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41.
In this work, the chitin was treated by 0.1 N HCl, 0.5 N NaOH, and 8% sodium hypochlorite. The change of the molecular structure was studied by Fourier Transform Infrared Spectroscopy (FTIR) in the wavenumber range (400–4000 cm−1). The absorption bands were assigned and the crystallinity index was calculated from the ratio of the absorbance C–N band at 1378 cm−1 and CH at 2925 cm−1. The data indicated that, the crystallinity index of chitin is higher than that of treated chitin which is due to the hydrolysis of some acetamide group. Also, treating with alkali causes a swelling of chitin chains. The dielectric properties such as dielectric constant (ε′), dielectric loss (ε″) and AC electrical conductivity were measured and discussed as a function of frequencies (0.1 kHz–3 MHz). The dielectric constant (ε′) was decreased with increasing frequencies due to the dielectric dispersion. β-relaxation was observed and discussed from the dielectric loss (ε″). The results of AC conductivity showed that, at high frequency, the conductivity increased with increasing frequencies and its interpreted in term of hopping conduction. 相似文献
42.
Kozic D Medic-Stojanoska M Ostojic J Popovic L Vuckovic N 《Neuro endocrinology letters》2007,28(5):560-564
MR spectroscopy (MRS) of hormonally active pituitary adenomas has not been published in literature. We report MR imaging and spectroscopy findings in a 41-year-old man with extrapituitary growth hormone-secreting adenoma. Application of the single voxel proton MRS, SE 135 technique, with voxel size 11x11x11 mm, revealed the elevated choline peak (resonance at 3.2 ppm) in the paramedial aspect of the tumor, while no metabolic activity in the mentioned region was noted using the same method 11 months after Lanreotide treatment. Elevation of choline peak in functional pituitary adenomas could represent an active marker of cellular proliferation, compatible with increased hormonal activity. 相似文献
43.
Jiraskova N Rozsival P Kadlecova J Nekolova J Pozlerova J Dubravska Z 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2007,151(2):311-314
Aims: To compare the metrics and surgical outcome when using Infiniti AquaLase and NeoSoniX cataract removal modalities. Methods: This prospective clinical study involved 50 patients with bilateral cataracts and lens removal using AquaLase in the right eye and NeoSoniX in the left eye. Best corrected visual acuity (BCVA), endothelial cell density and pachymetry were evaluted pre- and postoperatively. Statistical analysis was performed using the Wilcoxon Signed- Rank Test. Results: Preoperative mean pachymetry was 569 +/- 31 mu in the right eye (RE) and 560 +/- 37 mu in the left eye (LE), mean endothelial cell density 2744 +/- 418 cells/mm(2) (RE) and 2730 +/- 472 cells/mm(2) (LE). One week after operation pachymetry was 576 +/- 52 mu (RE) and 583 +/- 72 mu (LE) and endothelial cell density 2388 +/- 586 cells/mm(2) (RE) and 2463 +/- 615 cells/mm(2) (LE). One month after surgery pachymetry was 556 +/- 43 mu (RE) and 559 +/- 44 mu (LE) and endothelial cell density 2368 +/- 52 cells/mm(2) (RE) and 2495 +/- 548 cells/mm(2) (LE). BCVA improved in all eyes and was 0.8 or better on the first postoperative day. Conclusions: Both the NeosoniX and AquaLase minimize intraoperative damage to ocular structures. 相似文献
44.
Disseminated malignancy is responsible for the vast majority of cancer-related deaths. During this process, circulating tumor cells (CTC) are generated, spread from the primary tumor, colonize distant organs and lead to overt metastatic disease. CTC are essential for establishing metastasis; however, they are not sufficient as this process is highly inefficient and most will fail to grow in target sites. Several CTC die during migration while others remain dormant for several years and very few grow into macrometastases. CTC have been well documented in the bloodstream of cancer patients; however, the clinical relevance of this detection is still the subject of controversies and their biology is poorly understood. Indeed, available markers fail to distinguish between subgroups of CTC, and several current methods lack sensitivity, specificity or reproducibility in CTC characterization and detection. The advent of more precise technologies is renewing the interest in CTC biology. We will review herein recent findings on CTC biology, on the role of host-tumor interactions in CTC shedding and implantation, available methods of CTC detection and future perspectives for the molecular characterization of the CTC subset(s) responsible for the development of metastasis. Ultimately, understanding CTC biology and host-tumor 'complementarities' will help define metastasis-related biomarkers providing formidable and tailored novel therapeutic targets. 相似文献
45.
46.
Lauriane Sollelis Mehdi Ghorbal Cameron Ross MacPherson Rafael Miyazawa Martins Nada Kuk Lucien Crobu Patrick Bastien Artur Scherf Jose‐Juan Lopez‐Rubio Yvon Sterkers 《Cellular microbiology》2015,17(10):1405-1412
Protozoan pathogens that cause leishmaniasis in humans are relatively refractory to genetic manipulation. In this work, we implemented the CRISPR‐Cas9 system in Leishmania parasites and demonstrated its efficient use for genome editing. The Cas9 endonuclease was expressed under the control of the Dihydrofolate Reductase‐Thymidylate Synthase (DHFR‐TS) promoter and the single guide RNA was produced under the control of the U6snRNA promoter and terminator. As a proof of concept, we chose to knockout a tandemly repeated gene family, the paraflagellar rod‐2 locus. We were able to obtain null mutants in a single round of transfection. In addition, we confirmed the absence of off‐target editions by whole genome sequencing of two independent clones. Our work demonstrates that CRISPR‐Cas9‐mediated gene knockout represents a major improvement in comparison with existing methods. Beyond gene knockout, this genome editing tool opens avenues for a multitude of functional studies to speed up research on leishmaniasis. 相似文献
47.
Mojca Gorenc Nada Rotovnik Kozjek Primo? Strojan 《Reports of Practical Oncology and Radiotherapy》2015,20(4):249-258
AimTo highlight the problems associated with nutrition that occur in patients with squamous cell carcinoma of the head and neck (SCCHN).BackgroundSCCHN is associated with weight loss before, during and after radiotherapy or concurrent chemoradiotherapy. Because of serious consequences of malnutrition and cachexia on treatment outcome, mortality, morbidity, and quality of life, it is important to identify SCCHN patients with increased risk for the development of malnutrition and cachexia.Materials and methodsCritical review of the literature.ResultsThis review describes pathogenesis, diagnosis and treatment of malnutrition and cancer cachexia. Treatment of malnutrition and cancer cachexia includes nutritional interventions and pharmacological therapy. Advantages and disadvantages of different nutritional interventions and their effect on the nutritional status, quality of life and specific oncological treatment are presented.ConclusionsNutritional management is an essential part of care of these patients, including early screening, assessment of nutritional status and appropriate intervention. 相似文献
48.
49.
Brozovic G Orsolic N Knezevic F Horvat Knezevic A Benkovic V Sakic K Borojevic N Dikic D 《Journal of applied genetics》2011,52(3):355-361
The aim of this study was to evaluate the genotoxicity of repeated exposure to isoflurane or halothane and compare it with
the genotoxicity of repeated exposure to cisplatin. We also determined the genotoxicity of combined treatment with inhalation
anaesthetics and cisplatin on peripheral blood leucocytes (PBL), brain, liver and kidney cells of mice. The mice were divided
into six groups as follows: control, cisplatin, isoflurane, cisplatin–isoflurane, halothane and cisplatin–halothane, and were
exposed respectively for three consecutive days. The mice were treated with cisplatin or exposed to inhalation anaesthetic;
the combined groups were exposed to inhalation anaesthetic after treatment with cisplatin. The alkaline comet assay was performed.
All drugs had a strong genotoxicity (P < 0.05 vs. control group) in all of the observed cells. Isoflurane caused stronger DNA damage on the PBL and kidney cells,
in contrast to halothane, which had stronger genotoxicity on brain and liver cells. The combination of cisplatin and isoflurane
induced lower genotoxicity on PBL than isoflurane alone (P < 0.05). Halothane had the strongest effect on brain cells, but in the combined treatment with cisplatin, the effect decreased
to the level of cisplatin alone. Halothane also induced the strongest DNA damage of the liver cells, while the combination
with cisplatin increased its genotoxicity even more. The genotoxicity of cisplatin and isoflurane on kidney cells were nearly
at the same level, but halothane caused a significantly lower effect. The combinations of inhalation anaesthetics with cisplatin
had stronger effects on kidney cells than inhalation anaesthetics alone. The observed drugs and their combinations induced
strong genotoxicity on all of the mentioned cells. 相似文献
50.
Superimposition of serial Cone Beam Computed Tomography (CBCT) scans has become a valuable tool for three dimensional (3D) assessment of treatment effects and stability. Voxel based image registration is a newly developed semi-automated technique for superimposition and comparison of two CBCT scans. The accuracy and reproducibility of CBCT superimposition on the anterior cranial base or the zygomatic arches using voxel based image registration was tested in this study. 16 pairs of 3D CBCT models were constructed from pre and post treatment CBCT scans of 16 adult dysgnathic patients. Each pair was registered on the anterior cranial base three times and on the left zygomatic arch twice. Following each superimposition, the mean absolute distances between the 2 models were calculated at 4 regions: anterior cranial base, forehead, left and right zygomatic arches. The mean distances between the models ranged from 0.2 to 0.37 mm (SD 0.08-0.16) for the anterior cranial base registration and from 0.2 to 0.45 mm (SD 0.09-0.27) for the zygomatic arch registration. The mean differences between the two registration zones ranged between 0.12 to 0.19 mm at the 4 regions. Voxel based image registration on both zones could be considered as an accurate and a reproducible method for CBCT superimposition. The left zygomatic arch could be used as a stable structure for the superimposition of smaller field of view CBCT scans where the anterior cranial base is not visible. 相似文献