Exosomes derived from vMIP-II-Lamp2b gene-modified M2 cells provide neuroprotection by targeting the injured spinal cord, inhibiting chemokine signals and modulating microglia/macrophage polarization in mice.

Inflammation is one of the key injury factors for spinal cord injury (SCI). Exosomes (Exos) derived from M2 macrophages have been shown to inhibit inflammation and be beneficial in SCI animal models. However, lacking targetability restricts their application prospects. Considering that chemokine receptors increase dramatically after SCI, viral macrophage inflammatory protein II (vMIP-II) is a broad-spectrum chemokine receptor binding peptide, and lysosomal associated membrane protein 2b (Lamp2b) is the key membrane component of Exos, we speculated that vMIP-II-Lamp2b gene-modified M2 macrophage-derived Exos (vMIP-II-Lamp2b-M2-Exo) not only have anti-inflammatory properties, but also can target the injured area by vMIP-II. In this study, using a murine contusive SCI model, we revealed that vMIP-II-Lamp2b-M2-Exo could target the chemokine receptors which highly expressed in the injured spinal cords, inhibit some key chemokine receptor signaling pathways (such as MAPK and Akt), further inhibit proinflammatory factors (such as IL-1ß, IL-6, IL-17, IL-18, TNF-α, and iNOS), and promote anti-inflammatory factors (such as IL-4 and Arg1) productions, and the transformation of microglia/macrophages from M1 into M2. Moreover, the improved histological and functional recoveries were also found. Collectively, our results suggest that vMIP-II-Lamp2b-M2-Exo may provide neuroprotection by targeting the injured spinal cord, inhibiting some chemokine signals, reducing proinflammatory factor production and modulating microglia/macrophage polarization.

Development and validation of a machine learning model for differential diagnosis of malignant pleural effusion using routine laboratory data.

BACKGROUND: The differential diagnosis of malignant pleural effusion (MPE) and benign pleural effusion (BPE) presents a clinical challenge. In recent years, the use of artificial intelligence (AI) machine learning models for disease diagnosis has increased. OBJECTIVE: This study aimed to develop and validate a diagnostic model for early differentiation between MPE and BPE based on routine laboratory data. DESIGN: This was a retrospective observational cohort study. METHODS: A total of 2352 newly diagnosed patients with pleural effusion (PE), between January 2008 and March 2021, were eventually enrolled. Among them, 1435, 466, and 451 participants were randomly assigned to the training, validation, and testing cohorts in a ratio of 3:1:1. Clinical parameters, including age, sex, and laboratory parameters of PE patients, were abstracted for analysis. Based on 81 candidate laboratory variables, five machine learning models, namely extreme gradient boosting (XGBoost) model, logistic regression (LR) model, random forest (RF) model, support vector machine (SVM) model, and multilayer perceptron (MLP) model were developed. Their respective diagnostic performances for MPE were evaluated by receiver operating characteristic (ROC) curves. RESULTS: Among the five models, the XGBoost model exhibited the best diagnostic performance for MPE (area under the curve (AUC): 0.903, 0.918, and 0.886 in the training, validation, and testing cohorts, respectively). Additionally, the XGBoost model outperformed carcinoembryonic antigen (CEA) levels in pleural fluid (PF), serum, and the PF/serum ratio (AUC: 0.726, 0.699, and 0.692 in the training cohort; 0.763, 0.695, and 0.731 in the validation cohort; and 0.722, 0.729, and 0.693 in the testing cohort, respectively). Furthermore, compared with CEA, the XGBoost model demonstrated greater diagnostic power and sensitivity in diagnosing lung cancer-induced MPE. CONCLUSION: The development of a machine learning model utilizing routine laboratory biomarkers significantly enhances the diagnostic capability for distinguishing between MPE and BPE. The XGBoost model emerges as a valuable tool for the diagnosis of MPE.

Localized Surface Plasmon Resonance Sensor Based at Metallic Sphere Dimer Particle.

Simulated transmission spectrums of the sphere dimer nanoparticle and the nanoshell structure by the Finite-Difference time-Domain method are present. The considered structure is silver or SiO2 dimer nanoparticle and nanoshell structures, and the particle distance is 10 nm. There is little transmission dip in the transmission spectrums for the silver dimer nanoparticle and nanoshell structure in the visible wavelength range, which arisen from the excitation of the Localized Surface Plasmon Resonance. The transmission dip sensitivity with the index refractive for the silver dimer nanoparticle is about 80 nm RIU­1. Meanwhile, the electric field enhancement and localization properties of the Silver dimer nanoparticle is better than that of the SiO2 dimer nanoparticle. Meanwhile, these structures can extensively apply to biochemical sensor devices design and localized field enhancement device so on.

[Cloning, expression and identification of gametocyte specific protein Pfgdv1 of Plasmodium falciparum].

OBJECTIVE: To clone a gametocyte specific protein Pfgdv1 of Plasmodium falciparum, express and identify recombinant Pfgdvl protein in vitro. METHODS: PCR was performed to amplify Pfgdv1 from P. falciparum DNA which was got from the patient who was infected with P. falciparum, and the PCR product was inserted into pET28a (+) vector. pET28a-Pfgdv1 recombinant plasmid was constructed and transformed into E. coli host BL21 (DE3+). IPTG was used to induce the recombinant Pfgdv1 protein fused with His tag, and the protein was purified by His-NTA affinity chromatography. The recombinant protein was identified by SDS-PAGE and Western blotting. RESULTS: The PCR product of Pfgdv1 gene was about 1.65 kb, meeting the expectation of predicted fragment size. The recombinant protein was about 67 kDa, which could be recognized by His-Tag monoclonal antibody. CONCLUSION: The Pfgdv1 gene of P. falciparum is successfully cloned, and the recombinant Pfgdv1 protein is expressed, thereby providing an opportunity for further study on transmission blocking vaccine.

[In vitro Effect of Hypericin against Toxoplasma gondii Tachyzoites].

Objective: To investigate the killing effect of hypericin on tachyzoites of Toxoplasma gondii RH strain in vitro. Methods: Normal saline （group A） and different concentrations of hypericin (5 µg/ml, group B; 50 µg/ml, group C; 500 µg/ml, group D） were added to T. gondii tachyzoites in 24-well plate（1×10(6)/well）. The tachyzoites were harvested after 2, 4 and 6 h, and underwent the following treatment: trypan blue staining to calculate the dyeing rate, Giemsa staining to observe the morphological and structural alterations of tachyzoites, and transmission electron microscopy to observe the ultrastructure of tachyzoites. In addition, flow cytometry was performed to calculate the survival rate of YFP-carrying Toxoplasma with the same treatment. Results: The trypan blue dyeing rate at 2 h after treatment in groups B, C and D was（11.0±3.6）%, （25.0±6.3）% and（40.0±2.7）% respectively, with a significant difference of group D versus B and C （P<0.01）, and groups C and D versus group A ［（6.0±3.0）%）］. The dyeing rate at 4 h and 6 h in group D was（97.0±2.0）% and （98.0±1.7）%, respectively, both significantly higher than that of groups C ［（30.0±7.2）%, （42.7±5.5）%ï¼½, B ［（20.0±3.0）%, （34.0±6.6）%ï¼½ and A ［（10.0±1.0）%, （19.3±4.9）%］（P<0.01）. Giemsa staining showed gradual end swelling and necrosis of tachyzoites with increased treatment duration and dosage. Transmission electron microscopy showed swelling of worm body, gap between cell membrane and matrix, increase and enlargement of vacuoles inside worm body, disruption of cell membrane, and dissolving of inner structures, with increased treatment duration. Flow cytometry showed significant difference of tachyzoite survival rate at 2, 4 and 6 h after hypericin treatment with that of the control group（P<0.01）. The survival rate of group C at 2 h after hypericin treatment was（7.9±1.9）%, significantly lower than that of groups B ［（38.1±5.5）%ï¼½ and A ［（81.8±6.0）%ï¼½ （P<0.01）. No tachyzoite was found to survive in group D at 2 h and in group C at 4 h. The survival rate of group B at 4 and 6 h after hypericin treatment was（14.3±7.9）% and （1.4±1.8）%, respectively, both significantly lower than that of group A［（73.8±11.3）% and（64.1±14.4）%, respectivelyï¼½ （P<0.01）. Conclusion: Hypericin has a remarkable killing effect on T. gondii tachyzoites, and the efficacy positively correlates with the dose and treatment duration.

Crystal structure of (5'S,8'S)-3-(2,5-di-methyl-phen-yl)-8-meth-oxy-3-nitro-1-aza-spiro-[4.5]decane-2,4-dione.

The title compound, C18H22N2O5, was synthesized by nitrification of its enol precursor. The pyrrolidine ring plane adopts a twisted conformation about the C-C bond linking the spiro centre and the C=O group remote from the N atom. It makes dihedral angles of 71.69 (9) and 88.92 (9)°, respectively, with the benzene ring plane and the plane defined by the four C atoms that form the seat of the of the cyclo-hexane chair. At the spiro centre, the NH group is axial and the C=O group is equatorial with respect to the cyclo-hexane ring. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R 2 (2)(8) loops. The dimers are linked by C-H⋯O inter-actions, generating a three-dimensional network.

Seasonal Variation of Alkaloid Contents and Anti-Inflammatory Activity of Rhizoma coptidis Based on Fingerprints Combined with Chemometrics Methods.

The fingerprints of Rhizoma coptidis (Huanglian) collected in different growing periods were established by high-performance liquid chromatography (HPLC), and the seasonal variations of six alkaloids, namely berberine, palmatine, jateorrhizine, coptisine, epiberberine and columbamine were assessed. In order to highlight the differences of their HPLC fingerprints, three chemometrics methods including Spearman's rank correlation, hierarchical clustering analysis (HCA) and principal component analysis were applied. The anti-inflammatory activity of R. coptidis collected in different developing stages was measured by NO inhibition assay. The relationship between HPLC fingerprints and anti-inflammatory activity named spectrum-effect relationship was investigated by partial least squares regression. The anti-inflammatory activity was positively correlated with the alkaloid contents. Berberine, palmatine, coptisine, jateorrhizine and epiberberine were the main anti-inflammatory components on the basis of the quantitative determination of the six alkaloids and spectrum-effect investigation. The collecting time of R. coptidis impacted the plant's alkaloid contents and its anti-inflammatory activity.

[Construction and identification of recombinant Mycobacterium smegmatis vaccine expressing Cysticercus cellulosae cC1 antigen].

OBJECTIVE: To construct recombinant Mycobacterium smegmatis vaccine expressing Cysticercus cellulosae cC1 antigen. METHODS: The recombinant pET28a-cC1 plasmid was extracted and double digested by Xho I and BamH I restriction enzymes, and shuttle plasmid pMV261 was extracted and double digested by Hind III and BamH I restriction enzymes. Both fragments were modified by Klenow fragment to form blunt end, then the large fragments of cC1 and pMV261 plasmid were purified and ligated by T4 ligase enzyme. The recombinant pMV261-cC1 plasmid was constructed and sequenced. Then the pMV261-cC1 plasmid was transformed into Mycobacterium smegmatis by the electrotransformation method. The recombinant cC1-Mycobacterium smegmatis was induced by heat and identified by the Western blotting method with the sera of cysticercosis patients. In addition, the growth states of the Mycobacterium smegmatis and the recombinant cC1-Mycobacterium smegmatis were compared and the growth curves were drawn. RESULTS: The restriction enzyme and sequencing results showed that the recombinant pMV261-cC1 plasmid was successfully constructed. After heat induction, a 40 kD band was showed by PAGE analysis of cC1-Mycobacterium smegmatis. The Western blotting results showed that the sera of cysticercosis patients could recognize the 40 kDa band, which suggested that cC1 protein was expressed in Mycobacterium smegmatis. Compared with the Mycobacterium smegmatis, the recombi- nant cC1-Mycobacterium smegmatis showed no significant difference in proliferation characteristics. CONCLUSION: The recombinant cC1-Mycobacterium smegmatis vaccine has been successfully constructed.

[Research progress on Plasmodium vivax chloroquine resistance].

Malaria remains a serious public health problem, especially in developing countries. With the deepening of the understanding of vivax malaria, Plasmodium vivax is also attracting more and more attention. An effective drug treatment is the foundation of controlling or even eliminating malaria. In recent years, more and more reports of chloroquine-resistance Plasmodium vivax have been reported. Plasmodium vivax chloroquine resistance has been a focus problem in vivax malaria prevention and treatment. In this paper, the research progress on distribution situation, detection methods and molecular markers of Plasmodium vivax chloroquine resistance is summarized.

Design, synthesis and evaluation of novel tacrine-coumarin hybrids as multifunctional cholinesterase inhibitors against Alzheimer's disease.

A series of tacrine-coumarin hybrids (8a-t) were designed, synthesized and evaluated as multifunctional cholinesterase (ChE) inhibitors against Alzheimer's disease (AD). The screening results showed that most of them exhibited a significant ability to inhibit ChE and self-induced ß-amyloid (Aß) aggregation, and to act as metal chelators. Especially, 8f displayed the greatest ability to inhibit acetylcholinesterase (AChE, IC50 = 0.092 µM) and Aß aggregation (67.8%, 20 µM). It was also a good butyrylcholinesterase inhibitor (BuChE, IC50 = 0.234 µM) and metal chelator. Besides, kinetic and molecular modeling studies indicated that 8f was a mixed-type inhibitor, binding simultaneously to active, peripheral and mid-gorge sites of AChE. These results suggested that 8f might be an excellent multifunctional agent for AD treatment.

Design, synthesis and biological evaluation of novel 7-mercaptocoumarin derivatives as α(1)-adrenoceptor antagonists.

Study on the pharmacophore model of α(1)-adrenoceptor (α(1)-AR) antagonists led to design a series of novel 7-mercaptocoumarin derivatives as α(1)-AR antagonists. All designed compounds have been synthesized and biologically evaluated. The results showed that most of them exhibited strong antagonistic activity. Especially compound 6 showed excellent activity, which was better than that of the reference compound prazosin. Structure-activity relationship studies revealed that small hydrophobic group at the terminal heterocyclic ring and ortho substituents on the phenyl ring of phenylpiperazine moiety were the essential structural factors for α(1)-AR antagonistic activity. The pharmacophore modeling studies further clarified their structural contributions to antagonistic activity and also demonstrated that 7-mercaptocoumarin moiety could be a useful scaffold for design of α(1)-AR antagonists.

[Investigation of the effect of heparin gelatin sponge stickers for traumatic tympanic membrane perforation].

OBJECTIVE: To investigate the efficacy of heparin gelatin sponge stickers in the treatment of traumatic perforation of tympanic membrane. METHODS: Total of 79 cases (83 ears) of traumatic perforation of tympanic membrane were randomly divided into two groups: the test group had 54 patients (58 ears), and the control group had 25 cases (25 ears). The test group received the treatment of heparin gelatin sponge stickers, and the control group received conservative traditional drying method. All the subjects were followed up for 4 weeks, observed and recorded the rate and healing period of traumatic tympanic membrane. RESULTS: In 4-week's follow-up, 56 ears were cured in the test group, with a rate of 96.55%. Fourteen ears were cured in the control group with a rate of 56.00%. The healing rate of test group was significantly higher than that of the control group (χ(2) = 18.79, P < 0.01). The average of healing period was 17.6 days in the test group, and 32.0 days in the control group. There were significant differences in healing period between two groups (t = 6.37, P < 0.01). All the cured tympanic membrane in the test group was morphologically complete. In all followed up patients, there were no allergies and signs of infection, as well as other adverse reaction in the process of healing. CONCLUSION: The heparin gelatin sponge can effectively enhance closure of the traumatic perforation of tympanic membrane and can shorten the healing period of traumatic perforation of tympanic membrane, and the smaller of the perforation, the shorter of healing period.

Circulating microRNA expression is associated with genetic subtype and survival of multiple myeloma.

Circulating microRNAs (miRNAs) have shown potential as non-invasive prognostic biomarkers in cancer. Here, we investigated whether miRNAs present in the plasma of multiple myeloma (MM) patients have prognostic utility. We evaluated global miRNA expression profiles in the plasma of 12 multiple myeloma patients and 8 healthy controls using TaqMan Low-Density Arrays. Six miRNAs (miR-148a, miR-181a, miR-20a, miR-221, miR-625, and miR-99b) that were significantly upregulated in MM were selected and further quantified independently by quantitative reverse transcription PCR in plasma from 28 MM patients and 12 healthy controls. Moreover, within the patient group, the expression levels of miR-99b and miR-221 were associated with chromosomal abnormalities t(4; 14) and del(13q), respectively. High levels of miR-20a and miR-148a were related to shorter relapse-free survival. In summary, we have identified aberrant expression of particular circulating miRNAs that are associated with the genetic subtype and survival of MM. These plasma miRNAs have potential as clinical biomarkers in MM.

Self-assembly of tetrapod-shaped CdS nanostructures into 3D networks by a transverse growth process.

Spontaneous formation of 3D tetrapod-shaped CdS nanostructure networks has been achieved for the first time by vapor diffusion-deposition growth from CdS powders. The growth mechanism of the hexagonal and preferentially oriented CdS tetrapod-shaped nanostructures is a combination of the classic vapor-liquid-solid and vapor-solid processes, and the formation of a 3D network results from the spontaneous growths along the longitudinal and across the axial directions of the primarily formed CdS nanorods. Micro-photoluminescence measurements and near-field scanning optical microscopy investigations show that the synthesized CdS tetrapod networks have an excellent luminescence property and can be used as an optical waveguide cavities in which the guided light can be extremely confined.

Ray trace visualization of negative refraction of light in two-dimensional air-bridged silicon photonic crystal slabs at 1.55 microm.

We demonstrate design, fabrication, and ray trace observation of negative refraction of near-infrared light in a two-dimensional square lattice of air holes etched into an air-bridged silicon slab. Special surface morphologies are designed to reduce the impedance mismatch when light refracts from a homogeneous silicon slab into the photonic crystal slab. We clearly observed negative refraction of infrared light for TE-like modes in a broad wavelength range by using scanning near-field optical microscopy technology. The experimental results are in good agreement with finite-difference time-domain simulations. The results indicate the designed photonic crystal structure can serve as polarization beam splitter.

Cloning and characterization of DULP, a novel ubiquitin-like molecule from human dendritic cells.

We identified a novel ubiquitin-like molecule DULP from human dendritic cells. DULP contains a domain that shares 26% identity and 34% similarity with ubiquitin, and it possesses the corresponding Ile-44 hydrophobic patch used by mono- or poly-ubiquitin to interact with a ubiquitin-interaction motif (UIM) or ubiquitin-associated domain (UBA). Lysine residue corresponding to 6 of ubiquitin, which is involved in the formation of a multi-ubiquitin chain that can bind proteasomal subunit Rpn10/S5a, is also conserved in its ubiquitin-homology domain. However, DULP does not possess the highly conserved C-terminus Gly-Gly required for ubiquitin conjugation or the Lys-48 required for the formation of polyubiquitin chain to target substrates for degradation, suggesting it might be a novel ubiquitin-domain protein (UDP). DULP was found widely expressed in many cells and the ubiquitin-homology domain was not cleaved. We also confirmed that DULP expression was enriched in the nucleus and much weaker in the cytosol. Besides, we found that overexpression of DULP in 293T cells induced apoptosis, which might not be associated with the mitochondrial or proteasome pathway, with the specific mechanism remaining unclear. Further investigations are needed to identify the precise biological functions of DULP.