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Radon, a naturally occurring radioactive gas that can accumulate inside dwellings, represents the second biggest cause of lung cancer globally. In Ireland, radon is linked to approximately 300 lung cancer cases every year, equating to 12% of all lung cancer deaths. Despite the health risks posed by radon air pollution, Ireland lacks well-defined and universally applicable air pollution-related public health policies. Through purposive literature sampling, we critically examine the case of indoor radon policy development in Ireland. Specifically, we analyse the evidence-based policymaking process relating to indoor radon pollution from three different knowledge dimensions, namely political, scientific, and practical knowledge. In doing so, we identify various challenges inherent to pollution-related public policymaking. We highlight the difficulties of balancing and integrating information from multiple disciplines and perspectives and argue that input from multiple scientific areas is crucial, but can only be achieved through continued, dialogic communication between stakeholders. On the basis of our analysis, we suggest that a transdisciplinary perspective, defined as a holistic approach which subordinates disciplines and looks at the dynamics of whole systems, will allow evidence-based policymaking to be effective. We end with recommendations for evidence-based policymaking when it comes to public health hazards such as radon, which are applicable to sustainable air pollution management beyond Ireland.

Modular assembly and heterologous expression in the moss Physcomitrella patens of pairs of diterpene synthases results in accumulation of modern land plant diterpenoids. Physcomitrella patens is a representative of the ancient bryophyte plant lineage with a genome size of 511 Mb, dominant haploid life cycle and limited chemical and metabolic complexity. For these plants, exceptional capacity for genome editing through homologous recombination is met with recently demonstrated in vivo assembly of multiple heterologous DNA fragments. These traits earlier made P. patens an attractive choice as a biotechnological chassis for photosynthesis-driven production of recombinant peptides. The lack of diterpene gibberellic acid phytohormones in P. patens combined with the recent targeted disruption of the single bifunctional diterpene synthase yielded lines devoid of endogenous diterpenoid metabolites and well-suited for engineering of terpenoid production. Here, we mimicked the modular nature of diterpene biosynthetic pathways found in modern land plants by developing a flexible pipeline to install three combinations of class II and class I diterpene synthases in P. patens to access industrially relevant diterpene biomaterials. In addition to a well-established neutral locus for targeted integration, we also explored loci created by a class of Long Terminal Repeat Retrotransposon present at moderate number in the genome of P. patens. Assembly of the pathways and production of the enzymes from the neutral locus led to accumulation of diterpenes matching the reported activities in the angiosperm sources. In contrast, insights gained with the retrotransposon loci indicate their suitability for targeting, but reveal potentially inherent complications which may require adaptation of the experimental design.

Catalyzing stereo- and regio-specific oxidation of inert hydrocarbon backbones, and a range of more exotic reactions inherently difficult in formal chemical synthesis, cytochromes P450 (P450s) offer outstanding potential for biotechnological engineering. Plants and their dazzling diversity of specialized metabolites have emerged as rich repository for functional P450s with the advances of deep transcriptomics and genome wide discovery. P450s are of outstanding interest for understanding chemical diversification throughout evolution, for gaining mechanistic insights through the study of their structure–function relationship, and for exploitation in Synthetic Biology. In this review, we highlight recent developments and examples in the discovery of plant P450s involved in the biosynthesis of industrially relevant monoterpenoids, sesquiterpenoids, diterpenoids and triterpenoids, throughout 2016 and early 2017. Examples were selected to illustrate the spectrum of value from commodity chemicals, flavor and fragrance compounds to pharmacologically active terpenoids. We focus on a recently emerging theme, where P450s control metabolic bifurcations and chemical diversity of the final product profile, either within a pathway, or through neo-functionalization in related species. The implications may inform approaches for rational assembly of recombinant pathways, biotechnological production of high value terpenoids and generation of novel chemical entities. Graphical Abstract

BACKGROUND Ultrasound biomicroscopy (UBM) is a non-invasive procedure to visualise the structures of the anterior segment using high frequency ultrasound. Any abnormalities in the structures like the iris, ciliary body and zonules can be easily detected. In case of corneal oedema, the Descemet’s membrane can be detected with UBM than the slit-lamp biomicroscopy. It plays a useful diagnostic tool in glaucoma. It differentiates between open and closed angle closure. It also helps in the diagnosis of plateau iris configuration and malignant glaucoma. Bleb status and tenon’s cyst can be visualized by the UBM. It plays a major role to rule out angle recession or cyclodialysis cleft in cases of trauma. Zonular dialysis and iridodialysis as well as the integrity of the posterior capsule can be assessed with UBM. It is the only modality which can easily diagnose pars plannits or cyclitic membranes noninvasively. In cases of unexplained hypotony, it helps to diagnose ciliary body atrophy or traction on the ciliary body. This article is a short overview describing the indications and uses of anterior segment pathologies.

Glucose-6-phosphate dehydrogenase (G6PDH) can initiate the glucose-6-phosphate (G6P) shunt around the Calvin–Benson cycle. To understand the regulation of flux through this pathway, we have characterized the biochemical parameters and redox regulation of the three functional plastidic isoforms of Arabidopsis G6PDH. When purified, recombinant proteins were measured, all three exhibited significant substrate inhibition by G6P but not NADP+, making the determination of enzyme kinetic parameters complex. We found that the half-saturation concentration of G6PDH isoform 1 is increased under reducing conditions. The other two isoforms exhibit less redox regulation, however, isoform 2 is strongly inhibited by NADPH. Redox regulation of G6PDH1 can be partially reversed by hydrogen peroxide or protected against by the presence of its substrate, G6P. Overall, our results support the conclusion that G6PDH can have significant activity throughout the day and can be dynamically regulated to allow or prevent flux through the glucose-6-phosphate shunt.

A 5-year-old boy presented with sudden onset diminution of vision in his left eye for 5 days. Patient also had history of intermittent bleeding from gums since 7 days. There was history of fever 25 days back for which he was treated with intravenous antibiotics at local hospital and fever

Cytosolic lipid droplets are endoplasmic reticulum-derived organelles typically found in seeds as reservoirs for physiological energy and carbon to fuel germination. Here, we report synthetic biology approaches to co-produce high-value sesqui- or diterpenoids together with lipid droplets in plant leaves. The formation of cytosolic lipid droplets is enhanced in the transient Nicotiana benthamiana system through ectopic production of WRINKLED1, a key regulator of plastid fatty acid biosynthesis, and a microalgal lipid droplet surface protein. Engineering of the pathways providing the universal C5-building blocks for terpenoids and installation of terpenoid biosynthetic pathways through direction of the enzymes to native and non-native compartments boost the production of target terpenoids. We show that anchoring of distinct biosynthetic steps onto the surface of lipid droplets leads to efficient production of terpenoid scaffolds and functionalized terpenoids. The co-produced lipid droplets “trap” the terpenoids in the cells., Cytosolic lipid droplets are ER-derived organelles that accumulate in seeds to fuel germination. Here, Sadre et al. show that by boosting lipid production and anchoring key terpenoid biosynthetic enzymes to the droplet surface, an efficient terpenoid production platform can be established in leaves.

Invasive sino-orbital aspergillosis is a rare cause of orbital apex syndrome (OAS) in immunocompetent patients and often misdiagnosed as tumour because of its aggressive nature and invasive patterns. We report a 23-year-old immunocompetent man presenting with painful progressive loss of vision, ophthalmoplegia and proptosis of the right eye suggestive of OAS. MRI with gadolinium contrast showed an enhancing heterogeneous mass filling the paranasal sinuses, extraconal space and extending up to the right orbital apex. A functional endoscopic biopsy reported as invasive sino-orbital aspergillosis. He was started on intravenous voriconazole and maximal surgical debridement was done. He gradually regained his vision to 20/30 in the right eye. A review of literature reported several such cases which were managed medically or surgically but with poor visual recovery. This case highlights the need for awareness among clinicians for early diagnosis and treatment to prevent vision loss and better survival.

A 64-year-old hypertensive woman presented with complaints of a painless, progressive decrease in vision, headache, dizziness for the last month. She was a known case of diabetes mellitus on insulin therapy. On examination, best-corrected visual acuity was 6/12 in the right eye and 6/18 in the left eye. The fundus examination in both eyes revealed features of grade IV hypertensive retinopathy. Systemic examination revealed the raised blood pressure of 200/110 mm Hg. Diagnosis of pheochromocytoma was made on the basis of increased urinary norepinephrine (892.8 mg/dL) and mass in the left adrenal gland (measuring 31×28 mm) at contrast-enhanced CT. Medical management to control hypertension was done and ultimately, she underwent left laparoscopic adrenalectomy. After 10 months of surgery, the patient was asymptomatic, blood pressure was within normal limit and her vision improved to 6/6 in both the eyes. The retinal features of hypertensive retinopathy had completely disappeared.

Fructose 6-phosphate is an intermediate in the Calvin-Benson cycle and can be acted on by phosphoglucoisomerase to make glucose 6-phosphate (G6P) for starch synthesis. A high concentration of G6P is favorable for starch synthesis but can also stimulate G6P dehydrogenase initiating the glucose-6-phosphate shunt an alternative pathway around the Calvin-Benson cycle. A low concentration of glucose 6-phosphate will limit this futile cycle. In order to understand the biochemical regulation of plastidic glucose 6-phosphate supply and consumption, we characterized biochemical parameters of two key enzymes, phosphoglucoisomerase (PGI) and G6P dehydrogenase (G6PDH). We have found that the plastidic PGI in has a higherKmfor G6P compared to that for fructose 6-phosphate. TheKmof G6PDH isoform 1 is increased under reducing conditions. The other two isoforms exhibit less redox regulation; isoform 2 is the most inhibited by NADPH. Our results support the conclusion that PGI restricts stromal G6P synthesis limiting futile cycling via G6PDH. It also acts like a one-way valve, allowing carbon to leave the Calvin-Benson cycle but not reenter. We found flexible redox regulation of G6PDH that could regulate the glucose-6-phosphate shunt.HighlightGlucose 6-phosphate stimulates glucose-6-phosphate dehydrogenase. This enzyme is less active during the day but retains significant activity that is very sensitive to the concentration of glucose 6-phopshate.

Deoxyxylulose 5-phosphate synthase (DXS), a thiamine diphosphate (ThDP) dependent enzyme, plays a regulatory role in the methylerythritol 4-phosphate (MEP) pathway. Isopentenyl diphosphate (IDP) and dimethylallyl diphosphate (DMADP), the end products of this pathway, inhibit DXS by competing with ThDP. Feedback inhibition of DXS by IDP and DMADP constitutes a significant metabolic regulation of this pathway. The aim of this work was to experimentally test the effect of key residues of recombinant poplar DXS (PtDXS) in binding both ThDP and IDP. This work also described the engineering of PtDXS to improve the enzymatic activity by reducing its inhibition by IDP and DMADP. We have designed and tested modifications of PtDXS in an attempt to reduce inhibition by IDP. This could possibly be valuable by removing a feedback that limits the usefulness of the MEP pathway in biotechnological applications. Both ThDP and IDP use similar interactions for binding at the active site of the enzyme, however, ThDP being a larger molecule has more anchoring sites at the active site of the enzyme as compared to the inhibitors. A predicted enzyme structure was examined to find ligand-enzyme interactions, which are relatively more important for inhibitor-enzyme binding than ThDP-enzyme binding, followed by their modifications so that the binding of the inhibitors can be selectively affected compared to ThDP. Two alanine residues important for binding ThDP and the inhibitors were mutated to glycine. In two of the cases, both the IDP inhibition and the overall activity were increased. In another case, both the IDP inhibition and the overall activity were reduced. This provides proof of concept that it is possible to reduce the feedback from IDP on DXS activity.

Deoxyxylulose 5-phosphate synthase (DXS), a thiamine diphosphate (ThDP) dependent enzyme, plays a regulatory role in the methylerythritol 4-phosphate (MEP) pathway. Isopentenyl diphosphate (IDP) and dimethylallyl diphosphate (DMADP), the end products of this pathway, inhibit DXS by competing with ThDP. Feedback inhibition of DXS by IDP and DMADP constitutes a significant metabolic regulation of this pathway. The aim of this work was to experimentally test the effect of key residues of recombinant poplar DXS (PtDXS) in binding both ThDP and IDP. This work also described the engineering of PtDXS to improve the enzymatic activity by reducing its inhibition by IDP and DMADP. We have designed and tested modifications of PtDXS in an attempt to reduce inhibition by IDP. This could possibly be valuable by removing a feedback that limits the usefulness of the MEP pathway in biotechnological applications. Both ThDP and IDP use similar interactions for binding at the active site of the enzyme, however, ThDP being a larger molecule has more anchoring sites at the active site of the enzyme as compared to the inhibitors. A predicted enzyme structure was examined to find ligand-enzyme interactions, which are relatively more important for inhibitor-enzyme binding than ThDP-enzyme binding, followed by their modifications so that the binding of the inhibitors can be selectively affected compared to ThDP. Two alanine residues important for binding ThDP and the inhibitors were mutated to glycine. In two of the cases, both the IDP inhibition and the overall activity were increased. In another case, both the IDP inhibition and the overall activity were reduced. This provides proof of concept that it is possible to reduce the feedback from IDP on DXS activity.