[Analysis of the characteristics of MRI T2 value changes of the muscles around the knee joint before and after the race in amateur marathon runners based on T2 mapping].

Objective: To evaluate the characteristics of MRI T2 value changes of muscles around the knee joint in amateur marathon athletes based on T2 mapping. Methods: A total of 12 amateur marathon runners (5 males and 7 females) were recruited as the marathon group, aged from 21 to 37(27.5±5.4) years. MRI examination of bilateral knee joint was performed one week before the race, within 12 hours after the race and two months after the race, respectively. Fifteen healthy volunteers (5 males and 10 females) were recruited as the control group, aged from 24 to 27(24.9±1.0) years, and underwent MRI examination of both knee joints. The T2 mapping imaging sequence was used to measure the T2 values of the sartorius, vastus medialis, biceps femoris, semimembranosus, medial head of gastrocnemius and lateral gastrocnemius head on the post-processing platform, and analyzed the marathon group before and after the race. The differences in the T2 value of each muscle of the marathon group before and after the race within 12 hours, before and 2 months after the race, and between the control group and the marathon group before the marathon were analyzed. Results: All subjects had not knee joint pain during the examination. Routine MRI examination showed that there was no obvious abnormality in the shape and signal of the muscles around the knee joint. The T2 value of the semimembranosus [(34.3±2.8) ms vs (35.5±2.5) ms, P=0.008], medial head of gastrocnemius [(34.1±3.4) ms vs (37.7±3.1) ms,P<0.001] and lateral head of gastrocnemius [(35.2±2.9) ms vs (37.2±3.9) ms,P=0.011] increased after the competition compared with that of pre-competition in the marathon group, while the T2 value of the remaining muscles showed no significant difference compared with that of pre-competition(P>0.05). At the follow-up of 2 months, the T2 value of semimembranosus remains higher than before the marathon [(34.3±2.8) ms vs (35.4±2.5) ms,P=0.043], and the T2 value of the medial head of the gastrocnemius and lateral head of gastrocnemius showed no statistically difference compared with pre-competition (P>0.05). Compared with the control group, the T2 value of the lateral head of the gastrocnemius in the marathon group was decreased [(35.3±3.0) ms vs (38.5±4.1) ms,P=0.007]. There was no significant difference in the T2 value of the remaining muscles in the marathon group (P>0.05). Conclusions: After the marathon, the changes in the T2 value of the muscles around the knee joint is reversible. T2 mapping imaging sequence can indirectly reflect the changes of skeletal muscle microstructure to a certain extent.

[Evaluation of refractory monosymptomatic nocturnal enuresis with ambulatory urodynamics monitoring and conventional urodynamics].

Objective: To explore the clinical value of ambulatory urodynamics monitoring (AUM) in the diagnosis and treatment of children with refractory monosymptomatic nocturnal enuresis (RMNE) by comparing the urodynamic parameters of AUM with those of conventional urodynamics (CUD). Methods: A total of 40 children (22 males and 18 females) diagnosed with RMNE in the First Affiliated Hospital of Zhengzhou University from May 2017 to September 2019 were collected. They were aged 9-16 years, and their frequency of nocturnal bed-wetting was≥2 times per week. CUD and one sleep cycle AUM were performed, respectively. Then, the urodynamic parameters were recorded and analyzed. Results: Five of the 40 children dropped out of the study because of the poor compliance. The age of children with RMNE was(12.6±2.1)years old, the ratio of male to female was 19∶16, and the severity of enuresis (enuresis frequency) was(4.2±1.7) times per week. Compared to the CUD group, the bladder compliance (BC) [(28.4±7.7) ml/cmH2O vs (23.6±6.1) ml/cmH2O(1 cmH2O=0.098 kPa)] and maximum detrusor pressure (Pmax.det) [(44.6±9.1) cmH2O vs (36.8±8.3) cmH2O] in the AUM group were significantly higher (P<0.05). The maximum flow rate (Qmax) [(19.6±7.2) ml/s vs (20.9±5.4) ml/s] and post void residual (PVR) [(9.5±5.7) ml vs (10.9±5.3) ml] between the two groups showed no statistically significant differences (P>0.05). Detrusor overactivity (DO) was detected in 27 cases (77.1%) during AUM and in 16 cases (45.7%) during CUD; the difference was statistically significant (P<0.05). Among them, 15 cases (42.9%) with DO were detected both in CUD and AUM, while 12 (34.3%) with DO were not detected in CUD. For the 15 cases with DO detected by both CUD and AUM, the frequency [(3.1±1.0) times/h vs (2.4±0.8) times/h] and maximum value of DO [(22.9±4.5) cmH2O vs (19.2±4.0) cmH2O] in the AUM group were both higher than those in the CUD group (P<0.05). Conclusions: Bladder dysfunction can be diagnosed in children with RMNE using AUM. Furthermore, AUM is more accurate than CUD in evaluating BC, Pmax.det, DO, and other parameters. For children with RMNE and with unsatisfactory CUD results, further AUM examination is recommended to clarify the etiology.

Purification and cloning of nicosulfuron-degrading enzymes from Bacillus subtilis YB1.

The nicosulfuron-degrading enzymes from Bacillus subtilis strain YB1 were purified and their genes were cloned. The proteins of bacterial culture filtrate were precipitated with ammonium sulfate or acetone. The extracellular proteins concentrated by acetone were purified from DEAE-Sepharose Fast Flow chromatography. The four protein peaks eluted from DEAE-column were separated and purified by native PAGE. Three components (P1-1, P3-2, P4-3) had nicosulfuron-degrading activity, and component P4-3 degradated 57.5% of this compound. The molecular weights of the components were 33.5, 54.8 and 37.0 kDa, respectively. The amino acid sequences of nicosulfuron-degrading enzymes from B. subtilis YB1 were determined by MALDI-TOF-MS, indicating these enzymes as manganese ABC transporter, vegetative catalase 1 and acetoin dehydrogenase E1, respectively. Using PCR amplification, genes 918, 1428, 1026 bp in size were detected for the enzymes studied.

[Evaluation of the outcomes of cochlear implant in children with auditory neuropathy].

Objective: To investigate the auditory and speech abilities of children with congenital auditory neuropathy (AN) after cochlear implant (CI), and to analyze the role of genetic testing in predicting the postoperative outcomes of CI in AN patients. Methods: Fourteen children diagnosed with AN by audiological battery test and underwent CI surgery in Xijing Hospital of the Air Force Medical University from 2002 to 2021 were included in this study (9 males and 5 females), with an implantation age of (3.1±1.7) years (mean±standard deviation, the same as follows). The preoperative audiological results and deafness gene results were analyzed. Another 52 children with ordinary sensorineural hearing loss (SNHL) were selected as the control group (30 males and 22 females), with an implantation age of (2.2±0.9) years. The demographic factors such as age and gender were matched with those of the AN group. The modified Category Auditory Performance (CAP-Ⅱ) and Speech Intelligence Rate (SIR) were used to evaluate the development of postoperative auditory and speech abilities in two groups. The Mandarin Speech Test System was used to test the speech recognition rate of monosyllabic and disyllabic words and sentences. Matlab 2022 software was used to analyze the data. Results: The results of gene in 14 children with AN showed that 6 cases had OTOF gene mutations, 2 cases (siblings) were confirmed to have TNN gene mutations through whole exome sequencing, and the remaining 6 cases were not find any clear pathogenic gene mutations. All subjects underwent CI surgery with electrodes implanted into the cochlea smoothly, and there were no postoperative complications. After surgery, all AN children had improved auditory and speech abilities, but only 64% (9/14) of AN children with CI had auditory ability scores comparable to the control group of SNHL children (including 2 children with TNN gene mutations), and 36% (5/14) of AN children had lower scores than the control group of SNHL children.The average speech recognition rate of two children with TNN gene mutations was 86.5%, and of two children with OTOF gene mutations was 83.2%. Conclusions: AN children achieved varying degrees of auditory and speech abilities after CI, but the postoperative effects varied greatly. Some children achieved similar results as ordinary SNHL children, but there were still some children whose effects were worse than those of ordinary SNHL children. The postoperative efficacy of CI in two children with AN caused by TNN pathogenic genes were comparable to that of ordinary SNHL in children. Genetic testing had certain reference value for predicting the postoperative effect of CI in AN children.

[Effectiveness and long-term stability of maxillary protraction].

Maxillary protaction is most commonly used for the treatment of growing skeletal class Ⅲ patients with a maxillary deficiency. The present article reviewed the advances in the use of maxillary protraction, including the case selection, the timing of the treatment, the effectiveness of rapid maxillary expansion, the pattern of the maxillary protraction and the long-term stability.

[The similarities and differences of mandarin open-set word recognition between cochlear implant children and normal hearing children].

Objective:To evaluate the ability of open-set word recognition in cochlear implant (CI) children,and compare the similarities and difference of open-set word recognition between CI children and normal hearing(NH) children.Method:This study included 485 children with CI and 162 children with NH, who completed the Mandarin lexical neighborhood test. The results for children at 1-8 years after receiving their CI were compared to those from the children with NH using analysis of variance.Result:There were significant differences in open-set word recognition between the CI and NH groups(P<0.05).For implantation before 2 years, there was no significant difference in recognition at the ages of 6-7 years,compared to 3-year-old children with NH, or at the age of 10 years, compared to 6-year-old children with NH(P>0.05).For implantation before 3 years, there was no significant difference in recognition at the ages of 8-9 years, compared to 3-year-old children with NH,or at the age of 10 years, compared to 6-year-old children with NH(P>0.05).For implantation after 3 years, there was a significant difference in recognition at the age of 13 years,compared to 3-year-old children with NH(P<0.05).Conclusion:Mandarin open-set word recognition increased with time after CI.Chinese children with CI had delayed but similar development of recognition, compared to normal children. Early CI can shorten the gap between children with CI and normal children.

Detection of fetal sex in the peripheral blood of pregnant women.

OBJECTIVE: To choose the best method to examine fetal sex in maternal blood as early as possible and evaluate the quantitative change of fetal-free DNA in maternal plasma. METHOD: One hundred and fifty pregnant women were studied at 5-9 completed weeks of gestation. Fetal cells were isolated using lymphocyte separation liquid and 3% gelatin. Furthermore, fluorescence in situ hybridization was used to examine the terminal of the Y chromosome. Nested polymerase chain reaction (PCR) and real-time fluorescence quantitative PCR (FQ-PCR) were used to amplify the SRY gene of the plasma DNA extracted from the same 150 samples of maternal blood. Sequential analysis was performed using FQ-PCR during the whole pregnancy on 32 pregnant women carrying male fetuses. RESULTS: Using fluorescence in situ hybridization, we can find male fetal cells in maternal blood as early as the 49th day. We can also find free fetal DNA in maternal plasma as early as the 49th and the 42nd day of pregnancy using nested PCR and FQ-PCR. The amount of fetal DNA was increasing with the gestation week. The standard value of every gestation week was obtained by FQ-PCR. CONCLUSION: FQ-PCR was the best method to detect fetal sex in early pregnancy. There is a principle of quantitative change of free fetal DNA in maternal plasma.

[Effects of noise competition on monosyllabic and disyllabic word perception in children].

Objective: The purpose of the present study was to investigate the effects of noise competition on word perception in normal hearing (NH) children and children with cochlear implantation (CI). Methods: To estimate the contribution of noise competition on speech perception, word perception in speech-shaped noise(SSN)and 4-talker babble noise(BN) with Mandarin Lexical Neighborhood Test were performed in 80 NH children and 89 children with CI. Corrected perception percentages were acquired in each group. Results: Both signal to noise ratio (SNR) and noise type influenced the word perception. In NH group, corrected percentages of disyllabic word perception in SSN were 24.2%, 55.9%, 77.1%, 85.1% and 88.9% at -8, -4, 0, 4 and 8 dB SNR, corresponding corrected percentages of monosyllabic word were 13.9%, 39.5%, 60.1%, 68.8% and 80.1%, respectively. In BN noise, corrected percentages of disyllabic word were 2.4%, 24.3%, 55.6%, 74.3% and 86.2%, corresponding monosyllabic word were 2.3%, 20.8%, 47.2%, 61.1% and 74.8%, respectively. In CI group, corrected percentages of dissyllabic word in SSN and BN at 10 dB SNR were 65.5% and 58.1%, respectively. Corresponding monosyllabic word were 49.0% and 41.0%. For SNR=5 dB, corrected percentages of disyllabic word in SSN and BN were 50.0% and 38.1%, corresponding corrected percentages of monosyllabic word were 40.8% and 25.1%, respectively. Analysis indicated that the masking effect were significantly higher in BN compared with SSN. Conclusions: Noise competition influence word perception performance significantly. In specific, the influence of noise on word perception is bigger in children with CI than in NH children. The masking effect is higher in BN noise when compared with SSN.

A maternal hereditary deafness pedigree of the A1555G mitochondrial mutation, causing aminoglycoside ototoxicity predisposition.

OBJECTIVE: To characterise the hearing loss, and the frequency of the mitochondrial deoxyribonucleic acid 12S ribosomal ribonucleic acid A1555G mutation, in a large pedigree of aminoglycoside-induced deafness. DESIGN: Hearing loss was clinically assessed. Blood samples were collected from 27 family members (19 matrilinear and eight non-matrilinear) and leukocyte deoxyribonucleic acid was extracted. Mitochondrial deoxyribonucleic acid fragments, spanning the 1555 location, were amplified by polymerase chain reaction. Polymerase chain reaction products were analysed by restriction fragment length polymorphism and deoxyribonucleic acid sequencing. RESULTS: We detected the A1555G mutation in all 19 matrilinear relatives. Of these 19, two exhibited congenital deafness, four had no hearing deficits and the remaining 13 suffered mild to profound hearing loss. CONCLUSION: We confirmed that the A1555G mutation is a 'hot spot' associated with non-syndromic, inherited hearing loss. This mutation may play a vital role in the pathogenesis of hearing impairment, and can result in various grades of deafness.

Methylation status of the fragile histidine triad and E-cadherin genes in plasma of cervical cancer patients.

Recent evidence suggests that tumor cells may release DNA into the serum and plasma of afflicted cancer patients. However, no report existed regarding the methylation status of the fragile histidine triad (FHIT) and E-cadherin genes in plasma samples of cervical cancer patients. Methylation-specific PCR (MSP) was employed to examine CpG island methylation of the FHIT and E-cadherin genes in 151 pretreatment plasma samples and 30 tumor tissue samples from cervical cancer patients. MSP products were cloned and sequenced. CpG island methylation of the FHIT and E-cadherin genes was detected in 30.46% and 39.74% of plasma samples, respectively, and in 53.33% and 60.0% of tissue samples, respectively. The total concordance rate of methylation between plasma samples and tissue samples in FHIT gene was 80.00% and that in E-cadherin gene was 76.66%. At least one of the two methylated genes was detected in 56.29% of plasma samples and 76.7% of tissue samples. The presence of both methylated genes was detected in 13.9% of plasma samples and 36.67% of tissue samples. We found that the higher the clinical stage and histologic grade, the higher the rate of methylation in both genes in plasma samples. CpG island methylation of the FHIT and E-cadherin genes is present in plasma of cervical cancer patients. Using the two genes as markers simultaneously may allow clinicians to diagnose and evaluate the effect of treatment earlier and using fewer invasive procedures.