BACKGROUND:Gradient artificial bone repair scaffolds can mimic unique anatomical features in musculoskeletal tissues,showing great potential for repairing injured musculoskeletal tissues. OBJECTIVE:To review the latest research advances in gradient artificial bone repair scaffolds for tissue engineering in the musculoskeletal system and describe their advantages and fabrication strategies. METHODS:The first author of the article searched the Web of Science and PubMed databases for articles published from 2000 to 2023 with search terms"gradient,bone regeneration,scaffold".Finally,76 papers were analyzed and summarized after the screening. RESULTS AND CONCLUSION:(1)As an important means of efficient and high-quality repair of skeletal system tissues,gradient artificial bone repair scaffolds are currently designed bionically for the natural gradient characteristics of bone tissue,bone-cartilage,and tendon-bone tissue.These scaffolds can mimic the extracellular matrix of native tissues to a certain extent in terms of structure and composition,thus promoting cell adhesion,migration,proliferation,differentiation,and regenerative recovery of damaged tissues to their native state.(2)Advanced manufacturing technology provides more possibilities for gradient artificial bone repair scaffold preparation:Gradient electrospun fiber scaffolds constructed by spatially differentiated fiber arrangement and loading of biologically active substances have been developed;gradient 3D printed scaffolds fabricated by layered stacking,graded porosity,and bio-3D printing technology;gradient hydrogel scaffolds fabricated by in-situ layered injections,simple layer-by-layer stacking,and freeze-drying method;and in addition,there are also scaffolds made by other modalities or multi-method coupling.These scaffolds have demonstrated good biocompatibility in vitro experiments,were able to accelerate tissue regeneration in small animal tests,and were observed to have significantly improved histological structure.(3)The currently developed gradient artificial bone repair scaffolds have problems such as mismatch of gradient scales,unclear material-tissue interactions,and side effects caused by degradation products,which need to be further optimized by combining the strengths of related disciplines and clinical needs in the future.

Objective: To reveal the molecular biological mechanism of a rare Dc-variant individual using PacBio third-generation sequencing technology. Methods: ABO and Rh blood type identification, DAT, unexpected antibody screening and D antigen enhancement test were conducted by serological testing. The absorption-elution test was used to detect the e antigen. RHCE gene typing was performed by PCR-SSP, and the 1-10 exons of RHCE were sequenced by Sanger sequencing. The full-length sequences of RHCE, RHD and RHAG were detected by PacBio third-generation sequencing technology. Results: Serological findings: Blood type O, Dc-phenotype, DAT negative, unexpected antibody screening negative; enhanced D antigen expression; no detection of e antigen in the absorption-elution test. PCR-SSP genotyping indicated the presence of only the RHCE c allele. Sanger sequencing results: Exons 5-9 of RHCE were deleted, exon 1 had a heterozygous mutation at c. 48G/C, and exon 2 had five heterozygous mutations at c. 150C/T, c. 178C/A, c. 201A/G, c. 203A/G and c. 307C/T. Third-generation sequencing results: RHCE genotype was RHCE 02N. 08/RHCE-D(5-9)-CE; RHD genotype was RHD 01/RHD 01; RHAG genotype was RHAG 01/RHAG 01 (c. 808G>A and c. 861G>A). Conclusion: This Dc-individual carries the allele RHCE 02N. 08 and the novel allele RHCE-D(5-9)-CE. The findings of this study provide data support and a theoretical basis for elucidating the molecular mechanisms underlying RhCE deficiency phenotypes.

ObjectiveAs the central hub of the classical visual pathway, the primary visual cortex not only encodes and processes visual information but also establishes dense neural circuit connections with higher-order cognitive brain regions. Numerous studies have shown that 40 Hz flicker stimulation can induce γ oscillations in the brain and significantly improve learning and cognitive impairments in patients with neurodegenerative diseases. Moreover, flickering light phenomena naturally occur in daily environments. Given that the primary visual cortex serves as the brain’s first cortical hub for receiving visual input, it is essential to comprehensively understand how non-invasive light flicker stimulation modulates its information processing mechanisms. This study systematically investigates the effects of non-invasive light flicker stimulation at different frequencies on the functional properties of neurons in the primary visual cortex of adult mice, aiming to uncover how such stimulation modulates this region and, consequently, affects overall brain function. MethodsThree groups of adult mice (approximately 12 weeks old) were exposed to light flicker stimulation at frequencies of 20 Hz, 40 Hz, and 60 Hz, respectively, for a duration of two months. A control group was exposed to the same light intensity without flickering. Following the stimulation period, in vivo multi-channel electrophysiological recordings were conducted. During these recordings, anesthetized mice were presented with various types of moving sinusoidal light gratings to assess the effects of different flicker frequencies on the functional properties of neurons in the primary visual cortex. ResultsThe experimental results demonstrate that two months of light flicker stimulation at 20 Hz, 40 Hz, and 60 Hz enhances the orientation tuning capabilities of neurons in the primary visual cortex. Specifically, 40 Hz and 60 Hz stimulation improved contrast sensitivity, whereas 20 Hz had no significant effect. Further analysis revealed that all three frequencies reduced neuronal response variability (as measured by the Fano factor), increased the signal-to-noise ratio, and decreased noise correlation (r_sc) between neurons. ConclusionNon-invasive light flicker stimulation enhances orientation tuning (e.g., orientation bias index) and contrast sensitivity (e.g., contrast threshold and C₅₀) in neurons of the primary visual cortex. This enhancement is likely due to improved information processing efficiency, characterized by reduced neuronal variability and increased signal-to-noise ratio. These findings suggest that the primary visual cortex can achieve precise and efficient information encoding in complex lighting environments by selectively adapting to different flicker frequencies and optimizing receptive field properties. This study provides new experimental evidence on how various types of light flicker influence visual perception and offers insights into the mechanisms through which specific frequencies enhance brain function.

Objective To observe the clinical efficacy and safety of tofacitinib tablets combined with hydroxychloroquine tablets in the treatment of patients with refractory rheumatoid arthritis.Methods Patients with refractory rheumatoid arthritis were randomly divided into control and treatment groups.The control group was given enteric-coated sulfasalazine tablets 1.0 g per time,three times a day,orally+methotrexate tablets 10 mg per time,once a week,orally+hydroxychloroquine sulfate tablets 0.2 g per time,twice a day,orally.The treatment group received citrate tofacitinib tablets 5 mg per time,twice a day,orally,on the basis of control group.Two groups were treated for 6 months.The clinical efficacy,disease activity,joint pain level,rheumatoid factor(RF),and adverse drug reactions were compared between the two groups.Results Treatment group was enrolled 80 cases,4 cases dropped out,and 76 cases were included in the statistical analysis.Control group was enrolled 80 cases,8 cases dropped out,and 72 cases were included in the statistical analysis.After treatment,the total effective rates of treatment and control groups were 54.05％(40 cases/76 cases)and 16.22％(12 cases/72 cases)with significant difference(P＜0.05).After treatment,the disease activity score in 28 joints scores of treatment and control groups were(2.69±0.73)and(3.32±0.84)points;the visual analog scale scores were(2.72±0.71)and(3.31±0.68)points;the RF levels were(184.61±32.14)and(201.32±30.73)U·mL-1;the differences were statistically significant(all P＜0.05).The adverse drug reactions in the treatment group were gastrointestinal reactions,mild liver damage and elevated blood pressure,while those in the control group were gastrointestinal reactions and mild liver damage.The incidences of total adverse drug reactions in the treatment and control groups were 19.74％and 29.17％without significant difference(P＞0.05).Conclusion Tofacitinib tablets combined with hydroxychloroquine tablets have a definitive clinical efficacy in the treatment of refractory rheumatoid arthritis patients,which can significantly reduce the disease activity and relieve joint pain,without increasing the incidence of adverse drug reactions.

Objective To evaluate the bioequivalence of a single oral dose of ritonavir in fasted and fed conditions in healthy Chinese adult subjects with the test and reference formulations.Methods A single-center,open-label,randomized,single-dose,two-periods,two-sequence crossover design was used,and 64 subjects were enrolled in both the fasted and fed groups.The subjects received 100 mg of the test preparation or reference preparation orally per cycle,and the drug concentration of ritonavir in plasma was detected using the high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method.Pharmacokinetic parameters were estimated by a non-compartment model,and SAS 9.4 software was used for statistical analysis.Results Arithmetic mean values of the main pharmacokinetic parameters of the subject formulation of ritonavir tablets and the reference formulation in the fasting group:Cmax were(791.90±400.20)and(809.60±449.14)ng·mL-1;AUC0_t were(6 072.61±2 631.98)and(6 296.30±3 388.95)ng·h·mL-1;AUC0-∞ were(6 129.59±2 655.57)and(6 347.26±3 434.12)ng·h·mL-1,respectively.Arithmetic mean values of the main pharmacokinetic parameters of the subject formulation of ritonavir tablets and the reference formulation in the fed group:Cmax were(512.37±233.60)and(521.74±223.87)ng·mL-1;AUC0_t were(4 203.43±2 221.33)and(4 200.13±1 993.50)ng·h·mL-1;AUC0_∞ were(4 259.21±2 266.88)and(4 259.63±2 044.12)ng·h·mL-1.The 90％confidence intervals for the geometric mean ratios of Cmax,AUC0_t and AUC0_∞ of the prototype drug ritonavir in plasma after oral administration of 100 mg of the test and reference formulations of ritonavir tablets under fasting and fed conditions fell within the 80.00％to 125.00％equivalence interval.Conclusion The test and reference formulations of ritonavir tablets were bioequivalent under fasting and postprandial conditions.

Objective:This study aims to investigate the current application and the level of knowledge of intraoperative facial nerve monitoring among medical staff in China.Methods:A comprehensive online questionnaire was conducted among medical professionals across different regions in China from October 2022 to February 2023. The survey exclusively targeted departments specializing in otolaryngology, head and neck surgery, neurosurgery, and oral and maxillofacial surgery. The questionnaire covered various aspects including general information, intraoperative facial nerve monitoring practices, training history, indications for monitoring, parameters used during monitoring procedures, as well as factors influencing its implementation.Results:A total of 417 participants from 31 provincial, municipal, and autonomous regions were included. Intraoperative facial nerve monitoring was found to be implemented in 227 (54.4%,227/417) repondents of 53 institutions (24.9%, 53/213). The top three indications for implementing this technique were acoustic neuroma, parotid gland surgery, and modified middle ear surgery (mastoidectomy). Herein 81.1%(184/227) medical staff involved in intraoperative facial nerve monitoring had received relevant training, 57.3%(130/227)-92.1%(209/227) reported a lack of clear description regarding recording thresholds, stimulation currents/frequencies/wave widths.Conclusion:The majority of the institutions surveyed have not yet adopted intraoperative facial nerve monitoring. Furthermore, significant gaps concerning the procedure exist. It is imperative to establish standards or guidelines to promote its better development and application.

Following the principles of evidence-based medicine,in accordance with the structure and drafting rules of standardized documents,based on literature research,according to the characteristics of chronic cough in children and issues that need to form a consensus,the TCM Guidelines for Diagnosis and Treatment of Chronic Cough in Children was formulated based on the Delphi method,expert discussion meetings,and public solicitation of opinions.The guideline includes scope of application,terms and definitions,eti-ology and diagnosis,auxiliary examination,treatment,prevention and care.The aim is to clarify the optimal treatment plan of Chinese medicine in the diagnosis and treatment of this disease,and to provide guidance for improving the clinical diagnosis and treatment of chronic cough in children with Chinese medicine.

Objective To explore the regulatory effect of miR-6838-5p on DDR1 gene expression and proliferation of breast cancer cells.Methods The expression levels of miR-6838-5p in normal breast epithelial cells and breast cancer cells were detected using qRT-PCR,and the potential target genes of miR-6838-5p was predicted using TargetscanV 8.0.Double luciferase reporter gene experiment was performed to verify the binding between miR-6838-5p and DDR1.Breast cancer MCF-7 cells were transfected via liposome,miR-6838-5p mimic,miR-6838-5p inhibitor,DDR1 siRNA,DDR1-overexpresisng vector,or both miR-6838-5p mimic and DDR1-overexpressing vector,and the changes in cell proliferation were examined with CCK-8 and EdU assays;Western blotting was used to detect the expression of DDR1.The mediating role of DDR1 in miR-6838-5p overexpression-induced inhibition of MCF-7 cell proliferation was verified in a nude mouse model bearing MCF-7 cell xenografts.Results The expression of miR-6838-5p was significantly lower in breast cancer cells than in normal breast epithelial cells.In MCF-7 cells,miR-6838-5p overexpression induced significant inhibition of cell proliferation.Dual luciferase reporter gene experiment demonstrated a binding relationship between miR-6838-5p and DDR1(P<0.01).Western blotting showed that miR-6838-5p overexpression significantly lowered DDR1 expression in MCF-7 cells,and DDR1 overexpression promoted proliferation of the cells;co-transfection of the cells with DDR1-overexpressing vector significantly attenuated the inhibitory effect of miR-6838-5p mimic on cell proliferation.In the tumor-bearing nude mice,the xenografts overexpressing miR-6838-5p showed a significantly smaller volum with obviously the expression of DDR1.Conclusion Overexpression of miR-6838-5p inhibits breast cancer cell proliferation by regulating DDR1 expression.

Objective:To investigate the effects of marathon exercise on knee cartilage volume and T2 relaxation time (T2 value) based on MRI.Methods:From December 2018 to December 2021, 25 healthy volunteers without long-distance running habits and 32 non-professional marathon runners with long-term long-distance running were recruited to undergo knee MRI 3D water-selective excitation (three dimensional water-selective excitation, 3D-WATS) and T2 mapping imaging were performed, and the cartilage volumes in 5 knee areas and T2 values in 42 subareas were extracted for analysis. To compare the cartilage volume and its ratio to body surface area of knee joint of healthy volunteers and non-professional marathon runners, the T2 value of cartilage in each subregion, and the correlation between marathon exercise intensity and the volume and T2 value of cartilage in different regions.Results:Compared with healthy volunteers, there was no significant difference in cartilage volume or the ratio of body surface area to body volume of non-professional marathon runners ( P>0.05). There were significant differences between healthy volunteers and non-professional marathon runners in cartilage T2 values of the median layer of medial condyle of femur (47.61±5.65 ms and 44.29±6.10 ms) and the deep layer of medial condyle of femur (36.82±9.05 ms and 31.67±7.59 ms), deep precondylar area of medial femur (38.37±4.68 ms and 34.09±4.19 ms), shallow area of medial condylar area of femur (52.17±11.11 ms and 45.51±7.76 ms), middle layer of medial condylar area of femur (49.09±5.08 ms and 45.63±5.04 ms), medial layer of anterior condylar region of lateral femur (45.69±4.68 ms and 42.57±5.77 ms), superficial layer of posterior condylar region of lateral femur (55.42±18.41 ms and 47.99±8.39 ms), deep layer of anterior tibial medial plateau (33.40±7.76 ms and 29.03±5.69 ms), deep layer of posterior tibial medial plateau (31.28±5.02 ms and 27.92±5.99 ms), deep layer of patellofemoral surface (35.65±6.99 ms and 32.30±5.28 ms), respectively ( P<0.05). In non-professional marathon runners, the medial tibial plateau cartilage volume was negatively correlated with step frequency ( r=-0.371, P=0.035), the lateral femoral condylar cartilage volume was negatively correlated with step frequency ( r=-0.365, P=0.043), and the lateral tibial plateau cartilage volume was negatively correlated with step frequency ( r=-0.550, P=0.001). The T2 value of the medial layer cartilage in the anterior tibial medial plateau region was negatively correlated with body weight ( r=-0.277, P=0.039) and body mass index ( r=-0.290, P=0.030). The T2 value of the superficial layer of patellofemoral surface was negatively correlated with the amount of running in 3 months ( r=-0.457, P=0.010). The superficial T2 value in the posterior lateral plateau of the tibia was negatively correlated with stride length ( r=-0.437, P=0.014), and the medial layer cartilage T2 value in the anterior condylar area of the lateral femur was negatively correlated with stride frequency ( r=-0.380, P=0.035). Conclusion:Marathon exercise had little effect on the knee cartilage volume, but had a certain effect on the cartilage T2 value, resulting in changes in cartilage structure. The higher the step frequency, the smaller the cartilage volume. The greater the body weight or body mass index, the greater the amount of running in 3 months, and the greater the stride length, the lower the cartilage T2 value.

Background: Genetic defects in the human thyroid-stimulating hormone (TSH) receptor (TSHR) gene can cause congenital hypothyroidism (CH). However, the biological functions and comprehensive genotype–phenotype relationships for most TSHR variants associated with CH remain unexplored. We aimed to identify TSHR variants in Chinese patients with CH, analyze the functions of the variants, and explore the relationships between TSHR genotypes and clinical phenotypes. Methods: In total, 367 patients with CH were recruited for TSHR variant screening using whole-exome sequencing. The effects of the variants were evaluated by in-silico programs such as SIFT and polyphen2. Furthermore, these variants were transfected into 293T cells to detect their Gs/cyclic AMP and Gq/11 signaling activity. Results: Among the 367 patients with CH, 17 TSHR variants, including three novel variants, were identified in 45 patients, and 18 patients carried biallelic TSHR variants. In vitro experiments showed that 10 variants were associated with Gs/cyclic AMP and Gq/11 signaling pathway impairment to varying degrees. Patients with TSHR biallelic variants had lower serum TSH levels and higher free triiodothyronine and thyroxine levels at diagnosis than those with DUOX2 biallelic variants. Conclusions We found a high frequency of TSHR variants in Chinese patients with CH (12.3%), and 4.9% of cases were caused by TSHR biallelic variants. Ten variants were identified as loss-of-function variants. The data suggest that the clinical phenotype of CH patients caused by TSHR biallelic variants is relatively mild. Our study expands the TSHR variant spectrum and provides further evidence for the elucidation of the genetic etiology of CH.