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Nanoparticles made of porous coordination polymers, known as metal‐organic frameworks (MOFs), are becoming increasingly popular in nanomaterials research, especially in catalytic applications. With their intricate architectures, MOFs make it possible to incorporate metal nodes, encapsulate substrates, and use functional linkers, all of which contribute to synergistic engineering. A Ni‐based metal‐organic framework sample was prepared by the solvothermal method with NiCl2.6H2O as a precursor of Ni metal and terephthalic (H2BDC) acid as a linker. The as‐synthesized NiBDC was verified by X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FT‐IR), scanning electron microscopy (SEM), scanning electron microscopy with energy dispersive X‐ray spectroscopy (SEM‐EDX), transmission electron microscopy (TEM), and N2 adsorption/desorption isotherms. Based on these findings, we applied the as‐synthesized NiBDC to the oxidative coupling reaction of benzylamine. The results revealed that with NiBDC as a heterogeneous catalyst, the oxidative coupling reaction of benzylamine achieved a performance of 92%. Furthermore, the catalyst maintains good stability after four catalytic cycles, with an efficiency of approximately 82%. [ABSTRACT FROM AUTHOR]

Purpose: Eosinophilic gastrointestinal diseases represent a rare and diverse group of conditions. Given that the pathogenesis of EoC is not well understood and is often linked to allergic conditions, this case underscores the necessity for further research into such unique presentations. The patient's prolonged gastrointestinal symptoms presented a significant diagnostic challenge, emphasizing the importance of ruling out various potential causes for elevated blood eosinophils. This exploration aims to enhance the understanding of such rare clinical scenarios and improve diagnostic accuracy in similar cases. Case Description: We present a unique case of a 57-year-old patient with a medical history of asthma and allergic rhinitis who presented recurrent abdominal pain, significant blood eosinophilia, and elevated levels of Immunoglobulin G4. After ruling out hematological and secondary causes of eosinophilia, a biopsy of the colon mucosa revealed an excess of tissue eosinophils, confirming the diagnosis of EoC. The patient responded well to corticosteroids and was subsequently maintained on montelukast, with no recurrence of symptoms over 3 months. Conclusion: This rare confluence of EoC, asthma, and high levels of serum IgG4 in a single patient contributes to our understanding of these complex and interconnected disorders. [ABSTRACT FROM AUTHOR]

Amyloid β-protein (Aβ) assembly is a seminal process in Alzheimer's disease. Elucidating the mechanistic features of this process is thought to be vital for the design and targeting of therapeutic agents. Computational studies of the most pathologic form of Aβ, the 42-residue Aβ42 peptide, have suggested that hydrogen bonding involving Ser26 may be particularly important in organizing a monomer folding nucleus and in subsequent peptide assembly. To study this question, we experimentally determined structure-activity relationships among Aβ42 peptides in which Ser26 was replaced with Gly, Ala, α-aminobutryic acid (Abu), or Cys. We observed that aliphatic substitutions (Ala and Abu) produced substantially increased rates of formation of β-sheet, hydrophobic surface, and fibrils, and higher levels of cellular toxicity. Replacement of the Ser hydroxyl group with a sulfhydryl moiety (Cys) did not have these effects. Instead, this peptide behaved like native Aβ42, even though the hydropathy of Cys was similar to that of Abu and very different from that of Ser. We conclude that H bonding of Ser26 is the factor most important in its contribution to Aβ42 conformation, assembly, and subsequent toxicity.

Lutein is a macular biopigment that can protect the retina from oxidative stress induced by chronic exposure to light and oxidants. The peel of gac fruit (Momordica cochinchinensis) contains high levels of lutein, but the extraction optimisation parameters are complex, requiring saponification, and the effects on ocular bioactivity are not well understood. This study is aimed at optimising parameters for lutein extraction validated using HPLC from gac peel to determine their protective effects on oxidatively stressed retinal cells. The factors investigated for optimisation were KOH concentration, time, and temperature using (1) single factor, (2) multiple factor response surface methodology, and (3) predictive modelling. The optimum conditions for lutein extraction using single factors were 9% KOH for 3 h at 60°C, multiple factors were 9% KOH for 3 h at 45°C, and predictive modelling was 18% KOH for 1.9 h at 39.9°C, with the maximum extraction of lutein at 12.37, 15.64, and 17.4 mg/g DW, respectively. The extracted lutein purity and chemical composition were compared using HPLC and FTIR and indicated high purity and similarities in all extracts including the commercially purified lutein. Lutein extracted exhibited benefits on oxidatively stressed retinal pigment epithelium (RPE) cells that reversed damage to baseline unstressed levels exceeding 80% viability, similar to purified lutein standards. The feasibility of gac lutein and extraction optimisation were discussed for commercial translational opportunities as a medicinal bioproduct with a focus on eye benefits. [ABSTRACT FROM AUTHOR]

Background: Terbinafine is widely used to treat onychomycosis caused by dermatophyte fungi. Terbinafine resistance in recent years is causing concern. Resistance has so far been associated with single‐nucleotide substitutions in the DNA sequence of the enzyme squalene epoxidase (SQLE) but how this affects SQLE functionality is not understood. Objectives: The aim of this study was to understand newly discovered resistance in two Australian strains of Trichophyton interdigitale. Patients/Methods: Resistance to terbinafine was tested in four newly isolated strains. Three‐dimensional SQLE models were prepared to investigate how the structure of their SQLE affected the binding of terbinafine. Results: This study found the first Australian occurrences of terbinafine resistance in two T. interdigitale strains. Both strains had novel deletion mutations in erg1 and frameshifts during translation. Three‐dimensional models had smaller SQLE proteins and open reading frames as well as fewer C‐terminal α‐helices than susceptible strains. In susceptible strains, the lipophilic tail of terbinafine was predicted to dock stably into a hydrophobic pocket in SQLE lined by over 20 hydrophobic amino acids. In resistant strains, molecular dynamics simulations showed that terbinafine docking was unstable and so terbinafine did not block squalene metabolism and ultimately ergosterol production. The resistant reference strain ATCC MYA‐4438 T. rubrum showed a single erg1 mutation that resulted in frameshift during translation, leading to C‐terminal helix deletion. Conclusions: Modelling their effects on their SQLE proteins will aid in the design of potential new treatments for these novel resistant strains, which pose clinical problems in treating dermatophyte infections with terbinafine. [ABSTRACT FROM AUTHOR]

A popular working hypothesis of Alzheimer's disease causation is amyloid β-protein oligomers are the key neuropathogenetic agents. Rigorously elucidating the role of oligomers requires the production of stable oligomers of each size. We previously used zero-length photochemical cross-linking to allow stabilization, isolation, and determination of structure-activity relationships of pure populations of Aβ40 dimers, trimers, and tetramers. We also attempted to study Aβ42 but found that Aβ42 oligomers subjected to the same procedures were not completely stable. On the basis of the fact that Tyr is a critical residue in cross-linking chemistry, we reasoned that the chemical accessibility of Tyr10 in Aβ42 must differ from that in Aβ40. We thus chemically synthesized four singly substituted Tyr variants that placed the Tyr in different positions across the Aβ42 sequence. We then studied the stability of the resulting cross-linked oligomers as well as procedures for fractionating the oligomers to obtain pure populations of different sizes. We found that [Phe(10),Tyr(42)]Aβ42 produced stable oligomers yielding highly pure populations of dimers through heptamers. This provides the means to establish formal structure-activity relationships of these important Aβ42 assemblies. In addition, we were able to analyze the dissociation patterns of non-cross-linked oligomers to produce a model for oligomer formation. This work is relevant to the determination of structure-activity relationships that have the potential to provide mechanistic insights into disease pathogenesis.

Background and Aim: Accurate prediction of severe acute pancreatitis (SAP) is crucial for timely intervention. This study focuses on the Systemic Inflammatory Response Index (SIRI) to assess its clinical value in predicting the severity of AP in the Vietnamese context. Methods: A cross‐sectional prospective study was conducted with acute pancreatitis patients at a national hospital in Ho Chi Minh City. The patients were classified into nonsevere and severe groups, and the clinical characteristics were analyzed. The predictive abilities of SIRI, calculated using neutrophil × monocyte/lymphocyte, was assessed for predictive abilities. Multivariate regression and receiver operating characteristics (ROC) curves evaluated the prognostic factors and predictive accuracy. Results: Among 207 patients, 78.7% had nonsevere AP, and 21.3% had SAP. The severe group exhibited a significantly higher median SIRI (12.0) than the nonsevere group (4.9) (P < 0.001). Multivariate regression identified SIRI (odds ratio [OR] = 1.623) as an independent predictor of SAP. The ROC curve determined a SIRI cutoff of 7.82 with an area under the curve (AUC) of 0.737. Combining the SIRI and Bedside Index for Severity in Acute Pancreatitis (BISAP) score improved the predictive ability (AUC = 0.820) with increased sensitivity (90.91%) (P < 0.001). Conclusion: SIRI, particularly when combined with the BISAP score, shows significant potential to predict SAP severity in the Vietnamese clinical setting, providing valuable information for effective patient management. [ABSTRACT FROM AUTHOR]