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Biocatalytic oxidations are an emerging technology for selective C-H bond activation. While promising for a range of selective oxidations, practical use of enzymes catalyzing aerobic hydroxylation is presently limited by their substrate scope and stability under industrially relevant conditions. Here, we report the engineering and practical application of a non-heme iron and α-ketoglutarate-dependent dioxygenase for the direct stereo- and regio-selective hydroxylation of a non-native fluoroindanone en route to the oncology treatment belzutifan, replacing a five-step chemical synthesis with a direct enantioselective hydroxylation. Mechanistic studies indicated that formation of the desired product was limited by enzyme stability and product overoxidation, with these properties subsequently improved by directed evolution, yielding a biocatalyst capable of >15,000 total turnovers. Highlighting the industrial utility of this biocatalyst, the high-yielding, green, and efficient oxidation was demonstrated at kilogram scale for the synthesis of belzutifan., (© 2024 Wiley-VCH GmbH.)

The introduction of molecular complexity in an atom- and step-efficient manner remains an outstanding goal in modern synthetic chemistry. Artificial biosynthetic pathways are uniquely able to address this challenge by using enzymes to carry out multiple synthetic steps simultaneously or in a one-pot sequence 1-3 . Conducting biosynthesis ex vivo further broadens its applicability by avoiding cross-talk with cellular metabolism and enabling the redesign of key biosynthetic pathways through the use of non-natural cofactors and synthetic reagents 4,5 . Here we describe the discovery and construction of an enzymatic cascade to MK-1454, a highly potent stimulator of interferon genes (STING) activator under study as an immuno-oncology therapeutic 6,7 (ClinicalTrials.gov study NCT04220866 ). From two non-natural nucleotide monothiophosphates, MK-1454 is assembled diastereoselectively in a one-pot cascade, in which two thiotriphosphate nucleotides are simultaneously generated biocatalytically, followed by coupling and cyclization catalysed by an engineered animal cyclic guanosine-adenosine synthase (cGAS). For the thiotriphosphate synthesis, three kinase enzymes were engineered to develop a non-natural cofactor recycling system in which one thiotriphosphate serves as a cofactor in its own synthesis. This study demonstrates the substantial capacity that currently exists to use biosynthetic approaches to discover and manufacture complex, non-natural molecules., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Background and Aims: The purpose of this study was to investigate the effect of low-level laser therapy (LLLT) on radial bone fracture gap healing in a rabbit model., Materials Subjects and Methods: Thirty male white New Zealand rabbits under general anesthesia had a 3mm slice of radial bone surgically removed. Fifteen rabbits were treated by 830 nm laser at 4 J/cm 2 and 15 were used as non-treated controls. Callus development was assessed by X-ray and radiographs every 7 days for 3 weeks., Results: Significant radiologic changes were observed in both groups against time (P > 0.001) or from week to week (P > 0.05). However, there was no statistical difference in radiologic scores after week 2 (P = 0.087) or week 3 (P = 0.077) between control and laser treated bone., Conclusions: Findings suggest that in this study, laser treatment did not enhance callus formation nor reduce repair time of complete fracture of the radius in rabbits.

We introduce a previously unexplored parameter-halenium affinity (HalA)- as a quantitative descriptor of the bond strengths of various functional groups to halenium ions. The HalA scale ranks potential halenium ion acceptors based on their ability to stabilize a "free halenium ion". Alkenes in particular but other Lewis bases as well, such as amines, amides, carbonyls, and ether oxygen atoms, etc., have been classified on the HalA scale. This indirect approach enables a rapid and straightforward prediction of chemoselectivity for systems involved in halofunctionalization reactions that have multiple nucleophilic sites. The influences of subtle electronic and steric variations, as well as the less predictable anchimeric and stereoelectronic effects, are intrinsically accounted for by HalA computations, providing quantitative assessments beyond simple "chemical intuition". This combined theoretical-experimental approach offers an expeditious means of predicting and identifying unprecedented reactions.

Cantharis vesicatoria (blister beetle) is used in Chinese medicine and has been categorized as highly toxic in the Chinese pharmacopeia. In Europe, Cantharis patches have been used since ages to treat various skin-related diseases. We investigated the cytotoxicity of the Cantharis ingredient, cantharidin, in 41 tumor cell lines (Oncotest panel) and compared the results with those of 60 cell lines of the National Cancer Institute, USA. We found profound activity at low micromolar concentrations (log ₁₀IC₅₀ values between -6.980 and 5.009 M). Cantharidin bound to protein phosphatase 2A (PP2A) with higher affinity (-8.12 kcal/mol) than to PP1 (-6.25 kcal/mol) in molecular docking analyses. Using a PCR array for 84 apoptosis genes, cantharidin treatment upregulated gene expression of caspase-1 and nerve growth factor receptor, but downregulated mRNA expression of Bcl-2 like protein 10, Fas ligand, and tumor necrosis factor-α. By using COMPARE analysis of microarray-based transcriptome-wide mRNA expressions, 21 genes were found to significantly correlate with response of 60 tumor cell lines to cantharidin. As shown by hierarchical cluster analysis and chi-squared test, the distribution of cell lines in the dendrogram according to their gene expression profiles predicted sensitivity or resistance to cantharidin (P=6.482 × 10(-5)). The compassionate use of Cantharis patches in two patients suffering from basalioma and Mycosis fungoides, respectively, considerably improved the diseases without signs of toxicity. In conclusion, these results indicate that cantharidin may be a useful candidate to develop novel strategies for cancer therapy., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Regarding the importance of air pollution issue for large cities, as Tehran metropolis, many plans, programs, projects and regulations have been developed to manage urban air pollution. However, most of them failed to decline the pollution. The purpose of this study is to pathologically analyze air-pollution control plans in order to offer effective solutions for Tehran metropolis., Methods: A qualitative content analysis and a semi-structured interview with 14 practicing professionals were used to identify key causes and sources of Tehran's air pollution, to recognize challenges and obstacles towards effective performance of air-pollution control plans in this metropolitan area, and to suggest the most effective controlling solutions., Results: Challenges related to air-pollution control plans can be divided into two major categories: Firstly lack of integrated and organized stewardship and secondly those related to political, economical, social and technical environmental abbreviated as PEST, challenges. For effective control of the Tehran air pollution, the following eight controlling alternatives were identified: Systematization of plan preparation process, organizing the stewardship, standardization and utilization of new technologies and professional experts, cultural and infrastructural development, realization of social justice, developing coordination and controlling mechanisms, improving citizen's participatory capacity, and focusing on effective management of fuel and energy., Conclusions: Controlling air pollution in Tehran should be considered as a priority for policymakers to make enforcements through applying a systemic cycle of preparation effective and comprehensive plans. Further, implement the enforcements and evaluate the environmental impact of the plans through involving all stakeholders.

Background: Consequences of cerebral palsy in adulthood can affect physical, psychological capabilities and quality of life. The purpose of this study was to investigate the relationship between quality of life with spasticity and level of motor function in Iranian young adults with spastic cerebral palsy who were community dweller., Methods: In an analytical cross sectional study, 77 participants with spastic cerebral palsy (44 women, 33 men) with age range of 20 to 40 years; (mean age 26.19±5 yr) took part in this study. They were enrolled from three Raad Rehabilitation Goodwill complexes in Tehran and Karaj cities. All subjects were recruited through convenient sampling. Severity of Spasticity for knee flexors was measured with Modified Tardieu Scale. In addition, the level of motor function, and quality of life were assessed respectively through Gross Motor Function Classification System and World Health Organization Quality of life questionnaire (WHOQOL- BREF). To analyze data, Pearson and spearman correlation coefficient was used., Results: No correlation found between quality of life with knee flexor muscles spasticity and level of motor function (p> 0.05)., Conclusion: Quality of life as a multi dimensional concept has been impacted by many factors such as physical status, environmental issues and culture. Possibly, severity of spasticity and level of function have a less pronounced effect on quality of life in community dwelling adults with cerebral palsy.

This study assessed the biodistribution of autologous leucocytes radiolabelled with technetium-99m stannous fluoride colloid (99mTcSnC) for detection of foci of induced inflammation in dogs. Venous blood was collected from seven healthy dogs and incubated with 99mTcSnC for 1h at room temperature. Radiolabelled samples were injected intravenously (IV) and the dogs were scanned using a gamma camera. Another seven healthy dogs were injected intradermally with tumour necrosis factor alpha and then IV with 99mTcSnC radiolabelled autologous blood 3h later before being scanned. The radiolabelled leucocytes localised to sites of inflammation by 30 min post-injection. IV injection of autologous leucocytes radiolabelled with 99mTcSnC appears to be a sensitive method for localisation of induced foci of inflammation in dogs., (Copyright (c) 2009 Elsevier Ltd. All rights reserved.)

Technetium-99m stannous colloid (9mTcSnC) has been used to radiolabel human leukocytes to investigate various inflammatory disorders. We investigated the in vitro behavior of feline leukocytes labeled in whole blood with 99mTcSnC. Heparinized blood samples were collected from healthy cats and divided into control and test aliquots. The latter were labeled with 99mTcSnC using a standard procedure. Leukocyte viability was determined for each sample using a trypan blue exclusion test. Labeling efficiency was determined for test aliquots. Test aliquots were layered onto Histopaque-1077 and centrifuged before measurement of radioactivity of the blood components. Leukocytes from radiolabeled and control samples were washed and incubated with opsonized zymosan particles to allow assessment of phagocytic function. Aliquots were taken from radiolabeled feline leukocyte samples at 1, 3, 4, and 7 h postlabelling. After centrifugation of each aliquot, radioactivity of the supernatant and pellet was measured and the labeling retention determined. Leukocyte viability in both radiolabeled and control samples was > 98%. The labeling efficiency was 95.2 +/- 0.14%. The distribution of radioactivity in feline blood was found to be 3.4 +/- 0.18% in plasma, 39.0 +/- 0.37% in erythrocytes, and 57.6 +/- 0.38% in leukocytes. Labeled feline leukocytes had phagocytic activity of 90.9 +/- 0.18% (control 91.3 +/- 0.15%). The radiolabeled leukocytes retained 93.4 +/- 0.19% of the radioactivity up to 7h postlabeling. 99TcSnC efficiently labeled feline leukocytes with no effect on viability and minimal effect on phagocytic function. The percentage retention of radioactivity by the leukocytes was still high at 7h postlabeling.

Spinal cord injury is very complicated, as there are factors in the body that inhibit its repair. Although regeneration of the mammalian central nervous system (CNS) was once thought to be impossible, studies over the past two decades have shown that axonal growth after spinal cord injury can occur when provided with the correct substratum. Traditionally, tissue transplantation or peripheral nerve grafting are used to repair damaged or diseased regions of the CNS, but donor shortage and immunological problems associated with infectious disease are often encountered. Fortunately, recent advances in neuroscience, cell culture, and biomaterials provide optimistic future using new treatments for nerve injuries. Biomaterial scaffold creates substrate within which cells are instructed to form a tissue or an organ in a highly controlled way. The principal function of a scaffold is to direct cell behavior such as migration, proliferation, differentiation, maintenance of phenotype, and apoptosis by facilitating sensing and responding to the environment via cell-matrix and cell-cell communications. Therefore, having such abilities provides scaffolds seeded with a special type of cell as an important part of tissue engineering and regenerative medicine which spinal cord regeneration is an example of. Nevertheless, the vast number of biodegradable synthetic and natural biopolymers makes choosing the right one very difficult. In this review article, it was tried to provide an inclusive survey of biopolymers seeded with Schwann cells (SCs) to be used for axonal regeneration in the nervous system.

Introduction: Technetium-99m stannous colloid ((99m)TcSnC)-labeled leukocytes are used to investigate a variety of inflammatory diseases in human medicine. The present study investigates the in vitro behavior of canine leukocytes labeled in whole blood with (99m)TcSnC., Methods: Blood samples from 10 healthy dogs were labeled with (99m)TcSnC using a standard procedure. The distribution of radioactivity among blood components (plasma, leukocyte layers and erythrocytes) was measured following separation of the radiolabeled samples across Histopaque density gradients. Phagocytic function of labeled and unlabeled leukocytes was estimated using zymosan particles. Labeling retention by leukocytes was determined at 1, 3, 4 and 7 h postlabeling., Results: The mean+/-standard error percentage of radioactivity associated with plasma, erythrocyte and leukocyte fractions was 2.0+/-0.21%, 55.5+/-0.60% and 42.5+/-0.54%, respectively (the last comprising 70.2+/-0.83% in polymorphonuclear leukocytes and 29.8+/-0.83% in mononuclear leukocytes). Labeled canine leukocytes had a phagocytic activity of 91.3+/-0.28% (control, 91.7+/-0.26%). The radiolabeled canine leukocytes retained 94.1+/-0.30% of radioactivity at 7 h postlabeling., Conclusions: Radiolabeling of canine leukocytes in whole blood with (99m)TcSnC has minor adverse effect on their phagocytic function. The radiolabeled canine leukocytes retained a large percentage of radioactivity for at least 7 h postlabeling.