Factors affecting the intraoperative calculi excretion during flexible ureteroscopy lithotripsy: an in vitro analysis.

OBJECTIVE: To explore the parameters influencing intraoperative calculi excretion (ICE) during flexible ureteroscopy lithotripsy (fURL) using in vitro simulation experiments. METHODS: 3D-printed human kidney models were used to simulate the elimination of gravel during fURL. The factors influencing the ICE during fURL were analyzed by comparing the effects of different degrees of hydronephrosis (mild, moderate, and severe), surgical positions (supine and lateral position), ratios of endoscope-sheath diameter (RESD) (0.625, 0.725, and 0.825), gravel sizes (0.50-1.00 mm, 0.25-0.50 mm, and 0.10-0.25 mm), and ureteral access sheaths (UASs) (traditional UAS and negative-pressure UAS) on ICE. RESULTS: The impacts of various UAS, RESD, degree of hydronephrosis, surgical positions, and gravel sizes on ICE were all significant (p < 0.05). We found no evidence of multicollinearity for all the independent variables, and the linear regression equation fitted as ICE ( g / min ) = 0.102 + 0.083 ∗ UAS grade - 0.050 ∗ RESD grade - 0.048 ∗ hydronephrosis grade + 0.065 ∗ position grade - 0.027 ∗ gravel size grade (R2 = 0.569). CONCLUSION: Employing negative-pressure UAS, smaller RESD, milder hydronephrosis, lateral position, and smaller gravel size contribute to improved ICE during fURL. Among them, the adoption of negative-pressure UAS had the most substantial effects.

The optimal ratio of endoscope-sheath diameter with negative-pressure ureteral access sheath: an in vitro research.

PURPOSE: To maintain safe intrarenal pelvic pressure (IPP), the combination of flexible ureteroscope (fURS) and traditional ureteral access sheath (T-UAS) should maintain a basic rule that is the ratio of endoscope-sheath diameter (RESD) ≤ 0.75. However, the negative-pressure ureteral access sheath (NP-UAS) may break the rule of negative pressure suction. This study aimed to examine the effect of NP-UAS on IPP and flow rate (FR) with varying RESD. METHODS: In a 3D-printed renal model, flexible ureteroscopy lithotripsy (fURL) was replicated. Six sizes of fURS paired with 12Fr T-UAS and NP-UAS resulted in six distinct RESDs of 0.63, 0.78, 0.87, 0.89, 0.90, and 0.91. While the irrigation pressure (IRP) was set between 100 and 800 cmH2O and the sucking pressure (SP) was set between 0 and 800 cmH2O, the IPP and FR were measured in each RESD. RESULTS: NP-UASs can reduce the IPP and increase the FR at the same RESD compared to T-UASs. The IPP decreased with increasing SP with NP-UAS. When RESD ≤ 0.78, T-UAS and NP-UAS can maintain IPP < 40 cmH2O in most circumstances. When RESD = 0.87, it is challenging for T-UAS to sustain IPP < 40 cmH2O; however, NP-UAS can do so. When RESD ≥ 0.89, it is difficult to maintain an IPP < 40 cmH2O even with NP-UAS. CONCLUSION: NP-UAS can decrease IPP and increase FR compared with T-UAS. To maintain a safe IPP, it is recommended that RESD < 0.85 when utilizing NP-UAS.

Workplace violence against Chinese licensed doctors: a cross-sectional study.

Introduction: China has issued and implemented a series of policies aimed at preventing and controlling workplace violence (WPV) against licensed doctors. However, the prevalence of WPV has not been fundamentally curbed. The aim of this study was to present the prevalence of WPV, identify its influencing factors and propose responsive measures. Method: The online Chinese Physician Practice Survey was conducted with purposive sampling method among licensed doctors in China from January 2022 to June 2022. Data covered licensed doctors' sociodemographic characteristics, occupational characteristics, prevalence of WPV, and perception of effective countermeasures. Results: A total of 74,305 licensed doctors participated in this study. A total of 44.88% of respondents had experienced WPV, among them, either physical violence only (1.06%) or non-physical violence only (89.91%) or encountered both of them (9.03%). Age, gender, marital status, education level, professional title and registration type were all associated with WPV, being younger, non-married, more educated, and higher professional title are all risk factors for WPV. Male (OR = 1.396, 95CI%: 1.355 to 1.439), clinicians (OR = 1.342,95%CI: 1.177 to 1.529), who were single (OR = 1.174, 95%CI: 1.111 to 1.241), with master's degree (OR = 2.021, 95%CI: 1.739 to 2.349) and professional title were subsenior (OR = 1.194, 95%CI: 1.125 to 1.267) were most likely to occur WPV. WPV occurred mostly in provincial capitals, public hospitals, primary and community hospitals, and departments of internal medicine, surgery, pediatrics, emergency medicine and mental health. Overall, 44.24% of doctors perceived that strengthening crackdowns on criminal behaviors was the most effective measure to prevent WPV against healthcare staff. Conclusion: The frequency of WPV decreased after the implementation of relevant laws and policies. Future efforts should be made to strengthen crackdowns on illegal and criminal activities and to issue specific legal provisions on the prevention and control of WPV against doctors.

Electroacupuncture pretreatment alleviates spasticity after stroke in rats by inducing the NF-κB/NLRP3 signaling pathway and the gut-brain axis.

OBJECTIVE: Spasticity is one of the most prevalent ischemic stroke sequelae and the leading cause of disability after stroke. Although electroacupuncture pretreatment has been shown to be effective in the treatment of ischemic stroke, its therapeutic effect and mechanism on post-stroke spasm remain unknown. The purpose of this study was to look into the potential mechanism of electroacupuncture pretreatment in inducing the NF-κB/NLRP3 signaling pathway and the gut-brain axis in the therapy of spasm after stroke. METHODS: After electroacupuncture treatment at Baihui (DU20) and Qubin (G87), the rat model of middle cerebral artery occlusion (MCAO) was first established. HE, Nissl, and TUNEL staining were used to detect pathological alterations in the rat brain. The relative levels of IL-4, IL-6, TNF-α, and TMAO were determined by ELISA. qRT-PCR and Western blot were used to evaluate the mRNA and protein levels of NF-κB p65, NLRP3, caspase3 and caspase9. Gas chromatography-mass spectrometry (GC-MS) was used to determine the levels of short-chain fatty acids (SCFAs) in rat gut. RESULTS: Hippocampal cells from rats with spasticity following stroke in the MCAO group were chaotic and loosely distributed with an unclear border, a blurred nucleolus, and vanished cytoplasm when compared to those from the sham operation group. Furthermore, the number of surviving neurons decreased while the number of apoptotic cells increased. In the I/R group, relative levels of IL-6, TNF-α, and TMAO increased considerably, while NF-κB p65, NLRP3, caspase3, and caspase9 were dramatically downregulated. The intestinal contents of n-propyl acetate and propyl butyrate were lowered in rats with spasticity following stroke. Electroacupuncture treatments miraculously remedied all of the foregoing pathogenic alterations. CONCLUSION: Pretreatment with electroacupuncture relieves spasticity after stroke by decreasing the inflammatory response, suppressing the NF-κB/NLRP3 signaling pathway, and modulating the gut-brain axis by increasing n-propyl acetate and propyl butyrate levels in the bowel. Our findings establish a new molecular mechanism and theoretical foundation for electroacupuncture therapy of ischemic stroke.

Pre-operative nasal probe tests with adrenaline and lidocaine ease insertion during flexible bronchoscopy and reduce post-operative bleeding: a randomized controlled trial.

BACKGROUND: Nasal insertion is the preferred method for non-intubated patients in flexible bronchoscopy; however, the relatively narrow nasal cavity results in difficulties related to bronchoscope insertion. This study aimed to investigate whether pre-operative nasal probe tests could reduce the time to pass the glottis, improve the first-pass success rate and patients' tolerance, and reduce postoperative bleeding. METHODS: This three-arm prospective randomized controlled trial was conducted in a tertiary hospital between May and October 2020. Three hundred patients requiring diagnosis and treatment using flexible bronchoscopy were randomly allocated to three groups: control group, simple cotton bud detection group (CD group), and adrenaline + lidocaine detection group (AD group). The primary outcome was the time to pass the glottis. Secondary outcomes included the first-pass success rate, the patients' tolerance scores, and post-operative bleeding. One-way analysis of variance, Kruskal-Wallis H test, Chi-squared test, Fisher's exact test, and Bonferroni's multiple comparison tests were used in this study. RESULTS: In total, 189 men and 111 women were enrolled in this study, with a mean age of 55.72 ± 12.86 years. The insertion time was significantly shorter in the AD group than in the control group (18.00 s [12.00-26.50 s] vs . 24.00 s [14.50-45.50 s], P = 0.005). Both the AD (99% vs . 83%, χ2 = 15.62, P < 0.001) and CD groups (94% vs . 83%, χ2 = 5.94, P = 0.015) had a significantly higher first-pass success rate than the control group. Compared with the control group, post-operative bleeding (1% vs . 13%, χ2 = 11.06, P < 0.001) was significantly lower in the AD group. However, no significant difference was found in the patients' tolerance scores. CONCLUSIONS: Pre-operative nasal cavity probe tests especially with adrenaline and lidocaine during flexible bronchoscopy can significantly reduce the time to pass the glottis, improve the first-pass success rate, and reduce post-operative nasal bleeding. Pre-operative nasal probe tests are recommended as a time-saving procedure for patients undergoing flexible bronchoscopy. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR), ChiCTR2000032668; http://www.chictr.org.cn/showprojen.aspx?proj=53321 .

All-in-one approaches for triple-negative breast cancer therapy: metal-phenolic nanoplatform for MR imaging-guided combinational therapy.

BACKGROUND: Conventional chemotherapy has poor efficacy in triple-negative breast cancer (TNBC) which is highly heterogeneous and aggressive. Imaging-guided therapy is usually combined with diverse treatment modalities, could realize the integration of diagnosis and treatments. Therefore, the primary challenge for combinational therapy is designing proper delivery systems to accomplish multiple synergistic effects. RESULTS: Herein, a facile nanoplatform was manufactured to fulfill the all-in-one approaches for TNBC combinational therapy. Fe3+-based metal-phenolic networks (MPNs) with bovine serum albumin (BSA) modification served as drug delivery carriers to encapsulate bleomycin (BLM), forming BFE@BSA NPs. The self-assembly mechanism, pH-responsive drug release behavior, and other physicochemical properties of this system were characterized. The potential of BFE@BSA NPs as photothermal transduction agents and magnetic resonance imaging (MRI) contrast agents was explored. The synergistic anti-tumor effects consisting of BLM-induced chemotherapy, Fenton reactions-mediated chemodynamic therapy, and photothermal therapy-induced apoptosis were studied both in vitro and in vivo. Once internalized into tumor cells, released BLM could cause DNA damage, while Fenton reactions were initiated to produce highly toxic •OH. Upon laser irradiation, BFE@BSA NPs could convert light into heat to achieve synergistic effects. After intravenous administration, BFE@BSA NPs exhibited great therapeutic effects in 4T1 tumor xenograft model. Moreover, as T1-weighted MRI contrast agents, BFE@BSA NPs could provide diagnosis and treatment monitoring for individualized precise therapy. CONCLUSIONS: A nano-system that integrated imaging and combinational therapy (chemotherapy, chemodynamic therapy and photothermal therapy) were developed to kill the tumor and monitor therapeutic efficacy. This strategy provided an all-in-one theranostic nanoplatform for MRI-guided combinational therapy against TNBC.

Nebulized Ipratropium bromide protects against tracheal and bronchial secretion during bronchoscopy: A randomized controlled trial.

BACKGROUND: Anticholinergic administration prior to flexible bronchoscopy has been investigated, but studies have not yielded consistent results. METHODS: Patients were randomized 1:1 to receive nebulized 4 ml ipratropium bromide (1 mg, n = 125) or placebo (n = 125) for 15 minutes as premedication, 20 to 40 minutes before bronchoscopy. Airway secretions, bleeding, patient discomfort, procedure time, and procedure-related adverse events were compared between the groups. RESULTS: Nebulized ipratropium bromide prior to bronchoscopy could reduce airway secretions and patient discomfort (P = .02; P < .001, respectively), but not tracheobronchial bleeding or procedure time (P = .51, P = .36, respectively). Chest nodule or mass was the most common indication for performing bronchoscopy. The adverse events were higher in ipratropium bromide group, and hypertension was the most common complication. CONCLUSION: Nebulized ipratropium bromide prior to bronchoscopy is a more effective regimen that shows a practical benefit on the airway secretions and patient comfort, though these effects may not translate into any marked reduction in bleeding or of procedure time under general anesthesia. We suggest that routine nebulized ipratropium bromide premedication for bronchoscopy could be useful and beneficial. TRIAL REGISTRATION: chictr.org.cn: ChiCTR1800016881.

Facile preparation of recombinant spider eggcase silk spheres via an HFIP-on-Oil approach.

Versatile spider silk proteins have been prepared by various methods in morphology of spheres for functional applications. Inspired from natural spinning process, a facile approach for the fabrication of silk spheres is described. Distinct from the traditional emulsification method, silk spheres were assembled as rapidly as 10 s by using the HFIP-on-Oil method without any surfactants and agitation used. Notably, a series of factors, such as evaporation rate of HFIP, polarity and molecular weight of oils play central roles on the final silk morphologies. With regard to the increase of protein concentrations, the average dimension and size distribution of silk spheres were both increased. Together with present study, silk spheres prepared by other methods were summarized for comparison in drug delivery applications. As a proof-of-concept, silk spheres loaded with Rhodamine B and Doxorubicin were investigated for the potential proteinase-enhanced drug delivery. On the extracellular environment, ethanol-mediated silk spheres exhibited higher resistance against enzymatic degradation of proteinase K when compared with pristine spheres. Under fluorescent detection by the aid of CLSM, proteinase-enhanced release behaviors were further demonstrated through in-vitro experiments within Hela cells. The facile fabrication of spheres with tunable ß-sheets establishes a fascinating platform for functional silk-based applications.

One-Step in Situ Detection of miRNA-21 Expression in Single Cancer Cells Based on Biofunctionalized MoS2 Nanosheets.

Here, we report the one-step in situ detection of targeted miRNAs expression in single living cancer cells via MoS2 nanosheet-based fluorescence on/off probes. The strategy is based on the folic acid (FA)-poly(ethylene glycol)-functionalized MoS2 nanosheets with adsorbed dye-labeled single-stranded DNA (ssDNA). Once the nanoprobes are internalized into cancer cells, the hybridization between the probes and target miRNA results in the detachment of dye-labeled ssDNA from MoS2 nanosheets surface, leading to the green fluorescence recovery. In this nanoprobe, MoS2 nanosheets offer advantages of high fluorescence quenching efficiency and extremely low toxicity. The FA conjugation could protect the probes and improve cancer cell transfection efficiency. The ability of this nanoprobe for endogenous miRNA detection in single living cancer cells is demonstrated for two types of cancer cells with different miRNA-21 expressions (MCF-7 and Hela cells). This functionalized MoS2 nanosheet-based nanoprobes could provide a sensitive and real-time detection of intracellular miRNA detection platform.

Malat1 activates autophagy and promotes cell proliferation by sponging miR-101 and upregulating STMN1, RAB5A and ATG4D expression in glioma.

The long noncoding RNA Malat1 has been reported to be an oncogene that promotes tumor progress and correlates with prognosis in glioma. Growing evidence shows that autophagy plays a very important role in tumorigenesis and tumor cell survival, but whether Malat1 regulates autophagy in glioma is still unclear. In this study, we found that Malat1 expression and autophagy activity were significantly increased in glioma tissues compared with adjacent normal tissues. Additionally, Malat1 level was positively correlated with the expression of LC3-II (autophagy marker) mRNA in vivo. In vitro assays revealed that Malat1 significantly promoted autophagy activation and cell proliferation in glioma cells. More importantly, inhibition of autophagy by 3-MA relieved Malat1-induced cell proliferation. These data demonstrated that Malat1 activates autophagy and increases cell proliferation in glioma. We further investigated the molecular mechanisms whereby Malat1 functioned on glioma cell autophagy and proliferation. We found that Malat1 served as an endogenous sponge to reduce miR-101 expression by directly binding to miR-101. Moreover, Malat1 abolished the suppression effects of miR-101 on glioma cell autophagy and proliferation, which involved in upregulating the expression of miR-101 targets STMN1, RAB5A and ATG4D. Overall, our study elucidated a novel Malat1-miR-101-STMN1/RAB5A/ATG4D regulatory network that Malat1 activates autophagy and promotes cell proliferation by sponging miR-101 and upregulating STMN1, RAB5A and ATG4D expression in glioma cells.

[The Diagnostic Value of Endobronchial Ultrasound-guided Needle Aspiration Biopsy for Lung or Mediastinal Lymph Node Cancer and Tuberculosis].

OBJECTIVES: To determine the value of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in diagnosing lung or mediastinal lymph node cancer and tuberculosis. METHODS: Clinical and pathological data of 553 patients who underwent EBUS-TBNA from January 2013 to September 2016 in West China Hospital of Sichuan University were reviewed. The sensitivity, specificity and accuracy of EBUS-TBNA for diagnosing lymph node tumor and tuberculosis of hilar and mediastinal lymph nodes were calculated. RESULTS: The sensitivity, specificity and accuracy of EBUS-TBNA in diagnosing hilar and mediastinal lymph node cancer were 89.2% (263/295), 100% (247/247) and 94.1% (510/542), respectively, compared with 70% (76/117), 97.2% (385/396) and 89.9% (461/513), respectively, for diagnosing tuberculosis identified though granulomatous biopsy. In the 102 cases with acid fast staining and TB-PCR, 63.7% accuracy (58/91), 90.9% (10/11) sensitivity and 66.7% (68/102) specificity were found for any positive findings from acid fast bacilli or TB-DNA. CONCLUSIONS: EBUS-TBNA has high sensitivity and specificity for diagnosing hilar and mediastinal tumor, which can be used in combination with acid fast staining and TB-PCR for diagnosing tuberculosis.

A fluorescence turn-on biosensor based on graphene quantum dots (GQDs) and molybdenum disulfide (MoS2) nanosheets for epithelial cell adhesion molecule (EpCAM) detection.

This paper presents a "turn-on" fluorescence biosensor based on graphene quantum dots (GQDs) and molybdenum disulfide (MoS2) nanosheets for rapid and sensitive detection of epithelial cell adhesion molecule (EpCAM). PEGylated GQDs were used as donor molecules, which could not only largely increase emission intensity but also prevent non-specific adsorption of PEGylated GQD on MoS2 surface. The sensing platform was realized by adsorption of PEGylated GQD labelled EpCAM aptamer onto MoS2 surface via van der Waals force. The fluorescence signal of GQD was then quenched by MoS2 nanosheets via fluorescence resonance energy transfer (FRET) mechanism. In the presence of EpCAM protein, the stronger specific affinity interaction between aptamer and EpCAM protein could detach GQD labelled EpCAM aptamer from MoS2 nanosheets, leading to the restoration of fluorescence intensity. By monitoring the change of fluorescence signal, the target EpCAM protein could be detected sensitively and selectively with a linear detection range from 3nM to 54nM and limit of detection (LOD) around 450pM. In addition, this nanobiosensor has been successfully used for EpCAM-expressed breast cancer MCF-7 cell detection.

A graphene quantum dot@Fe3O4@SiO2 based nanoprobe for drug delivery sensing and dual-modal fluorescence and MRI imaging in cancer cells.

A novel graphene quantum dot (GQD)@Fe3O4@SiO2 based nanoprobe was reported for targeted drug delivery, sensing, dual-modal imaging and therapy. Carboxyl-terminated GQD (C-GQD) was firstly conjugated with Fe3O4@SiO2 and then functionalized with cancer targeting molecule folic acid (FA). DOX drug molecules were then loaded on GQD surface of Fe3O4@SiO2@GQD-FA nanoprobe via pi-pi stacking, which resulted in Fe3O4@SiO2@GQD-FA/DOX conjugates based on a FRET mechanism with GQD as donor molecules and DOX as acceptor molecules. Meanwhile, we successfully performed in vitro MRI and fluorescence imaging of living Hela cells and monitored intracellular drug release process using this Fe3O4@SiO2@GQD-FA/DOX nanoprobe. Cell viability study demonstrated the low cytotoxicity of Fe3O4@SiO2@GQD-FA nanocarrier and the enhanced therapeutic efficacy of Fe3O4@SiO2@GQD-FA/DOX nanoprobe for cancer cells. This luminomagnetic nanoprobe will be a potential platform for cancer accurate diagnosis and therapy.

Liquid-Based Cytology Preparation Can Improve Cytological Assessment of Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration.

OBJECTIVE: This study investigated whether liquid-based cytology (LBC) can improve diagnostic values of cytological assessment of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). STUDY DESIGN: A cohort of 600 cases in West China Hospital was prospectively studied from June 2012 to September 2013. EBUS-TBNA was carried out in outpatients under local anesthesia and moderate sedation. The procedure was performed with an echobronchoscope (BF-UC160F-OL8, Olympus, Tokyo, Japan). Histological cores were stained with hematoxylin and eosin for further study. Additional immunohistological analysis was performed for establishing a reliable diagnosis when necessary. Aspirates were smeared on glass slides and separate aspirates were processed by the monolayer SurePath method. RESULTS: In total, 480 malignant tumors and 120 benign lesions were confirmed by histological examination. The sensitivity of SurePath liquid-based preparations and conventional smears was 82.1 and 56%, and the specificity was 87.5 and 82.5%, respectively. The combined specificity was 100%. Positive predictive values of the two groups were 96.3 and 92.8%, whereas negative predictive values were 54.9 and 31.9%, respectively. The difference between the two groups was significant (p < 0.001). CONCLUSIONS: LBC preparation can improve cytological assessment of EBUS-TBNA. Histological study is necessary in cases in which the cytological diagnosis is obscure.

A graphene oxide based fluorescence resonance energy transfer (FRET) biosensor for ultrasensitive detection of botulinum neurotoxin A (BoNT/A) enzymatic activity.

Botulinum neurotoxins (BoNTs) are among the most potent toxic bacterial proteins for humans, which make them potential agents for bioterrorism. Therefore, an ultrasensitive detection of BoNTs and their active states is in great need as field-deployable systems for anti-terrorism applications. We report the construction of a novel graphene oxide (GO)-peptide based fluorescence resonance energy transfer (FRET) biosensor for ultrasensitive detection of the BoNT serotype A light chain (BoNT-LcA) protease activity. A green fluorescence protein (GFP) modified SNAP-25 peptide substrate (SNAP-25-GFP) was optimally designed and synthesized with the centralized recognition/cleavage sites. This FRET platform was constructed by covalent immobilization of peptide substrate on GO with BSA passivation which have advantages of low non-specific adsorption and high stability in protein abundant solution. BoNT-LcA can specifically cleave SNAP-25-GFP substrate covalently immobilized on GO to release the fragment with GFP. Based on fluorescence signal recovery measurement, the target BoNT-LcA was detected sensitively and selectively with the linear detection range from 1fg/mL to 1pg/mL. The limit of detection (LOD) for BoNT-LcA is around 1fg/mL.

Effects of human parvovirus B19 VP1 unique region protein on macrophage responses.

BACKGROUND: Activity of secreted phospholipase A (sPLA2) has been implicated in a wide range of cellular responses. However, little is known about the function of human parvovirus B19-VP1 unique region (VP1u) with sPLA2 activity on macrophage. METHODS: To investigate the roles of B19-VP1u in response to macrophage, phospholipase A2 activity, cell migration assay, phagocytosis activity, metalloproteinase assay, RT-PCR and immunoblotting were performed. RESULTS: In the present study, we report that migration, phagocytosis, IL-6, IL-1beta mRNA, and MMP9 activity are significantly increased in RAW264.7 cells by B19-VP1u protein with sPLA2 activity, but not by B19-VP1uD175A protein that is mutated and lacks sPLA2 activity. Additionally, significant increases of phosphorylated ERK1/2 and JNK proteins were detected in macrophages that were treated with B19-VP1u protein, but not when they were treated with B19-VP1uD175A protein. CONCLUSION: Taken together, our experimental results suggest that B19-VP1u with sPLA2 activity affects production of IL-6, IL-1beta mRNA, and MMP9 activity, possibly through the involvement of ERK1/2 and JNK signaling pathways. These findings could provide clues in understanding the role of B19-VP1u and its sPLA2 enzymatic activity in B19 infection and B19-related diseases.

Up-regulation of adhesion molecule expression and induction of TNF-alpha on vascular endothelial cells by antibody against human parvovirus B19 VP1 unique region protein.

BACKGROUND: Human parvovirus B19 infection has been frequently described as a cause or trigger of various autoimmune diseases. In previous studies, we have postulated the association among human parvovirus B19 (B19)-VP1 unique region (VP1u), production of anti-beta2-glycoprotein I (anti-beta2GPI) antibody and anti-phospholipid syndrome (APS)-like autoimmunity. However, the precise role of B19-VP1u in induction of APS is still obscure. METHODS: To further elucidate the pathogenic roles of VP1u in B19 infection and autoimmunity, we examined the effect of anti-B19-VP1u IgG antibodies on endothelial cells that is recognized to play crucial roles in APS. Human vascular endothelial cells, ECV-304, were incubated with various preparations of purified human or rabbit IgG. The activation of endothelial cells and production of cytokines were assessed by flow cytometry and ELISA, respectively. RESULTS: Purified IgG from rabbits immunized with recombinant B19-VP1u proteins can up-regulate ICAM-1 (CD54), VCAM-1 (CD106), E-selectin (CD62E), MHC class II (HLA-DR, DP, DQ) molecule expression, and TNF-alpha production in endothelial cells as compared to those endothelial cells cultured with control IgG. Additionally, significantly increased phosphorylated-P38 mitogen-activated protein kinase (P38 MAPK) and iNOS were observed in both human anti-beta2GPI IgG and rabbit anti-B19-VP1u IgG treated-ECV-304 cells, respectively. CONCLUSIONS: These experimental results imply that antibodies against B19-VP1u play important roles in the immunopathological processes as well as human anti-beta2GPI IgG that leads to development of APS by involving p38 phosphorylation and iNOS activation. It could provide a clue in understanding the role of anti-B19-VP1u antibodies in APS manifestations.