Morphological classification and clinical significance of medial malleolus based on computed tomography three-dimensional reconstruction

BACKGROUND

Internal malleolus fractures and postoperative functional limitations are serious complications of deltoid ligament repair, reconstruction, while studies on conducting beak. Anatomical structure classification of medial malleolus at home and abroad is reported rarely. Hence, this morphological study is mainly designed to investigate the anatomical morphological classification and clinical significance of medial malleolus based on computed tomography (CT) three-dimensional reconstruction.

MATERIALS AND METHODS

From October 2018 to January 2021, 373 patients who underwent CT examination of malleolus medialis joint in the Jiang'an Hospital of Traditional Chinese Medicine were observed. The medial malleolus was observed and classified; then, geometric parameters were measured according to different medial malleolus types.

RESULTS

According to the results of 373 cases, medial malleolus can be divided into four types: omega type (66%), radical sign type (16%), inverted triangle type (14%), and wave type (4%).

CONCLUSIONS

There are four main shapes: omega, inverted triangle, radical sign, and wave in the medial malleolus of all normal ankles. The measurement of medial malleolus parameters according to medial malleolus in different shapes was of importance to guide smooth operation of medial malleolus fixation and deltoid ligament reconstruction and epidemiological.

57 A Closed Loop Audit of Post-Operative Driving Advice Documentation

Aim

The Driving and Vehicle Licensing Agency state post-operatively it is between the patient and doctor to establish when would be safe to resume driving, providing recovery does not exceed three months. This audit aimed to assess and improve the documentation rate of driving advice in the discharge summaries given to patients post abdominal surgery.

Method

Retrospective data collection from electronic records over the months of August and September 2020. 132 discharge summaries were screened to assess the baseline rate of verbal/documented driving advice given on discharge. Following the 1st cycle, posters encouraging the inclusion of driving advice and demonstrating how to access driving advice to discharge summaries were developed and distributed across the surgical wards. A 2nd cycle re-audit was conducted in October 2020 to measure the effect of change, and a further 3rd cycle audit was conducted in November 2020.

Results

1st cycle included 132 patients. 62% had documented advice on their discharge summaries, while 38% had no proof of driving advice. After intervention, 2nd cycle included 30 patients. Results showed a significant increase in advice documentation (80%). A 3rd cycle was carried out with 47 patients. This showed a reduction in advice documentation (66%).

Conclusions

Driving advice on discharge in post-operative patients is crucial part of patient safety. Implementation of intervention has increased the documentation of driving advice showing enhancing patient safety. However, 3rd cycle after registrar’s changeover showed a decrease in the rate of documentation. A teaching session is planned for new doctors followed by 4th cycle.

[Evaluation of classification of petroclival meningiomas and proposed selection of microsurgical approach: a single center experience of 179 cases]

Objective: To evaluate the classification of petroclival meningiomas(PCM), proposed selection of microsurgical approach and therapeutic outcomes. Methods: Retrospectively analyzed clinical data of 179 cases of PCM from Department of Neurosurgery, Xiangya Hospital, Central South University between January 2011 and November 2020. There were 28 males and 151 females with an age of(49.9±10.2) years(range: 22 to 75 years) and the tumor size of(44.8±10.3)mm(range: 15 to 80 mm). The mean duration of symptom(M(QR)) was 18.0(40.6)months(range:1 week to 320 months) and the mean preoperative Karnofsky performance scale(KPS) was 78.6±13.3(range: 40 to 100). The PCM were classified into 5 types according to the difference in the origin of dural attachment, involvement of adjacent structures and growth patterns through preoperative MRI. The surgical approaches were selected based on the proposed classification, and the clinical characteristics, surgical record, and follow-up data of each type were reviewed. Results: The PCM were divided into clivus type(CV, 4 cases), petroclival type(PC, 60 cases), petroclivosphenoidal type(PC-S, 62 cases), sphenopetroclival type with 2 subtypes(S-PC, 50 cases) and central skull base type(CSB, 3 cases). All of 176 cases were obtained microsurgical treatment except CSB type. The gross total resection reached in 124 cases(70.5%) with 112 cases of retrosigmoid approach(RSA), 27 cases of subtemporal transtentorial transpetrosal approach, 13 cases of pretemporal trancavernous anterior transpetrosal approach(PTCA), 12 cases of extended pterional transtentorial approach(EPTA) and presigmoid combined supra-infratentorial approach, respectively. The RSA could be adopted in both of CV type and PC type and most of PC-S type(71.0%). S-PC subtype Ⅰ and subtype Ⅱ were mainly underwent EPTA(40.8%) and PTCA(52.2%), respectively. Seventy-two cases(40.9%) gained new neurological dysfunctions mainly with the cranial nerve paralysis. The postoperative morbidity and complications were recovered or improved with conservative and positive symptomatic and supportive treatment. There was no intraoperative and postoperative death case. One hundred and sixty four cases(93.2%) of operative patients were followed with the duration of 24(48)months(range:3 to 108 months). Tumor recurrence and progress were identified in 14 cases(10.4%) and 14 cases(28.6%), respectively. Compared with postoperative neurological status, 89 patients(54.3%) had improved and 38 patients(23.2%) were still suffering various degrees of neurological dysfunctions during the follow-up. The recent KPS was 84.2±11.4(range: 50 to 100) without statistical difference from preoperative KPS(t=-1.356,P=0.125). As for each type, there were statistically significant differences in brain stem edema(χ2=3.482,P=0.038), gross total resection(χ2=9.127,P=0.001), surgical duration(F=8.954, P=0.013), postoperative length of stay(F=3.652, P=0.025), postoperative complications(χ2=1.550,P=0.024), postoperative KPS(F=2.856, P=0.042) and tumor recurrence/progress(χ2=4.824,P=0.013). Conclusion: The precise and comprehensive classification of PCM and specific individual treatment strategy are benefit to evaluate the diverse clinical prognosis, choose optimal surgical approaches, elevate gross total resection, diminish neurological dysfunctions and restraint tumor recurrence, so as to improve the quality of life for patients.

[Relapse of ankylosing spondylitis and its predictors after withdrawal of tumor necrosis factor-α inhibitors: a 52-week follow-up study]

OBJECTIVE

To investigate the recurrence of ankylosing spondylitis (AS) that has been relieved by standard-dose adalimumab (ADA) after dose reduction or withdrawal of tumor necrosis factor-α inhibitor (TNFi) and explore the factors that predict AS occurrence.

OBJECTIVE

This study was conducted among 63 patients with AS who reduced the dose of or discontinued TNFi after completing at least 12 treatment cycles with ADA (40 mg/2 weeks) to achieve ASAS20 improvement with a BATH disease activity index (BASDAI) < 4 for more than 8 weeks. The patients were followed up every 12 weeks for a total of 52 weeks, and the recurrence of AS, changes of BASDAI, C-reactive protein (CRP)-based disease activity score (ASDASCRP), low back pain (LBP) score, Bath Ankylosing Spondylitis Metrology Index (BASMI), CRP and ESR were recorded and analyzed. Cox regression model and ROC curve analyses were performed to analyze the risk factors of AS relapse after dose reduction or discontinuation of TNFi.

OBJECTIVE

Of the 63 patients enrolled, 57 completed the follow-up study, among whom 22 (38.6%) patients experienced AS relapse within 52 weeks, with a median clinical recurrence time of 31 weeks. The recurrence rate of AS was significantly higher in patients with complete withdrawal of medications (89.0%) than in those with TNFi dose reduction and TNFi discontinuation (P < 0.001), and did not differ significantly between the latter two groups of patients (χ²= 0.071, P=0.791). The Cox regression model showed that a high baseline LBP score (HR=1.438, P=0.027) and a high BASMI score (HR=1.29, P=0.049) were the risk factors for AS recurrence after TNFi dose reduction or discontinuation, while maintenance of medication during follow-up was a protective factor (HR=0.209, P=0.001). ROC curve analysis showed that the combination of baseline LBP score, BASMI and medication during follow-up had a good predictive value for AS relapse (AUC=0.819) with a sensitivity of 0.772 and a specificity of 0.718.

OBJECTIVE

Dose reduction or discontinuation of TNFi is associated with a high recurrence rate of AS that has been relieved by TNFi treatment. A high LBP score, a high BASMI score and discontinuation of maintenance medication are the risk factors for AS recurrence in patients after dose reduction or withdrawal of TNFi.

Effect modification of the association between diurnal temperature range and hospitalisations for ischaemic stroke by temperature in Hefei, China

OBJECTIVES

Diurnal temperature range (DTR) is an important indicator of global climate change. Many epidemiological studies have reported the associations between high DTR and human health. This study investigated the association between DTR and hospitalisations for ischaemic stroke in Hefei, China.

STUDY DESIGN

This is an ecological study.

METHODS

Data of daily hospital admissions for ischaemic stroke and meteorological variables from 1 January 2009 to 31 December 2017 were collected in Hefei, China. A generalised additive model combined with distributed lag non-linear model was used to quantify the effects of DTR on ischaemic stroke. The interactive effect between DTR and temperature was explored with a non-parametric bivariate response surface model.

RESULTS

High DTR was associated with hospitalisations for ischaemic stroke. The adverse effect of extremely high DTR (99th percentile [17.1 °C]) occurred after 8 days (relative risk [RR] = 1.021, 95% confidence interval [CI] = 1.002, 1.041) and the maximum effect appeared after 12 days (RR = 1.029, 95% CI = 1.011, 1.046). The overall trend of the effect of DTR on ischaemic stroke was decreasing. In addition, there was a significant interactive effect of high DTR and low temperature on ischaemic stroke.

CONCLUSIONS

This study suggests that the impact of high DTR should be considered when formulating targeted measures to prevent ischaemic stroke, especially for those days with high DTR and low mean temperature.

CNN-based qualitative detection of bone mineral density via diagnostic CT slices for osteoporosis screening

The features extracted from diagnostic computed tomography (CT) slices were used to qualitatively detect bone mineral density (BMD) through neural network models, and the evaluation results indicated that it may be a promising approach to perform osteoporosis screening in clinical practice.

INTRODUCTION

The purpose of this study is to design a novelty diagnostic method for osteoporosis screening by using the convolutional neural network (CNN), which can be incorporated into the procedure of routine CT diagnostic in medical examination thereby improving the osteoporosis diagnosis and reducing the patient burden.

METHODS

The proposed CNN-based method mainly comprises two functional modules to perform qualitative detection of BMD by analyzing the diagnostic 2D CT slice. The first functional module aims to locate and segment the ROI of diagnostic 2D CT slice, called Mark-Segmentation-Network (MS-Net). The second functional module is used to determine the category of BMD by the features of ROI, called BMD-Classification-Network (BMDC-Net). The diagnostic 2D CT slice of pedicle level in lumbar vertebrae (L1) was selected from 3D CT image in our experiments firstly. Then, the trained MS-Net can get the mark image of input original 2D CT slice, thereby obtain the segmentation image. Finally, the trained BMDC-Net can obtain the probability value of normal bone mass, low bone mass, and osteoporosis by inputting the segmentation image. On the basis of network results, the radiologists can provide preliminary qualitative diagnosis results of BMD.

RESULTS

Training of the network was performed on diagnostic 2D CT slices of 150 patients. The network was tested on 63 patients. Each patient corresponds to a 2D CT slice. The proposed MS-Net has an excellent segmentation precision on the shape preservation of different lumbar vertebra. The dice index (DI), pixel accuracy (PA), and intersection over union (IOU) of segmentation results are greater than 0.8. The proposed BMDC-Net achieved an accuracy of 76.65% and an area under the receiver operating characteristic curve of 0.9167.

CONCLUSIONS

This study proposed a novel method for qualitative detection of BMD via diagnostic CT slices and it has great potential in clinical applications for osteoporosis screening. The method can potentially reduce the manual burden to radiologists and diagnostic cost to patients.

Metabolic activation of retrorsine may disrupt bile acid homeostasis in mice through the Nrf2 pathway

BACKGROUND

The hepatotoxic pyrrolizidine alkaloids (PAs) were reported to increase bile acid (BA) levels in rat. However, it is still unclear whether the production of highly reactive dehydropyrrolizidine through CYP450s is directly relevant to BA changes.

OBJECTIVE

To further explore the mechanism by which metabolic activation of PAs induced BA changes, the effect of impaired or enhanced metabolic activation on the BA profiling and BA-related synthesis and transport genes were investigated and the involvement of Nrf2 pathway were explored.

METHODS

Blood and liver samples were collected after intragastrical administration of 35 mg/kg retrorsine or saline for seven days in wild-type (WT) and Nrf2 KO mice. CYP450 inhibitor, 1-aminobenzotriazole (ABT), or gamma-glutamylcysteine synthetase inhibitor, L-buthionine-sulfoximine (BSO) were employed in WT mice. Retrorsine-induced hepatotoxicity was evaluated by a biochemical method and H&E staining method. Serum BAs were quantified by high-performance liquid chromatography/triple quadrupole mass spectrometry. Blood pyrrole-protein adducts were semiquantified by high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. The gene and protein expression of BA-related transporters and enzymes in the liver were measured by a quantitative real-time PCR method and western blotting method.

RESULTS

The BA concentrations in serum were increased in the retrorsine-treated WT mice, along with the up-regulation of BA transporters, Ostβ, Mrp3, Mrp4, and Mrp2. When ABT was co-administered, the altered BA levels and Mrp4 mRNA and protein levels were reversed, accompanied by a 50% reduction of 6,7-dihydro-7-hydroxy-1- hydroxymethyl-5H-pyrrolizine (DHP) formation. When BSO was co-administered, serum BAs were not further increased but Ostβ, Mrp3, Mrp4 mRNA, and Mrp4 protein level continuously increased. The induction of Mrp4 by retrorsine among the tested BA transporters was the only one that was abolished or enhanced in the presence of ABT or BSO. The Nrf2 protein levels in the nucleus increased in the retrorsine-treated WT mice, which were remarkably repressed by co-administration of ABT and enhanced by co-administration of BSO. In Nrf2 KO mice receiving retrorsine, the bile acids and the mRNA and protein levels of Mrp2, Mrp3, Mrp4, and Ostβ were hardly changed, indicating the direct role of Nrf2 in retrorsine-induced BA changes in WT mice.

CONCLUSION

The activation of Nrf2 translocation by the formation of the reactive metabolite of PAs induced the expressions of BA transporters and changed serum BA levels. Mrp4 was a sensitive biomarker for the perturbation of redox status caused by the formation of dehydropyrrolizidine.

Dual Action of Acidic Microenvironment on the Enrichment of the Active Metabolite of Disulfiram in Tumor Tissues

Disulfiram, an antialcoholism drug, could potentially be repurposed as an anticancer drug because of the formation of copper(II) diethyldithiocarbamate (CuET) from dithiocarb (DTC, a reduced metabolite of disulfiram) and Cu²⁺ CuET exhibited preferential distribution to tumor tissues. This study investigated the mechanism of CuET accumulation in tumor tissues by employing MDA-MB-231 human breast cancer cells. The concentration of CuET in cells treated with DTC and Cu²⁺ in acidic culture medium (pH 6.8) was significantly higher than that of the control group (pH 7.4). Subsequently, the effects of pH on the uptake of DTC, Cu²⁺, and CuET were investigated separately. The acidic environment significantly increased the uptake rate of DTC and Cu²⁺ but had no effect on CuET. MDA-MB-231 cells overexpressing copper transporter hCTR1 were constructed to evaluate its intermediate role in CuET accumulation. After treatment with CuCl₂ followed by DTC for 15 minutes, the levels of CuET and Cu²⁺ in hCTR1-overexpressed cells were 2.5 times as much as those of vector group. In the tumors of cancer xenograft models constructed by hCTR1-MDA-MB-231 cells, the concentrations of CuET and Cu were also significantly higher than those of control group. In conclusion, the acidic microenvironment of tumors can promote the enrichment of CuET in tumors through dual action. On the one hand, it can promote transmembrane transport of DTC by converting ionic DTC into molecular state. On the other hand, it enhances Cu²⁺ uptake by activating hCTR1, which ultimately leads to the enrichment of CuET. SIGNIFICANCE STATEMENT: Increasing evidence suggests that the antitumor activity of disulfiram is related to the formation of a copper(II) diethyldithiocarbamate (CuET) of its reducing metabolite dithiocarb with copper(II) ion, which is preferentially distributed in tumor tissues. We showed that the acidic microenvironment, a common feature of many solid tumor tissues, could promote intracellular CuET accumulation through dual action without changing CuET uptake. This result is helpful for the formulation of clinical dosage regimens of disulfiram in cancer treatment.

CYP2C and CYP2B Mediated Metabolic Activation of Retrorsine in Cyp3a Knockout Mice

Background:

Retrorsine is one of the hepatotoxic pyrrolizidine alkaloids, which could be converted into a highly reactive metabolite, dehydroretrorsine, by CYP3A, and to a lesser extent by CYP2C and CYP2B.

Objective:

We employed Cyp3a knockout (3AKO) mice to investigate whether the absence of CYP3A could attenuate dehydroretrorsine formation and the role of CYP2C and CYP2B in the formation.

Methods:

Blood and liver samples were collected after intragastrical administration of 35 mg/kg retrorsine or saline for seven days in wild-type (WT) and 3AKO mice. Blood pyrrole-protein adducts were semi quantified by high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. The formations of glutathionyl-6,7-dihydro-1-hydroxymethyl-5H-pyrrolizine (GSH-DHP) and the activities of CYP3A, CYP2B and CYP2C were evaluated in the liver microsomes of WT and 3AKO mice before and after treatment. The metabolic phenotype of retrorsine was determined in human liver microsomes. The gene and protein expression of retrorsine metabolism-related CYP450s in the liver was measured by quantitative real-time PCR method and western blotting method. The serum cytokine level was detected by the ELISA method to reveal the potential mechanism of Cyp3a, Cyp2b and Cyp2c downregulation.

Results:

After an oral administration of 35 mg/kg retrorsine for seven days, the blood exposures of DHP adducts between WT and 3AKO mice were similar, consistent with the comparable formation of GSH-DHP in their liver microsomes. The chemical inhibitor experiment in liver microsomes indicated the predominant role of CYP3A and CYP2C in GSH-DHP formation in WT and 3AKO mice, respectively. Real-time qPCR analysis showed that the expressions of Cyp2b10 and Cyp2cs increased 2.3-161-fold in 3AKO mice, which was consistent with protein changes. The increased CYP2B activity in 3AKO mice supported the potential role of CYP2B in GSH-DHP formation. After a seven-day treatment of retrorsine, the yields of GSH-DHP were lower than the untreated ones in both alleles, accompanied by the decreased mRNA of Cyp3a, Cyp2b and Cyp2c. The increased serum IL6 might mediate the retrorsine-induced downregulation of Cyp450s.

Conclusion:

These data demonstrated the increased transcription of Cyp2c and Cyp2b caused by Cyp3a ablation, which played a vital role in the metabolic activation of retrorsine, and long-term exposure of retrorsine can reduce the CYP450 activities.