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181.
Concentrations of P, K, Ca, Mg, Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn were measured in rhizomes and fronds of the fern Athyrium filix-femina in relation to the concentrations of the same elements in soils developed on various parent rocks in the Góry Kaczawskie mountains (southwest Poland). This species was sampled from sites on greenstone, sandstone, metadiabase, crystalline limestone, rhyolite, metamudstone, mica and sericite schists and quartzite to verify the hypothesis that the elemental composition of A. filix-femina is different on each type of parent rock. We verified this hypothesis utilising the neural network method (SOFM). The self organising feature map (SOFM) was used to classify parent rock, soil, rhizomes and fronds of A. filix-femina based on the concentrations of elements. Elevated concentrations of elements accumulated in A. filix-femina were influenced by the geochemistry of different parent rock types on which this species grew indicating the bio indicative potential of this plant. SOFM was able to distinguish all types of parent rock based on the chemical composition of A. filix-femina. Therefore SOFM could be a future tool in recognising the type of plant substrate in the Góry Kaczawskie mountains by analysing the concentrations of elements in this species.  相似文献   
182.

Background

During a proper execution of dMLC plans, there occurs an undesired but frequent effect of the dose locally accumulated by tissue being significantly different than expected. The conventional dosimetric QA procedures give only a partial picture of the quality of IMRT treatment, because their solely quantitative outcomes usually correspond more to the total area of the detector than the actually irradiated volume.

Aim

The aim of this investigation was to develop a procedure of dynamic plans verification which would be able to visualize the potential anomalies of dose distribution and specify which tissue they exactly refer to.

Materials & methods

The paper presents a method discovered and clinically examined in our department. It is based on a Gamma Evaluation concept and allows accurate localization of deviations between predicted and acquired dose distributions, which were registered by portal as well as film dosimetry. All the calculations were performed on the self-made software GammaEval, the γ-images (2-dimensional distribution of γ-values) and γ-histograms were created as quantitative outcomes of verification.

Results

Over 150 maps of dose distribution have been analyzed and the cross-examination of the gamma images with DRRs was performed.

Conclusions

It seems, that the complex monitoring of treatment would be possible owing to the images obtained as a cross-examination of γ-images and corresponding DRRs.  相似文献   
183.
Literature data indicate an association between the presence of Helicobacter spp. in the liver and the development of hepatocellular carcinoma (HCC). However, the role of H. pylori infections in chronic liver diseases (CLD) remains controversial. The aim of this study was to detect Helicobacter spp. DNA in patients with CLD, and to investigate the host response to the presence of the bacterium in the liver. Helicobacter spp. DNA was detected in 59% samples. H.pylori was the most prevalent species (94%). We estimated the expression level of IL-1 and IL-8 genes. The presence of Helicobacter spp. did not have a significant effect on the gene expression of IL-8 and IL-1.  相似文献   
184.
The involvement of both apolipoprotein E (apoE) and mitochondria in lipid metabolism is widely recognized, however there is surprisingly scarce data about the putative mitochondrial action(s) of this protein. The aim of the study was to screen the alterations in liver mitochondrial proteome caused by apoE deficiency. We applied 2DE-LC-MS/MS methodology to investigate the changes in liver mitochondrial protein expression in 6-months old apoE(-/-) mice as compared to C57BL/6J controls. ApoE(-/-), but not C57BL/6J mice developed visible atherosclerotic changes in aorta and mild, diffuse steatosis of the liver. Collectively, 18 differentially expressed proteins were identified in mitochondria, related to apoptosis, antioxidant and detoxifying mechanisms of mitochondria, as well as lipid metabolism and transport. In conclusion, differential proteomic approach revealed several lines of proteomic evidence that mitochondrial function in the liver of apoE(-/-) mice could be altered as a result of overlapping of pathological and compensatory changes in expression of proteins.  相似文献   
185.
Follicle-stimulating hormone (FSH) and triiodothyronine (T3) are known regulatory factors of spermatogenesis initiation. Connexin 43 (Cx43) is the most ubiquitous constitutive protein of gap junctions in the testis. This study evaluates the effects of the hyperstimulation of FSH and T3 during testicular maturation on Cx43 expression in the testis. The newborn, male Wistar rats were divided randomly into four experimental groups: FSH group-daily injections of FSH 7.5?IU/animal; T3 group-100?μg T3/kg body weight; FSH+T3 group-both substances; A control group-received vehicles in the same volume. Proliferating cell nuclear antigen immunohistochemistry and toluidine blue staining were used to determine the germ cell proliferation and degeneration. Cx43 immunolocalization was evaluated to find Cx43 maturational changes. Under FSH treatment, the proliferation rate was high so the total number of Sertoli cells increased with a low level of degeneration and lumen formation. T3 stimulation evoked a reduction in the proliferation rate and a decrease in Sertoli cell number but with intensive formation of lumen. T3+FSH inhibited the proliferation rate and stimulated lumen formation together with degeneration, which negatively influenced the number of germ cells in the seminiferous epithelium. We conclude that T3 action seems to be particularly connected with the maturation of Cx43 gap junctions. FSH stimulates maturation of Sertoli cell function, but this effect may take place regardless of the presence of Cx43-dependent intercellular communication. The hyperstimulation of both FSH and T3 damages Cx43 connections and hence evokes regressional changes in the seminiferous epithelium.  相似文献   
186.

Background

The use of biologic mesh to repair abdominal wall defects in contaminated surgical fields is becoming the standard of practice. However, failure rates and infections of these materials persist clinically. The purpose of this study was to determine the mechanical properties of biologic mesh in response to a bacterial encounter.

Methods

A rat model of Staphylococcus aureus colonization and infection of subcutaneously implanted biologic mesh was used. Samples of biologic meshes (acellular human dermis (ADM) and porcine small intestine submucosa (SIS)) were inoculated with various concentrations of methicillin-resistant Staphylococcus aureus [105, 109 colony-forming units] or saline (control) prior to wound closure (n = 6 per group). After 10 or 20 days, meshes were explanted, and cultured for bacteria. Histological changes and bacterial recovery together with biomechanical properties were assessed. Data were compared using a 1-way ANOVA or a Mann-Whitney test, with p<0.05.

Results

The overall rate of staphylococcal mesh colonization was 81% and was comparable in the ADM and SIS groups. Initially (day 0) both biologic meshes had similar biomechanical properties. However after implantation, the SIS control material was significantly weaker than ADM at 20 days (p = 0.03), but their corresponding modulus of elasticity were similar at this time point (p>0.05). After inoculation with MRSA, a time, dose and material dependent decrease in the ultimate tensile strength and modulus of elasticity of SIS and ADM were noted compared to control values.

Conclusion

The biomechanical properties of biologic mesh significantly decline after colonization with MRSA. Surgeons selecting a repair material should be aware of its biomechanical fate relative to other biologic materials when placed in a contaminated environment.  相似文献   
187.
188.
Mitochondria represent a major source of reactive oxygen species (ROS), particularly during resting or state 4 respiration wherein ATP is not generated. One proposed role for respiratory mitochondrial uncoupling proteins (UCPs) is to decrease mitochondrial membrane potential and thereby protect cells from damage due to ROS. This work was designed to examine superoxide production during state 4 (no ATP production) and state 3 (active ATP synthesis) respiration and to determine whether uncoupling reduced the specific production of this radical species, whether this occurred in endothelial mitochondria per se, and whether this could be modulated by UCPs. Superoxide formation by isolated bovine aortic endothelial cell (BAE) mitochondria, determined using electron paramagnetic resonance spectroscopy, was approximately fourfold greater during state 4 compared with state 3 respiration. UCP1 and UCP2 overexpression both increased the proton conductance of endothelial cell mitochondria, as rigorously determined by the kinetic relationship of respiration to inner membrane potential. However, despite uncoupling, neither UCP1 nor UCP2 altered superoxide formation. Antimycin, known to increase mitochondrial superoxide, was studied as a positive control and markedly enhanced the superoxide spin adduct in our mitochondrial preparations, whereas the signal was markedly impaired by the powerful chemical uncoupler p-(trifluoromethoxyl)-phenyl-hydrazone. In summary, we show that UCPs do have uncoupling properties when expressed in BAE mitochondria but that uncoupling by UCP1 or UCP2 does not prevent acute substrate-driven endothelial cell superoxide as effluxed from mitochondria respiring in vitro.  相似文献   
189.
Human plasmacytoid dendritic cells (PDC) are key sentinels alerting both innate and adaptive immune responses through production of huge amounts of alpha/beta interferon (IFN). IFN induction in PDC is triggered by outside-in signal transduction pathways through Toll-like receptor 7 (TLR7) and TLR9 as well as by recognition of cytosolic virus-specific patterns. TLR7 and TLR9 ligands include single-stranded RNA and CpG-rich DNA, respectively, as well as synthetic derivatives thereof which are being evaluated as therapeutic immune modulators promoting Th1 immune responses. Here, we identify the first viruses able to block IFN production by PDC. Both TLR-dependent and -independent IFN responses are abolished in human PDC infected with clinical isolates of respiratory syncytial virus (RSV), RSV strain A2, and measles virus Schwarz, in contrast to RSV strain Long, which we previously identified as a potent IFN inducer in human PDC (Hornung et al., J. Immunol. 173:5935-5943, 2004). Notably, IFN synthesis of PDC activated by the TLR7 and TLR9 agonists resiquimod (R848) and CpG oligodeoxynucleotide 2216 is switched off by subsequent infection by RSV A2 and measles virus. The capacity of RSV and measles virus of human PDC to shut down IFN production should contribute to the characteristic features of these viruses, such as Th2-biased immune pathology, immune suppression, and superinfection.  相似文献   
190.
INTRODUCTION: Renal insufficiency is the most common etiology of secondary hyperparathyroidism. In case of resistance for conservative treatment, methods of choice are surgical intervention or percutaneous ethanol injections. AIM OF THE STUDY: The aim of the study was to evaluate usefulness of percutaneous ethanol injection therapy in the treatment of patients with secondary hyperparathyroidism. MATERIAL AND METHODS: We performed percutaneous 96% ethanol injections under USG guideance in 51 patients: 22 women (mean age 49.6 years) and 29 men (46.6 yrs). The base level of parathormone was 689.35 pg/ml. We managed to visualize one parathyroid gland in 34 patients, 2 in 12, 3 in 5 patients. The mean volume of a single gland was 0,8 cm3. All the injections were performed with the use of needle number 6. We repeated injections in case of no effects. One injection was performed in 18 patients, 2 in 18, 3 in 13, 5 in 1 and 6 in 1 patient. Before and after the treatment patients were examined with USG, scintigraphy and densitometry. Serum levels of calcium (Ca), phosphorus (P), parathormone (PTH) and alkaline phosphatase (FA) activity were also obtained. The main criteria for success was decrease in parathormone level of 50% or more in comparison with pre-injection level or to less than 200 pg/ml. RESULTS: In the whole group of patients after the first month, positive results were observed in 67%. There were no changes in 23%, and PTH level increased in 10%. After 6 months-positive results in 53%, no change in 35% and increase in 12%. We noted the best results in patients with PTH less than 800 pg/ml-72% of them had positive results after 1 as far as after the 6 month. CONCLUSIONS: Percutaneous ethanol injections are valuable method of treatment of secondary hyperparathyroidism. The best results can be obtained if PTH level is less than 800 pg/ml, one parathyroid gland dominating over the rest is visualised in USG, and if patient responds after 1 or at least 2 injections.  相似文献   
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