Regulation of Rubisco activity in crops.

Efficient plant acclimation to changing environmental conditions relies on fast adjustments of the transcriptome, proteome, and metabolome. Regulation of enzyme activity depends on the activity of specific chaperones, chemical post-translational modifications (PTMs) of amino acid residues, and changes in the cellular and organellar microenvironment. Central to carbon assimilation, and thus plant growth and yield, Rubisco activity is regulated by its chaperone Rubisco activase (Rca) and by adjustments in the chloroplast stroma environment. Focused on crops, this review highlights the main PTMs and stromal ions and metabolites affecting Rubisco and Rca in response to environmental stimuli. Rca isoforms differ in regulatory properties and heat sensitivity, with expression changing according to the surrounding environment. Much of the physiological relevance of Rubisco and Rca PTMs is still poorly understood, though some PTMs have been associated with Rubisco regulation in response to stress. Ion and metabolite concentrations in the chloroplast change in response to variations in light and temperature. Some of these changes promote Rubisco activation while others inhibit activation, deactivate the enzyme, or change the rates of catalysis. Understanding these regulatory mechanisms will aid the development of strategies to improve carbon fixation by Rubisco under rapidly changing environments as experienced by crop plants.

Effects of a respiratory and neurological rehabilitation treatment plan in post Covid-19 affected university students. Randomized clinical study.

BACKGROUND: COVID-19 demonstrated the possibility of neurological complications such as loss of sense of smell and taste, together with respiratory problems. Respiratory training and rehabilitation of neurological sequelae are essential to improve respiratory function and thus quality of life, and the aim of this study is to evaluate the efficacy of a pulmonary and neurological rehabilitation program. OBJECTIVES: To apply a treatment to reduce dyspnea, increase exertional capacity, increase vital capacity and respiratory muscle strength, together with an increase in olfactory and gustatory sensitivity in post-SARS-CoV-2 patients. METHODS: A randomised controlled experimental study was conducted in 220 patients with a medical diagnosis of COVID-19 and more than 5 months of evolution, dyspnoea or perceived fatigue, including olfactory and gustatory perception problems, of whom 200 patients completed the study. 100 patients were randomly assigned to the intervention group, consisting of an inspiratory training treatment plan (Powerbreathe Plus®) combined with aerobic exercise and olfactory gustatory treatment for 31 days, and 100 patients to the control group, for 31 days without any type of therapy. RESULTS: The study was conducted in post-Covid-19 patients for 5 months. Two hundred patients were divided into an intervention group (n = 100) and a control group (n = 100). The comparison between the groups showed significant differences in spirometric variables; forced vital capacity (p < .001; Eta2 (0.439); Mean: 0,6135), the ratio between both FEV1/FVC (p < 0.01; Eta2 (0.728); Mean:9,313), peak inspiratory pressure (p < 0.01; Eta2 (0.906); Mean:4,526); changes were observed in dyspnoea measured with the modified Borg scale (p < 0.01; Eta2 (0.811); Mean:1,481) and the modified Medical Research Council scale (p < 0.01; Eta2 (0.881); Mean: 0.777); finally, changes were found in neurological variables, in the questions of the Singapore Smell and Taste Questionnaire, How was your sense of smell after treatment? (p < 0.01; Eta2 (0.813); Mean: 1,721) and How is your sense of taste after treatment? (p < 0.01; Eta2 (0.898); Mean: 1,088). CONCLUSION: The implementation of a respiratory rehabilitation treatment plan with the Powerbreathe Plus® device, aerobic exercise and neurorehabilitation with olfactory and gustatory training, is a therapeutic option against respiratory and neurological sequelae in patients who have suffered such sequelae due to the SARS-CoV-2 virus. Clinicaltrials.gov: NCT05195099. First posted 18/01/2022; Last Update Posted 29/06/2022.

Barriers to employing digital technologies for a circular economy: A multi-level perspective.

Industry 4.0 and digital technologies might significantly impact resource optimization in a smart circular economy. However, adopting digital technologies is not easy due to barriers that may arise during this process. While prior literature offers initial insights into barriers at the firm level, these studies pay less attention to these barriers' multi-level nature. Focusing only on one particular level while ignoring others may not unleash the full potential of DTs in a circular economy. To overcome barriers, it's necessary to have a systemic understanding of the phenomenon, which is missing in previous literature. By combining a systematic literature review and multiple case studies of nine firms, this study aims to unpack the multi-level nature of barriers to a smart circular economy. The primary contribution of this study is a new theoretical framework composed of eight dimensions of barriers. Each dimension provides unique insights related to the multi-level nature of the smart circular economy transition. In total, 45 barriers were identified and categorized into the following dimensions: 1. Knowledge management (five barriers), 2. Financial (three barriers), 3. Process management & Governance (eight barriers), 4. Technological (ten barriers), 5. Product & Material (three barriers), 6. Reverse logistic infrastructure (four barriers), 7. Social behaviour (seven barriers), and 8. Policy & Regulatory (five barriers). This study examines how each dimension and multi-level barrier affects the transitions toward a smart circular economy. An effective transition copes with complex, multidimensional, multi-level barriers, which might require mobilization beyond a single firm. Government actions need to be more effective and correlated with sustainable initiatives. Policies also should focus on mitigating barriers. Overall, the study contributes to smart circular economy literature by increasing theoretical and empirical understanding of digital transformation barriers towards circularity.

Pediatric erythema multiforme induced by topical imiquimod: a case report.

Erythema multiforme (EM) is a rare immune-mediated reaction with mucocutaneous involvement. This case report describes the development of EM in a 9-year-old girl after treatment with imiquimod, a topical immunomodulator used in the management of some dermatologic conditions. Because imiquimod-related EM is rare, particularly in children, this article also reviews the potential adverse effects of this drug and the main characteristics of imiquimod-induced EM, especially in similar cases reported in the literature. Clinicians should be aware that topical imiquimod can induce EM, and this medication should be added to the extensive list of drugs that can trigger the condition.

Overexpression of ca1pase Decreases Rubisco Abundance and Grain Yield in Wheat.

Rubisco catalyzes the fixation of CO2 into organic compounds that are used for plant growth and the production of agricultural products, and specific sugar-phosphate derivatives bind tightly to the active sites of Rubisco, locking the enzyme in a catalytically inactive conformation. 2-carboxy-d-arabinitol-1-phosphate phosphatase (CA1Pase) dephosphorylates such tight-binding inhibitors, contributing to the maintenance of Rubisco activity. Here, we investigated the hypothesis that overexpressing ca1pase would decrease the abundance of Rubisco inhibitors, thereby increasing the activity of Rubisco and enhancing photosynthetic performance and productivity in wheat (Triticum aestivum). Plants of four independent wheat transgenic lines overexpressing ca1pase showed up to 30-fold increases in ca1pase expression compared to the wild type. Plants overexpressing ca1pase had lower numbers of Rubisco tight-binding inhibitors and higher Rubisco activation state than the wild type; however, there were 17% to 60% fewer Rubisco active sites in the four transgenic lines than in the wild type. The lower Rubisco content in plants overexpressing ca1pase resulted in lower initial and total carboxylating activities measured in flag leaves at the end of the vegetative stage and lower aboveground biomass and grain yield measured in fully mature plants. Hence, contrary to what would be expected, ca1pase overexpression decreased Rubisco content and compromised wheat grain yields. These results support a possible role for Rubisco inhibitors in protecting the enzyme and maintaining an adequate number of Rubisco active sites to support carboxylation rates in planta.

The Role of Anxiety in Patients With Persistent Atrial Fibrillation Undergoing Elective Cardioversion: An Observational Study.

OBJECTIVE: Anxiety is often present among patients with atrial fibrillation (AF). This condition has been associated with greater symptom severity and worse quality of life in these patients. However, the influence of anxiety on the risk of AF recurrence is not well known. We aimed to define the level of anxiety in patients with persistent AF undergoing elective cardioversion (EC) and determine whether there is an association between anxiety and the risk of early AF recurrence after EC. METHODS: Anxiety was measured before EC using the State-Trait Anxiety Inventory. Early AF recurrence was assessed with a control electrocardiogram at 30-day follow-up. RESULTS: We included 107 patients undergoing effective EC. Early AF recurrence was diagnosed in 40 patients (37.4%). Compared with those who remained in sinus rhythm, individuals with early AF recurrence had significantly higher levels of trait anxiety (23.1 [10.4] versus 17.9 [9.5]; p = .013) and larger left atrial volume index (45.8 [12.3] versus 37.9 [13.3] ml/m; p = .004). Both variables remained independently associated with early AF recurrence after multivariate analysis. A predictive model including trait anxiety score >20 and left atrial volume index >41 ml/m showed acceptable accuracy for the diagnosis of early AF recurrence (area under the curve = 0.733; 95% confidence interval = 0.634-0.832; p < .001). CONCLUSIONS: Our study shows that trait anxiety is an independent risk factor for early AF recurrence after EC. Further studies are warranted to assess the beneficial role of anxiety-reducing strategies on the outcomes of patients with AF.

NavMol 3.0: enabling the representation of metabolic reactions by blind users.

Summary: The representation of metabolic reactions strongly relies on visualization, which is a major barrier for blind users. The NavMol software renders the communication and interpretation of molecular structures and reactions accessible by integrating chemoinformatics and assistive technology. NavMol 3.0 provides a molecular editor for metabolic reactions. The user can start with templates of reactions and build from such cores. Atom-to-atom mapping enables changes in the reactants to be reflected in the products (and vice-versa) and the reaction centres to be automatically identified. Blind users can easily interact with the software using the keyboard and text-to-speech technology. Availability and implementation: NavMol 3.0 is free and open source under the GNU general public license (GPLv3), and can be downloaded at http://sourceforge.net/projects/navmol as a JAR file. Contact: joao@airesdesousa.com.

(R)-Metacycloprodigiosin-HCl: Chiroptical properties and structure.

(R)-Metacycloprodigiosin can exist in three different tautomeric forms, each with hydrogens at C9' and C12 in syn or anti orientation. With the addition of HCl, this structural diversity reduces to syn-(R)-metacycloprodigiosin-HCl (1a) and anti-(R)-metacycloprodigiosin-HCl (1b), each with multiple conformers. Energetics and chiroptical properties, namely, electronic circular dichroism (ECD) and specific optical rotation (SOR), of (R)-metacycloprodigiosin-HCl have been investigated at B3LYP/6-311++G(2d,2p) level. The experimental ECD spectra of (R)-metacycloprodigiosin-HCl have also been measured. Calculations indicated that the lowest energy conformer of 1b is approximately 2.7 kcal/mol lower in energy than that of 1a, and the energy barrier for anti to syn conversion is approximately 13 kcal/mol. The population weighted calculated SORs of 1a and 1b are, respectively, positive and negative. The respective calculated ECD spectra of these pseudoenantiomers show an almost mirror image relationship between them. The experimental SOR and ECD compare well with those predicted for 1b. Thus, 1b is expected to be predominant, a situation confirmed also by nuclear Overhauser effect (NOE) data, with a similar conclusion reached for prodigiosin R1.

Do carcasses of lambs finished on commercial production systems meet market standards?

This study aimed to characterize a commercial lamb finishing system using animals of undefined breed from production to slaughter by analyzing performance, carcass traits, yield of commercial cuts, and the quality and meat acceptance of different slaughter groups, as to evaluate whether this system provides the market with a standardized product. The lots were not homogeneous for yield of commercial cuts and performance and morphometric traits evaluated in vivo. The groups were heterogeneous to 75% of the 13 carcass traits evaluated, among them, hot and cold carcass weights, hot and cold carcass yields, carcass grade finishing and biological yield. There was also no uniformity for the proportion of non-carcass components, morphometry of carcass, visual appraisals, and loin traits. On the other hand, homogeneity was achieved in physico-chemical and sensory traits, except for hardness and proportion of saturated, monounsaturated and polyunsaturated fatty acids. We conclude that the commercial finishing system with the use of undefined crossbred lambs does not produce carcass and cuts standardized to the market.

The experience of male spouses in the context of breast cancer: a systematic review of the literature.

The purpose of this systematic review is to look into how the experience of husbands of women treated for breast cancer is approached in the literature. Between July and August 2015, the databases of PubMed, SciELO and BIREME were searched for papers published in the period January 2005-July 2015; a final sample of 23 papers was defined. The studies listed several negative and positive aspects of the experience, such as financial difficulties, psychological distress, lack of coping skills among family members, social recognition of the role of caregiver, acquisition of new responsibilities and the maturing of family members.

Chiroptical properties of streptorubin B: the synergy between theory and experiment.

Analysis of the calculated and measured optical rotation (OR) together with other calculated chiroptical properties such as electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) of the prodigiosin alkaloid streptorubin B shows that these are dominated by the pseudoenantiomeric atropisomers anti-(S)-streptorubin B (1A) and syn-(S)-streptorubin (1B). Atropisomerism is a dynamic phenomenon with a potentially nonequilibrium population of isomers, and accordingly the measured chiroptical responses may vary with time, concentration, temperature, and the anion of the salts used. Streptorubin also has the potential to form stacked homodimers for which the optical rotations measured at 589 nm can vary greatly due to the presence of ECD-active electronic transitions in this region.

Purification of Rubisco from Leaves.

Rubisco fixes CO2 through the carboxylation of ribulose 1,5-bisphosphate (RuBP) during photosynthesis, enabling the synthesis of organic compounds. The natural diversity of Rubisco properties represents an opportunity to improve its performance and there is considerable research effort focusing on better understanding the properties and regulation of the enzyme. This chapter describes a method for large-scale purification of Rubisco from leaves. After the extraction of Rubisco from plant leaves, the enzyme is separated from other proteins by fractional precipitation with polyethylene glycol followed by ion-exchange chromatography. This method enables the isolation of Rubisco in large quantities for a wide range of biochemical applications.

Envenomation by a common green racer (Chlorosoma viridissimum) in the Brazilian Amazon: A report of three cases.

Envenomations by the common green racer (Chlorosoma viridissimum) are seldom reported in the literature. Herein, we report three cases caused by the same specimen of C. viridissimum in three different victims in the Brazilian Amazon. In all cases, the victims were either a biologist or biology students that were handling the animal and were bitten in their upper limbs. The victims showed only local symptoms, such as edema, tooth marks, pain, erythema, ecchymoses and bleeding. One of the patients presented extensive ecchymosis. Two patients sought medical care, but were only treated for local manifestations and evolved without complications. Chlorosoma viridissimum is capable of provoking mild to moderate signs and symptoms.

Physiological and Molecular Responses of Woody Plants Exposed to Future Atmospheric CO2 Levels under Abiotic Stresses.

Climate change is mainly driven by the accumulation of carbon dioxide (CO2) in the atmosphere in the last century. Plant growth is constantly challenged by environmental fluctuations including heat waves, severe drought and salinity, along with ozone accumulation in the atmosphere. Food security is at risk in an increasing world population, and it is necessary to face the current and the expected effects of global warming. The effects of the predicted environment scenario of elevated CO2 concentration (e[CO2]) and more severe abiotic stresses have been scarcely investigated in woody plants, and an integrated view involving physiological, biochemical and molecular data is missing. This review highlights the effects of elevated CO2 in the metabolism of woody plants and the main findings of its interaction with abiotic stresses, including a molecular point of view, aiming to improve the understanding of how woody plants will face the predicted environmental conditions. Overall, e[CO2] stimulates photosynthesis and growth and attenuates mild to moderate abiotic stress in woody plants if root growth and nutrients are not limited. Moreover, e[CO2] does not induce acclimation in most tree species. Some high-throughput analyses involving omics techniques were conducted to better understand how these processes are regulated. Finally, knowledge gaps in the understanding of how the predicted climate condition will affect woody plant metabolism were identified, with the aim of improving the growth and production of this plant species.

[Usefulness of the administration of intravenous iron sucrose for the correction of preoperative anemia in major surgery patients]. / Utilidad de la administración de hierro sacarosa intravenoso para la corrección de la anemia preoperatoria en pacientes programados para cirugía mayor.

BACKGROUND AND OBJECTIVE: There is a high incidence of perioperative anemia among surgical patients (20%-70%). Preoperative anemia has been linked to an increased postoperative morbidity and mortality, as well as a decreased quality of life of surgical patients. In addition, a low preoperative hemoglobin constitutes an important predictive factor of allogeneic blood transfusion in major surgery. We evaluated the efficacy of intravenous iron sucrose (IVIS) administration for correction of anemia in these patient populations. PATIENTS AND METHOD: Data from 84 patients with anemia who were scheduled for major elective surgery (30 colon cancer resections, 33 abdominal hysterectomies, 21 lower limb arthroplasties) and who received preoperative IVIS during 3-5 weeks were propectively collected. RESULTS: Administration of IVIS -mean dose (standard deviation): 1000 (440)mg- caused a significant increase of hemoglobin levels -2.0 (1.6)g/dl (p<0.001)- and anemia was resolved in 58% of patients. No life-threatening adverse effect was witnessed. CONCLUSIONS: Because of the low incidence of side effects and the rapid increase of hemoglobin levels, IVIS emerges as a safe, effective drug for treating preoperative anemia in these patient populations.

Immune Responses after Vascular Photodynamic Therapy with Redaporfin.

Photodynamic therapy (PDT) relies on the administration of a photosensitizer (PS) that is activated, after a certain drug-to-light interval (DLI), by the irradiation of the target tumour with light of a specific wavelength absorbed by the PS. Typically, low light doses are insufficient to eradicate solid tumours and high fluence rates have been described as poorly immunogenic. However, previous work with mice bearing CT26 tumours demonstrated that vascular PDT with redaporfin, using a low light dose delivered at a high fluence rate, not only destroys the primary tumour but also reduces the formation of metastasis, thus suggesting anti-tumour immunity. This work characterizes immune responses triggered by redaporfin-PDT in mice bearing CT26 tumours. Our results demonstrate that vascular-PDT leads to a strong neutrophilia (2-24 h), systemic increase of IL-6 (24 h), increased percentage of CD4+ and CD8+ T cells producing IFN-γ or CD69+ (2-24 h) and increased CD4+/CD8+ T cell ratio (2-24 h). At the tumour bed, T cell tumour infiltration disappeared after PDT but reappeared with a much higher incidence one day later. In addition, it is shown that the therapeutic effect of redaporfin-PDT is highly dependent on neutrophils and CD8+ T cells but not on CD4+ T cells.

Photoinhibition of Photosystem I Provides Oxidative Protection During Imbalanced Photosynthetic Electron Transport in Arabidopsis thaliana.

Photosynthesis involves the conversion of sunlight energy into stored chemical energy, which is achieved through electron transport along a series of redox reactions. Excess photosynthetic electron transport might be dangerous due to the risk of molecular oxygen reduction, generating reactive oxygen species (ROS) over-accumulation. Avoiding excess ROS production requires the rate of electron transport to be coordinated with the capacity of electron acceptors in the chloroplast stroma. Imbalance between the donor and acceptor sides of photosystem I (PSI) can lead to inactivation, which is called PSI photoinhibition. We used a light-inducible PSI photoinhibition system in Arabidopsis thaliana to resolve the time dynamics of inhibition and to investigate its impact on ROS production and turnover. The oxidation state of the PSI reaction center and rates of CO2 fixation both indicated strong and rapid PSI photoinhibition upon donor side/acceptor side imbalance, while the rate of inhibition eased during prolonged imbalance. PSI photoinhibition was not associated with any major changes in ROS accumulation or antioxidant activity; however, a lower level of lipid oxidation correlated with lower abundance of chloroplast lipoxygenase in PSI-inhibited leaves. The results of this study suggest that rapid activation of PSI photoinhibition under severe photosynthetic imbalance protects the chloroplast from over-reduction and excess ROS formation.

A resistant cowpea (Vigna unguiculata [L.] Walp.) genotype became susceptible to cowpea severe mosaic virus (CPSMV) after exposure to salt stress.

In nature, plants are simultaneously challenged by biotic and abiotic stresses. However, little is known about the effects of these combined stresses for most crops. This work aimed to evaluate the responsed of the virus-resistant cowpea genotype BRS-Marataoã to the exposure of salt stress combined with CPSMV infection. Cowpea plants were exposed to 200 mM NaCl either simultaneously (SV plant group) or 24 h prior to the CPSMV infection [S(24 h)V plant group]. Physiological, biochemical, and proteomic analyses at 2 and 6 days post salt stress (DPS) revealed that cowpea significantly reprogrammed its cellular metabolism. Indeed, plant size, photosynthetic parameters (net photosynthesis, transpiration rate, stomatal conductance, and internal CO2 partial pressure) and chlorophyll and carotenoid contents were reduced in S(24 h)V compared to SV. Moreover, accumulation of viral particles at 6 DPS in S(24 h)V was observed indicating that the salt stress imposed prior to virus infection favors viral particle proliferation. Proteomic analysis showed differential contents of 403 and 330 proteins at 2 DPS and 6 DPS, respectively, out of 733 differentially abundant proteins between the two plant groups. The altered leaf proteins are involved in energy and metabolism, photosynthesis, stress response, and oxidative burst. BIOLOGICAL SIGNIFICANCE: This is an original study in which a virus-resistant cowpea genotype (BRS-Marataoã) was (i) exposed simultaneously to 200 mM NaCl and inoculation with CPSMV (SV plant group) or (ii) exposed to 200 mM NaCl stress 24 h prior to inoculation with CPSMV [S(24 h)V plant group]. The purpose was to shed light on how this CPSMV resistant cowpea responded to the combined stresses. Numerous key proteins and associated pathways were altered in the cowpea plants challenged with both stresses, but unexpectedly, the salt stress imposed 24 h prior to CPSMV inoculation allowed viral proliferation, turning the cowpea genotype from resistant to susceptible.