The role of carrier spectral composition in the perception of musical pitch.

Temporal envelope fluctuations of natural sounds convey critical information to speech and music processing. In particular, musical pitch perception is assumed to be primarily underlined by temporal envelope encoding. While increasing evidence demonstrates the importance of carrier fine structure to complex pitch perception, how carrier spectral information affects musical pitch perception is less clear. Here, transposed tones designed to convey identical envelope information across different carriers were used to assess the effects of carrier spectral composition to pitch discrimination and musical-interval and melody identifications. Results showed that pitch discrimination thresholds became lower (better) with increasing carrier frequencies from 1k to 10k Hz, with performance comparable to that of pure sinusoids. Musical interval and melody defined by the periodicity of sine- or harmonic complex envelopes across carriers were identified with greater than 85% accuracy even on a 10k-Hz carrier. Moreover, enhanced interval and melody identification performance was observed with increasing carrier frequency up to 6k Hz. Findings suggest a perceptual enhancement of temporal envelope information with increasing carrier spectral region in musical pitch processing, at least for frequencies up to 6k Hz. For carriers in the extended high-frequency region (8-20k Hz), the use of temporal envelope information to music pitch processing may vary depending on task requirement. Collectively, these results implicate the fidelity of temporal envelope information to musical pitch perception is more pronounced than previously considered, with ecological implications.

Endophytic Colletotrichum (Sordariomycetes, Glomerellaceae) species associated with Citrusgrandis cv. "Tomentosa" in China.

Colletotrichum species are well-known plant pathogens, saprobes, endophytes, human pathogens and entomopathogens. However, little is known about Colletotrichum as endophytes of plants and cultivars including Citrusgrandis cv. "Tomentosa". In the present study, 12 endophytic Colletotrichum isolates were obtained from this host in Huazhou, Guangdong Province (China) in 2019. Based on morphology and combined multigene phylogeny [nuclear ribosomal internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (gapdh), chitin synthase 1 (chs-1), histone H3 (his3) actin (act), beta-tubulin (ß-tubulin) and glutamine synthetase (gs)], six Colletotrichum species were identified, including two new species, namely Colletotrichumguangdongense and C.tomentosae. Colletotrichumasianum, C.plurivorum, C.siamense and C.tainanense are identified as being the first reports on C.grandis cv. "Tomentosa" worldwide. This study is the first comprehensive study on endophytic Colletotrichum species on C.grandis cv. "Tomentosa" in China.

Red ginseng polysaccharide exhibits anticancer activity through GPX4 downregulation-induced ferroptosis.

CONTEXT: Red ginseng polysaccharide (RGP) is an active component of the widely used medicinal plant Panax ginseng C. A. Meyer (Araliaceae), which has displayed promising activities against cancer cells. However, the detailed molecular mechanism of RGP in ferroptosis is still unknown. OBJECTIVE: This study evaluates the effects of RGP in cancer cells. MATERIALS AND METHODS: A549 and MDA-MB-231 cells were used. Cell proliferation was measured by CCK-8 assay after being treated with RGP at concentrations of 0, 50, 100, 200, 400, 800 and 1600 µg/mL at 0, 12, 24 and 48 h. Lipid reactive oxygen species (ROS) levels were assessed by C11-BODIPY assay. The control group was treated with PBS. RESULTS: RGP inhibited human A549 (IC50: 376.2 µg/mL) or MDA-MB-231(IC50: 311.3 µg/mL) proliferation and induced lactate dehydrogenase (LDH) release, promoted ferroptosis and suppressed the expression of GPX4. Moreover, the effects of RGP were enhanced by the ferroptosis inducer erastin, while abolished by ferroptosis inhibitor ferrostatin-1. DISCUSSION AND CONCLUSIONS: Our study is the first to demonstrate (1) the anticancer activity of RGP in human lung cancer and breast cancer. (2) RGP presented the anti-ferroptosis effects in lung and breast cancer cells via targeting GPX4.

Stagonosporopsis pogostemonis: A Novel Ascomycete Fungus Causing Leaf Spot and Stem Blight on Pogostemon cablin (Lamiaceae) in South China.

Pogostemon cablin is one of the well-known Southern Chinese medicinal plants with detoxification, anti-bacterial, anti-inflammatory, and other pharmacological functions. Identification and characterization of phytopathogens on P. cablin are of great significance for the prevention and control of diseases. From spring to summer of 2019 and 2020, a leaf spot disease on Pogostemon cablin was observed in Guangdong Province, South China. The pathogen was isolated and identified based on both morphological and DNA molecular approaches. The molecular identification was conducted using multi-gene sequence analysis of large subunit (LSU), the nuclear ribosomal internal transcribed spacer (ITS), beta-tubulin (ß-tubulin), and RNA polymerase II (rpb2) genes. The causal organism was identified as Stagonosporopsis pogostemonis, a novel fungal species. Pathogenicity of Stagonosporopsis pogostemonis on P. cablin was fulfilled via confining the Koch's postulates, causing leaf spots and stem blight disease. This is the first report of leaf spot diseases on P. cablin caused by Stagonosporopsis species worldwide.

Postsynaptic GluR2 Involved in Amelioration of Aß-Induced Memory Dysfunction by KAIXIN-San Through Rescuing Hippocampal LTP in Mice.

Kaixin-San (KXS), a Chinese formula, was used to treat "amnesia," a senile dementia in the modern world. This formula was reported to improve behavioral performances in many animal models. This study was designed to explore how KXS has improved amyloid-ß (Aß)-induced memory dysfunction in mice. The mouse models were achieved through unilateral ventricle injection with Aß42. The effects of KXS on memory improvement were evaluated by the step-down test. The electrophysiological changes induced by KXS were measured by long-term potentiation (LTP) analysis in the hippocampus in vivo. The expression of glutamate receptor 2 (GluR2) was observed through immunohistochemical staining. Behavioral experiment outcome demonstrated reduced avoidance time and increased error time during the step-down test in the mice of Aß group. This memory impairment, however, was reversed by KXS. Electrophysiological experiment showed no significant difference between Aß group and KXS group either in the size or the shape of field excitatory postsynaptic potentiation recorded from perforant path to dentate gyrus pathway. However, LTP in this region was reduced by Aß and recovered by KXS administration. Moreover, immunohistochemical staining showed increased postsynaptic GluR2 expression in DG area in KXS group. These findings suggest that Aß results in impairment to memory function of the animals, and KXS protects the animal from memory loss by rescuing LTP through postsynaptic mechanism which refers to increasing GluR2 expression.

A novel signal processing approach to auditory phantom perception.

The ear and brain interact in an orchestrated manner to create sensations of phantom tones that are audible to listeners despite lacking physical presence in original sounds. The relative contribution of peripheral sensory cell activity and cortical mechanisms to phantom hearing remains elusive. The current study addressed the question of whether non-linear components of a complex signal exist that are not captured by the linear combination of cosines in a series. To this end, we investigated the source and spectro-temporal dynamics of non-linear components within two-tone complexes related to phantom acoustic perception. The empirical mode decomposition, a method for non-linear and non-stationary processes, was applied to extract the extra-aural existence of an oscillatory component within the original signal associated with the phantom sound. This travelling wave (phantom) has never before been observed in the sound's linear spectrum. We showed that the wave travels at a velocity that accurately maps onto the perceived phantom tone frequency. Phase coherence of oscillatory mode dynamics predicted discrimination sensitivity to phantom sounds by listeners. Perceived incidences of phantom tones correlated with magnitude of the Hilbert power spectra of the extra-aural component. Findings suggest a possible origin of phantom sounds that exists within the original signal, with potential implications for current models of non-linear cochlear mechanics and cortical dynamics in generating phantom percepts.

Spectrotemporal window of binaural integration in auditory object formation.

Binaural integration of interaural temporal information is essential for sound source localization and segregation. Current models of binaural interaction have shown that accurate sound localization in the horizontal plane depends on the resolution of phase ambiguous information by across-frequency integration. However, as such models are mostly static, it is not clear how proximate in time binaural events in different frequency channels should occur to form an auditory object with a unique lateral position. The present study examined the spectrotemporal window required for effective integration of binaural cues across frequency to form the perception of a stationary position. In Experiment 1, listeners judged whether dichotic frequency-modulated (FM) sweeps with a constant large nominal interaural delay (1500 µs), whose perceived laterality was ambiguous depending on the sweep rate (1500, 3000, 6000, and 12,000 Hz/s), produced a percept of continuous motion or a stationary image. Motion detection performance, indexed by d-prime (d') values, showed a clear effect of sweep rate, with auditory motion effects most pronounced for low sweep rates, and a punctate stationary image at high rates. Experiment 2 examined the effect of modulation rate (0.5, 3, 20, and 50 Hz) on lateralizing sinusoidally frequency-modulated (SFM) tones to confirm the effect of sweep rate on motion detection, independent of signal duration. Lateralization accuracy increased with increasing modulation rate up to 20 Hz and saturated at 50 Hz, with poorest performance occurring below 3 Hz depending on modulator phase. Using the transition point where percepts changed from motion to stationary images, we estimated a spectrotemporal integration window of approximately 150 ms per octave required for effective integration of interaural temporal cues across frequency channels. A Monte Carlo simulation based on a cross-correlation model of binaural interaction predicted 90% of the variance on perceptual motion detection performance as a function of FM sweep rate. Findings suggest that the rate of frequency channel convergence of binaural cues is essential to binaural lateralization.

Binaural localization of musical pitch using interaural time differences in congenital amusia.

Naturally occurring sounds are routinely periodic. The ability to phase-lock to such periodicity facilitates pitch perception and interaural time differences (ITDs) determination in binaural localization. We examined whether deficient pitch processing in individuals with congenital amusia (tone deafness) is accompanied by impaired ability to lateralize musical pitch at auditory periphery and memorize the location of pitch at the working memory level. If common mechanisms subserve processing of temporal-fine-structure based pitch and ITDs, then deficient processing of one feature should impair performance on the other. Thus, we measured ITD discrimination thresholds using an adaptive-tracking procedure for lateralizing musical tone pairs separated by different semitone intervals. Amusic individuals exhibited normal ITD thresholds comparable to those of matched controls, which were not affected by concurrent pitch changes. For working memory tasks, the amusic group performed significantly worse than matched controls in probed pitch recall, irrespective of the complexity level of concurrent variations along the ITD dimension of the melodic sequence. Interestingly, despite normal peripheral ITD thresholds, amusic individuals performed worse than controls in recalling probed locations of tones within a sequence of musical notes originating from different ITD-simulated locations. Findings suggest that individuals with congenital amusia are unimpaired in temporal fine-structure encoding to determine the location of musical pitch based on binaural ITD information at the auditory periphery. However, working memory for a sequence of sounds' ITD-dependent spatial location is here shown to be impaired and dissociated from the pitch feature of sounds at the working memory level.

Iodide and iodate effects on the growth and fruit quality of strawberry.

BACKGROUND: Iodine deficiency is an environmental health problem affecting one-third of the global population. An iodine biofortification hydroponic experiment was conducted to explore the iodide and iodate uptake characteristics of strawberry plants, to measure the dosage effects of iodine on plant growth and to evaluate the influence of I- or IO3- application on fruit quality. RESULTS: After biofortification, the iodine contents of the fresh strawberry fruits were 600-4000 µg kg-1 , covering the WHO dietary iodine allowance of 150 µg · day-1 for adults. The iodine uptake of the strawberry plants increased with increasing I- or IO3- concentration of the culture solution. At the same iodine concentration, the iodate uptakes of various plant organs under I- treatments were apparently more than those under IO3- treatments. Low-level exogenous iodine (I- ≤ 0.25 mg L-1 or IO3- ≤ 0.50 mg L-1 ) not only promoted plant growth and increased biomass per plant, but also improved fruit quality by enhancing the vitamin C and soluble sugar contents of the strawberry fruits. Nevertheless, excessive exogenous iodine inhibited plant growth and reduced biomass per plant. IO3- uptake apparently increased the total acidity and nitrate content of the fruits, reducing the quality of the strawberry fruits. Conversely, I- uptake obviously decreased the total acidity and nitrate content of the strawberry fruits, improving the fruit quality. CONCLUSION: The strawberry can be used as a target crop for iodine biofortification. Furthermore, applying an appropriate dose of KI can improve the fruit quality of the strawberry plants. © 2016 Society of Chemical Industry.

[GC-MS analysis and cytotoxic activity of the supercritical extracts from roots and stems of Zanthoxylum nitidum].

The volatile components of roots and stems of Zanthoxylum nitidum were investigated by supercritical fluid carbon dioxide extraction (SFE-CO2) and gas chromatography-mass spectrometry(GC-MS). Thirty-one and fifty-one compounds were identified in the supercritical extracts from roots and stems of Z. nitidum, respectively, and total twenty-seven compounds were the common constituents. Among them, the major constituents in root and stem supercritical extracts were spathulenol (18.49 and 26.18%), n-hexadecanoic acid (14.24% and 12.79%), ar-tumerone (6.95% and 8.88%), oleic acid (8.39% and 5.71%) and hexanoic acid (4.39% and 7.78%). The in-vitro MTT assay showed that the volatile components of roots and stems of Z. nitidum did not exhibited any cytotoxic activity against human cancer Huh-7 and normal IEC-6 cells. These results indicated the same nature of the volatile constituents in the root and stem of Z. nitidum. This investigation may provide further evidence for expansion of medicinal parts of Z. nitidum.

[Research on the distribution difference of MRI signals in osteonecrosis of the femoral head patients of different TCM syndrome types].

OBJECTIVE: To observe the distribution difference of magnetic resonance imaging (MRI) signals in osteonecrosis of the femoral head (ONFH) patients of different TCM syndrome types. METHODS: Recruited 29 ONFH patients were assigned to the tendon and vessel stagnation group (14 cases) and the Gan-Shen deficiency group (15 cases) according to TCM syndrome typing. The distribution difference of their MRI signals of MRIT1WI, T2WI + fs, T1 and T2 combined signal were compared. RESULTS: There was statistical difference in T1W1 signal distribution between the two TCM syndrome types (P = 0.04). There was no statistical difference in T2WI + fs or T1 and T2 combined signal between the two TCM syndrome types (P = 0.42, P = 0.15). MRI signals in the tendon and vessel stagnation group were mainly manifested as fat-like signals,while they were mainly manifested as mixed signals in the Gan-Shen deficiency group. CONCLUSION: Distribution difference of MRI signals exists between ONFH patients of different TCM syndrome types.

[Active neuraminidase constituents of Polygonum cuspidatum against influenza A(H1N1) influenza virus].

OBJECTIVE: To isolate and identify active neuraminidase constituents of Polygonum cuspidatum against influenza A (H1N1) influenza virus. METHOD: On the basis of the bioassay-guided fractionation,such chromatographic methods as silica gel, sephadex LH-20 and HPLC were adopted to isolate active constituents of extracts from Polygonum cuspidatum, and their molecular structures were identifiied on the basis of their spectral data such as NMR and MS and physico-chemical properties. RESULT: Seven compounds were isolated from the ethyl acetate extract of P. cuspidatum and identified as 2-methoxystypandrone (1), emodin (2), resveratrol (3), polydatin (4), emodin-8-O-beta-D-glucopyranoside (5), (E)-3, 5, 12-trihydroxystilbene-3-O-beta-D-glucopyranoside-2'-(3", 4", 5"-trihydroxybenzoate) (6) and catechin-3-O-gallate (7), respectively. Among them, the NA test showed that compounds 3, 6 and 7 had inhibitory effect against NAs activity, with IC50 values of 129.8, 44.8 and 21.3 micromol x L(-1), respectively. Moreover, the further CPE test showed compounds 6 and 7 had significant inhibitory effect against H1N influenza virus (EC50 = 5.9, 0.9 micromol x L(-1), respectively), with very low cytotoxicity to the host cells, their therapeutic selective index(SI) in MDCK cells ranged from 56 to 269. CONCLUSION: The neuraminidase inhibitors against H1N1 anti-influenza virus isolated from extracts of P. cuspidatum on the basis of the bioassay-guided fractionation are significant in specifying their therapeutic material basis and drug R&D against influenza.

A study on the correlativity of MRI signal classifications with TCM syndromes in femoral head necrosis patients.

OBJECTIVE: To probe into the relation between magnetic resonance imaging (MRI) signal classifications and TCM syndromes in femoral head necrosis patients, so as to provide reference for TCM diagnosis of this disease. METHODS: Refering to the criteria for TCM syndrome types of necrosis of the femoral head described in "The Guiding Principles of Clinical Studies of New Chinese Drugs" and Shimizu and Mitchell's MRI signal classifications, MRI signal classifications between different TCM syndrome types were compared. RESULTS: The Shimizu signal classification of different TCM syndrome types had statistically significant difference (P = 0.04); Both T2WI+fs and Mitchell signal classifications of different TCM syndrome types had no statistical by significant differences (P = 0.42 or P = 0.15). CONCLUSION: There is a certain correlativity of TCM syndrome types of necrosis of the femoral head with T1WI signal classification of MRI. MRI signal classification may contribute to objectivity in TCM syndrome typing of this disease.

Induction of neuronal differentiation in neurosphere stem cells by ellagic acid derivatives.

A bioassay-guided fractionation of methanol extracts of stem barks, combined with screening based on Epidermal Growth Factor (EGF)-responsive neural stem cells (erNSCs) differentiation assay, has been used. This study resulted in the isolation of 3,3'-di-O-methylellagic acid 1, 3,3'-di-O-methyl ellagic acid-4-O-beta-D-xylopyranoside 2, ellagic acid 3, and arjunolic acid 4. Among them, compounds 1 and 2 exhibit potent induction of neuronal differentiation in neurosphere stem cells with no cytotoxic effect. These results indicate that compounds 1 and 2 may be useful as pharmacological agents for the treatment of neurodegenerative diseases. These compounds may account, for the use of T. superba in folk medicine for nervous system and mental disorders.

Panaxadiol glycosides that induce neuronal differentiation in neurosphere stem cells.

Bioassay-guided fractionation, combined with screening based on EGF-responsive neural stem cells (NSCs) differentiation assay, has been used to search for active molecules from Panax notoginseng. Ginsenosides Rg3 (1), Rk1 (2), and Rg5 (3) were identified as potential neurogenic molecules. The degrees of their neurogenic effects were found to be 3 > 2 > 1. The neurogenic effect of 3 represents a biphasic dose- and time-dependent regulation. Transient exposure of NSCs to 8 microM 3 for 24 h followed by 1 microM and 72 h incubation was the optimal procedure for the induction of neurons in NSCs, and compound 3 resulted in an approximately 3-fold increase in neurogenesis at the expense of astrogliogenesis. The neurogenic effect of 3 was completely eliminated by the Ca2+ channel antagonist nifedipine. These findings imply that 3 may be utilized as a pharmacological agent in studying the molecular regulation of neurogenesis of brain stem cells and, subsequently, for treatment of neurodegenerative diseases.