5-aminolevulinic acid-based photodynamic therapy in combination with antifungal agents for adult kerion and facial ulcer caused by Trichophyton rubrum.

Dermatophytosis is the most common fungal infectious disease in the world, which is commonly caused by Trichophyton rubrum in China. The traditional therapies for treating dermatophytosis include topical and oral antifungal agents like terbinafine, griseofulvin, and azole antifungal drugs. However, 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT) as a new alternative therapy avoids the side effects and drug resistance of traditional antifungal agents. We report two cases diagnosed as kerion and tinea faciei secondary to ulcers with CARD 9 deficiency, both of whom were infected by T.rubrum. They were both successfully treated by ALA-PDT combined with antifungal drugs, providing a feasible strategy for therapeutic choice for adult kerion and ulcer treatment.

A Novel 3D Culture Scaffold to Shorten Development Time for Multicellular Tumor Spheroids.

Multicellular tumor spheroids and tumoroids are considered ideal in vitro models that reflect the features of the tumor microenvironment. Biomimetic components resembling the extracellular matrix form scaffolds to provide structure to 3-dimensional (3D) culture systems, supporting the growth of both spheroids and tumoroids. Although Matrigel has long been used to support 3D culture systems, batch variations, component complexity, and the use of components derived from tumors are complicating factors. To address these issues, we developed the ACD 3D culture system to provide better control and consistency. We evaluated spheroid and tumoroid formation using the ACD 3D culture system, including the assessment of cell viability and cancer marker expression. Under ACD 3D culture conditions, spheroids derived from cancer cell lines exhibited cancer stem cell characteristics, including a sphere-forming size and the expression of stem cell marker genes. The ACD 3D culture system was also able to support patient-derived primary cells and organoid cell cultures, displaying adequate cell growth, appropriate morphology, and resistance to oxaliplatin treatment. These spheroids could also be used for drug screening purposes. In conclusion, the ACD 3D culture system represents an efficient tool for basic cancer research and therapeutic development.

Conformational Characterization of Native and L17A/F19A-Substituted Dutch-Type ß-Amyloid Peptides.

Some mutations which occur in the α/ß-discordant region (resides 15 to 23) of ß-amyloid peptide (Aß) lead to familial Alzheimer's disease (FAD). In vitro studies have shown that these genetic mutations could accelerate Aß aggregation. We recently showed that mutations in this region could alter the structural propensity, resulting in a different aggregative propensity of Aß. Whether these genetic mutations display similar effects remains largely unknown. Here, we characterized the structural propensity and aggregation kinetics of Dutch-type Aß40 (Aß40(E22Q)) and its L17A/F19A-substituted mutant (Aß40(L17A/F19A/E22Q)) using circular dichroism spectroscopy, nuclear magnetic spectroscopy, and thioflavin T fluorescence assay. In comparison with wild-type Aß40, we found that Dutch-type mutation, unlike Artic-type mutation (E22G), does not reduce the α-helical propensity of the α/ß-discordant region in sodium dodecyl sulfate micellar solution. Moreover, we found that Aß40(L17A/F19A/E22Q) displays a higher α-helical propensity of the α/ß-discordant region and a slower aggregation rate than Aß40(E22Q), suggesting that the inhibition of aggregation might be via increasing the α-helical propensity of the α/ß-discordant region, similar to that observed in wild-type and Artic-type Aß40. Taken together, Dutch-type and Artic-type mutations adopt different mechanisms to promote Aß aggregation, however, the L17A/F19A mutation could increase the α-helical propensities of both Dutch-type and Artic-type Aß40 and inhibit their aggregation.

Characterization of the interactions between inhibitor-1 and recombinant PP1 by NMR spectroscopy.

Inhibitor-1 is converted into a potent inhibitor of native protein phosphatase-1 (PP1) when Thr35 is phosphorylated by cAMP-dependent protein kinase (PKA). However, PKA-phosphorylated form of inhibitor-1 displayed a weak activity in inhibition of recombinant PP1. The mechanism for the impaired activity of PKA-phosphorylated inhibitor-1 toward inhibition of recombinant PP1 remained elusive. By using NMR spectroscopy in combination with site-directed mutagenesis and inhibitory assay, we found that the interaction between recombinant PP1 and the consensus PP1-binding motif of PKA-thiophosphorylated form of inhibitor-1 was unexpectedly weak. Unlike binding to native PP1, the subdomains 1 (residues around and including the phosphorylated Thr35) and 2 (the consensus PP1-binding motif) of PKA-thiophosphorylated form of inhibitor-1 do not exhibit a synergistic effect in inhibition of recombinant PP1. This finding implied that a slight structural discrepancy exists between native and recombinant PP1, resulting in PKA-thiophosphorylated form of inhibitor-1 displaying a different affinity to native and recombinant enzyme.

L17A/F19A Substitutions Augment the α-Helicity of ß-Amyloid Peptide Discordant Segment.

ß-amyloid peptide (Aß) aggregation has been thought to be associated with the pathogenesis of Alzheimer's disease. Recently, we showed that L17A/F19A substitutions may increase the structural stability of wild-type and Arctic-type Aß40 and decrease the rates of structural conversion and fibril formation. However, the underlying mechanism for the increase of structural stability as a result of the alanine substitutions remained elusive. In this study, we apply nuclear magnetic resonance and circular dichroism spectroscopies to characterize the Aß40 structure, demonstrating that L17A/F19A substitutions can augment the α-helicity of the residues located in the α/ß-discordant segment (resides 15 to 23) of both wild-type and Arctic-type Aß40. These results provide a structural basis to link the α-helicity of the α/ß-discordant segment with the conformational conversion propensity of Aß.

Crosstalk between activated forms of the aryl hydrocarbon receptor and glucocorticoid receptor.

Pyrene, benzo[a]pyrene (BaP), and indeno[1,2,3-cd]pyrene (IND) are poly cyclic aromatic hydrocarbons (PAHs) with four to six annealed phenyl rings. Dexamethasone (Dex) is a synthetic agonist of glucocorticoids. The aryl hydrocarbon receptor (AhR) ligands, BaP and IND, did not directly activate the glucocorticoid receptor (GR), and Dex did not activate the AhR either. Whenever BaP and IND were added to Dex-treated cultures, they were present with Dex for longer periods, and higher enhancement of Dex-induced transactivation of the GR was found, which indicates that the freshly activated AhR is essential for synergistic interactions with the activated GR. The degree of enhancement of Dex-induced transactivation of the GR by PAHs, BaP approximately IND>pyrene, paralleled the potency of PAHs in activating the AhR. This synergistic interaction was more distinct in ovarian granulosa cells (HO23) than in HepG2, 293T, or HeLa cells. In contrast, Dex suppressed AhR-mediated expressions, including AhR and cytochrome P450 (CYP) 1 A1 expressions. Dex also counteracted the BaP-induced decrease in cell viability. Crosstalk between the AhR and GR was independent of their expression levels. We concluded that the AhR functionally cross-reacts with the GR, through which transactivation activity of the GR is further enhanced, and in contrast, transactivation activity of the AhR is inhibited. This report shows the significance of in vitro endocrine-related results, which provide a clue for molecular studies of an interactive mechanism between the AhR and GR, and should be confirmed by future in vivo studies.