scholarly journals Triose phosphate utilization and beyond: from photosynthesis to end-product synthesis

2018 ◽  
Author(s):  
Alan M. McClain ◽  
Thomas D. Sharkey

AbstractDuring photosynthesis plants fix CO2 from the atmosphere onto ribulose-bisphosphate producing 3-phosphoglycerate, which is reduced to triose phosphates (TPs). The TPs are then converted into the end products of photosynthesis. When a plant is photosynthesizing very quickly it may not be possible to commit photosynthate to end product as fast as it is produced, causing a decrease in available phosphate and limiting the rate of photosynthesis to the rate of triose phosphate utilization (TPU). The occurrence of an observable TPU limitation is highly variable based on species and especially growth conditions, with TPU capacity seemingly regulated to be in just slight excess of the likely photosynthetic rate. The physiological effects of TPU limitation are discussed with an emphasis on interactions between the Calvin-Benson cycle and the light reactions. Methods for detecting TPU-limited data from gas exchange data are detailed, and the impact on modeling of some physiological effects are shown. Special consideration is given to common misconceptions about TPU.HighlightPhotosynthetic triose phosphate utilization limitation is discussed, highlighting misleading points in physiology and focusing on regulation.

2019 ◽  
Vol 70 (6) ◽  
pp. 1755-1766 ◽  
Author(s):  
Alan M McClain ◽  
Thomas D Sharkey

Abstract During photosynthesis, plants fix CO2 from the atmosphere onto ribulose-bisphosphate, producing 3-phosphoglycerate, which is reduced to triose phosphates (TPs). The TPs are then converted into the end products of photosynthesis. When a plant is photosynthesizing very quickly, it may not be possible to commit photosynthate to end products as fast as it is produced, causing a decrease in available phosphate and limiting the rate of photosynthesis to the rate of triose phosphate utilization (TPU). The occurrence of an observable TPU limitation is highly variable based on species and especially growth conditions, with TPU capacity seemingly regulated to be in slight excess of typical photosynthetic rates the plant might experience. The physiological effects of TPU limitation are discussed with an emphasis on interactions between the Calvin–Benson cycle and the light reactions. Methods for detecting TPU-limited data from gas exchange data are detailed and the impact on modeling of some physiological effects are shown. Special consideration is given to common misconceptions about TPU.


2011 ◽  
Vol 10 (2) ◽  
pp. 1
Author(s):  
Y. ARBI ◽  
R. BUDIARTI ◽  
I G. P. PURNABA

Operational risk is defined as the risk of loss resulting from inadequate or failed internal processes or external problems. Insurance companies as financial institution that also faced at risk. Recording of operating losses in insurance companies, were not properly conducted so that the impact on the limited data for operational losses. In this work, the data of operational loss observed from the payment of the claim. In general, the number of insurance claims can be modelled using the Poisson distribution, where the expected value of the claims is similar with variance, while the negative binomial distribution, the expected value was bound to be less than the variance.Analysis tools are used in the measurement of the potential loss is the loss distribution approach with the aggregate method. In the aggregate method, loss data grouped in a frequency distribution and severity distribution. After doing 10.000 times simulation are resulted total loss of claim value, which is total from individual claim every simulation. Then from the result was set the value of potential loss (OpVar) at a certain level confidence.


2021 ◽  
Vol 11 (6) ◽  
pp. 483
Author(s):  
Marwa Saadaoui ◽  
Manoj Kumar ◽  
Souhaila Al Khodor

The COVID-19 pandemic is a worldwide, critical public health challenge and is considered one of the most communicable diseases that the world had faced so far. Response and symptoms associated with COVID-19 vary between the different cases recorded, but it is amply described that symptoms become more aggressive in subjects with a weaker immune system. This includes older subjects, patients with chronic diseases, patients with immunosuppression treatment, and pregnant women. Pregnant women are receiving more attention not only because of their altered physiological and immunological function but also for the potential risk of viral vertical transmission to the fetus or infant. However, very limited data about the impact of maternal infection during pregnancy, such as the possibility of vertical transmission in utero, during birth, or via breastfeeding, is available. Moreover, the impact of infection on the newborn in the short and long term remains poorly understood. Therefore, it is vital to collect and analyze data from pregnant women infected with COVID-19 to understand the viral pathophysiology during pregnancy and its effects on the offspring. In this article, we review the current knowledge about pre-and post-natal COVID-19 infection, and we discuss whether vertical transmission takes place in pregnant women infected with the virus and what are the current recommendations that pregnant women should follow in order to be protected from the virus.


Ecotoxicology ◽  
2021 ◽  
Author(s):  
Sabaridasan Arumugam ◽  
Mohamed Shahila Abul Asan Sathali ◽  
Soranam Ramaiah ◽  
Gandhimaniyan Krishnan

Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 933
Author(s):  
Andrea Gila-Diaz ◽  
Gloria Herranz Carrillo ◽  
Pratibha Singh ◽  
David Ramiro-Cortijo

Cardiovascular disease remains a leading cause of mortality worldwide. Unresolved inflammation plays a critical role in cardiovascular diseases development. Specialized Pro-Resolving Mediators (SPMs), derived from long chain polyunsaturated fatty acids (LCPUFAs), enhances the host defense, by resolving the inflammation and tissue repair. In addition, SPMs also have anti-inflammatory properties. These physiological effects depend on the availability of LCPUFAs precursors and cellular metabolic balance. Most of the studies have focused on the impact of SPMs in adult cardiovascular health and diseases. In this review, we discuss LCPUFAs metabolism, SPMs, and their potential effect on cardiovascular health and diseases primarily focusing in neonates. A better understanding of the role of these SPMs in cardiovascular health and diseases in neonates could lead to the development of novel therapeutic approaches in cardiovascular dysfunction.


Sexual Health ◽  
2016 ◽  
Vol 13 (5) ◽  
pp. 428 ◽  
Author(s):  
Justin R. Garcia ◽  
Amanda N. Gesselman ◽  
Shadia A. Siliman ◽  
Brea L. Perry ◽  
Kathryn Coe ◽  
...  

Background: The transmission of sexual images and messages via mobile phone or other electronic media (sexting) has been associated with a variety of mostly negative social and behavioural consequences. Research on sexting has focussed on youth, with limited data across demographics and with little known about the sharing of private sexual images and messages with third parties. Methods: The present study examines sexting attitudes and behaviours, including sending, receiving, and sharing of sexual messages and images, across gender, age, and sexual orientation. A total of 5805 single adults were included in the study (2830 women; 2975 men), ranging in age from 21 to 75+ years. Results: Overall, 21% of participants reported sending and 28% reported receiving sexually explicit text messages; both sending and receiving ‘sexts’ was most common among younger respondents. Although 73.2% of participants reported discomfort with unauthorised sharing of sexts beyond the intended recipient, of those who had received sext images, 22.9% reported sharing them with others (on average with 3.17 friends). Participants also reported concern about the potential consequences of sexting on their social lives, careers, and psychosocial wellbeing. Conclusion: Views on the impact of sexting on reputation suggest a contemporary struggle to reconcile digital eroticism with real-world consequences. These findings suggest a need for future research into negotiations of sexting motivations, risks, and rewards.


2016 ◽  
Vol 101 (9) ◽  
pp. e2.12-e2 ◽  
Author(s):  
Noor Al-Adhami ◽  
Karen Whitfield ◽  
Angela North

AimTo eliminate the prescribing of codeine and codeine combination products postpartum to improve safety in breast fed infants.Concerns have been raised over the use of codeine and codeine combination products during breast feeding after the death of a neonate whose mother had been prescribed codeine postpartum. High concentrations of morphine were found in the infant's blood and this was attributed to the mother being a CYP2D6 ultrafast metaboliser.1 MethodsThe evidence surrounding the safety of codeine and codeine combination products in children, during the postpartum period and specifically for breast fed infants was collated. The evidence was presented to key stakeholders including obstetricians, midwives, safety and quality representatives, nurse unit managers and acute pain team representatives. Postpartum analgesia was discussed and an agreed protocol developed. Training and education sessions were undertaken to obstetric medical and nursing staff.ResultsThe evidence that was presented to key stakeholders included:▸ Reports over the safety concerns surrounding the use of codeine and codeine combination products during breast feeding▸ Guidelines and contraindications about the use of codeine in children that had been issued by international regulatory bodies (US Food and Drug Administration and European Medicines Agency).▸ Recommendations from the Australian Medicines Handbook to avoid in breast feeding2 ▸ Recommendations from Hale's Medications and Mothers Milk that reported limited data and had made a recent re-classification from L3 (limited data–probably compatible) to L4 (limited data–possibly hazardous).3 Before presenting the evidence to key stakeholders and undertaking training to nursing and medical staff, more than 90% of postpartum women were prescribed a codeine containing product as part of their ‘as required’ analgesic regimen.Since the intervention, codeine combination products have now been almost completely eliminated on medication charts for postpartum women (less than 5%). Those that are prescribed are ceased once highlighted to medical staff. The obstetric pharmacist now presents a session on postpartum analgesia at every new resident medical officer orientation outlining suitable medications to prescribe. In addition all new pharmacists to the women's and new born's team receive training about postpartum analgesia.ConclusionThis study highlights the impact that can be achieved when health care professionals work together to change the culture and prescribing habits in a hospital setting, to enhance patient safety. Evaluating the evidence and presenting to stakeholders as well as providing ongoing training and education to medical, nursing and pharmacy staff are all essential to a successful outcome.


2018 ◽  
Vol 56 (12) ◽  
Author(s):  
Twisha S. Patel ◽  
Peggy L. Carver ◽  
Gregory A. Eschenauer

ABSTRACT The purpose of this review is to critically analyze published data evaluating the impact of azole pharmacokinetic and pharmacodynamic parameters, MICs, and Candida species on clinical outcomes in patients with candidemia. Clinical breakpoints (CBPs) for fluconazole and voriconazole, which are used to determine susceptibility, have been defined by the Clinical and Laboratory Standards Institute (CLSI) for Candida species. Studies evaluating the relationship between treatment efficacy and in vitro susceptibility, as well as the pharmacodynamic targets, have been conducted in patients treated with fluconazole for candidemia; however, for species other than Candida albicans and Candida glabrata, and for other forms of invasive candidiasis, data remain limited and randomized trials are not available. Limited data evaluating these relationships with voriconazole are available. While pharmacodynamic targets for posaconazole and isavuconazole have been proposed based upon studies conducted in murine models, CBPs have not been established by CLSI. Fluconazole remains an important antifungal agent for the treatment of candidemia, and data supporting its use based on in vitro susceptibility are growing, particularly for C. albicans and C. glabrata. Further investigation is needed to establish the roles of voriconazole, posaconazole, and isavuconazole in the treatment of candidemia and for all agents in the treatment of other forms of invasive candidiasis.


2020 ◽  
Vol 47 (3) ◽  
pp. 298-308
Author(s):  
K. R. Idowu ◽  
A. S. Chaudhry ◽  
J. Dolfing ◽  
V. O. A. Ojo

Fungal improvement of the nutritive content of low-quality forages can be affected by several factors among which loss of water-soluble content (WSC) plays a major role. To achieve this aim, two growth conditions i.e. forage-liquid ratios (1:3 and 1:5) and two inoculation times (14 and 28 days) were used to cultivate the selected fungi i.e. Pleurotus ostreatus (PO) at 30°C and Ceriporiopsis rivulosus (CR) at 20°C on Brachiaria decumbens (BD), Andropogon gayanus (AG), Triticum aestivum (TA) straw, Lolium perenne (LP), respectively with the view of selecting the optimal conditions that facilitate the release of WSC. The impact that losses of WSC have on the ability of fungi to improve the nutritive content (i.e. proximate, fibre, secondary metabolites and total antioxidant content) of the forages were then measured using 2 filtering methods i.e. light pump filtering method (LFM) and free flow filtering method (FFM). The optimal conditions that supported increased th soluble was identified as 28th day for both fungi; forage-liquid ratio of 1:5 for both fungi in most of the forages except BD (CR) and BD & AG (PO). The LFM led to lesser or no improvement in the nutritive quality of the upgraded forages while the opposite was recorded with the LFM. The LFM as against the FFM produced upgraded forages with lesser reduction in NDF; similar or higher ADF and lignin contents; and similar reduction in secondary metabolites and TAC when compared with un-improved forages. It can be concluded that the fungal improvement of the nutritive content of low-quality forages was negatively affected by the loss of WSC. It is therefore recommended that fungal improvement of the nutritive quality of low quality forages should be carried out with methods or techniques that facilitates little or no WSC loss in the upgraded forages.


2021 ◽  
Vol 7 (1) ◽  
pp. 6-13
Author(s):  
Kiran Batra ◽  
Manish Mohanka ◽  
Srinivas Bollineni ◽  
Vaidehi Kaza ◽  
Prabhakar Rajiah ◽  
...  

Abstract Introduction There is limited data on the impact of extracorporeal membrane oxygenation (ECMO) on pulmonary physiology and imaging in adult patients. The current study sought to evaluate the serial changes in oxygenation and pulmonary opacities after ECMO initiation. Methods Records of patients started on veno-venous, or veno-arterial ECMO were reviewed (n=33; mean (SD): age 50(16) years; Male: Female 20:13). Clinical and laboratory variables before and after ECMO, including daily PaO2 to FiO2 ratio (PFR), were recorded. Daily chest radiographs (CXR) were prospectively appraised in a blinded fashion and scored for the extent and severity of opacities using an objective scoring system. Results ECMO was associated with impaired oxygenation as reflected by the drop in median PFR from 101 (interquartile range, IQR: 63-151) at the initiation of ECMO to a post-ECMO trough of 74 (IQR: 56-98) on post-ECMO day 5. However, the difference was not statistically significant. The appraisal of daily CXR revealed progressively worsening opacities, as reflected by a significant increase in the opacity score (Wilk’s Lambda statistic 7.59, p=0.001). During the post-ECMO period, a >10% increase in the opacity score was recorded in 93.9% of patients. There was a negative association between PFR and opacity scores, with an average one-unit decrease in the PFR corresponding to a +0.010 increase in the opacity score (95% confidence interval: 0.002 to 0.019, p-value=0.0162). The median opacity score on each day after ECMO initiation remained significantly higher than the pre-ECMO score. The most significant increase in the opacity score (9, IQR: -8 to 16) was noted on radiographs between pre-ECMO and forty-eight hours post-ECMO. The severity of deteriorating oxygenation or pulmonary opacities was not associated with hospital survival. Conclusions The use of ECMO is associated with an increase in bilateral opacities and a deterioration in oxygenation that starts early and peaks around 48 hours after ECMO initiation.


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