HapX-mediated H2B deub1 and SreA-mediated H2A.Z deposition coordinate in fungal iron resistance.

Plant pathogens are challenged by host-derived iron starvation or excess during infection, but the mechanism through which pathogens counteract iron stress is unclear. Here, we found that Fusarium graminearum encounters iron excess during the colonization of wheat heads. Deletion of heme activator protein X (FgHapX), siderophore transcription factor A (FgSreA) or both attenuated virulence. Further, we found that FgHapX activates iron storage under iron excess by promoting histone H2B deubiquitination (H2B deub1) at the promoter of the responsible gene. Meanwhile, FgSreA is shown to inhibit genes mediating iron acquisition during iron excess by facilitating the deposition of histone variant H2A.Z and histone 3 lysine 27 trimethylation (H3K27 me3) at the first nucleosome after the transcription start site. In addition, the monothiol glutaredoxin FgGrx4 is responsible for iron sensing and control of the transcriptional activity of FgHapX and FgSreA via modulation of their enrichment at target genes and recruitment of epigenetic regulators, respectively. Taken together, our findings elucidated the molecular mechanisms for adaptation to iron excess mediated by FgHapX and FgSreA during infection in F. graminearum and provide novel insights into regulation of iron homeostasis at the chromatin level in eukaryotes.

Monocyte-derived SDF1 supports optic nerve regeneration and alters retinal ganglion cells' response to Pten deletion.

Although mammalian retinal ganglion cells (RGCs) normally cannot regenerate axons nor survive after optic nerve injury, this failure is partially reversed by inducing sterile inflammation in the eye. Infiltrative myeloid cells express the axogenic protein oncomodulin (Ocm) but additional, as-yet-unidentified, factors are also required. We show here that infiltrative macrophages express stromal cell­derived factor 1 (SDF1, CXCL12), which plays a central role in this regard. Among many growth factors tested in culture, only SDF1 enhances Ocm activity, an effect mediated through intracellular cyclic AMP (cAMP) elevation and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) activation. SDF1 deficiency in myeloid cells (CXCL12flx/flxLysM-Cre−/+ mice) or deletion of the SDF1 receptor CXCR4 in RGCs (intraocular AAV2-Cre in CXCR4flx/flx mice) or SDF1 antagonist AMD3100 greatly suppresses inflammation-induced regeneration and decreases RGC survival to baseline levels. Conversely, SDF1 induces optic nerve regeneration and RGC survival, and, when combined with Ocm/cAMP, SDF1 increases axon regeneration to levels similar to those induced by intraocular inflammation. In contrast to deletion of phosphatase and tensin homolog (Pten), which promotes regeneration selectively from αRGCs, SDF1 promotes regeneration from non-αRGCs and enables the latter cells to respond robustly to Pten deletion; however, SDF1 surprisingly diminishes the response of αRGCs to Pten deletion. When combined with inflammation and Pten deletion, SDF1 enables many RGCs to regenerate axons the entire length of the optic nerve. Thus, SDF1 complements the effects of Ocm in mediating inflammation-induced regeneration and enables different RGC subtypes to respond to Pten deletion.

Intracellular Zn2+ promotes extracellular matrix remodeling in dexamethasone-treated trabecular meshwork.

Given the widespread application of glucocorticoids in ophthalmology, the associated elevation of intraocular pressure (IOP) has long been a vexing concern for clinicians, yet the underlying mechanisms remain inconclusive. Much of the discussion focuses on the extracellular matrix (ECM) of trabecular meshwork (TM). It is widely agreed that glucocorticoids impact the expression of matrix metalloproteinases (MMPs), leading to ECM deposition. Since Zn2+ is vital for MMPs, we explored its role in ECM alterations induced by dexamethasone (DEX). Our study revealed that in human TM cells treated with DEX, the level of intracellular Zn2+ significantly decreased, accompanied by impaired extracellular Zn2+ uptake. This correlated with changes in several Zrt-, Irt-related proteins (ZIPs) and metallothionein. ZIP8 knockdown impaired extracellular Zn2+ uptake, but Zn2+ chelation did not affect ZIP8 expression. Resembling DEX's effects, chelation of Zn2+ decreased MMP2 expression, increased the deposition of ECM proteins, and induced structural disarray of ECM. Conversely, supplementation of exogenous Zn2+ in DEX-treated cells ameliorated these outcomes. Notably, dietary zinc supplementation in mice significantly reduced DEX-induced IOP elevation and collagen content in TM, thereby rescuing the visual function of the mice. These findings underscore zinc's pivotal role in ECM regulation, providing a novel perspective on the pathogenesis of glaucoma.NEW & NOTEWORTHY Our study explores zinc's pivotal role in mitigating extracellular matrix dysregulation in the trabecular meshwork and glucocorticoid-induced ocular hypertension. We found that in human trabecular meshwork cells treated with dexamethasone, intracellular Zn2+ significantly decreased, accompanied by impaired extracellular Zn2+ uptake. Zinc supplementation rescues visual function by modulating extracellular matrix proteins and lowering intraocular pressure, offering a direction for further exploration in glaucoma management.

Cotton leaf curl Multan virus C4 protein suppresses autophagy to facilitate viral infection.

Autophagy plays an important role in plant antiviral defense. Several plant viruses are reported to encode viral suppressor of autophagy (VSA) to prevent autophagy for effective virus infection. However, whether and how other viruses, in particular DNA viruses, also encode VSAs to affect viral infection in plants is unknown. Here, we report that the C4 protein encoded by Cotton leaf curl Multan geminivirus (CLCuMuV) inhibits autophagy by binding to the autophagy negative regulator eukaryotic translation initiation factor 4A (eIF4A) to enhance the eIF4A-Autophagy-related protein 5 (ATG5) interaction. By contrast, the R54A or R54K mutation in C4 abolishes its capacity to interact with eIF4A, and neither C4R54A nor C4R54K can suppress autophagy. However, the R54 residue is not essential for C4 to interfere with transcriptional gene silencing or post-transcriptional gene silencing. Moreover, plants infected with mutated CLCuMuV-C4R54K develop less severe symptoms with decreased levels of viral DNA. These findings reveal a molecular mechanism underlying how the DNA virus CLCuMuV deploys a VSA to subdue host cellular antiviral autophagy defense and uphold viral infection in plants.

Global miRNA profiling reveals key molecules that contribute to different chronic lymphocytic leukemia incidences in Asian and Western populations.

It has been known for decades that the incidence of chronic lymphocytic leukemia (CLL) is significantly lower in Asia than in Western countries, but the reason responsible for this difference still remains a major knowledge gap. Using GeneChip® miRNA array to analyze the global microRNA expression in B lymphocytes from Asian and Western CLL patients and healthy individuals, we have identified microRNA with CLL-promoting or suppressive functions that are differentially expressed in Asian and Western individuals. In particular, miR-4485 is upregulated in CLL patients of both ethnic groups, and its expression is significantly lower in Asian healthy individuals. Genetic silencing of miR-4485 in CLL cells suppresses leukemia cell growth, whereas ectopic expression of miR-4485 promotes cell proliferation. Mechanistically, miR-4485 exerts its CLL-promoting activity by inhibiting the expression of TGR5 and activating the ERK1/2 pathway. In contrast, miR-138, miR-181a, miR- 181c, miR-181d, and miR-363 with tumor-suppressive function are highly expressed in Asian healthy individuals. Our study suggests that differential expression of several important microRNA with pro- or anti-CLL functions in Asian and Western B lymphocytes likely contributes to the difference in CLL incidence between the two ethnic groups, and that miR-4485 and its downstream molecule TGR5 could be potential therapeutic targets.

Acute caval thrombosis leading to obstructive shock in the early post insertion period of an inferior vena cava filter: a case report and literature review.

BACKGROUND: Obstructive shock is extremely rare in clinical practice and is caused by acute blood flow obstruction in the central vessels of either the systemic or pulmonary circulation. Utilizing inferior vena cava filters (IVCFs) to prevent pulmonary embolism (PE) is associated with some potential complications, such as inferior vena cava thrombosis (IVCT). Shock as a direct result of IVCT is rare. We present a case of obstructive shock secondary to extensive IVCT caused by inadequate anticoagulant therapy after the placement of an IVCF. CASE PRESENTATION: A 63-year-old male patient with a traffic accident injury presented orthopaedic trauma and lower limb deep vein thrombosis (DVT). He experienced sudden and severe abdominal pain with hypotension, tachycardia, tachypnea, oliguria and peripheral oedema 5 days after IVCF placement and 3 days after cessation of anticoagulant therapy. Considering that empirical anti-shock treatment lasted for a while and the curative effect was poor, we finally recognized the affected vessels and focused on the reason for obstructive shock through imaging findings-inferior vena cava thrombosis and occlusion. The shock state immediately resolved after thrombus aspiration. The same type of shock occurred again 6 days later during transfer from the ICU to general wards and the same treatment was administered. The patient recovered smoothly in the later stage, and the postoperative follow-up at 1, 3, and 12 months showed good results. CONCLUSION: This case alerts clinicians that it is crucial to ensure adequate anticoagulation therapy after IVCF placement, and when a patient presents with symptoms such as hypotension, tachycardia, and lower limb and scrotal oedema postoperatively, immediate consideration should be given to the possibility of obstructive shock, and prompt intervention should be based on the underlying cause.

Description and genomic characterization of Cohnella caldifontis sp. nov., isolated from hot springs in Yunnan province, south-west China.

A bacterial strain, Gram staining positive, strictly aerobic, rod-shaped, motile bacterium with flagellum and endospore-forming, designated strain YIM B05605T, was isolated from soil sampled in Hamazui hot springs, Tengchong City, Yunnan province, China. Optimum growth for the strain occurred at pH 7.0 and 45 °C. MK-7 was the main menaquinone in the strain YIM B05605T. The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. Diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidylmonomethylethanolamine (PME), unidentified glycolipid (GL), three unknown aminophospholipids (APLs) and unidentified polarlipid (PL) were part of the polar lipid profile. The major fatty acids were anteiso-C15:0 and iso-C16:0. The DNA G + C content of the type strain was 58.76%. Genome-based phylogenetic analysis confirmed that strain YIM B05605T formed a distinct phylogenetic cluster within the genus Cohnella. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values of strain YIM B05605T with the most related species C. fontinalis YT-1101T were 73.42% and 15.7%. Functional analysis by NR, Swiss-prot, Pfam, eggNOG, GO, KEGG databases revealed that strain YIM B05605T has 13 genes related to the sulfur cycle, 2 genes related to the nitrogen cycle. Based on phylogenomic and phylogenetic analyses coupled with phenotypic and chemotaxonomic characterizations, strain YIM B05605T could be classified as a novel species of the genus Cohnella, for which the name Cohnella caldifontis sp. nov., is proposed. The type strain is YIM B05605T (= CGMCC 1.60052T = KCTC 43462T = NBRC 115921T).

Association of vision and hearing impairment and dietary diversity among the oldest old in China: findings from the Chinese longitudinal healthy longevity survey.

BACKGROUND: The presence of sensory impairment among older age cohorts exerts a significant impact on both individuals and society generally. Although the impact of dietary patterns on health is vital across all stages of life, there still a paucity of comprehensive research on the association between dietary variety and sensory impairments. OBJECTIVE: To investigate the potential relationship between dietary diversity and the prevalence of visual and hearing impairment or dual sensory impairments (visual and hearing impairment) among the oldest old population. METHODS: This is a cross-sectional study relied on data obtained from the 2018 survey conducted by the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Subjects aged 80 and older with complete vision and hearing data were included in the study. Multivariate logistic regression models were developed to examine the association between dietary components and visual and hearing impairment while controlling for age, gender, socioeconomic demographic factors, living habits, other food habits, and general health status. RESULTS: The study included 10,093 participants, with an average age of 92.29 ± 7.75 years. Vision and hearing function were assessed based on the ability to distinguish the direction of the break in the circle and the requirement for hearing aids, respectively. Upon controlling for confounding variables, individuals with a greater Dietary Diversity Score (DDS, the number of food groups, range: 1-11) had a reduced likelihood of experiencing visual impairment (odds ratio [OR] = 0.944, 95% confidence interval [CI], 0.915-0.974) and dual sensory impairment (OR = 0.930, 95% CI, 0.905-0.955). In comparison to the low dietary variety group (insufficient dietary diversity, DDS < 4), the high dietary diversity group (sufficient dietary diversity, DDS ≥ 4) exhibited a decreased risk of visual impairment (OR = 0.820, 95% CI, 0.713-0.944) and dual sensory impairment (OR = 0.751, 95% CI, 0.667-0.846). However, no statistically significant correlation was observed between dietary diversity and the presence of only hearing impairment (OR = 0.924, 95% CI, 0.815-1.047) (P < 0.05). CONCLUSIONS AND IMPLICATIONS: The synthesis of research findings suggests that following diverse dietary patterns and healthy nutritional practices may be an effective and affordable way to prevent age-related decline in visual impairment and dual sensory impairment.

Predictive factors for iliac vein compression syndrome in patients with varicose veins.

OBJECTIVE: This study aimed to identify predictors of iliac vein compression syndrome (IVCS) in patients with varicose veins and to evaluate the necessity of routine lower extremity venography for preoperative assessment of these patients. METHODS: A retrospective analysis was conducted on data from 1165 patients with lower-limb varicose veins who underwent preoperative venography at Wuhan Union Hospital, Tongji Medical College, China, between January 2019 and September 2023. Logistic regression analyses identified factors associated with concurrent IVCS, and a nomogram was constructed based on these findings. RESULTS: Out of 1165 patients, 75 (6.4%) had IVCS according to venography and 769 had iliac vein ultrasound and found 2 (0.17%) positives. Multivariate analysis revealed the independent predictive value of left-sided involvement (odds ratio (OR) = 3.22, 95% confidence interval (CI): 1.24-8.33, p = 0.016), history of deep vein thrombosis (DVT) in the affected limb (OR = 3.11, 95% CI: 1.21-8.00, p = 0.018), pain (OR = 2.24, 95% CI: 1.17-4.26, p = 0.014), and positive results on iliac vein ultrasound (OR = 25.56, 95% CI: 2.10-311.26, p = 0.011) for the presence of IVCS in patients with lower-limb varicose veins. A nomogram incorporating these predictors demonstrated moderate predictive ability (AUV = 0.689, 95% CI: 0.607-0.771), with good calibration upon validation. CONCLUSIONS: Patients with left lower extremity varicose veins, pain symptoms, history of DVT in the affected limb, and positive iliac vein ultrasound findings are at a higher risk of concurrent IVCS. Patients with varicose veins who have the aforementioned risk factors may need to undergo preoperative angiography.

Eyesi direct ophthalmoscope simulator: an effective training tool for medical undergraduates.

INTRODUCTION: Non-ophthalmologists often lack sufficient operational training to use a direct ophthalmoscope proficiently, resulting in a global deficit of basic ophthalmological skills among general practitioners. This deficiency hampers the timely diagnosis, referral, and intervention of patients. Consequently, the optimization of teaching tools and methods to enhance teaching efficiency is imperative. This study explores the effectiveness of the Eyesi Direct Ophthalmoscope Simulator (Eyesi) as an innovative tool for fundus examination training. METHODS: Medical undergraduates were randomly assigned to Group A or B (n = 168). All participants completed a pre-training questionnaire. Group A received Eyesi training, while Group B underwent traditional direct ophthalmoscope (TDO) training. Subsequently, participants answered questionnaires relevant to their respective training methods. Both groups exchanged training tools and completed a summary questionnaire. RESULTS: After training, 54.17% of participants believed that images presented by the Eyesi were consistent with the real fundus. Group A scored significantly higher than Group B in fundus structure recognition and self-confidence in examination. The degree of mastery over fundus theory score increased from 6.10 ± 0.13 to 7.74 ± 0.16 (P < 0.001) in Group A, but Group B did not demonstrate a significant difference. We also compared undergraduates' tendencies for different learning purposes, 75.59% of participants preferred the Eyesi to TDO as a training tool, and 88.41% of participants were receptive to introducing the Eyesi in training. CONCLUSION: According to subjective participant feedback, Eyesi outperformed TDO in fundus observation, operational practice, and theoretical learning. It effectively equips undergraduates with fundus examination skills, potentially promoting the use of direct ophthalmoscopes in primary medical institutions.