Anti-synthase syndrome associated with SARS-Cov-2 infection.

BACKGROUND: Anti-synthetase syndrome (AS) is a rare autoimmune idiopathic inflammatory myopathy (IIM) with diverse manifestations, including arthritis, interstitial lung disease (ILD), Raynaud's phenomenon, unexplained persistent fever, and mechanic's hands. CASE PRESENTATION: We present the case of a 72-year-old woman, previously healthy, who was admitted to our hospital for treatment of cough and rapid breathing. The patient had elevated white blood cells and C-reactive protein, and tested negative for severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2). She was initially diagnosed with community-acquired pneumonia and received tamoxifen for anti-infection treatment, but her dystonia worsened. She eventually required non-invasive ventilator support, tested positive for SARS-Cov-2 again, and started antiviral therapy, corticosteroids to reduce alveolar effusion, anticoagulation, and other treatments. However, her condition continued to deteriorate, with the lowest oxygenation index reaching only 80mmHg. Ultimately, she underwent tracheal intubation and mechanical ventilation. Chest CT revealed rapid progressive interstitial changes in her lungs, and her hands showed noticeable fraternization changes. At this point, we suspected that the novel coronavirus infection might be associated with autoimmune diseases. The patient's autoimmune antibody spectrum showed positive results for anti-recombinant RO-52 antibody and myositis-specific antibody anti-alanyl tRNA synthetase (anti-PL-12). The patient was treated with dexamethasone sodium phosphate for anti-inflammatory and anti-fibrotic effects. After successful extubation, the patient was discharged with only oral prednisone tablets at a dose of 30 mg. CONCLUSIONS: This case presents an early diagnosis and successful treatment of anti-synthetase syndrome combined with SARS-Cov-2 infection, emphasizing the importance of comprehensive physical examination. Additionally, it highlights the rapid progression of interstitial lung disease under SARS-Cov-2 infection, which is often difficult to distinguish on imaging. In cases where treatment for SARS-Cov-2 infection is ineffective, early screening for autoimmune diseases is recommended. As there is currently no standardized method for treating AS-ILD, the successful treatment of this case provides a reference for clinical research on anti-synthetase syndrome in the later stage.

Reshaping the Diversity of Oxidized Polyquinane Sesquiterpenoids by Cytochrome P450s.

Polyquinane sesquiterpenoids (PQSTs) are complex compounds with two or three fused cabocyclopentane ring systems, and the biocatalysts for direct C-H bond oxidation on these scaffolds have rarely been discovered. In this study, we discovered two versatile fungal CYP450s capable of performing diverse oxidations on seven PQST scaffolds, resulting in the generation of 20 unique products. Our findings significantly expand the diversity of oxidized PQST scaffolds and provide important biocatalysts for the selective oxidation of inert carbons of terpenoids in future research.

Recent advances and new insights in biosynthesis of dendrobine and sesquiterpenes.

Sesquiterpenes are one of the most diverse groups of secondary metabolites that have mainly been observed in terpenoids. It is a natural terpene containing 15 carbon atoms in the molecule and three isoprene units with chain, ring, and other skeleton structures. Sesquiterpenes have been shown to display multiple biological activities such as anti-inflammatory, anti-feedant, anti-microbial, anti-tumor, anti-malarial, and immunomodulatory properties; therefore, their therapeutic effects are essential. In order to overcome the problem of low-yielding sesquiterpene content in natural plants, regulating their biosynthetic pathways has become the focus of many researchers. In plant and microbial systems, many genetic engineering strategies have been used to elucidate biosynthetic pathways and high-level production of sesquiterpenes. Here, we will introduce the research progress and prospects of the biosynthesis of artemisinin, costunolide, parthenolide, and dendrobine. Furthermore, we explore the biosynthesis of dendrobine by evaluating whether the biosynthetic strategies of these sesquiterpene compounds can be applied to the formation of dendrobine and its intermediate compounds. KEY POINTS: • The development of synthetic biology has promoted the study of terpenoid metabolism and provided an engineering platform for the production of high-value terpenoid products. • Some possible intermediate compounds of dendrobine were screened out and the possible pathway of dendrobine biosynthesis was speculated. • The possible methods of dendrobine biosynthesis were explored and speculated.

[Effect of Bifidobacterium on the expression of ß-defensin-2 in intestinal tissue of neonatal rats with necrotizing enterocolitis].

OBJECTIVE: To study the effect of Bifidobacterium on the expression of ß-defensin-2 (BD-2) in intestinal tissue of neonatal rats with necrotizing enterocolitis (NEC). METHODS: A total of 40 rats were randomly divided into four groups: normal control, Bifidobacterium control, NEC model, and Bifidobacterium treatment, with 10 rats in each group. A rat model of NEC was induced by hypoxia, cold stimulation, and artificial feeding. The rats in the Bifidobacterium control and Bifidobacterium treatment groups were given Bifidobacterium via the gastric tube after cold stimulation once a day for three consecutive days. The morphological changes of the terminal ileum were observed under a light microscope and the intestinal injury score was determined. Immunohistochemistry and qRT-PCR were used to measure the protein and mRNA expression of BD-2 in the ileal mucosal tissue. RESULTS: The NEC model group had a significantly higher intestinal injury score than the normal control, Bifidobacterium control, and Bifidobacterium treatment groups (P<0.05). The Bifidobacterium treatment group had a significantly higher intestinal injury score than the normal control and Bifidobacterium control groups (P<0.05). The mRNA and protein expression of BD-2 in the normal control group was significantly lower than in the Bifidobacterium control, NEC model, and Bifidobacterium treatment groups (P<0.05). The Bifidobacterium control group had significantly higher mRNA and protein expression of BD-2 than the NEC model and Bifidobacterium treatment groups (P<0.05). The Bifidobacterium treatment group had significantly higher mRNA and protein expression of BD-2 than the NEC model group (P<0.05). CONCLUSIONS: Bifidobacterium can induce the expression of BD-2 in intestinal tissue of rats and reduce inflammatory response by increasing the expression of BD-2. This provides a protective effect on neonatal rats with NEC.

All-trans-retinoic acid promotes iodine uptake via up- regulating the sodium iodide symporter in medullary thyroid cancer stem cells.

Recently, the main therapy of medullary thyroid cancer (MTC) is surgical, but by which way there is a poor prognosis with a mean survival of only 5 years. In some cases, some researchers found that it is the medullary thyroid cancer stem cells (MTCSCs) that cause metastasis and recurrence. This study aimed to eradicate MTCSCs through administration of all-trans-retinoic acid (ATRA). Here we demonstrate that MTCSCs possess stem- like properties in serum-free medium. The ABCG2, OCT4 and sodium iodide symporter (NIS) were changed by ATRA. Additionally, we found that ATRA can increase the expression of NIS in vivo. All the data suggested that ATRA could increase the iodine uptake of MTCSCs through NIS.

[Relationship between pulmonary surfactant-associated protein B polymorphisms and the susceptibility to neonatal respiratory distress syndrome].

OBJECTIVE: To study the relationship between pulmonary surfactant-associated protein B (SP-B) gene polymorphisms and their susceptibility to neonatal respiratory distress syndrome (RDS). METHODS: Eighty-eight preterm infants with RDS (RDS group) and 103 infants without RDS (control group) were enrolled. The genomic DNA was isolated using DNA kits. Polymerase chain reaction with restriction fragment length polymorphism technique was used to detect the genotype and allele frequency of the SP-B -18A/C and SP-B 1580C/T single nucleotide polymorphisms. The association between the polymorphisms and RDS was analyzed. RESULTS: SP-B -18A/C and SP-B 1580C/T were found to be polymorphic in both RDS and control groups. The frequencies of CC genotype (X2=12.26, P<0.01) and C allele (X2=11.97, P<0.01) of SP-B 1580C/T were significantly higher in the RDS group than in the control group. The C allele significantly increased the risk of RDS (OR=2.26, 95%CI: 1.42-3.60). The frequencies of genotype and allele of SP-B -18A/C showed no significant difference between the two groups. CONCLUSIONS: SP-B 1580C/T polymorphism contributes to the etiology of RDS and may serve as the susceptibility gene for RDS. The C allele increases the risk of RDS. SP-B -18A/C shows no association with the etiology of RDS.