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Physiological adaptations during pregnancy alter nutrient and energy metabolism. Creatine may be important for maintaining cellular energy homeostasis throughout pregnancy. However, the impact of pregnancy on endogenous and exogenous creatine availability has never been comprehensively explored.

Creatine metabolism likely contributes to energy homeostasis in the human uterus, but whether this organ synthesizes creatine and whether creatine metabolism is adjusted throughout the menstrual cycle and with pregnancy are largely unknown. This study determined endometrial protein expression of creatine-synthesizing enzymes arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT), creatine kinase (CKBB), and the creatine transporter (SLC6A8) throughout the menstrual cycle in fertile and primary infertile women. It also characterized creatine metabolism at term pregnancy, measuring aspects of creatine metabolism in myometrial and decidual tissue. In endometrial samples, AGAT, GAMT, SLC6A8, and CKBB were expressed in glandular and luminal epithelial cells. Except for SLC6A8, the other proteins were also located in stromal cells. Irrespective of fertility, AGAT, GAMT, and SLC6A8 high-intensity immunohistochemical staining was greatest in the early secretory phase of the menstrual cycle. During the proliferative phase, staining for SLC6A8 protein was greater (P= 0.01) in the primary infertile compared with the fertile group. Both layers of the term pregnant uterus contained creatine, phosphocreatine, guanidinoacetic acid, arginine, glycine, and methionine; detectable gene and protein expression of AGAT, GAMT, CKBB, and ubiquitous mitochondrial CK (uMt-CK); and gene expression of SLC6A8. The proteins AGAT, GAMT, CKBB, and SLC6A8 were uniformly distributed in the myometrium and localized to the decidual glands. In conclusion, endometrial tissue has the capacity to produce creatine and its capacity is highest around the time of fertilization and implantation. Both layers of the term pregnant uterus also contained all the enzymatic machinery and substrates of creatine metabolism.The human uterus has the capacity to produce, transport and metabolise creatine during the menstrual cycle and at term pregnancy, with this capacity is up-regulated during the early secretory phase of the menstrual cycle.Graphical Abstract

The complex process of photosynthesis requires precise arrangements of light harvesting molecules in the photosynthetic system. Artificial imitation of such reaction systems is difficult as they involve complex protein structures. Global population increase and the associated rise in demand for food have become a vital concern in the present and therefore it is essential to develop methods to improve agricultural yields, enhancing photosynthesis could be key to this. An approach is the use of self-assembling systems which are embedded into plants to enhance the activity of photo-functional pigments. This review discusses various nanoparticle mediated artificially embedded photosystems used to enhance photosynthesis. It also includes the mechanisms of interaction between nanoparticles and photosystem for enhancing photosynthesis due to the involvement of a light-harvesting function. The use of self-assembling systems to improve photosynthesis could increase productivity of plants, particularly in regions or seasons with low duration of sunlight. Plant nanobionics offers scope towards embedding nanostructures into plant systems and supplementing them with additional properties to enhance the efficiency of plants in terms of resistance to pathogens, adaptability to abiotic and biotic stresses, in addition to improving sunlight harnessing ability and energy conversion. This review also highlights the importance of functionalised nanoparticles with tunable structures to produce desirable properties. A mechanistic view of the nanoparticle interaction with plants will help us realise the potential and facilitate appropriate application of nanoparticles in plants for photosynthesis enhancement.

ABSTRACTAgaricus xanthodermusand other species of the yellow-staining section Xanthodermateiare responsible for mushroom-related poisoning cases that require treatment. However, longstanding anecdotal evidence indicates that this species appears to exhibit considerable variation in toxicity, resulting in gastrointestinal irritation of varying severity in most cases. We quantified the amount of phenol, hydroquinone, and catechol in mushrooms using a novel protocol for gas chromatography–mass spectrometry (GC-MS) and investigated their levels in different basidiomatal structures, different developmental stages, and on different nutritional substrates. Phenol concentration was greater in the pileus than the stipe, in mature compared with immature basidiomata, and in basidiomata occurring in woody mulch versus lawns. Variation in toxicity is suggested to be due in part to variation in phenol concentration, developmental stage and tissue type consumed, and substrate. Variation in human sensitivity to simple phenols may also play a role but was not formally investigated in this study.

Rapid campus closure and unexpected transition to emergency online teaching of a large first year chemistry unit provided an opportunity to explore the level of student engagement and factors associated with success in this online transition. Here, we compared the standard offering in 2019 to the online version in 2020 by examining the completion of weekly assessment tasks and the uptake of learning activities. In spite of a preference for face-to-face learning, we found that students were able to quickly adapt to using the technology, with high levels of access to live streamed and recorded lectures, in-class polling, and online tutorials, together with large increases in discussion forum use. The change in level of engagement in low stakes assessment tasks over the course of the semester was similar for both years. Each form of engagement was associated with increased likelihood of success in the unit, whether this was being taught face-to-face or online. Of the multiple forms of engagement measured, only tutorial participation had a significantly lower impact on student success in the online compared to the face-to-face environment.

The closure of campuses in early 2020 due to the COVID-19 pandemic meant that scheduled practical activities for introductory chemistry students could not take place. The first practical class started prior to shutdown, and 21.5% of the students undertook the face-to-face offering. The remainder completed an online offering consisting of the same worksheet with videos of each of the tasks, which relate to ions in solution: conductivity and precipitation. A Kruskal–Wallis rank sum test comparison of the marks for the first practical showed that online students had, on average, a 0.9/10 drop in their mark compared to the face-to-face cohort. We concluded that a significant proportion of students found the transition to online learning difficult with the technology we provided. Rather than add another online learning activity, we chose to develop simple activities that students could complete at home, along with worksheets linking their observations to the theory taught in class. The first kitchen chemistry activity included experimental measurement (timing water boiling), solubility (mixing water with salt, sugar or oil), heat capacity (heating salt, sugar, butter and water), combustion calculations for gas heating, and colligative properties (timing ice melting with and without added salt). The second kitchen chemistry activity involved adding a constant amount of sodium bicarbonate to differing amounts of vinegar to explore stoichiometry; relating this to gas law calculations, and an extraction of red cabbage or other colored food to investigate the pH of household items. The aims of the kitchen chemistry experiments were to develop student observation skills, emphasize the importance of measurement and significant figures and provide some simple hands-on and relevant activities that could be done safely at home. The proportion of students who submitted online chemistry practicals was the same as typically attends face-to-face practicals (90%). Preliminary evaluation through anonymous student comments and staff reflections suggests that this was a valuable exercise: most students were able to learn in this replacement hands-on environment, receiving mean scores of 7.5/10 or higher. We conclude that relevant, engaging kitchen chemistry activities are useful for foundation level chemistry students.

Advances in high-throughput, comprehensive small molecule analytical techniques have seen the development of the field of metabolomics. The coupling of mass spectrometry with high-resolution chromatography provides extensive chemical profiles from complex biological extracts. These profiles include thousands of compounds linked to gene expression, and can be used as taxonomic characters. Studies have shown metabolite profiles to be taxon specific in a range of organisms, but few have investigated taxonomically problematic plant taxa. This study used a phenetic analysis of metabolite profiles to test taxonomic boundaries in the Olearia phlogopappa(Asteraceae) complex as delimited by morphological data. Metabolite profiles were generated from both field- and shade hous-egrown material, using liquid chromatography-mass spectrometry (LC-MS). Aligned profiles of 51 samples from 12 taxa gave a final dataset of over 10,000 features. Multivariate analyses of field and shade house material gave congruent results, both confirming the distinctiveness of the morphologically defined species and subspecies in this complex. Metabolomics has great potential in alpha taxonomy, especially for testing the boundaries of closely related taxa where DNA sequence data has been uninformative.

Highly polar metabolites, such as sugars and most amino acids are not retained by conventional RP LC columns. Without sufficient retention low concentration compounds are not detected due ion suppression and structural isomers are not resolved. In contrast, hydrophilic interaction chromatography (HILIC) and aqueous normal phase chromatography (ANP) retain compounds based on their hydrophilicity and therefore provides a means of separating highly polar compounds. Here, an ANP method based on the diamond hydride stationary phase is presented for profiling biological small molecules by LC. A rapid separation system based upon a fast gradient that delivers reproducible chromatography is presented. Approximately 1000 compounds were reproducibly detected in human urine samples and clear differences between these samples were identified. This chromatography was also applied to xylem fluid from soyabean (Glycine max) plants to which 400 compounds were detected. This method greatly increases the metabolite coverage over RP‐only metabolite profiling in biological samples. We show that both forms of chromatography are necessary for untargeted comprehensive metabolite profiling and that the diamond hydride stationary phase provides a good option for polar metabolite analysis.