Genetic Modulation of RNA Splicing with a CRISPR-Guided Cytidine Deaminase.

RNA splicing is a critical mechanism by which to modify transcriptome, and its dysregulation is the underlying cause of many human diseases. It remains challenging, however, to genetically modulate a splicing event in its native context. Here, we demonstrate that a CRISPR-guided cytidine deaminase (i.e., targeted-AID mediated mutagenesis [TAM]) can efficiently modulate various forms of mRNA splicing. By converting invariant guanines to adenines at either 5' or 3' splice sites (SS), TAM induces exon skipping, activation of alternative SS, switching between mutually exclusive exons, or targeted intron retention. Conversely, TAM promotes downstream exon inclusion by mutating cytidines into thymines at the polypyrimidine tract. Applying this approach, we genetically restored the open reading frame and dystrophin function of a mutant DMD gene in patient-derived induced pluripotent stem cells (iPSCs). Thus, the CRISPR-guided cytidine deaminase provides a versatile genetic platform to modulate RNA splicing and to correct mutations associated with aberrant splicing in human diseases.

Haplotype-specific MAPK3 expression in 16p11.2 deletion contributes to variable neurodevelopment.

Recurrent proximal 16p11.2 deletion (16p11.2del) is a risk factor for diverse neurodevelopmental disorders with incomplete penetrance and variable expressivity. Although investigation with human induced pluripotent stem cell models has confirmed disruption of neuronal development in 16p11.2del neuronal cells, which genes are responsible for abnormal cellular phenotypes and what determines the penetrance of neurodevelopmental abnormalities are unknown. We performed haplotype phasing of the 16p11.2 region in a 16p11.2del neurodevelopmental disorders cohort and generated human induced pluripotent stem cells for two 16p11.2del families with distinct residual haplotypes and variable neurodevelopmental disorder phenotypes. Using transcriptomic profiles and cellular phenotypes of the human induced pluripotent stem cell-differentiated cortex neuronal cells, we revealed MAPK3 to be a contributor to dysfunction in multiple pathways related to early neuronal development, with altered soma and electrophysiological properties in mature neuronal cells. Notably, MAPK3 expression in 16p11.2del neuronal cells varied on the basis of a 132 kb 58 single nucleotide polymorphism (SNP) residual haplotype, with the version composed entirely of minor alleles associated with reduced MAPK3 expression. Ten SNPs on the residual haplotype were mapped to enhancers of MAPK3. We functionally validated six of these SNPs by luciferase assay, implicating them in the residual haplotype-specific differences in MAPK3 expression via cis-regulation. Finally, the analysis of three different cohorts of 16p11.2del subjects showed that this minor residual haplotype is associated with neurodevelopmental disorder phenotypes in 16p11.2del carriers.

Similarity of Chinese and Pakistani oral microbiome.

Oral microbiota is vital for human health and can be affected by various factors (i.e. diets, ethnicity). However, few studies have compared oral microbiota of individuals from different nationalities in the same environment. Here, we explored the assembly and interaction of oral microbial communities of Chinese and Pakistanis in one university. Firmicutes and Proteobacteria were the predominant microorganisms in the oral cavity of Chinese and Pakistanis. Streptococcus and Neisseria were the dominant genera of China, while Streptococcus and Haemophilus were the dominant genera of Pakistanis. In addition, the oral community membership and structure were not influenced by season, Chinese/Pakistani student and gender, reflecting the stability of the human oral microbiome. The beta diversity of oral microbiomes between Chinese and Pakistanis significantly differed in winter, but not in spring. The alpha diversity of Chinese students and Pakistani students was similar. Moreover, oral microbial community of both Chinese and Pakistani students was mainly driven by stochastic processes. The microbial network of Chinese was more complexity and stability than that of Pakistanis. Our study uncovers the characteristics of human oral microbiota, which is of great significance for oral and human health.

Multi-omics analysis identifies rare variation in leptin/PPAR gene sets and hypermethylation of ABCG1 contribute to antipsychotics-induced metabolic syndromes.

Antipsychotic-induced metabolic syndrome (APs-induced Mets) is the most common adverse drug reaction, which affects more than 60% of the psychiatric patients. Although the etiology of APs-induced Mets has been extensively investigated, there is a lack of integrated analysis of the genetic and epigenetic factors. In this study, we performed genome-wide, whole-exome sequencing (WES) and epigenome-wide association studies in schizophrenia (SCZ) patients with or without APs-induced Mets to find the underlying mechanisms, followed by in vitro and in vivo functional validations. By population-based omics analysis, we revealed that rare functional variants across in the leptin and peroxisome proliferator-activated receptors (PPARs) gene sets were imbalanced with rare functional variants across the APs-induced Mets and Non-Mets cohort. Besides, we discovered that APs-induced Mets are hypermethylated in ABCG1 (chr21:43642166-43642366, adjusted P < 0.05) than Non-Mets, and hypermethylation of this area was associated with higher TC (total cholesterol) and TG (triglycerides) levels in HepG2 cells. Candidate genes from omics studies were furtherly screened in C. elegans and 17 gene have been verified to associated with olanzapine (OLA) induced fat deposit. Among them, several genes were expressed differentially in Mets cohort and APs-induced in vitro/in vivo models compared to controls, demonstrating the validity of omics study. Overexpression one of the most significant gene, PTPN11, exhibited compromised glucose responses and insulin resistance. Pharmacologic inhibition of PTPN11 protected HepG2 cell from APs-induced insulin resistance. These findings provide important insights into our understanding of the mechanism of the APs-induced Mets.

Mammalian carcass decay increases carbon storage and temporal turnover of carbon-fixing microbes in alpine meadow soil.

Corpse decomposition is of great significance to the carbon cycle of natural ecosystem. Carbon fixation is a carbon conversion process that converts carbon dioxide into organic carbon, which greatly contributes to carbon emission reduction. However, the effects of wild animal carcass decay on carbon-fixing microbes in grassland soil environment are still unknown. In this research, thirty wild mammal (Ochotona curzoniae) corpses were placed on alpine meadow soil to study the carbon storage and carbon-fixing microbiota succession for a 94-day decomposition using next-generation sequencing. Our results revealed that 1) the concentration of total carbon increased approximately 2.24-11.22% in the corpse group. 2) Several carbon-fixing bacterial species (Calothrix parietina, Ancylobacter rudongensis, Rhodopseudomonas palustris) may predict the concentration of total carbon. 3) Animal cadaver degradation caused the differentiation of carbon-fixing microbiota structures during succession and made the medium-stage networks of carbon-fixing microbes more complicated. 4) The temporal turnover rate in the experimental groups was higher than that in the control groups, indicating a quick change of gravesoil carbon-fixing microbiota. 5) The deterministic process dominates the assembly mechanism of experimental groups (ranging from 53.42% to 94.94%), which reflects that the carbon-fixing microbial community in gravesoil can be regulated. Under global climate change, this study provides a new perspective for understanding the effects of wild animal carcass decay on soil carbon storage and carbon-fixing microbes.

AUF1 protects against ferroptosis to alleviate sepsis-induced acute lung injury by regulating NRF2 and ATF3.

BACKGROUND: The AU-rich element (ARE)-binding factor 1 (AUF1) acts as a switch for septic shock, although its underlying mechanisms remain largely unknown. In this study, we examined the biological significance and potential molecular mechanism of AUF1 in regulating ferroptosis in sepsis-induced acute lung injury (ALI). METHODS: Alveolar epithelial cells (AECs) challenged with ferroptosis-inducing compounds and cecum ligation and puncture (CLP)-induced ALI were used as the in vitro and in vivo model, respectively. The stability of AUF1 and its degradation by ubiquitin-proteasome pathway were examined by cycloheximide chase analysis and co-immunoprecipitation assay. The regulation of AUF1 on nuclear factor E2-related factor 2 (NRF2) and activation transcription factor 3 (ATF3) was explored by RNA immunoprecipitation (RIP), RNA pull-down, and mRNA stability assays. Functionally, the effects of altering AUF1, NRF2 or ATF3 on ferroptosis in AECs or ALI mice were evaluated by measuring cell viability, lipid peroxidation, iron accumulation, and total glutathione level. RESULTS: AUF1 was down-regulated in AECs challenged with ferroptosis-inducing compounds, both on mRNA and protein levels. The E3 ubiquitin ligase FBXW7 was responsible for protein degradation of AUF1 during ferroptosis. By up-regulating NRF2 and down-regulating ATF3, AUF1 antagonized ferroptosis in AECs in vitro. In the CLP-induced ALI model, the survival rate of AUF1 knockout mice was significantly reduced and the lung injuries were aggravated, which were related to the enhancement of lung ferroptosis. CONCLUSIONS: FBXW7 mediates the ubiquitination and degradation of AUF1 in ferroptosis. AUF1 antagonizes ferroptosis by regulating NRF2 and ATF3 oppositely. Activating AUF1 pathway may be beneficial to the treatment of sepsis-induced ALI.

CRISPR/Cas9-mediated ß-globin gene knockout in rabbits recapitulates human ß-thalassemia.

ß-thalassemia, an autosomal recessive blood disorder that reduces the production of hemoglobin, is majorly caused by the point mutation of the HBB gene resulting in reduced or absent ß-globin chains of the hemoglobin tetramer. Animal models recapitulating both the phenotype and genotype of human disease are valuable in the exploration of pathophysiology and for in vivo evaluation of novel therapeutic treatments. The docile temperament, short vital cycles, and low cost of rabbits make them an attractive animal model. However, ß-thalassemia rabbit models are currently unavailable. Here, using CRISPR/Cas9-mediated genome editing, we point mutated the rabbit ß-globin gene HBB2 with high efficiency and generated a ß-thalassemia rabbit model. Hematological and histological analyses demonstrated that the genotypic mosaic F0 displayed a mild phenotype of anemia, and the heterozygous F1 exhibited typical characteristics of ß-thalassemia. Whole-blood transcriptome analysis revealed that the gene expression was altered in HBB2-targeted when compared with WT rabbits. And the highly expressed genes in HBB2-targeted rabbits were enriched in lipid and iron metabolism, innate immunity, and hematopoietic processes. In conclusion, using CRISPR-mediated HBB2 knockout, we have created a ß-thalassemia rabbit model that accurately recapitulates the human disease phenotype. We believe this tool will be valuable in advancing the investigation of pathogenesis and novel therapeutic targets of ß-thalassemia and associated complications.

hUCMSCs carrying exenatide prevent T1DM by improving intestinal microflora composition and islet tissue damage repair.

BACKGROUND: Exenatide is a stable analogue of glucagon-like peptide 1 that can reduce postprandial hyperglycemia and has been utilized as adjunctive therapy for type 1 diabetes mellitus (T1DM). The human umbilical cord is a rich source of MSCs, and human umbilical cord mesenchymal stem cells (hUCMSCs) also show potential to enhance insulin secretion. Here, we aimed to explore the effects of hUCMSCs carrying exenatide in T1DM and further identify the possible mechanisms involved. METHODS: hUCMSCs were isolated from human umbilical cord tissues, identified, and transduced with recombinant lentivirus carrying exenatide to obtain exenatide-carrying hUCMSCs (hUCMSCs@Ex-4). RESULTS: The results showed that hUCMSCs@Ex-4 restored the blood glucose levels and body weight of NOD mice, and repressed immune cell infiltration and islet tissue changes. Additionally, in T1DM mice, treatment with hUCMSCs@Ex-4 reduced the blood glucose levels and promoted repair of islet tissue damage. Moreover, hUCMSCs@Ex-4 attenuated renal tissue lesions in T1DM mice. Applying bioinformatic analysis, the effects of hUCMSCs@Ex-4 were suggested to correlate with decreased abundance of pro-inflammatory intestinal bacteria and increased abundance of anti-inflammatory intestinal bacteria. CONCLUSION: Overall, the study indicated that hUCMSCs carrying exenatide might improve beneficial intestinal microflora abundance and promote islet tissue damage repair, thereby alleviating T1DM.

A comprehensive evaluation of pre- and post-processing sperm parameters for predicting successful pregnancy rate following intrauterine insemination with the husband's sperms.

BACKGROUND: To determine the predictive values of sperm parameters pre- and post-processing by density gradient centrifugation for clinical pregnancy rates (CPRs) following artificial insemination by husband (AIH) in infertile Chinese couples. METHODS: A total of 3,522 AIH cycles from 1,918 couples were retrospectively analyzed. The parameters were compared between the pregnant and non-pregnant groups and further between different etiological groups (Male-factor, Both-male-and-female-factor, and Other-factor). Multivariate logistic regression analysis was performed to create models for predicting the CPRs of each etiological group. RESULTS: The overall CPR was 13.3%. There were significant improvements for most sperm parameters after DGC. Multivariate logistic regression analysis indicated that, in overall AIH cases, the top parameters significantly influencing the CPR of AIH were pre-STR (OR = 1.037; P = 0.048) and post-VSL (OR = 1.036; P = 0.011). In the Male-factor Group, the top influencing parameters were pre-VCL (OR = 2.096; P = 0.008), pre-LIN (OR = 1.930; P = 0.002) and post-VSL (OR = 1.316; P = 0.023). In the Both-factor Group, the top influencing parameters were pre-VCL (OR = 1.451; P = 0.008) and post-motility (OR = 1.218; P = 0.049). In the Other-factor Group, the top influencing parameters were pre-VAP (OR = 1.715; P = 0.024), pre-STR (OR = 1.20; P = 0.011) and post-VSL (OR = 1.04; P = 0.017). Moreover, receiver operating characteristic analysis showed that the logistic regression models of the Male- and Both-factor Groups had greater powers for prognostic classification than those of other groups. CONCLUSIONS: This study demonstrated that some sperm parameters have a collinearity relationship in predicting the CPR following AIH. Moreover, the predictive capacity of a multivariate logistic regression model is better than those of individual parameters, especially for the Male- and Both-factor Groups. In these cases, pre-VCL is the common top influencing factor.

A comprehensive method to increase yield and narrow the yield gap of winter wheat for sustainable intensification.

BACKGROUND: The agricultural production system is facing increasing demand pressure and environmental pressure. Green and efficient production methods are urgently needed in order to further enhance the yield of winter wheat and reduce the negative impact on the environment. Here, we analyzed the potential yield and yield gap of winter wheat in Shandong Province of China from 1981 to 2009. Meanwhile, we specified the effects of sowing time, irrigation and fertilization scheme, and variety characteristics on winter wheat. RESULTS: In the past 29 years, the yield gap in most areas of Shandong has become smaller, because the actual yield has increased and the potential yield has changed little under the background of climate change. In addition, it is found that delaying sowing date is beneficial to increase yield by helping winter wheat avoid adverse climate conditions. Also, an irrigation amount of 240 mm and nitrogen application amount of 180-210 kg ha-1 are best to maintain high yield, high resource utilization rate and low environmental pollution in this area. These suggested levels are lower than those currently used by many local farmers. Wheat varieties with longer grain-filling period and photoperiod response, higher grain-filling rate and grain weight were more adaptable to climate change. CONCLUSION: Improving agronomic management measures can significantly increase the yield of winter wheat and narrow the yield gap. This study can provide valuable information for improving the production potential of winter wheat, and for reducing the damage of agricultural activities to the environment. © 2022 Society of Chemical Industry.

[Comprehensive genetic analysis in first or second trimester pregnancy loss using chromosomal microarray with single nucleotide polymorphism probes].

OBJECTIVE: To explore possible genetic causes associated with early pregnancy loss using chromosomal microarray analysis (CMA) with single nucleotide polymorphism (SNP) probes. METHODS: A retrospective review was performed by the CMA of samples from 961 patients who spontaneously aborted in our hospital before the 20th week of pregnancy. RESULTS: (1) The total chromosome abnormality rate in miscarriage samples was 54.44% (515/946), including single chromosome abnormality (39.53%), two chromosome abnormality (2.22%), multi-chromosome abnormality (0.42%), triploidy or hypertriploidy (4.86%), copy number variants (CNVs) in 41 cases (4.33%), regions of homozygosity (ROH, 0.74%), mosaic (2.22%) and chimera (0.11%). (2) CNV analysis of 41 cases showed that 85.36% were pathogenic and likely pathogenic, 12.20% were classified as clinical significance unknown and 2.44% were interpreted as likely benign; (3) Among the cases of ROH, 2 cases shown whole-genome homozygosity and 1 case had completely homozygous at chromosome 21. The homozygous regions in 2 cases were located at the end of the short arm of chromosome 16, suggesting the mechanism of ROH in such cases could be the result of isodisomy. CONCLUSION: Chromosome abnormality is an important genetic factor causing pregnancy loss. The application of CMA with SNP probes can indeed improve the detection rate of chromosome abnormalities and evaluate the risk of reproductive fertility in patients with pregnancy loss.

Pak2 reduction induces a failure of early embryonic development in mice.

BACKGROUND: The quality of the early embryo is vital to embryonic development and implantation. As a highly conserved serine/threonine kinase, p21-activated kinase 2 (Pak2) participates in diverse biologic processes, especially in cytoskeleton remodeling and cell apoptosis. In mice, Pak2 knock out and endothelial depletion of Pak2 showed embryonic lethality. However, the role of Pak2 in preimplantation embryos remains unelucidated. METHODS: In the present work, Pak2 was reduced using a specific small interfering RNA in early mouse embryos, validating the unique roles of Pak2 in spindle assembly and DNA repair during mice early embryonic development. We also employed immunoblotting, immunostaining, in vitro fertilization (IVF) and image quantification analyses to test the Pak2 knockdown on the embryonic development progression, spindle assembly, chromosome alignment, oxidative stress, DNA lesions and blastocyst cell apoptosis. Areas in chromatin with γH2AX were detected by immunofluorescence microscopy and serve as a biomarker of DNA damages. RESULTS: We found that Pak2 knockdown significantly reduced blastocyst formation of early embryos. In addition, Pak2 reduction led to dramatically increased abnormal spindle assembly and chromosomal aberrations in the embryos. We noted the overproduction of reactive oxygen species (ROS) with Pak2 knockdown in embryos. In response to DNA double strand breaks (DSBs), the histone protein H2AX is specifically phosphorylated at serine139 to generate γH2AX, which is used to quantitative DSBs. In this research, Pak2 knockdown also resulted in the accumulation of phosphorylated γH2AX, indicative of increased embryonic DNA damage. Commensurate with this, a significantly augmented rate of blastocyst cell apoptosis was detected in Pak2-KD embryos compared to their controls. CONCLUSIONS: Collectively, our data suggest that Pak2 may serve as an important regulator of spindle assembly and DNA repair, and thus participate in the development of early mouse embryos.

PEX-168 improves insulin resistance, inflammatory response and adipokines in simple obese mice: a mechanistic exploration.

BACKGROUND: Polyethylene glycol loxenatide (PEX-168) is a new antidiabetic drug; as such, there are not yet any reports on its weight loss effect. Therefore, this trial was designed to investigate the effect of PEX-168 on simple obese mice. METHODS: Thirty healthy male C57BL/6 mice were randomly selected and divided into a control group (NC) and an obesity model group. The high-fat diet-induced simple obesity mice were divided into a model control group (HF) and three intervention groups. The intervention groups were injected with different doses of PEX-168 intraperitoneally once a week for 12 weeks (low (LD), medium (MD) and high (HD)). Fasting blood glucose (FBG), body weight and food intake were measured from 1 to 12 weeks after PEX-168 injection. The serum insulin (INS), C-reactive protein (CRP), chemerin and omentin levels were measured after 12 weeks. RESULTS: Compared with the HF group, the low dose of PEX-168 reduced the body weight of the mice in a short period of time (8 weeks), and the mice in the MD and HD groups showed a significant decrease in body weight (P < 0.05). The low dose of PEX-168 could effectively improve the blood glucose and homeostasis model assessment of insulin resistance (Homa-IR) of the mice (FBG P < 0.05 INS, Homa-IR P < 0.001), but there was no significant difference between different doses (P > 0.05). CRP levels in the MD and HD groups were significantly improved (P < 0.05). The levels of serum chemerin and omentin in the intervention groups were also significantly improved (P < 0.01), but there was no significant difference between the different doses (P > 0.05). CONCLUSIONS: PEX-168 significantly reduced the body weight of simple obese mice and improved the insulin resistance. PEX-168 may regulate the expression of chemerin and omentin through its hypoglycaemic effect, and the weight-reducing effect of PEX-168 is unlikely to be the reason for the changes in both.

Stereoselective environmental fate of fosthiazate in soil and water-sediment microcosms.

The stereoselective fates of chiral pesticides in the environment has been reported in many studies. However, there is little data focused on the fate of chiral fosthiazate in the soil and aquatic ecosystems at chiral view. This study investigated the stereoselective fate of fosthiazate in the soil and aquatic ecosystems using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) and liquid chromatography tandem time-of-flight mass spectrometry (LC-TOF/MS/MS). Significant stereoselective degradation among four fosthiazate stereoisomers were found in both greenhouse soil and water-sediment microcosms. In greenhouse soil, (1R,3S)-fosthiazate degraded faster than other three stereoisomers with the half-life of 2.7 d. The fosthiazate stereisomers in the seawater-sediment microcosm degraded more rapidly than in the river water-sediment microcosm. However, (1S,3R)-fosthiazate and (1S,3S)-fosthiazate possessed shorter degradation half-lives than their enantiomers in both microcosms, with the half-lives ranging from 3.4 d to 15.8 d. Ten degradation products were identified in the water-sediment microcosms, and, six of them were reported for the first time. Oxidation and hydrolysis were confirmed as the main degradation pathways of fosthiazate in the water-sediment microcosms. Our results revealed that the (1R,3S)-fosthiazate and (1R,3R)-fosthiazate may cause more serious ecotoxicity due to the longer half-lives than the other two stereoisomers in environment.

Gliotoxin Is an Important Secondary Metabolite Involved in Suppression of Sclerotium rolfsii of Trichoderma virens T23.

Sclerotium rolfsii causes destructive soilborne disease in numerous plant species, and biological control may be a promising and sustainable approach for suppressing this widespread pathogen. In this study, the antagonistic effect against S. rolfsii of 10 Trichoderma strains was tested by the dual culture method, and a gliotoxin-producing strain, T. virens T23, was shown to be the most effective, inhibiting growth of S. rolfsii in vitro by 70.2%. To clarify the antagonistic mechanism and gliotoxin biosynthesis regulation of T23, a gliotoxin-deficient mutant was constructed via Agrobacterium tumefaciens-mediated gene knockout in vivo. As expected, disruption of the gene located in the putative gliotoxin biosynthesis gene cluster, gliI-T, resulted in gliotoxin deficiency and attenuation of the antagonistic effect against S. rolfsii, indicating that gliotoxin biosynthesis is regulated by gliI-T and that gliotoxin is an important antifungal metabolite of T23. Transmission electron microscopy revealed that gliotoxin treatment caused marked alterations of the hyphal cells of S. rolfsii depending on the drug concentration, whereby one of the prominent structural alterations was a reduction in the number and length of mitochondrial cristae. When S. rolfsii was exposed to 30 µg/ml of gliotoxin for 12 h, striking plasmolysis and ultrastructural changes were induced. The results demonstrated that gliotoxin is an important secondary metabolite of T. virens T23 in its antagonism against S. rolfsii.

Altered microRNAs in C3H10T1/2 cells induced by p.E95K mutant IHH signaling.

BACKGROUND: Indian Hedgehog (IHH), an important cell signaling protein, plays a key regulatory role in development of cartilage and chondrogenesis. Earlier studies have shown that heterozygous missense mutations in IHH gene may cause brachydactyly type A1 (BDA1), an autosomal dominant inheritance disease characterized by apparent shortness or absence of the middle phalanges of all digits. MicroRNAs (miRNAs) have been found to be significant post-transcriptional regulators of gene expression and significantly influence the process of bone-development. Therefore, it is possible that miRNAs are involved in the mechanism underlying the development of BDA1. However, the relationship between miRNAs and the pathogenesis of BDA1 remains unclear. METHODS: In this study, we used microarray-based miRNA profiling to investigate the role of miRNAs in BDA1 by characterization of differentially expressed miRNAs in C3H10T1/2 cell line induced by wild type (WT) and p.E95K mutant (MT) IHH signaling. RESULTS: Our results identified 6 differentially expressed miRNAs between WT and control (CT) group and 5 differentially expressed miRNAs between MT and CT groups. In particular, miR-135a-1-3p was found to be a significantly differentially expressed miRNA between WT and CT group. Results of dual-luciferase reporter gene experiment successfully discovered Hoxd10 was one of the target gene of miR-135a-1-3p. Additionally, our pathway analysis revealed that the targets of these miRNAs of interest were highly involved with Runx1/2, Notch and collagen-related pathways. CONCLUSIONS: Taken together, our findings provided important clue for future study of the process of miRNA-regulation in IHH signaling and novel insights into the regulatory role of miRNA in pathogenesis of BDA1.

Enantioseparation and stereoselective dissipation of the novel chiral fungicide pydiflumetofen by ultra-high-performance liquid chromatography tandem mass spectrometry.

Pydiflumetofen is a novel and efficient broad-spectrum chiral fungicide consisting of a pair of enantiomers. A simple and sensitive chiral analytical method was established to determine the enantiomers of this chiral fungicide in food and environmental samples by ultra-high-performance liquid chromatography tandem triple quadrupole mass spectrometry (UHPLC-MS/MS) using QuEChERS method coupled with octadecylsilane-dispersive solid-phase extraction (C18-dSPE) as extraction procedure. The specific optical rotation and the absolute configuration of the enantiomers were identified by polarimetry and electronic circular dichroism (ECD). The elution order of the pydiflumetofen enantiomers on Lux Cellulose-2 was S-(-)-pydiflumetofen and R-(+)-pydiflumetofen. The average recoveries of eleven matrices ranged from 71.3% to 107.4%. The intraday relative standard deviations (RSDs) were less than 11.8%, and the interday RSDs were less than 12.6% for the two enantiomers. Stereoselective dissipation in pakchoi and soil were observed: S-(-)-pydiflumetofen was degraded faster than R-(+)-pydiflumetofen in pakchoi, causing the enantiomer fraction (EF) of the enantiomers to change from 0.50 to 0.42 in 7 days. However, R-(+)-pydiflumetofen was degraded faster than S-(-)-pydiflumetofen in soil, causing the EF of the enantiomers to change from 0.49 to 0.52 in 21 days. This study provides a method for monitoring pydiflumetofen enantiomer residues, which is crucial for improving risk assessments and the development of chiral pesticides.

A Rare Case of Hb H Disease and Systemic Lupus Erythematosus.

Anemia is common in patients with systemic lupus erythematosus (SLE). The association between thalassemia and SLE is rare. In this study, we report the first patient who was found to have a severe hemolytic anemia caused by combination of SLE and Hb H disease. The patient had a more severe presentation in the hematological system. Our case indicates that for a patient who was diagnosed with SLE and developed deterioration in her hematological cell lines, investigation of other possible coexisting causes would be warranted.

[Research progress of iron metabolism in phenotype modification of ß-thalassemia].

ß-thalassemia is a type of inherited hemolytic anemia caused by decreased globin production due to defect of the HBB gene. The pathogenesis of the disease is imbalance of α/ß globin chains. The excess of α-globin chains will form hemichromes which can damage red blood cell membranes and lead to hemolysis, ineffective erythropoiesis, and secondary iron overload. Iron overload in turn can cause complications such as growth retardation, liver cirrhosis, cardiac insufficiency, and aggravate the disease phenotype. In recent decades, genes participating in iron metabolism have been discovered, and the mechanism of iron metabolism in the development of thalassemia has gradually been elucidated. Subsequently, by manipulating the expression of key genes in iron metabolism such as hepcidin and transferrin receptor, researchers have revealed that iron restriction can improve ineffective hematopoiesis and iron overload, which may provide a potential approach for the treatment of thalassemia. This article reviews the progress of research on iron metabolism-related genes and related pathways in ß-thalassemia.

[Clinical practice guidelines for the diagnosis of regions of homozygosity and uniparental disomy].

The overall prevalence of uniparental disomy (UPD) across all chromosomes was estimated to be around one birth in 2000. To date, more than 4170 UPD cases have been registered. UPD for chromosomes 6, 7, 11, 14, 15, and 20 can result in clinically recognizable imprinting disorders due to abnormal levels of imprinted gene expression. For other chromosomes, the clinical consequences associated with UPD are not apparent, unless when a recessive genetic disorder is unmasked by UPD or regions of homozygosity (ROH). A clinical practice guideline will assist in strengthening the precise analysis and interpretation of the clinical significance of ROH/UPD. This guideline summarizes the conception, mechanism and clinical consequences of ROH/UPD, as well as the principles for data analysis, with an aim to standardize the clinical application and data interpretation.