2021年 · 第134卷第04期

The open reduction and internal fixation (ORIF) was a standard treatment approach for fracture at distal humerus intercondylar, whereas the optimal way before ORIF remains inconclusive. We, therefore, performed a systematic review and meta-analysis to assess the efficacy and safety of olecranon osteotomy vs. triceps-sparing approach for patients with distal humerus intercondylar fracture.

The electronic searches were systematically performed in PubMed, EmBase, Cochrane library, and Chinese National Knowledge Infrastructure from initial inception till December 2019. The primary endpoint was the incidence of excellent/good elbow function, and the secondary endpoints included Mayo elbow performance score, duration of operation, blood loss, and complications.

Nine studies involving a total of 637 patients were selected for meta-analysis. There were no significant differences between olecranon osteotomy and triceps-sparing approach for the incidence of excellent/good elbow function (odds ratio [OR]: 1.37; 95% confidence interval [CI]: 0.69-2.75; P = 0.371), Mayo elbow performance score (weight mean difference [WMD]: 0.17; 95% CI:-2.56 to 2.89; P = 0.904), duration of operation (WMD: 4.04; 95% CI: -28.60 to 36.69; P = 0.808), blood loss (WMD: 33.61; 95% CI: -18.35 to 85.58; P = 0.205), and complications (OR: 1.93; 95% CI: 0.49-7.60; P = 0.349). Sensitivity analyses found olecranon osteotomy might be associated with higher incidence of excellent/good elbow function, longer duration of operation, greater blood loss, and higher incidence of complications as compared with triceps-sparing approach.

This study found olecranon osteotomy did not yield additional benefit on the incidence of excellent/good elbow function, while the duration of operation, blood loss, and complications in patients treated with olecranon osteotomy might be inferior than triceps-sparing approach.

Long non-coding RNAs (LncRNAs) comprise different types of RNA polymerase II-transcripted molecules, exhibit nucleotide lengths of greater than 200 nucleotides and do not undergo protein translation. Due to their characteristic feature of open reading frame, they have often been labelled as the "noise" of genomic transcription. Even though lncRNAs are widely transcribed genes, their expression level is lower than that of the protein-coding genes. Depending on their position relative to the protein-coding genes in the genome, lncRNAs are categorized as sense, antisense, bidirectional, intronic, and intergenic. Recently it has been shown that lncRNAs played important roles in both regulating cellular processes (cell differentiation and ontogeny) and disease development (pathogenic infection, immune destruction). Further, they have been implicated to be the hallmark of all cancers, the specific expression of lncRNA in tumor can be used to predict the prognosis and their stability in circulating body fluid (plasma and urine) provide a new basis for the development of cancer diagnosis and treatment. As lncRNAs act as a signal, decoy, guide, and scaffold molecule to regulate gene expression both transcriptionally and post-transcriptionally, elucidation of its function and the underlying regulatory mechanisms is of great significance for the advancement of life science research [Figure 1A].

Cardiovascular diseases continue to be the foremost cause of death among both males and females worldwide.^[1]Coronary artery disease (CAD) represents a major subtype of cardiovascular diseases. Recent evidence has highlighted a worldwide increase in incidence of CAD clinical manifestations regardless of geographical region.^[2]Despite a steady decline in CAD mortality in western countries over the past few decades, approximately one-third of the population suffering from CAD will succumb to the disease. Rapid and accurate diagnostic decisions are crucial for patients with CAD and aid in guidance for effective treatment.^[2]However, various factors may make the process of accurate CAD diagnosis a complex task.

Fibroblast growth factor 23 (FGF23) is a vital osteocyte-derived hormone that regulates the metabolism of phosphorus and 1, 25-dihydroxyvitamin D (1,25[OH]₂D). 1,25(OH)₂D and high dietary intake of phosphate up-regulate FGF23 expression, leading to increased renal phosphate excretion and decreased 1,25(OH)₂D synthesis, and then suppression of FGF23, thus completing a negative feedback loop. Several clinical studies of patients with kidney disease reported that an increased serum FGF23 level was associated with poor outcomes [Figure 1].^[1,2]

Statins are 3-hydroxy-3-methyl glutaryl (HMG)-coenzyme A (CoA) reductase inhibitors, acting on the rate-limiting enzyme for the conversion of HMG-CoA to L-mevalonate to reduce cholesterol biosynthesis. Apart from reducing cardiovascular events by lowering low-density lipoprotein cholesterol concentrations, pleiotropic cholesterol-independent functions of statins, including immunomodulatory and anti-inflammatory effects, are increasingly recognized. The current coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2),^[1]has caused >500,000 deaths worldwide as of July 2, and it continues to spread without specific antiviral therapies. Statins, with potential antiviral functions as a host-directed therapy (HDT), could be a safe means of improving outcomes for patients with COVID-19.^[2,3]

Microvascular decompression (MVD) has been widely accepted as the most effective remedy for hyperactive cranial rhizopathy, such as hemifacial spasm and trigeminal neuralgia.^[1,2]With popularization of this surgery around the world, numerous neurosurgeons have pre-sented their opinions concerning operative skills. For instance, some authors stated that the point of this process is to detach rather than to isolate the neurovascular confliction with Teflon insertion between them.^[3]It has been believed that "transposition" is better than "interposition" .^[4]In order to achieve an utter separation, "sling technique" has been frequently reported nowadays.^[5]Regardless of varied techniques, however, we should always put safety first while performing this functional neurosurgery. It is imaginable that the more complicated technique is employed, the more instruments or foreign bodies invade the surgical field, the more time elapses, and the more chances of postoperative complications incur eventually. Actually, this MVD operation could have been completed in a more easy and simple fashion. After accomplishment of more than 10,000 MVDs in our center,^[6,7]we have learned to go through the operation with minimal procedures in less time. In this paper, the author advanced a strategy of "three noes" for a safe and effective MVD.

The ongoing coronavirus disease 2019 (COVID-19) pandemic has resulted in considerable morbidity and mortality worldwide. Furthermore, the number of infected individuals is rising rapidly. This disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) belonging to the β-coronavirus cluster; this cluster also comprises the viruses causing severe acute respiratory distress syndrome (SARS) and Middle East respiratory syndrome. Similar to SARS-coronavirus (CoV), SARS-CoV-2 exploits angiotensin-converting enzyme 2 (ACE2) to invade its target cells; however, SARS-CoV-2 has a higher binding affinity for ACE2. Therefore, unlike SARS-CoV, which can be efficiently contained, SARS-CoV-2 is more infectious and difficult to control.

The current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant lesions. In China, breast masses are divided into four categories according to the treatment method: inflammatory masses, adenosis, benign tumors, and malignant tumors. These categorizations are important for guiding clinical treatment. In this study, we aimed to develop a convolutional neural network (CNN) for classification of these four breast mass types using ultrasound (US) images.

Taking breast biopsy or pathological examinations as the reference standard, CNNs were used to establish models for the four-way classification of 3623 breast cancer patients from 13 centers. The patients were randomly divided into training and test groups (n = 1810 vs. n = 1813). Separate models were created for two-dimensional (2D) images only, 2D and color Doppler flow imaging (2D-CDFI), and 2D-CDFI and pulsed wave Doppler (2D-CDFI-PW) images. The performance of these three models was compared using sensitivity, specificity, area under receiver operating characteristic curve (AUC), positive (PPV) and negative predictive values (NPV), positive (LR+) and negative likelihood ratios (LR-), and the performance of the 2D model was further compared between masses of different sizes with above statistical indicators, between images from different hospitals with AUC, and with the performance of 37 radiologists.

The accuracies of the 2D, 2D-CDFI, and 2D-CDFI-PW models on the test set were 87.9%, 89.2%, and 88.7%, respectively. The AUCs for classification of benign tumors, malignant tumors, inflammatory masses, and adenosis were 0.90, 0.91, 0.90, and 0.89, respectively (95% confidence intervals [CIs], 0.87-0.91, 0.89-0.92, 0.87-0.91, and 0.86-0.90). The 2D-CDFI model showed better accuracy (89.2%) on the test set than the 2D (87.9%) and 2D-CDFI-PW (88.7%) models. The 2D model showed accuracy of 81.7% on breast masses ≤1 cm and 82.3% on breast masses >1 cm; there was a significant difference between the two groups (P < 0.001). The accuracy of the CNN classifications for the test set (89.2%) was significantly higher than that of all the radiologists (30%).

The CNN may have high accuracy for classification of US images of breast masses and perform significantly better than human radiologists.

Chictr.org, ChiCTR1900021375; http://www.chictr.org.cn/showproj.aspx?proj=33139.

Previously, we developed a novel Coronary Artery Tree description and Lesion EvaluaTion (CatLet^©) angiographic scoring system, which was capable of accounting for the variability in the coronary anatomy and assisting in the risk-stratification of patients with acute myocardial infarction (AMI). Our preliminary study revealed that the CatLet score better predicted clinical outcomes for AMI patients than the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery score. However, the reproducibility of the CatLet score in both inter-and intra-observer remains to be evaluated.

A total of 30 consecutive AMI patients, admitted in September of 2015, were independently assessed by two experienced interventional cardiologists to evaluate the inter-observer reproducibility of the CatLet score. Another set of 49 consecutive AMI patients, admitted between September and October in 2014, were assessed by one of the two interventional cardiologists on two occasions 3 months apart to evaluate the intra-observer reproducibility of the CatLet score. The weighted kappa was used to express the degree of agreement.

The weighted kappa values (95% confidence interval) for the intra- and inter-observer reproducibility of the CatLet Score were 0.82 (0.59-1.00, Z= 7.23, P < 0.001) and 0.86 (0.54-1.00, Z= 5.20, P < 0.001), respectively, according to the tertile analysis (≤14, 15-22, >22). Regarding the adverse characteristics pertinent to lesions and dominance parameters, the kappa values for the inter-observer variability were 0.80 (0.56-1.00, Z = 6.47, P < 0.001) for total number of lesions, 0.57 (0.28-0.85, Z = 3.03, P < 0.001) for bifurcation, 0.69 (0.43-0.96, Z = 5.06, P < 0.001) for heavy calcification, 1.00 (0.72-1.00, Z= 6.93, P < 0.001) for tortuosity, 0.54 (0.26-0.82, Z = 3.78, P < 0.001) for thrombus, 0.69 (0.48-0.91, Z = 6.29, P < 0.001) for right coronary artery dominance, 0.69 (0.41-0.96, Z = 4.91, P < 0.001) for left anterior descending artery length, and 0.22 (0.06-0.51, Z = 1.56, P = 0.06) for diagonal size. Equivalent values for the intra-observer variability were moderate to almost perfect (range 0.54-1.00).

The reproducibility of the CatLet angiographic scoring system for evaluation of the coronary angiograms ranged from substantial to excellent. The high reproducibility of the CatLet angiographic scoring system will boost its clinical application to patients with AMI.

C-arm-based flat-panel detector cone-beam computed tomography (CBCT) venography has never been used in the management of iliac vein compression syndrome (IVCS). This study aimed to determine the technical feasibility and safety of CBCT venography in the diagnosis of IVCS compared with conventional venography (CV).

Twenty patients with clinical manifestations of lower extremity venous insufficiency were prospectively enrolled between May 2018 and December 2018. Each patient underwent both CV and CBCT venography. The feasibility and safety of CBCT venography were assessed by technical success rate and complication rate. The relationships between the clinical indexes and the results of CBCT venography and CV were analyzed with correlation analysis. The consistency of the diagnosis of IVCS using each modality was analyzed by the kappa test.

The technical success rate was 100% for CBCT venography and for CV, without any complications. Compared with CV, CBCT venography was able to show more details of adjacent tissues which might be helpful for making etiological diagnosis. The stenosis rate under CBCT venography had excellent consistency with that under CV (kappa= 0.78, Chi-square test). The stenosis rate under CBCT venography was positively correlated with the presence of collateral veins (odds ratio 1.12, 95% confidence interval: [1.00, 1.26], P= 0.049), while the stenosis rate under CV was not. Unexpectedly, only one patient had a venous pressure gradient of more than 2 mmHg (1 mmHg = 0.133 kPa).

For the diagnosis of IVCS, C-arm-based CBCT venography was technically feasible, with good safety. The presence of collateral veins on CBCT was clinically significant. A C-arm fluoroscopy-based technique that combines CV and CBCT might be a promising protocol for the management of IVCS during a single session.

Texture analysis (TA) can quantify intra-tumor heterogeneity using standard medical images. The present study aimed to assess the application of positron emission tomography (PET) TA in the differential diagnosis of gastric cancer and gastric lymphoma.

The pre-treatment PET images of 79 patients (45 gastric cancer, 34 gastric lymphoma) between January 2013 and February 2018 were retrospectively reviewed. Standard uptake values (SUVs), first-order texture features, and second-order texture features of the grey-level co-occurrence matrix (GLCM) were analyzed. The differences in features among different groups were analyzed by the two-way Mann-Whitney test, and receiver operating characteristic (ROC) analysis was used to estimate the diagnostic efficacy.

Inertia_GLCM was significantly lower in gastric cancer than that in gastric lymphoma (4975.61 vs. 11,425.30, z = -3.238, P = 0.001), and it was found to be the most discriminating texture feature in differentiating gastric lymphoma and gastric cancer. The area under the curve (AUC) of inertia_GLCM was higher than the AUCs of SUVmax and SUVmean (0.714 vs. 0.649 and 0.666, respectively). SUVmax and SUVmean were significantly lower in low-grade gastric lymphoma than those in high grade gastric lymphoma (3.30 vs. 11.80, 2.40 vs. 7.50, z = -2.792 and -3.007, P = 0.005 and 0.003, respectively). SUVs and first-order greylevel intensity features were not significantly different between low-grade gastric lymphoma and gastric cancer. Entropy_GLCM12 was significantly lower in low-grade gastric lymphoma than that in gastric cancer (6.95 vs. 9.14, z = -2.542, P = 0.011) and had an AUC of 0.770 in the ROC analysis of differentiating low-grade gastric lymphoma and gastric cancer.

Inertia_GLCM and entropy_GLCM were the most discriminating features in differentiating gastric lymphoma from gastric cancer and low-grade gastric lymphoma from gastric cancer, respectively. PET TA can improve the differential diagnosis of gastric neoplasms, especially in tumors with similar degrees of fluorodeoxyglucose uptake.

Estrogen is involved in the pathophysiological process of benign prostatic hyperplasia (BPH), in which epithelial-mesenchymal transition (EMT) plays an important role. Upregulation of aquaporin (AQP) 5, which is directly activated by estrogen, has been reported to promote EMT in multiple cells. This study aimed to examine the effects of AQP5 on estrogen-induced EMT in the prostate.

Normal prostate (NP) tissue samples without any histopathological changes and BPH tissue samples with pathologically confirmed hyperplasia were obtained. An EMT cell model was subsequently established by adding estradiol (E2) to RWPE-1 cells, after which AQP5 knockdown was performed. Tissue morphological and immunohistochemical features were examined using hematoxylin-eosin and immunohistochemical staining. Western blot analysis was performed to determine the expression of AQPs, estrogen receptors, and EMT-related proteins. Cell proliferation was assessed and supernatants were collected for enzyme-linked immunosorbent assay to determine transforming growth factor-β1 (TGF-β1) concentrations. Immunofluorescence staining was performed to assess protein expressions in RWPE-1 cells.

BPH tissues exhibited greater EMT (TGF-β1: 1.362 ± 0.196 vs. 0.107 ± 0.067, P = 0.003; vimentin: 1.581 ± 0.508 vs. 0.221 ± 0.047, P < 0.001; E-cadherin: 0.197 ± 0.188 vs. 1.344 ± 0.088, P < 0.001), higher AQP5 (1.268 ± 0.136 vs. 0.227 ± 0.055, P < 0.001) and estrogen receptor (ER) α (1.250 ± 0.117 vs. 0.329 ± 0.134, P < 0.001) expression but lower ERβ (0.271 ± 0.184 vs. 1.564 ± 0.130, P < 0.001) expression than NP tissues. E2-stimulated cells had higher AQP5 expression (1.298 ± 0.058 vs. 1.085 ± 0.104, P = 0.049), increased cell proliferation (1.510 ± 0.089 vs.1.000 ± 0.038, P < 0.001), and EMT (TGF-β1 concentration: 0.352 ± 0.021 ng/mL vs. 0.125 ± 0.014 ng/mL, P < 0.001; vimentin: 1.641 ± 0.120 vs. 0.188 ± 0.020, P = 0.002; E-cadherin: 0.075 ± 0.030 vs. 0.843 ± 0.046, P < 0.001) than controls. E2-stimulated cells with AQP5 knockdown exhibited decreased EMT (TGF-β1 concentration: 0.223 ± 0.041 ng/mL vs. 0.352 ± 0.021 ng/mL, P= 0.016; vimentin: 0.675 ± 0.056 vs. 1.641 ± 0.120, P = 0.001; E-cadherin: 0.159 ± 0.037 vs. 0.075 ± 0.030, P = 0.040) than E2-stimulated cells with non-related small interfering RNA (siRNA).

Our findings suggest that estrogen induces BPH possibly by promoting AQP5 expression. Hence, AQP5 might be a novel target for modulating EMT in prostate epithelial cells.

Hyperthermia in combination with DnaJA4-knockout (KO) obviously affects the anti-viral immunity of HaCaT cells. The mechanisms of this process are not yet fully explored. However, it is known that DnaJA4 interacts with actin cytoskeleton after hyperthermia. Our aim was to investigate the effects of DnaJA4 on F-actin in HaCaT cells following hyperthermia.

Wild-type (WT) and DnaJA4-KO HaCaT cells were isolated at either 37°C (unheated) or 44°C (hyperthermia) for 30 min followed by testing under conditions of 37°C and assessing at 6, 12, and 24 h after hyperthermia. The cytoskeleton was observed with immunofluorescence. Flow cytometry and Western blotting were used to detect the expression of F-actin and relevant pathway protein.

DnaJA4-KO and hyperthermia changed the cytoskeleton morphology of HaCaT cells. F-actin expression levels were elevated in DnaJA4-KO cells compared with WT cells (6364.33 ± 989.10 vs. 4272.67 ± 918.50, P < 0.05). In response to hyperthermia, F-actin expression levels of both WT and DnaJA4-KO cells showed a tendency to decrease followed by an obvious recovery after hyperthermia (WT cells: unheated vs. 6 h after hyperthermia or 24 h after hyperthermia: 0.34 ± 0.02 vs. 0.24 ± 0.01, 0.31 ± 0.01, P < 0.001, P < 0.05; DnaJA4-KO cells: unheated vs. 6 h after hyperthermia or 24 h after hyperthermia: 0.44 ± 0.01 vs. 0.30 ± 0.01, 0.51 ± 0.02, P < 0.001, P < 0.01). WT cells restored to baseline levels observed in the unheated condition, while DnaJA4-KO cells exceeded baseline levels in the recovery. As the upstream factors of F-actin, a similar profile in rho-associated serine/threonine kinase 1 (ROCK 1) and RhoA expressions was observed after hyperthermia. While E-cadherin expression was decreased in response to hyperthermia, it was increased in DnaJA4-KO cells compared with WT cells.

Hyperthermia affects the expression levels of F-actin in HaCaT cells. DnaJA4 knockout increases the expression of F-actin in HaCaT cells after hyperthermia. DnaJA4 regulates the expressions of F-actin and the related pathway proteins in response to hyperthermia in HaCaT cells.

Vasovagal syncope (VVS) greatly impairs quality of life. The therapeutic efficacy of oral rehydration saline (ORS) for unselected VVS patients is not satisfactory due to the diverse mechanisms of the disease. Body mass index (BMI) was demonstrated to reflect blood volume to a certain extent. Therefore, the present study explored the capability of BMI to predict the therapeutic response of children with VVS to ORS treatment.

Seventy-four children with VVS who visited the Syncope Unit of Pediatrics at Peking University First Hospital from November 2010 to June 2019 receiving ORS treatment were enrolled for this retrospective case-control study. A comparison of demographic, clinical, and hemodynamic characteristics was performed between responders and non-responders. The correlation between baseline BMI and response time was analyzed. To determine the value of baseline BMI in predicting the therapeutic efficacy of ORS in children with VVS, a receiver operating characteristic curve analysis was performed.

Fifty-two children were identified as responders, and the remaining 22 children were identified as non-responders. The baseline BMI of the responders was much lower than that of the non-responders (16.4 [15.5, 17.8] kg/m²vs. 20.7 ± 3.6 kg/m², P < 0.001), and baseline BMI was positively correlated with response time in the head-up tilt test after adjusting for sex (r = 0.256, 95% confidence interval [CI]: 0.067-0.439, P = 0.029). The area under the receiver operating characteristic curve of baseline BMI was 0.818 (95% CI: 0.704-0.932, P < 0.001), and an optimal cut-off value of 18.9 kg/m² yielded a sensitivity of 83% and a specificity of 73% to predict the efficacy of ORS in VVS.

Prior to treatment, baseline BMI is a promising predictor of response to ORS in children with VVS.

Iodine extravasation is commonly seen in stroke patients after successful mechanical thrombectomy. Iodine extravasation may be associated with patient prognosis, and more iodine extravasation is highly associated with the development of severe hemorrhagic transformation (HT). Hence, it is essential to identify early hemorrhage after intra-artery therapy and the imaging indicators that can predict late hemorrhage transformation. Several studies have used different quantitative and non-quantitative methods to evaluate iodine extravasation. However, they concluded with different results.^[1,2,3]The aim of our study was to propose two easy and practical semiquantitative methods to evaluate iodine extravasation and their relation to hemorrhage transformation.

Heart failure (HF) is a worldwide problem due to the substantial morbidity and mortality of patients with cardiovascular diseases. Recently, the PARADIGM-HF trial (the Prospective comparison of angiotensin receptor-neprilysin inhibitor [ARNI] with angiotensin-converting enzyme inhibitor [ACEI] to Determine Impact on Global Mortality and morbidity in Heart Failure trial) showed that ischemic heart disease is the most common etiology of HF, which accounts for 60% of HF with reduced ejection fraction (HFrEF).^[1]However, effective predictors are still in urgent need to predict ischemic cardiomyopathy (ICM) in HF patients.

Detection of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a supplemental option for reverse transcription polymerase chain reaction (RT-PCR) detection, regardless of whether it is immunoglobulin M (IgM), immunoglobulin G (IgG) or combined detection. However, there are inadequate data on the sensitivity and specificity of IgM/IgG detection, which is of paramount importance for the decision of whether, when, and how to use IgM/IgG antibody detection. The aim of this study was to evaluate the sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of IgM/IgG antibody detection, especially the anti-interference ability and kappa coefficient compared with the SARS-CoV-2 RT-PCR, which was defined as a standard diagnosis in this study.

Cervical spondylosis refers to degenerative changes in the sub-axial cervical spine. Symptoms caused by spondylosis include axial neck pain, cervical radiculopathy, and cervical myelopathy. One of the most commonly used surgical treatments is anterior cervical discectomy and fusion (ACDF); it is reported that ACDF leads to the development of progressive adjacent segment degeneration (ASD) in over 90% of the patients with up to 25.6% requiring reoperations due to symptomatic ASD.^[1]Recent total disc replacement (TDR) prostheses were developed to restore motion capability of the diseased-levels, but clinical outcomes and post-operative re-operation rates were not superior to ACDF.^[2]As the etiology of ASD is unclearly defined, a possible explanation for ASD is that the spinal motion restored after ACDF or TDR does not match thein vivophysiological motion of the patient-specific cervical spine.^[1]Since noin vivodata has previously been reported on the cervical motions of symptomatic patients, we evaluated thein vivorange of motion (ROM) of each sub-axial cervical segment in spondylotic patients with the symptom at C5-6 using a dynamic imaging technique, and compared the patients’ data with those of an asymptomatic control group of matched age and sex distributions. We specifically investigated whether and how spondylosis affects cervical motion before surgical interventions. This research was approved by the Partners Human Research Committee at Massachusetts General Hospital (No. 2012P002508/MGH).

To the Editor:Ischemic coronary artery disease is the leading cause of heart failure (HF) which is a major public health burden worldwide. Over the past decades, development of new pharmacological therapies and implementation of early reperfusion strategies have contributed to a significant reduction in mortality associated with acute myocardial infarction (AMI). However, improved survival in acute cardiac ischemic event has expanded the pool of patients prone to cardiac remodeling and adverse cardiovascular (CV) outcomes.

To the Editor:Revascularization after chronic coronary total occlusion (CTO) can relieve symptoms of angina and improve both cardiac function and clinical prognosis.^[1,2]However, percutaneous coronary intervention (PCI) for revascularization of CTO lesions is challenging because of a high incidence of complications and long X-ray exposure time. While the success rate for PCI in CTO has significantly increased in recent years due to the emergence of new technologies, devices and anticoagulation strategies,^[3,4]these new devices have also led to complications such as coronary artery perforation and cardiac tamponade, which limit their application. As routine PCI procedures for CTO intuitively require operationally safe devices, we have developed a new device called the real-time intravascular ultrasound (IVUS) double-lumen microcatheter (RLS catheter). Here, we briefly describe the RLS catheter, report our experience with this device, and provide data on its efficacy and safety in CTO revascularization.

To the Editor:A 68-year-old man presented with a 2-month aphasia. Magnetic resonance imaging scan revealed an abnormal signal in the left temporal lobe with heterogenous enhancement [Figure 1A]. Glioma was considered, and the patient underwent total tumor resection. Microscopic examination of the resected tumor showed a high-grade glial tumor with pleomorphic cells, elevated mitotic activity, microvascular proliferation, and pseudopalisading necrosis [Figure 1BandFigure 1C]. Part of the lesion contained round cells with perinuclear halos. Tumor cells also grew around neurons, forming secondary structures [Figure 1D]. On immunohistochemical investigation, the tumor cells expressed glial fibrillary acidic protein and oligodendrocyte transcription factor 2 [Figure 1E]. There was only focal positivity for p53 protein (about 5% of tumor cells), while alpha-thalasse-mia/mental retardation syndrome X-linked protein expression was positive. The tumor cells were negative for isocitrate dehydrogenase 1 (IDH1) R132H, NeuN, and H3 K27M. The Ki-67 index was approximately 20%. Next-generation sequencing analysis (Simcere Diagnostics, Nanjing, China) was performed on the formalin-fixed paraffin-embedded tumor tissues. The results showed a heterozygous IDH1 CGT>AGT G131D mutation, epidermal growth factor receptor (EGFR) amplification, cyclin-dependent kinase inhibitors 2A/B (CDKN2A/B)deletion, loss of chromosome 10 as well as 1p loss of heterozygosity [Figure 1FandFigure 1G], while chromosome 19q was intact. Mutations ofIDH2, H3F3A, HIST1H3B, BRAF,andTERTpromoters were absent.IDH1G131D mutation was confirmed by sanger sequencing [Figure 1H]. The presence of 1p /19q [Figure 1IandFigure 1J] andEGFRamplification [Figure 1K] was confirmed via fluorescencein situhybridization (Guangzhou LBP Pharmaceutical Technology Co. Ltd, China). The tumor was finally diagnosed as glioblastoma,IDH-mutant (IDH1G131D mutation), World Health Organization grade IV. Post-operatively, the patient received combination of radiotherapy and chemotherapy (temozolomide, 140 mg, qd). No recurrence or progression was observed from a follow-up of 2 months. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee (No. [2019]004) and with the 1964Helsinki Declarationand its later amendments or comparable ethical standards. The authors have obtained the appropriate patient’s consent form.

To the Editor:In the era of evidence-based medicine, the traditional randomized controlled trials (RCT) is on the top of the pyramid of evidence hierarchy. With well-controlled inclusion and exclusion criteria, randomization, and strict intervention protocol, traditional RCT construct the ideal medical circumstance, under which the causal relationship between the outcome and intervention can be better interpreted. However, it will also make the external validity and generalizability of traditional RCT limited.^[1,2]Real-world study (RWS) refers to research that analyzes real-world data, including registries, databases, electronic health records, claims or insurance databases, and other health data outside the traditional controlled trial settings.^[3]Comparative effectiveness research (CER), the counterpart of traditional RCT in RWS, refers to the studies comparing the effectiveness and safety of an intervention in real-world clinical settings. CER, composed of observational studies and pragmatic RCT, has become a promising source of evidence that complements traditional RCT.^[4]Unlike traditional RCT, pragmatic RCT attempts to perform trials in real-world clinical settings to extend the generalizability of RCT.^[5]

To the Editor:Bronchiectasis is a chronic respiratory disorder characterized by recurrent cough, sputum production, and respiratory infections. Management of bronchiectasis has got an increased emphasis in recent years.^[1]Patients with bronchiectasis should undergo routine monitoring in order to identify disease progression and modify treatment when necessary. In recent years, three composite disease-specific systems have been developed, which are verified for evaluating bronchiectasis severity and predicting prognosis: bronchiectasis severity index (BSI), FACED (F: forced expiratory volume in 1 s % predicted [FEV1%pred], A: age, C: presence of chronic colonisation byPseudomonas aeruginosa, E: radiological extension[number of pulmonary lobes affected], D: dyspnoea) and FACED plus exacerbations in the previous year (E-FACED).^[2,3,4]All three scoring systems classify patients into low, moderate, and high risk groups by different thresholds, respectively. Study shows that BSI can better predict mortality, exacerbations, quality of life, respiratory symptoms, 6-min walk distance, and lung function decline in bronchiectasis. Updated in 2019, British Thoracic Society (BTS) guideline for bronchiectasis in adults emphasizes that the use of BSI and FACED scoring systems has increased ability to predict future morality in patients with bronchiectasis, as well as assisting in guiding the disease management.^[4]However, literature about these systems in predicting hospital readmission in patients with bronchiectasis is still limited. This study evaluated the prediction ability of BSI, FACED, and E-FACED on assessing the readmission risk of bronchiectasis patients, as well as making comparison of the prediction ability among the three systems.

To the Editor:The Human Genome Project decodes the mysteries of life, explores the pathogenesis of disease, and provides scientific evidence for the diagnosis and treatment of disease. Traditional sequencing methods predominantly provide genome-wide sequence information and an average of the mix of cell types, which does not take into account the heterogeneity between cells and between subtypes. Advances in genome sequencing technology have allowed the development of single cell sequencing (SCS).

To the Editor: Pediatric lung transplantation is a highly specialized therapy for end stage pulmonary disease in children, and is performed in only a handful of transplant centers around the world. In the past decade, about 100 cases of pediatric lung transplantation have been performed annually all over the world. Most centers perform 1 to 4 pediatric lung transplantations annually, with only five centers performing more than five per year. Since 2007, our team has performed lung transplantations in 12 pediatric patients, among whom 11 were over 10 years old.

To the Editor: Placenta previa is one of the main causes of bleeding in late pregnancy and childbirth. According to the relationship between the lower edge of the placenta and the internal cervix, placenta previa can be classified as incomplete placenta previa (IPP) and complete placenta previa (CPP). IPP indicates that the lower edge of the placenta reaches but does not exceed the internal cervix. CPP refers the lower edge of the placenta covering and exceeding the internal cervix. This common classification standard is applicable to cases in which the myometrium is intact and only the placenta is prepositioned. However, when a pregnant woman who has previously delivered by cesarean section presents with placenta previa in the current pregnancy, and the placenta is attached to the uterine scar, there are significant increases in the risks for post-delivery bleeding and various complications. These cases have been given a new name, pernicious placenta previa (PPP).^[1]

To the Editor: Collodion baby is a descriptive term for an extremely rare congenital condition characterized by the presence of parchment-like or cellophane-like membranes encompassing the whole body at birth.^[1,2]The membrane usually peels off after several weeks, and the infant displays one of several ichthyosis skin types. Many complications, such as ectropion, eclabium, and restricted joint move-ments, are frequently seen in collodion babies due to the tight skin.^[1,2]Cases have been occasionally reported about the systemic and conservative treatment management of ectropion.^[3]However, there have been few reports of surgical management of the striking edematous conjunctiva due to ectropion in collodion baby.