Isolation and identification of vapA-absent Aeromonas salmonicida in diseased snakehead Channa argus in China.

Aeromonas salmonicida is the typical pathogen causing furunculosis, reported widely in salmonids. Because of multiple serotypes, the control of A. salmonicida-caused disease has increasingly received much attention. Recently, A. salmonicida infection was reported in non-salmonid fish species. Here, a pathogenic A. salmonicida, named as As-s, was isolated from cultured snakehead (Channa argus) in a local fish farm in Shandong, China. As-s displayed clear hemolysis, amylase, and positive catalase activities, and grew at a wide range of temperatures (10-37 °C) and pH values (5.5-8.5). As-s was highly sensitive to cefuroxime sodium, ceftriaxone, ceftazidime, piperacillin, and cefoperazone and also apparently sensitive to chloramphenicol, erythromycin, and 25% cinnamaldehyde. The Virulence array protein gene cloning' results suggested that As-s has this gene compared with the other two vapA-containing strains, despite a close relationship of these strains via phylogenetic analysis. Severe ulcers on skin, muscle, and abnormal liver, and hemorrhage in pectoral/ventral fins and anal region were observed, and exophthalmos were also noticed in infected juvenile snakehead, as well as necrosis and infiltration of blood cells emerged in the internal organs using pathological section. In addition, As-s caused high mortality in snakehead, consistently with its immune gene response. This study reports the first isolation of vapA-absent A. salmonicida in snakehead.

Vascular ring and sling in a fetus who developed esophageal and airway compression after birth.

Vascular ring and sling are congenital anomalies of the vascular structure in the thorax with a prevalence of 2.4/10,000 live births. Double aortic arch (DAA), right aortic arch with left ductus arteriosus and aberrant left subclavian artery (RAA-ALSA), and pulmonary artery sling (PAS) are the three common types of vascular ring and sling. These anomalies can be isolated or accompanied by intracardiac malformation. The presence of both vascular ring and PAS is extremely rare. Here, we report a fetus who was prenatally diagnosed with PAS and RAA-ALS, and developed symptoms due to esophageal and airway compression after birth.

The opioid receptor triple agonist DPI-125 produces analgesia with less respiratory depression and reduced abuse liability.

Opioid analgesics remain the first choice for the treatment of moderate to severe pain, but they are also notorious for their respiratory depression and addictive effects. This study focused on the pharmacology of a novel opioid receptor mixed agonist DPI-125 and attempted to elucidate the relationship between the δ-, µ- and κ-receptor potency ratio and respiratory depression and abuse liability. Five diarylmethylpiperazine compounds (DPI-125, DPI-3290, DPI-130, KUST202 and KUST13T02) were selected for this study. PKA fluorescence redistribution assays in CHO cells individually expressing δ-, µ- or κ-receptors were used to measure the agonist potency. The respiratory safety profiles were estimated in rats by the ratio of ED50 (pCO2 increase)/ED50 (antinociception). The abuse liability of DPI-125 was evaluated with a self-administration model in rhesus monkeys. The observed agonist potencies of DPI-125 for δ-, µ- and κ-opioid receptors were 4.29±0.36, 11.10±3.04, and 16.57±4.14 nmol/L, respectively. The other four compounds were also mixed agonists with varying potencies. DPI-125 exhibited a high respiratory safety profile, clearly related to its high δ-receptor potency. The ratio of the EC50 potencies for the µ- and δ-receptors was found to be positively correlated with the respiratory safety ratio. DPI-125 has similar potencies for µ- and κ-receptors, which is likely the reason for its reduced abuse potential. Our results demonstrate that the opioid receptor mixed agonist DPI-125 is safer and less addictive than traditional µ-agonist analgesics. These findings suggest that the development of δ>µâˆ¼κ opioid receptor mixed agonists is feasible, and such compounds could represent a promising class of potent analgesics with wider therapeutic windows.

[Effects of Side-effect Attenuation Prescriptions on Cyclophosphamide-induced Myelosuppression in Mice].

OBJECTIVE: To determine the effects of Side-effect Attenuation Prescriptions on the levels of white blood cells (WBC), hemoglobin (HGB) and platelet (PLT) in peripheral blood of mice influenced by cyclophosphamide (CTX). METHODS: Mice were randomly divided into 6 groups: normal control group, myelosuppression group induced by CTX (model group), recombinant human granulocyte colony stimulating factor (G-CSF) group, and Side-effect Attenuation Prescriptions group (experimental groups with high, middle, and low dosages). Marrow depressed models were established by injecting CTX intraperitoneally (40 mg/kg, once/d, 10 d) to the mice. High, middle, and low dosage experimental groups received 40 g/kg, 20 g/kg, and 10 g/kg Side-effect Attenuation Prescriptions once a day for two weeks, respectively. Mice in the G-CSF group were given G-CSF (50 µg/kg) by hypodermic injection three days before blood sampling. Levels of WBC, HGB and PLT counts in peripheral bloods of the mice were detected at 7 d and 14 d after the marrow depressed models were established. RESULTS: The Side-effect Attenuation Prescriptions slowed down the decline of blood levels of WBC, HGB and PLT induced by CTX (P < 0.05), and accelerated the recovery of WBC and HGB levels compared with model group at 14 d (P < 0.05). CONCLUSION: The Side-effect Attenuation Prescriptions can accelerate recovery of WBC, HGB and PLT in peripheral bloods of mice.

Seawater immersion exacerbates the pathological changes caused by incisive corneal injury in rabbit eyes.

Background: Seawater immersion complicates injuries suffered during maritime conflicts and eye injury is one of most common injuries on the battlefield. This study aimed to delineate the pathophysiological changes in the cornea after corneal injury combined with seawater immersion. Methods: The left eye of New Zealand White rabbits was injured with firecracker and a 3-mm long whole-layer incision in the center of the cornea parallel to the corneal limbus, followed by seawater immersion. The right eye was used as a control. The histology of the cornea and the inflammatory cytokine/chemokine levels in the aqueous humor were examined on days 1 and 7 after injury. The protein levels of aquaporin 1, 3, and 5 were assessed by immunohistochemical staining 7 days after injury. The expression and activation of nuclear factor κB (NF-κB) were examined by Western blot analysis. Results: Seawater immersion exacerbated penetrating explosive injury caused progressive tissue damage of the cornea and ocular inflammation, with drastic increases in the expression of cytokines/chemokines in the aqueous humor, which was mediated by the upregulation and activation of NF-κB. Furthermore, corneal protein levels of aquaporin 1, 3, and 5 were significantly increased after incisive injury and seawater immersion. Conclusions: These data demonstrated that the combination of incisive injury and seawater immersion is a dangerous situation and effective care strategies should be developed for the management of such maritime injuries.

[Insulin-like growth factor-1 induced activation and expression of signal transducers and activators of transcription-3 in scleral fibroblast of guinea pigs].

OBJECTIVE: To investigate the expression of signal transducers and activators of transcription 3 (STAT3) in sclera fibroblast of guinea pigs for understanding whether STAT3 signaling transduction pathway induced by the insulin-like growth factor-1 (IGF-1) was constitutively activated. METHODS: Immunocytochemical staining was used to determine the protein levels of STAT3 and P-STAT3 (activated STAT3) in scleral fibroblasts. RT-PCR was used to detect the mRNA of STAT3. The effects of IGF-1 on scleral fibroblast proliferation were measured by MTT assay. RESULTS: Immunocytochemical staining and RT-PCR revealed that STAT3 protein and mRNA were over-expressed in the cells which contained constitutively activated STAT3 signaling transduction pathway (t=-6.925, -10.179 and 9.363; P<0.001). The results of MTT showed that IGF-1 induced fibroblasts proliferation significantly at concentrations of 0.5, 1.0, 10.0 microg/L (P<0.05). CONCLUSION: STAT3 signaling transduction pathway is constitutively activated in the treated scleral cells by IGF-1, suggesting that STAT3 signaling transduction pathway may play a critical role in the occurrence of myopia and sclera remodeling.

An UPLC-MS/MS method for the analysis of glimepiride and fluoxetine in human plasma.

A sensitive and rapid ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed to determine glimepiride (GPD) and fluoxetine (FLU) in human plasma using diazepam as the internal standard (IS) simultaneously. The presented method used an Acquity UPLC BEH C18 column for chromatographic separation with tandem mass spectrometric detection on a QTrap5500 mass spectrometer operated in positive ESI mode. The mobile phase is a mixture of acetonitrile and 1% formic acid in water with gradient elution at a flow rate of 0.40mL/min. The GPD, FLU and IS were eluted at 1.46, 1.27 and 1.39min, respectively. The MRM transitions of m/z 491.3→126.3 and m/z 310.5→148.1 were used to quantify for GPD and FLU, respectively. The linearity of this method was found to be within the concentration range of 2.5-300ng/mL and 0.1-20ng/mL for GPD and FLU in human plasma, respectively. The intra- and inter-day precision (RSD%) were less than 10.3% and accuracy (RE%) was within ±7.3%. The matrix effect were 95.3-100.7% for GPD and FLU. GPD and FLU were sufficiently stable under all relevant analytical conditions. The method was also successfully applied to the clinical samples after a single oral dose of 2mg GLP and 40mg FLU in patients.

Expression and activity determination of human angiostatin (k1-3) in culture cells and larvae of silkworm.

Angiostatin (k1-3) gene was inserted into Bombyx mori baculovirus transfer vector pBacPAK8 and cotransfected with lineared DNA of Bm-BacPAK6 virus into BmN cells. The homologous recombination occurred inside the cells, and the recombinant virus BacPAK-angiostatin was expressed, as identified by DNA dot blotting. The BmN cells and fifth instars were infected by the recombinant virus BacPAK-angiostatin; expression product was run in the SDS-PAGE, and its immunoreactivity was determined by using ELISA and Western blotting. The bio-activity of the protein product was determined by using human umbilical vein endothelial cells ( ECV304 ) proliferation test in vitro and by using CAM vascular inhibition test in vivo. The expression activity achieved the highest point at the 72nd hour in BmN cells (22 u / 2x10(6) cells) and at 144th hour in larvae (159 u/ml). At the concentration of 2.5 u/ml, angiostatin induced apoptosis of endothelial cells in 24 h and also inhibited angiogenesis in CAM.

Determination of cephalomannine in rat plasma by gradient elution UPLC-MS/MS method.

A rapid, sensitive and selective ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was developed and validated for the determination and pharmacokinetic investigation of cephalomannine in rat plasma. Sample preparation was accomplished through a simple one-step deproteinization procedure with 0.2 mL of perchloric acid-methanol (1:9, v/v) to a 0.1 mL plasma sample. Plasma samples were separated by UPLC on an Acquity UPLC BEH C18 column using a mobile phase consisting of acetonitrile-0.1% formic acid in water with gradient elution. The total run time was 2.0 min and the elution of cephalomannine was at 1.60 min. The detection was performed on a triple quadrupole tandem mass spectrometer in the multiple reaction-monitoring (MRM) mode using the respective transitions m/z 832.8→264.1 for cephalomannine and m/z 812.6→286.0 for 10-DAT (internal standard), respectively. The calibration curve was linear over the range of 10-2,000 ng/mL with a lower limit of quantitation (LLOQ) of 10 ng/mL. Mean recovery of cephalomannine in plasma was in the range of 80.9-85.3%. Intra-day and inter-day precision were both <11.2%. This method was successfully applied in pharmacokinetic study after intravenous administration of 5.0mg/kg cephalomannine in rats.

[Expression of polyprotein of infectious bursal disease virus in Bombyx mori].

Segment A of the genome of infectious bursal disease virus(IBDV) encodes structure protein VP2 and VP3 and protease VP4. In this study a polyprotein gene of IBDV was inserted into a Bombyx mori baculovirus transfer vector pAcHLT--C and contransfected into BmN cells with linear genome DNA of virus Bm-BacPAK6. Dot hybridization suggested that the segment A of the virus genome was inserted in the genome of Bm-BacPAK6. The silkworm of fifth instars were infected by the recombinant virus and the immunogenicity of the infected larvae's blood were examined with ELISA, SDS-PAGE and Western blotting. It appears that the recombinant polyprotein has the property of immunoreactivity and the expression in larvae reached the pick 5-day post infection.