. Horm) is mainly used in the preparation of many Mexican sauces due to its unique and slightly acidic flavor, both in raw and cooked forms. These sauces also usually contain Serrano hot pepper (Capsicum annuum L), onion (Allium cepa L.), garlic (Allium sativum L.), coriander (Coriandrum sativum L.) and salt. Mexican sauces are a pre-Hispanic staple food, yet there is scarce knowledge on the phenolic compounds (PC) that reach the colon bound to the indigestible fraction (IF) after intestinal digestion. Thus, the aim of the present work was to evaluate the indigestible fraction of two types of Mexican sauces made with cooked and raw husk tomato: cooked green sauce (CGS) and raw green sauce (RGS). IF of CGS and RGS were fermented in the in vitro model of the human colon (TIM-2) to investigate the PC bioconversion by the gut microbiota after 24, 48 and 72 h. PC of the original sauces and their predigested fractions, as well as the formed metabolites were identified and monitored by HPLC-ESI-QToF-MS. Cooking husk tomato significantly increased the total indigestible fraction (TIF), mainly due to its insoluble indigestible fraction (IIF), and diminished PC. Flavonoids (flavonols and flavones) were the most abundant phenolic group in digested sauces followed by capsaicinoids (a characteristic group derived from hot pepper), hydroxycinnamic acids, and hydroxybenzoic acids. The metabolites 3-(ρ-hydroxyphenyl) propionic acid, 3-(3-hydroxyphenyl) propionic acid and 4-hydroxyphenylacetic acid were the most abundant colonic metabolites identified, which are thought to be derived from the biotransformation of flavonoids and hydroxycinnamates. These results are the first obtained on in vitro colonic fermentation of Mexican sauces and should be considered in future studies on the health effects related to consuming this staple food.


Assuntos
Colo , Microbioma Gastrointestinal , Colo/metabolismo , Fermentação , Flavonoides/metabolismo , Humanos , Paladar
20.
Front Allergy ; 2: 787537, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35387052

RESUMO

The increased use of antineoplastic drugs has been associated with a rising number of hypersensitivity reactions to these drugs, which has led to a growth in the demand for assistance from allergy services. The involvement of an allergist is essential to ensure that these patients with hypersensitivity reactions continue to be able to receive appropriate first-line treatment. Chemotherapy and biological agents have specific handling requirements and all the allergy departments involved in the diagnosis and therapeutic management of patients reacting to these drugs should find the means to guarantee safety. There are currently several guidelines on the safe handling of hazardous drugs for healthcare workers. However, specific recommendations are lacking for reducing occupational exposure in staff working in the allergy departments and managing these drugs for the diagnosis and management of hypersensitivity reactions. This review article focuses on the safe handling strategy of the allergy department in the Ramón y Cajal University Hospital and provides details of its implementation and experience over 10 years. This protocol could improve the knowledge of safe handling of antineoplastic drugs in allergy procedures.

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