Aptamer-based electrochemical biosensing strategy toward human non-small cell lung cancer using polyacrylonitrile/polypyrrole nanofibers.

In the present study, a sensitive electrochemical aptamer-based biosensing strategy for human non-small cell lung cancer (NSCLC) detection was proposed using nanofiber-modified disposable pencil graphite electrodes (PGEs). The composite nanofiber was comprised of polyacrylonitrile (PAN) and polypyrrole (PPy) polymers, and fabrication of the nanofibers was accomplished using electrospinning process onto PGEs. Development of the nanofibers was confirmed using scanning electron microscopy (SEM). The high-affinity 5'-aminohexyl-linked aptamer was immobilized onto a PAN/PPy composite nanofiber-modified sensor surface via covalent bonding strategy. After incubation with NSCLC living cells (A549 cell line) at 37.5 °C, the recognition between aptamer and target cells was monitored by electrochemical impedance spectroscopy (EIS). The selectivity of the aptasensor was evaluated using nonspecific human cervical cancer cells (HeLa) and a nonspecific aptamer sequence. The proposed electrochemical aptasensor showed high sensitivity toward A549 cells with a detection limit of 1.2 × 103 cells/mL. The results indicate that our label-free electrochemical aptasensor has great potential in the design of aptasensors for the diagnostics of other types of cancer cells with broad detection capability in clinical analysis. Graphical abstract.

Novel regulation mechanism of adrenal cortisol and DHEA biosynthesis via the endogen ERAD inhibitor small VCP-interacting protein.

Endoplasmic reticulum-associated degradation (ERAD) is a well-characterized mechanism of protein quality control by removal of misfolded or unfolded proteins. The tight regulation of ERAD is critical for protein homeostasis as well as lipid metabolism. Although the mechanism is complex, all ERAD branches converge on p97/VCP, a key protein in the retrotranslocation step. The multifunctionality of p97/VCP relies on its multiple binding partners, one of which is the endogenous ERAD inhibitor, SVIP (small VCP-interacting protein). As SVIP is a promising target for the regulation of ERAD, we aimed to assess its novel physiological roles. We revealed that SVIP is highly expressed in the rat adrenal gland, especially in the cortex region, at a consistently high level during postnatal development, unlike the gradual increase in expression seen in developing nerves. Steroidogenic stimulators caused a decrease in SVIP mRNA expression and increase in SVIP protein degradation in human adrenocortical H295R cells. Interestingly, silencing of SVIP diminished cortisol secretion along with downregulation of steroidogenic enzymes and proteins involved in cholesterol uptake and cholesterol biosynthesis. A certain degree of SVIP overexpression mainly increased the biosynthesis of cortisol as well as DHEA by enhancing the expression of key steroidogenic proteins, whereas exaggerated overexpression led to apoptosis, phosphorylation of eIF2α, and diminished adrenal steroid hormone biosynthesis. In conclusion, SVIP is a novel regulator of adrenal cortisol and DHEA biosynthesis, suggesting that alterations in SVIP expression levels may be involved in the deregulation of steroidogenic stimulator signaling and abnormal adrenal hormone secretion.

Design, Synthesis and Evaluation of the Biological Activities of Some New Carbohydrazide and Urea Derivatives.

OBJECTIVES: Urea and carbohydrazide derivatives are important compounds exhibiting cytotoxic activities. In this study, a series of new urea and carbohydrazide derivatives containing an pyridine ring were synthesized and evaluated for cytotoxic activity. MATERIALS AND METHODS: The proposed structures of the synthesized compounds were confirmed using elemental analysis, IR, and 1H-NMR spectroscopic techniques. The cytotoxic potencies of synthesized compounds were determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT) on BRCA mutant-carrying HCC1937 and Capan-1 cell lines, as well as on MCF7, HeLa, and MRC5 cells. RESULTS: 3a, 3b, 3c and 3d showed cytotoxic activity against all cancer cell lines. CONCLUSION: Our data indicate that compounds 3a-d are more selective to cancer cells compared with nontumoral fibroblasts; however, these compounds are not more potent on HR defective cells with BRCA mutants.

Synthesis and evaluation of pyridinium-hydrazone derivatives as potential antitumoral agents.

The hydrazones of 4-hydrazinylpyridinium bearing alkylphenyl groups on pyridinium nitrogen were synthesized and evaluated for their cytotoxic activity against MCF-7, PC3, U2OS, and HEK293 cell lines by Wst1 cell proliferation assay. Cytotoxic activity results indicated that d derivatives having butylene chain; 4 and 5 series having naphthalene and anthracene ring systems showed high cytotoxic activity (IC50  = 3.27-8.54 µm) on cancer cells. 3d (4-(2-(4-hydroxybenzylidene)hydrazinyl)-1-(4-phenylbutyl)pyridinium bromide) was the most cytotoxic compound with IC50 value of 3.27 µm against MCF-7. The most active derivatives (1d, 2d, 3d, 4, and 5 series) were selected to investigate for the effects on autophagy by analyzing the expression of autophagy marker proteins. The conversion of LC3-I to its lipidated form LC3-II is essential for autophagy and related to autophagosomes. According to our results, all tested compounds except for 3d induced lipidated form LC3-II accumulation. Then, the effects of the compounds on p62 protein level were also analyzed by the immunoblotting as the autophagy inhibition results in accumulation of p62. Further molecular mechanistic studies including morphological analysis and live-death assays indicated that all tested compounds (1d, 2d, 3d, 4, and 5 series) are potent antitumoral molecules and all except for 3d have potential to inhibit autophagic flux.

Comparison of anterior and lateral approaches in the treatment of extension-type supracondylar humerus fractures in children.

Eighty-four patients who underwent open reduction and Kirschner wire (K-wire) fixation for supracondylar humerus fractures through anterior or lateral approach with or without additional medial incisions were compared with regard to complications and end results. A total of 46 patients were operated through the anterior and 38 through the lateral approach. In lateral approach cases, medial incision was added only in those patients in whom the medial condyle and therefore the ulnar nerve were not easily distinguished due to excessive oedema. All the fractures were Gartland type III extension fractures. The patient series was consecutive, and lateral approach had a longer follow-up of 89 months (70-134 months); the incision protocol was changed approximately mid-series to the anterior approach, and therefore a shorter follow-up time of only 50 months (24-84 months) was possible. All patients were treated according to the same postoperative protocol. A follow-up examination was performed and all the patients were evaluated according to Flynn's criteria; loss of flexion or extension clinically, any deviation of the carrying angle radiologically, and the appearance of the incision scar were evaluated. According to the above parameters, results were excellent in 19, good in 18, and fair in one in the lateral incision group, whereas in the anterior incision group, excellent results were obtained in 31 patients and good results in 15 of them. Cosmetically, two patients in the lateral incision group had hypertrophic scar tissue, whereas the anterior incisions were barely noticeable as they were included into the flexion crease. In conclusion, we can say that anterior incision when open reduction is needed in pediatric supracondylar fractures offer the advantage of a smaller scar and easy access to structures that might be injured between the fractured fragments.