An enzyme that selectively S-nitrosylates proteins to regulate insulin signaling.

Acyl-coenzyme A (acyl-CoA) species are cofactors for numerous enzymes that acylate thousands of proteins. Here, we describe an enzyme that uses S-nitroso-CoA (SNO-CoA) as its cofactor to S-nitrosylate multiple proteins (SNO-CoA-assisted nitrosylase, SCAN). Separate domains in SCAN mediate SNO-CoA and substrate binding, allowing SCAN to selectively catalyze SNO transfer from SNO-CoA to SCAN to multiple protein targets, including the insulin receptor (INSR) and insulin receptor substrate 1 (IRS1). Insulin-stimulated S-nitrosylation of INSR/IRS1 by SCAN reduces insulin signaling physiologically, whereas increased SCAN activity in obesity causes INSR/IRS1 hypernitrosylation and insulin resistance. SCAN-deficient mice are thus protected from diabetes. In human skeletal muscle and adipose tissue, SCAN expression increases with body mass index and correlates with INSR S-nitrosylation. S-nitrosylation by SCAN/SNO-CoA thus defines a new enzyme class, a unique mode of receptor tyrosine kinase regulation, and a revised paradigm for NO function in physiology and disease.

Breaking the symmetry of cell contractility drives tubulogenesis via CXCL1 polarization.

The intricate interplay between biomechanical and biochemical pathways in modulating morphogenesis is an interesting research topic. How biomechanical force regulates epithelial cell tubulogenesis remains poorly understood. Here, we established a model of tubulogenesis by culturing renal proximal tubular epithelial cells on a collagen gel while manipulating contractile force. Epithelial cells were dynamically self-organized into tubule-like structures by augmentation of cell protrusions and cell-cell association. Reduction and asymmetric distribution of phosphorylated myosin light chain 2, the actomyosin contractility, in cells grown on soft matrix preceded tube connection. Notably, reducing matrix stiffness via sonication of collagen fibrils and inhibiting actomyosin contractility with blebbistatin promoted tubulogenesis, whereas inhibition of cytoskeleton polymerization suppressed it. CXC chemokine ligand 1 (CXCL1) expression was transcriptionally upregulated in cells undergoing tubulogenesis. Additionally, inhibiting actomyosin contractility facilitated CXCL1 polarization and cell protrusions preceding tube formation. Conversely, inhibiting the CXCL1-CXC receptor 1 pathway hindered cell protrusions and tubulogenesis. Mechanical property asymmetry with cell-collagen fibril interaction patterns at cell protrusions and along the tube structure supported the association of anisotropic contraction with tube formation. Furthermore, suppressing the mechanosensing machinery of integrin subunit beta 1 reduced CXCL1 expression, collagen remodeling, and impaired tubulogenesis. In summary, symmetry breaking of cell contractility on a soft collagen gel promotes CXCL1 polarization at cell protrusions which in turn facilitates cell-cell association and thus tubule connection.

Author Correction: Metabolic reprogramming by the S-nitroso-CoA reductase system protects against kidney injury.

Change history: In Fig. 1j of this Letter, one data point was inadvertently omitted from the graph for the acute kidney injury (AKI), double knockout (-/-), S-nitrosothiol (SNO) condition at a nitrosylation level of 25.9 pmol mg-1 and the statistical significance given of P = 0.0221 was determined by Fisher's test instead of P = 0.0032 determined by Tukey's test (with normalization for test-day instrument baseline). Figure 1 and its Source Data have been corrected online.

Metabolic reprogramming by the S-nitroso-CoA reductase system protects against kidney injury.

Endothelial nitric oxide synthase (eNOS) is protective against kidney injury, but the molecular mechanisms of this protection are poorly understood1,2. Nitric oxide-based cellular signalling is generally mediated by protein S-nitrosylation, the oxidative modification of Cys residues to form S-nitrosothiols (SNOs). S-nitrosylation regulates proteins in all functional classes, and is controlled by enzymatic machinery that includes S-nitrosylases and denitrosylases, which add and remove SNO from proteins, respectively3,4. In Saccharomyces cerevisiae, the classic metabolic intermediate co-enzyme A (CoA) serves as an endogenous source of SNOs through its conjugation with nitric oxide to form S-nitroso-CoA (SNO-CoA), and S-nitrosylation of proteins by SNO-CoA is governed by its cognate denitrosylase, SNO-CoA reductase (SCoR)5. Mammals possess a functional homologue of yeast SCoR, an aldo-keto reductase family member (AKR1A1)5 with an unknown physiological role. Here we report that the SNO-CoA-AKR1A1 system is highly expressed in renal proximal tubules, where it transduces the activity of eNOS in reprogramming intermediary metabolism, thereby protecting kidneys against acute kidney injury. Specifically, deletion of Akr1a1 in mice to reduce SCoR activity increased protein S-nitrosylation, protected against acute kidney injury and improved survival, whereas this protection was lost when Enos (also known as Nos3) was also deleted. Metabolic profiling coupled with unbiased mass spectrometry-based SNO-protein identification revealed that protection by the SNO-CoA-SCoR system is mediated by inhibitory S-nitrosylation of pyruvate kinase M2 (PKM2) through a novel locus of regulation, thereby balancing fuel utilization (through glycolysis) with redox protection (through the pentose phosphate shunt). Targeted deletion of PKM2 from mouse proximal tubules recapitulated precisely the protective and mechanistic effects of S-nitrosylation in Akr1a1-/- mice, whereas Cys-mutant PKM2, which is refractory to S-nitrosylation, negated SNO-CoA bioactivity. Our results identify a physiological function of the SNO-CoA-SCoR system in mammals, describe new regulation of renal metabolism and of PKM2 in differentiated tissues, and offer a novel perspective on kidney injury with therapeutic implications.

TEM1/endosialin/CD248 promotes pathologic scarring and TGF-ß activity through its receptor stability in dermal fibroblasts.

BACKGROUND: Pathologic scars, including keloids and hypertrophic scars, represent a common form of exaggerated cutaneous scarring that is difficult to prevent or treat effectively. Additionally, the pathobiology of pathologic scars remains poorly understood. We aim at investigating the impact of TEM1 (also known as endosialin or CD248), which is a glycosylated type I transmembrane protein, on development of pathologic scars. METHODS: To investigate the expression of TEM1, we utilized immunofluorescence staining, Western blotting, and single-cell RNA-sequencing (scRNA-seq) techniques. We conducted in vitro cell culture experiments and an in vivo stretch-induced scar mouse model to study the involvement of TEM1 in TGF-ß-mediated responses in pathologic scars. RESULTS: The levels of the protein TEM1 are elevated in both hypertrophic scars and keloids in comparison to normal skin. A re-analysis of scRNA-seq datasets reveals that a major profibrotic subpopulation of keloid and hypertrophic scar fibroblasts greatly expresses TEM1, with expression increasing during fibroblast activation. TEM1 promotes activation, proliferation, and ECM production in human dermal fibroblasts by enhancing TGF-ß1 signaling through binding with and stabilizing TGF-ß receptors. Global deletion of Tem1 markedly reduces the amount of ECM synthesis and inflammation in a scar in a mouse model of stretch-induced pathologic scarring. The intralesional administration of ontuxizumab, a humanized IgG monoclonal antibody targeting TEM1, significantly decreased both the size and collagen density of keloids. CONCLUSIONS: Our data indicate that TEM1 plays a role in pathologic scarring, with its synergistic effect on the TGF-ß signaling contributing to dermal fibroblast activation. Targeting TEM1 may represent a novel therapeutic approach in reducing the morbidity of pathologic scars.

BRAF-V600E mutations in plasma and peripheral blood mononuclear cells correlate with prognosis of pediatric Langerhans cell histiocytosis treated with first-line therapy.

BACKGROUND: The clinical relevance of BRAF-V600E alleles in peripheral blood mononuclear cells (PBMCs) and the prognostic impact of the mutants in cell-free (cf) and PBMC DNAs of Langerhans cell histiocytosis (LCH) have not been fully clarified in pediatric LCH. METHODS: We retrospectively determined the levels of BRAF-V600E mutation in paired plasma and PBMC samples at the time of diagnosis of LCH. Subsequently, we performed a separate or combined analysis of the clinical and prognostic impact of the mutants. RESULTS: We assessed BRAF-V600E mutation in peripheral blood from 94 patients of childhood LCH. Our data showed that cfBRAF-V600E was related to young age, multiple-system (MS) disease, involvements of organs with high risk, increased risk of relapse, and worse progression-free survival (PFS) of patients. We also observed that the presence of BRAF-V600E in PBMCs at baseline was significantly associated with MS LCH with risk organ involvement, younger age, and disease progression or relapse. The coexisting of plasma(+)/PBMC(+) identified 36.2% of the patients with the worst outcome, and the hazard ratio was more significant than either of the two alone or neither, indicating that combined analysis of the mutation in plasma and PBMCs was more accurate to predict relapse than evaluation of either one. CONCLUSIONS: Concurrent assessment of BRAF-V600E mutation in plasma and PBMCs significantly impacted the prognosis of children with LCH. Further prospective studies with larger cohorts need to validate the results of this study.

Neural decoding dissociates perceptual grouping between proximity and similarity in visual perception.

Unlike single grouping principle, cognitive neural mechanism underlying the dissociation across two or more grouping principles is still unclear. In this study, a dimotif lattice paradigm that can adjust the strength of one grouping principle was used to inspect how, when, and where the processing of two grouping principles (proximity and similarity) were carried out in human brain. Our psychophysical findings demonstrated that similarity grouping effect was enhanced with reduced proximity effect when the grouping cues of proximity and similarity were presented simultaneously. Meanwhile, EEG decoding was performed to reveal the specific cognitive patterns involved in each principle by using time-resolved MVPA. More importantly, the onsets of dissociation between 2 grouping principles coincided within 3 time windows: the early-stage proximity-defined local visual element arrangement in middle occipital cortex, the middle-stage processing for feature selection modulating low-level visual cortex such as inferior occipital cortex and fusiform cortex, and the high-level cognitive integration to make decisions for specific grouping preference in the parietal areas. In addition, it was discovered that the brain responses were highly correlated with behavioral grouping. Therefore, our study provides direct evidence for a link between the human perceptual space of grouping decision-making and neural space of brain activation patterns.

Analyzing the correlation between quinolone-resistant Escherichia coli resistance rates and climate factors: A comprehensive analysis across 31 Chinese provinces.

BACKGROUND: The increasing problem of bacterial resistance, particularly with quinolone-resistant Escherichia coli (QnR eco) poses a serious global health issue. METHODS: We collected data on QnR eco resistance rates and detection frequencies from 2014 to 2021 via the China Antimicrobial Resistance Surveillance System, complemented by meteorological and socioeconomic data from the China Statistical Yearbook and the China Meteorological Data Service Centre (CMDC). Comprehensive nonparametric testing and multivariate regression models were used in the analysis. RESULT: Our analysis revealed significant regional differences in QnR eco resistance and detection rates across China. Along the Hu Huanyong Line, resistance rates varied markedly: 49.35 in the northwest, 54.40 on the line, and 52.30 in the southeast (P = 0.001). Detection rates also showed significant geographical variation, with notable differences between regions (P < 0.001). Climate types influenced these rates, with significant variability observed across different climates (P < 0.001). Our predictive model for resistance rates, integrating climate and healthcare factors, explained 64.1% of the variance (adjusted R-squared = 0.641). For detection rates, the model accounted for 19.2% of the variance, highlighting the impact of environmental and healthcare influences. CONCLUSION: The study found higher resistance rates in warmer, monsoon climates and areas with more public health facilities, but lower rates in cooler, mountainous, or continental climates with more rainfall. This highlights the strong impact of climate on antibiotic resistance. Meanwhile, the predictive model effectively forecasts these resistance rates using China's diverse climate data. This is crucial for public health strategies and helps policymakers and healthcare practitioners tailor their approaches to antibiotic resistance based on local environmental conditions. These insights emphasize the importance of considering regional climates in managing antibiotic resistance.

TMEM151A variants associated with paroxysmal kinesigenic dyskinesia.

TMEM151A, located at 11q13.2 and encoding transmembrane protein 151A, was recently reported as causative for autosomal dominant paroxysmal kinesigenic dyskinesia (PKD). Here, through comprehensive analysis of sporadic and familial cases, we expand the clinical and mutation spectrum of PKD. In doing so, we clarify the clinical and genetic features of Chinese PKD patients harboring TMEM151A variants and further explore the relationship between TMEM151A mutations and PKD. Whole exome sequencing was performed on 26 sporadic PKD patients and nine familial PKD pedigrees without PRRT2 variants. Quantitative real-time PCR was used to assess the gene expression of frameshift mutant TMEM151A in a PKD patient. TMEM151A variants reported to date were reviewed. Four TMEM151A variants were detected in four unrelated families with 12 individuals, including a frameshift mutation [c.606_607insA (p.Val203fs)], two missense mutations [c.166G > A (p.Gly56Arg) and c.791T > C (p.Val264Ala)], and a non-pathogenic variant [c.994G > A (p.Gly332Arg)]. The monoallelic frameshift mutation [c.606_607insA (p.Val203fs)] may cause TMEM151A mRNA decay, suggesting a potential pathogenic mechanism of haploinsufficiency. Patients with TMEM151A variants had short-duration attacks and presented with dystonia. Our study provides a detailed clinical description of PKD patients with TMEM151A mutations and reports a new disease-causing mutation, expanding the known phenotypes caused by TMEM151A mutations and providing further detail about the pathoetiology of PKD.

Striatonigrostriatal connectivity-based cross-species parcellation of human and macaque substantia nigra.

Anatomical and functional heterogeneous substantia nigra (SN) has been extensively studied in humans and animals like rhesus monkeys given its crucial role in modulating a broad range of behaviors. Increasingly important cross-species research of SN may require connectionally homogeneous and homologous subregions of SN as objective and stable starting points from which the evolutionary characteristics of brain could be inspected. However, existing atlases of SN were all inaccurate mappings as a cross-species connectome atlas due to inadequate homology constraint during their constructions, and arbitrary paired use of these atlases might cause unreliable findings. In this study, a reliable blind-source cross-species parcellation of SN was developed based on the following rationale: striatonigrostriatal circuits form major structure of nigral connectivity; different nigral components have unique striatonigrostriatal connectivity; and inter-species corresponding human and macaque nigral components have similar striatonigrostriatal connectivity. Specifically, all voxels in human and macaque SN were grouped together and then classified based on inter-species identically characterized striatonigrostriatal connectivity attributes. Our results delineated a pars compacta-pars reticulate-like parcellation and further demonstrated its reliability by illustrating best-matched whole-brain structural and functional connectivity profiles of inter-species corresponding nigral subregions. Detailed inter-species and inter-regional differences in multi-aspect connectivities of these nigral subregions were inspected. It is expected that this cross-species connectome atlas of SN can offer biologically reliable cornerstones and important information to facilitate future cross-species research.

Metabolic activation of tyrosine kinase inhibitors: recent advance and further clinical practice.

At present, receptor tyrosine kinase signaling-related pathways have been successfully mediated to inhibit tumor proliferation and promote anti-angiogenesis effects for cancer therapy. Tyrosine kinase inhibitors (TKIs), a group of novel chemotherapeutic agents, have been applied to treat diverse malignant tumors effectively. However, the latent toxic and side effects of TKIs, such as hepatotoxicity and cardiotoxicity, limit their use in clinical practice. Metabolic activation has the potential to lead to toxic effects. Numerous TKIs have been demonstrated to be transformed into chemically reactive/potentially toxic metabolites following cytochrome P450-catalyzed activation, which causes severe adverse reactions, including hepatotoxicity, cardiotoxicity, skin toxicity, immune injury, mitochondria injury, and cytochrome P450 inactivation. However, the precise mechanisms of how these chemically reactive/potentially toxic species induce toxicity remain poorly understood. In addition, we present our viewpoints that regulating the production of reactive metabolites may decrease the toxicity of TKIs. Exploring this topic will improve understanding of metabolic activation and its underlying mechanisms, promoting the rational use of TKIs. This review summarizes the updated evidence concerning the reactive metabolites of TKIs and the associated toxicities. This paper provides novel insight into the safe use of TKIs and the prevention and treatment of multiple TKIs adverse effects in clinical practice.

Constant p.L424H Mutation in GTF2I in Micronodular Thymomas With Lymphoid Stroma: Evidence Supporting Close Relationship With Type A and AB Thymomas.

Micronodular thymoma with lymphoid stroma is a rare thymic neoplasm characterized by discrete nodules of epithelial tumor cells separated by abundant lymphoid stroma. The genetic features of micronodular thymoma with lymphoid stroma remain largely unexplored. Owing to the interference of abundant intratumoral, nonneoplastic lymphoid cells, a highly sensitive approach is necessary to study genetic changes in these tumors. In this study, we used a highly sensitive next-generation sequencing assay using the molecular barcoding Ion AmpliSeq HD technology to study the most commonly mutated genes in thymomas, including GTF2I, HRAS, NRAS, KRAS, and TP53. A total of 12 cases of micronodular thymomas with lymphoid stroma were tested, and 2 cases also had areas of type A thymoma in their tumor bed. Two micronodular thymic carcinomas with lymphoid stroma, a histological mimic of micronodular thymoma, were also included for comparison. Recurrent p.L424H mutations in GTF2I were found in all the cases of micronodular thymoma with lymphoid stroma but not in the cases of micronodular thymic carcinomas. In addition, 3 cases of micronodular thymoma with lymphoid stroma also had concomitant HRAS and/or KRAS mutations. Our study showed that p.L424H mutations in GTF2I is a constant genetic feature of micronodular thymoma with lymphoid stroma. This finding strongly suggests that micronodular thymoma with lymphoid stroma is closely related to type A and AB thymomas because they all share p.L424H mutations in GTF2I.

SARS-CoV-2 NSP13 interacts with host IRF3, blocking antiviral immune responses.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses an unprecedented threat to human health since late 2019. Notably, the progression of the disease is associated with impaired antiviral interferon (IFN) responses. Although multiple viral proteins were identified as potential IFN antagonists, the underlying molecular mechanisms remain to be fully elucidated. In this study, we firstly demonstrate that SARS-CoV-2 NSP13 protein robustly antagonizes IFN response induced by the constitutively active form of transcription factor IRF3 (IRF3/5D). This induction of IFN response by IRF3/5D is independent of the upstream kinase, TBK1, a previously reported NSP13 target, thus indicating that NSP13 can act at the level of IRF3 to antagonize IFN production. Consistently, NSP13 exhibits a specific, TBK1-independent interaction with IRF3, which, moreover, is much stronger than that of NSP13 with TBK1. Furthermore, the NSP13-IRF3 interaction was shown to occur between the NSP13 1B domain and IRF3 IRF association domain (IAD). In agreement with the strong targeting of IRF3 by NSP13, we then found that NSP13 blocks IRF3-directed signal transduction and antiviral gene expression, counteracting IRF3-driven anti-SARS-CoV-2 activity. These data suggest that IRF3 is likely to be a major target of NSP13 in antagonizing antiviral IFN responses and provide new insights into the SARS-CoV-2-host interactions that lead to viral immune evasion.

Prevalence of metabolic syndrome and its components in Chinese women with premature ovarian insufficiency.

OBJECTIVES: To assess the prevalence of metabolic syndrome (MetS) and its components in Chinese women with premature ovarian insufficiency (POI) and to explore the metabolic profile of Chinese women with POI. METHODS: 118 POI women aged 20-38 years and 151 age-and-BMI-matched control women were recruited. Measurements included body height, weight, waist circumference (WC), hip circumference (HC), blood pressure, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG) and fasting insulin (FINS). Prevalence and components of MetS and metabolic indices were compared between the two groups. RESULTS: The prevalence of MetS in POI women and age-and-BMI-matched control women was 16.9% and 11.3%, respectively, which was not significantly different (p > .05). The prevalence of hypertriglyceridemia and high fasting glucose was significantly higher in POI than control (17.8% vs. 9.3%, p = .039; 16.9% vs. 6.6%, p = .008), without significant differences in the prevalence of other components of MetS (p > .05). The levels of TG, FINS, and HOMA-IR in POI were significantly higher than in control (p < .05) but without significant differences in WC, WHR, SBP, DBP, TC, HDL-C, LDL-C, and FPG (p > .05). HOMA-IR was positively correlated with WC, DBP, TG, and FPG and negatively correlated with HDL-C in both POI women and control (p < .05). CONCLUSIONS: POI women presented with more unfavorable cardiovascular risk factors (higher prevalence of hypertriglyceridemia and high fasting glucose; higher TG, FINS, and HOMA-IR). So, women diagnosed with POI should always be covered with special care of metabolic profile.

Prevalence of diminished ovarian reserve in Chinese women with follicular cysts and menstrual disorders.

OBJECTIVES: To assess the prevalence of diminished ovarian reserve (DOR) in Chinese women with follicular cysts and menstrual disorders and relationship to hormonal markers. METHODS: 117 women with follicular cysts and menstrual disorders, aged 24 ∼ 53 (39.19 ± 6.61) years; measurements of height, weight, follicle-stimulating hormone (FSH), luteinizing hormone (LH), E2, progesterone (Po), prolactin (PRL), total testosterone, AMH, follicular cyst diameter, endometrial thickness. Three age groups were compared: 1) 21 ∼ 30 years, 2) 30 ∼ 40 years, 3) > 40 years. RESULTS: Total prevalence of DOR 86.3%, in the groups 50%, 81.6%, and 98.4%, in group-3 significantly higher than in group-1 and 2. 34.2% of the 117 patients complained of cessation of regular menstruations or amenorrhea, 65.8% of abnormal uterine bleeding. Follicular cysts disappeard in cycle-1 for 98 (83.8%) and in cycle-2 for 117 (100%) patients. AMH decreased with age, significantly different between the three groups. Total testosterone in group-1 and 2 was significantly higher than in group-3. In total AMH had a negative correlation with age and E2 (p < 0.01) and positive correlation with total testosterone (p < 0.05). CONCLUSIONS: Assessing ovarian reserve with follicular cysts and menstrual disorders is important because often pointing to DOR. The overall prevalence of DOR was high; even young women (<40 years) with follicular cysts and menstrual disorders had a low level of AMH. So AMH can be used as a marker to define DOR with higher sensitivity than other markers like FSH and E2. Primarily, these results only apply to Chinese women and should be confirmed in further studies.

Complications and radiographic changes after implantation of interspinous process devices: average eight-year follow-up.

PURPOSE: This study aims to evaluate complications, clinical outcomes, and radiographic results following Coflex implantation. METHODS: We retrospectively studied 66 patients who had decompressive surgery combined with Coflex implantation to treat lumbar spinal stenosis. All imaging data were collected and examined for imaging changes. Clinical outcomes, included Oswestry Disability Index (ODI), back and leg visual analog scale (VAS) scores, were evaluated before surgery, six months after surgery and at the last follow-up. The number of complications occurring after five years of follow-up was counted. All reoperation cases were meticulously recorded. RESULTS: 66 patients were followed up for 5-14 years. The VAS and ODI scores were significantly improved compared with baseline. Heterotopic Ossification (HO) was detectable in 59 (89.4%). 26 (39.4%) patients had osteolysis at the contact site of Coflex with the spinous process. Coflex loosening was detected in 39 (60%) patients. Spinous process anastomosis was found in 34 (51.5%) patients. There was a statistically significant difference in the VAS score of back pain between patients with and without spinous process anastomosis. Nine cases of lumbar spinal restenosis were observed, and prosthesis fracture was observed in one case. CONCLUSION: Our study identified various imaging changes after Coflex implantation, and majority of them did not affect clinical outcomes. The majority of patients had HO, but osteolysis and Coflex loosening were relatively rare. The VAS score for back pain of these patients was higher if they have spinous process anastomosis. After five-year follow-up, we found lumbar spinal restenosis and prosthesis fracture cases.

A novel compound heterozygous mutation in TUBB8 causing early embryonic developmental arrest.

PURPOSE: Mutations in the ß-tubulin isotype, TUBB8, can cause female infertility. Although several mutations of TUBB8 have been reported, the full spectrum for guiding genetics counseling still needs to be further explored. Here, we sought to identify novel variants in TUBB8 and their phenotypic effects on microtubule network structure in vitro. METHODS: Whole-exome sequence analysis was performed in two families with infertility to detect pathogenic variants, with validation by Sanger sequencing. All gene variants and protein structures were predicted in silico. Cells were transfected with wild-type and mutants, and immunofluorescence analysis was performed to visualize microtubule network changes. RESULTS: We detected a novel compound heterozygous mutation, c.915_916delCC (p.Arg306Serfs*21) and c.82C > T (p.His28Tyr), and a benign heterozygous variant c.1286C > T (p.Thr429Met) in TUBB8 in the two families. Female patients with p.Arg306Serfs*21 and p.His28Tyr were infertile with early embryonic developmental arrest. The female patient with p.Thr429Met gave birth to a healthy baby in the second in vitro fertilization frozen embryo transfer cycle. The p.Arg306Serfs*21 mutation was predicted to cause large structural alteration in the TUBB8 protein and was confirmed to produce a truncated and trace protein by western blot analysis. Immunofluorescence analysis of transfected HeLa cells showed that p.Arg306Serfs*21 significantly disrupted microtubule structure. CONCLUSIONS: Our findings expand the known mutational spectrum of TUBB8 associated with early embryonic developmental arrest and female infertility.

Cervical elastography: finding a novel predictor for improving the prediction of preterm birth in uncomplicated twin pregnancies.

OBJECTIVE: This study set out to investigate a novel ultrasound parameter using cervical elastosonography for improving the prediction of spontaneous preterm birth (sPTB) in twin pregnancies. STUDY DESIGN: The study was comprised of 106 twin pregnancies from October 2020 to January 2022 in Beijing Obstetrics and Gynecology Hospital. They were divided into two groups according to gestational age (GA) at delivery (delivery < 35 weeks and delivery ≥ 35 weeks). There were five elastographic parameters: Elasticity Contrast Index (ECI), Cervical Hardness Ratio (CHR), Closed Internal cervical ostium Strain rate (CIS); External cervical ostium strain rate (ES), CIS/ES ratio and Cervical Length (CL). All of the clinical and ultrasonic indicators with P < 0.1 were considered candidate indicators via univariate logistic regression. Based on the extracted unified combination of clinical indicators, the combinations of permutation with the candidate ultrasound indicators were performed step by step in multivariable logistic regression. The best ultrasound indicator with the lowest Akaike Information Criterion (AIC) and the highest Areas Under the receiver operating characteristic Curve (AUC) was chosen for establishing the prediction score. RESULTS: Over 30% (36/106) of those who delivered before 35 weeks gestation. There were distinct differences in the clinical characteristics and cervical elastography parameters between the two groups. Seven major clinical variables were identified as a unified clinical indicator. CISmin as the best ultrasound elastography predictor indicated the lowest AIC and the highest AUC and outperformed alternative indicators significantly in the prediction of delivery before 35 weeks of gestation. Unfortunately, CLmin which was commonly used in clinical practice ranked far from all of the cervical elastography parameters and presented the highest AIC and the lowest AUC. A preliminary scoring rule was established and the ability to predict the risk of sPTB in twin pregnancies was improved (Accuracy: 0.896 vs 0.877; AIC: 81.494 vs 91.698; AUC: 0.923 vs 0.906). CONCLUSIONS: The cervical elastosonography predictor such as CISmin might be a more useful indicator applied for enhancing the ability in predicting twin pregnancies preterm birth than CL. Furthermore, there would be more benefits for advancing clinical decision-making in actual clinical practice by using cervical elastosonography in the near future.

Chondrocyte Thrombomodulin Protects against Osteoarthritis.

Osteoarthritis (OA) is a prevalent form of arthritis that affects over 32.5 million adults worldwide, causing significant cartilage damage and disability. Unfortunately, there are currently no effective treatments for OA, highlighting the need for novel therapeutic approaches. Thrombomodulin (TM), a glycoprotein expressed by chondrocytes and other cell types, has an unknown role in OA. Here, we investigated the function of TM in chondrocytes and OA using various methods, including recombinant TM (rTM), transgenic mice lacking the TM lectin-like domain (TMLeD/LeD), and a microRNA (miRNA) antagomir that increased TM expression. Results showed that chondrocyte-expressed TM and soluble TM [sTM, like recombinant TM domain 1 to 3 (rTMD123)] enhanced cell growth and migration, blocked interleukin-1ß (IL-1ß)-mediated signaling and protected against knee function and bone integrity loss in an anterior cruciate ligament transection (ACLT)-induced mouse model of OA. Conversely, TMLeD/LeD mice exhibited accelerated knee function loss, while treatment with rTMD123 protected against cartilage loss even one-week post-surgery. The administration of an miRNA antagomir (miR-up-TM) also increased TM expression and protected against cartilage damage in the OA model. These findings suggested that chondrocyte TM plays a crucial role in counteracting OA, and miR-up-TM may represent a promising therapeutic approach to protect against cartilage-related disorders.

Absence of the lectin-like domain of thrombomodulin reduces HSV-1 lethality of mice with increased microglia responses.

BACKGROUND: Herpes simplex virus 1 (HSV-1) can induce fatal encephalitis. Cellular factors regulate the host immunity to affect the severity of HSV-1 encephalitis. Recent reports focus on the significance of thrombomodulin (TM), especially the domain 1, lectin-like domain (TM-LeD), which modulates the immune responses to bacterial infections and toxins and various diseases in murine models. Few studies have investigated the importance of TM-LeD in viral infections, which are also regulated by the host immunity. METHODS: In vivo studies comparing wild-type and TM-LeD knockout mice were performed to determine the role of TM-LeD on HSV-1 lethality. In vitro studies using brain microglia cultured from mice or a human microglia cell line to investigate whether and how TM-LeD affects microglia to reduce HSV-1 replication in brain neurons cultured from mice or in a human neuronal cell line. RESULTS: Absence of TM-LeD decreased the mortality, tissue viral loads, and brain neuron apoptosis of HSV-1-infected mice with increases in the number, proliferation, and phagocytic activity of brain microglia. Moreover, TM-LeD deficiency enhanced the phagocytic activity of brain microglia cultured from mice or of a human microglia cell line. Co-culture of mouse primary brain microglia and neurons or human microglia and neuronal cell lines revealed that TM-LeD deficiency augmented the capacity of microglia to reduce HSV-1 replication in neurons. CONCLUSIONS: Overall, TM-LeD suppresses microglia responses to enhance HSV-1 infection.