[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.

Vitamin intake and glaucoma risk: A systematic review and meta-analysis.

There is currently a lack of high-quality research on the best dietary recommendations for patients with early glaucoma or at high risk for glaucoma. This meta-analysis aims to clarify the relationship between vitamin intake and glaucoma risk. Electronic databases, including PubMed, EMbase, ScienceDirect, Cochrane Database, Clinicaltrials.gov, and Google Scholar, were searched for publications indexed as of September 18, 2021. Data were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). The I2 index was used to assess heterogeneity. We performed five meta-analyses of existing studies to summarize the evidence on the association between vitamin intake and glaucoma risk. The initial search identified 689 studies, eight of which (262,189 patients) met the eligibility criteria for the meta-analysis. The data showed that high-dose intake of vitamins A (OR=0.63, 95%CI [0.53, 0.76]) and B (OR=0.71, 95%CI [0.64, 0.80]) but not vitamins C (OR=0.69, 95%CI [0.48, 1.01]), D (OR=0.90, 95%CI [0.45, 1.83]), or E (OR=0.91, 95%CI [0.71, 1.16]) was associated with a low prevalence of glaucoma. The results of this study demonstrated that high-dose intake of vitamins A and B, but not vitamins C, D, or E, was associated with a low prevalence of glaucoma.

[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.

[Association between education and the onset of disability in activities of daily living in middle-aged and older Chinese adults: The mediator role of social participation].

OBJECTIVE: To investigate the association between educational attainment and the onset of disability in activities of daily living (ADL), and to explore the mediating effect of social participation on such association. METHODS: A longitudinal dataset was drawn from the China Health and Retirement Longitudinal Study (CHARLS, 2015 to 2018). The measurements of educational attainment, social participation and other covariates were identified from 2015, while the outcome measurement of ADL disability was constructed with data from survey 2018. Descriptive analyses were conducted, and basic characteristics and social engagement of the respondents were compared between illiterates and non-illite-rates using Chi-square test. Logistic regression was used to investigate the associations of educational attainment and social participation on the onset of ADL disability. Mediation analysis was employed to examine the mediator role of the social participation on the linkage from being illiterate to the ADL disability onset. RESULTS: A total of 11 359 adults aged 45 years and above were included in the sample, of whom 3 222 were illiterates. The incidence of the onset of ADL disability of illiterates and non-illiterates were 10.4% and 6.2%, respectively. Among these respondents, only half of them were involved in social activities. Of all the 8 social activities, the percentage of interacting with friends (34. 1%) was the highest, and the lowest percentage was observed in participating in an educational or training course (0.6%). Moreover, the percentages of participation in all these 8 social activities among illiterates were significantly lower than that of their educated counterparts (all P < 0.001). The illiterate middle-aged and older adults were less likely to develop ADL disability in the follow-up period [adjusted odds ratio (aOR)=1.22, 95%CI: 1.02-1.45], and social participation was significantly associated with ADL disability onset (aOR=0.73, 95%CI: 0.63-0.85). Findings from mediation analysis illustrated that social participation accounted for 12.22% of the adverse effect of being illiterate on ADL disability onset. CONCLUSION: Social participation could buffer the negative effect of being illiterate on ADL disability onset in middle-aged and older adults, suggesting that engagement in social activities might have impact on prevention of impairments in physical function, especially for middle-aged and older illiterates.

[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.

Effect of RMT1-10 on the immunological characteristics of dendritic cells cultured in vitro and corneal transplantation in vivo.

OBJECTIVE: Corneal allograft rejection is an immunological hypersensitive reaction caused by the antigenicity of the donor cornea. This study aimed to explore the effects of RMT1-10 on the prevention of corneal graft rejection by modifying immunological characteristics of dendritic cells (DCs). MATERIALS AND METHODS: DCs and CD4+T cells were sorted using flow cytometry and used for in vitro mixed lymphocyte culture. The cultured cells were prepared for the characterization of the DC cell phenotypes using the markers CD11c, CD80, MHC II, CD54, and TIM-4. Cytokine concentrations of IL-4, IL-12, and IL-10 of supernatants were measured by the enzyme-linked immunosorbent assay. CD4+T cells were examined by flow cytometry for apoptosis and proliferation. We also investigated the effect of RMT1-10 in the prevention and treatment of high-risk corneal graft rejection using a mouse model of corneal transplantation. RESULTS: DCs were identified as the CD11c+MHC-II-expressing subset. RMT1-10 suppressed the expression of CD11c, CD80, MHC II, CD54, and TIM-4 of DCs using the blockade of TIM-1 signaling. Moreover, TIM-1 blockade inhibited the production of IL-12 and IL-10 in a mixed lymphocyte culture system. However, a TIM-1 blockade had no effect on the apoptosis of CD4+T cells. RMT1-10 suppressed DC maturation, inhibiting the proliferation of CD4+T cells. CONCLUSIONS: RMT1-10 significantly improved the survival rate of the corneal allografts in mice compared with saline-injected controls. This clinical improvement from RMT1-10 occurred through the inhibition of CD4+T cell proliferation. Moreover, RMT1-10 induced antigen-specific detection of receptor immune tolerance. The cross-linking of TIM-1 on CD4+T cells with the agonist mAb provided a costimulatory inhibition signal for T cell activation or proliferation.

[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.

[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.

[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.

[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.

[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.

[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.

[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.

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.