[Diagnosis status and genetic characteristics analysis of Fanconi anemia in China]

Objective: To analyze the clinical and molecular diagnostic status of Fanconi anemia (FA) in China. Methods: The General situation, clinical manifestations and chromosome breakage test and genetic test results of 107 pediatric FA cases registered in the Chinese Blood and Marrow Transplantation Registry Group (CBMTRG) and the Chinese Children Blood and Marrow Transplantation Registry Group (CCBMTRG) from August 2009 to January 2022 were analyzed retrospectively. Children with FANCA gene variants were divided into mild and severe groups based on the type of variant, and Wilcoxon-test was used to compare the phenotypic differences between groups. Results: Of the 176 registered FA patients, 69 (39.2%) cases were excluded due to lack of definitive genetic diagnosis results, and the remaining 107 children from 15 hospitals were included in the study, including 70 males and 37 females. The age at transplantation treatment were 6 (4, 9) years. The enrolled children were involved in 10 pathogenic genes, including 89 cases of FANCA gene, 7 cases of FANCG gene, 3 cases of FANCB gene, 2 cases of FANCE gene and 1 case each of FANCC, FANCD1, FANCD2, FANCF, FANCJ, and FANCN gene. Compound heterozygous or homozygous of loss-of-function variants account for 69.2% (72/104). Loss-of-function variants account for 79.2% (141/178) in FANCA gene variants, and 20.8% (37/178) were large exon deletions. Fifty-five children (51.4%) had chromosome breakage test records, with a positive rate of 81.8% (45/55). There were 172 congenital malformations in 80 children.Café-au-Lait spots (16.3%, 28/172), thumb deformities (16.3%,28/172), polydactyly (13.9%, 24/172), and short stature (12.2%, 21/172) were the most common congenital malformations in Chinese children with FA. No significant difference was found in the number of congenital malformations between children with severe (50 cases) and mild FANCA variants (26 cases) (Z=-1.33, P=0.185). Conclusions: FANCA gene is the main pathogenic gene in children with FA, where the detection of its exon deletion should be strengthened clinically. There were no phenotypic differences among children with different types of FANCA variants. Chromosome break test is helpful to determine the pathogenicity of variants, but its accuracy needs to be improved.

[Bioinformatics analysis and key gene verification of sepsis myocardial macrophage microarray data based on GEO database]

Objective: Bioinformatics analysis was used to screen differentially expressed genes (DEGs) in macrophages of sepsis myocardial injury and to verify key genes. Methods: Experiment 1 (gene chip and bioinformatics analysis): The gene chip data GSE104342 of cardiac macrophages in septic mice was downloaded from Gene Expression Omnibus database. DEGs were obtained by R language analysis. DAVID online database was used to obtain gene ontology and kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis of DEGs. STRING online database was used for protein-protein interaction network analysis of DEGs, and then key genes were screened by using Cytoscape software and molecular complex detection (MCODE) plug-ins. Experiment 2 (sepsis model construction and related protein verification): Ten male C57BL/6 mice, aged 8-14 weeks. Five mice were randomly selected as control group, and 5 mice were selected as the sepsis group by building a mice sepsis model in vivo. Echocardiography was used to detect the cardiac function. Hematoxylin-eosin staining was used to assess the cardiac morphology. TUNEL staining was used to evaluate cardiomyocyte apoptosis. Immunofluorescence staining was used to detect the expression of differentiation antigen cluster 206 (CD206),inducible nitric oxide synthases (iNOS),F4/80,suppressor of cytokine signaling 3 (Socs3) ,interleukin 1 receptor antagonist (Il1rn) and chemokine C-C motif ligand 7 (Ccl7) protein. RAW264.7 macrophages were cultured in vitro and divided into 2 groups: LPS groupstimulated by lipopolysaccharide (LPS, 1 mg/L) and blank control group treated with equal-volume phosphate buffer solution. Reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate the expression of Socs3, Il1rn and Ccl7 in vitro. Results: Experiment 1: 24 647 genes were screened in GSE104342 dataset and 177 genes (0.72%) were differential expression, including 120 up-regulated genes and 57 down-regulated genes. Gene ontology enrichment analysis showed that DEGs were mainly involved in inflammatory response, immune response, apoptosis regulation and antigen processing and presentation. KEGG signaling pathway analysis showed that DEGs in cardiac macrophages of septic mice were mainly enriched in cytokine-cytokine receptor interaction, tumor necrosis factor signaling pathway, NOD like receptor signaling pathway. Three hub genes were obtained by STRING and Cytoscape analysis, including Socs3, Il1rn and Ccl7. Experiment 2: In vivo, it was found that compared with the control group, the cardiac function of the sepsis mice decreased significantly, the myocardial cells were significantly edema, inflammatory cell infiltration, myocardial fiber rupture, some myocardial nuclei dissolved and disappeared, and the cardiomyocyte apoptosis increased, suggesting that the sepsis myocardial injury model of mice was successfully constructed. Compared with the control group, the expression of CD206 in the myocardium of septic mice was down-regulated, the expression of iNOS, F4/80, Socs3, Il1rn and Ccl7 were up-regulated. In addition, there was co-localization between Socs3, Il1rn, Ccl7 and F4/80 protein. Compared with the blank control group, the expression of Socs3, Il1rn and Ccl7 significantly upregulated after LPS intervention in vitro by RT-PCR. Conclusions: The selected key genes Socs3, Il1rn and Ccl7 were up-regulated in myocardial macrophages of septic mice. Socs3, Il1rn and Ccl7 are expected to become new targets for the diagnosis and treatment of sepsis cardiac injury.

[Efficacy of decitabine combined with low dose chemotherapy on children with acute myeloid leukemia]

Objective: To evaluate the efficacy of decitabine combined with low dose chemotherapy (LDC) in the treatment of high-risk, refractory and relapsed pediatric acute myeloid leukemia (AML). Methods: Clinical data of 19 AML children treated with decitabine combined with LDC in the Department of Hematology, Children's Hospital of Soochow University from April 2017 to November 2019 were analyzed retrospectively. The therapeutic response, adverse effects and survival status were analyzed,and the outcomes of patients were followed up. Results: Among 19 AML cases, there were 10 males and 9 females. Five cases were high-risk AML, 7 cases were refractory AML, and 7 cases were relapsed AML. After one course of decitabine+LDC treatment, 15 cases achieved complete remission, 3 cases got partial remission, and only 1 case didn't get remission. All patients received allogeneic hematopoietic stem cell transplantation as consolidation therapy. The follow-up time of all cases was 46 (37, 58) months, 14 children had survived. The cumulative three-year overall survival rate was (79±9) %, events free survival rates was (68±11) %, and recurrence free survival rate was (81±10) %. The most common adverse effects related to the induction treatment were cytopenia (19 cases) and infection (16 cases).There were no treatment-related death during the therapy. Conclusion: Decitabine combined with LDC is a safe and effective option for high-risk, refractory and relapsed AML children, which provides an opportunity for HSCT.

[Ischemic preconditioning inhibits ischemia/reperfusion induced myocardial apoptosis in rabbits in vivo]

OBJECTIVE

To investigate the effects of ischemic preconditioning on myocardial apoptosis induced by ischemia/reperfusion.

METHODS

Twenty four rabbits were randomly allocated to three groups(n = 8), pseudo-operation group(group P), ischemia/reperfusion group(group IR), and ischemic preconditioning group (group IP). Group IR and group IP were subjected to three hours of left anterior descending coronary artery occlusion followed by three hours of reperfusion. Ischemic preconditioning was achieved by three 5-minute cycles of ischemia, each followed by 5 minutes of reperfusion. Infarct size and area at risk were defined by dual staining with triphenyltetrazolium chloride and Evans blue dye. DNA laddering in the border zone myocardium of ischemic area at risk was revealed with agarose gel electrophoresis, and apoptosis index(AI) was obtained with flow cytometry.

RESULTS

Infarct size, expressed as a percentage of the area at risk(IS:AR), was(60.8 +/- 10.8)% in group IR. Ischemic preconditioning reduced myocardial infarct size significantly to (33.1 +/- 4.9)% (P < 0.05). AI was (13.83 +/- 3.98)% in group IR, and were reduced significantly to (5.85 +/- 1.59)% in group IP(P < 0.01). DNA laddering indicative of fragmented DNA was clearly demonstrated in myocardial specimens sampled from the lateral border zones of the ischemic area at risk in group IR but were attenuated in group IP.

CONCLUSION

It suggests that ischemic preconditioning inhibits the rabbit myocardial apoptosis induced by ischemia/reperfusion in vivo.

[Statistical analysis of 47 cases with Holt-Qram syndrome]

By statistical analysis of 47 cases with Holt-Qram syndrome(HOS), we found that the severity of the upper limb abnormalities and cardiac defects in HOS varied significantly with different individuals. The variations of appearance were related with the types and positions of mutatons of TBX5 gene which could damage the gene function and cause HOS. It is suggested that the genetic heterogeneity in HOS may be caused by the mutations of different genes.

[Advances in the expression of foreign genes in Hansenula polymorpha]

Hansenula polymorpha is a potential host for foreign gene expression, which has been applied widely in academic studying and industry application. It has a number of advantages of expressing genes derived from eukaryotic organisms, such as mitotically stable recombinant strains, faithful processing of the produced polypeptides, and high productivity et al. Numerous foreign proteins with high commercial value have been expressed successfully in H. polymorpha, among which some have been launched on the market. In this review, the favorable characteristics of this system for foreign gene production and new advances are described.

[Protective effects of sevoflurane pretreatment on myocardial ischemia-reperfusion injury in rabbits]

To observe the myocardial protective effects of sevoflurane pretreatment on ischemia-reperfusion injury, forty eight rabbits were divided into six groups randomly: control group, ischemia-preconditioning group, sevoflurane preconditioning group, ischemia preconditioning plus glyburide group, sevoflurane preconditioning plus glyburide group, glyburide group, each group subjected to three hours of left anterion descending coronary artery occlusion followed by three hours of reperfusion. Infarct size and area at risk were defined by staining. Infarct size [expressed as a percentage of the area at risk (IS:AR)] was (60.8 +/- 10.8)% in controls, and reduced to (33.1 +/- 4.9)% and (30.9 +/- 6.8)% respectively in ischemic preconditioning groups and sevoflurane preconditioning groups. Glyburide pretreatment eliminated the preconditioning effects of ischemia and sevoflurane [IS:AR = (59.3 +/- 11.2)% and (56.6 +/- 11.9)%, respectively; not significant]. Glyburide alone did not increase infarct size [IS:AR = (63.2 +/- 12.5)%, not significant]. It suggests that sevoflurane pretreatment protects the rabbit heart subjected to three hours of coronary occlusion from infarction.

Mutations in the gene encoding gap junction protein beta-3 associated with autosomal dominant hearing impairment

Hearing impairment is the most commonly occurring condition that affects the ability of humans to communicate. More than 50% of the cases of profound early-onset deafness are caused by genetic factors. Over 40 loci for non-syndromic deafness have been genetically mapped, and mutations in several genes have been shown to cause hearing loss. Mutations in the gene encoding connexin 26 (GJB2) cause both autosomal recessive and dominant forms of hearing impairment. To study the possible involvement of other members of the connexin family in hereditary hearing impairment, we cloned the gene (GJB3) encoding human gap junction protein beta-3 using homologous EST searching and nested PCR. GJB3 was mapped to human chromosome 1p33-p35. Mutation analysis revealed that a missense mutation and a nonsense mutation of GJB3 were associated with high-frequency hearing loss in two families. Moreover, expression of Gjb3 was identified in rat inner ear tissue by RT-PCR. These findings suggest that mutations in GJB3 may be responsible for bilateral high-frequency hearing impairment.

[Cytologic diagnosis of thyroid lesions by fine needle aspiration]

Fine needle aspiration cytology was used for the diagnosis of 1914 cases of thyroid lesions. In 365 cases, cytologic findings were compared with pathohistologic findings. 310 benign lesions including 272 tumors and 38 other lesions and 55 malignant tumors were noted. The total correspondence rate was 97% and the rate of misdiagnosis 3%. Sampling and diagnostic technics were discussed.