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1.
Claudins are thought to be major components of tight junctions (TJs), and claudin-5 and -12 are localized at TJs of the blood-brain barrier (BBB). Claudin-5-deficient mice exhibit size-selective (<800 Da) opening of the BBB. The purpose of this study was to clarify the expression levels of claudin-5 and -12 in rat brain capillary endothelial cells, and to examine the ability of claudin-5 to form TJs in cultured rat brain capillary endothelial cells (TR-BBB). Expression of claudin-5 mRNA in rat brain capillary fraction was 751-fold greater than that of claudin-12. The level of claudin-5 mRNA in the rat brain capillary fraction (per total mRNA) was 35.6-fold greater than that in whole brain, while the level of claudin-12 mRNA was only 13.9% of that in whole brain, suggesting that expression of claudin-12 mRNA is not restricted to brain capillaries. Transfection of TR-BBB cells with the claudin-5 gene afforded TR-BBB/CLD5 cells, which showed no change in expression of claudin-12 or ZO-1, while the expressed claudin-5 was detected at the cell-cell boundaries. The permeability surface product of [(14)C]inulin at a TR-BBB/CLD5 cell monolayer was significantly smaller (P < 0.01) than that for the parental TR-BBB cells, and the values of the permeability coefficient (Pe) were 1.14 x 10(-3) and 11.6 x 10(-3) cm/min, respectively. These results indicate that claudin-5, but not claudin-12, is predominantly expressed in brain capillaries, and plays a key role in the appearance of barrier properties of brain capillary endothelial cells.  相似文献   
2.
Angiogenesis is indispensable to guide a regeneration of good periodontal tissue in the wound healing after periodontal surgery. Hepatocyte growth factor is well known for a strong angiogenic factor and it may play important roles in the periodontal tissue during periodontal wound healing. In exploring the promotion of angiogenesis in the periodontal ligament, proliferative and tubulogenic responses of endothelial cells to hepatocyte growth factor and to soluble factors secreted by fibroblasts were investigated. Pavement-shaped cells isolated from a human periodontal ligament were identified as the endothelial cell by their granular immunoreactivity for factor VIII. The proliferation of the endothelial cells was accelerated by the addition of hepatocyte growth factor or fibroblast-conditioned medium, and far more by adding both than either. The endothelial cells seeded on the agar containing both hepatocyte growth factor and fibroblast products formed a dense network in a shorter time than on the agar containing either. The endothelial cells in the dense network took a tube-like structure with lumen and were covered with laminin. These results suggest that hepatocyte growth factor administered into the regenerating periodontal tissue may promote, synergistically with local factors produced by the activated fibroblast, the proliferation and tubulogenesis of the remaining endothelial cells.  相似文献   
3.
Physiological, biochemical and histological indices in Clarias gariepinus broodstock, and teratogenic indices in embryos exposed to sublethal concentrations of naphthalene, phenanthrene and pyrene were investigated in 2014 using a static-renewal bioassay protocol. Phenanthrene (1.41 mg l?1) was the most toxic, followed by pyrene (1.53 mg l?1) and naphthalene (7.21 mg l?1), based on 96 h LC50 values. Hepatosomatic indices were significantly higher in naphthalene- and pyrene-treated males compared with solvent controls, whereas fecundity in females was significantly lower by factors of 2.4 (naphthalene), 2.8 (phenanthrene) and 2.4 (pyrene), compared with controls. Catalase levels were lower in female phenanthrene-treated fish compared with controls. Histological alterations observed in PAH-treated fish include oedema, inflammatory cells, epithelial lifting and hyperplasia in the gills, vacuolation, haemosiderin pigments and sinusoidal congestion in the liver, and degenerated zona radiata in the ovary. Teratogenic effects were not observed, as evidenced by the lack of histological alterations in embryos spawned from pre-exposed broodstock. Sex-specific responses and the utility of biomarkers at cellular and individual levels of organisation are therefore demonstrated for holistic evaluations of polycyclic aromatic hydrocarbons in ecotoxicological studies.  相似文献   
4.

Introduction

Accurate, continuous, left ventricular stroke volume (SV) measurements can convey large amounts of information about patient hemodynamic status and response to therapy. However, direct measurements are highly invasive in clinical practice, and current procedures for estimating SV require specialized devices and significant approximation.

Method

This study investigates the accuracy of a three element Windkessel model combined with an aortic pressure waveform to estimate SV. Aortic pressure is separated into two components capturing; 1) resistance and compliance, 2) characteristic impedance. This separation provides model-element relationships enabling SV to be estimated while requiring only one of the three element values to be known or estimated. Beat-to-beat SV estimation was performed using population-representative optimal values for each model element. This method was validated using measured SV data from porcine experiments (N = 3 female Pietrain pigs, 29–37 kg) in which both ventricular volume and aortic pressure waveforms were measured simultaneously.

Results

The median difference between measured SV from left ventricle (LV) output and estimated SV was 0.6 ml with a 90% range (5th–95th percentile) −12.4 ml–14.3 ml. During periods when changes in SV were induced, cross correlations in between estimated and measured SV were above R = 0.65 for all cases.

Conclusion

The method presented demonstrates that the magnitude and trends of SV can be accurately estimated from pressure waveforms alone, without the need for identification of complex physiological metrics where strength of correlations may vary significantly from patient to patient.  相似文献   
5.
The trypanosomatid previously described as Crithidia roitmani is characterized here at the ultrastructural and biochemical levels. The data indicates that the parasite belongs to the Herpetomonas genus, and we therefore suggest the flagellate to be denominated as Herpetomonas roitmani n. comb. Cladistic analysis of isoenzyme data generated by eight different enzymes showed that the parasite presented a distinct banding pattern and could be grouped with some Herpetomonas spp., but not with Crithidia spp., used as reference strains. Accordingly, when the parasites were grown for longer periods in Roitman's defined medium, expontaneous differentiation from promastigotes to opisthomastigotes (typical of the Herpetomonas genus) occurred. Transmission electron microscopy revealed the presence of bacterium-like endosymbionts in the cytoplasm of all evolutive forms of the parasite. All morphological alterations characteristic of endosymbiont-bearing trypanosomatids could be observed.  相似文献   
6.
In thyrotoxic women with pregnancy, serum somatomedin C (SmC) concentration was markedly elevated (mean +/- SD 13.57 +/- 4.66 U/ml) compared to thyrotoxic women without pregnancy (1.24 +/- 1.09 U/ml), non-pregnant euthyroid women previously treated for hyperthyroidism (0.87 +/- 0.30 U/ml), normal subjects with pregnancy (6.08 +/- 3.36 U/ml) and pregnant euthyroid women previously treated for hyperthyroidism (5.98 +/- 1.52 U/ml). Since SmC/growth hormone ratio was significantly more in thyrotoxic pregnant women than in normal pregnant women and euthyroid pregnant women previously treated for hyperthyroidism, and since human placental lactogen (HPL), human chorionic gonadotropin (HCG) and prolactin (PRL) do not crossreact with SmC antibody, it is suggested that excess thyroid hormone during pregnancy results in excessive hepatic somatomedin C production.  相似文献   
7.
Anti-thyroid antibodies in patients with hyperprolactinemia.   总被引:1,自引:0,他引:1  
To clarify the possible role of prolactin in the regulation of immune responses in man, we measured circulating anti-thyroid antibodies in 172 normal subjects, 84 patients with prolactinoma and 63 patients with acromegaly with normal thyroid and adrenocortical functions. Frequencies of positive thyroidal microsome and thyroglobulin antibodies were significantly (p < 0.05 and p < 0.01, respectively) higher in women with prolactinoma (20.6% and 20.6%) than in normal women (7.5% and 4.7%). Men with prolactinoma had a significantly (p < 0.05) higher frequency of positive thyroglobulin antibody (18.8%) than normal men (1.5%). When the subjects were divided by decade, women with prolactinoma in the 4th decade had significantly (p < 0.05) higher frequencies of positive thyroidal microsome and thyroglobulin antibodies (30.8% and 30.8%) than normal women of corresponding age (3.7% and 3.7%). In contrast, there was no significant difference in the frequencies of positive anti-thyroid antibodies in patients with acromegaly and in normal subjects. Analysis of the peripheral lymphocyte population revealed that patients with prolactinoma had a higher percentage of B cells than normal subjects, while there was no significant difference in the percentages of total T lymphocytes or in the helper and suppressor T cell ratios in the two groups of subjects. These results suggest that prolactin regulates humoral immune responses in man directly by stimulating B lymphocytes or indirectly by inhibiting suppressor T lymphocyte activity.  相似文献   
8.
9.
In an attempt to study the effects of methimazole treatment on immunologic abnormality of hyperthyroidism of Graves' disease, TSH receptor antibody (TRab), anti-DNA antibody and HLA-DR were measured in untreated patients with hyperthyroidism of Graves' disease and treated patients with methimazole for 2 years, using peripheral blood. In untreated patients, all 3 parameters elevated above normal. Three parameters decreased 2 years after methimazole treatment, but the magnitude of decrease was more in T3-suppressible patients than in T3-unsuppressible patients. However, both anti-DNA antibody and HLA-DR were significantly more in T3-suppressible patients than in normal subjects. It is suggested that immunologic abnormalities should largely be improved before remission of Graves' disease can be obtained.  相似文献   
10.
Periodontitis is a common inflammatory disease causing destruction of periodontal tissues. It is a multifactor disease involving genetic factors and oral environmental factors. To determine genetic risk factors associated with aggressive periodontitis or severe chronic periodontitis, single nucleotide polymorphisms (SNPs) in multiple candidate genes were investigated in Japanese. We studied 134 patients with aggressive periodontitis, 117 patients with severe chronic periodontitis, and 125 healthy volunteers without periodontitis, under case-control setting, and 310 SNPs in 125 candidate genes were genotyped. Association evaluation by Fisher's exact test (p < 0.01) revealed statistically significant SNPs in multiple genes, not only in inflammatory mediators (IL6ST and PTGDS, associated with aggressive periodontitis; and CTSD, associated with severe chronic periodontitis), but also in structural factors of periodontal tissues (COL4A1, COL1A1, and KRT23, associated with aggressive periodontitis; and HSPG2, COL17A1, and EGF, associated with severe chronic periodontitis). These appear to be good candidates as genetic factors for future study.  相似文献   
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