OBJECTIVE: To determine the prevalence of GJB2 gene c.109G>A (p.V37I) variant among infants with congenital hearing loss and analyze the initial audiological characteristics of children harboring the variant, compare the audiometric difference among individuals with various genotypes, and explore genetic and audiological manifestations of the affected families. METHODS: One hundred twenty six infants diagnosed with congenital hearing loss at the Neonate Screening Center of Ningbo City from June 2021 to December 2024 were selected as the study subjects. The neonates, in addition with members from 16 of their families, had undergone genetic screening for variants of 208 hotspot sites within 24 deafness-associated genes. For cases identified with monoallelic variants and concurrent hearing loss, the full GJB2 gene was sequenced. Meanwhile, a retrospective analysis was carried out on 23 children whom were confirmed to have hearing loss and the c.109G>A variant by whole exome sequencing from March 2022 to December 2024. And 102 children who were excluded to have hearing loss and pathogenic variants by whole exome sequencing were selected as normal controls. Audiological features of individuals harboring the c.109G>A variant were compared. This study has been approved by the Medical Ethics Committee of The Affiliated Women and Children's Hospital of Ningbo University (Ethics No.: EC2023-009). RESULTS: For the 126 infants with congenital hearing loss, prospective screening has identified 58 (46.03%) to harbor the c.109G>A variant. These included 38 homozygotes and 16 compound heterozygotes. Retrospective review of the 23 c.109G>A positive children has identified 15 as homozygotes and 8 as compound heterozygotes. Genetic testing of the 16 pedigrees has identified 7 homozygotes and 1 compound heterozygote. For the homozygotes combined (n = 53), 96.2% exhibited bilateral symmetric hearing loss, with 78.3% showing high-frequency sloping patterns, and 98.1% having a hearing threshold ranging from 20 to 65 dB. For the compound heterozygotes combined (n = 24), 95.8% showed symmetric loss, with 59.4% having high-frequency sloping, and 97.9% had a hearing threshold ranging from 20 to 65 dB. Both groups showed significantly elevated ABR/PTA thresholds compared with the normal controls (P = 0.000). The compound heterozygous group had higher ABR thresholds (43.3 ± 15.0 dB nHL) compared with the homozygous group (39.1 ± 12.0 dB nHL, P = 0.005). CONCLUSION Infants harboring the GJB2 c.109G>A variant primarily manifest as mild-to-moderate, symmetric, high-frequency sloping hearing loss. Nearly one-third of affected children have thresholds between 20 to 35 dB nHL, suggesting that ABR > 35 dB nHL alone may underestimate the hearing impairment in this population. Compared with homozygotes, compound heterozygotes with the the GJB2 c.109G>A variant can confer a more severe hearing loss.
Humans ; Connexin 26/genetics* ; Female ; Male ; Infant, Newborn ; Infant ; Hearing Loss/genetics* ; Retrospective Studies ; Child, Preschool ; Child ; Genotype ; Connexins/genetics* ; Mutation

Objective To study the chemical constituents from the herbs of Dendrobium crepidatum and identify its antitumor bioactive compounds.Methods The constituents were extracted by methyl alcohol and isolated by CC and Sephadex LH-20.Their structures were identified by spectroscopic analysis(1H NMR,13CNMR and EIMS).The antitumor activity of the constituents was determined by MTT assay in vitro.Results 9 compouds were obtained and identified as p-hydroxybenzaldehyde(1),p-methoxyphenol(2),p-Hydroxybenzyl alcohol(3),hydroquinone(4),(24R)-ethylcholest-5-en-3-ol-7-one(5),sinalexin(6),bis(2-ethylhexyl)benzene-1,2-dicarboxylate(7),pinoresinol(8),Chaenomin B(9).The antitumor activity of compounds 5～9 was tested,and it was found that compound 9 had good inhibitory activity against A549 cell line.Conclusion Compounds 2～5,7～8 were isolated from the herbs for the first time and compounds 6,9 were isolated from this genus for the first time.IC50 of 9 on A549 cell line is 29.35 μM.

Objective To observe clinical effects of the modified nasopharyngeal airway tube combined with intubation soft lens in endotracheal intubation.Methods Two hundred patients who were to receive surgery were chosen as research subjects.With the knowledge and consent of the patients and following the signing of the letter of agreement,the patients were divided into 4 groups:group A,B,C and D,each consisting of 50 patients.For the patients of group A and B,endotracheal intubation was performed by high-qualified anesthesiologists (with the certificate of medical practitioner for over 5 years),while for the patients of group C and D,intubation was done by low-qualified ones (with the certificate of medical practitioner for less than 5 years).For the patients of group A and C,nasopharyngeal airway tube was placed through the approach of side nasal cavity following anesthesia induction,and then soft lens was used to complete endotracheal intubation via nasopharyngeal airway.For the patients of group B and D,soft lens intubation was performed directly through nasal cavity following anesthesia induction.Medical data,such as intubation time,number of intubation,first time of glottis exposure,cases of intubation failure,and adverse reactions or complications induced by intubation were recorded for further analysis.Results The intubation time of group A was shorter than that of group 13,and the time of group C was shorter than that of group D,and statistical significance could be seen,when comparisons were made between them(P ＜ 0.05).The success rate at the first try of intubation for group A and C were respectively 84％ and 82％,and the failure rate was all 2％,while for group B and D the success rate of intubation were respectively 50％ and 30％,and failure rates were respectively 10％ and 20％.Statistical significance could be noticed,when comparisons were made between the groups,i.e.between group A and B,between group C and D and also between group B and D (P ＜ 0.05).Conclusion Modified nasopharyngeal airway tube combined with intubation soft lens could obviously shorten endotracheal intubation time and increase the success rate of intubation.No significant differences could be noted in intubation time and failure rate,when the use of modified nasopharyngeal airway tube was combined with intubation soft lens by high-qualified and low-qualified anesthesiologists.