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Purpose: Congenital deafness not only delays auditory development but also hampers the ability to perceive nonspeech and speech signals. This study aimed to use auditory event-related potentials to explore the mismatch negativity (MMN), P3a, negative wave (Nc), and late discriminative negativity (LDN) components in children with and without hearing loss. Method: Nineteen children with normal hearing (CNH) and 17 children with hearing loss (CHL) participated in this study. Two sets of pure tones (1 kHz vs. 1.1 kHz) and lexical tones (/ba2/ vs. /ba4/) were used to examine the auditory discrimination process. Results: MMN could be elicited by the pure tone and the lexical tone in both groups. The MMN latency elicited by nonspeech and speech was later in CHL than in CNH. Additionally, the MMN latency induced by speech occurred later in the left than in the right hemisphere in CNH, and the MMN amplitude elicited by speech in CHL produced a discriminative deficiency compared with that in CNH. Although the P3a latency and amplitude elicited by nonspeech in CHL and CNH were not significantly different, the Nc amplitude elicited by speech performed much lower in CHL than in CNH. Furthermore, the LDN latency elicited by nonspeech was later in CHL than in CNH, and the LDN amplitude induced by speech showed higher dominance in the right hemisphere in both CNH and CHL. Conclusion: By incorporating nonspeech and speech auditory conditions, we propose using MMN, Nc, and LDN as potential indices to investigate auditory perception, memory, and discrimination.

Introduction: Acute lymphoblastic leukaemia (ALL) is the most common type of childhood leukaemia with effective chemotherapeutic treatment. However, obesity has been associated with higher ALL chemoresistance rates and lower event‐free survival rates. The molecular mechanism of how obesity promotes chemotherapy resistance is not well delineated. Objectives: This study evaluated the effect of adipocyte maturation on sequestration and metabolism of chemotherapeutic drug daunorubicin (DNR). Methods: Using targeted LC‐MS/MS multi‐analyte assay, DNR sequestration and metabolism were studied in human preadipocyte and adipocyte cell lines, where expressions of DNR‐metabolizing enzymes aldo‐keto reductases (AKR) and carbonyl reductases (CBR) were also evaluated. In addition, to identify the most DNR‐metabolizing AKR/CBR isoforms, recombinant human AKR and CBR enzymes were subject to DNR metabolism. The results were further validated by AKR‐, CBR‐specific inhibitors. Results: This report shows that adipocyte maturation upregulates expressions of AKR and CBR enzymes (by 4‐ to 60‐ folds, p <.05), which is positively associated with enhanced sequestration and metabolism of DNR in adipocytes compared to preadipocytes (by ~30%, p <.05). In particular, adipocyte maturation upregulates AKR1C3 and CBR1, which are the predominate metabolic enzyme isoforms responsible for DNR biotransformation to its metabolites. Conclusion: Fat is an expandable tissue that can sequester and detoxify DNR when stimulated by obesity, likely through the upregulation of DNR‐metabolizing enzymes AKR1C3 and CBR1. Our data partially explains why obese ALL patients may be more likely to become chemoresistant towards DNR, and provides evidence for potential clinical investigation targeting obesity to reduce DNR chemoresistance. [ABSTRACT FROM AUTHOR]

Flow around a near-wall circular cylinder with the splitter plate is numerically performed at Reynolds number of 500, with the objective of investigating the wake characteristics and hydrodynamic forces. Five gap ratios G ∕ D = 0. 1 , 0. 3 , 0. 5 , 0. 7 and 0. 9 (G is the gap between the lower surface of the cylinder and the wall, D is the diameter of the cylinder) are selected, and the splitter plate length L ∕ D ranges from 0 to 4. 5. The flow characteristics of an isolated cylinder with the splitter plate are investigated first for comparison, and four wake flow modes are observed, which include 2S mode (L ∕ D ≤ 0. 1 5), P+S mode (0. 3 ≤ L ∕ D ≤ 1. 0), 2S+S mode (1. 2 5 ≤ L ∕ D ≤ 2. 0) and 2P mode (L ∕ D ≥ 3. 0). As L ∕ D increases from 0 to 0. 7 5 , the mean drag coefficient ( C D ¯) is decreased, and there is a slight increase of C D ¯ for 0. 7 5 < L ∕ D ≤ 1. 2 5. In addition, the cases of L ∕ D = 0. 7 5 and L ∕ D = 1. 0 produce a very significant reduction of drag, and the C D ¯ is reduced by as much as 3 9 % and 3 8 % , respectively. The wake characteristics and hydrodynamic forces of a near-wall cylinder with the splitter plate are investigated in detail, and five wake regimes are observed, which include the wake vortex merging regime I, merged vortex attaching regime II, steady flow regime III, wall shear layer elongation regime IV and upper shear layer attaching regime V. For G ∕ D = 0. 1 , the wake vortex shedding is suppressed. For G ∕ D ≥ 0. 3 , the Strouhal number (St) is decreased as L ∕ D increases from 0 to 1.0, and there is an increase of St at L ∕ D = 1. 2 5. At L ∕ D ≥ 1. 2 5 , the St of the near-wall cylinder is larger than that of the isolated cylinder, and the increase in St is affected by the deflected gap flow. What is more, the hydrodynamic characteristics are affected by the wall. For G ∕ D > 0. 1 , the variations of C D ¯ with L ∕ D are similar to that of the isolated cylinder. It is found that the cases of L ∕ D = 0. 7 5 and L ∕ D = 1. 0 still produce a significant reduction of drag for G ∕ D > 0. 3 , and the C D ¯ is increased for all cases of L ∕ D as G ∕ D increases. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effects of myelin- and lymphocyte-associated protein (MAL) gene knockout on the morphological structure of lung tissue and the expression of E-cadherin (E-cad) and alpha-smooth muscle actin (α-SMA) in an asthmatic mouse model. Methods: Twenty-four specific pathogen-free (SPF) C57BL/6J mice were divided into four groups: the wild-type normal (WT/SAL), wild-type asthmatic (WT/OVA), gene knockout normal (MAL-/-/SAL), and gene knockout asthmatic (MAL-/-/OVA) groups. The establishment of the asthma mouse models was confirmed by evaluating behavioral symptoms and histopathological H&E and Masson staining. Western blotting and RT–qPCR were used to measure E-cad and α-SMA expression levels in lung tissues. Results: H&E staining of mouse lung tissues from WT/OVA, MAL-/-/SAL, and MAL-/-/OVA groups revealed a thickened bronchial wall, irregular lumen edge, locally fallen mucosal epithelium, and inflammatory cell infiltration compared with those of the WT/SAL group. In the WT and MAL-/- groups, the proportion of Masson-stained tissues in the OVA group was greater than that in the SAL group (p < 0.05). Compared with those in the WT/SAL group, the expression levels of α-SMA mRNA and protein were increased, while those of E-cad were decreased in the WT/OVA group (p < 0.01). Similarly, compared with those in the MAL-/-/SAL group, the expression levels of E-cad mRNA and protein were increased, while those of α-SMA were decreased in the MAL-/-/OVA group (p < 0.01). All these differences were statistically significant (p < 0.01). Conclusions: The MAL gene contributes to EMT inhibition and the stability of the airway barrier under normal physiological conditions by regulating E-cad and α-SMA expression. [ABSTRACT FROM AUTHOR]