Angular dependence of spin-flop transition in triangular lattice antiferromagnet Cu2(OH)3Br.

We report angular dependence of spin-flop transition in triangular lattice antiferromagnet Cu2(OH)3Br by angle-dependent magnetization and ESR measurements. The results show that the antiferromagnetic easy magnetization axis is the diagonal direction (θ= 45°) of theac*plane, i.e., the orientation of Cu1 spins based on the magnetic structure (2020Phys. Rev. Lett.125037204), whereas the spin-flop axis is thebaxis. A phenomenological model is proposed to describe the angle-dependent spin-flop transitions. Based on this model, Cu1 spins are sensitive to external magnetic field, while Cu2 spins are robust against to the field, showing partial decoupling. The model is expected to be used in other uniaxial antiferromagnets with a more general easy axis and complex spin-flop transitions.

[Clinical characteristics and prognostic risk factors analysis of carbapenem-resistant organism in the department of hematology].

Objective: To study the distribution and drug resistance of Carbapenem-Resistant Organism (CRO) and to analysis the risk factors of CRO 30-day mortality. Methods: A total of 181 patients with CRO infection diagnosed in Department of Hematology, Fujian Medical University Union Hospital from January 2018 to June 2020 were retrospectively investigated. The clinical and laboratory data of the patients were collected, the prognosis of patients diagnosed with CRO infection in day 30 was followed up, and the risk factors of prognosis were analyzed. The clinical significance of Carbapenem-Resistant Enterobacteriaceae (CRE) active screening was further evaluated in the CRE subgroup. Results: Among the total of 181 CRO isolates, 47.2% were CRE, 37.0% were Pseudomonas aeruginosa, and 32.6% were Klebsiella pneumoniae, which were highly resistant to carbapenem and had high MIC value, 76.8% (139/181) of CRO were MIC of imipenem resistance≥16 µg/ml. The main sources of isolates were blood and sputum. The 30-day all-cause mortality rates of patients with CRO or CRE infection were (41.4±3.7) % and (44.7±5.4) %, respectively. The COX multivariate regression analysis showed that the level of procalcitonin >0.2 ng/ml and the MIC value of imipenem resistance ≥ 16 µg/ml were independent risk factors for 30-day mortality of CRO infected patients. The CRE subgroup analysis showed that MIC value of imipenem resistance ≥16 µg/ml were independent risk factors for 30-day mortality of CRE infected patients. The 30-day cumulative survival rate of patients with CRE active screening was higher than the patients without CRE active screening [ (68.0±9.3) % vs (50.0±6.5) %, P=0.21]. Conclusion: The high MIC value of imipenem resistance isolates seriously affects the prognosis of patients with CRO infection in the hematology department, and the mortality rate was high. CRE active screening is expected for early prevention, early diagnosis, and early treatment for high-risk patients.

[Genotype and phenotype analysis of neonates with neonatal encephalopathy complicated with perinatal hypoxic event].

Objective: To explore the underlying genetic causes of neonatal encephalopathy complicated with perinatal asphyxia. Methods: From the neonates recruited to the Neonatal Genome Project of Children's Hospital of Fudan University between January 2016 and January 2019, 113 neonates with neonatal encephalopathy and acute peripartum or intrapartum event or Apgar score ≤7 were enrolled in this study. The clinical data, laboratory results, the findings of electroencephalograph and magnetic resonance imaging or head ultrasound, and the genetic information were retrospectively analyzed. Results: Of the 133 neonates with neonatal encephalopathy and acute peripartum or intrapartum event or Apgar score ≤7 scores, 77 (57.9%) were males, 56 (42.1%) were female, 56 (42.1%) were delivered via cesarean section, and 77(57.9%) were born by vaginal delivery. Among these cases, 68 (51.1%) were diagnosed of hypoxic ischemic encephalopathy, 25 (18.8%) had intracranial hemorrhage, 20 (15%) were related to genetic diseases, and 5 (3.8%) had sepsis without central nervous infection. A total of 20 cases with positive results by next-generation sequencing test were identified, including 19 cases with pathogenic variations and 1 case with variation of uncertain significance. These 20 cases included 4 cases with congenital myopathy (2 cases of MTM1 gene pathogenic variants, 1 case of ACTA1 and 1 case of RYR1 gene pathogenic variants), 4 cases with genetic syndrome (2 cases of CHD7 gene pathogenic variants, 1 case of PTN11 gene pathogenic variant, and 1 case of NSDHL gene pathogenic variant), 3 cases with metabolic disorders (1 case of OTC gene pathogenic variant, 1 case of MTHFR gene pathogenic variant, and 1 case of ALDH7A1 gene pathogenic variant), 2 cases with epileptic encephalopathy (1 case of KCNT1 and 1 case of PACS2 gene pathogenic variants), 1 case with congenital central hypoventilation syndrome (PHOX2B gene pathogenic variant) and 6 cases with copy-number pathogenic variations. Among these 20 cases, 8(40.0%) neonates were presented with persistent hypotonia, 7(35.0%) neonates with seizures, and 5(25.0%) neonates with congenital malformation. Genetic counseling and further follow-up were performed or suggested for these 20 cases; 4 neonates were deceased, 10 neonates underwent palliative care, and 6 neonates were improved after supportive care and their further follow-up plan were performed in clinics. Conclusions: Genetic diseases are not rare in neonates with neonatal encephalopathy complicated with perinatal hypoxia event. The common causes in these neonates include congenital myopathy, metabolic disorders, genetic syndrome, and epilepsy encephalopathy.

[Effects of continuous veno-venous hemodiafiltration in patients with severe Kawasaki disease complicated with multiple organ dysfunction syndrome].

Objective: To explore the effects of continuous veno-venous hemodiafiltration (CVVHDF) as a rescue therapy in children with Kawasaki disease (KD) complicated with multiple organ dysfunction syndrome (MODS). Methods: The medical records of 5 patients diagnosed as KD with MODS treated with CVVHDF, who were admitted to pediatric intensive care unit (PICU) of Shanghai Children's Hospital from November 2015 to October 2017 were retrospectively collected. The inflammatory factors and parameters of organ function before and after CVVHDF treatment were analyzed. Wilcoxon test was used to compare the changes of parameters before and after CVVHDF treatment. Results: The pediatric critical illness score (PCIS) and the pediatric risk of score mortality score Ⅲ (PRISMⅢ) were 74.0 (70.0, 81.0) and 14.5 (12.5, 17.0), respectively. The duration of CVVHDF treatment was 46.0 (24.5, 48.0) h. The levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), blood lactic acid were significantly decreased after the CVVHDF treatment (0.4 (0.1, 28.8) vs. 142.0 (123.1, 1 454.6) ng/L, Z=-2.023, P=0.043; 0.1 (0.1, 9.3) vs. 1.7(1.1, 30.0) ng/L, Z=-2.023, P=0.043; 1.2(1.1,1.4) vs. 2.5(2.4, 2.7) mmol/L, Z=-2.041, P=0.041 respectively). Moreover, the lung, liver and kidney function were significantly improved as indicated by the ratio of PaO(2) to FiO(2) (380.0 (182.5, 397.5) vs. 160.0 (52.5, 185.0)mmHg (1 mmHg=0.133 kPa), Z=2.041, P=0.041), the level of total bilirubin ((14.9±1.3) vs. (86.4±9.9) µmol/L), and the levels of creatinine (2 cases: 24.0vs. 103.0 µmol/L, 38.0 vs. 142.0 µmol/L). Conclusion: CVVHDF as an adjuvant therapy can rapidly reduce the levels of IL-6 and TNF-α,and improve the organ functions in children with KD complicated with MODS.

[Identification of mutations associated with coronary artery lesion susceptibility in Kawasaki disease by targeted enrichment of genomic region sequencing technique].

Objective: To screen and identify the mutations in Kawasaki disease by targeted enrichment of genomic region sequencing technique and investigate susceptibility genes associated with coronary artery lesion. Method: This was a case-control study.A total of 114 patients diagnosed as Kawasaki disease treated in Shanghai Children's Hospital between December 2015 and November 2016 were studied and another 45 healthy children who were physically examined in outpatient department were enrolled as control group. Patients were divided into two groups based on the results of echocardiogram. Peripheral venous blood was obtained from patients and controls. Genomic DNA was extracted. SeqCap EZ Choice libraries were prepared by targeted enrichment of genomic region technology. Then the libraries were sequenced to identify susceptibility genes associated with coronary artery lesion in patients diagnosed as Kawasaki disease.Susceptible genes were identified by Burden test, Pearson chi-square test or Fisher's exact probability test. Result: There was statistically significant difference in TNFRSF11B(rs2073618)G>C(p.N3K)mutation and GG/GC/CC genotype between Kawasaki disease group and control group(χ(2)=15.52, P=0.00). There was statistically significant difference in TNFRSF13B(rs34562254)C>T(p.P251L)mutation(χ(2)=10.40, P=0.01)and LEFTY1(rs360057)T>G(p.D322A)mutation(χ(2)=8.505, P=0.01)between patients with coronary artery lesions and those without. Conclusion: Targeted enrichment of genomic region sequencing technology can be used to do primary screening for the susceptible genes associated with coronary artery lesions in Chinese Kawasaki patients and may provide theoretical basis for larger sample investigation of risk prediction score standard in Kawasaki disease.