Methods: The clinical data of 26 patients diagnosed with irreducible atlantoaxial dislocation complicated by atlantodental bony obstruction were analyzed retrospectively. All patients underwent anterior retropharyngeal atlantodentoplasty, followed by posterior occipitocervical fusion. Details including surgical duration and blood loss volume were recorded. Radiographic data such as the anterior atlantodental interval, O–C2 angle, space available for the cord, clivus–canal angle, and cervical medullary angle, and clinical data including the Japanese Orthopedic Association (JOA) score were assessed. The fusion time of the grafted bone and the development of complications were examined. Results: In patients undergoing anterior retropharyngeal atlantodentoplasty, the surgical duration and blood loss volume were 120.1±16.4 minutes and 100.6±33.5 mL, respectively. The anterior atlantodental interval decreased significantly after the surgery (p <0.001). The O–C2 angle, space available for the cord, clivus–canal angle, and cervical medullary angle increased significantly after the surgery (p <0.001). The JOA score during the latest follow-up significantly increased compared with that before the surgery (p <0.001). The improvement rate of the JOA score was 80.8%±18.1%. The fusion time of the grafted bone was 3–8 months, with an average of 5.7±1.5 months. In total, 11 patients presented with postoperative dysphagia and three with irritating cough. However, none of them exhibited other major complications. Conclusions Anterior retropharyngeal atlantodentoplasty can anatomically reduce the atlantoaxial joint with a satisfactory clinical outcome in patients with irreducible atlantoaxial dislocation with atlantodental bony obstruction.

Objective To investigate the effects of ischemia time and storage periods on RNA quality in fresh-frozen breast cancer(BC)and esophageal cancer(EC)tissue samples in order to establish evidence-based protocols for biobank sample management.Methods The tumor(T)and paired normal(N)tissue samples from 6 cases of BC and 6 cases of EC were collected and cryopreserved in Biobank,Shantou Central Hospital.Mirror paraffin-embedded tissues were simultaneously prepared into sections for morphological analysis.The samples were divided into two groups of<15 min and 15-30 min according to ischemia time,and RNA quality was analyzed at 4 storage periods of 8-10 months(T1),14-16 months(T2),26-28 months(T3)and 38-40 months(T4).Results In 96 analyzed samples,93.8%(90/96)exhibited high quality(RIN≥6),with 89.6%(43/48)in BC and 97.9%(47/48)in EC.Significant differences in RIN were observed between BC group and EC group(8.050 vs.8.600,P=0.009).In EC group,RIN value was significantly negatively correlated with RNA yield(P<0.001).Moreover,RIN values of tumor-normal pairs exhibited markedly significant differences(7.550 vs.9.000,P<0.001).In contrast,no significant difference was detected in BC group(8.200 vs.7.700,P=0.348).Statistical analysis showed that RIN value was positively correlated with 28S/18S(P<0.001),but had no correlation with tumor content(P=0.676)and necrotic content(P=0.055).Neither ischemia time(<15 min vs.15-30 min:8.200 vs.8.300,P=0.932)nor storage periods(T1-T4:8.400,7.700,8.450,8.600,P=0.163)compromised RNA quality.Conclusion Organ origin and tissue type could influence RNA quality of fresh-frozen tissue samples.However,limited ischemia time(≤30 min)and long-term storage period(38-40 months)do not adversely affect RNA quality in fresh-frozen breast cancer and esophageal cancer tissue samples.

Objective To propose a novel identification algorithm based on ensemble learning for assessing the severity of acute respiratory distress syndrome(ARDS)to achieve continuous monitoring of the disease severity.Methods Firstly,leve-raging the open-source MIMIC-Ⅳ database,a variety of non-invasive physiological parameters of patients were extracted and subjected to preliminary preprocessing.A multivariate feature selection algorithm was employed to rank these parameters and calculate feature importance scores through weighted computation.Secondly,based on the feature importance scores,a subset search algorithm was utilized to identify the subset of features that could yield optimal performance across four machine learning algorithms:neural networks,logistic regression,AdaBoost and XGBoost.Finally,a soft voting ensemble method was designed using a generalized linear regression model to integrate the results of each single machine learning algorithm,and a multivariate ensemble learning algorithm was proposed by combining the optimal feature subsets.The algorithm proposed when used to identify the severity of ADRS was evaluated with MIMIC-Ⅳ database,and compared with the traditional algorithms.Results The sensitivity,specificity,accuracy and AUC of the algorithm were 87.15％,89.23％,88.34％and 0.923 4,respectively,all of which outperformed those of the traditional algorithms.Conclusion The ARDS severity identification algorithm based on ensemble learning is capable of achieving continuous and real-time monitoring of the severity of ARDS,thereby offering robust support for the early identification and warning of ARDS in patients.[Chinese Medical Equipment Journal,2025,46(2):1-9]

Objective:To evaluate the safety and clinical efficacy of the navigation-assisted medial “in-out-in” technique in C 2 pedicle screw fixation. Methods:This study is a retrospective cohort study. The clinical data of 68 patients with high-riding vertebral arteries of the axis who underwent C 2 pedicle screw implantation using the medial “in-out-in” technique in the Department of Spinal Surgery, Henan Provincial People′s Hospital from August 2020 to July 2023 were retrospectively analyzed. There were 32 males and 36 females, with an age of (56.9±10.2) years (range: 35 to 78 years). Among them, 36 patients underwent navigation-assisted medial “in-out-in” technique for C 2 pedicle screw implantation and were included in the navigation group; 32 patients received freehand screw placement and were included in the freehand group. The operative time, intraoperative blood loss, postoperative maximum pedicle-screw distance (PSD max), bone graft fusion time, fusion rate, and occurrence of internal fixation-related complications were recorded and compared between the two groups. The spinal cord cross-sectional area (SSC) was measured before surgery and at 1 week after surgery. The atlanto-dental interval (ADI), clivus-canal angle (CCA), and Japanese Orthopaedic Association (JOA) score were evaluated before surgery, at 1 week, 3 months, 1 year after surgery, and at the final follow-up. Independent sample t-test, repeated measures analysis of variance, paired t-test, χ2 test, or Fisher′s exact test were used for data comparison. Results:Six patients with reduction blocked by atlanto-dental osteophytes first underwent anterior cervical atlanto-dental arthroplasty, followed by posterior surgery in the prone position, while the remaining 62 patients underwent posterior reduction and internal fixation. All 36 patients in the navigation group successfully completed C 2 medial “in-out-in” screw implantation, including 34 cases with unilateral medial ”in-out-in” screw implantation and 2 cases with bilateral implantation. In the freehand group, 28 cases completed medial “in-out-in” screw implantation, with 4 cases (12.5%) of implantation failure; the implantation failure rate in the navigation group was lower than that in the freehand group ( χ 2=5.027, P=0.025). The posterior surgical time in the navigation group was shorter than that in the freehand group ((158.1±25.7) minutes vs. (176.4±27.6) minutes, t=2.829, P=0.006), while there was no statistically significant difference in intraoperative blood loss during posterior surgery between the two groups ((217.5±62.2) ml vs. (212.7±53.2) ml, t=0.340, P=0.735). There was no significant change in SSC before and after surgery in both groups (all P>0.05). The postoperative JOA scores, ADI, and CCA in both the navigation group and the freehand group were significantly improved compared with those before surgery (all P<0.01), and there were no differences between the two groups (all P>0.05). The postoperative PSD max was (4.7±0.9) mm and the bone graft fusion time was (4.9±1.3) months in the navigation group, compared with (4.8±0.5) mm and (4.9±1.7) months in the freehand group, respectively; there were no statistically significant differences between the two groups (all P>0.05). During pedicle preparation, 1 case (2.8%) in the navigation group and 3 cases (9.4%) in the freehand group developed cerebrospinal fluid leakage due to dural puncture by the hand drill. One patient in the freehand group developed symptomatic cerebral infarction postoperatively, presenting with dysarthria, which recovered after medical treatment. There was no significant difference in the incidence of cerebrospinal fluid leakage or vertebral artery injury between the two groups. Conclusion:The navigation-assisted medial “in-out-in” technique enables safe and rapid implantation of three-column fixation screws in patients with high-riding vertebral arteries of the axis, with high accuracy in screw placement and satisfactory clinical outcomes.

A microchannel-based electrochemiluminescence(ECL)sensor was developed for detection of tetracycline(TC)utilizing luminol/H2O2 as ECL reporting system.The low excitation potential of luminol/H2O2 effectively mitigated the impact of clamping voltage,thereby enhancing the detection performance of the microchannel-based ECL sensor.The microchannel modified with TC aptamer selectively recognized and captured target TC.The positively charged TC reduced the surface charge density within the microchannel,thereby increasing the ionic current in the microchannel,leading to change of ECL signal of system.The experimental conditions such as electrolyte concentration,TC-aptamer concentration,and reaction time between TC and TC-aptamer were optimized.Under optimal conditions,the difference of ECL signal in the absence and presence of TC(?ECL)exhibited a good linear relationship with TC concentration in the range from 1.00 ng/mL to 200 ng/mL,with a detection limit as low as 0.69 ng/mL.The sensor had good selectivity and was successfully used in detection of TC in milk samples.

Methods: The clinical data of 26 patients diagnosed with irreducible atlantoaxial dislocation complicated by atlantodental bony obstruction were analyzed retrospectively. All patients underwent anterior retropharyngeal atlantodentoplasty, followed by posterior occipitocervical fusion. Details including surgical duration and blood loss volume were recorded. Radiographic data such as the anterior atlantodental interval, O–C2 angle, space available for the cord, clivus–canal angle, and cervical medullary angle, and clinical data including the Japanese Orthopedic Association (JOA) score were assessed. The fusion time of the grafted bone and the development of complications were examined. Results: In patients undergoing anterior retropharyngeal atlantodentoplasty, the surgical duration and blood loss volume were 120.1±16.4 minutes and 100.6±33.5 mL, respectively. The anterior atlantodental interval decreased significantly after the surgery (p <0.001). The O–C2 angle, space available for the cord, clivus–canal angle, and cervical medullary angle increased significantly after the surgery (p <0.001). The JOA score during the latest follow-up significantly increased compared with that before the surgery (p <0.001). The improvement rate of the JOA score was 80.8%±18.1%. The fusion time of the grafted bone was 3–8 months, with an average of 5.7±1.5 months. In total, 11 patients presented with postoperative dysphagia and three with irritating cough. However, none of them exhibited other major complications. Conclusions Anterior retropharyngeal atlantodentoplasty can anatomically reduce the atlantoaxial joint with a satisfactory clinical outcome in patients with irreducible atlantoaxial dislocation with atlantodental bony obstruction.

Methods: The clinical data of 26 patients diagnosed with irreducible atlantoaxial dislocation complicated by atlantodental bony obstruction were analyzed retrospectively. All patients underwent anterior retropharyngeal atlantodentoplasty, followed by posterior occipitocervical fusion. Details including surgical duration and blood loss volume were recorded. Radiographic data such as the anterior atlantodental interval, O–C2 angle, space available for the cord, clivus–canal angle, and cervical medullary angle, and clinical data including the Japanese Orthopedic Association (JOA) score were assessed. The fusion time of the grafted bone and the development of complications were examined. Results: In patients undergoing anterior retropharyngeal atlantodentoplasty, the surgical duration and blood loss volume were 120.1±16.4 minutes and 100.6±33.5 mL, respectively. The anterior atlantodental interval decreased significantly after the surgery (p <0.001). The O–C2 angle, space available for the cord, clivus–canal angle, and cervical medullary angle increased significantly after the surgery (p <0.001). The JOA score during the latest follow-up significantly increased compared with that before the surgery (p <0.001). The improvement rate of the JOA score was 80.8%±18.1%. The fusion time of the grafted bone was 3–8 months, with an average of 5.7±1.5 months. In total, 11 patients presented with postoperative dysphagia and three with irritating cough. However, none of them exhibited other major complications. Conclusions Anterior retropharyngeal atlantodentoplasty can anatomically reduce the atlantoaxial joint with a satisfactory clinical outcome in patients with irreducible atlantoaxial dislocation with atlantodental bony obstruction.

Aim To investigate the role and regulatory mechanism of CREB regulated transcription coactivator 2(CRTC2)in cardiomyocyte hypertrophy.Methods A pathological cardiomyocyte hypertrophy model was established in C57BL/6 mice by intraperitoneal injection of isoproterenol(ISO),the expression of CRTC2 in cardiac tissue was detec-ted by Western blot.The CRTC2 knockout mice model was constructed,the cardiac function of mice was detected by small animal echocardiography,the collagen fiber content in mice cardiac tissue was detected by Masson staining,the car-diomyocyte hypertrophy related proteins:skeletal muscle α1-actin(ACTA1)and brain natriuretic peptide(BNP),as well as ferroptosis related proteins:acyl-CoA synthetase long chain family member 4(ACSL4),solute carrier family 7 member 11(SLC7A11)and glutathione peroxidase 4(GPX4)in mice cardiac tissue were detected by Western blot,the iron ion content in mice cardiac tissue was detected by iron ion kit,to evaluate the correlation between CRTC2 and cardiomyocyte hypertrophy and ferroptosis.H9c2 cells were induced by ISO to construct an in vitro model of cardiomyocyte hypertrophy,the protein expressions of CRTC2,ACTA1,BNP,ACSL4,SLC7A11 and GPX4 were detected after intervention with fer-roptosis inhibitor ferrostatin-1(Fer-1).H9c2 cells with CRTC2 overexpression induced by ISO were used to construct an in vitro model of cardiomyocyte hypertrophy,the related indicators of cardiomyocyte hypertrophy and ferroptosis were detec-ted to explore the mechanism of CRTC2 in cardiomyocyte hypertrophy.Results Compared with the control group,the expression of CRTC2 protein in the cardiac tissue of ISO induced cardiomyocyte hypertrophy mice was increased(P＜0.05).Compared with wild-type mice,CRTC2-/-mice showed worsened cardiac function,manifested as increased left ventricular end-diastolic diameter(LVEDD),left ventricular end-systolic diameter(LVESD),left ventricular posterior wall thickness(LVPWT),heart weight/tibia length(HW/TL)and heart weight/body weight(HW/BW),decreased short axis shortening(FS)and ejection fraction(EF),increased collagen fiber content in cardiac tissue,upregulated ex-pression of cardiomyocyte hypertrophy-related proteins ACTA1 and BNP,increased mRNA and protein expression of ferrop-tosis-related protein ACSL4,decreased mRNA and protein expression of SLC7A11 and GPX4,and elevated iron ion content in cardiac tissue(P＜0.05 or P＜0.01).In vitro experiments showed that compared with ISO group,the ISO+Fer-1 group had no significant change in CRTC2 protein expression(P＞0.05),the expression of ACTA1 and BNP protein decreased,the surface area of cardiomyocyte reduced,the expression of ACSL4 protein decreased,and the expression of SLC7A11 and GPX4 proteins increased(P＜0.05 or P＜0.01).Compared with the ISO group,the LV-CRTC2+ISO group showed a decrease in surface area of cardiomyocytes(P＜0.01),a decrease in ACTA1,BNP and ACSL4 protein ex-pression,an increase in SLC7A11 and GPX4 protein expression,and a decrease in ROS and iron ion content(P＜0.05 or P＜0.01).Conclusion CRTC2 alleviates cardiomyocyte hypertrophy and protect cardiac function by suppressing fer-roptosis in cardiomyocytes.

Objective:To investigate spinal cord morphological changes and risk factors in upper cervical spine surgery using C 2 medial "in-out-in" pedicle screws in patients with atlantoaxial dislocation (AAD) and high-riding vertebral artery (HRVA). Methods:A retrospective analysis was conducted on 41 patients with AAD who underwent C 2 medial "in-out-in" pedicle screw implantation at our hospital between January 2019 and December 2023. The cohort included 12 males and 29 females, with a mean age of 47.6±10.3 years (range: 18-68 years). Among them, 30 patients received unilateral C 2 medial "in-out-in" screws, while 11 patients received bilateral screws. All patients underwent posterior reduction and internal fixation. Measurements included C 2 pedicle height, C 2 pedicle width, C 2 horizontal spinal canal width, screw invasion distance into the spinal canal, and spinal canal invasion rate based on CT findings. MRI evaluations included spinal canal-dura mater distance, dura mater-spinal cord distance, spinal canal-spinal cord distance, and spinal cord cross-sectional area. The change rate of spinal cord cross-sectional area was calculated and categorized into >20% decrease group (decreasing group) and ≤20% decrease group (non-decreasing group). Postoperative outcomes were assessed using the Visual Analogue Scale (VAS) and Japanese Orthopedic Association (JOA) scores. Results:The mean operative time was 165.5±30.1 minutes (range: 120-220 minutes). No spinal cord vascular injuries or severe complications were observed. However, five patients experienced cerebrospinal fluid (CSF) leakage, requiring delayed removal of drainage tubes, but their wounds healed successfully. Follow-ups (range: 6-24 months) showed no loosening of internal fixation, fractures, or bone graft nonunion, with a 100% bone fusion rate at 6 months postoperatively. VAS scores improved significantly from a preoperative median of 5.0 (3.5, 6.0) (range: 1-7) to 2.0 (2.0, 3.0) at 3 months and 1.0 (1.0, 1.0) at 6 months ( Z=36.716, P< 0.001). JOA scores improved from 10.0 (9.0, 12.0) (range: 4-14) preoperatively to 13.0 (11.0, 13.5) at 3 months and 14.0 (12.0, 15.0) at 6 months ( Z=67.093, P<0.001). The height of C 2 pedicle was 5.50±1.78 mm, the width of C 2 pedicle was 2.27±1.23 mm, the width of C 2 horizontal spinal canal was 23.76±4.91 mm, the spinal canal-dura mater distance was 3.08±0.85 mm, dura mater-spinal cord distance was 3.23±0.85 mm, the spinal canal-spinal cord distance was 6.31±1.11 mm, the distance of screw invasion into the spinal canal was 2.80±1.54 mm, the rate of spinal canal invasion was 12.1%±6.8%, the preoperative spinal cord cross-sectional area was 69.81±13.27 mm 2, and the postoperative spinal cord cross-sectional area was 68.81±13.94 mm 2. Based on spinal cord cross-sectional area changes, 32 patients were classified into the non-decreasing group, and 9 patients into the decreasing group. The intraclass correlation coefficient (ICC) values ranged from 0.733 to 0.984, indicating high measurement reliability. There were significant differences in the proportion of C 2 bilateral medial "in-out-in" screws (χ 2=6.903, P=0.009), the incidence of CSF leakage (χ 2=15.391, P<0.001), the distance of screw invasion into the spinal canal ( t=4.990, P<0.001) and the rate of spinal canal invasion ( t=4.045, P<0.001) in the decreasing group versus the non-decreasing group. The JOA scores of the non-decreasing group were significantly higher at 3 and 6 months postoperatively compared to the decreasing group ( P<0.05). No other parameters showed significant differences between the groups. Binary logistic regression analysis identified spinal canal invasion rate [ OR=1.963, 95% CI (1.010, 3.817), P=0.047] as an independent risk factor for spinal cord cross-sectional area reduction. The Jordan index was 0.875, with a spinal canal invasion rate threshold of 14.18%, a sensitivity of 1.000, a specificity of 0.875, and an AUC of 0.983, indicating strong predictive value. Conclusion:The C 2 medial "in-out-in" screw technique provides effective posterior fixation and fusion for AAD patients with HRVA. However, to minimize spinal cord morphological changes and associated risks, the spinal canal invasion rate should be kept below 14.18% when using this technique.