Role of Bushen Huoxue Formula and transplanted endothelial progenitor cells play in promoting endplate microcirculation and attenuating intervertebral disc degeneration.

Objective: To explore whether Bushen Huoxue Formula (BSHXF) improves the angiogenesis ability of transplanted endothelial progenitor cells (EPCs) in endplate and its potential mechanism in delaying intervertebral disc degeneration (IDD). Methods: BSHXF was analyzed via Ultra-High Performance Liquid Chromatography (UPLC). Rabbit axial compression lumbar IDD models were constructed and the effects of BSHXF, EPCs, and their combination in IDD were determined by MRI, histological evaluation, TUNEL, and immunofluorescence assays. Additionally, CCK-8 assay, flow cytometry, and tube formation assay were used to evaluate EPCs viability, proliferation, cell cycle and the angiogenesis ability of EPCs between groups. Results: BSHXF and transplanted EPCs both attenuate the process of IDD in the rabbit model assessed by MRI, HE staining and Masson staining. TUNEL-positive NP cells were significantly reduced in the BSHXF group, EPCs group, and EPC + BSHXF group compared to the model group (P < 0.05), with the EPC + BSHXF group showing the most significant therapeutic effect. Immunofluorescence detection showed that VEGF, CD34 expression and quantity of microvessels in the endplate significantly increased in the EPC + BSHXF group compared to all the other groups (P < 0.05). Besides, the CCK-8 assay showed an upregulation of EPC viability and the tube formation assay demonstrated a significant increase in tube length and branching in EPCs cultured with BSHXF-containing serum (P < 0.05). Furthermore, BSHXF-containing serum increased VEGF expression in EPCs cultured in vitro (P < 0.05). Conclusions: Both BSHXF and EPCs transplantation play an important role in increasing endplate angiogenesis and attenuating IDD. BSHXF can enhance the viability and tube-forming ability of EPCs and endplate microcirculation.

Network Pharmacology with Metabolomics Study to Reveal the Mechanisms of Bushen Huoxue Formula in Intervertebral Disc Degeneration Treatment.

Background: Intervertebral disc degeneration (IVDD) is a pathophysiological process that leads to severe back pain or neurological deficits. The Bushen Huoxue Formula (BSHXF) is a traditional herbal remedy widely used to treat diseases related to IVDD. However, its pharmacological mechanism needs further exploration. Objective: This study aimed to elucidate the mechanisms through which BSHXF treats IVDD-related diseases by integrating metabolomics with network pharmacology. Methods: Network pharmacology was utilized to identify potential targets of BSHXF against IVDD. Additionally, an animal model of needle puncture-induced disc degeneration was established to assess the effect of BSHXF. Mice were randomly assigned to the sham group, model group, and BSHXF group. Various techniques, including PCR, CCK-8 assay, MRI, histological examinations, and immunohistochemical analyses, were employed to evaluate degenerative and oxidative stress conditions in mouse disc tissue and cultured nucleus pulposus (NP) cells. UHPLC-HRMS/MS was used to differential distinct metabolites in the disc tissue from different groups, and MetaboAnalyst 5.0 was employed to enrich the metabolic pathways. Results: Through network pharmacology, 15 core proteins were identified through protein-protein interaction (PPI) network construction. Functional enrichment analysis highlighted the critical role of BSHXF in addressing IVDD by influencing the response to oxidative stress. Furthermore, experimental evidence demonstrated that BSHXF significantly improved the pathological progression of IVDD and increased oxidative stress markers SOD-1 and GPX1, both in the disc degeneration model and cultured NP cells. Metabolomics identified differential metabolites among the three groups, revealing 15 metabolic pathways between the sham and model groups, and 13 metabolic pathways enriched between the model and BSHXF groups. Conclusion: This study, integrating network pharmacology and metabolomics, suggests that BSHXF can alleviate IVDD progression by modulating oxidative stress. Key metabolic pathways associated with BSHXF-mediated reduction of oxidative stress include the citrate cycle, cysteine and methionine metabolism, alanine, aspartate and glutamate metabolism, glycine, serine and threonine metabolism, D-glutamine and D-glutamate metabolism, glutathione metabolism, and tryptophan metabolism. While this research demonstrates the therapeutic potential of BSHXF in reducing oxidative stress levels in IVDD, further research is needed to thoroughly understand its underlying mechanisms.

A randomized controlled trial: The efficacy and safety of Bushen Huoxue formula in the management of lower back pain from lumbar disc herniation.

BACKGROUND: Lower back pain (LBP) arising from lumbar disc herniation (LDH) poses a challenging health issue, often necessitating therapeutic interventions. Bushen Huoxue formula (BSHXF) has proved as a potential treatment option with great clinical effect. However, comprehensive investigations into its efficacy and safety in conjunction with celecoxib for managing LBP from LDH are lacking. The objective of this article is to investigate the efficacy and safety of BSHXF in the management of patients with LBP from LDH. METHODS: This single center, randomized clinical trial was conducted from March 2023 to September 2023 and all patients suffered from LBP of LDH. Participants were randomly assigned to the BSHXF group (celecoxib and BSHXF) or the control group (celecoxib and placebo). The patients received treatment for 2 weeks. Assessment was conducted before treatment, the last day of the treatment, 4 weeks and 8 weeks after the treatment. Oswestry Disability Index (ODI), Visual Analog Scale (VAS), Roland-Morris Disability Questionnaire (RMDQ), Timed up and go test (TUGT), trunk range of movement (Trunk ROM), Hospital Anxiety and Depression Scale (HADS) were used for the evaluation. RESULTS: A total of 206 subjects completed treatment, among whom 104 participants were randomized to the BSHXF group and 102 participants were randomized to the control group. There were no significant differences between groups in terms of the observed indicators (P > .05). After treatment, patients in BSHXF group obtained significant lower scores at 2-week, 4-week, 8-week of VAS, ODI, RMDQ, TUGT, Trunk ROM and HADS than the baseline data (P < .05). The ODI score was significantly lower than the control group at 2-week, 4-week, 8-week (2w: 11.30 ±â€…5.80 vs 14.23 ±â€…6.33, P < .001; 4w: 10.95 ±â€…4.93 vs 13.54 ±â€…6.35, P < .001; 8w: 10.27 ±â€…5.25 vs 12.84 ±â€…6.57, P = .002). Similarly, the scores of VAS, RMDQ, TUGT, Trunk ROM scores of the BSHXF group markedly decreased at 2, 4, and 8-week when compared to their control group (P < .05). Furthermore, no significant difference showed up in the score of HADS between the between the BSHXF and the control group after treatment (P > .05). CONCLUSION: This randomized clinical trial found that BSXHF can help significantly improve the clinical outcomes of celecoxib including pain intensity reduction and lumbar function improvement in LBP patients.

Lipopolysaccharides of Brucella suis S2 Impaired the Process of Decidualization in Early Pregnancy in Mice.

Brucellosis is a notorious zoonotic disease caused by Brucella, which can lead to reproductive diseases in humans and animals, such as infertility and abortion. Lipopolysaccharides (LPS) are the main virulence factor of Brucella. LPS derived from Brucella are different and non-classical and are less toxic and less active than LPS isolated from E. coli. However, the effects and possible mechanisms of Brucella LPS-caused pregnancy loss remain to be revealed. In the present study, we investigated the effects of Brucella suis S2 LPS on early pregnancy loss in mice. The results indicated that embryo implantation failure was induced by Brucella LPS treatment in a dose-dependent manner. The injection of Brucella LPS mainly resulted in fibrinolysis in the decidual area of the uterus on the 6th day post coition (dpc), infiltration of large granular cells among the decidual cells near the embryo on the 8th dpc, a large number of gaps in the decidual area, and cell necrosis around the embryo. In addition, the expression of Cyclin D3 mRNA in the uterus on the 7th and 8th dpc and IGFBP-1 mRNA and the progesterone receptor in the uterus on the 6th and 7th dpc were also inhibited. Moreover, the expression of decidualization marker Cyclin D3 and decidualization prolactin-associated protein (dPRP) in endometrial stromal cells were also inhibited by Brucella LPS treatment in vitro. In summary, Brucella LPS affect the process of endometrial decidualization in mice by affecting the structure of the decidua and the expression of decidual marker factors in endometrial stromal cells.

The ratiometric fluorescent sensor based on the mixture of CdTe quantum dots and graphene quantum dots for quantitative analysis of silver in drinks.

Silver nanoparticles can be used in antibacterial packaging or disinfection. Research has shown that sugary fluid induces the leaching of silver nanoparticles into water, which may be harmful to humans. Single wavelength fluorescence analysis has been used for quantitative analysis of silver nanoparticles but suffers from low specificity and poor anti-interference ability. In this paper, a ratiometric fluorescence sensor system (GCS) was used for the detection of Ag+, which realized both visual detection and quantitative analysis of silver in drinks. The color changes of GCS with different concentrations of Ag+ are distinguishable and easy to analyze. There is also a good linear relationship between the concentrations of Ag+ and varieties of F424 nm/F570 nm, and the lowest detection limit reached 0.2266 nmol/L. This GCS shows good selectivity and recovery and could be used for the detection of Ag+ in drink samples.

One-pot preparation of Mn3O4/GSH/CdTe quantum dots complex for T1-weighted MRI/fluorescence detection of H3PO4.

Magnetic resonance and fluorescence dual mode imaging with both advantages of high sensitivity and high spatial resolution, which could realize real-time, in situ, and dynamic imaging, is very suitable for detecting small molecules. And the synthesis of imaging materials with good imaging performance has become the core content. In this paper, based on biomimetic mineralization technology, GSH has been used as a material to design a one-pot method for the preparation of Mn3O4/GSH/CdTe quantum dots composites (MGQ in short). Furthermore, MGQ with good T1MR and fluorescence response to the variety concentration of H3PO4, has been used for quantitative analysis of H3PO4 in serum. And the lowest limit detection could reach 0.1769 nmol/L for fluorescent detection, 0.02207 mol/L for MRI detection. MGQ would be applied as a sensor in diagnostic and clinical applications.

The preparation of MnO2/BSA/CdTe quantum dots complex for ratiometric fluorescence/ T1-weighted MRI detection of H2O2.

Hydrogen peroxide, as the second messenger in cells, plays an essential regulatory role in cell proliferation, differentiation and migration. How to effectively identify H2O2 signals, and detect H2O2 in circulating tumor cells, are essential for the early diagnosis of tumors. Herein a fluorescence and T1-weighted MR dual-mode imaging material, named MnBQ, has been successfully prepared and characterized. Based on the chemical redox reaction between MnBQ and H2O2, a fluorescence/T1-weighted MRI dual-mode sensor has been developed for quantitative analysis of H2O2, of which the lowest limit detection obtained from fluorescence and MRI could reach 2.841 µmol/L and 43.85 µmol/L, respectively. This imaging sensor has dual advantages of high sensitivity and high spatial resolution, which could be a good candidate for monitoring of H2O2 in vivo.

Clinical outcomes for andersson lesion in patients with ankylosing spondylitis by transforaminal thoracolumbar intervertebral fusion surgery.

BACKGROUND: Andersson lesion (AL) is a rare complication of ankylosing spondylitis (AS). Its clinical outcome of surgical treatment needs further exploration. OBJECTIVE: To evaluate the clinical and radiological outcomes of transforaminal thoracolumbar intervertebral fusion (TTIF) in the treatment of AS patients with thoracolumbar AL. METHODS: Fourteen patients with thoracolumbar AL who suffered from back pain, spinal instability or kyphotic deformity were retrospectively recruited. The clinical outcomes were evaluated with Visual Analog Scale (VAS) and Oswestry Disability Index (ODI). Radiological outcomes were measured with local kyphotic (LK) angle and general kyphotic (GK) angle. RESULTS: Before surgical treatment for the AL patients, their VAS score and ODI score was 8.0 ± 0.2 and 64.0 ± 6.9, respectively. After TTIF surgery, VAS score of the patients was improved to 2.4 ± 0.5 (p< 0.01) and ODI score was decreased to 17.0 ± 3.7 (p< 0.01). One patient with neurological deficit showed an improvement in the Frankel grade from C to D and all others were grated E-level before and after surgery. For radiological outcomes, patients' LK angle was reduced from 18.5 ± 7.2 to 11.0 ± 6.4 (p< 0.01) and GK angle was reduced to 38.6 ± 8.8 from 42.8 ± 10.4 (p< 0.01) at the 1-year follow-up. CONCLUSION: For AS patients with thoracolumbar AL, we propose that TTIF is an effective and safe operative treatment, which can achieve good fusion, satisfactory radiological and clinical outcomes.

N,S-GQDs mixed with CdTe quantum dots for ratiometric fluorescence visual detection and quantitative analysis of malachite green in fish.

N,S-GQDS was prepared through citric acid cracking method from thiourea and citric acid, a ratiometric fluorescence sensor was constructed for the detection of malachite green based on CdTe quantum dots and N,S-GQDs. Interestingly the color of this ratiometric fluorescence sensor could change from red to blue under UV light upon exposure to different amounts of malachite green, and this ratiometric fluorescence sensor could be used for visual detection of malachite green. Fluorescence emission spectra of this ratiometric fluorescence sensor with different amounts of malachite green were also analyzed, and there was a good linear relationship between F460nm/F666nm and concentrations of malachite green, the lowest limit detection could reach 0.4597 nmol/L. Furthermore, this proposed ratiometric sensor is used for quantitative analysis of malachite green in fish sample. Results shown that this ratiometric fluorescence sensor is feasibility and practicality for both visual detection and quantitative analysis of malachite green.

Theoretical design and characterization of new terpolymer donors based on PTB7Ir for high-efficiency triplet-material-based organic photovoltaics.

In the current work, eleven terpolymer donors with different electron-withdrawing groups were designed and investigated based on the reported PTB7Ir to screen outstanding donors for triplet-material-based organic photovoltaics (T-OPVs). Geometry structures, frontier molecular orbital energy levels, energy driving forces (ΔE L-L), absorption spectra, energy differences between S1 and T1 states (ΔE ST), and driving forces of the triplet charge recombination (-ΔG CRT) of PTB7Ir and designed 1-11 systems were evaluated by DFT and TD-DFT methods to estimate the light absorption abilities and the charge transfer dynamics. The results show that designed 5, 8, 10 and 11 possess larger spin-orbit couplings (SOC) affinity and smaller ΔE ST and -ΔG CRT values, which could effectively suppress the triplet charge recombination process at the donor/acceptor interface. Excitingly, the designed terpolymer 10 presents enhanced light absorption, revealing that it will be a promising donor candidate for high-performance T-OPV devices. Moreover, the results can provide theoretical guidelines to predict new terpolymer donors of T-OPVs.

Undifferentiated Pleomorphic Sarcoma with Neoplastic Fever: A Retrospective Study.

BACKGROUND: Although the annual incidence of undifferentiated pleomorphic sarcoma (UPS) is extremely low, it can be subdivided into different subtypes. UPS with fever of unknown origin (also known as neoplastic fever) is a specific subtype of UPS, which shows certain clinical features that differentiate it from other UPS subtypes. However, no studies have focused on this rare UPS subtype. This study retrospectively analyzed the clinical data of patients with UPS to provide a reference for the diagnosis and treatment of UPS with neoplastic fever. METHODS: This study included patients with UPS who were diagnosed and treated between June 2012 and June 2018. We examined whether these patients had a history of neoplastic fever. The characteristics of patients with UPS with neoplastic fever were summarized and analyzed. RESULTS: We reviewed the medical records of 183 patients with UPS. Seven (3.83%) of these patients had neoplastic fever. In patients with UPS with neoplastic fever, the primary lesions were located in the extremities and across the muscle space. In these patients, magnetic resonance imaging showed necrosis within the tumor body and extensive soft tissue edema around the tumor body. Patients with UPS with neoplastic fever had a lower metastasis rate (14.29% vs 44.94%) and a higher 3-year survival rate (85.71% vs 59.55%) than those without neoplastic fever. CONCLUSION: UPS with neoplastic fever is characterized by intratumoral necrosis and extensive edema of the surrounding soft tissues. Patients with UPS with neoplastic fever may have a better prognosis than those without neoplastic fever.

Balloon kyphoplasty combined with posterior pedicle screw fixation for the treatment of osteoporotic thoracolumbar burst fractures.

BACKGROUND: Osteoporotic thoracolumbar burst fracture (TLBF) is difficult to treat due to its high rate of postoperative implant failure. This study was designed to evaluate the clinical effect of balloon kyphoplasty with polymethylmethacrylate (PMMA) and posterior pedicle screw fixation for the treatment of osteoporotic TLBF. METHODS: Between February 2012 and May 2016, 24 consecutive patients with osteoporotic TLBFs were included in this study, all of whom suffered incomplete neurologic deficit. They were managed with transpedicular balloon kyphoplasty, PMMA augmentation, and posterior pedicle screw fixation. Scanning with X-ray and computed tomography (CT) were performed to evaluate the kyphotic deformity with the Cobb angle and vertebral body height loss (VBHL) of the injured vertebra. Visual analogue scale (VAS) and the Oswestry Disability Index (ODI) were adopted to assess the pain and dysfunction levels before and after the operation. RESULTS: All participants were followed up for an average of 18 months and those with incomplete neurologic deficit recovered completely. The Cobb angle significantly improved from a preoperative angle of 23.2°±3.6° to 5.3°±2° after operation and to 5.7°±2.2° at the last follow up (P<0.05). The VBHL improved from 56.8%±7.8% before operation to 9.1%±1.6% after operation and to 9.7%±1.9% at the last follow up (P<0.05). The visual analog scale (VAS) score decreased from 8.8±0.9 before operation to 2.5±0.4 after operation and to 1.4±0.4 at the last follow up (P<0.05). The ODI score decreased from 88.6%±3.5% before the operation to 32.3%±3.7% after operation and to 17.5%±1.8% at the last follow up (P<0.05). CONCLUSIONS: Balloon kyphoplasty combined with posterior pedicle screw fixation was an effective treatment for osteoporotic TLBFs. This procedure can reconstruct 3 spinal columns using a single approach with less blood loss, short operation time, and rapid recovery. Ruptures of the posterior vertebral wall should not be a contraindication of this procedure. TRIAL REGISTRATION: Chinese Clinical Trial Registry (NO.: ChiCTR1900026157).

Radiological and clinical outcomes of balloon kyphoplasty for osteoporotic vertebral compression fracture in patients with rheumatoid arthritis.

BACKGROUND: This study was conducted to investigate the outcomes and complications of balloon kyphoplasty (KP) for the treatment of osteoporotic vertebral compression fracture (OVCF) in patients with rheumatoid arthritis (RA) and compare its radiological and clinical effects with OVCF patients without RA. METHODS: Ninety-eight patients in the RA group with 158 fractured vertebrae and 114 patients in the control group with 150 vertebrae were involved in this study. Changes in compression rate, local kyphotic angle, visual analog scale (VAS) and Oswestry disability index (ODI) scores, conditions of bone cement leakage, refracture of the operated vertebrae, and new adjacent vertebral fractures were examined after KP. In addition, patients in the RA group were divided into different groups according to the value of erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), and whether they were glucocorticoid users or not to evaluate their influence on the outcomes of KP. RESULTS: KP procedure significantly improved the compression rate, local kyphotic angle, and VAS and ODI scores in both RA and control groups (p<0.05). Changes in compression rate and local kyphotic angle in the RA group were significantly larger than that in the control group (p<0.05), and patients with RA suffered more new adjacent vertebral fractures after KP. The outcomes and complications of KP from different ESR or CRP groups did not show significant differences. The incidence of cement leakage in RA patients with glucocorticoid use was significantly higher than those who did not take glucocorticoids. In addition, RA patients with glucocorticoid use suffered more intradiscal leakage and new adjacent vertebral fractures. CONCLUSIONS: OVCF patients with RA obtained more improvement in compression rate and local kyphotic angle after KP when compared to those without RA, but they suffered more new adjacent vertebral fractures. Intradiscal leakage and new adjacent vertebral fractures occurred more in RA patients with glucocorticoid use. TRIAL REGISTRATION: Retrospectively registered.

Combination of a graphene SERS substrate and magnetic solid phase micro-extraction used for the rapid detection of trace illegal additives.

Surface enhanced Raman scattering (SERS) is an ultra-sensitive spectroscopy technique, which can provide rich structural information for a great number of molecules, while solid phase micro-extraction (SPME) is an efficient method for sample pretreatment in analytical chemistry, particularly in a micro-system. In the present report, a silver-loaded and graphene-based magnetic composite (Fe3O4@GO@Ag) was fabricated for use as both a SERS-active substrate and SPME material. The π-π stacking and fluorescence quenching abilities of GO make the composite a perfect candidate for SERS in analyzing real-world samples. Therefore, through combining the magnetic nanoparticles with a SPME device, we have developed a pretreatment method named as disperse magnetic solid phase micro-extraction (Dis-MSPME). In comparison to traditional SPME, the proposed Dis-MSPME realized solid phase micro-extraction from a dispersive system and largely improved the extraction efficiency. Furthermore, by combining the advantages of both Dis-MSPME and SERS we have proposed a new detection method called Dis-MSPME-SERS. Finally, as an example, the illegal additive chloramphenicol (CAP) was successfully detected in aqueous solution with low LOQ and LOD values (1.0 × 10-8 and 1.0 × 10-10 M, respectively), which was finalized within 10 min based on the proposed Dis-MSPME-SERS method. Therefore, a simpler, more efficient and sensitive approach to realize enrichment, magnetic separation and detection, all-in-one, for the detection of illegal additives has been reported, which will be promising towards the detection of trace amounts of substance in micro-systems.

The determination of nitrite by a graphene quantum dot fluorescence quenching method without sample pretreatment.

A method for quantitative analysis of nitrite was achieved based on fluorescence quenching of graphene quantum dots. To obtain reliable results, the effects of pH, temperature and reaction time on this fluorescence quenching system were studied. Under optimized conditions, decrease in fluorescence intensity of graphene quantum dots (F0 /F) showed a good linear relationship with nitrite concentration between 0.007692-0.38406 mmol/L and 0.03623-0.13043 µmol/L; the limits of detection were 9.8 µmol/L and 5.4 nmol/L, respectively. Variable temperature experiments, UV absorption spectra and thermodynamic calculations were used to determine the quenching mechanism, and indicated that it was an exothermic, spontaneous dynamic quenching process. This method was used to analyse urine samples, and showed that it could be applied to analyse biological samples.

Density functional theory investigation on iridium(iii) complexes for efficient blue electrophosphorescence.

The geometrical structures, electronic structures, optoelectronic properties and phosphorescence efficiencies of four blue-emitting phosphors [Ir(fpmi)2(pyim)] (1), [Ir(pyim)2(fpmi)] (2), [Ir(fpmi)2(fptz)] (3), [Ir(tfmppz)2(pyim)] (4), [fpmi = 1-(4-fluorophenyl)-3-methylimdazolin-2-ylidene-C,C2'; pyim = 2-(1H-imidazol-2-yl)pyridinato; fptz = 5-(trifluoromethyl-2H-1,2,4-triazol-3-yl)pyridine; tfmppz = 1-(4-trifluoromethylphenyl)pyrazolyl] were investigated by DFT and TDDFT methods. We first optimized geometrical structures in the ground and lowest triplet states, and computed the absorption and emission spectra of 1 and 5[Ir(fpmi)2(pypz)] [pypz = 2-(1H-pyrazol-5-yl)pyridinato], which have been synthesized and characterized in a laboratory, using three functionals, B3LYP, CAM-B3LYP, and M062X. The calculation results were compared with relevant experimental data to assess the performance of the functionals. The suitable methods and functionals were then applied to study properties of the three other complexes. The HOMOs of 1-3 are composed of d(Ir) and π(cyclometalated ligands), however, the HOMO of 4 resides on the pyim ligand, while the LUMOs of all four complexes are dominantly localized on the chelating ligands. The calculated absorption results show that the corresponding absorption peaks for the four mainly studied complexes are almost at the same positions, however, the absorption intensities of the bands differ largely from each other. The lowest energy emissions of the four complexes are localized at 507, 512, 468, and 513 nm, respectively. In order to estimate their efficiencies, we carried out simplified radiative rate constant calculations. It turns out that complex 3, which possesses the shortest emission wavelength and the largest radiative rate constant (k r) value, can be considered as a highly efficient blue-emitting iridium(iii) complex.

An azo-coupling reaction-based surface enhanced resonance Raman scattering approach for ultrasensitive detection of salbutamol.

To date, great achievements with GC-MS, HPLC-MS, and fluorescence biosensing techniques have been made to detect illegal additives of salbutamol (SAL) in swine meat. However, these methods are not suitable for rapid on-site screening due to either costly instruments or rather complicated and/or time consuming sample pretreatments. Herein, a simple, rapid and ultrasensitive approach based on an azo-coupling reaction and surface-enhanced resonance Raman scattering (SERRS) is presented. By combining with a magnetic SERS substrate, an indirect detection for SAL, with a LOD of 1.0 × 10-11 M (2.39 pg mL-1), was realized. Moreover, a colorimetric method for naked eye detection was successfully carried out for rapid screening of SAL in concentrations higher than 2.09 × 10-5 M (5 µg mL-1). In addition, the proposed method was successfully applied for the rapid determination of SAL in real swine meat. The entire process, including pretreatment, coupling reaction and SERRS detection, was performed within 7 min. Moreover, the SERRS fingerprint band being specific to corresponding functional group guarantees the selectivity for the target molecule. Therefore, the proposed strategy in the present study offers a new way to identify trace amounts of analytes, such as SAL as well as other illegal additives in health-related products and food.

Development and Characterization of Canine Distemper Virus Monoclonal Antibodies.

Five canine distemper virus monoclonal antibodies were developed by immunizing BALB/c mice with a traditional vaccine strain Snyder Hill. Among these monoclonal antibodies, four antibodies recognized both field and vaccine strains of canine distemper virus without neutralizing ability. One monoclonal antibody, 1A4, against hemagglutinin protein of canine distemper virus was found to react only with vaccine strain virus but not field isolates, and showed neutralizing activity to vaccine strain virus. These monoclonal antibodies could be very useful tools in the study of the pathogenesis of canine distemper virus and the development of diagnostic reagents.

Isolation and genomic characterization of a canine parainfluenza virus type 5 strain in China.

A canine parainfluenza virus type 5 strain was isolated from a lung sample from a diseased dog. The genome sequene of this isolate, named HeN0718, was determined and compared tho those of other previously reported canine parainfluenza viruses. Unlike previously reported viruses, the HeN0718 strain contained several nucleotide mutations in the SH gene that led to a frame shift in the open reading frame. Phylogenetic analysis based on the complete virus genome and the P, F, and HN genes showed that HeN0718 was genetically closest to D277, a Korean strain that was isolated in 2008.

A fluorescence-quenching method for quantitative analysis of Ponceau 4R in beverage.

CdTe quantum dots was synthesized and used to quantitative analysis of Ponceau 4R in solution. With the excitation wavelength of 380nm the emission of CdTe quantum dots was quenched obviously by Ponceau 4R. In order to detect Ponceau 4R in mild condition the influences of fluorescence emission wavelength of CdTe quantum dots, pH value, temperature and reaction time were examined to establish the experimental condition. The linear response of the fluorescence intensity of CdTe quantum dots to Ponceau 4R allowed the quantitative analysis of Ponceau 4R in a range of 2.5-25µg/mL, and the limit of detection for Ponceau 4R was 0.025µg/mL. In addition, the responsive mechanism of this reaction system was investigated in detail by using the modified Stern-Volmer equation and thermodynamic calculation. Particularly, this method was used to quantitatively analyze the real sample, which indicated that this method could be more widely applied in similar samples.