Gene function characterization in Aspergillus niger using a dual resistance marker transformation system mediated by Agrobacterium tumefaciens.

Aspergillus niger is a well-known workhorse for the industrial production of enzymes and organic acids. This fungus can also cause postharvest diseases in fruits. Although Agrobacterium tumefaciens-mediated transformation (ATMT) based on antibiotic resistance markers has been effectively exploited for inspecting functions of target genes in wild-type fungi, it still needs to be further improved in A. niger. In the present study, we re-examined the ATMT in the wild-type A. niger strains using the hygromycin resistance marker and introduced the nourseothricin resistance gene as a new selection marker for this fungus. Unexpectedly, our results revealed that the ATMT method using the resistance markers in A. niger led to numerous small colonies as false-positive transformants on transformation plates. Using the top agar overlay technique to restrict false positive colonies, a transformation efficiency of 87 ± 18 true transformants could be achieved for 106 conidia. With two different selection markers, we could perform both the deletion and complementation of a target gene in a single wild-type A. niger strain. Our results also indicated that two key regulatory genes (laeA and veA) of the velvet complex are required for A. niger to infect apple fruits. Notably, we demonstrated for the first time that a laeA homologous gene from the citrus postharvest pathogen Penicillium digitatum was able to restore the acidification ability and pathogenicity of the A. niger ΔlaeA mutant. The dual resistance marker ATMT system from our work represents an improved genetic tool for gene function characterization in A. niger.

Oral nutritional supplementation with dietary counseling improves linear catch-up growth and health outcomes in children with or at risk of undernutrition: a randomized controlled trial.

Introduction: Childhood undernutrition is associated with increased morbidity, mortality and a high socio-economic burden. Methods: Supporting Pediatric GRowth and Health OUTcomes (SPROUT) is a randomized, controlled trial evaluating the effects of an oral nutritional supplement (ONS) with dietary counseling (DC; n = 164) compared to a DC-only group who continued consuming their habitual milk (n = 166; NCT05239208). Children aged 24-60 months who were at risk or with undernutrition, as defined by weight-for-age [WAZ] < -1 and height-for-age [HAZ] < -1 according to the WHO Growth Standards, and who also met the criterion of weight-for-height [WHZ] < 0, were enrolled in Vietnam. Results: ONS + DC had a larger WAZ increase at day 120 (primary endpoint) vs. DC (least squares mean, LSM (SE): 0.30 (0.02) vs. 0.13 (0.02); p < 0.001), and larger improvements in all weight, BMI and weight-for-height indices at day 30 and 120 (all p < 0.01). Height gain was larger in ONS + DC in all indices, including height-for-age difference [HAD; cm: 0.56 (0.07) vs. 0.10 (0.07); p < 0.001], at day 120. ONS + DC had larger arm muscle but not arm fat indices, higher parent-rated appetite, physical activity and energy levels, longer night sleep, fewer and shorter awakenings, and better sleep quality than DC. Conclusion: Adding ONS to DC, compared to DC-alone, improves growth in weight and height, linear catch-up growth, and health outcomes in children with or at risk of undernutrition.

Transfer of natural radionuclides from soil to water spinach (Ipomoea aquatica Forssk) under flooded and unflooded conditions in Hanoi, Vietnam.

Transfer of natural radionuclides from soil to water spinach (Ipomoea aquatica Forssk) in Hanoi, Vietnam have been investigated using a low background gamma spectrometer with an HPGe detector (Model-GC5019). Twenty pairs of soil and water spinach samples in two environmental conditions, i.e., flooded and unflooded, were collected for measuring the activity concentrations and determining the soil-to-plant transfer factors (TFs) of natural radionuclides. For water spinach, stems and leaves were collected as the main parts for human consumption and livestock food. The TF of 40K is within the range of 0.32-2.49, which is greater than that of 228Ra (0.01-0.17) and 226Ra (0.01-0.13). The geometric means (geometric standard deviations) of the TFs are 1.17(1.89), 0.05(2.41) and 0.04(1.88) for flooded sites, and 0.89(1.73), 0.03(2.12) and 0.03(1.82) for unflooded sites, respectively. Comparing between the flooded and unflooded sites, the TFs are all greater at the flooded sites.

Application of short tandem repeats (STRs) in the preimplantation genetic diagnosis (PGD) of α-thalassemia.

OBJECTIVES: α-thalassemia is an autosomal recessive monogenic blood disorder, affecting up to 5% of the world's population. The occurrence rate of the disease in Vietnam varies up to up to 51.5%, with high rate of mutation carriers, of couples consisting of two carriers at risk of bearing a child with fetal Hb Bart, which can develop into hydrops fetalis syndrome, threatening the well-being of the mother and the child. Our study aims to facilitate birth of healthy/asymptomatic children of α-thalassemia carrier couples who received reproductive service at our centre during the period of 2019-2022. MATERIALS AND METHODS: 89 couples at risks of having α-thalassemia offsprings requested IVF procedures and PGD at Post Hospital during 2019-2022 were recruited for investigation. Couple and additional family members' peripheral blood samples of couples and additional family members were subjected to haemoglobin electrophoresis, DNA extraction for α-thalassemia gene mutation detection and STRs linkage analysis. Data were observed and analysed on GeneMarker software. RESULTS: 91 cycles of PGD for α-thalassemia were carried out for 89 couples. α-thalassemia large deletion (--SEA/αα) was the most common mutation identified in 88 couples, in which 4 cases also carried ß-thalassemia point mutations. Combining results of PGS and PGD, 278/424 amplified embryos were transferable (HBA-mutation free or carriers of single heterozygous HBA mutation, without chromosomal abnormality). 64/89 couples have been transferred with the embryos (prioritizing mutation free ones over carriers), resulting in the birth of 36 α-thalassemia disease-free children, 17 ongoing pregnancies, and 11 with miscarriages. CONCLUSION: Successful application of microsatellite-based method in PGD facilitated the birth of 36 healthy children and 17 ongoing pregnancies for 53/64 couples with embryo-transferred. All resulted clinical births displayed confirmation results in line with the PGD results, thus demonstrating the feasibility and credibility of the use of STR markers in PGD.

A novel IGHMBP2 variant and clinical diversity in Vietnamese SMARD1 and CMT2S patients.

Background: Pathogenic variants in the IGHMBP2 gene are associated with two distinct autosomal recessive neuromuscular disorders: spinal muscular atrophy with respiratory distress type 1 (SMARD1; OMIM #604320) and Charcot-Marie-Tooth type 2S (CMT2S; OMIM #616155). SMARD1 is a severe and fatal condition characterized by infantile-onset respiratory distress, diaphragmatic palsy, and distal muscular weakness, while CMT2S follows a milder clinical course, with slowly progressive distal muscle weakness and sensory loss, without manifestations of respiratory disorder. Methods: Whole-exome sequencing of the IGHMBP2 gene was performed for eight Vietnamese patients with IGHMBP2-related neuromuscular disorders including five patients with SMARD1 and the others with CMT2S. Results: We identified one novel IGHMBP2 variant c.1574T > C (p.Leu525Pro) in a SMARD1 patient. Besides that, two patients shared the same pathogenic variants (c.1235 + 3A > G/c.1334A > C) but presented completely different clinical courses: one with SMARD1 who deceased at 8 months of age, the other with CMT2S was alive at 3 years old without any respiratory distress. Conclusion: This study is the first to report IGHMBP-2-related neuromuscular disorders in Vietnam. A novel IGHMBP2 variant c.1574T > C (p.Leu525Pro) expressing SMARD1 phenotype was detected. The presence of three patients with the same genotype but distinct clinical outcomes suggested the interaction of variants and other factors including relating modified genes in the mechanism of various phenotypes.

Repeating exon 2 mutation caused by trans-splicing dystrophin gene in Duchenne muscular dystrophin (DMD) patient

The dystrophin gene is the largest human gene. Mutations in this gene cause Duchenne muscular dystrophin (DMD) disease. This is complex genomic unit exhibiting many errors splicing during mRNA process. More than 10 alternative splicing products have been identified in the 5' region of the dystrophin gene. In this study, two dystrophin transcripts including one containing exon 2 and exon X duplications, other one containing single exon 2 duplication were identified in peripheral blood lymphocytes of DMD case. Interestingly, genomic Southern blot analysis ruled out the hypothesis of duplication of dystrophin at exon 2. Therefore, these data suggested that exon 2 duplication transcripts were likely generated by trans-splicing event that occurring during the mARN maturation in which RNA segments of two independent transcripts are spliced together to generate a new mRNA species. However, the mechanisms modulating the trans-splicing activity of the dystrophin exon 2 remain to be clarified.

Mutation in the Rod domain of dystrophin gene caused Duchenne muscular dystrophy disease

Analysis of gene mutation at AND degree on 2 patients with Duchenne having clinical complications: muscle weakness occurred early and progressive, enlarged leg muscles, increased CK level in peripheral blood, muscle biopsy present specific image of the disease. 19 exon were the most commonly mutated on dystrophin gene were selected to implement PCR reaction. Results showed that exon 45 had partial deletion phenomenon in all two patients while exon 44 and 48 had not this model. The patients were determined as bearing consecutive partial delete mutation of three exon 45, 46, 47 on dystrophin gene. This mutation caused incorrect coding frame

Investigating one case of deletion of 27 exons espanding at rod domain of dystrophin gene in a Duchenne Muscular Dystrophy

A majority deletion of 27 exons expanding from 8-34 at rod domain of dystrophic gene was identified in a Duchene Muscular Dystrophy (DMD) patients. Polymerase chain reaction (PCR) was used to analyze the deletion. The deletion caused an out of frame mutation leading to nonsense mutation which early stops code in exon 35 of dystrophic gene. The DMD gene was analyzed at both genomic DNA and mRNA levels. Identification of deletion at mRNA level is very useful for rapid diagnosis of DMD patients and avoid missing some mutations that we can’t identify at DNA level

To diagnosis 85 Duchene/Becker muscular dystrophy Vietnamese patients by Polymerase chain reaction (PCR) method

AND samples of 85 Duchenne/Becker muscular dystrophy patients treated at Department of Endocrinology, Pediatric Hopital Swede-Ha Noi were analyzed. Patients were diagnosed based on typical clinical characteristic of disease, increasing plasma CK concentration and family prehistory. The result showed that mutation is quite common, concentrating mainly at 5’ final region and central region, analyzing 19 exons among 79 exons of total dystrophin gene have been detected nearly 40% patient with mutation of wipe section. Appling PCR method to determine mutation on 19 typical exons will allow fastly and exactly diagnosis