Biomedical subjects

Shuxian Li

Publications and source records attributed to Shuxian Li.

5 recordsLinked to original sources

PubMed2026

Identification of a novel and a recurrent CDC45 variant in a Chinese family with Meier-Gorlin syndrome 7 and a literature review.

INTRODUCTION: Meier-Gorlin syndrome 7 (MGORS7) is a rare autosomal recessive disorder characterized by primordial dwarfism, craniosynostosis, and patellar aplasia, caused by pathogenic variants of CDC45. Here, we report a Chinese patient presenting with classic hallmarks of MGORS7 alongside atypical clinical features, including hearing and visual impairments. METHODS: Clinical and radiological data were collected. Whole-genome sequencing and Sanger sequencing were performed to identify and validate the causative variants. Their functional effects were investigated using an exon-trapping assay, and a literature review of previously reported MGORS7 cases was conducted. RESULTS: Genetic analysis identified two compound heterozygous CDC45 variants: c.1416C>T (p.H472=) and c.1559+2T>A, which are a recurrent variant in the East Asian population and a novel variant, respectively. Our exon-trapping assay indicated that c.1559+2T>A induced aberrant splicing, generating transcripts predicted to undergo nonsense-mediated mRNA decay. Additionally, growth hormone therapy was initiated in our patient, with a noted improvement in growth parameters in the initial assessment and without immediate complications. The literature review identified a total of 32 CDC45 variants in 29 patients with MGORS7, who showed high heterogeneity in clinical phenotypes. DISCUSSION: Our study further expanded the mutational spectrum of CDC45 and provided a preliminary clinical observation suggesting that growth hormone therapy may be beneficial for growth retardation in patients with MGORS7.

CDC45↗

PubMed2006

Modification of phenolic metabolism in soybean hairy roots through down regulation of chalcone synthase or isoflavone synthase.

Soybean hairy roots, transformed with the soybean chalcone synthase (CHS6) or isoflavone synthase (IFS2) genes, with dramatically decreased capacity to synthesize isoflavones were produced to determine what effects these changes would have on susceptibility to a fungal pathogen. The isoflavone and coumestrol concentrations were decreased by about 90% in most lines apparently due to gene silencing. The IFS2 transformed lines had very low IFS enzyme activity in microsomal fractions as measured by the conversion of naringenin to genistein. The CHS6 lines with decreased isoflavone concentrations had 5 to 20-fold lower CHS enzyme activities than the appropriate controls. Both IFS2 and CHS transformed lines accumulated higher concentrations of both soluble and cell wall bound phenolic acids compared to controls with higher levels found in the CHS6 lines indicating alterations in the lignin biosynthetic branch of the pathway. Induction of the soybean phytoalexin glyceollin, of which the precursor is the isoflavone daidzein, by the fungal pathogen Fusarium solani f. sp. glycines (FSG) that causes soybean sudden death syndrome (SDS) showed that the low isoflavone transformed lines did not accumulate glyceollin while the control lines did. The (iso)liquritigenin content increased upon FSG induction in the IFS2 transformed roots indicating that the pathway reactions before this point can control isoflavonoid synthesis. The lowest fungal growth rate on hairy roots was found on the FSG partially resistant control roots followed by the SDS sensitive control roots and the low isoflavone transformants. The results indicate the importance of phytoalexin synthesis in root resistance to the pathogen.

Acyltransferases↗

PubMed2002

A Stachybotrys chartarum isolate from soybean.

As part of our effort to investigate fungi associated with soybean roots, Stachybotrys chartarum was isolated from soybean root lesions. Since this fungus has not been reported to cause a disease of soybean, the objectives were to identify and characterize this fungus using biological, chemical, and molecular approaches. Fungal morphology was examined using light and environmental scanning electron microscopy. Phialides bearing conidia arose from determinate, macronematous, dark olivaceous conidiophores. The phialides were obovate or ellipsoidal in whorls. Conidia were unicellular, round or ellipsoidal, 5-13 x 4-7 microm, initially hyaline with smooth walls then dark brown to black and rough-walled when mature. Radial growth of the fungus on cornmeal, oatmeal and potato dextrose agar was 38, 47, and 33 mm in diam., respectively, after 10 days at 25 degrees C. Pathogenicity was performed using sorghum grain colonized by S. chartarum placed below sown soybean seeds in a soil: sand (1:1) steam-pasteurized mix. Three weeks after inoculation, root lesions ranged from 7 to 25 mm long. The fungus was reisolated from soybean root lesions and was reidentified as S. chartarum. Biochemical analysis indicated that this soybean isolate produced satratoxins G and H along with roridin L-2, as well as the spircyclic lactones and lactams in rice culture. PCR using a S. chartarum-specific primer StacR3 and IT51 amplified a 198-bp DNA fragment from the total genomic DNA. The DNA sequence of the ITS region was 100% identical to the S. chartarum strain ATCC 9182, one nucleotide mismatch with S. chartarum strain UAMH 7900, and differed from all published sequences of 12 other species of Stachybotrys and 2 species of Memnoniella in GenBank with genetic divergence ranging from 5.26 to 9.98%. This molecular evidence further supports the identification of S. chartarum isolated from soybean root lesions.

Chromatography, High Pressure Liquid↗

PubMed2002

Prevalence of cerebral palsy in children aged 1 - 6 in Guangxi, China.

OBJECTIVE: To study the prevalence of cerebral palsy (here in after referred to CP) in children aged 1 - 6 in Guangxi, China, and its epidemiologic characteristics and relevant risk factors. METHODS: Investigations on the prevalence and etiology of CP in children at ages of 1 - 6 were conducted in Nanning, Hengxian and Qinzhou of Guangxi from June to December in 1998, with a cluster sampling. RESULTS: Totally, 150 806 children aged 1 - 6 were investigated in Nanning, Hengxian and Qinzhou of Guangxi, with 89 418 boys and 61 388 girls. Among them, 193 children were diagnosed as CP, with a prevalence rate of 1.28 per thousand, higher in boys (136 cases, 1.52 per thousand ) than in girls (57 cases, 0.93 per thousand ), with statistical significance (chi(2) = 9.536 7, P = 0.02). Logistic regression analysis showed that risk factors for CP were children who could not cry after birth (neonatal asphyxia), Apgar score less than eight, delivery at lower level of maternity hospital, number of mother's gravidity, no prenatal checks for mothers, and taking antipyretics and preserved food with salt during pregnancy. CONCLUSIONS: Prevalence of CP in children of Guangxi was at a lower level in comparison with that in other areas at home and abroad, which, maybe, was related with the lower neonatal survival and higher infant mortality.

Cerebral Palsy↗

PubMedDate not supplied

Isoflavonoid accumulation in soybean hairy roots upon treatment with Fusarium solani.

Hairy roots were initiated from two soybean [Glycine max (L.) Merr.] genotypes with different susceptibility (susceptible 'Spencer' and partially resistant 'PI567.374') to the disease sudden death syndrome (SDS) caused by the soil-borne fungal pathogen Fusarium solani f. sp. glycines (FSG) to study the role of isoflavonoids in the plant response to FSG infection. Hairy root cultures obtained by transformation with Agrobacterium rhizogenes allows normal root growth that can be visually monitored. The principal isoflavones (genistin, daidzin, glycitin and their malonyl conjugates and aglycones) and also isoflavonoid phytoalexins (coumestrol and glyceollin) were measured by HPLC in extracts of the FSG-inoculated and non-inoculated hairy roots. FSG mycelia grew more slowly on inoculated PI567.374 hairy roots than on Spencer hairy roots. The glyceollin content was higher in FSG-inoculated PI567.374 hairy roots than in Spencer hairy roots even though the glyceollin precursor, the isoflavone daidzein, was higher in Spencer. The de novo synthesis of isoflavones and glyceollin was confirmed by [(14)C]Phe incorporation into glyceollin, which was higher both in the FSG-inoculated roots and surrounding medium of the cv. PI567.374 than that of Spencer. Glyceollin was the most inhibitory to FSG growth among eight isoflavonoids tested. The levels of coumestrol, a putative phytoalexin, did not change upon FSG inoculation. The defense response was also elicited by FSG culture filtrates in hairy roots grown in liquid culture. The data obtained indicate that the ability of soybean roots to rapidly produce sufficient amounts of glyceollin in response to FSG infection might be important in providing partial resistance to this fungus.

Benzopyrans↗