The therapeutic potential of curculigoside in poststroke depression: a focus on hippocampal neurogenesis and mitochondrial function.

OBJECTIVES: To investigate the effects and mechanism of curculigoside against poststroke depression (PSD). METHODS: In vivo, a PSD rat model was created by combining bilateral common carotid artery occlusion and chronic unpredictable mild stress stimulations. After 4-week modeling and intragastrically administration of curculigoside, the effects of curculigoside on behavior, hippocampal neurogenesis, and hippocampal mitochondrial oxidative phosphorylation (OxPhos) were investigated. In vitro, PSD-like primary neural stem cells (NSCs) model was established by oxygen-glucose deprivation/recovery (OGD/R) combing high-corticosterone (CORT) concentration, followed by treatment with curculigoside. The investigation subsequently examined the impact of curculigoside on mitochondrial OxPhos, proliferation, and differentiation of NSCs under OGD/R + CORT conditions. KEY FINDINGS: In vivo, PSD rats showed significantly depressive behaviors, dysfunctional neurogenesis in hippocampus, as well as decreased hippocampus adenosine triphosphate (ATP) levels, reduced electron transport chain complexes activity, and downregulates mitochondrial transcription factor A (TFAM) and PPAR-gamma coactivator 1 alpha (PGC-1α) expression in hippocampus. In vitro, OGD/R +CORT significantly injured the proliferation and differentiation, as well as impaired the mitochondrial OxPhos in NSCs. Curculigoside treatment was effective in improving these abnormal changes. CONCLUSION: Curculigoside may repair hippocampal neurogenesis in PSD rats by enhancing hippocampal mitochondrial OxPhos, and has shown a great potential for anti-PSD.

Safety evaluation of outpatient vs inpatient unicompartmental knee arthroplasty: a systematic review and meta-analysis.

PURPOSE: This systematic review and meta-analysis aimed to evaluate the safety of outpatient and inpatient Unicompartmental Knee Arthroplasty (UKA) based on the incidence of adverse events. METHOD: A systematic search of the literature was performed in October 2022 on PubMed, Web of Science, Cochrane library, and Embase. The Meta package for R was used to perform the meta-analysis. RESULT: Five studies with a total of 26,301 patients were included. 5813 patients (22.1%) were treated with outpatient UKA, and 20,488 patients (77.9%) were treated with inpatient UKA. There were no statistically significant differences in the incidence of total complications (RR = 1.36, 95% CI = 0.64-2.89, Z = 0.79, P = 0.43), readmission (RR = 1.02, 95% CI = 0.40-2.60, Z = 0.05, P = 0.96), and venous thrombosis (RR = 1.43, 95% CI = 0.96-2.11, Z = 1.78, P = 0.08). Incidence rates were lower in outpatient UKA regarding urinary tract infection (RR = 1.48, 95% CI = 1.07-2.04, Z = 2.40, P = 0.02), pulmonary embolus (RR = 7.48, 95% CI = 1.80-31.17, Z = 2.76, P < 0.01), and transfusion (RR = 2.77, 95% CI = 1.63-4.71, Z = 3.78, P < 0.01). CONCLUSION: In summary, outpatient UKA shows lower incidences of hospital-acquired complications such urinary tract infection, pulmonary embolus, and transfusion. It's worth noting that the incidences of total complications, readmission, and venous thrombosis in outpatient UKA were not higher than the incidences of inpatient UKA, suggestting that outpatient UKA can be considered a safe alternative to inpatient UKA.

A Deep Learning Model Enhances Clinicians' Diagnostic Accuracy to More Than 96% for Anterior Cruciate Ligament Ruptures on Magnetic Resonance Imaging.

PURPOSE: To develop a deep learning model to accurately detect anterior cruciate ligament (ACL) ruptures on magnetic resonance imaging (MRI) and to evaluate its effect on the diagnostic accuracy and efficiency of clinicians. METHODS: A training dataset was built from MRIs acquired from January 2017 to June 2021, including patients with knee symptoms, irrespective of ACL ruptures. An external validation dataset was built from MRIs acquired from January 2021 to June 2022, including patients who underwent knee arthroscopy or arthroplasty. Patients with fractures or prior knee surgeries were excluded in both datasets. Subsequently, a deep learning model was developed and validated using these datasets. Clinicians of varying expertise levels in sports medicine and radiology were recruited, and their capacities in diagnosing ACL injuries in terms of accuracy and diagnosing time were evaluated both with and without artificial intelligence (AI) assistance. RESULTS: A deep learning model was developed based on the training dataset of 22,767 MRIs from 5 centers and verified with external validation dataset of 4,086 MRIs from 6 centers. The model achieved an area under the receiver operating characteristic curve of 0.987 and a sensitivity and specificity of 95.1%. Thirty-eight clinicians from 25 centers were recruited to diagnose 3,800 MRIs. The AI assistance significantly improved the accuracy of all clinicians, exceeding 96%. Additionally, a notable reduction in diagnostic time was observed. The most significant improvements in accuracy and time efficiency were observed in the trainee groups, suggesting that AI support is particularly beneficial for clinicians with moderately limited diagnostic expertise. CONCLUSIONS: This deep learning model demonstrated expert-level diagnostic performance for ACL ruptures, serving as a valuable tool to assist clinicians of various specialties and experience levels in making accurate and efficient diagnoses. LEVEL OF EVIDENCE: Level III, retrospective comparative case series.

Measurement of non-invasive cardiac output during cycling exercise in ischemic stroke inpatients: A pilot study.

BACKGROUND: Cardiac dysfunction accompanies acute ischemic stroke and affects the effective implementation of early rehabilitation interventions. There is a lack of reference hemodynamic data on cardiac function in the subacute phase of ischemic stroke. OBJECTIVE: In this study, we aimed to identify appropriate cardiac parameters for exercise training utilizing a pilot study. METHODS: We used a transthoracic electrical bioimpedance non-invasive cardiac output measurement (NICOM) device to monitor cardiac function in real time for two groups [i.e., subacute ischemic stroke inpatients group (n= 10) and healthy control group (n= 11)] using a cycling exercise experiment. The parameters of both groups were compared to highlight the cardiac dysfunction in the subacute phase in patients with ischemic stroke. RESULTS: We considered stroke volume index (SVI) and systemic vascular resistance index (SVRi) as the primary outcomes, and there was significant intragroup difference (stroke group: P< 0.001; control group: P< 0.001, using one-way ANOVA) and significant intergroup difference at each individual time segment (P< 0.01, using independent t-test). Among the secondary outcomes, i.e., cardiac index (CI), ejection fraction (EF), end-diastolic volume (EDV), and cardiac contraction index (CTI), we found significant intergroup differences in CI, EF, and CTI scores (P< 0.01, using independent t-test). Significant interaction with respect to time and group were seen only in the SVRi and CI scores (P< 0.01, using two-way ANOVA). There was no significant inter- or intra-group differences in EDV scores. CONCLUSION: SVRI, SVI, and CI values highlight cardiac dysfunction in stroke patients the most. At the same time, these parameters suggest that cardiac dysfunction in stroke patients may be closely related to the increased peripheral vascular resistance caused by infarction and the limitation of myocardial systolic function.

Combined analysis of imaging tumor capsule with imaging tumor size guides the width of resection margin for solitary hepatocellular carcinoma.

BACKGROUND: The optimal width of resection margin (RM) for hepatocellular carcinoma (HCC) remains controversial. This study aimed to investigate the value of imaging tumor capsule (ITC) and imaging tumor size (ITS) in guiding RM width for patients with HCC. METHODS: Patients who underwent hepatectomy for HCC in our center were retrospectively reviewed. ITC (complete/incomplete) and ITS (≤ 3 cm/> 3 cm) were assessed by preoperative magnetic resonance imaging (MRI). Using subgroup analyses based on ITC and ITS, the impact of RM width [narrow RM (< 5 mm)/wide RM (≥ 5 mm)] on recurrence-free survival (RFS), overall survival (OS), and RM recurrence was analyzed. RESULTS: A total of 247 patients with solitary HCC were included. ITC and ITS were independent predictors for RFS and OS in the entire cohort. In patients with ITS ≤ 3 cm, neither ITC nor RM width showed a significant impact on prognosis, and the incidence of RM recurrence was comparable between the narrow RM and wide RM groups (15.6% vs. 4.3%, P = 0.337). In patients with ITS > 3 cm and complete ITC, the narrow RM group exhibited comparable RFS, OS, and incidence of RM recurrence with the wide RM group (P = 0.606, 0.916, and 0.649, respectively). However, in patients with ITS > 3 cm and incomplete ITC, the wide RM group showed better RFS and OS and a lower incidence of RM recurrence compared with the narrow RM group (P = 0.037, 0.018, and 0.046, respectively). CONCLUSIONS: As MRI-based preoperative markers, conjoint analysis of ITC with ITS aids in determining RM width for solitary HCC patients. Narrow RM is applicable in patients with ITS ≤ 3 cm regardless of ITC status and in those with ITS > 3 cm and complete ITC. Wide RM is preferred in those with ITS > 3 cm and incomplete ITC.

Unsupervised Machine Learning-Based Analysis of Clinical Features, Bone Mineral Density Features and Medical Care Costs of Rotator Cuff Tears.

PURPOSE: We aim to present unsupervised machine learning-based analysis of clinical features, bone mineral density (BMD) features, and medical care costs of Rotator cuff tears (RCT). PATIENTS AND METHODS: Fifty-three patients with RCT were reviewed, the clinical features, BMD features, and medical care costs were collected and analyzed by descriptive statistics. Furtherly, unsupervised machine learning (UML) algorithm was used for dimensionality reduction and cluster analysis of the RCT data. RESULTS: There were 26 males and 27 females. The patients were divided into four subgroups using the UML algorithm. There were significant differences among four subgroups regarding trauma exposure, full-thickness supraspinatus tendon tears, infraspinatus tendon tear, subscapularis tendon tear, BMD distribution, medial row anchors, lateral row anchors, total medical care costs, and consumables costs. We observed the highest frequency of trauma exposure, infraspinatus tendon tear, subscapularis tendon tear, osteoporosis, the highest number of medial row anchors, lateral row anchors, total medical care costs, and consumables costs in subgroup II. CONCLUSION: The unsupervised machine learning-based analysis of RCT can provide clinically meaningful classification, which shows good interpretability and contribute to a better understanding of RCT. The significance of the results is limited due to the small number of samples, a larger follow-up study is needed to confirm the encouraging results.

Postoperative Bone Marrow Lesions (BMLs) Are Associated with Pain Severity in Patients Undergoing Open Wedge High Tibial Osteotomy (OWHTO).

The purpose of the study was to investigate the relationship between postoperative bone marrow lesions (BMLs) and pain severity in patients undergoing open wedge high tibial osteotomy (OWHTO). We reviewed the patients undergoing OWHTO between April 2018 and April 2020. The demographic and clinical data of patients were collected. Clinically, VAS and Knee injury and Osteoarthritis Outcome Score (KOOS) were used to assess pain level and functional outcomes of patients. The MRI Osteoarthritis Knee Score (MOAKS) was used to assess the total BMLs size in medial tibiofemoral (MTF), lateral tibiofemoral (LTF), and patellofemoral (PF) joints. 98 patients were enrolled in the study, including 57 male and 41 female patients. The VAS scores improved significantly from 6.1 ± 0.8 to 1.5 ± 0.9 (p < 0.001), and all subscales of KOOS improved significantly after surgery (p < 0.001). There were no significant differences between the pre- and postoperative total BML size of PF and LTF joints (p > 0.05). We observed significant improvements in the total BML size of MTF joint (p < 0.001). The VAS scores and KOOS pain scores improved better in patients without postoperative MTF joint BMLs (p < 0.001). Postoperative MTF joint BMLs were correlated with postoperative VAS (p < 0.001) and KOOS pain (p < 0.001). Our study demonstrates that MTF joint BMLs improved significantly after OWTHO. We confirmed that the presence of postoperative MTF joint BMLs are strongly associated with pain severity. The greater the improvement in postoperative MTF joint BMLs, the less pain. Our findings provide valuable understandings of OWHTO in the treatment of knee osteoarthritis (KOA) and potential future directions for KOA treatment approaches.

A Novel Application of Unsupervised Machine Learning and Supervised Machine Learning-Derived Radiomics in Anterior Cruciate Ligament Rupture.

PURPOSE: We aim to present an unsupervised machine learning application in anterior cruciate ligament (ACL) rupture and evaluate whether supervised machine learning-derived radiomics features enable prediction of ACL rupture accurately. PATIENTS AND METHODS: Sixty-eight patients were reviewed. Their demographic features were recorded, radiomics features were extracted, and the input dataset was defined as a collection of demographic features and radiomics features. The input dataset was automatically classified by the unsupervised machine learning algorithm. Then, we used a supervised machine learning algorithm to construct a radiomics model. The t-test and least absolute shrinkage and selection operator (LASSO) method were used for feature selection, random forest and support vector machine (SVM) were used as machine learning classifiers. For each model, the sensitivity, specificity, accuracy, and the area under the curve (AUC) of receiver operating characteristic (ROC) curves were calculated to evaluate model performance. RESULTS: In total, 5 demographic features were recorded and 106 radiomics features were extracted. By applying the unsupervised machine learning algorithm, patients were divided into 5 groups. Group 5 had the highest incidence of ACL rupture and left knee involvement. There were significant differences in left knee involvement among the groups. Forty-three radiomics features were extracted using t-test and 7 radiomics features were extracted using LASSO method. We found that the combination of LASSO selection method and random forest classifier has the highest sensitivity, specificity, accuracy, and AUC. The 7 radiomics features extracted by LASSO method were potential predictors for ACL rupture. CONCLUSION: We validated the clinical application of unsupervised machine learning involving ACL rupture. Moreover, we found 7 radiomics features which were potential predictors for ACL rupture. The study indicated that radiomics could be a valuable method in the prediction of ACL rupture.

Tranexamic Acid Is Beneficial to Patients Undergoing Open-Wedge High Tibial Osteotomy.

The purpose of this study was to investigate the efficacy of tranexamic acid (TXA) in patients undergoing open-wedge high tibial osteotomy (OWHTO). Patients from August 2018 to May 2020 were retrospectively studied. Clinical data were obtained including gender, age, height, weight, body mass index (BMI), smoking, alcohol consumption, hypertension, diabetes, history of aspirin, prepostoperative hematocrit (Hct) and hemoglobin (Hb), thrombotic events, blood transfusion requirement, hospital length of stay, size of osteotomy gap, and wound complications such as wound hematoma and infection. 52 patients were enrolled in the tranexamic acid group (TA group), and 48 patients were enrolled in the nontranexamic acid group (NTA group); there were no significant differences between both groups in terms of gender, age, BMI, preoperative Hb, size of osteotomy gap, incidence of smoking, alcohol consumption, hypertension, diabetes, history of aspirin, thrombotic events, blood transfusion requirement, and wound hematoma and infection. The mean hospital length of stay was 9.4 ± 1.0 days in the TA group and 11.0 ± 1.2 days in the NTA group (P < 0.001), the blood loss was 296.0 ± 128.7 ml in the TA group and 383.3 ± 181.3 ml in the NTA group (P < 0.05), and the postoperative Hb level was 120.8 ± 15.0 g/l in the TA group and 109.5 ± 13.8 g/l in the NTA group (P < 0.001). In conclusion, the administration of TXA is beneficial to patients undergoing OWHTO via decreasing hospital length of stay, reducing blood loss, and maintaining higher postoperative Hb levels.

Patient Characteristics Related to Blood Loss in High Tibial Osteotomy in Novel Multiple Linear Regression Analysis.

The purpose of the study was to identify patient characteristics related to blood loss following high tibial osteotomy (HTO). We evaluated 48 patients undergoing HTO from August 2018 to August 2019. The data of 48 patients were collected, including gender, age, height, weight, body mass index (BMI), smoking, alcohol consumption, hypertension, diabetes, history of aspirin, and pre-postoperative hematocrit (Hct). Multiple linear regression analysis was used to analyze the risk factors related to blood loss in HTO. The mean age of patients was 56.6 ± 10.2 years, including 22 males and 26 females. The mean BMI was 28.5 ± 4.2 kg/m2, and the mean blood loss volume was 383.3 ± 181.3 mL, 13 patients with smoking (27.1%), 15 patients with alcohol consumption (31.3%), 23 patients with hypertension (47.9%), 10 patients with diabetes mellitus (20.8%), and 12 patients with history of aspirin (25.0%). Multiple linear regression model suggested alcohol consumption and BMI were associated with blood loss in HTO, R 2 = 0.451, F(9, 38) = 3.462 (P < 0.05). Our study indicates that alcohol consumption and BMI are important risk factors related to blood loss in HTO.

Highly Efficient and Selective Dissolution Separation of Fission Products by an Ionic Liquid [Hbet][Tf2N]: A New Approach to Spent Nuclear Fuel Recycling.

Here, we propose the use of carboxyl-functionalized ionic liquid, [Hbet][Tf2N], to separate the fission products from spent nuclear fuels. This innovative method allows the selective dissolution of neutron poisons, lanthanides oxide, as well as some fission products with high yield, leaving most of the UO2 matrix and minor actinides behind in the spent nuclear fuel and accomplishing the actinides recovery as a group. Water-saturated [Hbet][Tf2N] can dissolve lanthanides oxide from simulated spent nuclear fuel with a dissolution ratio of 100% at 40 °C. However, the dissolution of uranium is almost negligible (<1%) under the same conditions. This big difference in dissolution provides a novel separation approach to spent nuclear fuel recycling and may open new perspectives for spent nuclear fuel reprocessing. The recovery of Nd and U from metal-loaded ionic liquids and the recyclability of the ionic liquid [Hbet][Tf2N] have also been investigated. Furthermore, a U/ x value related to the lattice energy U of metal compound M xO y is used to elaborate the solubility. This work represents the first case for efficient fission products removal by selective dissolution, avoiding the complete dissolution of spent nuclear fuel, the producing of the large high-level radioactive waste, and reducing environmental hazards.

Baicalin Attenuates Joint Pain and Muscle Dysfunction by Inhibiting Muscular Oxidative Stress in an Experimental Osteoarthritis Rat Model.

Osteoarthritis (OA) is the most common degenerative joint disease, and causes major pain and disability in adults. It has been reported that muscle weakness and inflammation contribute to osteoarthritis development and progression. Oxidative stress plays important roles in muscle dysfunction and inflammation in osteomyelitis. Baicalin, the major active constituent of the isolated root of Scutellarialateriflora Georgi, has been shown to have anti-oxidative and anti-inflammatory effects. In this study, we evaluated the potential effects of baicalin on osteoarthritis. We established experimental osteoarthritis rat model, applied baicalin to the rats, and then explored the potential protective effect of baicalin on osteoarthritis severity, muscle dysfunction, and oxidative stress. Baicalin alleviated severity of OA in rats. Baicalin application attenuated muscle dysfunction in OA rats by increasing citrate synthase activity, myosin heavy chain IIa expression, and decreasing interleukin 6 production. Baicalin decreased muscular reactive oxygen species generation in OA rats. Baicalin inhibited nuclear factor erythroid-derived 2-like 2 expression in OA rats. Baicalin attenuated osteoarthritis in rat by inhibiting oxidative stress.

Genetic diversity and phylogenetic analysis of EG95 sequences of Echinococcus granulosus: Implications for EG95 vaccine application.

OBJECTIVE: To analyse the genetic variability of EG95 sequences and provide guidance for EG95 vaccine application against Echinococcus granulosus (E. granulosus). METHODS: We analysed EG95 polymorphism by collecting total 97 different E. granulosus isolates from 12 different host species that originated from 10 different countries. Multiple sequence alignments and the homology were performed by Lasergene 1 (DNASTAR Inc., Madison, WI), and the phylogenetic analysis was performed by using MEGA5.1 (CEMI, Tempe, AZ, USA). In addition, linear and conformational epitopes were analysed, including secondary structure, NXT/S glycosylation, fibronectin type III (FnIII) domain and glycosylphosphatidylinositol anchor signal (GPI-anchor). The secondary structure was predicted by PSIPRED method. RESULTS: Our results indicated that most isolates overall shared 72.6-100% identity in EG95 gene sequence with the published standard EG95 sequence, X90928. However, EG95 gene indeed has polymorphism in different isolates. Phylogenetic analysis showed that different isolates could be divided into three subgroups. Subgroup 1 contained 87 isolates while Subgroup 2 and Subgroup 3 consisted of 3 and 7 isolates, respectively. Four sequences cloned from oncosphere shared a high identity with the parental sequence of the current vaccine, X90928, and they belonged to Subgroup 1. However, in comparison to X90928, several amino acid mutations occurred in most isolates besides oncosphere, which potentially altered the immunodominant linear epitopes, glycosylation sites and secondary structures in EG95 genes. All these variations might change their previous antigenicity and thereby affecting the efficacy of current EG95 vaccine. CONCLUSIONS: This study reveals the genetic variability of EG95 sequences in different E. granulosus isolates, and proposed that more vaccination trials would be needed to test the effectiveness of current EG95 vaccine against distinct isolates in different countries.

Bioinformatic prediction of the epitopes of Echinococcus granulosus antigen 5.

The aim of the present study was to predict and analyze the secondary structure, and B and T cell epitopes of Echinococcus granulosus antigen 5 (Ag5) using online software in order to investigate its immunogenicity and preliminarily evaluate its potential as an effective antigen peptide vaccine for cystic echinococcosis. The PortParam program was used to analyze molecular weight, the theoretical isoelectric point, instability index and other physicochemical properties. The secondary structure of the Ag5 protein was predicted using Self-Optimized Prediction method With Alignment and the tertiary structure of the Ag5 protein was predicted using 3DLigandSite together with Center for Biological Sequence Analysis Prediction Servers. Furthermore, the Immune Epitope Database software was used to predict B cell epitopes, and T cell epitopes were predicted with the BioInformatics and Molecular Analysis Section and SYFPEITHI programs. The results demonstrated that α-helixes, ß-turns, random coils and extended strands account for 23.35, 10.95, 41.32, and 24.38% of the secondary structure of the Ag5 protein, respectively. Ten potential B cell epitopes of Ag5 were identified as the amino acids sequences 27-39, 70-80, 117-130, 146-168, 250-262, 284-293, 339-349, 359-371, 403-412 and 454-462, and seven potential T cell epitopes were identified as the amino acid sequences 52-60, 57-65, 182-190, 231-239, 273-281, 318-326 and 467-475. Thus, ten B cell epitopes and seven T cell epitopes were identified on Ag5, suggesting the strong immunogenicity of this protein, which could be applied to design antigen peptide vaccines for echinococcosis.

Reduced Staphylococcus aureus biofilm formation in the presence of chitosan-coated iron oxide nanoparticles.

Staphylococcus aureus can adhere to most foreign materials and form biofilm on the surface of medical devices. Biofilm infections are difficult to resolve. The goal of this in vitro study was to explore the use of chitosan-coated nanoparticles to prevent biofilm formation. For this purpose, S. aureus was seeded in 96-well plates to incubate with chitosan-coated iron oxide nanoparticles in order to study the efficiency of biofilm formation inhibition. The biofilm bacteria count was determined using the spread plate method; biomass formation was measured using the crystal violet staining method. Confocal laser scanning microscopy and scanning electron microscopy were used to study the biofilm formation. The results showed decreased viable bacteria numbers and biomass formation when incubated with chitosan-coated iron oxide nanoparticles at all test concentrations. Confocal laser scanning microscopy showed increased dead bacteria and thinner biofilm when incubated with nanoparticles at a concentration of 500 µg/mL. Scanning electron microscopy revealed that chitosan-coated iron oxide nanoparticles inhibited biofilm formation in polystyrene plates. Future studies should be performed to study these nanoparticles for anti-infective use.

Staphylococcus aureus supernatant induces the release of mouse ß-defensin-14 from osteoblasts via the p38 MAPK and NF-κB pathways.

Mammalian ß-defensins are small cationic peptides of approximately 2-6 kDa that have been implicated in mediating innate immune defenses against microbial infection. Previous studies have reported that mouse ß-defensin-14 (MBD­14), based on structural and functional similarities, appears to be an ortholog of human ß-defensin-3 (HBD-3). The aim of this study was to identify the signaling pathways that contribute to the expression of MBD-14 in mouse osteoblasts (OBs) upon contact with methicillin-resistant Staphylococcus aureus (S. aureus) supernatant (SAS) to provide a theoretical basis for the use of MDB-14 as a therapeutic agent in the treatment of intramedullary infection with S. aureus in vivo. The bacterial exoproducts released by S. aureus mainly include a large amount of enterotoxins. Using mouse OBs, the release and regulation of MBD-14 was evaluated by real-time polymerase chain reaction (PCR) and enzyme­linked immunosorbent assay (ELISA) following exposure to SAS. The activation of the p38 mitogen­activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) and nuclear factor-κB (NF-κB) pathways was determined by western blot analysis. OBs treated with lipopolysaccharide (LPS) were used as the positive control. The results revealed that SAS significantly promoted the phosphorylation of p38 MAPK, NF-κB and the inhibitory subunit of NF-κBα (IκBα) in a time-dependent manner. The treatment of OBs with SB203580 (an inhibitor of p38 MAPK) and pyrrolidine dithiocarbamate (PDTC, an inhibitor of NF-κB) prior to stimulation with SAS significantly inhibited the phosphorylation and mRNA expression of p38 MAPK and NF-κB p65, simultaneously reducing the release of MBD-14. Our findings suggest that the release of MBD-14 is mediated at least in part through the activation of p38 MAPK and NF-κB in response to S. aureus­secreted bacterial exoproducts. Moreover, our data demonstrate the innate immune capacity of OBs under conditions of bacterial challenge to enhance the local expression of this MBD-14, a peptide with anti­staphylococcal activity.

Ultrasonically enhanced rifampin activity against internalized Staphylococcus aureus.

Staphylococcus aureus (S. aureus) is the principle causative agent of osteomyelitis, accounting for 80% of all human cases. S. aureus internalized in osteoblasts escapes immune response, including engulfment by phagocytes. It also escapes the action of a number of antibiotics. Ultrasound increases cell membrane permeability to a number of drugs. Following an internalization assay, we used low-frequency, low-power ultrasound combined with the antibiotic rifampin to target S. aureus internalized in human osteoblasts. Tryptic soy agar (TSA) was used to quantitate the antibacterial effect of rifampin combined with low-frequency ultrasound. A Cell Counting Kit-8 (CCK-8) assay was used to evaluate cell viability following exposure to ultrasound. Our data revealed that rifampin successfully penetrates into osteoblasts and kills internalized S. aureus in osteoblasts, while low-frequency ultrasound promotes this process. Ultrasound had a negative impact on the cell viability of osteoblasts; however, this damage was slight and reversible. Ultrasound-enhanced antibiotic efficiency to bacteria internalized in the osteoblasts may contribute to the control of chronic infection to reduce recurrence.

Biocompatibility of chitosan-coated iron oxide nanoparticles with osteoblast cells.

BACKGROUND: Bone disorders (including osteoporosis, loosening of a prosthesis, and bone infections) are of great concern to the medical community and are difficult to cure. Therapies are available to treat such diseases, but all have drawbacks and are not specifically targeted to the site of disease. Chitosan is widely used in the biomedical community, including for orthopedic applications. The aim of the present study was to coat chitosan onto iron oxide nanoparticles and to determine its effect on the proliferation and differentiation of osteoblasts. METHODS: Nanoparticles were characterized using transmission electron microscopy, dynamic light scattering, x-ray diffraction, zeta potential, and vibrating sample magnetometry. Uptake of nanoparticles by osteoblasts was studied by transmission electron microscopy and Prussian blue staining. Viability and proliferation of osteoblasts were measured in the presence of uncoated iron oxide magnetic nanoparticles or those coated with chitosan. Lactate dehydrogenase, alkaline phosphatase, total protein synthesis, and extracellular calcium deposition was studied in the presence of the nanoparticles. RESULTS: Chitosan-coated iron oxide nanoparticles enhanced osteoblast proliferation, decreased cell membrane damage, and promoted cell differentiation, as indicated by an increase in alkaline phosphatase and extracellular calcium deposition. Chitosan-coated iron oxide nanoparticles showed good compatibility with osteoblasts. CONCLUSION: Further research is necessary to optimize magnetic nanoparticles for the treatment of bone disease.

[Effect of dopamine and norepinephrine on hemodynamics and tissue oxygenation of patients with septic shock].

OBJECTIVE: To evaluate the effects of dopamine (DA) and norepinephrine (NE) on hemodynamics and tissue oxygenation of patients with septic shock. METHODS: Sixteen patients with septic shock were assigned to the groups of DA and NE randomly. They were given DA or NE for 4 hours, then shifted to NE or DA. Heart rate (HR), mean artery pressure (MAP), cardiac index (CI), stroke index (SI), systemic vascular resistance index (SVRI), acceleration index (ACI), left cardiac work index (LCWI), thoracic fluid content (TFC), mixed venous oxygen saturation (SvO2), venous lactate concentration (Lac), and urine volume per hour (UV) were measured at the end of the 1st, 2nd, 3rd, and 4th hour of the treatment for each of the two drugs. Creatinine clearance rate (CCr) was measured at the end of the 4th hour of study. The differences of all parameters were compared between the two groups. RESULTS: (1)There were no differences in MAP, SI and TFC between the two groups (P>0.05), and there was significant difference in LCWI between the two groups at the end of the 2nd hour (P=0.031). HR, CI and ACI were higher while SVRI was lower in DA group than that in NE group, with significant differences between the two groups (P<0.05 or P<0.01). The results suggested that both DA and NE had good effect on raising blood pressure; DA was more effective than NE in increasing oxygen delivery (DO2), but its use was confined to certain extent due to its effect of accelerating HR. (2) There were no significant differences of SvO2 between the two groups (P>0.05),and the levels of Lac in the group of DA were significantly higher than those in the group of NE (all P<0.05). The results suggested that NE was better than DA in improving internal organ perfusion and tissue oxygenation. (3)UV in the group of DA was significantly higher than that in the group of NE at different time points (P<0.05 or P<0.01). CCr at the end of the 4th hour in DA group was significant higher than that in NE group (P=0.023). The results suggested that DA had significant effects in increasing urine and CCr, denoting that it might have an effect in protecting renal function. CONCLUSION: DA has better effect of increasing DO2 than NE, but its side effect of accelerating HR may to some degree restrict its use. NE may has better effects than DA on enhancing visceral perfusion and tissue oxygenation. DA may be a better choice for patients with septic shock accompanied by oliguria and/or renal dysfunction. NE may be a better choice for the patients of septic shock with tachycardia and/or severe tissue hypoxia.

[Secreted expression of the combinant antimicrobial peptide PL in Pichia pastoris and its antibacterial activity in vitro].

In order to obtain a high activity antibacterial peptide, An expression vector pPICZalphaA-pl is constructed with a tandem of four antimicrobial peptides in the same direction,which includes Protegrin-1 (PG-1), Scorpion Defensin (SD), Metalnikowin-2A and Sheep Myeloid Antibacterial Peptide (SMAP-29) (serial number in GenBank are AAB27599, AAAB27538, P80409 and P49928 respectively). At the same time the expression vector pPICZalphaA-sd which express Scorpion Defensin was contructed. The expression vectors of pPICZalphaA-pl and pPICZalphaA-sd were linearized and transformed into the yeast host strain X-33 respectively. Under the control of the promoter AOX1 (alcohol oxidase1), the peptides PL and SD were secreted expressed. Their heat-stable property, acid-stable property and MIC were detected in vitro. The results suggest the peptides PL and SD have good heat-stable and acid-stable properties, and the combinant PL peptide showes higher antibacterial activity against several Gram-positive bacteria (G+) and Gram-negative bacteria (G-) than the peptide SD, especially against Escherichia coli. The antibacterial activity of combinant antimicrobial peptide PL shows its far exploiting perspective.