Lactate administration improves laboratory parameters in murine models of iron overload

ABSTRACT

Current iron overload therapeutics have inherent drawbacks including perpetuated low hepcidin. Here, we unveiled that lactate, a potent hepcidin agonist, effectively reduced serum and hepatic iron levels in mouse models of iron overload with an improved erythropoiesis in β-thalassemic mice.

A detailed multi-omics analysis of GNB2 gene in human cancers

Abstract The Guanine-nucleotide binding protein 2 (GNB2) encodes for β2 subunit (Gβ2) of the G-protein complex. Keeping in view the increased demand of reliable biomarkers in cancer, the current study was planned to extensively explored GNB2 expression variation and its roles in different cancers using online available databases and diverse methodology. In view of our results, the GNB2 was notably up-regulated relative to corresponding controls in twenty three cancer types. As well, the elevated expression of GNB2 was found to be associated with the reduced overall survival (OS) of the Liver Hepatocellular Carcinoma (LIHC) and Rectum Adenocarcinoma (READ) only out of all analyzed cancer types. This implies GNB2 plays vital role in the tumorigenesis of LIHC and READ. Several additional analysis also explored six critical pathways and few important correlations related to GNB2 expression and different other parameters such as promoter methylation, tumor purity, CD8+ T immune cells infiltration, and genetic alteration, and chemotherapeutic drugs. In conclusion, GNB2 gene has been identified in this study as a shared potential biomarker (diagnostic and prognostic) of LIHC and READ.

Lactate modulates iron metabolism by binding soluble adenylyl cyclase

Overproduction of lactate (LA) can occur during exercise and in many diseases such as cancers. Individuals with hyperlactatemia often display anemia, decreased serum iron, and elevated hepcidin, a key regulator of iron metabolism. However, it is unknown whether and how LA regulates hepcidin expression. Here, we show LA binds to soluble adenylyl cyclase (sAC) in normal hepatocytes and affects systemic iron homeostasis in mice by increasing hepcidin expression. Comprehensive in vitro, in vivo, and in silico experiments show that the LA-sAC interaction raises cyclic adenosine monophosphate (cAMP) levels, which activates the PKA-Smad1/5/8 signaling pathway to increase hepcidin transcription. We verified this regulatory axis in wild-type mice and in mice with disordered iron homeostasis. LA also regulates hepcidin in humans at rest and subjected to extensive exercise that produce elevated LA. Our study links hyperlactatemia to iron deficiency, offering a mechanistic explanation for anemias seen in athletes and patients with lactic acidosis.

Clinical outcomes of intra-arterial chemotherapy combined with iodine-125 seed brachytherapy in the treatment of malignant superior vena cava syndrome caused by small cell lung cancer

PURPOSE

Currently there is a lack of effective treatment strategies for malignant superior vena cava syndrome (SVCS). We aim to investigate the therapeutic effect of intra-arterial chemotherapy (IAC) combined with the Single Needle Cone Puncture method for the ¹²⁵I brachytherapy (SNCP-¹²⁵I) in treating SVCS caused by stage III/IV Small Cell Lung Cancer (SCLC).

MATERIALS AND METHODS

Sixty-two patients with SCLC who developed SVCS from January 2014 to October 2020 were investigated in this study. Out of these 62 patients, 32 underwent IAC combined with SNCP-¹²⁵I (Group A) and 30 patients received IAC treatment only (Group B). Clinical symptom remission, response rate, disease control rate, and overall survival of these two groups of patients were analyzed and compared.

RESULTS

The remission rate of symptoms including dyspnea, edema, dysphagia, pectoralgia, and cough of malignant SVCS in Group A was significantly higher than that in Group B (70.5 and 50.53%, P=0.0004, respectively). The disease control rates (DCR, PR+CR+SD) of Group A and B were 87.5 and 66.7%, respectively (P=0.049). Response rates (RR, PR+CR) of Group A and Group B were 71.9 and 40% (P=0.011). The median overall survival (OS) of Group A was significantly longer than that in Group B which was 18 months compared to 11.75 months (P=0.0360).

CONCLUSIONS

IAC treatment effectively treated malignant SVCS in advanced SCLC patients. IAC combined with SNCP-¹²⁵I in the treatment of malignant SVCS caused by SCLC showed improved clinical outcomes including symptom remission and local tumor control rates than IAC treatment only in treating SCLC-induced malignant SVCS.

Clinical characteristics of central nervous system candidiasis due to Candida albicans in children: a single-center experience

BACKGROUND

Central nervous system candidiasis due to Candida albicans (CNSC) in children is easily misdiagnosed and is associated with poor outcomes and a high mortality rate. There is no big data research or systematic review of CNSC.

METHODS

Patients diagnosed as CNSC with positive culture results of Candida albicans in Beijing Children's Hospital affiliated to Capital Medical University from March 2010 to March 2019 were included. Patients receiving immunosuppressive therapy or transplantation, or with malignant tumours were excluded. We analysed the clinical characteristics, follow-up results, drug susceptibility tests and whole-exome sequencing (WES) results.

RESULTS

Thirty-three definitive patients were enrolled, including 22 males and 11 females. Twenty-five patients suffered from CNSC when they were less than 1 year old, and a total of 29 patients had high-risk factors. The main clinical manifestations were fever, convulsions, and positive neurological signs. Twenty-two patients had CNS infections alone, and 11 patients had CNS infections combined with invasive infections involving multiple sites. Twenty-seven cases had a positive CSF and/or blood culture at our hospital. All strains were susceptible to fluconazole, and 2 strains had intermediate susceptibility to voriconazole. As for amphotericin B, all the strains were wild type (WT). WES of 16 patients revealed 2 cases with CARD9 mutations, who suffered from recurrent onychomycosis or thrush before.

CONCLUSION

CNSC mostly existed in children younger than 1 year old, who all had underlying risk factors. CNSC patients with onset at an older age or with recurrent superficial fungal infections might have primary immunodeficiency.

New Deferric Amine Compounds Efficiently Chelate Excess Iron to Treat Iron Overload Disorders and to Prevent Ferroptosis

Excess iron accumulation occurs in organs of patients with certain genetic disorders or after repeated transfusions. No physiological mechanism is available to excrete excess iron and iron overload to promote lipid peroxidation to induce ferroptosis, thus iron chelation becomes critical for preventing ion toxicity in these patients. To date, several iron chelators have been approved for iron chelation therapy, such as deferiprone and deferoxamine, but the current iron chelators suffer from significant limitations. In this context, new agents are continuously sought. Here, a library of new deferric amine compounds (DFAs) with adjustable skeleton and flexibility is synthesized by adopting the beneficial properties of conventional chelators. After careful evaluations, compound DFA1 is found to have greater efficacy in binding iron through two molecular oxygens in the phenolic hydroxyl group and the nitrogen atom in the amine with a 2:1 stoichiometry. This compound remarkably ameliorates iron overload in diverse murine models through both oral and intravenous administration, including hemochromatosis, high iron diet-induced, and iron dextran-stimulated iron accumulation. Strikingly, this compound is found to suppress iron-induced ferroptosis by modulating the intracellular signaling that drives lipid peroxidation. This study opens a new approach for the development of iron chelators to treat iron overload.

High-throughput sequencing unravels the cell heterogeneity of cerebrospinal fluid in the bacterial meningitis of children

Bacterial meningitis (BM) is a common life-threatening infection in children that occurs in the central nervous system (CNS). The cytologic examination of cerebrospinal fluid (CSF) is a key parameter in the diagnosis of BM, but the heterogeneity of cells in the CSF has not been elucidated, which limits the current understanding of BM neuroinflammation. In this study, CSF samples were collected from a number of BM patients who were in different stages of disease progression. Single-cell RNA-sequencing (scRNA-seq), with additional bulk transcriptome sequencing, was conducted to decipher the characteristics of CSF cells in BM progression. A total of 18 immune cell clusters in CSF were identified, including two neutrophils, two monocytes, one macrophage, four myeloid dendritic cells, five T cells, one natural killer cell, one B cell, one plasmacytoid dendritic cell, and one plasma cell subtype. Their population profiles and dynamics in the initial onset, remission, and recovery stages during BM progression were also characterized, which showed decreased proportions of myeloid cells and increased proportions of lymphoid cells with disease progression. One novel neutrophil subtype, FFAR2+TNFAIP6+ neutrophils, and one novel monocyte subtype, THBS1+IL1B+ monocytes, were discovered, and their quantity changes positively correlated with the intensity of the inflammatory response in the CSF during BM. In addition, the CSF of BM patients with unsatisfactory therapeutic responses presented with different cell heterogeneity compared to the CSF of BM patients with satisfactory therapeutic responses, and their CSF featured altered intercellular communications and increased proportions of type II myeloid dendritic cells and plasmacytoid dendritic cells. Moreover, the bulk transcriptome profiles of autologous CSF cells and peripheral blood leukocytes of BM patients showed that the immune cells in these two physiological compartments exhibited distinct immune responses under different onset conditions. In particular, the CSF cells showed a high expression of macrophage characteristic genes and a low expression of platelet characteristic genes compared with peripheral blood leukocytes. Our study conducted an in-depth exploration of the characteristics of CSF cells in BM progression, which provided novel insights into immune cell engagement in acute CNS infection.

Microdermabrasion facilitates direct current stimulation by lowering skin resistance

Background

Transcranial direct current stimulation (tDCS) is reported to induce irritating skin sensations and occasional skin injuries, which limits the applied tDCS dose. Additionally, tDCS hardware safety profile prevents high current delivery when skin resistance is high.

Objective

To test if decreasing skin resistance can enable high-dose tDCS delivery without increasing tDCS-related skin sensations or device hardware limits.

Methods

We compared the effect of microdermabrasion and sonication on 2 mA direct current stimulation (DCS) through forearm skin for 2-3 min on 20 subjects. We also surveyed the subjects using a questionnaire throughout the procedure. We used a linear mixed-effects model for repeated-measures and multiple logistic regression, with adjustments for age, race, gender and visit.

Results

Microdermabrasion, with/out sonication, led to significant decrease in skin resistance (1.6 ± 0.1 kΩ or ∼32% decrease, p < 0.0001). The decrease with sonication alone (0.4 ± 0.1 kΩ or ∼7% decrease, p = 0.0016) was comparable to that of sham (0.3 ± 0.1 kΩ or ∼5% decrease, p = 0.0414). There was no increase in the skin-electrode interface temperature. The perceived DCS-related sensations did not differ across skin preparation procedures (p > 0.16), but microdermabrasion (when not combined with sonication) led to increased perceived sensation (p < 0.01).

Conclusions

Microdermabrasion (with/out sonication) resulted in reduced skin resistance without increase in perceived skin sensations with DCS. Higher current can be delivered with microdermabrasion-pre-treated skin without changing the device hardware while reducing, otherwise higher voltage required to deliver the same amount of current.

[Analysis of clinical features and poor prognostic factors of acute hematogenous osteomyelitis in children]

Objective: To analyze the clinical characteristics, pathogenic bacteria, complications and risk factors of prognosis of acute hematogenous osteomyelitis in children. Methods: The clinical manifestations, laboratorg tests, etiological charateristics and clinical data of 107 patients with acute hematogenous osteomyelitis admitted to Beijing Children's Hospital from January 2017 to December 2020 were retrospectively analyzed. According to the drug sensitivity results of Staphylococcus aureus, the group was divided into methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible Staphylococcus aureus (MSSA) group; according to the presence or absence of complications, the group was divided into the group with and without complications; according to the prognosis of the follow-up children, the group was divided into good prognosis and poor prognosis. The χ² test or Mann-Whitney U test used for comparison between groups, and Logistic regression was used to analyze the risk factors for complications and prognosis. Results: Of the 107 patients, 62 were males and 45 were females. The age of presentation was 5.6 (1.7, 10.0) years, including 5 patients (4.7%) age from >28 days to 3 months, 46 patients (43.0%) age from >3 months to 5 years, 43 patients (40.2%)>5-12 years of age, and 13 patients (12.1%)>12-18 years of age. The first symptoms were acute fever in 35 patients (32.7%), limb pain in 24 patients (22.4%), and fever with limb pain in 23 patients (21.5%). Pathogen culture was positive in 75 patients (70.1%), Streptococcus pyogenes, Salmonella enterica and Escherichia coli in 1 case (1.4%) each, and Staphylococcus aureus in 72 cases (96.0%), among them, 47 cases were MSSA, 22 cases were MRSA, and 3 cases had positive reports of Staphylococcus aureus from other hospitals without drug-sensitive tests. The proportion of infected children living in rural areas and receiving surgical treatment was higher in the MRSA group than in the MSSA group (14 cases (63.6%) vs. 18 cases (38.3%) and 21 cases (95.5%) vs. 33 cases (70.2%), χ²=3.87, 4.23, both P<0.05). Sixty-five children had no complications while 42 children (39.3%) suffered from complications. Common complications consisted of 19 cases (17.8%) of sepsis, 17 cases (15.9%) of septic arthritis, and 12 cases (11.2%) of venous thrombosis. The group with complications showed higher mental changes, decreased appetite and (or) weakness, positive pathogenic cultures, and time from admission to surgery than the group without complications (18 cases (42.9%) vs. 9 cases (13.8%), 20 cases (47.6%) vs. 12 cases (18.5%), 34 cases (81.0%) vs. 41 cases (63.1%), 3.5 (2.0, 6.0) vs. 2.0 (1.0, 4.0) d,χ²=11.38, 10.35, 3.89, Z=2.21, all P<0.05). The poor prognosis group had more comorbidities, combined local complications, and positive aureus than the good prognosis group (10/15 vs. 34.9% (30/86), 7/15 vs. 17.4% (15/86), 14/15 vs. 61.6% (53/86), χ²=5.39, 6.40, 4.42, all P<0.05). Multifactorial Logistic regression analysis showed that acute phase C-reactive protein (CRP) was both an independent risk factor for complications (OR=1.01, 95%CI 1.01-1.02) and an independent risk factor for poor prognosis (OR=1.01, 95%CI 1.00-1.02). Conclusions: The first symptoms of acute hematogenous osteomyelitis are acute fever, limb pain, and fever with limb pain are most common. Staphylococcus aureus is the most common pathogenic organism. Those with loss of appetite and (or) weakness, mental changes, positive pathogenic cultures, and longer time between admission and surgery are prone to complications. Those with complications, combined local complications, and positive for Staphylococcus aureus had a poor prognosis. Elevated CRP is an independent risk factor not only for complications but for poor prognosis as well.

Talaromynoids A-E: Five New Fusicoccane Diterpenoids from the Endophytic Fungus Talaromyces sp. DC-26

Talaromynoids A-E (1-5), five new fusicoccane diterpenoids, were obtained from the endophytic fungus Talaromyces sp. DC-26, which was isolated from a wild leech. Talaromynoid A (1) represents the first fusicoccane diterpenoid bearing an unexpected 5-7-5 tricyclic ring system, which is possibly derived from normal 5-8-5 ones by ring contraction. Talaromynoid E (5) is characterized by an unusual oxygen bridge between C-1 and C-8 that establishes the eight-membered ring B to be a 9-oxo-bicyclo[3.3.1]nonane. Structures of 1-5 with absolute configurations were determined by extensive NMR spectral analyses, electronic circular dichroism (ECD) calculations, X-ray diffraction analyses, and acid hydrolysis.

LncRNA MT1DP promotes cadmium-induced DNA replication stress by inhibiting chromatin recruitment of SMARCAL1

Cadmium (Cd) is a well-known carcinogenic metal and widespread environmental pollutant. The effect of Cd-induced carcinogenesis is partly due to accumulated DNA damage and chromosomal aberrations, but the exact mechanisms underlying the genotoxicity of Cd have not been clearly understood. Here, we found that one long non-coding RNA MT1DP is participated in Cd-induced DNA damage and replication stress. Through analyzing the residents from Cd-contaminated area in Southern China, we found that blood DNA repair genes are down-regulated in individuals with high urine Cd values compared to those with low urine Cd values, which contrast to the blood MT1DP levels. Through in vitro experiments, we found that MT1DP promotes Cd-induced DNA damage response, genome instability and replication fork stalling. Mechanically, upon Cd treatment, ATR is activated to enhance HIF-1α expression, which in turn promotes the transcription level of MT1DP. Subsequently MT1DP is recruited on the chromatin and binds to SMARCAL1 to competitive inhibit latter's interaction with RPA complexes, finally leading to increased replication stress and DNA damage. In summary, this study provides clear evidence for the role of epigenetic regulation on the genotoxic effect of Cd, and MT1DP-mediated replication stress may represent a novel mechanism for Cd-induced carcinogenesis.

Palladium Nanoplate-Based IL-6 Receptor Antagonists Ameliorate Cancer-Related Anemia and Simultaneously Inhibit Cancer Progression

In recent years, targeted therapies and immunotherapeutics, along with conventional chemo- and radiotherapy, have greatly improved cancer treatments. Unfortunately, in cancer patients, anemia, either as a complication of cancer progression or as the result of cancer treatment, undermines the expected therapeutic efficacy. Here, we developed a smart nanosystem based on the palladium nanoplates (PdPLs) to deliver tocilizumab (TCZ, a widely used IL-6R antibody) to the liver for specific blockade of IL-6/IL-6R signaling to correct anemia. With chemical modifications, this nanosystem delivered a large mass of TCZ and enhanced liver delivery, inducing a marked suppression of hepcidin expression as a result of diminished IL-6 signaling. Through this mechanism, significant suppression of tumor progression was realized (at least in part) because of the corrected anemia after treatment.

m6A demethylation of cytidine deaminase APOBEC3B mRNA orchestrates arsenic-induced mutagenesis

The cytidine deaminase APOBEC3B (A3B) is an endogenous inducer of somatic mutations and causes chromosomal instability by converting cytosine to uracil in single-stranded DNA. Therefore, identification of factors and mechanisms that mediate A3B expression will be helpful for developing therapeutic approaches to decrease DNA mutagenesis. Arsenic (As) is one well-known mutagen and carcinogen, but the mechanisms by which it induces mutations have not been fully elucidated. Herein, we show that A3B is upregulated and required for As-induced DNA damage and mutagenesis. We found that As treatment causes a decrease of N6-methyladenosine (m6A) modification near the stop codon of A3B, consequently increasing the stability of A3B mRNA. We further reveal that the demethylase FTO is responsible for As-reduced m6A modification of A3B, leading to increased A3B expression and DNA mutation rates in a manner dependent on the m6A reader YTHDF2. Our in vivo data also confirm that A3B is a downstream target of FTO in As-exposed lung tissues. In addition, FTO protein is highly expressed and positively correlates with the protein levels of A3B in tumor samples from human non-small cell lung cancer patients. These findings indicate a previously unrecognized role of A3B in As-triggered somatic mutation and might open new avenues to reduce DNA mutagenesis by targeting the FTO/m6A axis.

Exploring optimal heart team protocol to improve decision-making stability for complex coronary artery disease: a sequential explanatory mixed method study

Background

Although heart team was recommended by guideline for decision-making in patients with complex coronary artery disease (CAD), the decision-making stability was lack of evaluation and optimal protocol remained unknown.

Purpose

We aimed to assess inter-team agreement for revascularization decision-making and related influencing factors, so as to provide recommendations for optimal protocol.

Methods

A sequential, explanatory mixed method study was conducted, including (1) a cross-sectional study retrospectively enrolling patients with complex CAD and four heart teams to assess the inter-team decision-making agreement and (2) a qualitative study that semi-structurally interviewed all heart team members to analyze the potential factors associated with decision-making discrepancy. Primary outcome was kappa value of inter-team decision-making agreement. Inductive thematic analysis was used to generate themes and subthemes attributing to decision-making discrepancy. Integrating qualitative and quantitative data, we explained how each subtheme affected decision-making agreement and provided corresponding recommendations based on these explanations. Finally, we provided a detailed heart team protocol by integrating our recommendations, published experience and guideline. Patient sample size was precalculated and interviewee sample size was identified by theoretical saturation.

Results

A total of 101 patients with complex CAD were randomly enrolled from a consecutive angiography registry. Sixteen specialists were invited and randomly established four heart teams to make decisions for enrolled patients. Inter-team decision-making agreement was moderate (kappa 0.582) (Table 1). Decision-making may be influenced at three themes (specialist quality; team composition; meeting process) and ten subthemes (decision thought; understanding of disease and evidence; understanding of other discipline; personality; learning curve; personnel quality; number of team members; discipline selection; ratio of different disciplines and meeting form). Recommendations at five levels were provided, including (1) specialist selection, (2) specialist training, (3) team composition, (4) team training and (5) meeting process. A detailed implementation protocol to establish and deploy a qualified heart team was generated.

Conclusions

Agreement between heart teams for revascularization decision-making in patients with complex CAD was moderate. Five recommendations to improve heart team modality were provided based on factors associated with decision-making discrepancy. A detailed heart team implementation protocol came into being. Randomized controlled trial was warranted to further confirm the protocol.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): the national key research and development program;Beijing municipal commission of science and technology project Table 1. Inter-team agreement of decision making

Improved robot-assisted laparoscopic telesurgery: feasibility of network converged communication

The converged transmission-assisted network communication architecture used in this study could meet the requirements of telesurgery, and effectively guarantee the security and immediacy of communication. With the security, flexibility, and universality of the network converged transmission, the clinical practical application of telesurgery and telemedicine would step up to a higher level.