Report of the Largest Chinese Cohort With SLC19A3 Gene Defect and Literature Review.

Thiamine metabolism dysfunction syndrome 2 (THMD2) is a rare metabolic disorder caused by SLC19A3 mutations, inherited in autosomal recessive pattern. As a treatable disease, early diagnosis and therapy with vitamin supplementation is important to improve the prognosis. So far, the reported cases were mainly from Saudi Arab regions, and presented with relatively simple clinical course because of the hot spot mutation (T422A). Rare Chinese cases were described until now. In this study, we investigated 18 Chinese THMD2 patients with variable phenotypes, and identified 23 novel SLC19A3 mutations, which expanded the genetic and clinical spectrum of the disorder. Meanwhile, we reviewed all 146 reported patients from different countries. Approximately 2/3 of patients presented with classical BTBGD, while 1/3 of patients manifested as much earlier onset and poor prognosis, including infantile Leigh-like syndrome, infantile spasms, neonatal lactic acidosis and infantile BTBGD. Literature review showed that elevated lactate in blood and CSF, as well as abnormal OXPHOS activities of muscle or skin usually correlated with infantile phenotypes, which indicated poor outcome. Brainstem involvement on MRI was more common in deceased cases. Thiamine supplementation is indispensable in the treatment of THMD2, whereas combination of biotin and thiamine is not superior to thiamine alone. But biotin supplementation does work in some patients. Genotypic-phenotypic correlation remains unclear which needs further investigation, and biallelic truncated mutations usually led to more severe phenotype.

The combination of whole-exome sequencing and copy number variation sequencing enables the diagnosis of rare neurological disorders.

This retrospective study aims to investigate the diagnostic yields of multiple strategies of next-generation sequencing (NGS) for children with rare neurological disorders (NDs). A total of 220 pediatric patients with NDs who visited our hospital between Jan 2017 and Dec 2018 and had undergone NGS were included. Most patients were 5 years old or younger, and the number of patients visiting the hospital decreased with age. Seizures were the most common symptom in this cohort. The positive rates for targeted NGS panels (Panel), whole-exome sequencing (WES), and copy number variation sequencing (CNVseq) were 26.5% (9/34), 36.6% (63/172), and 16.7% (22/132), respectively. The positive rate for patients undergoing a combination of WES and CNVseq (WES + CNVseq) was 47.8% (54/113), which was significantly better than the positive rate for patients who underwent WES alone (32.7%, 37/113). A total of 83 variants were found in 42 genes, and SCN1A was the most frequently mutanted gene. Twenty-four CNVs were identified in 22 patients: two CNVs were inherited from the mother; 12 CNVs were de novo; and the CNV origins could not be determined in 10 patients. WES + CNVseq may potentially be the mostly effective NGS approach for diagnosis of rare NDs in pediatric patients.

Physical stabilities of taro starch nanoparticles stabilized Pickering emulsions and the potential application of encapsulated tea polyphenols.

In this research, Pickering emulsion stabilized by taro starch nanoparticles was successfully prepared, and the potential application of encapsulating tea polyphenols was investigated. The nanoparticle size (about 460 nm) and contact angle (81.5°) of taro starch indicate that it is suitable for adsorbing on the oil-water interface and forming a dense interfacial layer. Emulsion stability at different particle concentrations, oil-water ratios, and sodium chloride concentrations has been systematically studied. By considering the particle size, zeta potential, and stability index of Pickering emulsion, it is considered that the emulsion has the best stability when the particle concentration is 7% and the oil fraction is 0.5. Low concentration of salt ions (0.04 mM NaCl) will cause a slight flocculation to improve the stability, but adding high concentration of salt will make emulsion break. In addition, we found that this Pickering emulsion could encapsulate the tea polyphenols greatly with a retention rate of up to 67%. The findings may have great significance for the design and fabrication of native starch particle stabilized emulsion.

Antibacterial activities of R-(+)-Limonene emulsion stabilized by Ulva fasciata polysaccharide for fruit preservation.

It was previously found that R-(+)-Limonene emulsion could be stabilized by Ulva fasciata polysaccharide. In the present study, emulsions of R-(+)-Limonene were developed for coating of strawberries to improve the shelf life and microbiological safety. Edible coatings with at least 0.15% w/w of R-(+)-Limonene improved the microbial stability of the strawberries, resulted effective in the decontamination of external pathogens such as Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Changes in weight loss, total soluble solid (TSS), pH, total phenolic, ascorbic acid, textural properties and surface color of strawberries during storage were evaluated. R-(+)-Limonene emulsions were effective for decreasing water loss of all the fruit samples tested. The decrease in TSS values was higher in the control strawberries. Initial decreases followed by increases of pH during storage of strawberries. The amount of total phenols detected in control fruit sharply increased during the first 6 days then remained steady, whereas the total soluble phenols content of treated strawberries gradually increased during storage. Strawberries coated with emulsion had higher L* and a* values as compared to control fruits. The R-(+)-Limonene coatings have demonstrated the potential to inhibit foodborne pathogen contamination of strawberries, and prolong their shelf life.