OBJECTIVE: To compare the biomechanical properties of four internal fixation methods in a lower cervical spine injury model using the finite element method. METHODS: Cervical CT data of a 28-year-old healthy adult male were utilized to establish a finite element model of the normal cervical spine and a lower cervical spine three-column injury model. Four internal fixation methods were then applied to the three-column injury model, resulting in four groups:Group A, anterior cervical locked-plate(ACLP) fixation system model(anterior approach);Group B, posterior cervical pedicle screw fixation model (posterior approach);Group C, combined anterior and posterior cervical pedicle screw fixation model; Group D, Novel composite anterior cervical internal fixation model. A 75 N axial compressive load and a 1.0 N·m pure moment were applied to the upper surface of the cervical spine model to simulate flexion, extension, rotation, and lateral bending movements. The intervertebral range of motion(ROM) and stress distribution of the internal fixators under different motion conditions were compared across all models. RESULTS: Compared with the normal model, the reductions in overall intervertebral ROM for each group under flexion, extension, rotation, and lateral bending were as follows:Group A, 24.04°, 23.12°, 6.24°, and 9.06°;Group B, 24.42°, 24.34°, 6.48°, and 9.20°;Group C, 25.43°, 25.29°, 7.17°, and 9.57°;Group D, 24.75°, 25.5°, 6.71°, and 9.12°. The peak stress values of the internal fixators in each group were:Group A, 53.9 MPa, 79.9 MPa, 61.4 MPa, and 80.3 MPa;Group B, 218.3 MPa, 105.4 MPa, 206.6 MPa, and 186.8 MPa;Group C, 40.8 MPa, 97.2 MPa, 47.1 MPa, and 39.4 MPa;Group D, 93.0 MPa, 144.0 MPa, 64.8 MPa, and 106.3 MPa. CONCLUSION The biomechanical properties of the novel composite anterior cervical internal fixation method are similar to those of the combined anterior-posterior fixation method, and superior to both the anterior cervical ACLP plate-screw fixation and posterior cervical pedicle screw fixation methods.
Humans ; Finite Element Analysis ; Cervical Vertebrae/physiopathology* ; Male ; Biomechanical Phenomena ; Adult ; Fracture Fixation, Internal/methods* ; Range of Motion, Articular

Extensive studies have identified potential adverse effects on semen quality of obesity, based on body mass index, but the association between body fat distribution, a more relevant indicator for obesity, and semen quality remains less clear. We conducted a longitudinal study of 4304 sperm donors from the Guangdong Provincial Human Sperm Bank (Guangzhou, China) during 2017-2021. A body composition analyzer was used to measure total and local body fat percentage for each participant. Generalized estimating equations were employed to assess the association between body fat percentage and sperm count, motility, and morphology. We estimated that each 10% increase in total body fat percentage (estimated change [95% confidence interval, 95% CI]) was significantly associated with a 0.18 × 10 6 (0.09 × 10 6 -0.27 × 10 6 ) ml and 12.21 × 10 6 (4.52 × 10 6 -19.91 × 10 6 ) reduction in semen volume and total sperm count, respectively. Categorical analyses and exposure-response curves showed that the association of body fat distribution with semen volume and total sperm count was stronger at higher body fat percentages. In addition, the association still held among normal weight and overweight participants. We observed similar associations for upper limb, trunk, and lower limb body fact distributions. In conclusion, we found that a higher body fat distribution was significantly associated with lower semen quality (especially semen volume) even in men with a normal weight. These findings provide useful clues in exploring body fat as a risk factor for semen quality decline and add to evidence for improving semen quality for those who are expected to conceive.
Humans ; Male ; Adult ; Semen Analysis ; China ; Body Fat Distribution ; Longitudinal Studies ; Sperm Count ; Sperm Motility ; Body Mass Index ; Tissue Donors ; Obesity/complications* ; Spermatozoa ; Young Adult ; Middle Aged ; East Asian People

OBJECTIVES: To study the clinical characteristics, efficacy, and prognosis of pediatric Langerhans cell histiocytosis (LCH). METHODS: A retrospective analysis was conducted on 72 children with newly diagnosed LCH. RESULTS: The median age of the 72 children was 5 years (range: 0-14 years), with skull involvement being the most common (56 cases, 77.8%). The BRAF-V600E mutation was not associated with clinical characteristics, efficacy, or prognosis (P>0.05). The 5-year overall survival rate was 91.6%±4.2%, and the 5-year event-free survival (EFS) rate was 67.5%±5.8%. The 6-week chemotherapy response rate and 5-year EFS rate were lower in the risk organ involvement group compared to the no risk organ involvement group (P<0.05). The five-year overall survival rates for the group with multi-system involvement and the group with platelet count ≥450×10⁹/L were respectively lower than those for the single-system involvement group and the group with platelet count <450×10⁹/L (P<0.05). Risk organ involvement is an independent risk factor for 5-year EFS (P<0.05). CONCLUSIONS Skull is the most commonly affected site in pediatric LCH. The BRAF-V600E mutation is not related to clinical characteristics, efficacy, or prognosis. Elevated platelet count, risk organ involvement, and multisystem involvement are associated with poor prognosis, with risk organ involvement being an independent risk factor for 5-year EFS.
Humans ; Histiocytosis, Langerhans-Cell/therapy* ; Child, Preschool ; Child ; Male ; Infant ; Female ; Adolescent ; Retrospective Studies ; Proto-Oncogene Proteins B-raf/genetics* ; Prognosis ; Infant, Newborn ; Mutation

OBJECTIVE: To investigate the effects of acupuncture on the neurotransmitter levels and gut microbiota in a mouse model of Tourette syndrome (TS). METHODS: Thirty-six male C57/BL6 mice were randomly divided into 4 groups using a random number table method: 3,3'-iminodipropionitrile (IDPN) group, control group, acupuncture group, and tiapride group, with 9 mice in each group. In the IDPN group, acupuncture group, and tiapride group, mice received daily intraperitoneal injections of IDPN (300 mg/kg body weight) for 7 consecutive days to induce stereotyped behaviors. Subsequently, in the acupuncture intervention group, standardized acupuncture treatment was administered for 14 consecutive days to IDPN-induced TS model mice. The selected acupoints included Baihui (DU 20), Yintang (DU 29), Waiguan (SJ 5), and Zulinqi (GB 41). In the tiapride group, mice were administered tiapride (50 mg/kg body weight) via oral gavage daily for 14 consecutive days. The control group, IDPN group, and acupuncture group received the same volume of saline orally for 14 consecutive days. Stereotypic behaviors were quantified through behavioral assessments. Neurotransmitter levels, including dopamine (DA), glutamate (Glu), and aspartate (ASP) in striatal tissue were measured using enzyme-linked immunosorbent assay. Dopamine transporter (DAT) expression levels were additionally quantified through quantitative polymerase chain reaction (qPCR). Gut microbial composition was analyzed through 16S ribosomal RNA gene sequencing, while metabolic profiling was conducted using liquid chromatography-mass spectrometry (LC-MS). RESULTS: Acupuncture administration significantly attenuated stereotypic behaviors, concurrently reducing striatal levels of DA, Glu and ASP concentrations while upregulating DAT expression compared with untreated TS controls (P<0.05 or P<0.01). Comparative analysis identified significant differences in Muribaculaceae (P=0.001), Oscillospiraceae (P=0.049), Desulfovibrionaceae (P=0.001), and Marinifilaceae (P=0.014) following acupuncture intervention. Metabolomic profiling revealed alterations in 7 metabolites and 18 metabolic pathways when compared to the TS mice, which involved various amino acid metabolisms associated with DA, Glu, and ASP. CONCLUSIONS Acupuncture demonstrates significant modulatory effects on both central neurotransmitter systems and gut microbial ecology, thereby highlighting its dual therapeutic potential for TS management through gut-brain axis regulation.
Animals ; Tourette Syndrome/metabolism* ; Gastrointestinal Microbiome ; Neurotransmitter Agents/metabolism* ; Acupuncture Therapy ; Male ; Mice, Inbred C57BL ; Mice

Cemental tear is a rare and indetectable condition unless obvious clinical signs present with the involvement of surrounding periodontal and periapical tissues. Due to its clinical manifestations similar to common dental issues, such as vertical root fracture, primary endodontic diseases, and periodontal diseases, as well as the low awareness of cemental tear for clinicians, misdiagnosis often occurs. The critical principle for cemental tear treatment is to remove torn fragments, and overlooking fragments leads to futile therapy, which could deteriorate the conditions of the affected teeth. Therefore, accurate diagnosis and subsequent appropriate interventions are vital for managing cemental tear. Novel diagnostic tools, including cone-beam computed tomography (CBCT), microscopes, and enamel matrix derivatives, have improved early detection and management, enhancing tooth retention. The implementation of standardized diagnostic criteria and treatment protocols, combined with improved clinical awareness among dental professionals, serves to mitigate risks of diagnostic errors and suboptimal therapeutic interventions. This expert consensus reviewed the epidemiology, pathogenesis, potential predisposing factors, clinical manifestations, diagnosis, differential diagnosis, treatment, and prognosis of cemental tear, aiming to provide a clinical guideline and facilitate clinicians to have a better understanding of cemental tear.
Humans ; Dental Cementum/injuries* ; Consensus ; Diagnosis, Differential ; Cone-Beam Computed Tomography ; Tooth Fractures/therapy*

Gastric cancer with peritoneal metastasis (GCPM) is a common and lethal manifestation of advanced gastric cancer, with a median survival of only 5-11 months. This consensus was developed by 30 experts from Asia (China, Japan, Korea, and Singapore) using the Delphi method and the GRADE evidence grading system. A total of 29 statements were formulated, covering the diagnosis and assessment of GCPM, indications for laparoscopic exploration and NIPS (normothermic intraperitoneal and systemic treatment), treatment regimens, prevention and management of complications, criteria for conversion surgery, and postoperative intraperitoneal therapy. The consensus aims to standardize clinical practice and improve the prognosis of patients with GCPM.

Objective To analyze the relationship between frailty and acute kidney injury(AKI)after hip fracture surgery in the elderly.Methods A total of 405 elderly patients who underwent hip fracture surgery in Jieyang People's Hospital from August 2021 to January 2023 were retrospectively analysed.According to the modified frailty index(mFI),they were divided into frail group(mFI≥0.27,n=112)and non-frail group(mFI<0.27,n=293).Postoperative AKI was defined according to the Kidney Disease:Improving Global Outcomes(KDIGO)criteria.After 1:1 propensity score matching(PSM),100 cases in each group were successfully matched.Univariable and multivariable logistic regression models,propensity score adjustment,PSM,inverse probability of treatment weighting(IPTW),standardized mortality ratio weighting(SMRW),pairwise algorithm(PA)weighting,and overlap weighting(OW)methods were used to analyze the relationship between frailty and postoperative AKI.Stratified analyses were performed according to age(≥80 or<80 years),gender,whether angiotensin-converting enzyme inhibitors(ACEI)/angiotensin Ⅱreceptor antagonists(ARB)were used,and whether intraoperative hypotension occurred.Results After PSM,there were no significant differences between the two groups in age,sex,surgical type,ACEI/ARB,blood urea nitrogen,serum creatinine,intraoperative blood loss,and intraoperative hypotension[standardized mean difference(SMD)<0.1].In both the original cohort and the matched cohort,the incidence of AKI was higher in frail group than in non-frail group(25.9%vs.8.9%,P<0.001;28.0%vs.11.0%,P=0.002).Analysis of the risk of postoperative AKI in elderly hip fracture patients in frail group found that compared with the non-frail group,in the univariate logistic regression model the odds ratio(OR)and a 95%confidence interval(CI)for the frail group was 3.59(2.00-6.43),P<0.001,and in the multivariable logistic regression model,the OR(95%CI)for frail group was 3.04(1.55-5.95),P=0.001.After adjustment for propensity score,the OR(95%CI)for frail group was 2.85(1.52-5.34),P=0.001,and the OR(95%CI)for frail group after PSM was 3.15(1.47-6.75),P=0.003.After IPTW,SMRW,PA weighting,and OW,the OR(95%CI)for frail group were 2.48(1.37-4.50),2.43(1.41-4.19),2.63(1.25-5.54),and 2.69(1.07-6.78),respectively,with P<0.05.The interaction tests were not statistically significant for age,sex,use of ACEI/ARB,and intraoperative hypotension(P>0.05).Conclusion In elderly patients with hip fractures,preoperative frailty may be a risk factor for postoperative AKI.

Objective To investigate the feasibility of mimics software in analyzing a new type of complex anterior cervical fixation—anterior transpedicular screw fixation+zero notch internal fixation.Methods From January 2021 to September 2022,50 normal pedestrians who underwent cervical spine CT scanning were selected for C1-C7 segment scanning,including 27 males and 23 females,aged from 25 to 65 years old with an average of(46.0±9.0)years old.The dicom format is exported and engraved into the CD,and use the mimics software to perform 3D reconstruction of each segment.A simulated screw is placed on the image according to the critical value of zero notch screw(head and tail angle 44°,internal angle 29°).The posi-tion of zero notch screw in each segment is observed to determine the feasibility of anterior transpedicular screw fixation plus zero notch internal fixation.Results For the upper zero notch screws the three-dimensional images of the cervical spine across all 50 subjects within the C3-C7 segments demonstrated safe position,wwith no instances of intersection with ATPS.For the lower zero notch screw,in C3-C4 and C4-C5,4 out of 50 subjects are in the safe position in the three-dimensional images of cervical ver-tebrae,and 46 cases could achieve secure screw placement when the maximum caudal angle is(32.3±1.9)° and(36.1±2.2)°,respectively.In C5-C6 and C6-C7 segments,no lower zero notch screws intersected with ATPS,and all screws are in safe posi-tions.Conclusion Lower cervical anterior pedicle screw fixation plus zero notch internal fixation can achieve successful nail placement through the selected entry point and position.

Objective To detect the changes of mitophagy level in rats with endplate cartilage degeneration induced by spinal instability,and explore the role of PINK1/Parkin-mediated mitophagy in endplate cartilage and intervertebral disc degeneration.Methods The rat spinal instability model was established by surgically removing the superspinal and interspinal ligaments of L2 to L5,and cleaning the bilateral articular processes of the L2 to L5.Eighteen SD rats were divided into the normal group,the degenerative group,and the carbonyl cyanide 3-chlorophenylhydrazone(CCCP)group,with 6 rats in each group.The rats in the normal group had no special treatment,the rats in the degenerative group constructed a rat spinal instability model,and the rats in the CCCP group were injected with 5 μL of CCCP(10 μmol/L)in the intervertebral disc after the construction of spinal instability model.The changes of histomorphology in the endplate cartilage and intervertebral disc were abserved by HE staining,and the change of extracellular matrix of endplate cartilage was observed by safranin O-fast green staining.RT-PCR detected the mRNA expression of type Ⅱ collagen(COL-2A),aggrecan(ACAN),PINK1 and Parkin in each group.The changes of the protein expression levels of COL-2A,ACAN,PINK1,Parkin and mitochondrial membrane proteins of Tomm20 and Timm23 were detected by Western blot.Results Compared with the normal group,the intervertebral disc nucleus pulposus of rats in the degenerative group was significantly destroyed and the secretion of extracellular matrix of endplate chondrocytes decreased;while the structure of intervertebral discs for rats in the CCCP group was more intact,and the secretion of extracellular matrix of endplate chondrocytes was significantly increased compared with that in the degenerative group.Compared with the normal group,the expression of COL-2A and ACAN in endplate cartilage tissues of rats in the degenerative group were significantly down-regulated(P<0.05),the expression of mitochon-drial autophagy-related genes of PINK1 and Parkin were significantly decreased(P<0.05),and the expression of mitochondrial membrane proteins of Tomm20 and Timm23 were increased(P<0.05).Compared with the degenerative group,the expression of COL-2A,ACAN,PINKI and Parkin in the endplate cartilage tissue of rats in the CCCP group were significantly up-regulated(P<0.05),and the protein levels of Tomm20 and Timm23 were significantly down-regulated(P<0.05).Conclusion Rat spinal instability leads to a decrease level of mitophagy mediated by PINK1/Parkin signaling pathway in endplate cartilage,thereby inducing endplate cartilage and intervertebral disc degeneration,and the activation of mitophagy can significantly reduce endplate cartilage and intervertebral disc degeneration.

Due to the high similarity with the lipid layer between human skin keratinocytes, functional cosmetics with layered liquid crystal structure prepared by liquid crystal emulsification technology encapsulating natural active substances have become a hot research topic in recent years. This type of functional cosmetic often has a fresh and natural skin feel, excellent skin barrier repair function and efficient moisturizing effect, etc., showing great potential in cosmetic application. However, the present research on the application of liquid crystal emulsification technology to functional cosmetics is still in the initial stage, and there are fewer relevant reports with reference values. Based on the mentioned above, this review provides a comprehensive summary of functional cosmetics with layered liquid crystal structures prepared by liquid crystal emulsification technology from the following aspects: the structure of human skin, the composition of lamellar liquid crystal, the advantages of liquid crystal emulsification technology containing natural active substances used in the field of functional cosmetics, the preparation process, main components, influencing factors during the preparation and the market functional cosmetics with lamellar liquid crystal structure. Finally, the prospect of the application of liquid crystal emulsification technology in functional cosmetics is presented, to provide useful references for those engaged in the research of liquid crystal emulsification technology-related functional cosmetics.