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The presented paper investigates the creation of chitosan-based composites on the surface of chemically modified poly-D-lactic acid (PDLA). PDLA was dissolved in chloroform and cast into a glass dish until the complete evaporation of the solvent. The surface of the created PDLA films was modified with 1,6-hexanediamine and glutaraldehyde for the creation of free aldehyde side groups. Composite layers of chitosan (CH) were deposited on the surface of the modified films. The mechanical properties of the composite films were investigated using a dynamometer. The surface morphology of the created composite films was studied with Scanning electron microscopy (SEM). Sessile drop method was used to determine the surface free energy of the created chitosan-based composite layers. [ABSTRACT FROM AUTHOR]

The development of 1,8-naphthalimide derivatives as cell probes, DNA targeting agents, and anti-tumor drugs is one of the research hotspots in the field of medicine. Naphthalimide compounds are a kind of DNA embedder, which can change the topological structure of DNA by embedding in the middle of DNA base pairs, and then affect the recognition and action of topoisomerase on DNA. Aminofide and mitonafide are the first 2 drugs to undergo clinical trials. They have good DNA insertion ability, can embed DNA double-stranded structure, and induce topoisomerase II to cut part of pBR322DNA, but not yet entered the market due to their toxicity. In this paper, the design and structure-activity relationship of mononaphthalimide and bisaphthalimide compounds were studied, and the relationship between the structure of naphthalimide and anti-tumor activity was analyzed and discussed. It was found that a variety of structural modifications were significant in improving anti-tumor activity and reducing toxicity. [ABSTRACT FROM AUTHOR]

Supramolecular gels with metal ion-responsiveness are an important kind of smart materials due to their potential application in environmental monitoring. In this study, a novel l -glutamine-contained 1,8-naphthalimide derivative (NDG) has been designed and synthesized as an organogelator. NDG could self-assemble into stable supramolecular organogels in different kind of solvents, and the gelation process showed bright blue aggregation-induced emission (AIE). The self-assembly behavior, morphology and structure of NDG gels were thoroughly studied by various techniques. Interestingly, the obtained NDG organogel exhibited a fluorescence "turn-off" response for Fe3+ and formed a stable metallogel NDG -Fe3+. The detection limit (LOD) of NDG in diluted solution and gel states for Fe3+ was calculated to be 30.8 nM and 11.5 nM, respectively, indicating high sensitivity. In addition, the blue fluorescence emission of the gel system was restored in the presence of ascorbic acid and then quenched again with oxygen, which showed reversible fluorescence sensing effect and employed as a logic gate at the molecular level. Furthermore, xerogel-based film of NDG emitted strong blue emission and could be utilized as paper-based chemosensor to detect Fe3+. And also, the NDG gel had potential application in fluorescence display material. [Display omitted] • A l -glutamine-contained 1,8-naphthalimide gelator was synthesized with AIE effect. • The organogel exhibited a fluorescence response for Fe3+ by gel-gel transition. • The gel system was potentially constructed as a molecular logic gate. • Paper-based gel film was used in Fe3+ recognition and as display material. [ABSTRACT FROM AUTHOR]

Synthesis of the 1,3-dienes from arylboronic acids with propargyl alcohols using a Ni(II) precatalysts is presented. Through detailed reaction screening NiCl2(PCy3)2 has been identified as the optimal catalyst for this transformation. The reaction is thought to proceed through a Ni(II) allenyl complex, which undergoes a base free Suzuki-Miyaura cross-coupling through arylboronic acids, with the resultant aryl allene rearranging to its 1,3-diene. Application of these optimized reaction conditions then provides several dienes in reasonable to good, isolated yields. [ABSTRACT FROM AUTHOR]

At the RoboCup, a robotics soccer tournament, the Small Size League (SSL) is one of its leagues. The thought of a mechanism in this league that could perform unpredictable kicks and passes inspired study into both the physical mechanism required to do it and the algorithms needed to make the most of it.By introducing new ideas and utilizing a Deep Neural Network, this work contributes by improving a prior algorithm that aims to carry out a real-time inversion of the non-linear ordinary differential equation (ODE) that models the ball’s path in order to determine the parameters to hit a target with a curved kick mechanism (DNN). New techniques are also presented. The two suggested DNN achieved accuracy levels of more than 92% in the outcomes of simulation runs in MATLAB. [ABSTRACT FROM AUTHOR]

Introduction: 24-Hydroxylase, encoded by the CYP24A1 gene, is a crucial enzyme involved in the catabolism of vitamin D. Loss-of-function mutations in CYP24A1 result in PTH-independent hypercalcaemia with high levels of 1,25(OH) 2D3. The variety of clinical manifestations depends on age, and underlying genetic predisposition mutations can lead to fatal infantile hypercalcaemia among neonates, whereas adult symptoms are usually mild. Aim of the study: We report a rare case of an adult with primary hyperparathyroidism and loss-of-function mutations in the CYP24A1 gene and a review of similar cases. Case presentation: We report the case of a 58-year-old woman diagnosed initially with primary hyperparathyroidism. Preoperatively, the suspected mass adjoining the upper pole of the left lobe of the thyroid gland was found via ultrasonography and confirmed by 99mTc scintigraphy and biopsy as the parathyroid gland. The patient underwent parathyroidectomy (a histopathology report revealed parathyroid adenoma), which led to normocalcaemia. After 10 months, vitamin D supplementation was introduced due to deficiency, and the calcium level remained within the reference range. Two years later, biochemical tests showed recurrence of hypercalcaemia with suppressed parathyroid hormone levels and elevated 1,25(OH)2D3 concentrations. Further investigation excluded the most common causes of PTH-independent hypercalcaemia, such as granulomatous disease, malignancy, and vitamin D intoxication. Subsequently, vitamin D metabolites were measured using LC-MS/MS, which revealed high levels of 25(OH)D3, low levels of 24,25(OH)2D3 and elevated 25(OH)2D3/24,25 (OH)2D3 ratios, suggesting a defect in vitamin D catabolism. Molecular analysis of the CYP24A1 gene using the NGS technique revealed two pathogenic variants: p.(Arg396Trp) and p.(Glu143del) (rs114368325 and rs777676129, respectively). Conclusions: The diagnostic process for hypercalcaemia becomes complicated when multiple causes of hypercalcaemia coexist. The measurement of vitamin D metabolites using LC-MS/MS may help to identify carriers of CYP24A1 mutations. Subsequent molecular testing may contribute to establishing the exact frequency of pathogenic variants of the CYP24A1 gene and introducing personalized treatment. [ABSTRACT FROM AUTHOR]

This article covers almost 130 Pt(ii) complexes with an inner coordination sphere of cis-PtP2Cl2. The P-donor ligands are organodiphosphines that create four-, five-, and six-membered metallocyclic rings. There are two types of four-membered rings: PCP and PNCP, and four types of five-membered rings: PC–CP, PC═CP, PNNP, and PCOP. There are wide varieties of the six-membered metallocyclic rings: PC3P (most common), PCNCP, PCSCP, PCSiCP, PNCNP, PCCOP, PCCNP, POPNP, POSiOP, P(CNC)2P, and P(CNC)(CCC)P. The P–Pt–P bite angles open with the size of the metallocyclic rings in the order (total mean values 72.4° [PXP] < 86.4° [PXXP] < 94.0° [PXXNP]). There are complexes that are examples of distortion and ligand isomerism. The structural data are analyzed and discussed. [ABSTRACT FROM AUTHOR]