Screening of marine resistant strain based on PKS and NRPS genes and the activity of its metabolites / 生物工程学报

Based on polyketide syntheses gene (PKS) and non-ribosomal peptide synthetases gene (NRPS), one strain with high anti-pathogenic activity was screened from 77 strains isolated from Arctic marine sediments and identified. By optimizing the composition of culture medium and fermentation conditions, the production of this strain's active metabolites was improved and the main metabolites were identified by HRMS, 1H NMR and 13C NMR. The antibacterial spectrum of the main metabolites and the effect of the metabolites on cucumber Fusarium wilt were also determined. The results showed that the strain was Bacillus velezensis and it showed growth promoting effect on plants. When the strain was cultured in 5 g/L maltose, 10 g/L tryptone, 10 g/L sodium chloride, at 30 ℃, 150 r/min for 60 h, the diameter of the inhibition zone increased from (16.23±0.42) to (24.42±0.57) mm. The metabolites of this strain mainly contain macrolide compound macrolactin A, which has antagonistic effect on a variety of pathogenic bacteria and fungi. Cucumber seedling experiments showed that the metabolites of this strain had a protective effect on cucumber Fusarium wilt, and showed a good potential for development and application as a biocontrol agent.

Analysis of genetic mutations and pathogenesis for two children with Omenn syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the clinical characteristics and genetic mutations in two children with Omenn syndromes.</p><p><b>METHODS</b>Peripheral venous blood samples were collected from 2 children suspected with severe combined immunodeficiency (SCID) and their family members. The samples were subjected to RAG1 and RAG2 gene sequencing and TCR Vβ subclone analysis.</p><p><b>RESULTS</b>Both patients had recurrent infections, erythroderma rashes and alopecia baldness. One patient has fit with immunophenotype T-B-NK+, while another was consistent with typical Omenn syndrome combined with T+B-NK+ immunophenotype, IgE and eosinophil increase. Both children have carried compound heterozygous mutations of the RAG1 gene. The first patient carried c.1328 G>A (p.R443K) and c.2486-2490delGGAAA (p.R829fsX869) mutations, both were of de novel type. The second patient has carried c.1209C>T (p.R403W) and c.2892delT (p.ASN964LYSfs*14), with c.2892delT (p.ASN964LYSfs*14) being a de novel mutation. The parents of both patients were heterozygous carriers. The same mutations were not found in 100 healthy children. Both patients' 24 TCR Vβ subfamilies have presented monoclonal or oligoclonal peaks, with TCR Vβ polymorphism being severely disrupted.</p><p><b>CONCLUSION</b>Three novel mutations have been identified in two children with Omenn syndrome, which featured early onset and rapid progression. Early recognition of the disease and prompt treatment may reduce the mortality.</p>

Interleukin-10 receptor mutations in children with neonatal onset inflammatory bowel disease: genetic diagnosis and pathogenesis / 中华儿科杂志

<p><b>OBJECTIVE</b>To explore use of interleukin-10 receptor (IL-10R) gene mutation in diagnosis and pathogenesis of neonatal inflammatory bowel disease (IBD) in 2 suspected cases.</p><p><b>METHOD</b>Two cases of sibling brothers who had suspected IBD from Guangzhou Women and Children's Medical Center Affiliated to Guangzhou Medical University during the year 2010-2014 were enrolled in the study. The proband, male, 26 days old, weight 3.73 kg, presented with recurrent fever, increased stool frequency since 9 days of age, and was hospitalized at the age of 6 months in 2014. The proband's brother, male, 6 months old, weight 8 kg, had repeated bloody and mucous diarrhea for more than five months, recurrent fever five days, and was hospitalized in 2010. The blood samples were collected from the children and their families for IL-10 receptor genes including IL-10 receptor α subunit (IL-10RA) and β subunit (IL-10RB) PCR amplification. Reverse transcription polymerase chain reaction (RT-PCR) was used to amplify the proband IL-10RA transcripts. Sequencing was performed on the PCR products forward and reversely. Western blot analysis was used for protein expression of the proband and normal control's IL-10RA and P-STAT3 (Tyr705) expression after IL-10 stimulation, TNF-α level was detected using Human TNF-α ELISA Kit after PBMC was cultured and stimulated.</p><p><b>RESULT</b>The proband and his brother were IBD patients. Genome sequencing showed mutation in c.537G>A, namely the exon 4 and intron 4 connections changed CA/GT for CG/GT. Sequencing of the RT-PCR products and T-A clone showed that the mutation was (c.519-537del GGTGCCGGGAAACTTCAC, p.LYS173ASNfs*7), as the splice mutation. Two gene mutations were novel mutation. The parents were the mutations carrier. Both of the children were compound heterozygous mutations in IL-10RA. The Western blot analysis showed that the patient and normal children can express IL-10RA protein, however, the function of IL-10RA had obvious defects in the patient, IL-10RA downstream signaling pathways P-STAT3 had no expression. The average level of TNF-α secreted by PBMC after LPS + IL-10 co-stimulation in patient was significantly increased as compared with control group ((2 100±356) vs. (200±50) ng/L, t=9.154, P=0.001), suggesting that interleukin-10-dependent negative feedback regulation is disrupted in the patient.</p><p><b>CONCLUSION</b>IL-10 receptor mutations can cause neonatal-IBD, for which common treatment effect is poor. Early diagnosis and allogeneic stem-cell transplantation performed may save the children's life.</p>

Nitoprusside, dopamine and dobutamine for treatment of refractory heart failure / 中国基层医药

Objective To observe the clinical effect of nitroprusside,dopamine and dobutamine for treatment of refractory heart failure. Methods 60 patients with refractory heart failure were randomly divided into control group and treatment group. Clinical symptoms, signs, echocardiography and other changes were observed. Results The total effective rate was 86.67% ,control group was 66.67% ,the total effective between the two groups was statistically significant(P ＜ 0.05). After treatment, left ventricular ejection fraction (LVEF) improved significantly compared with the control group, the difference was statistically significant(P ＜ 0.05). Conclusion The Sodium nitroprusside, dopamine and dobutamine for treatment of refractory heart failure was safe and effective method.