Objective:To analyze the clinical characteristics, imaging, myopathology and outcomes of patients with COVID-19 related autoimmune myopathy.Methods:The clinical features, serum creatine kinase (CK), myositis antibodies, muscle magnetic resonance imaging, myopathology and therapy of 5 patients with COVID-19 related autoimmune myopathy diagnosed in Peking University First Hospital from December 2022 to April 2023 were collected. The effects of the therapy after a short term follow up were analyzed.Results:Among the 5 patients, there were 3 males and 2 females, with onset age of 42-86 years. All patients presented with proximal muscle weakness in the recovery term of COVID-19. Myalgia was noted in 3 cases, dysphagia in 1, skin damage in 2, interstitial lung disease in 1. The serum CK of the 5 patients was 1 663-16 000 IU/L, 1 patient had anti-3-hydroxy-3-methylglutaryl-CoA reductase autoantibodies and 1 patient had anti-signal recognition particle autoantibodies. The electromyography showed myogenic lesions in all patients. Muscle magnetic resonance imaging showed diffuse muscle edema in all patients, myofascial edema in 3 and subcutaneous-tissue edema in 3. The muscle biopsies in 4 patients revealed necrotic myopathy,with high P62 expression in muscle fibers. The electromicroscopy of 2 patients revealed vacuolated mitochondria and intranuclear tubulofilamentous inclusions in muscle fibers. Four patients were treated with glucocorticoids, of whom 2 patients combined with intravenous immunoglobulin, tacrolimus or cyclophosphamide. One case had close monitoring without drug therapy. They showed significant improvement, but the CK was still abnormal in 4 patients.Conclusions:COVID-19 leads to immune mediated myopathy. The manifestation of patients is characterized by proximal predominant weakness and high creatine kinase level. Muscle magnetic resonance imaging shows diffuse muscle edema. The muscle biopsies reveal necrotic myopathy. The effectiveness of immunosuppression needs to be further studied.

Objective:To study positive rates and typing of oligoclonal bands (OCB) in patients with neurological disorders, and to reveal the clinical significance and applicational value of OCB test.Methods:A retrospective analysis was performed on the detection results of 3 217 patients with neurological disorders who undertook both serum and cerebrospinal fluid OCBs in the First Hospital of Peking University from January 2012 to August 2022. According to the final diagnosis, the patients were divided into 13 groups including multiple sclerosis (479 cases), neuromyelitis optica spectrum disorders (935 cases), autoimmune encephalitis (192 cases), viral encephalitis (94 cases), nervous system complication after HSCT (232 cases), Guillain-Barré syndrome (644 cases), chronic inflammatory demyelinating polyneuropathy (157 cases), etc. Cerebrospinal fluid and serum OCBs were detected using isoelectric focusing electrophoresis combining immunofixation, then classified into Ⅰ-Ⅴ types according to the morphology. Consequently, positive rates and types were analyzed for each group. χ2 test was used for comparison between groups. Results:The positive rates of cerebrospinal fluid OCB in multiple sclerosis, nervous system complication after hematopoietic stem cell transplantation (HSCT), autoimmune encephalitis, viral encephalitis, neuromyelitis optica spectrum disorders, Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy were respectively 66.8% (320/479), 48.7% (113/232), 46.4%(89/192), 19.1% (18/94), 17.6% (165/935), 9.9% (64/644), 5.1% (8/157). For patients with multiple sclerosis, neuromyelitis optica spectrum disorders, viral encephalitis, and autoimmune encephalitis, Type Ⅱ bands took the majority of cerebrospinal fluid OCB-positive cases with the rates of 94.1% (301/320), 78.7% (70/89), 77.8% (14/18), and 77.6% (128/165) respectively, indicating intrathecal IgG synthesis; for patients with nervous system complication after HSCT, Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy, type Ⅳ bands took the majority of cerebrospinal fluid OCB-positive cases with the rates of 94.7% (107/113), 82.8% (53/64) and 100% (8/8), indicating no obvious intrathecal IgG synthesis. The positive rates of cerebrospinal fluid oligoclonal bands were significantly different among all groups (χ 2=1 268.31, P<0.001). Conclusion:The positive rates of cerebrospinal fluid oligoclonal bands are different among different neurological disorders, in which the positive rate of cerebrospinal fluid OCB is higher with type Ⅱ bands as the majority type in multiple sclerosis, which indicates that the detection and typing of cerebrospinal fluid OCB are helpful for the diagnosis of various neurological diseases, especially for multiple sclerosis.

Objective The study aims to optimize the conditions for constructing orthotopic nude mouse models of liver cancer by injecting human liver tumor cell lines and to explore appropriate timings for drug administration. Methods Human hepatocellular carcinoma Hep3B and hepatoblastoma HepG2 cell lines, which stably expressing the luciferase reporter gene (LUC), were selected. The linear correlation between the luciferase luminescence intensity and the number of liver tumor cells was analyzed using a Small Animal In Vivo Imaging system to verify the luminescent efficiency of the human liver tumor cells. Different concentrations (8×10⁶, 2.4×10⁷, 7.2×10⁷ cells/mL) and resuspension media (PBS, Matrigel) of human liver tumor cell suspensions HepG2-LUC and Hep3B-LUC were orthotopically inoculated into the liver lobes of 5-week-old female BALB/c nude mice (12 groups, 7 mice each) to construct human liver tumor nude mouse orthotopic cancer models. Every 7 days, the weights of mice were recorded, and the growth of orthotopic tumors was monitored using the Small Animal In Vivo Imaging system. On day 35 post-cell inoculation, mouse livers were dissected, and pathological slices were prepared for HE staining to observe histopathological changes in liver tissues. Results The luminescence intensity of human liver tumor cell lines was positively correlated with the number of cells (R²=0.983 1, R²=0.970 5), indicating their suitability for orthotopic model construction. Successful modeling was achieved in the high-concentration groups of HepG2-LUC, the low-, medium-, and high-concentration groups of HepG2-LUC+Matrigel, the medium- and high-concentration groups of Hep3B-LUC, and the low-, medium-, and high-concentration groups of Hep3B-LUC+Matrigel. For both HepG2-LUC+Matrigel and Hep3B-LUC+Matrigel groups, mice in the high-concentration groups exhibited significantly reduced body weight compared to the low- and medium-concentration groups (both with P<0.05). The luminescence intensity of successfully modeled mice increased exponentially over time (R²>0.950 0), and reached a minimum of 1.0×10⁷ p/(s·cm²·sr) by day 14 post-transplantation. Mice in the low- and medium-concentration groups of HepG2-LUC and the low-concentration group of Hep3B-LUC showed no significant pathological changes, while the other groups exhibited evident liver tumors and hepatocyte lesions. Conclusion For the HepG2-LUC cell line, the recommended injection volume is 50 µL with a cell density of 2.4×10⁷ cells/mL, resuspended with Matrigel, followed by drug administration or prognostic measures on day 7 post-modeling. For the Hep3B-LUC cell line, the recommended injection volume is 50 µL with a cell density of 7.2×10⁷ cells/mL, not resuspended with Matrigel, with administration or prognostic measures on day 14 post-modeling.

Objective To assess the tear film stability and morphological characteristics of the tarsal gland in myopic children.Methods In this prospective descriptive study,myopic children who performed refractive examinations in the Pediatric Ophthalmology & Refraction Clinic,Jinan Mingshui Eye Hospital from November 2021 to November 2022 were in-cluded.An Ocular Surface Disease Index(OSDI)questionnaire survey was carried out;tear meniscus height(TMH),non-invasive first breakup time(NIf-BUT)and images of the tarsal glands were obtained by OCULUS Keratograph 5M compre-hensive ocular surface analyzer.In addition,the atrophy and tortuosity of tarsal glands were scored to analyze the tear film stability and clinical characteristics of tarsal glands in myopic children.Results A total of 48 myopic children(91 eyes)aged from 7 to 16(10.25±2.23)years were recruited,including 27 males(56.25％)and 21 females(43.75％).The aver-age TMH was(0.19±0.04)mm(95％CI:0.18-0.19)and the average NIf-BUT was(5.40±2.62)s(95％CI:4.90-5.94);the TMH was positively correlated with NIf-BUT(r=0.223,P=0.034).The tarsal gland atrophy score was 1(0,1).The tortuosity score of the upper and lower tarsal gland was 0(0,1)and 0(0,0),respectively,with a statistically significant difference(Z=3.692,P＜0.001).In all subjects,49 eyes(53.85％)had tarsal gland atrophy,and 37 eyes(40.66％)had tarsal gland tortuosity.There were significant differences in TMH and NIf-BUT between children aged＜12 years and children aged ≥12 years(both P＜0.05).There was a significant difference in TMH between children with an OSDI score＜13 and children with an OSDI score ≥ 13(t=2.305,P=0.026).There was a significant difference in NIf-BUT between mild and moderate myopia children(t=2.300,P=0.024);the spherical equivalent was positively correlated with NIf-BUT(r=0.283,P=0.023).Conclusion Children with mild to moderate myopia show low tear film stability and a certain proportion of abnormal morphology in tarsal glands.In addition to the refractive status of children,attention should also be paid to ocular surface health in the refraction clinic.

Objective:To explore the diagnostic value of quantitative analysis of contrast-enhanced ultrasound for deep venous thrombosis of lower extremity after total hip arthroplasty.Methods:A total of 150 patients suspected of deep venous thrombosis of lower extremity undergoing total hip arthroplasty treatment in Jiaozhou Central Hospital of Qingdao from June 2021 to June 2022 were selected. Color Doppler ultrasound diagnostic instrument was used to examine the deep vein vessels of the lower limbs of patients, and quantitative analysis of contrast-enhanced ultrasound was performed to record the color Doppler detection results of patients. Quantitative parameters of contrast-enhanced ultrasound including time to peak (TIP), derived peak intensity (DPI), slope of ascending branch of curve (C) were compared between patients with deep vein thrombosis of lower extremities and normal patients. According to the onset time of symptoms of lower extremity thrombus group, patients were divided into acute stage, subacute stage and chronic stage, and the thrombus elasticity score and thrombus strain ratio among the three subgroups were compared.Results:Angiography results showed that 82 patients were diagnosed with deep vein thrombosis of lower extremities. The Kappa = 0.904, sensitivity was 95.00%, specificity was 91.43%, accuracy was 93.33%, positive prediction rate was 92.68%, and negative prediction rate was 94.12% by using contrast-enhanced ultrasonography and angiography in the diagnosis of deep vein thrombosis of lower extremity. The Kappa = 0.616, the sensitivity was 77.55%, specificity was 88.46%, accuracy was 81.33%, positive prediction rate was 92.68%, negative prediction rate was 67.65% by using ultrasonography and angiography in the diagnosis of deep venous thrombosis of lower extremities. The TIP level in patients with deep venous thrombosis of lower limbs was higher than that in normal patients, the DPI and C levels were lower than that in normal patients: (40.21 ± 12.34) s vs. (13.50 ± 4.59) s, (- 32.27 ± 7.56) dB vs. (- 11.33 ± 3.07) dB, (1.88 ± 0.40) dB/s vs. (4.75 ± 1.34) dB/s, there were statistical differences ( P<0.05). There were 28 cases of acute stage thrombosis, 22 cases of subacute stage thrombosis, and 32 cases of chronic stage thrombosis. There were statistically significant differences in thrombus elasticity score and thrombus strain ratio among patients with lower extremity thrombosis at different periods. Thrombus elasticity score and thrombus strain ratio of patients with acute stage thrombus were the lowest. Conclusions:Quantitative analysis of contrast-enhanced ultrasound has good consistency in the diagnosis of lower extremity deep vein thrombosis after total hip arthroplasty, and has certain clinical significance for staging diagnosis of lower extremity deep vein thrombosis.

Objective This study aimed to investigate the MRI features of forearm muscles from myotonic dystrophy type 1(DM1)and to evaluate the correlation between clinical factors and muscle MRI.Methods We retrospectively reviewed the medical records of genetic-confirmed DM1 patients including the clinical manifestations,the electromyography and the muscle pathology results.MRI scan was used to examine forearm muscles.Analysis of T1weighed images and short inversion time inversion recovery images were used to evaluate muscle fatty infiltration and muscle edema,respectively.The correlation between the fatty infiltration and age,disease duration and muscle strength were investigated.Results Twenty-three DM1 patients from different family were enrolled.The onset age was 17～60 year-old,mean age was(34.3±12.2)year-old,and the mean course of disease was 5(3,9)years.Their main symptoms were hand weakness and stiffness,accompanying with alopecia and excessive daytime sleepiness.The median fatty infiltration scores were recorded as follows:flexor digitorum profundus(FDP)4.0(3.0,4.0),flexor pollicis longus(FPL)4.0(3.0,4.0),extensor pollicis brevis 2.0(1.0,2.5),abductor pollicis longus 2.0(0.5,2.5),extensor pollicis longus 2.0(1.0,2.0),flexor digitorum superficialis 2.0(0.5,2.5),supinator(S)2.0(1.0,2.0).Other muscles scores were less than 1 of which the pronator teres(PT)was 1.0(0.0,1.0).Atrophy of FDP was detected in nine,atrophy of FPL in six and hypertrophy of PT in 11 patients.The muscle edema was evident in FDP,FPL,and the flexor digitorum superficialis,while brachioradialis and pronator teres were normal.There was no significant correlation between mean muscle fat infiltration score and age or course of disease.The mean muscle fat infiltration was significantly correlated with muscle strength score(r =-0.590,P<0.01).The mean fatty infiltration scores of FDP and FPL were not correlated with age nor course of disease,but correlated with grip strength(r =-0.754,P<0.01 and r =-0.699,P<0.01).Conclusion The forearm MRI in DM1 patients exhibit a relatively specific distribution of selective muscle involvement and can be used to assess muscle weakness.

Anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) myopathy is one of the subtypes of immune-mediated necrotizing myopathy. Anti-HMGCR antibodies induce complement activation,subsequently resulting in myofiber necrosis,regeneration with autophagy abnormalities and mitochondrial changes. The age of onset is from children to adulthood. Some patients have a history of exposure to statins. Most patients are subacute onset. The patients with chronic progressive process, are more like muscular dystrophy. The main symptoms are proximal symmetrical weakness of limbs and usually accompanied with extra-muscle symptoms. The MRI showed muscle edema in all patients and fatty infiltrates in some patients. Myositis-specific auto-antibodies and muscle biopsies play key roles in diagnosis of HMGCR myopathy. Corticosteroids and immunosuppressants were first line therapy. Pediatric patients or patients with chronic course are usually refractory, and the efficacy of different combinations of immunosuppressants needs to be further investigated.

Objective:To explore the effect of knockdown of the homeobox gene paired-box 6 ( Pax6) on the biological behavior and epithelial-mesenchymal transition (EMT) of human lens epithelial cells (LECs). Methods:The SRA01/04 human LECs were divided into small interfering RNA-Pax6 (siRNA-Pax6) group transfected with siRNA-Pax6 and siRNA negative control (siRNA-NC) group transfected with disordered siRNA.Cell survival rate was detected by cell counting kit-8 method at 24, 48 and 72 hours after transfection.Cell cycle distribution and apoptosis were analyzed by flow cytometry at 48 hours after transfection.Migratory capability of cells was examined by cell scratch test at 24 hours after transfection.The mRNA relative expression levels of Pax6, α-crystallin A (CRYAA), α-crystallin B (CRYAB), Sox2, α-smooth muscle actin (α-SMA) and E-cadherin were detected by quantitative real-time PCR at 48 hours after transfection.The relative expression of Pax6 protein was detected by Western blot at 48 hours after transfection.Results:There was a significant difference in cell survival rates at different time points between the two groups ( Fgroup=4.776, P<0.05; Ftime=13.535, P<0.05). The cell survival rate of siRNA-Pax6 group was obviously lower than that of siRNA-NC group at 48 and 72 hours after transfection, and the differences were statistically significant (both at P<0.05). Compared with siRNA-NC group, the proportion of cells in G 0/G 1 phase was significantly increased and the proportion of cells in S phase was significantly reduced in siRNA-Pax6 group ( t=9.971, -5.063; both at P<0.05). The cell migration rate of siRNA-Pax6 group was (19.73±6.07)%, which was lower than (70.56±2.97)% of siRNA-NC group, showing a statistically significant difference ( t=-7.245, P<0.05). The relative expressions of Sox2 mRNA and α-SMA mRNA were lower, and the relative expression of E-cadherin mRNA was higher in siRNA-Pax6 group than siRNA-NC group, with statistically significant differences between them ( t=-23.254, -5.294, 6.062; all at P<0.01). The relative expression of CRYAA mRNA and CRYAB mRNA was significantly higher in siRNA-Pax6 group than siRNA-NC group, and the differences were statistically significant ( t=5.521, 8.270; both at P<0.01). The relative expressions of Pax6 mRNA and protein in siRNA-Pax6 group were 0.27±0.01 and 0.24±0.05, respectively, which were both lower than 1.00±0.05 and 1.14±0.10 in siRNA-NC group, showing statistically significant differences ( t=-14.456, -4.458; both at P<0.001). Conclusions:Silence of Pax6 can suppress the proliferation and EMT of human LECs and enhance the expression of crystallin.

Objective:To summarize the clinical, pathological and muscle magnetic resonance imaging (MRI) features of human immunodeficiency virus (HIV)-associated nemaline myopathy (NM; HIV-NM).Methods:The present patient was a 23-year-old man with HIV infection who developed progressive proximal weakness and atrophy for more than 10 months. He was admitted to the Department of Neurology of Beijing Ditan Hospital in early June 2021. Electromyography showed myogenic findings. The serum creatine kinase was 202.4 U/L. CD 4+ count was 585×10 6/L. Serum monoclonal immunoglobulin (M protein) was negative. The patient underwent MRI examination of bilateral thigh muscles, biopsy of left biceps brachii and gene detection. The clinical, pathological and muscle MRI changes of HIV-NM were summarized based on the literature review. Results:MRI examination of bilateral thigh muscles showed edema changes. Muscle biopsy showed nemaline structures in some muscle fibers, accompanied by fiber atrophy and regeneration. No gene mutation related to clinical phenotype was found by second-generation sequencing. After intravenous immunoglobulin combined with prednisone, the patient′s weakness symptoms were significantly improved. A total of 17 cases of HIV-NM (including the present case) were identified in the literature, who were aged (33.7±9.1) years. Fifteen were males and two were females. All patients developed proximal limb weakness. Creatine kinase was normal or slightly elevated. Serum monoclonal protein was positive in 3 cases (3/7). Immunosuppressive therapy was effective.Conclusions:The main clinical characteristics of HIV-NM are progressive proximal limb weakness and muscle atrophy. The muscle pathology shows a large number of nemaline structures in atrophic muscle fibers. Muscle edema can be seen on muscle MRI. This is the first report of HIV-NM in China, which may be a special subtype of immune myopathy.

Objectives:To summarize the clinical and genetic characteristics of the patients with isolated methylmalonic acidemia and investigate the strategies for the diagnosis, treatment and prevention.Methods:Three hundred and fourteen patients (180 males, 134 females) with isolated methylmalonic acidemia were ascertained from 26 provinces or cities across the mainland of China during January 1998 to March 2020. Genetic analysis was performed by Sanger sequencing, gene panel sequencing, whole exome sequencing, multiplex ligation-dependent probe amplification or quantitative PCR. According to the age of onset, the patients were divided to early-onset group (≤12 months of age) and the late-onset group (>12 months of age). They were treated by cobalamin, L-carnitine and (or) special diet and symptomatic treatment. Statistical analysis was done using Chi-square test.Results:Fifty-eight of 314 (18.5%) patients were detected by Newborn screening using liquid chromatography tandem mass spectrometry. Five cases (1.6%) had a postmortem diagnosis. Two hundred and fifty-one patients (79.9%) were clinically diagnosed with an age of onset ranged from 3 hours after birth to 18 years. One hundred and fifty-nine patients (71.0%) belonged to early-onset groups, 65 patients (29.0%) belonged to the late-onset group. The most common symptoms were metabolic crises, psychomotor retardation, epilepsy, anemia and multiple organ damage. Metabolic acidosis and anemia were more common in early-onset patients than that in late-onset patients (20.8%(33/159) vs. 9.2% (6/65), 34.6% (55/159) vs. 16.9% (11/165), χ 2=4.261, 6.930, P=0.039, 0.008). Genetic tests were performed for 236 patients (75.2%), 96.2%(227/236) had molecular confirmation. One hundred and twenty-seven variants were identified in seven genes (MMUT, MMAA, MMAB, MMADHC, SUCLG1, SUCLA2, and MCEE), of which 49 were novel. The mut type, caused by the deficiency of methylmalonyl-CoA mutase, was the most common ( n=211, 93%) cause of this condition. c.729_730insTT, c.1106G>A and c.914T>C were the three most frequent mutations in MMUT gene. The frequency of c.914T>C in early-onset patients was significantly higher than that in late-onset patients (8.3% (18/216) vs. 1.6% (1/64), χ 2=3.859, P=0.037). Metabolic crisis was more frequent in mut type than the other types (72.6% (114/157) vs. 3/13, χ 2=13.729, P=0.001),developmental delay and hypotonia were less frequent in mut type (38.2% (60/157) vs. 9/13, 25.5% (40/157) vs. 8/13, χ 2=4.789, 7.705, P=0.030, 0.006). Of the 58 patients identified by newborn screening, 44 patients (75.9%) who were treated from asymptomatic phase developed normally whereas 14 patients (24.1%) who received treatment after developing symptoms exhibited varying degrees of psychomotor retardation. Conclusions:The characteristics of phenotypes and genotypes among Chinese patients with isolated methylmalonic acidemia were analyzed. Expanded the mutation spectrum of the associated genes. Because of the complex clinical manifestations and severe early onset of isolated methylmalonic acidemia, Newborn screening is crucial for early diagnosis and improvement of prognosis. MMUT gene is recommended for carrier screening as an effort to move the test earlier as a part of the primary prevention of birth defects.