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We investigated the efficacy of Ocimum basilicum (OB) essential oils for treating depression related behavioral, biochemical and histopathological changes caused by exposure to chronic unpredictable mild stress (CUMS) in mice and to explore the mechanism underlying the pathology. Male albino mice were divided into four groups: controls; CUMS; CUMS plus fluoxetine, the antidepressant administered for pharmacological validation of OB; and CUMS plus OB. Behavioral tests included the forced swim test (FST), elevated plus-maze (EPM) and the open ?eld test (OFT); these tests were performed at the end of the experiment. We assessed serum corticosterone level, protein, gene and immunoexpression of brain-derived neurotropic factor (BDNF) and glucocorticoid receptors (GRs) as well as immunoexpression of glial fibrillary acidic protein (GFAP), Ki67, caspase-3 in the hippocampus. CUMS caused depression in the mice as evidenced by prolonged immobility in the FST, prolonged time spent in the open arms during the EPM test and reduction of open field activity in the OFT. OB ameliorated the CUMS induced depressive status. OB significantly reduced the corticosterone level and up-regulated protein and gene expressions of BDNF and GR. OB reduced CUMS induced hippocampal neuron atrophy and apoptosis, and increased the number of the astrocytes and new nerve cells. OB significantly increased GFAP-positive cells as well as BDNF and GR immunoexpression in the hippocampus.  相似文献   
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Humoral defence factors in Indian river prawn, Macrobrachium malcolmsonii   总被引:1,自引:0,他引:1  
A preliminary study on humoral defence factors of Indian river prawn, Macrobrachium malcolmsonii was carried out. The serum of animals collected from intermoult stage had an average total protein content of 9.65 g dl(-1) and lysozyme-like activity of 0.04 unit ml(-1). The phenoloxidase activity in haemocyte lysate supernatant was triggered significantly (P < 0.05) by chitosan, Gram-positive and Gram-negative bacterial cells in comparison to other elicitors viz., levamisole, trypsin and glucan. The serum contained an agglutinin against Gram-negative bacteria and a haemagglutinin against a wide range of vertebrate erythrocytes. The haemagglutinin was stable over a wide range of pH (3.0-7.0) and temperatures (-30 degrees C to 60 degrees C). A 413 kDa N-acetyl galactosamine-specific haemagglutinin was purified by single step affinity chromatography and the protein was found to be calcium ion-dependent in nature and made up of five different subunits of varied molecular weights on denaturing SDS-PAGE.  相似文献   
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DNA damage induced in NC37 lymphoblasts by optical tweezers with a continuous-wave Ti:sapphire laser and a continuous-wave Nd:YAG laser (60-240 mW; 10-50 TJ/m2; 30-120 s irradiation) was studied with the comet assay, a single-cell technique used to detect DNA fragmentation in genomes. Over the wavelength range of 750-1064 nm, the amount of damage in DNA peaks at around 760 nm, with the fraction of DNA damage within the range of 750-780 nm being a factor of two larger than the fraction of DNA damage within the range of 800-1064 nm. The variation in DNA damage was not significant over the range of 800-1064 nm. When the logarithm of damage thresholds measured in the present work, as well as values reported previously in the UV range, was plotted as a function of wavelength, a dramatic wavelength dependence became apparent. The damage threshold values can be fitted on two straight lines, one for continuous-wave sources and the other for pulsed sources, irrespective of the type of source used (e.g. classical lamp or laser). The damage threshold around 760 nm falls on the line extrapolated from values for UV-radiation-induced damage, while the data for 800-1064 nm fall on a line that has a different slope. The change in the slope between 320 and 340 nm observed earlier is consistent with a well-known change in DNA-damaging mechanisms. The change observed around 780 nm is therefore suggestive of a further change in the mechanism(s). The data from this work together with our previous measurements provide, to the best of our knowledge, the most comprehensive view available of the DNA damage produced by microfocused light.  相似文献   
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A pulsed (17 nanoseconds) Nd:YAG laser (1064 nm) was used to inject impermeable dyes (propidium iodide andiodide and merocyanine 540) and a plasmid (pEGFP-N1) encoding green fluorescent protein (GFP) into human breast adenocarcinoma cells (MCF-7). The cell membrane integrity and viability were fully preserved in this laser-assisted transfer.  相似文献   
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Acardiac anomaly spectrum   总被引:1,自引:0,他引:1  
BACKGROUND: Acardiac anomaly spectrum is a rare congenital malformation found in monozygotic twin pregnancy. Besides the absence of heart, the condition is associated with variable grades of developmental disruption. Thus, no two cases are similar. METHODS: This case report is based on physical examination and autopsy findings. RESULTS: The twin had acardia and partial development of head and face. There was complete absence of upper extremities. CONCLUSIONS: The twin reversed arterial perfusion (TRAP) theory is the most accepted etiology of the disorder. Normally, the cephalic pole is the most severely affected, being most distal to the retrograde perfusion. In acardia, partial development of head, face, and brain is usually associated with the development of the upper extremities. However, in the present case, there was extensive cephalic development in the absence of upper extremity development.  相似文献   
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Background and aims

Elemental uptake in serpentine floras in eastern North America is largely unknown. The objective of this study was to determine major and trace element concentrations in soil and leaves of three native pseudo-metallophyte C4 grasses in situ at five sites with three very different soil types, including three serpentine sites, in eastern USA.

Methods

Pseudo-total and extractible concentrations of 15 elements were measured and correlated from the soils and leaves of three species at the five sites.

Results

Element concentrations in soils of pseudo-metallophytes varied up to five orders of magnitude. Soils from metalliferous sites exhibited higher concentrations of their characteristic elements than non-metalliferous. In metallicolous populations, elemental concentrations depended on the element. Concentrations of major elements (Ca, Mg, K) in leaves were lower than typical toxicity thresholds, whereas concentrations of Zn were higher.

Conclusions

In grasses, species can maintain relatively low metal concentrations in their leaves even when soil concentrations are richer. However, in highly Zn-contaminated soil, we found evidence of a threshold concentration above which Zn uptake increases drastically. Finally, absence of main characteristics of serpentine soil at one site indicated the importance of soil survey and restoration to maintain serpentinophytes communities and avoid soil encroachment.
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