[Clinical and StAR genetic characteristics of 33 children with congenital lipoid adrenal hyperplasia]

Objective: To analyze the clinical and genetic characteristics of 33 children with congenital lipoid adrenal hyperplasia (CLAH) caused by StAR gene defects. Methods: The clinical, biochemical, genetic, and follow-up (until December 2021) data of 33 children diagnosed with CLAH from 2006 to 2021 were retrospectively analyzed in Xinhua Hospital, Shanghai Jiao Tong University School of Medicine. Results: Of the 33 children with CLAH, 17 had a karyotype of 46, XX and 16 had a karyotype of 46, XY; 31 were female and 2 were male by social gender. Classic type and non-classic type were found in 30 and 3 children respectively. The age at diagnosis was 9.0 (3.0, 34.5) months. All the 30 cases with classic CLAH presented within the first year of life with skin hyperpigmentation (28 cases, 93%), vomiting and(or) diarrhea (19 cases, 63%), no increase in body weight (8 cases, 27%), elevated adrenocorticotropic hormone levels (21cases (70%)>275 pmol/L), decreased cortisol levels (47 (31,126) nmol/L), hyponatremia ((126±13) mmol/L), hyperkalemia ((5.7±1.1) mmol/L), and normal 17α-hydroxyprogesterone levels (30 cases, 100%). All these with classic CLAH exhibited female external genitalia. Three children with non-classic CLAH (including 2 cases of 46, XY and 1 case of 46, XX) also showed signs and symptoms of adrenal insufficiency, but 2 of them had an age of onset later than 1 year of age, including 1 case of 46, XY with male external genitalia and 1 case of 46, XX with female external genitalia. The other 46, XY patient with non-classic CLAH presented with adrenal insufficiency at 2 months of age, showing micropenis and hypospadias. In the 17 females with 46, XX, 4 older than 10 years of age showed spontaneous pubertal development. A total of 25 StAR gene pathogenic variants were identified in 33 patients, with p.Q258* (18/66, 27%), p.K236Tfs*47 (8/66, 12%) and p.Q77* (6/66, 9%) being the common variantion. Six novel variants were found, including c.358T>G, c.713_714del, c.125del, c.745-1G>A, c.179-2A>C, and exon 1 deletion. Conclusions: Patients with classic CLAH typically present with signs and symptoms of primary adrenal insufficiency in the early infancy period and female external genitalia. p.Q258*, p.K236Tfs*47 and p.Q77* are common variants in CLAH patients.

[Composition Characteristics and Construction Mechanism of Microbial Community on Microplastic Surface in Typical Redox Environments]

Microplastics are widely distributed in the biogeochemical cycle driven by microbes. Their surface is enriched with unique microbial communities, called plastispheres. Various redox environments that exist widely in the natural environment can affect the microbial composition in the plastisphere and the fate of the microplastics. To explore the microbial community composition and construction mechanism on the surface of microplastics in typical redox environments, three microplastics, PHA (polyhydroxyalkanoates), PLA (polylactic acid), and PVC (polyvinyl chloride), were placed in five specific redox environments:aerobic, nitrate reduction, iron oxide reduction, sulfate reduction, and methane production. The culture experiment simulated the microcosm, which was inoculum by sludge. The results showed that microplastic factors affected 18.94% and 46.67% of the microbial communities on the plastisphere in taxonomy and phylogeny, respectively. Redox factors affected 31.04% and 90.00% of the microbial communities on the plastisphere in taxonomy and phylogeny, respectively. Compared with that in sludge, the microbial community richness and diversity were reduced on the three microplastics. The most apparent reduction was found on the plastisphere of more degradable PHA. At the same time, microbial communities on the refractory PLA and PVC surfaces remained similar. Anaerocolumna (26.44%) was the dominant genus on the surface of PHA microplastics, whereas microbes related to the redox reaction were less enriched. Clostridium_sensu_stricto_7 (15.49% and 11.87%) was the dominant strain on PLA and PVC microplastics, and the microbes related to the redox reaction were significantly enriched. Thus, characteristic microbes involved in the redox reaction will be enriched in the surface of refractory microplastics, and microplastics may affect the rate of biogeochemical cycling.

[Analysis of six children with 3-methylglutaconic aciduria]

Objective: To explore the clinical characteristics, genotypes and long-term outcomes of individuals with 3-methylglutaconic aciduria. Methods: The clinical features, biochemical data, genetic test results and treatment outcomes of six children with 3-methylglutaconic aciduria admitted to the Department of Endocrinology, Genetics and Metabolism, Xinhua Hospital from February 2017 to February 2019 were retrospectively analyzed and the Gesell developmental diagnosis schedule was performed to evaluate the development of four patients. Results: Among 6 children with 3-methylglutaconic aciduria 2 were males and 4 were females.Four cases had 3-methylglutaconic aciduria type Ⅰ and 2 cases had 3-methylglutaconic aciduria with deafness,encephalopathy, and Leigh-like syndrome. Five of 6 patients were detected by newborn screening among whom 4 remained asymptomatic, and only one had a postmortem diagnosis. Among them, 4 patients remained asymptomatic, while two presented with clinical symptoms such as jaundice and dyspnea and the age of disease onset was 1 and 2 days respectively. The concentration of 3-methylglutaconic acid in urine of all affected individuals was between 22.38 and 77.09 mmol/molCr, which was above the normal value. Genetic tests were performed for all patients. Eleven variants were identified in 2 genes, of which 10 variants were novel and only c.442C>T p.(R148X) has been previously reported; Seven variants (c.656-2delA, EX5-EX6 Del, c.942+3A>G, c.373C>T p.(R125W), c.895-3C>G, c.667C>T p.(R223X) and c.894+5G>A) were in AUH gene. The others (c.548G>A p.(R138Q), c.442C>T p.(R148X), c.1339C>T p.(R447X) and c.973dupA p.(M325Nfs*5) were in SERAC1 gene. After being treated with leucine diet restriction and L-carnitine, 4 patients with AUH gene variation who were from asymptomatic phase developed normally, whereas those 2 patients with SERAC1 gene variation had a poor prognosis. During the follow-up, 2 patients exhibited varying degrees of psychomotor retardation, the rest had normal course of development. Conclusions: There are significant clinical heterogeneities among individuals with 3-methylglutaconic aciduria. The most common pathogenic variants are splicing variations, followed by nonsense, missense and frameshift mutations. Leucine-free diet and oral L-carnitine therapy are effective for some patients. Newborn screening is essential for early diagnosis and improvement of prognosis.

A highly efficient diatomic nickel electrocatalyst for CO2 reduction

We report a facile but effective approach to construct a highly dispersed diatomic catalyst. A carbon-embedded diatomic Ni2 catalyst was synthesized from carbon black, polyaniline and nickel(ii) salts. The resulting catalyst exhibits excellent activity for the CO2 reduction reaction (CO2RR) at low Ni content with a faradaic efficiency of CO over 95% in the potential range from -0.6 V to -1.0 V vs. reversible hydrogen electrode (RHE). A high specific current density of 37.2 A mg-1 Ni was recorded at -1.1 V, among the highest reported values for Ni-based electrocatalysts.

Self-Assembled Peptide Functionalized Gold Nanopolyhedrons with Excellent Chiral Optical Properties

Because of the unique optical properties of gold nanomaterials, the preparation of gold nanomaterials with excellent chirality has received extensive attention. In order to develop a simple fabrication method for three-dimensional chiral Au nanostructures with a size of several hundred nanometers, chiral gold nanoparticles were developed to transfer chirality of a peptide to gold nanoparticles. In this study, the controlled synthesis of asymmetric gold nanopolyhedrons was achieved. The asymmetric gold nanopolyhedrons prepared via peptide-directed growth can exhibit strong circular dichroism (∼±50 mdeg) couplets in the visible range (500-600 nm). Also, the morphology of chiral Au nanododecahedrons-peptide particles showed distorted and asymmetric properties. In order to prove that the size and spatial structure of gold nanopolyhedrons have an influence on their chiral optical properties, Au nanotrioctahedron-peptide particles were prepared by using Au nanotrioctahedrons with different morphologies. Au nanotrioctahedron-peptide particles also exhibited circular dichromatic couplets in the visible region.

[Applying multiplex ligation-dependent probe amplification in the diagnosis of 5 cases with ornithine transcarbamylase deficiency]

OBJECTIVE

To detect large genomic deletions or duplications of ornithine transcarbamylase (OTC) gene by multiplex ligation-dependent probe amplification (MLPA).

METHOD

Thirty cases of suspected OTC deficiency (OTCD) patients based on tandem-mass spectrum results were recruited in Xinhua Hospital from 2012 to 2014, among whom 13 were male and 17 were female. Sanger sequencing of OTC gene revealed mutations in 23 cases. MLPA was performed in the patients whose previous Sanger sequencing failed to detect any disease-causing mutation. The samples were treated via the steps of DNA degeneration, the probe hybridization, connecting the hybridization probe, PCR amplification and capillary electrophoresis. The data were analyzed using Coffalyser software.

RESULT

Abnormal MLPA results were found in 5 patients without mutation detected in previous Sanger sequencing. Patient 1, a 9-year old girl, had a heterozygous deletion of Exon 2-4. Patient 2, a male newborn, died 10 days after birth. The examination of the mother's sample by MLPA revealed a heterozygous duplication of exon 2-6. Patient 3, a 10-day old boy, was found to harbor a hemizygous deletion of exon 7-10. Patient 4, a 2-year old girl, harbored a heterozygous deletion of exon 1-4. The fifth patient died at the age of 6 years, and his mother carried a heterozygous duplication of exon 1-4.

CONCLUSION

MLPA can be helpful in detecting the OTC gene defects, particularly for OTCD patients without mutation detected by Sanger sequencing.

Cloning a novel endo-1,4-β-D-glucanase gene from Trichoderma virens and heterologous expression in E. coli

Endo-1,4-β-d-glucanase (EG), as a key constituent of cellulase taking the responsibility of cutting β-1,4 glycosidic bonds, plays the essential role in the process of degrading cellulose by cellulase. Cloning and expressing the EG gene is important to the cellulase research and application. In this work, a novel EG gene was cloned from Trichoderma virens ZY-01, which was a cellulase secreting microbe isolated by our laboratory. The DNA sequence showed that the length of the cloned EG is 1069 bp, which had 95.2% similarity to the EG IV from T. viride AS 3.3711. Further, the expression vector pET-32a-EG was constructed and was successfully heterologously expressed in Escherichia coli. The expression product was purified with Ni²⁺ affinity chromatography and its enzymatic properties were investigated. The SDS-PAGE showed the target protein is 39 kDa, which is consistent with the translated result from the DNA sequence. The kinetic parameter for the expression product was K_m = 13.71 mg/mL and V_max=0.51 μmol/min·mL. The optimal reaction pH and temperature was pH = 7.0 and T = 40 °C, which is similar to the native EG produced by Trichoderma virens ZY-01. It provides the foundation for the endo-1,4-β-d-glucanase further evolution and application.

[Analysis of phenotypes and genotypes in 66 patients with 21-hydroxylase deficiency identified by neonatal screening]

OBJECTIVE

To analyze the phenotype-genotype correlation of 21-hydroxylase deficiency (21-OHD) patients found by neonatal screening, and to investigate the characteristics of gene frequency of these patients.

METHOD

Clinical and biochemical data of 66 21-OHD patients diagnosed by neonatal screening in department of pediatric endocrinology and genetics and neonatal screening center of Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from 2009 to 2014 were retrospectively analyzed. Point mutations of CYP21A2 gene were analyzed by Sanger sequencing, and large gene deletions were detected by multiplex ligation-dependent probe amplification (MLPA). Then the correlation between phenotypes and genotypes of these patients were analyzed.

RESULT

(1) Forty-one out of 66 patients who presented adrenal crisis or other signs of salt loss at age range from 4 days to 2 months were classified as salt-wasting forms. The remaining 25 patients did not present any signs of salt loss at preliminary diagnosis (12 days-2 months). (2) Definite mutations of CYP21A2 gene on two alleles were found in all 66 patients (132 alleles). A total of thirteen types of different point mutations (98/132, 74.2%), large gene deletions (24/132, 18.2%) and clusters of point mutations (10/132, 7.6%) were found. The most frequent point mutations were I2G, p. I173N, p. R357W, p. G111Vfs*21 and p. Q319*, accounting for 65.2% of alleles. (3) Phenotype and genotype correlation analysis was performed in 41 21-OHD patients with salt wasting forms. Predicted phenotypes according to genotypes in 36 (87.8%) of the 41 patients were consistent with their actual phenotypes. In 4 out of the 41 patients, the actual phenotypes were different from predicted phenotypes according to their genotypes. And in one patient, prediction of phenotype could not be made based on genotype as carrying an unknown function mutation on one allele.

CONCLUSION

Adrenal crisis or other signs of salt loss were found in 62% of 21-OHD patients at age range from 4 days to 2 months. In 66 Chinese 21-OHD children, total mutation frequency of I2G, p. I173N, p. R357W, p. G111Vfs*21 and p. Q319* accounted for 65.2% of alleles. In 87.8% of patients with salt wasting forms, predicted phenotypes according to genotypes were consistent with their actual phenotypes.

[Construction of a eukaryotic vector expressing E2F-1 Gene and its effect on proliferation of gastric cancer cell line MKN-45]

BACKGROUND & OBJECTIVE

E2F-1 is overexpressed in many tumors and functions as an oncogene or tumor suppressor gene. This study was to construct the recombinant eukaryotic vector expressing E2F-1 cDNA, and explore the effect of E2F-1 overexpression on the proliferation of human gastric carcinoma cell line MKN-45.

METHODS

The fragment of E2F-1 gene was amplified by polymerase chain reaction (PCR). A eukaryotic vector expressing E2F-1 (pCMV-E2F1-HA) was constructed with pCMV-HA, and transfected into COS-7 cells to identify whether E2F-1 was successfully subcloned into the eukaryotic vector. pCMV-E2F1-HA was transfected into MKN-45 cells. The expression of E2F-1 in MKN-45 cells was detected by Western blot. The proliferation of MKN-45 cells was observed by colony formation assay and MTS method. Cell cycle was analyzed by flow cytometry (FCM).

RESULTS

Recombinant plasmid pCMV-E2F1-HA was successfully constructed and transfected into COS-7 and MKN-45 cells. MKN-45 cell clones were significantly fewer in pCMV-E2F1-HA group than in pCMV-HA group (4.7+/-1.8 vs. 30.2+/-6.7, P<0.01). The proliferation rate of MKN-45 cells was significantly lower in pCMV-E2F1-HA group (73.5% on Day 5, 63.5% on Day 6, 56.1% on Day 7) than in pCMV-HA group (100%, P<0.01). The G0/G1 phase proportion of MKN-45 cells was significantly higher in pCMV-E2F1-HA group than in pCMV-HA group (71.4% vs. 59.7%, P<0.05); the S phase proportion was significantly lower in pCMV-E2F1-HA group than in pCMV-HA group (18.7% vs. 30.7%, P<0.05).

CONCLUSION

Overexpression of E2F-1 suppresses the proliferation of gastric cancer MKN-45 cells.