Objective:To investigate renal impairment and ferroptosis due to severe blast injuries and related mechanism.Methods:The goats were placed 3 meters away from the center of an 8 kg TNT-equivalent explosive to carry out blast injury experiments.The physical parameters of blast waves were measured,and the pathological severity of blast injuries was graded and scored to assess the severity of injuries.Vital signs,blood gas parameters,and renal function markers were measured before injury and at 1,3,6,and 24 hours after injury.Renal tissue samples were collected at 24 hours after injury to prepare tissue sections,which were used to perform HE staining and measure the changes in the content of Fe2+and the expression of the ferroptosis-related marker proteins xCT and GPX4 in renal tissue,and Prussian blue staining was performed for renal tissue sections to investigate the mechanism associated with renal impairment and ferroptosis of renal cells.Results:Severe blast injuries accounted for the highest proportion of 47.2%in experi-mental goats,while mild,moderate,severe,and extremely severe injuries accounted for 2.8%,36.1%,47.2%,and 13.9%,respectively,and the pathologic severity score of blast injury was 2.56±0.15.For the goats after blast injury,there were significant increases in heart rate(F=12.750,P<0.01)and respiratory rate(F=6.500,P<0.01)and significant reductions in anal temperature(F=3.496,P<0.05),partial pressure of blood oxygen(F=24.630,P<0.01),and blood oxygen saturation(F=18.560,P<0.01),as well as significant increases in the levels of blood uric acid(F=22.320,P<0.01),serum creatinine(F=15.350,P<0.01),and blood urea nitrogen(F=22.310,P<0.01).Compared with the control group,swelling of renal tubular epithelial cells and narrowing of tubular lumen were observed at 24 hours after blast injury,with a significant increase in the content of Fe2+in renal tissue(t=5.933,P<0.01),significant reductions in the relative expression protein levels of GPX4(t=7.924,P<0.01)and xCT(t=4.483,P<0.01)in renal tissue,and deposi-tion of a large amount of iron ions in renal tubular epithelial cells.Conclusion:Experimental goats placed 3 meters away from the cen-ter of an 8 kg TNT-equivalent explosive can cause severe blast inju-ries,resulting in the onset of hypoxia,renal impairment,and ferrop-tosis of renal tubular epithelial cells.

Objective:To explore the clinical manifestation, efficacy and treatment strategies in patients with severe warm autoimmune hemolytic anemia (w-AIHA).Methods:A total of 21 patients with w-AIHA who were hospitalized in Children′s Hospital of Capital Institute of Pediatrics from June 2007 to March 2019 were included, and the clinical characteristics, treatment strategies and responses were retrospectively analyzed.Results:A total of 21 children with severe w-AIHA had an average age of 8.0 (2.5, 20.0) months and a follow-up time of 33.0 (18.5, 110.0) months.In 10 (47.6%) cases, the hemoglobin levels were lower than 30 g/L.Evans′ syndrome was diagnosed in five(23.8%) cases.Five (23.8%) cases were secondary cases.Nine (42.8%) cases had a previous infection history and two cases were pollen-induced.Five (23.8%) cases had hemolytic crisis.A total of 12 (57.1%) cases had cross-matching difficulty.Eight (38.1%) cases were admitted to the ICU, and five (23.8%) cases had shock.All children received corticosteroids and intravenous immunoglobulin, 16 (76.2%) cases were treated with second-line regimens (cyclophosphamide and rituximab, etc.), 15 cases had complete response, three cases had partial response and three cases had no response and died.Conclusion:Infection is an important predisposing factor in children with severe w-AIHA, and secondary cases have a higher proportion, mainly caused by immunodeficiency disease.Patients tend to have a high incidence of hemolytic crisis and have difficulty in matching and transfusion.Therefore, transfusion is the key for successful rescue.It is suggested that children with severe w-AIHA require ICU admission for early monitoring and rituximab should be applied in advance to ensure successful transfusion.

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.

OBJECTIVE: To explore the clinical, neuropathological and genetic characteristics of a patient with Perrault syndrome caused by TWNK mutation. METHODS: Potential variation of the TWNK gene was detected by next-generation sequencing (NGS) and verified by Sanger sequencing. RESULTS: The patient has featured primary amenorrhoea and progressive sensorineural hearing loss since childhood. She also had gait anormaly, distal limb atrophy and weakness, and nystagmus. Further study confirmed sensory neuronopathy accompanied with upper and lower motor neuron involvement as well as cerebellum atrophy. NGS has identified two heterozygous variants of the TWNK gene, namely c.794G>A (p.Arg265His) and c.1181G>A (p.Arg394His). Sanger sequencing confirmed that c.1181G>A (p.Arg394His), a known pathogenic variant, was derived from her farther, while c.794G>A(p.Arg265His), a novel variant, was derived from her mother and likely pathogenic according to the ACMG guidelines. CONCLUSION Perrault syndrome is a group of disorders with a high phenotypic heterogeneity. The compound heterozygous variation of c.794G>A (p.Arg265His) and c.1181G>A(p.Arg394His) of the TWNK gene may underlie Perrault syndrome in the patient.
Child ; Female ; Genetic Testing ; Gonadal Dysgenesis, 46,XX ; Hearing Loss, Sensorineural ; Humans ; Pedigree

Objective To investigate the antimicrobial resistance profile of the clinical isolates collected from selected hospitals across China. Methods Twenty-nine general hospitals and five children's hospitals were involved in this program. Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems. Results were interpreted according to CLSI 2017 breakpoints. Results A total of 190 610 clinical isolates were collected from January to December 2017, of which gram negative organisms accounted for 70.8％ (134 951/190 610) and gram positive cocci 29.2％ (55 649/190 610). The prevalence of methicillin-resistant strains was 35.3％ in S. aureus (MRSA) and 80.3％ in coagulase negative Staphylococcus (MRCNS) on average. MR strains showed much higher resistance rates to most of the other antimicrobial agents than MS strains. However, 91.6％ of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 86.2％ of MRCNS strains were susceptible to rifampin. No staphylococcal strains were found resistant to vancomycin. E. faecalis strains showed much lower resistance rates to most of the drugs tested (except chloramphenicol) than E. faecium. Vancomycin-resistant Enterococcus (VRE) was identified in both E. faecalis and E. faecium. The identified VRE strains were mainly vanA, vanB or vanM type based on phenotype or genotype. The proportion of PSSP or PRSP strains in the non-meningitis S.pneumoniae strains isolated from children decreased but the proportion of PISP strains increased when compared to the data of 2016. Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 10％ of these strains (excluding Klebsiella spp.) were resistant to carbapenems. The prevalence of imipenem-resistant K. pneumoniae increased from 3.0％ in 2005 to 20.9％ in 2017, and meropenem-resistant K. pneumoniae increased from 2.9％ in 2005 to 24.0％ in 2017, more than 8-fold increase. About 66.7％ and 69.3％ of Acinetobacter (A. baumannii accounts for 91.5％) strains were resistant to imipenem and meropenem, respectively. Compared with the data of year 2016, P. aeruginosa strains showed decreasing resistance rate to carbapenems. Conclusions Bacterial resistance is still on the rise. It is necessary to strengthen hospital infection control and stewardship of antimicrobial agents. The communication between laboratorians and clinicians should be further improved in addition to surveillance of bacterial resistance.

Objective: To analyz the current situation of the diagnosis, treatment and prevention of methylmalonic acidemia, the phenotypes, biochemical features and genotypes of the patients in the mainland of China, were investigated. Methods: Tottally 1 003 patients of methylmalonic acidemia from 26 provinces and municipalities of the mainland of China were enrolled. The clinical data, biochemical features and gene mutations were studied. Blood aminoacids and acylcarnitines, urine organic acids, and plasma total homocysteine were determined for the biochemical diagnosis. Gene analyses were performed for the genetic study of 661 patients. The patients were treated with individual intervention and long-term follow up. Prenatal diagnoses were carried out for 165 fetuses of the families. Results: Among 1 003 patients (580 boys and 423 girls), 296 cases (29.5%) had isolated methylmalonic acidemia; 707 cases (70.5%) had combined homocysteinemia; 59 patients (5.9%) were detected by newborn screening; 944 patients (94.1%) had the onset at the ages from several minutes after birth to 25 years and diagnosed at 3 days to 25 years of age. The main clinical presentations were psychomotor retardation and metabolic crisis. Multi-organ damage, including hematological abnormalities, pulmonary hypertension, kidney damage, were found. MMACHC, MUT, MMAA, MMAB, HCFC1, SUCLG1, SUCLA2 mutations were found in 631 patients (96.6%) out of 661 patients who accepted gene analysis. MMACHC mutations were detected in 460 patients (94.7%) out of 486 cases of methylmalonic acidemia combined with homocysteinemia. MUT mutations were found in 158 (90.3%) out of 169 cases of isolated methylmalonic acidemia. The development of 59 patients detected by newborn screening were normal; 918 cases (97.2%) were diagnosed after onset accepted the treatment. Forty-five of them completely recovered with normal development. Twenty-six patients (2.7%) died; 873 (92.5%) patients had mild to severe psychomotor retardation. Methylmalonic acidemia were found in 35 out of 165 fetuses by metabolites assay of amniotic fluid and amniocytes gene analysis. Conclusion Combined methylmalonic acidemia and homocysteinemia is the common type of methylmalonic acidemia in the mainland of China. CblC defect due to MMACHC mutations is the most common type of methylmalonic acidemia combined with homocysteinemia. MUT gene mutations are frequent in the patients with isolated methylmalonic acidemia. Newborn screening is key for the early diagnosis and the better outcome. Combined diagnosis of biochemical assays and gene analysis are reliable for the prenatal diagnosis of methylmalonic acidemia.

Hemangioma is the most common vascular tumor in the infantile period.Ultrasound is noninvasive and less expensive with good reproducibility.Nowadays,a wide variety of ultrasound techniques has been applied to diagnose and stage infantile hemangioma.The progresses of ultrasound in diagnosis of infantile hemangioma were reviewed in this article.

Objective To investigate G protein-coupled estrogen receptor(GPER)mediated neuroprotective effect and mechanism in an ischemic stroke model. Methods Bilateral ovariectomy (OVX)was used to establish a castrated model of adult SPF grade female SD rats. Enzyme-linked immunosorbent assay was used to detect serum estrogen level at 4 weeks after procedure.Middle cerebral artery occlusion(MCAO)was use to prepare a stroke model.The rats were randomly divided into sham operation(n=6),MCAO(n=7),MCAO+estrogen(MCAO+E2,n=8),MCAO+agonist(MCAO+G1,n=8)and MCAO +antagonist G15(MCAO +G15,n =7)groups. The neurological severity score (NSS),2,3,5-triphenyltetrazolium chloride(TTC)staining were used to measure the volume of cerebral infarction in order to assess the effects of different interventions.Western blot was used to detect the protein expression of hypoxia inducible factor-1α(HIF-1α),c-Jun N-terminal kinase(JNK),and Caspase-3 in the ischemic penumbra. Results (1)Estrogen level:after OVX,The level of serum estrogen in rats was significantly lower than that before castration(20 ± 9 ng/L vs. 73 ± 21 ng/L,P <0. 01).(2)NSS score:the NSS score of MCAO in each group was significant higher than that in the sham operation group (P<0.01);The NSS score of the MCAO+G1 group was significantly lower than that of the MCAO group and the MCAO+G15 group(6.0 ±1.8 vs.11.9 ±2.0 and 10.0 ±2.1).The difference was statistically significant (all P<0.05).(3)Cerebral infarct volume:there was significant difference in infarcted volume between the sham operation group and all other groups(all P<0.01);Compared with the MCAO group and the MCAO+G15 group,the infarct volume of the MCAO+E2 group and MCAO+G1 group was significantly reduced(19.8 ± 4.0%,14.0 ± 2.9%)vs.29.7 ± 5.8% and 27.6 ± 3.6%).The difference was statistically significant (all P<0.05).(4)Results of Western blot:the relative optical density values of HIF-1α,JNK,and Caspase-3 of the MCAO group were higher than those of the MCAO + G1 group(all P <0.01). Conclusions GPER mediates the neuroprotective effect of estrogen in the ischemic stroke model.This protective effect is associated with the regulation of the expression levels of HIF-1α,JNK,and Caspase-3.

Objective To prepare multi-modality melanin-based lipid nanobubbles (MNBs) contrast agents,and to investigate their manifestations of ultrasound (US),photoacoustic (PA) and MRI in vitro.Methods MNBs and lipid nanobubbles (NBs) were prepared with the method of CHCl3-injection,freeze-drying and C3F8-inflation.The characteristics (shape,grain diameter,loading capacity of melanin and stability) of MNBs were obseved.US,PA and MRI were detected in vitro and the images were quantitatively analyzed.Results MNBs presented with homogenized size distribution,and transmission electron microscope (TEM) images demonstrated that the melanin particles were successfully entrapped into nanobubbles.Meanwhile,the loading capacity of melanin was 90.53 μg/mg.US signal increased in vitro with the rise of MNBs and NBs concentration.The ultrasonic manifestations of MNBs and NBs were the same,and the relative signal enhancement had no significant difference (P＞0.05).With the increased concentration of MNBs,the PA and MRI signals were stronger,but NBs showed no evident enhancement.Conclusion Multi-modality MNBs contrast agents are prepared successfully,which can enhance US,PA and MR imaging.