Laser sheet microscopy is a widely used imaging technique for imaging the three-dimensional distribution of a fluorescence signal in fixed tissue or small organisms. In laser sheet microscopy, the stripe artifacts caused by high absorption or high scattering structures are very common, greatly affecting image quality. To solve this problem, we report here a two-step procedure which consists of continuously acquiring laser sheet images while vertically displacing the sample, and then using the variational stationary noise remover (VSNR) method to further reduce the remaining stripes. Images from a cleared murine colon acquired with a vertical scan are compared with common stitching procedures demonstrating that vertically scanned light sheet microscopy greatly improves the performance of current light sheet microscopy approaches without the need for complex changes to the imaging setup and allows imaging of elongated samples, extending the field of view in the vertical direction.
In Optical Projection Tomography (OPT), if the rotational center deviates from the central line of the image and this offset is not corrected during the reconstruction, serious blurring will happen in the final 3-dimensional (3D) result. Therefore, the high-precision rotational center location method is very important for OPT. However, existing methods are inconvenient because they need active participation during the location process. Thus, the automated and fast rotational center location method is in great demand. In preliminary work, we proposed an automated rotational center location method which consisted of a high Specimen Signal Intensity (SSI) sinogram selection and a coarse-fine search. Our method had an accuracy of about 1/4 pixel. However, further robustness analysis of our method is lacking. In this paper, we have investigated its location errors on sinograms with various SSIs and analyzed whether it was effective to use high SSI sinograms for rotational center location. Moreover, we have also discussed the relationship between location errors and the starting rotational angles. The experimental results showed that our coarse-fine method was robust under different starting angles. Meanwhile, the high SSI sinogram selection scheme improved the location precision.
The prevalence of 23 putative virulence factors among fluoroquinolone-susceptible and -resistant Haemophilus parasuis isolates was analyzed. Putative hemolysin precursor, fimbrial assembly chaperone, and type I site-specific restriction modification system R subunit genes were more prevalent among fluoroquinolone-resistant H. parasuis isolates than among fluoroquinolone-susceptible H. parasuis isolates. Fluoroquinolone resistance may be associated with an increase in the presence of some virulence factors.
Taurine, a conditionally essential amino acid, plays a critical role in cardiovascular function. Here we examined the effect of taurine on mitochondria and endoplasmic reticulum in rat cardiomyocytes during glucose deprivation (GD). Data showed that cell viability, intracellular taurine contents, and taurine transporter expression were decreased during GD. In contrast, an increase in reactive oxygen species and intracellular Ca(2+) contents was observed. GD also caused disrupted mitochondrial membrane potential, apoptotic cell death, and dissociation of unfolded protein response (UPR)-relative proteins in cardiomyocytes. Signal transduction analysis showed that Bcl-2 family protein balance was disturbed, caspase-12 was activated and UPR-relative protein levels were up-regulated. Moreover, pre-treatment with 80 mM exogenous taurine attenuated GD effect in cardiomyocytes. Our results suggest that taurine have beneficial effects on inhibiting mitochondria-dependent cell apoptosis and UPR-associated cell apoptosis and might have clinical implications on acute myocardial infarction in future.
To improve the oil yield of Chuanxiong volatile oils and keep their quality same as that of oils prepared by steam distillation (SD) for short), a new technology of coupling water extraction and rectification (WER for short) was applied to isolate Chuanxiong volatile oils. The oil yield, as well as GC-MS chromatogram of the volatile oils extracted by WER and SD were compared. The oil yield of WER (0.50%) was that of SD (0.20%). There were 21 common constituents in the two kinds of volatile oils, which occupied 98.94% of the oils extracted by SD, 98.80% of that by WER, respectively. Moreover, the relative percentage of the common constituents was almost the same. The results indicate that WER could not only increase the oil yield of Ligusticum chuanxiong, but also keep the quality of the oils accord with that extracted by SD.
Lead is the non-essential trace element in the human body, and it has been confirmed that drinking water is one of the sources of lead in human body. In the research, based on the sensitive colour reaction of lead with I(-)-EV(+)-PVA, a simple, sensitive, accurate and portable method for the determination of trace lead in drinking waters was proposed. Chemicals and physicals had been optimized in detail. The apparent molar absorption coefficient was up to 7.4x10(5) mol L(-1) cm(-1). The developed method provided a linearity range over 5-80 microg L(-1). The regression deviation was between 0.71% and 2.33%. The 3sigma detection limit was 0.9 microg L(-1). Close to the quantitation limit for the analyte the relative standard deviation was 1.10% (n=10) at 40 microg L(-1). The method developed here for analysis of lead yielded results that were comparable with those of the GFAAS.
Bisphenol-A (BPA), an environmental endocrine disruptor, has attracted attention because of its adverse effects on the brain and behavioral development. Previous evidence indicates that perinatal exposure to low levels of BPA affects anxiety-like and cognitive behaviors in adult rodents. The present study aims to investigate the changes of anxiety- and depression-like behaviors of perinatally exposed mice in adulthood following the gestational (gestation days 7 to 20) or lactational (postnatal days 1 to 14) exposure to BPA (0.4 or 4 mg/kg/d). The results indicated that both gestational and lactational exposures to BPA increased anxiety and depression-like behavior in mice of both sexes. The females with gestational exposure exhibited an increased anxiety-like state in the four models tested, including the open field, dark-light transition task, mirrored maze, and elevated plus maze tasks. Furthermore, the females with lactational exposure and the males with gestational exposure exhibited an anxiogenic-like behavior in two models, whereas the males with lactational exposure exhibited an anxiogenic-like behavior only in the elevated plus maze test. The results of the forced swim task showed that gestational exposure markedly increased the immobile time in both sexes, and the same effect was induced by lactational exposure only with 4 mg/kg/d BPA. Furthermore, western blot analyses showed that both gestational and lactational exposures inhibited the expression of the AMPA receptor subunit GluR1 in the hippocampus and amygdala in mice of both sexes, whereas the level of the NMDA receptor subunit NR1 was increased in the amygdala following gestational exposure but was reduced in the hippocampus of the females with lactational exposure. These results suggest that both gestational and lactational exposures to BPA increased anxiety- and depression-like behaviors of adult mice of both sexes. In addition gestational exposure exhibited a stronger effect on anxiety-like state in females. The altered levels of AMPA and NMDA receptors in the hippocampus and amygdala may be associated with BPA-induced behavioral changes.
Estrogen has great potential as a therapeutic agent in focal ischemic brain injury. Amino acids as energy resources and neurotransmitters in the central nervous system are crucial for proper neuronal function and excitability. The proton-coupled amino acid transporter PAT1 has clear potential in drug absorption. In this paper, human brain PAT1 was cloned and expressed in Xenopus oocytes. The effects of estradiol on the activity of PAT1 were investigated. Glycine-induced membrane currents mediated by PAT1 were measured using the two-electrode voltage clamp technique. The amplitude of the glycine-elicited current was decreased progressively with increasing concentrations of ?-estradiol. A concentration-dependent outwards current of PAT1 was also detected by the presence of ?-estradiol. We conclude that estrogen attenuates the activity of PAT1 by directly closing PAT1 channel. Our results may provide an additional mechanism for estrogen on neurotransmission and neuronal metabolism during ischemic injury.
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