Objective:To investigate the clinical, pathological and genetic features of 3 cases of limb-girdle muscular dystrophy 2A (LGMD2A) caused by non-canonical splice site mutations in the CAPN3 gene. Methods:For the 3 LGMD2A patients admitted to Qilu Hospital of Shandong University from July 2016 to July 2018 were selected as the subjects. Clinical data were collected, whole exome sequencing was conducted, and the candidate variants were verified by Sanger sequencing. Total RNA was extracted from the skeletal muscle tissue of 3 probands and effects of splicing mutations on pre-mRNA splicing in the CAPN3 gene were verified by reverse-transcription polymerase chain reaction. Total protein was extracted from the muscle tissue of the probands and expression level of calpain 3 protein was detected by Western blotting. Results:All the 3 probands presented muscle weakness in upper and lower limbs, and muscle weakness in proximal limbs was more severe. Muscle biopsies all indicated myogenic impairment. Genetic sequencing showed proband 1 carried compound heterozygous c.2185-14T>G and c.2305C>T (p.R769W) mutations in the CAPN3 gene, proband 2 carried compound heterozygous c.1193+30G>A and c.2069_2070delAC (p.H690Rfs *9) mutations, and proband 3 carried homozygous c.1194-9A>G mutations in the CAPN3 gene. Splicing assay showed the c.2185-14T>G mutation located in intron 20 induced retention of the entire intron 20, the c.1193+30G>A mutation in intron 9 induced retention of the first 31 nucleotides of intron 9, and the c.1194-9A>G mutation in intron 9 induced retention of the last eight nucleotides of intron 9. Western blotting revealed deficiency of calpain 3 protein in skeletal muscle of proband 1 and proband 2. Conclusions:The clinical manifestation of LGMD2A is muscle weakness predominantly in proximal limbs, and the muscle pathology is mostly characterized by myogenic impairment.Moreover, aberrant splicing of pre-mRNA caused by non-canonical splice site mutations plays a pathogenic role in this disease.

Objective:To study the characteristics of clinical, laboratory, imaging, genetic and differential diagnosis of McLeod syndrome.Methods:The clinical characteristics of 2 cases of McLeod syndrome confirmed by gene detection in Qilu Hospital (Qingdao) on June 27, 2018 and in Qilu Hospital of Shandong University on September 11, 2019 were analyzed retrospectively. And the characteristics of patients of McLeod syndrome reported in China were analyzed in combination with literature review.Results:Both of the 2 patients were adult male, aged 57 and 61 years, respectively, with a slowly progressive course, beginning with gradually involuntary movement of trunk and extremities, involving involuntary biting of the tongue and dysphagia. Two patients had mild cognitive impairment; one patient had emotional agitation. Imaging study showed atrophy of caput nuclei caudate. Neuroelectrophysiological examination of case 1 showed sensory axon neuropathy in both upper limbs with severe damage to the left ulnar nerve. Creatine kinase (CK) was mildly elevated in 2 patients. The peripheral blood smear of 1 patient showed increased acanthocytes, accounting for 13%, the other patient showed no increased acanthocyte. McLeod syndrome related gene was tested in the 2 patients, case 1 with deletion mutation of exon 2 of XK gene, and case 2 with hemizygotic mutation of XK gene c.898delC p.L300 *. Conclusions:The clinical manifestations of McLeod syndrome are various and the differential diagnosis is crucial. For elderly male with cephalic facial chorea, elevated CK level and neuromuscular diseases, the possibility of McLeod syndrome should be screened.

Objective:To analyze the clinical phenotypic characteristics, muscle pathology, genetic mutations and related proteins of myofibrillar myopathy 3 caused by mutation in MYOT gene, and to conduct a literature review and summary of this disease. Methods:A retrospective analysis of the clinical phenotypic characteristics, muscle pathology and genetic test results of a patient with myofibrillar myopathy 3 caused by mutation in MYOT gene diagnosed in Qilu Hospital of Shandong University in December 2018 was conducted. Whole exon sequencing was applied to conduct high-throughput screening of pathogenic genes in the patient. After finding candidate pathogenic mutation, Sanger sequencing was applied to verify the mutation sites in the patient and family members. Meanwhile, functional verification was carried out on the mutation sites found in MYOT gene, and the relevant literature was reviewed. Results:The patient was a 47-year-old woman with weakness in her lower limbs for 8 years. Electromyography showed myogenic changes. The muscle pathology suggested that there was deposition of abnormal substances and rimmed vacuoles within some muscle fibers. Gene testing showed that the patient was a carrier of the MYOT gene c.170C>T (p.Thr57Ile) heterozygous mutation, and her son and daughter also carried the same mutation at the same site. The son of the patient had an elevated creatine kinase level and spontaneous potential was occasionally observed on electromyography, while the daughter had no abnormalities. Two younger brothers did not carry the mutation. Protein functional studies suggested that the mutation of MYOT gene c.170C>T mutation can lead to the change of partial spatial structure of myotilin, and the abnormal aggregation of p62 protein and myotilin was involved in the pathogenesis of the disease. Literature review revealed that c.170C>T (p.Thr57Ile) mutation has only been reported in foreign populations. This is the first detailed report on the clinical phenotype, muscle pathology and gene function of MYOT-related myofibrillar myopathy type 3 in China. Conclusions:The clinical manifestations of myofibrillar myopathy type 3 caused by MYOT gene mutation are heterogeneous, mainly manifested as muscle weakness in the distal or proximal extremities. Muscle pathology reveals abnormal protein deposits and rimmed vacuoles within some muscle fibers. Accurate diagnosis of the disease depends on gene detection. The co-localization of p62 protein and myotilin protein provides a new idea for the diagnosis and molecular mechanism research of the disease.

Temporary cardiac pacing is an essential technique in the diagnosis and treatment of arrhythmias. Due to its urgency, complexity, and uncertainty, it is necessary to develop an evidence-based emergency operation norms. Currently, there is no specific consensus guidelines at home or abroad. The Emergency Branch of Chinese Medical Association organized relevant experts to draft the Chinese emergency expert consensus on bedside temporary cardiac pacing (2023) to guide the operation and application of bedside cardiac pacing. The formulation of the consensus adopts the consensus meeting method and the evidentiary basis and recommendation grading of the Oxford Center for Evidence-based Medicine in the United States. A total of 13 recommendations were extracted from the discussion on the methods of bedside temporary cardiac pacing, the puncture site of transvenous temporary cardiac pacing, the selection of leads, the placement and placement of leads, pacemaker parameter settings, indications, complications and postoperative management. The recommended consensus includes the choice between transcutaneous and transvenous pacing, preferred venous access for temporary transvenous pacing, the target and best guidance method for implantation of bedside pacing electrodes, recommended default pacemaker settings, recommended indications for sinoatrial node dysfunction, atrioventricular block, acute myocardial infarction, cardiac arrest, ventricular and supraventricular arrhythmias. They also recommended ultrasound guidance and a shortened temporary pacing support time to reduce complications of temporary transvenous cardiac pacing, recommended bedrest, and anticoagulation after temporary transvenous pacing. Bedside temporary cardiac pacing is generally safe and effective. Accurate assessment, correct selection of the pacing mode, and timely performance of bedside temporary cardiac pacing can further improve the survival rate and prognosis of related emergency patients.
Humans ; Cardiac Pacing, Artificial/methods* ; Pacemaker, Artificial ; Arrhythmias, Cardiac/therapy* ; Myocardial Infarction/therapy* ; Electrodes

Objective: To investigate the clinical relevance of mannose-binding lectin 2 (MBL2) gene polymorphism with traumatic sepsis in Hainan Province. Methods: A retrospective case control study was conducted to analyze the clinical data of 112 severe trauma patients admitted to the First Affiliated Hospital of Hainan Medical College and Haikou People's Hospital from June 2017 to June 2018. There were 73 males and 39 females, aged 17-83 years [(41.8±8.9)years]. There were 48 patients in the sepsis group and 64 patients in the non-sepsis group. Multiplex single nucleotide extension polymorphism (SNaPshot) typing technique was used to detect the MBL2 gene polymorphism. The correlation between different genotypes and the risk of sepsis was analyzed. ELISA method was used to detect the level of MBL2 in plasma of each group. Results: Among the three polymorphic loci of MBL2 gene (rs5030737, rs1800450 and rs1800451), the mutation frequency of rs1800450 was 27.7%, while the mutation frequency of rs5030737 and of rs1800451 was 0. The genotype distribution in two groups was in accordance with Hardy-Weinberg equilibrium. The frequency of GA genotype in sepsis group was significantly higher than that in non-sepsis group (P<0.05). A allele frequency in sepsis group was also much higher than that in non-sepsis group (P<0.05). Patients with GA genotype had increased risk of traumatic sepsis when compared to GG genotype(OR=3.442, 95%CI 1.447-8.187). Allele A increased the prevalence of sepsis significantly as well when compared to allele G(OR=2.799, 95%CI 1.270-6.170). The MBL2 level in serum in sepsis patients with genotype GG and GA was significantly lower than that in non-sepsis group (P<0.05). In sepsis group, the MBL2 serum level of patients with genotype GA was obviously lower than that in patients with genotype GG (P<0.05). Conclusion MBL2 rs1800450G/A polymorphism is closely related to the occurrence of sepsis in Hainan province, and may be related to the decrease of serum MBL2 level in patients with mutant type.