Prognostic value of the systemic immune-inflammation index in critically ill elderly patients with hip fracture: evidence from MIMIC (2008-2019).

Background: The systemic immune-inflammation index (SII) showed an extensive link between immunological dysfunction and the activation of systemic inflammation. Several studies have confirmed the application of SII to orthopedic diseases. However, the significance of SII in critically ill elderly individuals with hip fracture who require intensive care unit (ICU) admission is not yet known. This study centered on exploring the relationship between SII and clinical outcomes among critically ill elderly hip fracture individuals. Methods: The study centered around elderly patients experiencing severe illness following hip fractures and requiring admission to the ICU. These patients from the MIMIC-IV database formed the basis of this study's cohort. We stratified them into quartiles according to their SII levels. The results involved the mortality at 30 days and 1 year post-admission. Then we employ Cox proportional hazards regression analysis as well as restricted cubic splines to explore the association between the SII and clinical results in critically ill elderly patients with hip fracture. Results: The study encompassed 991 participants, among whom 63.98% identified as females. Notably, the mortality rates attributed to any cause within 30 days and 1 year after hospitalization stood at 19.68 and 33.40%, respectively. The multivariate Cox proportional hazards model disclosed a significant correlation between an elevated SII and all-cause mortality. Following adjustments for confounding variables, individuals with a high SII showed a notable correlation with 30-day mortality [adjusted hazard ratio (HR), 1.065; 95% confidence interval (CI), 1.044-1.087; p < 0.001] and 1-year mortality (adjusted HR, 1.051; 95% CI, 1.029-1.074; p < 0.001). Furthermore, the analysis of restricted cubic splines demonstrated a progressive increase in the risk of all-cause death as the SII value rose. Conclusion: Among critically ill elderly patients with hip fracture, the SII exhibits a non-linear association that positively correlates with both 30-day and 1-year all-cause mortality rates. The revelation indicates that the SII may play a vital role in identifying patients with hip fractures who face an escalated risk of mortality due to any cause.

Three new endophytic Apiospora species (Apiosporaceae, Amphisphaeriales) from China.

Apiospora species are widely distributed fungi with diverse lifestyles, primarily functioning as plant pathogens, as well as exhibiting saprophytic and endophytic behaviors. This study reports the discovery of three new species of Apiospora, namely A.gongcheniae, A.paragongcheniae, and A.neogongcheniae, isolated from healthy Poaceae plants in China. These novel species were identified through a multi-gene phylogenetic analysis. The phylogenetic analysis of the combined ITS, LSU, tef1, and tub2 sequence data revealed that the three new species formed a robustly supported clade with A.garethjonesii, A.neogarethjonesii, A.setostroma, A.subrosea, A.mytilomorpha, and A.neobambusae. Detailed descriptions of the newly discovered species are provided and compared with closely related species to enhance our understanding of the genus Apiospora.

Targeting pyruvate dehydrogenase kinase 1 overcomes EGFR C797S mutation-driven osimertinib resistance in non-small cell lung cancer.

Osimertinib, a selective third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), effectively targets the EGFR T790M mutant in non-small cell lung cancer (NSCLC). However, the newly identified EGFR C797S mutation confers resistance to osimertinib. In this study, we explored the role of pyruvate dehydrogenase kinase 1 (PDK1) in osimertinib resistance. Patients exhibiting osimertinib resistance initially displayed elevated PDK1 expression. Osimertinib-resistant cell lines with the EGFR C797S mutation were established using A549, NCI-H292, PC-9, and NCI-H1975 NSCLC cells for both in vitro and in vivo investigations. These EGFR C797S mutant cells exhibited heightened phosphorylation of EGFR, leading to the activation of downstream oncogenic pathways. The EGFR C797S mutation appeared to increase PDK1-driven glycolysis through the EGFR/AKT/HIF-1α axis. Combining osimertinib with the PDK1 inhibitor leelamine helped successfully overcome osimertinib resistance in allograft models. CRISPR-mediated PDK1 knockout effectively inhibited tumor formation in xenograft models. Our study established a clear link between the EGFR C797S mutation and elevated PDK1 expression, opening new avenues for the discovery of targeted therapies and improving our understanding of the roles of EGFR mutations in cancer progression.

Robotic portal resection for mediastinal tumours: a prospective observational study.

BACKGROUND: To demonstrate the effectiveness and feasibility of robotic portal resection (RPR) for mediastinal tumour using a prospectively collected database. METHODS: Data from 73 consecutive patients with mediastinal tumours who underwent RPRs were prospectively collected from August 2018 to April 2023. All patients underwent chest and abdominal enhanced computed tomography (CT) and preoperative multidisciplinary team (MDT) discussion. The patients were stratified into two groups based on tumour size: Group A (tumour size < 4 cm) and Group B (tumour size ≥ 4 cm). General clinical characteristics, surgical procedures, and short outcomes were promptly recorded. RESULTS: All of the cases were scheduled for RPRs. One patient (1/73, 1.4%) was switched to a small utility incision approach because of extensive pleural adhesion. Two patients (2.8%) converted to sternotomy, however, no perioperative deaths occurred. Most of the tumours were located in the anterior mediastinum (51/73, 69.9%). Thymoma (27/73, 37.0%) and thymic cyst (16/73, 21.9%) were the most common diagnoses. The median diameter of tumours was 3.2 cm (IQR, 2.4-4.5 cm). The median total operative time was 61.0 min (IQR, 50.0-90.0 min). The median intraoperative blood loss was 20 mL (IQR, 5.0-30.0 ml), and only one patient (1.4%) experienced an intraoperative complication. The median length of hospital stay was 3 days (IQR, 2-4 days). Compared with Group A, the median total operative time and console time of Group B were significantly longer (P = 0.006 and P = 0.003, respectively). The volume of drainage on the first postoperative day was greater in group B than in group A (P = 0.013). CONCLUSION: RPR is a safe and effective technique for mediastinal tumour treatment, which can expand the application of minimally invasive surgery for the removal of complicated mediastinal tumours.

Optimal allocation of resources among general and species-specific tools for plant pest biosecurity surveillance.

This paper proposes a surveillance model for plant pests that can optimally allocate resources among survey tools with varying properties. While some survey tools are highly specific for the detection of a single pest species, others are more generalized. There is considerable variation in the cost and sensitivity of these tools, but there are no guidelines or frameworks for identifying which tools are most cost-effective when used in surveillance programs that target the detection of newly invaded populations. To address this gap, we applied our model to design a trapping surveillance program in New Zealand for bark- and wood-boring insects, some of the most serious forest pests worldwide. Our findings show that exclusively utilizing generalized traps (GTs) proves to be highly cost-effective across a wide range of scenarios, particularly when they are capable of capturing all pest species. Implementing surveillance programs that only employ specialized traps (ST) is cost-effective only when these traps can detect highly damaging pests. However, even in such cases, they significantly lag in cost-effectiveness compared to GT-only programs due to their restricted coverage. When both GTs and STs are used in an integrated surveillance program, the total expected cost (TEC) generally diminishes when compared to programs relying on a single type of trap. However, this relative reduction in TEC is only marginally larger than that achieved with GT-only programs, as long as highly damaging species can be detected by GTs. The proportion of STs among the optimal required traps fluctuates based on several factors, including the relative pricing of GTs and STs, pest arrival rates, potential damage, and, more prominently, the coverage capacity of GTs. Our analysis suggests that deploying GTs extensively across landscapes appears to be more cost-effective in areas with either very high or very low levels of relative risk density, potential damage, and arrival rate. Finally, STs are less likely to be required when the pests that are detected by those tools have a higher likelihood of successful eradication because delaying detection becomes less costly for these species.

[Effects of Microplastics on the Leaching of Nutrients and Cadmium from Soil].

The environmental effects of microplastics, which are considered a type of emerging contaminants, have attracted increasing concern due to their small size, large specific surface area, strong adsorption capacity, and low degradability. Microplastics can change soil properties and affect the migration ability of nutrients and pollutants in soil, but their effects on the leaching of soil nutrients and heavy metals have not been sufficiently studied. A soil column leaching experiment was conducted to explore the effects of polystyrene (PS) and polylactic acid (PLA) microplastics at different mass fractions (0%, 0.2%, and 2%) on the leaching of nutrients and cadmium under simulated rainfall scenarios. The results showed that increasing rainfall intensity enhanced the leaching of nutrients and cadmium from soil. During downpour conditions, 2% PS significantly increased the leaching of total nitrogen and the content of available phosphorus in soil and reduced the leaching of inorganic phosphorus and the content of ammonium nitrogen in the soil, whereas it increased the content of available potassium during heavy rain. By comparison, 2% PLA reduced the leaching of nitrate nitrogen during heavy rain and intense rainfall and decreased the content of ammonium nitrogen in soil during intense rainfall and downpour conditions and the content of total nitrogen in soil during downpours. In addition, 0.2% PLA significantly increased cadmium leaching during downpours. To conclude, the effects of microplastics on the leaching of nutrients and cadmium were dependent on the type and concentration of microplastics, as well as the rainfall level. Our findings showed that the microplastics derived from both nondegradable PS and biodegradable PLA could affect the leaching of nutrients and heavy metals from soil.

Enhanced reduction of nitrate by TDER packed with surface-modified plastic particles electrodes.

Based on Iron cathodes, nitrate could be selectively decomposed into other lower-valence nitrogen compounds, including ammonia, nitrogen gas, nitrite and nitric oxide, but the removal efficiencies of nitrate and total nitrogen (TN), are affected significantly by the synergistic effects of anodes, chloride electrolyte and conductive plastic particles electrodes. In this work, the base material Titanium (Ti) metal plates and plastic particles which surfaces were mainly coated with Ru-Sn oxidizing compounds, were applied as plates anodes and conductive particles electrodes in Three Dimensional Electrode Reactors (TDER). The Ti/RuSn plate anodes showed excellent performance on degrading nitrate, more nitrogen gas (83.84%) and less ammonia (15.51%) was produced, less TN and Iron ion (0.02 mg/L) was left in the wastewater, and less amount of chemical sludge (0.20 g/L) was produced. Furthermore, the removal efficiencies of nitrate and TN were further increased by the surface-modified plastic particles, which were cheap, reusable, corrosion-resistance, easy to obtain as manufactured materials and light to be suspended in waters. The degradation of nitrate and its intermediates was enhanced possibly by the continuous synergistic reactions initiated by hydrogen radicals, which was generated on the countless surficial active Ru-Sn sites of Ti/RuSn metal plate anodes and plastic particles electrodes, among residual nitrogen intermediates, most of ammonia was selectively converted to gaseous nitrogen by hypochlorite from chloride ion reaction.

Inhibition of protein arginine deiminase 4 prevents inflammation-mediated heart failure in arthritis.

Rheumatoid arthritis is a prototypic inflammatory condition with affected patients being at greater risk of incident heart failure (HF). Targeting innate immune cell function in the pathogenesis of HF bears the potential to guide the development of future therapies. A collagen-induced arthritis (CIA) model in DBA/1 J mice was used to generate arthritis. Mice with CIA developed concentric hypertrophic myocardial remodeling, left ventricular (LV) diastolic dysfunction, and HF with elevated plasma B-type natriuretic peptide levels but preserved LV ejection fraction. Key features of HF in CIA were increased infiltration of activated neutrophils, deposition of neutrophil extracellular traps in the myocardium, and increased tissue levels of the proinflammatory cytokine IL-1ß. Specific inhibition of protein arginine deiminase 4 (PAD4) by an orally available inhibitor (JBI-589), administered after the onset of clinical arthritis, prevented HF with reduced neutrophil infiltration. We identify PAD4-mediated neutrophil activation and recruitment as the key thromboinflammatory pathway driving HF development in arthritis. Targeting PAD4 may be a viable therapeutic approach for the prevention of HF secondary to chronic inflammation.

Short-term outcomes of robotic lobectomy versus video-assisted lobectomy in patients with pulmonary neoplasms.

BACKGROUND: To explore whether robotic lobectomy (RL) is superior to video-assisted lobectomy (VAL) in terms of short-term outcomes in patients with pulmonary neoplasms. METHODS: From January 30, 2019 to February 28, 2022, a series of consecutive minimally invasive lobectomies were performed for patients with pulmonary neoplasms. Perioperative outcomes such as operation time, blood loss, dissected lymph nodes (LNs), surgical complications, postoperative pain control, length of postoperative stay in hospital, and total cost of hospitalization were compared. RESULTS: A total of 336 cases including 173 RLs and 163 VALs were enrolled. Baseline characteristics were comparable between groups. RLs were associated with shorter operation time (median [interquadrant range, IQR], 107 min [90-130] vs. 120 min [100-149], p < 0.001), less blood loss (median [IQR], 50 mL [30-60] vs. 50 mL [50-80], p = 0.02), and lower blood transfusion rate (3.5% vs. 9.8%, p = 0.02) compared with VALs. More LNs were harvested by the robotic approach (median [IQR], 29 [20-41] vs. 22 [15-45], p = 0.04). The incidences of conversion, major postoperative complications, extra analgesic usage, and postoperative length of stay were all comparable between the RL and VAL groups. As predicted, the total cost of hospitalization was greater in the RL group (median [IQR], $16728.35 [15682.16-17872.15] vs. $10713.47 [9662.13-11742.15], p < 0.001). CONCLUSION: RL improved surgical efficacy with shortened operative time, less blood loss, and more thorough LN dissection compared with VAL, compromised by higher cost.

Three new species of Trichoderma (Hypocreales, Hypocreaceae) from soils in China.

Trichoderma spp. are diverse fungi with wide distribution. In this study, we report on three new species of Trichoderma, namely T.nigricans, T.densissimum and T.paradensissimum, collected from soils in China. Their phylogenetic position of these novel species was determined by analyzing the concatenated sequences of the second largest nuclear RNA polymerase subunit encoding gene (rpb2) and the translation elongation factor 1- alpha encoding gene (tef1). The results of the phylogenetic analysis showed that each new species formed a distinct clade: T.nigricans is a new member of the Atroviride Clade, and T.densissimum and T.paradensissimum belong to the Harzianum Clade. A detailed description of the morphology and cultural characteristics of the newly discovered Trichoderma species is provided, and these characteristics were compared with those of closely related species to better understand the taxonomic relationships within the Trichoderma.

Comparison of Short-Term Outcomes Between Robot-Assisted and Video-Assisted Segmentectomy for Small Pulmonary Nodules: A Propensity Score-Matching Study.

BACKGROUND: Our study aimed to compare the short-term outcomes between robot-assisted segmentectomy (RAS) and video-assisted segmentectomy (VAS) for small pulmonary nodules. METHODS: The study included of 299 segmentectomies (132 RAS and 167 VAS procedures) for small pulmonary nodules between June 2018 and November 2021. The patients were divided into two groups: the RAS group and the VAS group. Propensity score-matching (PSM) analysis was performed to minimize bias. A logistic regression model was performed to identify the independent risk factors associated with complications. RESULTS: Before PSM, the following clinical variables were not balanced: age (P = 0.004), tumor size (P < 0.001), forced expiratory volume for 1 s (FEV1), and FEV1 percentage (P < 0.001). The patients with RAS had a shorter operative time (P = 0.014), less blood loss, a shorter postoperative hospital stay, less use of strong opioids, less drainage on postoperative day 1, and less postoperative total drainage, but more cost (all P < 0.001). Conversion to open surgery was performed for two patients in the VAS group but none in the RAS group. After PSM, 53 pairs were successfully matched. The data again suggested that the patients with RAS had less blood loss, a shorter postoperative hospital stay, and less use of strong opioids, but more cost (all P < 0.001). The operation time also was shorter in the RAS group, with a borderline statistically significant P value (0.053). CONCLUSIONS: In our study, RAS had better short-term outcomes than VAS, indicating a safer and more efficient technique than VAS.

Alleviation of arthritis through prevention of neutrophil extracellular traps by an orally available inhibitor of protein arginine deiminase 4.

Protein arginine deiminases (PAD) 4 is an enzyme that catalyzes citrullination of protein and its role in autoimmune diseases has been established through clinical genetics and gene knock out studies in mice. Further, studies with PAD4 - deficient mice have shown that PAD4 deficiency does not lead to increased infection or immune suppression, which makes PAD4 an attractive therapeutic target for auto-immune and inflammatory diseases. PAD4 has critical enzymatic role of promoting chromatin decondensation and neutrophil extracellular traps (NETs) formation that is associated with a number of immune-mediated pathological conditions. Here, we present a non-covalent PAD4 inhibitor JBI-589 with high PAD4 isoform selectivity and delineated its binding mode at 2.88 Å resolution by X-ray crystallography. We confirmed its effectiveness in inhibiting NET formation in vitro. Additionally, by using two mouse arthritis models for human rheumatoid arthritis (RA), the well-known disease associated with PAD4 clinically, we established its efficacy in vivo. These results suggest that JBI-589 would be beneficial for both PAD4 and NET-associated pathological conditions.

Defining the learning curve of robotic portal segmentectomy in small pulmonary lesions: a prospective observational study.

Although robotic segmentectomy has been applied for the treatment of small pulmonary lesions for many years, studies on the learning curve of robotic segmentectomy are quite limited. Thus, we aim to investigate the learning curve of robotic portal segmentectomy with 4 arms (RPS-4) using prospectively collected data in patients with small pulmonary lesions. One hundred consecutive patients with small pulmonary lesions who underwent RPS-4 between June 2018 and April 2021 were included in the study. Da Vinci Si/Xi systems were used to perform RPS-4. The mean operative time, console time, and docking time for the entire cohort were 119.2 ± 41.6, 85.0 ± 39.6, and 6.6 ± 2.8 min, respectively. The learning curve of RPS-4 can be divided into three different phases: 1-37 cases (learning phase), 38-78 cases (plateau phase), and > 78 cases (mastery phase). Moreover, 64 cases were required to ensure acceptable surgical outcomes. The total operative time (P < 0.001), console time (P < 0.001), blood loss (P < 0.001), and chest tube duration (P = 0.014) were reduced as experience increased. In conclusion, the learning curve of RPS-4 could be divided into three phases. 37 cases were required to pass the learning phase, and 78 cases were needed to truly master this technique.

Optical properties of sedimentary dissolved organic matter in intertidal zones along the coast of China: Influence of anthropogenic activities.

The intertidal zone, due to its location in the transition zone of terrestrial and marine ecosystems, is seriously disturbed by anthropogenic activities such as fuel combustion and industrial production, causing significant increase in dissolved organic matter (DOM). However, the distribution and properties of DOM in intertidal sediments at the large scale and their correlations with local socio-economic indicators remain unclear. In this study, we collected sediment samples from 13 intertidal zones across 11 coastal provinces in China and analyzed optical properties and compositions of sedimentary DOM. The results showed that the physico-chemical properties of sediment, such as pH and texture, affected the content of organic matter, thereby influencing the concentration of sedimentary DOM indirectly. The contents of fulvic acid- and protein-like components were relatively higher than humic acid-like component at all sampling sites. Moreover, urbanization could lead to the release of aromatic and humified organic matters into intertidal zones. Unlike coal, oil consumption exhibited positive correlation with SUVA254, indicating that the combustion of oil released more aromatic compounds. These findings revealed the impact of anthropogenic activities on sedimentary DOM and provided theoretical basis for predicting and regulating intertidal carbon sink.

NLRP3 inflammasome activation in neutrophils directs early inflammatory response in murine peritonitis.

NLR family pyrin domain containing 3 (NLRP3) inflammasome mediates caspase-1-dependent processing of inflammatory cytokines such as IL-1ß, an essential endothelial activator, and contributes to the pathology of inflammatory diseases. To evaluate the role of NLRP3 in neutrophils in endothelial activation, which is still elusive, we used the thioglycollate-induced peritonitis model characterized by an early neutrophil influx, on Nlrp3-/- and Nlrp3+/+ mice. Nlrp3-/- mice recruited fewer neutrophils than Nlrp3+/+ into the peritoneum and showed lower IL-1ß in peritoneal lavage fluid. The higher production of IL-1ß in Nlrp3+/+ was neutrophil-dependent as neutrophil depletion prevented the IL-1ß production. The Nlrp3+/+ neutrophils collected from the peritoneal fluid formed significantly more filaments (specks) than Nlrp3-/- neutrophils of ASC (apoptosis-associated speck-like protein containing a caspase activating and recruitment domain), a readout for inflammasome activation. Intravital microscopy revealed that leukocytes rolled significantly slower in Nlrp3+/+ venules than in Nlrp3-/-. Nlrp3-/- endothelial cells isolated from mesenteric vessels demonstrated a lower percentage of P-selectin-positive cells with lower intensity of surface P-selectin expression than the Nlrp3+/+ endothelial cells evaluated by flow cytometry. We conclude that neutrophils orchestrate acute thioglycollate-induced peritonitis by producing IL-1ß in an NLRP3-dependent manner. This increases endothelial P-selectin expression and leukocyte transmigration.

Estimating the transmission parameters of foot-and-mouth disease in Vietnam: A spatial-dynamic kernel-based model with outbreak and host data.

Foot-and-mouth disease (FMD) affects cloven-hoofed livestock and causes devastating damages to the world's economies. Being endemic in developing countries, FMD has imposed a significant threat to the FMD-freedom status in developed countries. The globally-concerted effort to eradicate FMD at its source has faced a substantial challenge of having little knowledge about how FMD spreads in developing countries. So far, FMD virus transmission parameters have been estimated based on only a dozen actual outbreak data, mostly in Europe. Meanwhile, the fundamental north-south differences in livestock production, trading, and quarantine systems have questioned the applicability of these estimates to developing countries. In this light, we aim to narrow the knowledge gap by estimating the FMD virus transmission parameters in an endemic country, Vietnam, the world's fifth- largest pork producer. We use the spatial-dynamic kernel-based approach combined with daily FMD incursion data and FMD-host census data. The estimation also considers livestock composition and livestock quantity by species, which can influence FMD transmission. In line with existing literature, we find that cattle and buffaloes have a larger influence on disease spread than pigs, and FMD transmission depends on the herd size and the distance between susceptible and infected premises. However, our findings show FMD virus can spread over a much more ample space in our case compared with those in existing literature (25 km and 50 km versus 10 km), and the kernels have much fatter tails. This difference is likely due to the weakness in biosecurity systems, poor implementation of surveillance and quarantine measures, and bad husbandry practices such as swill feeding, which are prevalent in developing countries. Thus, our estimated kernels will be helpful for Vietnam in developing suitable biosecurity measures to contain and eradicate the FMD virus. They are also highly relevant for other countries with livestock farming practices and climate conditions similar to those in Vietnam.

Anti-inflammatory protective effect of ADAMTS-13 in murine arthritis models.

BACKGROUND: Patients with rheumatoid arthritis (RA) have frequent thrombotic events with endothelial dysfunction. Von Willebrand factor (VWF) has been shown to bind neutrophil extracellular traps (NETs) and NETs are part of RA etiology. OBJECTIVES: This study aims to elucidate whether this prothrombotic status exacerbates inflammation in arthritis. Here we focus on the involvement of A Disintegrin And Metalloprotease with ThromboSpondin type 1 motif, member 13 (ADAMTS-13), an enzyme cleaving VWF and its effect on NET deposition and RA development. METHODS: We evaluated the influence of the Adamts13 gene and recombinant human ADAMTS-13 (rhADAMTS-13) on arthritis in the mouse models of collagen-induced arthritis (CIA). We also assessed VWF and NETs in synovial tissue. RESULTS: Several Adamts13-/- mice developed arthritis, while Adamts13+/+ siblings did not. Synovial tissue from Adamts13-/- showed accumulation of NETs. Treatment of DBA/1 J mice, an arthritis-susceptible strain, with well-tolerated doses of rhADAMT13 reduced arthritis incidence and alleviated the severity of arthritis. Mice treated with rhADAMT13 presented less serum interleukin 6 and less bone erosion determined by micro-computed tomography. The effects on arthritis severity were observed both when administering rhADAMTS-13 prophylactically and also when given after arthritis has developed. In both conditions, rhADAMTS-13 reduced VWF and NET deposition on proliferated synovial tissue evaluated by immunoblotting. CONCLUSIONS: Our results demonstrate the inhibitory role of Adamts13 in murine arthritis and the effectiveness of rhADAMTS-13 treatment. Additionally, this study suggests that deposition of VWF in the synovium and subsequent pathogenic NET retention promotes arthritis. Treatment with rhADAMTS-13 provides a potential therapeutic approach targeting inflammation and pro-thrombotic state in arthritis.

The Prominent Role of Hematopoietic Peptidyl Arginine Deiminase 4 in Arthritis: Collagen- and Granulocyte Colony-Stimulating Factor-Induced Arthritis Model in C57BL/6 Mice.

OBJECTIVE: Genome-wide association studies have connected PADI4, encoding peptidylarginine deiminase 4 (PAD4), with rheumatoid arthritis (RA). PAD4 promotes neutrophil extracellular trap (NET) formation. This study was undertaken to investigate the origin of PAD4 and the importance of NET formation in a C57BL/6 mouse model of arthritis. METHODS: To permit the effective use of C57BL/6 mice in the collagen-induced arthritis (CIA) model, we introduced the administration of granulocyte colony-stimulating factor (G-CSF) for 4 consecutive days in conjunction with the booster immunization on day 21. Mice with global Padi4 deficiency (Padi4-/- ) and mice with hematopoietic lineage-specific Padi4 deficiency (Padi4Vav1Cre/+ ) were evaluated in the model. RESULTS: G-CSF significantly increased the incidence and severity of CIA. G-CSF-treated mice showed elevated citrullinated histone H3 (Cit-H3) levels in plasma, while vehicle-treated mice did not. Immunofluorescence microscopy revealed deposition of Cit-H3 in synovial tissue in G-CSF-treated mice. Padi4-/- mice developed less severe arthritis and had lower levels of serum interleukin-6 and plasma Cit-H3, lower levels of Cit-H4 in synovial tissue, and less bone erosion on micro-computed tomography than Padi4+/+ mice in the G-CSF-modified CIA model. Similarly, Padi4Vav1Cre/+ mice developed less severe arthritis, compared with Padi4fl/fl mice, and presented the same phenotype as Padi4-/- mice. CONCLUSION: We succeeded in developing an arthritis model suitable for use in C57BL/6 mice that is fully compliant with high animal welfare standards. We observed a >90% incidence of arthritis in male mice and detectable NET markers. This model, with some features consistent with human RA, demonstrates that hematopoietic PAD4 is an important contributor to arthritis development and may prove useful in future RA research.

What vaccination rate(s) minimize total societal costs after 'opening up' to COVID-19? Age-structured SIRM results for the Delta variant in Australia (New South Wales, Victoria and Western Australia).

Using three age-structured, stochastic SIRM models, calibrated to Australian data post July 2021 with community transmission of the Delta variant, we projected possible public health outcomes (daily cases, hospitalisations, ICU beds, ventilators and fatalities) and economy costs for three states: New South Wales (NSW), Victoria (VIC) and Western Australia (WA). NSW and VIC have had on-going community transmission from July 2021 and were in 'lockdown' to suppress transmission. WA did not have on-going community transmission nor was it in lockdown at the model start date (October 11th 2021) but did maintain strict state border controls. We projected the public health outcomes and the economic costs of 'opening up' (relaxation of lockdowns in NSW and VIC or fully opening the state border for WA) at alternative vaccination rates (70%, 80% and 90%), compared peak patient demand for ICU beds and ventilators to staffed state-level bed capacity, and calculated a 'preferred' vaccination rate that minimizes societal costs and that varies by state. We found that the preferred vaccination rate for all states is at least 80% and that the preferred population vaccination rate is increasing with: (1) the effectiveness (infection, hospitalization and fatality) of the vaccine; (2) the lower is the daily lockdown cost; (3) the larger are the public health costs from COVID-19; (4) the higher is the rate of community transmission before opening up; and (5) the less effective are the public health measures after opening up.