Stomach as the target organ of Rickettsia heilongjiangensis infection in C57BL/6 mice identified by click chemistry.

Spotted fever group rickettsiae (SFGR) are obligate intracellular bacteria that cause spotted fever. The limitations of gene manipulation pose great challenges to studying the infection mechanisms of Rickettsia. By combining bioorthogonal metabolism and click chemistry, we developed a method to label R. heilongjiangensis via azide moieties and achieved rapid pathogen localization without complex procedures. Moreover, we constructed a C57BL/6 mice infection model by simulating tick bites and discovered that the stomach is the target organ of R. heilongjiangensis infection through in vivo imaging systems, which explained the occurrence of gastrointestinal symptoms following R. heilongjiangensis infection in some cases. This study offers a unique perspective for subsequent investigations into the pathogenic mechanisms of SFGR and identifies a potential target organ for R. heilongjiangensis.

A pilot clinical risk model to predict polymyxin-induced nephrotoxicity: a real-world, retrospective cohort study.

OBJECTIVES: Polymyxin-induced nephrotoxicity (PIN) is a major safety concern and challenge in clinical practice, which limits the clinical use of polymyxins. This study aims to investigate the risk factors and to develop a scoring tool for the early prediction of PIN. METHODS: Data on critically ill patients who received intravenous polymyxin B or colistin sulfate for over 24 h were collected. Logistic regression with the least absolute shrinkage and selection operator (LASSO) was used to identify variables that are associated with outcomes. The eXtreme Gradient Boosting (XGB) classifier algorithm was used to further visualize factors with significant differences. A prediction model for PIN was developed through binary logistic regression analysis and the model was assessed by temporal validation and external validation. Finally, a risk-scoring system was developed based on the prediction model. RESULTS: Of 508 patients, 161 (31.6%) patients developed PIN. Polymyxin type, loading dose, septic shock, concomitant vasopressors and baseline blood urea nitrogen (BUN) level were identified as significant predictors of PIN. All validation exhibited great discrimination, with the AUC of 0.742 (95% CI: 0.696-0.787) for internal validation, of 0.708 (95% CI: 0.605-0.810) for temporal validation and of 0.874 (95% CI: 0.759-0.989) for external validation, respectively. A simple risk-scoring tool was developed with a total risk score ranging from -3 to 4, corresponding to a risk of PIN from 0.79% to 81.24%. CONCLUSIONS: This study established a prediction model for PIN. Before using polymyxins, the simple risk-scoring tool can effectively identify patients at risk of developing PIN within a range of 7% to 65%.

IFIH1 variants are associated with generalised epilepsy preceded by febrile seizures.

BACKGROUND: IFIH1 variants have been reported to be associated with immune-related disorders with/without seizures. It is unknown whether IFIH1 variants are associated with common epilepsy without acquired causes and the mechanism underlying phenotypic variation remains elusive. METHODS: Trio-based whole-exome sequencing was performed on patients with febrile seizures or epilepsy with antecedent febrile seizures. Previously reported variants were systematically reviewed to investigate genotype-phenotype associations. RESULTS: Two de novo heterozygous and three biallelic missense variants were identified in five patients with generalised epilepsy with antecedent febrile seizures. The variants were predicted to be damaging by in silico tools and were associated with hydrogen bonding changes to neighbouring amino acids or decreased protein stability. Patients exhibited an early onset age and became seizure-free with favourable outcome. Further analysis revealed that de novo missense variants located in the Hel region resulted in seizures with multiple neurological abnormalities, while those in the pincer domain or C-terminal domain led to seizures with normal neurodevelopment, suggesting a sub-molecular effect. Biallelic missense variants, which were inherited from unaffected parents and presented low allele frequencies in general populations, were associated with seizures without neurological abnormalities. Truncation variants were related to refractory epilepsy and severe developmental delay, suggesting a genotype-phenotype correlation. IFIH1 is predominantly expressed in the neonatal stage and decreases dramatically in the adulthood, which is consistent with the early onset age and favourable outcome of the patients. CONCLUSIONS: IFIH1 variants are potentially associated with generalised epilepsy with antecedent febrile seizures. The sub-molecular implication and genotype-phenotype association help explain phenotype variations of IFIH1 variants.

Cultivation of novel Atribacterota from oil well provides new insight into their diversity, ecology, and evolution in anoxic, carbon-rich environments.

BACKGROUND: The Atribacterota are widely distributed in the subsurface biosphere. Recently, the first Atribacterota isolate was described and the number of Atribacterota genome sequences retrieved from environmental samples has increased significantly; however, their diversity, physiology, ecology, and evolution remain poorly understood. RESULTS: We report the isolation of the second member of Atribacterota, Thermatribacter velox gen. nov., sp. nov., within a new family Thermatribacteraceae fam. nov., and the short-term laboratory cultivation of a member of the JS1 lineage, Phoenicimicrobium oleiphilum HX-OS.bin.34TS, both from a terrestrial oil reservoir. Physiological and metatranscriptomics analyses showed that Thermatribacter velox B11T and Phoenicimicrobium oleiphilum HX-OS.bin.34TS ferment sugars and n-alkanes, respectively, producing H2, CO2, and acetate as common products. Comparative genomics showed that all members of the Atribacterota lack a complete Wood-Ljungdahl Pathway (WLP), but that the Reductive Glycine Pathway (RGP) is widespread, indicating that the RGP, rather than WLP, is a central hub in Atribacterota metabolism. Ancestral character state reconstructions and phylogenetic analyses showed that key genes encoding the RGP (fdhA, fhs, folD, glyA, gcvT, gcvPAB, pdhD) and other central functions were gained independently in the two classes, Atribacteria (OP9) and Phoenicimicrobiia (JS1), after which they were inherited vertically; these genes included fumarate-adding enzymes (faeA; Phoenicimicrobiia only), the CODH/ACS complex (acsABCDE), and diverse hydrogenases (NiFe group 3b, 4b and FeFe group A3, C). Finally, we present genome-resolved community metabolic models showing the central roles of Atribacteria (OP9) and Phoenicimicrobiia (JS1) in acetate- and hydrocarbon-rich environments. CONCLUSION: Our findings expand the knowledge of the diversity, physiology, ecology, and evolution of the phylum Atribacterota. This study is a starting point for promoting more incisive studies of their syntrophic biology and may guide the rational design of strategies to cultivate them in the laboratory. Video Abstract.

Distinct Thalamo-Subcortical Circuits Underlie Painful Behavior and Depression-Like Behavior Following Nerve Injury.

Clinically, chronic pain and depression often coexist in multiple diseases and reciprocally reinforce each other, which greatly escalates the difficulty of treatment. The neural circuit mechanism underlying the chronic pain/depression comorbidity remains unclear. The present study reports that two distinct subregions in the paraventricular thalamus (PVT) play different roles in this pathological process. In the first subregion PVT posterior (PVP), glutamatergic neurons (PVPGlu) send signals to GABAergic neurons (VLPAGGABA) in the ventrolateral periaqueductal gray (VLPAG), which mediates painful behavior in comorbidity. Meanwhile, in another subregion PVT anterior (PVA), glutamatergic neurons (PVAGlu) send signals to the nucleus accumbens D1-positive neurons and D2-positive neurons (NAcD1→D2), which is involved in depression-like behavior in comorbidity. This study demonstrates that the distinct thalamo-subcortical circuits PVPGlu→VLPAGGABA and PVAGlu→NAcD1→D2 mediated painful behavior and depression-like behavior following spared nerve injury (SNI), respectively, which provides the circuit-based potential targets for preventing and treating comorbidity.

3D printing redefines microneedle fabrication for transdermal drug delivery.

Microneedles (MNs) have emerged as an innovative, virtually painless technique for intradermal drug delivery. However, the complex and costly fabrication process has limited their widespread accessibility, especially for individuals requiring frequent drug administration. This study introduces a groundbreaking and cost-effective method for producing MNs utilizing fused deposition modeling (FDM) 3D printing technology to enhance transdermal drug delivery. The proposed fabrication process involves the elongation of molten polylactic acid (PLA) filaments to create meticulously designed conoid and neiloid MNs with smooth surfaces. This study underscores the critical role of printing parameters, particularly extrusion length and printing speed, in determining the shape of the MNs. Notably, the conoid-shaped MNs exhibit exceptional skin-penetrating capabilities. In order to evaluate their effectiveness, the MNs were tested on a polydimethylsiloxane (PDMS) skin model for skin penetration. The results highlight the high potential of 3D-printed MNs for transdermal drug administration. This novel approach capitalizes on the benefits of 3D printing technology to fabricate MNs that hold the promise of transforming painless drug administration for a variety of medical applications.

Lappulaeffusa (Boraginaceae), a new species from Xinjiang, China.

Lappulaeffusa D.H.Liu & W.J.Li, a new species of Boraginaceae from Xinjiang, China, is described and illustrated in this study. The new species is morphologically similar to Lappulahimalayensis and L.tadshikorum. However, it can be distinguished from the compared species by several characteristics, such as: stem single, erect, frequently branched at middle and above, densely spreading hispid, hairs discoid at base; corolla white or blue; fruit compressed, heteromorphic nutlets with two rows of marginal glochids, nutlets acute ovoid, disc narrowly ovate-triangular. The diagnosis of the new species is supported with comprehensive investigation including photographs, detailed description, notes on etymology, distribution and habitat, conservation status, as well as comparisons with morphologically similar species.

Cultural psychological factors in posttraumatic symptom development and expression: a study protocol.

Introduction: Cultural factors were shown to be particularly relevant for the development and expression of posttraumatic stress. Recently, the concept of cultural scripts of trauma has been introduced, which proposes that trauma sequelae elements may be sequentially linked and specifically associated with cultural factors. Furthermore, a cascade model is proposed, including trauma exposure, demographic characteristics, cultural affiliation, and trauma-related value orientations as influencing factors of posttraumatic development. The purpose of this Network Project is to investigate cultural psychological factors that contribute to the expression of posttraumatic stress.Methods: The present Network Project implements a mixed methods approach and will be conducted in 5 different study sites, including Switzerland, Israel, Georgia, China, and East Africa. In sub-study I, the cultural scripts of traumatic stress inventories (CSTIs) will be developed. These scales provide a pool of trauma sequelae elements for each cultural group. For this purpose, focus groups with trauma survivors and trauma experts will be conducted and analysed using qualitative research methods. Sub-study II implements a validation analysis of the CSTIs and the empirical investigation of a cultural cascade model. This quantitative approach will include a larger sample of individuals who experienced traumatic life events.Discussion: This contribution is timely and enriches the knowledge of trauma and culture. Future publications of this Network Project will address trauma sequelae from a cultural perspective and provide diagnostic and psychotherapeutic implications.

This paper presents a Network Project that investigates cultural factors in posttraumatic sequelae.The Network Project encompasses an innovative research design with both qualitative and quantitative methods.New developments in the field of cultural clinical psychology are introduced, including cultural scripts of trauma and a cascade model of cultural factors in posttraumatic symptom expression.

Plant beneficial traits of endophytic bacteria associated with fennel (Foeniculum vulgare Mill.).

In this study, we used 16S rRNA gene sequence analysis to describe the diversity of cultivable endophytic bacteria associated with fennel (Foeniculum vulgare Mill.) and determined their plant-beneficial traits. The bacterial isolates from the roots of fennel belonged to four phyla: Firmicutes (BRN1 and BRN3), Proteobacteria (BRN5, BRN6, and BRN7), Gammaproteobacteria (BRN2), and Actinobacteria (BRN4). The bacterial isolates from the shoot of fennel represented the phyla Proteobacteria (BSN1, BSN2, BSN3, BSN5, BSN6, BSN7, and BSN8), Firmicutes (BSN4, BRN1, and BRN3), and Actinobacteria (BRN4). The bacterial species Bacillus megaterium, Bacillus aryabhattai, and Brevibacterium frigoritolerans were found both in the roots and shoots of fennel. The bacterial isolates were found to produce siderophores, HCN, and indole-3-acetic acid (IAA), as well as hydrolytic enzymes such as chitinase, protease, glucanase, and lipase. Seven bacterial isolates showed antagonistic activity against Fusarium culmorum, Fusarium solani, and Rhizoctonia. solani. Our findings show that medicinal plants with antibacterial activity may serve as a source for the selection of microorganisms that exhibit antagonistic activity against plant fungal infections and may be considered as a viable option for the management of fungal diseases. They can also serve as an active part of biopreparation, improving plant growth.

The Identification and Gene Mapping of Spotted Leaf Mutant spl43 in Rice.

Our study investigates the genetic mechanisms underlying the spotted leaf phenotype in rice, focusing on the spl43 mutant. This mutant is characterized by persistent reddish-brown leaf spots from the seedling stage to maturity, leading to extensive leaf necrosis. Using map-based cloning, we localized the responsible locus to a 330 Kb region on chromosome 2. We identified LOC_Os02g56000, named OsRPT5A, as the causative gene. A point mutation in OsRPT5A, substituting valine for glutamic acid, was identified as the critical factor for the phenotype. Functional complementation and the generation of CRISPR/Cas9-mediated knockout lines in the IR64 background confirmed the central role of OsRPT5A in controlling this trait. The qPCR results from different parts of the rice plant revealed that OsRPT5A is constitutively expressed across various tissues, with its subcellular localization unaffected by the mutation. Notably, we observed an abnormal accumulation of reactive oxygen species (ROS) in spl43 mutants by examining the physiological indexes of leaves, suggesting a disruption in the ROS system. Complementation studies indicated OsRPT5A's involvement in ROS homeostasis and catalase activity regulation. Moreover, the spl43 mutant exhibited enhanced resistance to Xanthomonas oryzae pv. oryzae (Xoo), highlighting OsRPT5A's role in rice pathogen resistance mechanisms. Overall, our results suggest that OsRPT5A plays a critical role in regulating ROS homeostasis and enhancing pathogen resistance in rice.

Type X collagen knockdown inactivate ITGB1/PI3K/AKT to suppress chronic unpredictable mild stress-stimulated triple-negative breast cancer progression.

Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer, has a poor prognosis and limited access to efficient targeted treatments. Chronic unpredictable mild stress (CUMS) is highly risk factor for TNBC occurrence and development. Type X collagen (COL10A1), a crucial protein component of the extracellular matrix, ranks second among all aberrantly expressed genes in TNBC, and it is significantly up-regulated under CUMS. Nevertheless, the impact of CUMS and COL10A1 on TNBC, along with the underlying mechanisms are still unclear. In this research, we studied the effect of CUMS-induced norepinephrine (NE) elevation on TNBC, and uncovered that it notably enhanced TNBC cell proliferation, migration, and invasion in vitro, and also fostering tumor growth and lung metastasis in vivo. Additionally, our investigation found that COL10A1 directly interacted with integrin subunit beta 1 (ITGB1), then activates the downstream PI3K/AKT signaling pathway, thereby promoting TNBC growth and metastasis, while it was reversed by knocking down of COL10A1 or ITGB1. Our study demonstrated that the TNBC could respond to CUMS, and advocate for COL10A1 as a pivotal therapeutic target in TNBC treatment.

A Report of Two Cases of Meningoencephalitis Caused by Streptococcus intermedius.

Objective: In this paper, we analyzed the clinical data of patients with meningoencephalitis caused by Streptococcus intermedius to understand better the clinical characteristics of the disease and recommend auxiliary diagnostic mode as well as treatment experience. Methods: We reviewed the clinical data of two patients admitted to our department in 2019 with meningoencephalitis caused by S. intermedius. Results: Two female patients were examined, one of whom had a history of radiotherapy for nasopharyngeal carcinoma while the other had no underlying disease. These two patients were admitted with symptoms of meningoencephalitis. Cerebrospinal fluid examinations revealed elevated levels of leukocytes and protein. After treatment with meropenem, the condition improved for a brief time, but then worsened with a decline in mental status and limb movement. Blood and cerebrospinal fluid cultures demonstrated the absence of pathogenic bacteria, while genome sequencing of cerebrospinal fluids revealed the presence of S. intermedius. Cranial magnetic resonance imaging revealed multiple cerebral abscesses (CAs). After coadministration of linezolid as an anti-infective, clinical symptoms gradually improved, and the CAs shrank on follow-up imaging. The condition exhibited a pattern of improvement-deterioration-improvement. Conclusion: Meningoencephalitis caused by S. intermedius is complex and prone to fluctuation and formation of multiple CAs. The definitive clinical diagnosis of this disease can be aided by genome sequencing technology, and early clarification of the etiology combined with the use of potent antibiotics is effective.

Association between protein intake, serum albumin and blood eosinophil in US asthmatic adults.

Background: Presently, numerous studies have indicated that protein consumption and levels of blood albumin serve as important biomarkers for a range of respiratory illnesses. However, there have been few investigations into the correlation between protein consumption, serum albumin, and asthma. Methods: Our analysis incorporated 2509 asthmatics from the 2011-2018 NHANES dataset. The investigation employed three linear regression models and XGBoost model to investigate the potential link between protein intake, serum albumin levels, and blood eosinophil counts (BEOC) in patients with asthma. The trend test, generalized additive model (GAM), and threshold effect model were utilized to validate this correlation. As well, we undertook stratified analyses to look at the correlation of serum albumin with BEOC among distinct populations. Results: In the univariable regression model, which did not account for any covariates, we observed a positive correlation between protein intake and BEOC. However, univariable and multivariable regression analyses all suggested a negative connection of serum albumin with BEOC in asthma populations. In Model C, which took into account all possible factors, BEOC dropped by 2.82 cells/uL for every unit increase in serum albumin (g/L). Additionally, the GAM and threshold effect model validated that serum albumin and BEOC showed an inverted U-shaped correlation. Conclusion: Our investigation discovered there was no independent link between asthmatics' protein intake and BEOC. However, we observed an inverted U-shaped relationship between serum albumin levels and BEOC, suggesting a possible relationship between the overall nutritional status of asthmatics and immune system changes. Our findings provide new directions for future research in the field of asthma management and therapy.

C-reactive protein is a predictor for lower-extremity deep venous thrombosis in patients with primary intracerebral hemorrhage.

OBJECTIVE: Our study aimed to determine whether there exists an association between low-grade systemic inflammation, as measured by serum C-reactive protein (CRP), and the risk of lower-extremity deep venous thrombosis (LEDVT) in patients with primary intracerebral hemorrhage (ICH). METHODS: This observational study was retrospectively conducted on patients with primary ICH who were presented to two tertiary medical centers between January 2021 and August 2022. The primary outcome was detecting LEDVT occurrence within 14 days from the onset of the acute ICH episode. Weighted logistic regression and restricted cubic spline models were employed to estimate the association between CRP and LEDVT following 1:1 propensity score matching (PSM). RESULTS: Of the 538 patients with primary ICH who met the inclusion criteria, 76 (14.13%) experienced LEDVT. Based on the cut-off levels of CRP measured upon admission from the receiver operating characteristic (ROC) curve, patients with primary ICH were categorized into two groups: (i) CRP < 1.59 mg/L and (ii) CRP ≥ 1.59 mg/L. After 1:1 PSM, the LEDVT events occurred in 24.6% of patients with CRP ≥ 1.59 mg/L and 4.1% of patients with CRP < 1.59 mg/L (P < 0.001). ROC curve revealed the area under the ROC curve of 0.717 [95% confidence interval (CI) 0.669-0.761, P < 0.001] for CRP to predict LEDVT with a sensitivity of 85.71% and specificity of 56.29%. After adjusting for all confounding variables, the occurrence of LEDVT in ICH patients with higher CRP levels (≥ 1.59 mg/L) was 10.8 times higher compared to those with lower CRP levels (95% CI 4.5-25.8, P < 0.001). A nonlinear association was observed between CRP and an increased risk of LEDVT in the fully adjusted model (P for overall < 0.001, P for nonlinear = 0.001). The subgroup results indicated a consistent positive link between CRP and LEDVT events following primary ICH. CONCLUSIONS: Higher initial CRP levels (CRP as a dichotomized variable) in patients with primary ICH are significantly associated with an increased risk of LEDVT and may help identify high-risk patients with LEDVT. Clinicians should be vigilant to enable early and effective intervention in patients at high risk of LEDVT.

Numerical investigation on the impact of different coronary aneurysms morphologies on thrombus formation and hemodynamics: a comparative study.

Coronary artery aneurysms (CAAs) are morphologically classified as saccular and fusiform. There is still a great deal of clinical controversy as to which types of CAA are more likely to cause thrombosis. Therefore, the main objective of this study was to evaluate the trend of thrombus growth in CAAs with different morphologies and to assess the risk of possible long-term complications based on hemodynamic parameters. Utilizing computed tomography angiography (CTA) data from eight healthy coronary arteries, two distinct morphologies of coronary artery aneurysms (CAAs) were reconstructed. Distribution of four wall shear stress (WSS)-based indicators and three helicity indicators was analyzed in this study. Meanwhile, a thrombus growth model was introduced to analyze the thrombus formation in CAAs with different morphologies. The research results showed the distribution of most WSS indicators between saccular and fusiform CAAs was not statistically significant. However, due to the presence of a more pronounced helical flow pattern, irregular helical flow structure and longer time of flow stagnation in saccular CAAs during the cardiac cycle, the mean and maximum relative residence time (RRT) were significantly higher in saccular CAAs than in fusiform CAAs (P < 0.05). This may increase the risk of saccular coronary arteries leading to aneurysmal dilatation or even rupture. Although the two CAAs had similar rates of thrombosis, fusiform CAAs may more early cause obstruction of the main coronary flow channel where the aneurysm is located due to thrombosis growth. Thus, the risk of thrombosis in fusiform coronary aneurysms may warrant greater clinical concern.

[Effects of litter thickness on natural regeneration of Larix principis-rupprechtii plantations]. / 枯落物厚度对华北落叶松人工林天然更新的影响.

In this study, we explored the thickness influence of undecomposed litter layer and semi-decomposed litter layer on the natural regeneration in an artificial pure forest of Larix principis-rupprechtii in the forest area of Guandi Mountain. We divided the litter into an undecomposed layer and a semi-decomposed layer, which was further divided into eight groups based on the thickness. The results showed that when the thickness of undecomposed layer was 0.32-0.83 cm, and that of semi-decomposed layer was 0.18-0.89 cm, the regeneration index was larger (≥0.15), and the regeneration was better. When the thickness of undecomposed layer was more than 1.1 cm and that of semi-decomposed layer was more than 0.5 cm, the regeneration index was smaller (≤0.07), and the rege-neration of understory was worse. Results of redundancy analysis showed that the undecomposed layer thickness of litter had a high and stable explanatory ability for natural regeneration, with a contribution rate of 38.7%, while the semi-decomposed layer thickness had no significant effect on natural regeneration. Structural equation modeling revealed that the thickness of undecomposed layer of litter increased the mechanical resistance to seed germination which had a negative direct effect on natural regeneration (-0.617), and a positive indirect effect on natural rege-neration by influencing the content of alkali-hydrolyzed nitrogen and available phosphorus (+0.178). The combined effects (-0.439) showed an inhibitory effect on the natural regeneration. In conclusion, the thickness of undecomposed layer of litter under L. principis-rupprechtii was most closely related to natural regeneration, and the thickness of semi-decomposed layer had a minimal effect on natural regeneration.

AKI-Pro score for predicting progression to severe acute kidney injury or death in patients with early acute kidney injury after cardiac surgery.

BACKGROUND: No reliable clinical tools exist to predict acute kidney injury (AKI) progression. We aim to explore a scoring system for predicting the composite outcome of progression to severe AKI or death within seven days among early AKI patients after cardiac surgery. METHODS: In this study, we used two independent cohorts, and patients who experienced mild/moderate AKI within 48 h after cardiac surgery were enrolled. Eventually, 3188 patients from the MIMIC-IV database were used as the derivation cohort, while 499 patients from the Zhongshan cohort were used as external validation. The primary outcome was defined by the composite outcome of progression to severe AKI or death within seven days after enrollment. The variables identified by LASSO regression analysis were entered into logistic regression models and were used to construct the risk score. RESULTS: The composite outcome accounted for 3.7% (n = 119) and 7.6% (n = 38) of the derivation and validation cohorts, respectively. Six predictors were assembled into a risk score (AKI-Pro score), including female, baseline eGFR, aortic surgery, modified furosemide responsiveness index (mFRI), SOFA, and AKI stage. And we stratified the risk score into four groups: low, moderate, high, and very high risk. The risk score displayed satisfied predictive discrimination and calibration in the derivation and validation cohort. The AKI-Pro score discriminated the composite outcome better than CRATE score, Cleveland score, AKICS score, Simplified renal index, and SRI risk score (all P < 0.05). CONCLUSIONS: The AKI-Pro score is a new clinical tool that could assist clinicians to identify early AKI patients at high risk for AKI progression or death.

The Microbiome Protocols eBook initiative: Building a bridge to microbiome research.

The Microbiome Protocols eBook (MPB) serves as a crucial bridge, filling gaps in microbiome protocols for both wet experiments and data analysis. The first edition, launched in 2020, featured 152 meticulously curated protocols, garnering widespread acclaim. We now extend a sincere invitation to researchers to participate in the upcoming 2nd version of MPB, contributing their valuable protocols to advance microbiome research.

Epoxidized Soybean Oleic Acid/Oligomeric Poly(lactic acid)-Grafted Nano-Hydroxyapatite and Its Role as a Filler in Poly(L-lactide) for Potential Bone Fixation Application.

One of the most effective strategies for modifying the surface properties of nano-fillers and enhancing their composite characteristics is through polymer grafting. In this study, a coprecipitation method was employed to modify hydroxyapatite (HAP) with epoxidized soybean oleic acid (ESOA), resulting in ESOA-HAP. Subsequently, oligomeric poly(lactic acid) (OPLA) was grafted onto the surface of ESOA-HAP, yielding OPLA-ESOA-HAP. HAP, ESOA-HAP, and OPLA-ESOA-HAP were comprehensively characterized. The results demonstrate the progressive grafting of ESOA and OPLA onto the surface of HAP, resulting in enhanced hydrophobicity and improved dispersity in organic solvent for OPLA-ESOA-HAP compared to HAP. The vitality and adhesion of Wistar rat mesenchymal stem cells (MSCs) were assessed using HAP and modified HAP materials. Following culture with MSCs for 72 h, the OPLA-ESOA-HAP showed an inhibition rate lower than 23.0% at a relatively high concentration (1.0 mg/mL), which is three times lower compared to HAP under similar condition. The cell number for OPLA-ESOA-HAP was 4.5 times higher compared to HAP, indicating its superior biocompatibility. Furthermore, the mechanical properties of the OPLA-ESOA-HAP/PLLA composite almost remained unaltered ever after undergoing two stages of thermal processing involving melt extrusion and inject molding. The increase in the biocompatibility and relatively high mechanical properties render OPLA-ESOA-HAP/PLLA a potential material for the biodegradable fixation system.