Paradoxical herniation associated with hyperbaric oxygen therapy after decompressive craniectomy: A case report

BACKGROUND

Whether hyperbaric oxygen therapy (HBOT) can cause paradoxical herniation is still unclear.

CASE SUMMARY

A 65-year-old patient who was comatose due to brain trauma underwent decompressive craniotomy and gradually regained consciousness after surgery. HBOT was administered 22 d after surgery due to speech impairment. Paradoxical herniation appeared on the second day after treatment, and the patient's condition worsened after receiving mannitol treatment at the rehabilitation hospital. After timely skull repair, the paradoxical herniation was resolved, and the patient regained consciousness and had a good recovery as observed at the follow-up visit.

CONCLUSION

Paradoxical herniation is rare and may be caused by HBOT. However, the underlying mechanism is unknown, and the understanding of this phenomenon is insufficient. The use of mannitol may worsen this condition. Timely skull repair can treat paradoxical herniation and prevent serious complications.

Telmisartan Alleviates Alzheimer's Disease-Related Neuropathologies and Cognitive Impairments

BACKGROUND

Alzheimer's disease (AD) is the most common type of neurodegenerative disorder. There are few effective medications for halting the progression of AD. Telmisartan (TEL) is a widely used anti-hypertensive drug approved by FDA. Aside from treating hypertension, TEL has been revealed to provide protection against AD. However, the underlying mechanisms remain unclear.

OBJECTIVE

To investigate the mechanisms underlying the beneficial effects of TEL against AD.

METHODS

Eight-month-old APP/PS1 mice were administered with 5 mg/kg TEL once per day for 4 successive months. Nesting test, Y-maze test, and Morris water maze test were employed to assess the cognitive and executive functions. Neuronal and synaptic markers, Aβ pathology, neuroinflammation, and oxidative stress in the brains were measured. Specifically, components involved in amyloid-β (Aβ) production and degradation pathway were analyzed to explore the mechanisms underlying the therapeutic effect of TEL against Aβ pathology. The primary microglia were used to uncover the mechanisms underlying the anti-inflammatory effects of TEL in AD. Additionally, the preventive effect of TEL against AD were investigated using 4-month-old APP/PS1 mice.

RESULTS

TEL treatment ameliorated cognitive and executive impairments, neuronal and synaptic injury, Aβ pathology, neuroinflammation, and oxidative stress in APP/PS1 mice. The favorable effects of TEL on Aβ pathology were achieved by inhibiting enzymatic Aβ production and facilitating enzymatic and autophagic Aβ degradation. Meanwhile, the anti-inflammatory effects of TEL were accomplished via microglial PPARγ/NLRP3 pathway. The administration of TEL prior to symptom onset prevented AD-related cognitive decline and neuropathologies.

CONCLUSION

TEL represents a promising agent for AD prevention and treatment.

A spatiotemporal barrier formed by Follistatin is required for left-right patterning

How left-right (LR) asymmetry emerges in a patterning field along the anterior-posterior axis remains an unresolved problem in developmental biology. Left-biased Nodal emanating from the LR organizer propagates from posterior to anterior (PA) and establishes the LR pattern of the whole embryo. However, little is known about the regulatory mechanism of the PA spread of Nodal and its asymmetric activation in the forebrain. Here, we identify bilaterally expressed Follistatin (Fst) as a regulator blocking the propagation of the zebrafish Nodal ortholog Southpaw (Spaw) in the right lateral plate mesoderm (LPM), and restricting Spaw transmission in the left LPM to facilitate the establishment of a robust LR asymmetric Nodal patterning. In addition, Fst inhibits the Activin-Nodal signaling pathway in the forebrain thus preventing Nodal activation prior to the arrival, at a later time, of Spaw emanating from the left LPM. This contributes to the orderly propagation of asymmetric Nodal activation along the PA axis. The LR regulation function of Fst is further confirmed in chick and frog embryos. Overall, our results suggest that a robust LR patterning emerges by counteracting a Fst barrier formed along the PA axis.

Nodal coordinates the anterior-posterior patterning of germ layers and induces head formation in zebrafish explants

Much progress has been made toward generating analogs of early embryos, such as gastruloids and embryoids, in vitro. However, methods for how to fully mimic the cell movements of gastrulation and coordinate germ-layer patterning to induce head formation are still lacking. Here, we show that a regional Nodal gradient applied to zebrafish animal pole explant can generate a structure that recapitulates the key cell movements of gastrulation. Using single-cell transcriptome and in situ hybridization analysis, we assess the dynamics of the cell fates and patterning of this structure. The mesendoderm differentiates into the anterior endoderm, prechordal plate, notochord, and tailbud-like cells along an anterior-posterior axis, and an anterior-posterior-patterned head-like structure (HLS) progressively forms during late gastrulation. Among 105 immediate Nodal targets, 14 genes contain axis-induction ability, and 5 of them induce a complete or partial head structure when overexpressed in the ventral side of zebrafish embryos.

The TREM2 H157Y Variant Influences Microglial Phagocytosis, Polarization, and Inflammatory Cytokine Release

Previously, we reported that H157Y, a rare coding variant on exon 3 of the triggering receptor expressed on myeloid cells 2 gene (TREM2), was associated with Alzheimer's disease (AD) risk in a Han Chinese population. To date, how this variant increases AD risk has remained unclear. In this study, using CRISPR-Cas9-engineered BV2 microglia, we tried to investigate the influence of the Trem2 H157Y variant on AD-related microglial functions. For the first time, we revealed that the Trem2 H157Y variant inhibits microglial phagocytosis of amyloid-β, promotes M1-type polarization of microglia, and facilitates microglial release of inflammatory cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. These findings provide new insights into the cellular mechanisms by which the TREM2 H157Y variant elevates the risk of AD.

Lamotrigine protects against cognitive deficits, synapse and nerve cell damage, and hallmark neuropathologies in a mouse model of Alzheimer’s disease

Lamotrigine (LTG) is a widely used drug for the treatment of epilepsy. Emerging clinical evidence suggests that LTG may improve cognitive function in patients with Alzheimer’s disease. However, the underlying molecular mechanisms remain unclear. In this study, amyloid precursor protein/presenilin 1 (APP/PS1) double transgenic mice were used as a model of Alzheimer’s disease. Five-month-old APP/PS1 mice were intragastrically administered 30 mg/kg LTG or vehicle once per day for 3 successive months. The cognitive functions of animals were assessed using Morris water maze. Hyperphosphorylated tau and markers of synapse and glial cells were detected by western blot assay. The cell damage in the brain was investigated using hematoxylin and eosin staining. The levels of amyloid-β and the concentrations of interleukin-1β, interleukin-6 and tumor necrosis factor-α in the brain were measured using enzyme-linked immunosorbent assay. Differentially expressed genes in the brain after LTG treatment were analyzed by high-throughput RNA sequencing and real-time polymerase chain reaction. We found that LTG substantially improved spatial cognitive deficits of APP/PS1 mice; alleviated damage to synapses and nerve cells in the brain; and reduced amyloid-β levels, tau protein hyperphosphorylation, and inflammatory responses. High-throughput RNA sequencing revealed that the beneficial effects of LTG on Alzheimer’s disease-related neuropathologies may have been mediated by the regulation of Ptgds, Cd74, Map3k1, Fosb, and Spp1 expression in the brain. These findings revealed potential molecular mechanisms by which LTG treatment improved Alzheimer’s disease. Furthermore, these data indicate that LTG may be a promising therapeutic drug for Alzheimer’s disease.

The Alzheimer’s disease-associated gene TREML2 modulates inflammation by regulating microglia polarization and NLRP3 inflammasome activation

Triggering receptor expressed on myeloid cells-like 2 (TREML2) is a newly identified susceptibility gene for Alzheimer’s disease (AD). It encodes a microglial inflammation-associated receptor. To date, the potential role of microglial TREML2 in neuroinflammation in the context of AD remains unclear. In this study, APP/PS1 mice were used to investigate the dynamic changes of TREML2 levels in brain during AD progression. In addition, lipopolysaccharide (LPS) stimulation of primary microglia as well as a lentivirus-mediated TREML2 overexpression and knockdown were employed to explore the role of TREML2 in neuroinflammation in the context of AD. Our results show that TREML2 levels gradually increased in the brains of APP/PS1 mice during disease progression. LPS stimulation of primary microglia led to the release of inflammatory cytokines including interleukin-1β, interleukin-6, and tumor necrosis factor-α in the culture medium. The LPS-induced microglial release of inflammatory cytokines was enhanced by TREML2 overexpression and was attenuated by TREML2 knockdown. LPS increased the levels of microglial M1-type polarization marker inducible nitric oxide synthase. This effect was enhanced by TREML2 overexpression and ameliorated by TREML2 knockdown. Furthermore, the levels of microglial M2-type polarization markers CD206 and ARG1 in the primary microglia were reduced by TREML2 overexpression and elevated by TREML2 knockdown. LPS stimulation increased the levels of NLRP3 in primary microglia. The LPS-induced increase in NLRP3 was further elevated by TREML2 overexpression and alleviated by TREML2 knockdown. In summary, this study provides the first evidence that TREML2 modulates inflammation by regulating microglial polarization and NLRP3 inflammasome activation. These findings reveal the mechanisms by which TREML2 regulates microglial inflammation and suggest that TREML2 inhibition may represent a novel therapeutic strategy for AD.

Dysregulation of Circulatory Levels of lncRNAs in Parkinson's Disease

Emerging evidence suggested that long non-coding RNAs (lncRNAs) were involved in Parkinson's disease (PD) pathogenesis. Herein, we used gene expression profiles from GEO database to construct a PD-specific ceRNA network. Functional enrichment analysis suggested that ceRNA network might participate in the development of PD. PPI networks were constructed, and the ceRNA subnetwork based on five hub genes was set up. In a cohort of 32 PD patients and 31 healthy controls, the expression of 10 DElncRNAs (TTC3-AS1, LINC01259, ZMYND10-AS1, CHRM3-AS1, MYO16-AS1, AGBL5-IT1, HOTAIRM1, RABGAP1L-IT1, HLCS-IT1, and LINC00393) were further verified. Consistent with the microarray data, LINC01259 expression was significantly lower in PD patients compared with controls (P = 0.008). Intriguingly, such a difference was only observed among male patients and male controls when dividing study participants based on their gender (P = 0.016). However, the expression of other lncRNAs did not differ significantly between the two groups. Receiver operating characteristic (ROC) curve analysis revealed that the diagnostic power of LINC01259 was 0.694 for PD and 0.677 for early-stage PD. GSEA enrichment analysis revealed that LINC01259 was mainly enriched in biological processes associated with immune function and inflammatory response. Moreover, LINC01259 expression was not correlated with age of patients, disease duration, disease stage, MDS-UPDRS score, MDS-UPDRS III score, MMSE score, and MOCA score. The current study provides further evidence for the dysregulation of lncRNAs in circulating leukocytes of PD patients, revealing that LINC01259 has clinical potential as a novel immune and inflammatory biomarker for PD and early-stage PD diagnosis.

[Research progress of the application of methacrylic anhydride gelatin hydrogel in wound repair]

Wound repair is a common clinical problem, which seriously affects the quality of life of patients and also brings a heavy burden to the society. Hydrogel-based multifunctional dressing has shown strong potential in the treatment of acute and chronic wounds. In addition to its good histocompatibility, cell adhesion, and biodegradability, methacrylic anhydride gelatin (GelMA) hydrogel has also attracted much attention due to its low cost, mild reaction conditions, adjustable physicochemical properties, and wide clinical applications. In this paper, the characteristics of GelMA hydrogel and its research progress in wound repair are introduced, and the future development of multifunctional GelMA hydrogel dressing for wound treatment is prospected.

Mycn regulates intestinal development through ribosomal biogenesis in a zebrafish model of Feingold syndrome 1

Feingold syndrome type 1, caused by loss-of-function of MYCN, is characterized by varied phenotypes including esophageal and duodenal atresia. However, no adequate model exists for studying the syndrome's pathological or molecular mechanisms, nor is there a treatment strategy. Here, we developed a zebrafish Feingold syndrome type 1 model with nonfunctional mycn, which had severe intestinal atresia. Single-cell RNA-seq identified a subcluster of intestinal cells that were highly sensitive to Mycn, and impaired cell proliferation decreased the overall number of intestinal cells in the mycn mutant fish. Bulk RNA-seq and metabolomic analysis showed that expression of ribosomal genes was down-regulated and that amino acid metabolism was abnormal. Northern blot and ribosomal profiling analysis showed abnormal rRNA processing and decreases in free 40S, 60S, and 80S ribosome particles, which led to impaired translation in the mutant. Besides, both Ribo-seq and western blot analysis showed that mTOR pathway was impaired in mycn mutant, and blocking mTOR pathway by rapamycin treatment can mimic the intestinal defect, and both L-leucine and Rheb, which can elevate translation via activating TOR pathway, could rescue the intestinal phenotype of mycn mutant. In summary, by this zebrafish Feingold syndrome type 1 model, we found that disturbance of ribosomal biogenesis and blockage of protein synthesis during development are primary causes of the intestinal defect in Feingold syndrome type 1. Importantly, our work suggests that leucine supplementation may be a feasible and easy treatment option for this disease.

Angiotensin-(1-7) Analogue AVE0991 Modulates Astrocyte-Mediated Neuroinflammation via lncRNA SNHG14/miR-223-3p/NLRP3 Pathway and Offers Neuroprotection in a Transgenic Mouse Model of Alzheimer's Disease

Objective

Emerging evidence suggests that brain angiotensin-(1–7) (Ang-(1–7)) deficiency contributes to the pathogenesis of Alzheimer’s disease (AD). Meanwhile, our previous studies revealed that restoration of brain Ang-(1–7) levels provided neuroprotection by inhibition of inflammatory responses during AD progress. However, the potential molecular mechanisms by which Ang-(1–7) modulates neuroinflammation remain unclear.

Materials and Methods

APP/PS1 mice were injected intraperitoneally with AVE0991 (a nonpeptide analogue of Ang-(1–7)) once a day for 30 consecutive days. Cognitive functions, neuronal and synaptic integrity, and inflammation-related markers were assessed. Since astrocytes played a crucial role in AD-related neuroinflammation whilst long noncoding RNAs (lncRNAs) were reported to participate in modulating inflammatory responses, astrocytes of APP/PS1 mice were isolated for high-throughput lncRNA sequencing to identify the most differentially expressed lncRNA following AVE0991 treatment. Afterward, the downstream pathways of this lncRNA in the anti-inflammatory action of AVE0991 were investigated using primary astrocytes.

Results

AVE0991 rescued spatial cognitive impairments and alleviated neuronal and synaptic damage in APP/PS1 mice. The levels of Aβ_1-42 in the brain of APP/PS1 mice were not affected by AVE0991. By employing high-throughput lncRNA sequencing, our in vitro study demonstrated for the first time that AVE0991 suppressed astrocytic NLRP3 inflammasome-mediated neuroinflammation via a lncRNA SNHG14-dependent manner. SNHG14 acted as a sponge of miR-223-3p while NLRP3 represented a direct target of miR-223-3p in astrocytes. In addition, miR-223-3p participated in the AVE0991-induced suppression of astrocytic NLRP3 inflammasome.

Conclusion

Our results suggest that Ang-(1–7) analogue AVE0991 inhibits astrocyte-mediated neuroinflammation via SNHG14/miR-223-3p/NLRP3 pathway and offers neuroprotection in APP/PS1 mice. These findings reveal the underlying mechanisms by which Ang-(1–7) inhibits neuroinflammation under AD condition and uncover the potential of its nonpeptide analogue AVE0991 in AD treatment.

[Evaluation of adhesive bone conduction hearing aid in pediatric patients with unilateral congenital aural atresia]

Objective: To evaluate the auditory efficacy and subjective satisfaction of adhesive bone conduction hearing aid in children with unilateral congenital aural atresia (UCAA). Methods: Ten subjects (5 males and 5 females) diagnosed with UCAA with an average age of 8.3 years old (ranged from 5 to 15) were included in Beijing Tongren Hospital, Capital Medical University from January to August 2019. The free sound field hearing threshold, word recognition score in quiet, speech reception threshold in noise and sound localization ability (results were measured by RMS error) tests were performed in unaided and aided situation, respectively. Subjective satisfaction questionnaires were also distributed to subjects. Paired t test and Wilcoxon signed rank test were used as statistical analysis methods. Results: The average hearing threshold in aided condition was improved by (21.9±4.4) dB (t=15.8，P<0.05). Speech recognition abilities were generally improved both under quiet and noise (P<0.05);however, when the binaural summation, squelch and head shadow effects were analyzed respectively, the binaural squelch effect was not statistically improved (P>0.05), while the other effects were improved in aided condition (P<0.05). In sound localization test, there was no significant difference of the RMS error value between the unaided and aided situation (P>0.05). The subjects got high satisfaction rates in three subjective questionnaires. Conclusion: The adhesive bone conduction hearing aid can provide significant audiological benefit for children with UCAA as well as raising the quality of their life.

[Application of multiple exposure assessment methods in occupational health risk assessment of trichloroethylene in electroplating enterprises]

Objective: To explore the applicability of different exposure assessment methods in occupational health risk assessment of trichloroethylene (TCE) occupation posts in electroplating enterprise. Methods: In November 2018, the occupational health risk assessments are conducted in trichloroethylene (TCE) occupation posts of 6 metal plating enterprises in a street in Shenzhen by using the qualitative risk assessment, semi-quantitative risk assessment (including contact ratio method, contact index method and synthesis index method) and quantitative risk assessment method (including non-carcinogenic and carcinogenic risk assessment methods) , and the results of different methods are compared. Results: The results of qualitative assessment method are all level 4 (high risk) ; the results of contact ratio method show that the risk level is level 5 (very high risk) ; the results of contact index method and Synthesis index method show that the risk level is level 3 and level 4, 66.7% and 33.3% respectively; Non-carcinogenic risk assessment results show that TCE jobs are "unacceptable"; carcinogenic risk assessment results in carcinogenic inhalation excess risk of 50% each being "unacceptable" and "acceptable". The results of the six risk assessment methods showed that there were 3 "substantially consistent", 1 "partially consistent", and 2 "inconsistent" among the 6 companies. Conclusion: Synthesis index method and the carcinogenic risk assessment method are more suitable for occupational health risks of TCE occupation posts.

[Establishment of the characterization of an adult digits-in-noise test based on internet]

Objective:The aim of this study is to explore the sensitivity and specificity of the internet-based digital noise threshold (DIN) test for detecting noise-induced hearing loss, expecting to provide a rapid and effective screening tool for clinical application. Method:This study enrolled 50 adult subjects, of which 34 were normal hearing (NH), 16 patients with sensorineural hearing loss (SNHL). Pure-tone audiometry, acoustic immittance and DIN test were tested respectively. Pearson's correlation coefficient was used to analyze the correlation between NH and SNHL. The eigenvalues, sensitivities and specificities of the tested materials were determined by receiver operating characteristic curve (ROC curve) and the area under the curve. Result:①The correlation between the speech recognition threshold (SRTn) and pure tone audiometry thresholds (average of 0.5, 1, 2 and 4 kHz) was 0.85 (P<0.01). ②The optimal cut off point for DIN-based test materials under noise based on Internet technology was -9.5 dB, which means that hearing loss is highly suspect when DIN is above this value under noise and should be referred to a hearing center for diagnostic tests. ③The sensitivity and specificity was 0.938 and 0.941 respectively with -0.95 dB as the best cutoff point. Conclusion:This DIN test based on Internet, which has an excellent performance as a hearing screening method with good sensitivity and specificity, could be an effective tool for large-scale adult hearing screening.

Copper Nanoparticles Show Obvious in vitro and in vivo Reproductive Toxicity via ERK Mediated Signaling Pathway in Female Mice

Copper nanoparticles (Cu-NPs) and other inorganic nanomaterials have caused increasing concern owing to be widely used. Early studies have reported that they can result in injuries to the kidney, liver and spleen of mice; cause embryonic damage; and inhibit the reproductive capacity of red worms. However, few studies have reported the toxicity of Cu-NPs on the reproductive systems of mammals. In the present work, we explored the cytotoxicity of Cu-NPs in human extravillous trophoblast cells and in the reproductive organs of mice. Cu-NPs induced ovarian and placental pathophysiology and dysfunction in mice. These nanoparticles also induced apoptosis and suppressed the proliferation of human extravillous trophoblast cells and caused cell cycle arrest at the G2/M phase in a time-and dose-dependent manner. Cu-NPs can significantly damage the mitochondrial membrane potential (MMP), which suggests that Cu-NPs can activate the mitochondria-mediated apoptosis signaling pathway. We also observed that Cu-NPs significantly inhibit the expression of BRAF, ERK, and MITF expression, all of which are important genes in the ERK signaling pathway. Our research demonstrated that Cu-NPs exert obvious reproductive toxicity in mice by disrupting the balance of sex hormones and exert cytotoxicity on human extravillous trophoblast cells, and ERK signaling and the mitochondrial apoptosis pathway made great contribution to the toxicity of Cu-NPs on female mice.

[Study on the characters of wideband tympanometry in newborns with normal hearing]

Objective:The aim of this study is to establish the characteristic of wideband tympanometry (WBT) in neonates with normal hearing. Method:Ninety newborn babies (149 ears) who had received rooming in care and passed hearing screening were randomly selected to test WBT. The screening programme consisted of distortion product otoacoustic emissions (DPOAE) and tympanometry at 1 kHz. The eigenvalue of ear canal volume, middle ear resonance frequency and acoustic absorptivity were obtained initially to explore the influence of gender and mode of delivery on the eigenvalues. Result:①Ear canal volume: The ear canal volume varied within (0.50±0.12)ml. The statistically significant correlationwas observed between ear canal volume and gender as well as the way of delivery (P<0.01). ②Resonance frequency: the resonant frequency distributed from 128 Hz to 642 Hz (mean 328.2±125.76 Hz). No statistically significant correlation (P>0.05) was observed between resonance frequency and gender as well as the way of delivery. ③Frequency wideband absorbance function: the shape of the curve showed two peaks and two troughs. The three most values were located in 1 296 Hz, 2 000 Hz and 5 339 Hz. No statistically significant correlation (P>0.05) was observed between acoustic absorptivity and gender as well as way of delivery. Conclusion:Resonance frequency and frequency acoustic absorptivity functions of newborns are different from adults. It is necessary to establish the normal reference value of WBT for newborns in China in order to promote this technique in the clinic.

[Analysis of reliability and validity of the Chinese version of the Satisfaction with Amplification in Daily Life]

Objective:To investigate the reliability and validity of the Chinese version of the Satisfaction with Amplification in Daily Life (SADL).Method:Ninety adult hearing aid users were evaluated with Chinese version of the SADL.Result:①Reliability:Cronbach's α score of overall SADL score was 0.814 and the four subdomains were 0.543-0.824. ②Validity: The correlation coefficients between overall SADL score and the four subdomains were 0.514-0.826(all P<0.01).There were weak or no correlations among the four subdomains. The evaluation of content validity by expertreview showed the questionnaire had good content validity. SADL total scores in bilateral hearing aid userswere significantly higher than those in unilateral hearing aid users (t=2.192,P<0.05).Conclusion:The Chinese version of the SADL meets many psychometric criteria of a robust instrument. It possesses appropriate validity and good reliability, and can be used to measure the outcome for adult hearing aid users in China.

[The study of wideband acoustic immittance normative data of young people]

Objective:To explore the normative data of wideband acoustic absorption rate of young people with normal hearing, and the related factors of wideband acoustic immittance.Method:Eighty six cases of young people with normal hearing (43 cases of male, 43 cases of female) were collected in the clinical audiology centers of Beijing Tongren Hospital, Capital University of Medical. The average age is (22.0±1.5) years. Pure tone audiometry in the range of 250 to 8 000 Hz in each octave is carried out, and the air conduction thresholds are less than 25 dB HL; 226 Hz tympanometry were type A. For all subjects, the wideband acoustic immittance measurement was conducted at 226-8 000 Hz, and a total of 107 frequency points were carried out.Result:The test results of 172 ears were statistically analyzed.①In the range of 250-8 000 Hz,acoustic absorption rate in the low frequency range increases gradually, and the peak is found in the range of 1 000 to 3 000 Hz;getting along with the increase of frequency and acoustic absorption rate gradually decreases slowly.②The acoustic absorption rate in the range of 4 200-4 900 Hzin female subjects was significantly higher than that in male subjects.③There was no significant relationship between gender, compliance, peak pressure, and width in 226 Hz tympanometry (P=0.319, 0.831, 0.786), however there was a significant relationship between gender and the ear canal volume (P<0.01).④There was no significant relationship between gender and the resonance frequency (P>0.05).⑤There was a significant correlation between height/weight and ear canal volume (P<0.05), and there was a significant relationship between the ear canal volume and the resonance frequency (P<0.05).Conclusion:The acoustic absorption rate of young people in the low frequency range was lower, then increases gradually, and the peak was found in the range of mid-high frequency. The difference in the wideband absorption rate between genders was significant. The height and weight had influence on the results of wideband acoustic immittance.

[Characterization of cortical auditory evoked potential (P1-N1-P2) in normal hearing young adults]

Objective:To explore the normal value and characteristic of cortical auditory evoked potential (P1-N1-P2) in normal hearing young adults.Method:Thirty normal hearing young people were recruited for this study. Cortical auditory evoked potential (P1-N1-P2) was performed at three different speech stimuli (/m/, /t/, /g/) and three different sound intensity (55, 65, 75 dB SPL) using the Australia HEARLab test system. Analysis of Variance (ANOVA) was used to evaluate the influence of speech stimuli and sound intensity and gender to latency and amplitude of P1-N1-P2.Result:①The normal range of latency and amplitude of P1-N1-P2 for three different speech stimuli and stimuli intensity were established. ②There were significant differences among three different speech stimuli for latency (P< 0.05) and amplitude (P< 0.05) of N1 and the latency of wave P2 (P< 0.05). ③There were no significant differences among three different stimulus intensity for the amplitude and latency of P1-N1-P2 (P> 0.05). ④There were significant differences between gender for amplitude of the wave N1 and P2 and the latency of N1 (P> 0.05).Conclusion:We initially acquired the normal range of cortical auditory evoked potential (P1-N1-P2) with different speech stimuli and different stimulus intensities in normal hearing young adults. It is also found that P1-N1-P2 values evoked by different speech stimuli showed diffrenent characteristics and stimulus frequency had a significant influence on N1 and P2 wave characteristics. This study provides reference and experience for the further application of this technology in clinical practice.

[The audiological characteristics of large vestibular aqueduct syndrome in infants and young children]

Objective:To investigate the audiological characteristics of large vestibular aqueduct syndrome(LVAS) in infants and young children, and to provide suggestion for the early diagnosis and early intervention.Method:One hundred and twenty-four cases diagnosed as LVAS were enrolled in our study. Acoustic immittance, pediatric audiometry and(or) auditory steady state responses and auditory brainstem response test were tested to analyze the degree and configuration of hearing loss, and air-bone threshold difference and short latency negative response in auditory brainstem response.Result:The configuration of the hearing loss, includes 44.8%(111/248) of high frequency loss, 19.0%(47/248) of flat, 13.7%(34/248) of rising, 3.6%(9/248) of U type, and 19.0%(47/248) of the configuration which cannot be distinguished. The distribution of the degree of the hearing loss in total 124 cases (248 ears) includes 73.4%(182/248) of profound hearing loss, 16.9%(42/248) of severe hearing loss, 6.9%(17/248) of moderate hearing loss, and 2.8%(7/248)of mild hearing loss. The acoustically evoked short latency negative response in ABR accounted for 27.4%(68/248). The emergence of ABR air-bone threshold difference accounted for 24.6%(61/248), and the mean difference was(19.3±14.2) dB nHL.Conclusion:Infants and young children with large vestibular aqueduct syndrome mostly has the characteristics of high frequency hearing loss curve, acoustically evoked short latency negative response in ABR and ABR bone-air threshold difference, that will remind clinicians of LVAS.

[The characteristic of lexical tone perception in native-mandarin normal hearing people]

Objective:The aim of this study is to explore the characteristic of lexical tone perception in nativemandarin normal hearing speakers.Method:Three types of continuum(Tone1/Tone2, Tone1/Tone4 and Tone2/Tone3) were constructed and each of them includes a 15 stimuli. All speech stimuli in these three continua were resynthesized by applying the PitchSynchronous OverLap and Add(PSOLA) method implemented in Praat to the same mandarin syllable, /a/, with a high level tone produced by a female native mandarin speaker. Forty native listeners of mandarin were recruited for this study and identification task was used to acquire the tonal perceptual data. SPSS 19.0 software was used to get the fitting curves of lexical tone perception. Result: The tone perception curves in nativemandarin normal hearing speakers were inverted Sshape. All the three tone perception curves showed steep upward or downward trend and obvious boundary.Each of tone perception curves has a definite intersection, and the tone perception performance has mutated at the intersection.Conclusion:There is the typically categorical perception of lexical tone identification in nativemandarin normal hearing people.

[Characteristics of cervical vestibular evoked myogenic potential in different test positions]

Objective: To investigate the characteristics of cervical vestibular evoked myogenic potential (cVEMP) of normal youth with different test positions, to study the relationship between test positions and test parameters, and to explore the suitable test position for clinical practice. Methods: Fifty healthy young volunteers (25 males, 25 females, 100 ears) were enrolled in this study. Two test positions were used, including sitting with the head turned away from the test (SIT) and supine with the head held straight up (SUP). The derivation rate, latency and amplitude were analyzed. Results: The derivation rates of both SIT and SUP were 100%. The VEMP threshold in SIT was (93.5±4.3)dBnHL. The latency of P1 and N2 in SIT was longer than that in SUP, with significant different (P< 0.05), the amplitude of P1-N2 in SIT was less than that in SUP, with significant different (P< 0.05). Regarding to the latency of P1 and N2 in SIT, the left was longer that right, with (P=0.013) and (P=0.015) respectively. The latency in SUP between sides was not significant (P>0.05). The amplitude ratio and asymmetry in SIT were more obvious than in supine position (P=0.009 and 0.016). In SIT position the P1-N2 amplitude in males was larger than in females, with significant difference (P=0.031); In SUP position the P1-N2 amplitude in males was less than in females, with significant difference (P=0.043). Conclusion: The cVEMP can be affected by the different test positions, it is recommended to select a more suitable test position according to the condition of the subject and the purpose of the test.

Tailoring the transmission lineshape spectrum of zigzag graphene nanoribbon based heterojunctions via controlling their width and edge protrusions

We report a first-principles analysis of electron transport through narrow zigzag graphene nanoribbon (up to 2.2 nm) based wedge-shaped heterojunctions. We show that the width difference between the electrode and the scattering region and the edge protrusion of heterojunctions can be tuned to endow the system's transmission spectrum with distinctive features. In particular, transport through junctions with a one sided protrusion in the scattering region is always dominated by a Breit-Wigner-type resonance right at the Fermi level, regardless of the large or small width difference. On the other hand, a junction with protrusions on both sides of the scattering region shows insulating behaviour near the Fermi level for a large width difference but weak transmission channels are formed at the core of the scattering region for a small width difference. When the protrusion is absent in the junction, transmission functions display rather complex structures: double peaks situating nearly symmetrically away from the Fermi level and a strongly asymmetric profile in the vicinity of the Fermi level are observed for large and small width differences, respectively. These results may shed light on the design of real connecting components in nanocircuits.

A multicenter, randomized, controlled trial of interferon alfacon-1 compared with alpha-2a-interferon in Chinese patients with chronic hepatitis C virus infection

BACKGROUND

Alpha-interferons are the accepted therapy for patients infected with chronic hepatitis C virus (HCV) in China. However, consensus interferon (CIFN) for HCV treatment is effective in patients with chronic hepatitis C from Western countries.

METHODS

This randomized, controlled trial was conducted to determine the safety and efficacy of CIFN at two doses, and to compare it with alpha-2a-interferon (IFN-alpha-2a) in Chinese patients with chronic HCV. Interferon-naive patients with chronic HCV infection (n = 187) were randomly chosen to receive 15 microg CIFN or 9 microg or 3 MU IFN-alpha-2a subcutaneously, three times a week for 24 weeks, followed by a 24 week observation period. Efficacy was evaluated by the normalization of serum alanine aminotransferase (ALT) and the non-detectability disappearance of serum HCV-RNA by using reverse-transcription-polymerase chain reaction. The safety of CIFN was evaluated by recording the type and severity of adverse effects.

RESULTS

The combined ALT and HCV-RNA end-of-treatment and sustained responses were observed to be greater for treatment with 15 microg CIFN (59.0% and 55.7%, respectively) compared to IFN alpha-2a (36.1% and 39.3%, respectively; P = 0.01 for the end-of-treatment, P = 0.07 for the sustained response). The combined ALT and HCV-RNA end-of-treatment and sustained responses for treatment with 9 microg CIFN (both 49.2%) were higher than those for IFN-alpha-2a (not statistically significant). Data were analyzed by using a logistic-multiple-variate regression model, which indicated that the higher IFN dose (15 microg or 9 microg CIFN vs 3 MU IFN-alpha-2a; P < 0.01) appeared to be associated with a better sustained response. The type, frequency and severity of adverse effects were comparable across treatment groups.

CONCLUSIONS

Consensus interferon appears to be safe and effective at concentrations of 9 and 15 microg, but 15 microg CIFN may be more effective than 3 MU IFN-alpha-2a, without increased toxicity.

[Inhibitory effects of co-cinobufotalin oral liquor on hepatitis B in vitro]

Co-Cinobufotalin Oral Liquor (CCOL) was studied for its ability to inhibit hepatitis B virus DNA replication, HBsAg and HBeAg expression in a HBV-transfected cell line (2.2.15 cell). The result showed that ID50 (the drug concentration that inhibits HBsAg or HBeAg secretion by 50%) was 0.08 mg/ml and 0.07 mg/ml on HBsAg and HBeAg respectively. CD50 (the drug concentration that reduces cell growth by 50%) was 2.5 mg/ml. TI (therapeutic index) was 31.3 and 35.7 respectively. The present data suggest that CCOL could exert a potent antiviral activity against HBV in vitro. Southern blot showed that CCOL inhibited HBV-DNA repication in a dose-dependent manner.

[Detection of plus and minus strand hepatitis C virus RNA in peripheral blood mononuclear cells and spermatid]

Plus and minus strands of HCV RNA in plasma, peripheral blood mononuclear cells (PBMC), sperm and spermatid of 8 patients with chronic hepatitis C were tested by the method of PCR to find out whether HCV exists and duplicates in extrahepatic cells or not. Plus HCV RNA was detected in all the plasma samples, but no minus HCV RNA was detected. Plus strand HCV RNA was detected in 5 of 8 PBMC samples and minus strand in 2 of the 5 samples. Three of 5 male chronic hepatitis C patients were willing to cooperate and offer their sperm for detection. In the patients, no minus but plus strand HCV RNA was detected in both supernatant of sperm and spermatid. HCV RNA was not detected in the last washing solution for spermatid. The results suggest that: (1). Probably, only plus HCV RNA exists in plasma; (2). HCV exists and probably duplicates in PBMC; (3). HCV exists in sperm. The possibility of transmission of hepatitis C by sexual intercourse is really existent. But, HCV probably don't duplicate in spermatid.

[The diagnostic value of anti-HCV test in HCV infection]

Two hundred and ninety-six samples of patient serum and 28 samples of donor serum were tested for anti-HCV with second generation domestic made testing kit, and for HCV RNA with PCR assay. The aim of this study is to assess the diagnostic value of anti-HCV test in HCV infection and to discuss its value in screening of donors. The results were as follows HCV RNA was detected in 81.6% of the anti-HCV positive patient samples and in 21.7% of the anti-HCV negative patient samples. HCV RNA was not detected in 28 anti-HCV negative donors. These results reveals that positive anti-HCV is of high diagnostic value in HCV infection. Anti-HCV negative could not exclude HCV infection for samples suspected of HCV infection. However, screening donors with anti-HCV probably decreases HCV RNA positive rate considerably.

[Preliminary studies on inactivation of serum HCV]

Effects of heating and 60cobalt (60Co) irradiation to hepatitis C virus (HCV) RNA in sera were studied. HCV-RNA can not be detected by PCR in 10 positive serum samples after being heated at 56 degrees C for 10 hours. Whereas, HCV-RNA can still be detected in positive sera after being lyophilized and then heated at 60 degrees C for 20 hours. It suggested heating at 56 degrees C for 10 hours can inactivate HCV in sera and the sera should be in liquid status when thermal inactivation is taken. Lyophilized sera with thermal inactivation for HCV should be inactivated first and then lyophilized. But the safety of sera with heat-treatment should be further investigated. Inactivation of HCV in sera with 60Co irradiation needed extra large dose of it, and protein components in sera would obviously be altered. Therefore, inactivation of HCV in sera with 60Co irradiation is impractical.

[Therapeutic effect of combined treatment with Ara-A dauricine and Chinese herbs in chronic hepatitis B infection]

77 patients with chronic active or persistent hepatitis of type B proved by liver biopsy were divided into two groups. 39 cases were treated with Ara-A. dauricine and polysaccharide of pore umbellate as group I. 38 cases were treated with Ara-A, radix isatidis and radix salviae mitiorrhize as group II. By the end of 3 months in the course, the effective rates of ALT and AST were 68.6% and 68.4% in group I, 34.4% and 34.8% in group II. The rates of HBeAg from positive to negative were 35.9% and 39.5% in group I and II respectively. Follow up to 3 months after cessation of therapy, ALT level was normal in 55.6% of group I and 60% of group II: HBeAg was negative in 42.9% of group I and in 50% of group II. Follow up to 9 months after cessation of the treatment, ALT was normal in 56.3% of group I and in 62.5% of group II, HBeAg was negative in 37.5% of group I and in 60% of group II. These results show that dauricine and polysaccharide of pore umbellate did not strengthen the antiviral effect of Ara-A.

Insulinlike growth factor II expression and oval cell proliferation associated with hepatocarcinogenesis in woodchuck hepatitis virus carriers

Insulinlike growth factor II (IGF-II) is a highly mitogenic fetal growth factor suspected of regulating the growth of a wide spectrum of tissues via an autocrine or paracrine mode of action or both. High steady-state levels of IGF-II RNA were detected in 45% of hepatocellular carcinomas (HCCs) arising from woodchuck livers with persistent woodchuck hepatitis virus (WHV) infection. Analysis of WHV RNA in the same HCCs revealed that HCCs with high levels of IGF-II RNA contained low or undetectable levels of WHV RNA and HCCs with low levels of IGF-II RNA contained high levels of WHV RNA. Integrated WHV DNA was present in HCCs from both groups, but viral DNA replicating forms were present, predominantly in HCCs with low levels of IGF-II. Several IGF-II RNAs, the most prominent of which were poly(A) species of approximately 3.75 and 1.1 to 1.3 kilobases, were detected only in precancerous nodules and HCCs. Levels of IGF-II were elevated two- to three-fold in the serum of woodchucks with chronic active hepatitis preceding the occurrence of HCC. Proliferation of a population of oval cells, which arise from portal tract regions in the liver, preceded the development of HCC and was a prominent feature of livers from which tumors with high levels of IGF-II occurred. The HCCs tended to have distinct histological features according to their growth factor status. Tumors with low levels of IGF-II were generally highly differentiated acinar-trabecular HCCs, whereas tumors with high levels of IGF-II were more anaplastic, with regions of fibrosis and fatty accumulation. A model to relate the pathology of WHV infection to oval cell proliferation and IGF-II expression in the development of these heterogeneous HCCs is presented.