Fluorescence enhancement reaction of flavoxate hydrochloride (FX) in strong alkali solution was studied, the mechanism of the reaction was investigated, and a novel fluorimetric method for analysis of FX in drug sample was established. FX has no intrinsic fluorescence, but it can slowly produce fluorescence in strong alkali solution. Heating can promote the fluorescence enhancement reaction. In 3D fluorescence spectra of the decomposition product of FX, two fluorescence peaks, located respectively at excitation wavelengths λex/ emission wavelength λem =223/410 nm, and 302/410 nm, were observed. Using quinine sulfate as a reference, fluorescence quantum yield of the decomposition product was measured to be 0.50. The structural characteriza- tion and spectral analysis of the decomposition product reveal that ester bond hydrolysis reaction of FX is firstly occurred during heating process, forming 3-methylflavone-8-carboxylic acid (MFA), then a cleavage reaction of the γ-pyrone ring of MFA occurred, producing α, β-unsaturated ketone. This product includes adjacent hydroxyl benzoic acid group in its molecule, which can form intramolecular hydrogen bond under alkaline condition, so that increase the conjugate degree and enhance the rigidity of the molecule, and thereby cause fluorescence enhancement. Based on this fluorescence enhancement reaction, a fluorimetric method was proposed for the determination of FX. A linear calibration curve covered the concentration range 0.020 3-0.487 µg · mL. The regression equation was I(F) = 23.9 + 5357.3 c, with correlation coefficient r = 0.999 7 (n = 8), detection limit D = 1.1 ng · mL(-1). The method was applied to the analysis of FX tablets, with a spiked recovery rate of 100.2%. The reliability of the method was verified by a UV-spectrophotometric method.
Alkalies ; Calibration ; Chemistry, Pharmaceutical ; Flavoxate ; analogs & derivatives ; chemistry ; Fluorescence ; Limit of Detection ; Reproducibility of Results ; Solutions ; Tablets

Adult ; Arterio-Arterial Fistula ; pathology ; Coronary Vessels ; pathology ; Female ; Humans ; Pulmonary Artery ; pathology

We report a rare case of central retinal vein occlusion (CRVO) in pregnancy. There was dramatic deterioration of vision in both eyes through pregnancy despite repeated attempts of laser treatment and systemically controlled diabetes. Significant improvement was noted postpartum. Pregnancy is an aggravated factor of bilateral CRVO.
Pregnancy

Individuals deal with dying and death differently and may not experience the same journey. We investigated Kübler-Ross’ Five Stages of Grief on terminally ill patients to review the current applicability of the model among this population. The aims of this paper is to share information regarding the Five Stages of Grief, the emotions associated with the stages, and the challenges that terminally ill patients, namely those diagnosed with cancer, experience. Methods: Non-structured interviews were conducted among terminally ill patients located at the palliative ward for two years. Results: We found that terminally ill patients at the palliative ward were undergoing the Five Stages of Grief, and that the emotions associated with the stages were reported to be similar to the emotions proposed in the model and among the patients. Conclusion: Kübler-Ross’ Five Stages of Grief is still applicable among terminally ill patients. The thoughts regarding dying and death still remain negative, therefore, the change in the myths of dying and death are required to help improve the journey towards death.

Objective To simulate the mechanical environment of cells in vivo and study cellular signal transduction mechanisms. Methods A device was developed which could provide high cell yield, control the time, strain magnitude, direction and frequency of stretch, and applied 10% cyclic strain to cell culture substrate with stretch frequency at 1Hz. Results After being stretched, morphology and cytoskeleton of cells were altered. The major axis of cells and the alignment of stress fibers were vertical to the orientation of cyclic stretch. Conclusion This device provides versatile options for the study on the cellular responses of mechanical loading.

Objective:To investigate the expression of nicotinamide adenine dinucleotide (NAD +) digestive enzyme CD38 in normal and endotoxin-tolerant human monocyte THP-1 cell lines treated with lipopolysaccharide (LPS). Methods:(1) Normal THP-1 cells: The experiment and control group were treated with 100 ng/ml LPS for 1, 3, 6, 12 and 24 h or phosphate buffer for 24 h, respectively. Quantitative polymerase chain reaction (PCR) and Western blot were used to measure the expression of interleukin-6 (IL-6) and tumor necrosis factor (TNF) mRNA, CD38 mRNA and protein. (2) The induced endotoxin-tolerant THP-1 cells: ①The model of endotoxin-tolerant cells was established firstly by treating the THP-1 cells with 100 ng/ml LPS for 24 h. THP-1 cells treated with phosphate buffer were set as blank group. After further stimulating the two groups with LPS (100 ng/ml) for 3 h, mRNA levels of IL-6 and TNF were measured by quantitative PCR to determine whether the modeling was successful or not. ②In addition, the expression of CD38 mRNA were detected by quantitative PCR before and 12 h after LPS stimulation, and the expression of CD38 protein of these two groups were detected by western blotting before and 1, 6 h after LPS stimulation. Two independent samples t-test and repeated measurement analysis of variance were used for statistical analysis. Results:(1) In normal THP-1 cells, the mRNA expression levels of IL-6 and TNF in the LPS-stimulated cells were significantly higher than those of the control at all time points. And a higher expression level of CD38 mRNA and protein was observed in LPS-stimulated cells from 3 to 24 h compared with the control (mRNA at 3 h: 2.27±0.03 vs 1.00±0.18; protein at 3 h: 1.47±0.14 vs 1.00±0.16, both P<0.05). (2) Endotoxin-tolerant THP-1 cells: ①IL-6 and TNF mRNA levels in the model group were significantly lower than those in the blank group (both P<0.05), indicating that the endotoxin-tolerant THP-1 cell model was established successfully. ②Compared with the same points in the blank group, CD38 mRNA expression was upregulated in the model group before stimulating by LPS (14.18±1.19 vs 1.00±0.13, t=19.007) and 12 h after LPS stimulation (28.33±3.98 vs 7.61±0.88, t=8.803). Moreover, CD38 protein levels before stimulating by LPS (1.54±0.06 vs 1.00±0.10, t=7.796) and 1 h (1.59±0.09 vs 1.07±0.17, t=4.721), 6 h after LPS stimulation (2.48±0.09 vs 1.43±0.12, t=12.233) in the model group were all higher than those in the control group (all P<0.05). The intra-group comparison showed that in the model group the levels of CD38 mRNA at 12 h and CD38 protein at 6 h after LPS stimulation were significantly higher than those before (both P< 0.05). Conclusions:In both normal and endotoxin-tolerant THP-1 cells, LPS upregulates the expression of CD38, which is an NAD + digestive enzyme, and an indirect indicator of NAD + level in monocyte reinfection at the stage of immunosuppression. This study provides a preliminary reference for further investigation on the applicability of CD38 as a potential biological marker in the clinical diagnosis of neonatal sepsis.

Neuromyelitis optica (NMO) is a rare disorder in children with variable presentation. We report a 7-year-old boy who presented with bilateral retrobulbar optic neuritis and responded very well to treatment. He was also positive for aquaporin 4 (AQP4) antibodies, which is part of an emerging endophenotype within autoimmune neurological disorders in childhood.
Neuromyelitis Optica

Objective To evaluate the mutagenicity of hydrolysate of Meretrix meretrix Linnaeus soft tissue, so as to provide experimental basis for its exploitation.Methods Three mutagenicity tests were used to evaluate the mutagenic effects, including Ames test, CHL chromosome aberration assay and bone marrow micronucleus assay in mice.Results In Ames test, the revertant colonies numbers in each group were twice less than the numbers of spontaneous revertant colo-nies, five bacterial strains showed negative results with or without S9 activation, and the result of Ames test was negative. The CHL chromosome aberration assay and bone marrow micronucleus assay showed that the chromosome aberration rate and micronucleus rate of each dose group showed no significant difference compared with the negative control group, respec-tively ( P>0.05) .Conclusions Under this condition, the results show that all of the Ames test, chromosome aberration assay and bone marrow micronucleus assay are negative, and no mutagenicity is observed in the hydrolysate of Meretrix mer-etrix Linnaeus soft tissue.

Aim: To study the induction of apoptotic effect of sodium selenite on human lung cancer A549 cells and its mechanisms. Methods: A549 cells were exposed to different concentrations of sodium selenite for 24 h. MTT assay was applied to determine A549 cell proliferation. Inverted fluorescence microscope was used to investigate the morphological changes in A549 cells. Flow cytometry analysis was applied to assess the apoptotic rates of A549 cells. Laser confocal microscope was employed to measure the reactive oxygen species (ROS) fluorescence intensity. A multi-detection reader was used to determine the antioxidant parameter. Western blot was utilized to detect the expression of Keapl, Nrf2, HO-1 and Nrf2 in cytoplasm and nucleus. Results: MTT results showed that sodium selenite inhibited the proliferation of A549 cells in a concentration-dependent manner. After treatment with sodium selenite for 24 h, the apoptotic rate of A549 cells was markedly increased through Hoechst 33342 staining and flow cytometry measurement. Sodium selenite significantly up-regulated ROS and malondialdehyde (MDA) content and down-regulated the levels of superoxide dismutase (SOD) and glutathione (GSH). Meanwhile, sodium selenite treatment also reduced the expressions of Keapl, Nrf2 and HO-1 at protein levels and inhibited Nrf2 protein nuclear translocation in A549 cells. Conclusions: Treatment with sodium selenite induces A549 cells apoptosis, which may contribute to the anti-proliferation activity, induction of apoptosis and regulation of oxidative stress reaction and Keapl/Nrf2/ARE antioxidative signaling pathway expression.

ObjectiveTheaimofthisstudywastoprovideabetterpositivecontrolforallergictestbycomparing the allergic effect of two kinds of positive materials , human albumin and ovalbumin , on active systemic anaphylaxis in guinea pig.Methods Guinea pigs were randomly divided into 14 groups, and were given human albumin , ovalbumin (2, 10, 100 mg/animal), or 0.9%sodium chloride injection as test substances , to assess the symptoms and incidence of systemic allergic responses induced by different sensitizing substances in different challenge doses and different challenge intervals.Results In the range of 2 to 100 mg/animal, the guinea pigs showed a 100%incidence rate of positive allergic reaction to human albumin and ovalbumin , the severity of anaphylactic symptoms was increasing along with the increase of sensitizing doses and challenge doses , and the allergic reaction was more strong induced by the same dose of ovalbumin than human albumin .Conclusions Our findings indicate that in the active systemic anaphylaxis test in guinea pigs , we recommend ovalbumin as the positive control in a dose of 2 mg/animal.