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Andrew Ndegwa Makanya Ivanka Dimova Tobias Koller Beata Styp-Rekowska Valentin Djonov 《PloS one》2016,11(4)
The chick chorioallantoic membrane (CAM) is a widely used model for the study of angiogenesis, tumour growth, as well as drug efficacy. In spite of this, little is known about the developmental alteration from its appearance to the time of hatching. In the current study the CAM has been studied by classical stereology and allometry. Expression levels of selected angiogenesis-related molecules were estimated by RT-PCR and cell dynamics assessed by proliferation and apoptosis assays. Absolute CAM volume increased from a low of 0.47 ± 0.11 cm3 at embryonic day 8 (E8) to a high of 2.05 ± 0.27 cm3 at E18, and then decreased to 1.6 ± 0.47 cm3 at E20. On allometric analysis, three growth phases were identifiable. Between E8-13 (phase I), the CAM grew fastest; moderately in phase II (E13-18) but was regressing in phase III (E18-20). The chorion, the mesenchyme and the allantoic layers grew fastest in phase I, but moderately in phase II. The mesenchyme grew slowly in phase III while the chorion and allantois were regressing. Chorionic cell volume increased fastest in phase I and was regressing in phase III. Chorionic capillaries grew steadily in phase I and II but regressed in phase III. Both the chorion and the allantois grew by intrinsic cell proliferation as well as recruitment of cells from the mesenchyme. Cell proliferation was prominent in the allantois and chorion early during development, declined after E17 and apoptosis started mainly in the chorion from E14. VEGFR2 expression peaked at E11 and declined steadily towards E20, VEGF peaked at E13 and E20 while HIF 1α had a peak at E11 and E20. Studies targeting CAM growth and angiogenesis need to take these growth phases into consideration 相似文献
234.
Krzysztof Owocki Barbara Kremer Beata Wrzosek Agata Królikowska Józef Ka?mierczak 《PloS one》2016,11(2)
Well-preserved mycelia of fungal- or saprolegnia-like biota mineralised by ferromanganese oxides were found for the first time in long bones of Late Cretaceous dinosaurs from the Gobi Desert (Nemegt Valley, Mongolia). The mycelia formed a biofilm on the wall of the bone marrow cavity and penetrated the osteon channels of the nearby bone tissue. Optical microscopy, Raman, SEM/EDS, SEM/BSE, electron microprobe and cathodoluminescence analyses revealed that the mineralisation of the mycelia proceeded in two stages. The first stage was early post-mortem mineralisation of the hyphae by Fe/Mn-oxide coatings and microconcretions. Probably this proceeded in a mildly acidic to circumneutral environment, predominantly due to heterotrophic bacteria degrading the mycelial necromass and liberating Fe and Mn sorbed by the mycelia during its lifetime. The second stage of mineralisation, which proceeded much later following the final burial of the bones in an alkaline environment, resulted from the massive precipitation of calcite and occasionally barite on the iron/manganese-oxide-coated mycelia. The mineral phases produced by fungal biofilms colonising the interiors of decaying dinosaur bones not only enhance the preservation (fossilisation) of fungal remains but can also be used as indicators of the geochemistry of the dinosaur burial sites. 相似文献
235.
Krzysztof Kaliszewski Dorota Diakowska Beata Wojtczak Marta Strutyńska-Karpińska Pawe? Domos?awski Krzysztof Sutkowski Mateusz G?ód Waldemar Balcerzak Zdzis?aw Forkasiewicz Tadeusz ?ukieńczuk 《PloS one》2016,11(1)
Background
Fine-needle aspiration biopsy (FNAB) is a recognized technique for the basic, preoperative cytological diagnosis of thyroid nodules.Aim of the Study
To analyze the accuracy of FNAB in the diagnosis of thyroid cancer in patients with solitary and multiple thyroid nodules and to compare the demographic, clinical and pathological characteristics of patients with thyroid carcinoma in solitary and multiple tumors.Materials and Methods
The case records of 2,403 patients with solitary and multiple thyroid tumors treated consecutively between 2008 and 2013 were analyzed retrospectively. We selected 1,645 for further analysis. A solitary thyroid nodule was observed in 493 patients, and multiple nodules were detected in 1,152 patients. Further classification of the patients in these two groups was performed on the basis of the FNAB results, type of surgery performed and histopathology. TC was histopathologically confirmed in 166 patients, and benign disease was found in 1,479. The TC patients were assigned to the study group, and those with benign thyroid disease were placed into the control group. The study group was divided into two subgroups according to the presence of cancer in a single thyroid nodule or in multiple nodules. Malignancy in a solitary thyroid nodule was diagnosed in 98 (59.0%) patients, and cancer in multiple nodules was diagnosed in 68 (41.0%). Comparative analyses of the demographic, clinical and histopathological characteristics were performed for both subgroups. The following statistical analyses were performed: comparative characteristic of subgroups, ROC analysis for study group and subgroup of patients, and multivariable logistic regression analysis for study group.Results
The rate of prediction of TC by FNAB was three times higher in the patients with a solitary thyroid nodule compared with those with multiple thyroid nodules and it was statistically significant (p<0.001). The rate of total thyroid resection and lack of necessity for reoperation were also significantly higher in the TC patients with a solitary nodule. The histopathological results showed that significantly more patients with a solitary nodule had advanced-stage TC (stage III or IV) and tumor progression (pT3 or pT4) (p = 0.002 for both). ROC analysis demonstrated that the overall accuracy of FNAB as a predictor of thyroid cancer presence was high, especially for the subgroup of patients with a solitary thyroid nodule (AUC = 0.958, p<0.0001). Multivariable logistic regression analysis confirmed that a positive FNAB result was the sole predictor of the performance of total resection in the TC study group (p<0.0001), while a negative FNAB result and the presence of a papillary cancer type were independent predictors of the risk of reoperation (p<0.0001 and p = 0.002, respectively).Conclusions
FNAB often produces false-negative results in patients with multiple malignant thyroid tumors, which results in reoperation in many cases. False-negative FNAB results are rare in patients with a solitary tumor. Because of the low predictive capacity of FNAB for thyroid cancer in patients with multiple thyroid tumors, total thyroid excision should be considered in most cases despite a "negative" (no malignant) FNAB result. 相似文献236.
Beata Jurecka-Lubieniecka Tomasz Bednarczuk Rafal Ploski Jolanta Krajewska Dorota Kula Malgorzata Kowalska Andrzej Tukiendorf Zofia Kolosza Barbara Jarzab 《PloS one》2016,11(3)
Background
Graves’ disease (GD) is a complex disease in which genetic predisposition is modified by environmental factors. Each gene exerts limited effects on the development of autoimmune disease (OR = 1.2–1.5). An epidemiological study revealed that nearly 70% of the risk of developing inherited autoimmunological thyroid diseases (AITD) is the result of gene interactions. In the present study, we analyzed the effects of the interactions of multiple loci on the genetic predisposition to GD. The aim of our analyses was to identify pairs of genes that exhibit a multiplicative interaction effect.Material and Methods
A total of 709 patients with GD were included in the study. The patients were stratified into more homogeneous groups depending on the age at time of GD onset: younger patients less than 30 years of age and older patients greater than 30 years of age. Association analyses were performed for genes that influence the development of GD: HLADRB1, PTPN22, CTLA4 and TSHR. The interactions among polymorphisms were analyzed using the multiple logistic regression and multifactor dimensionality reduction (MDR) methods.Results
GD patients stratified by the age of onset differed in the allele frequencies of the HLADRB1*03 and 1858T polymorphisms of the PTPN22 gene (OR = 1.7, p = 0.003; OR = 1.49, p = 0.01, respectively). We evaluated the genetic interactions of four SNPs in a pairwise fashion with regard to disease risk. The coexistence of HLADRB1 with CTLA4 or HLADRB1 with PTPN22 exhibited interactions on more than additive levels (OR = 3.64, p = 0.002; OR = 4.20, p < 0.001, respectively). These results suggest that interactions between these pairs of genes contribute to the development of GD. MDR analysis confirmed these interactions.Conclusion
In contrast to a single gene effect, we observed that interactions between the HLADRB1/PTPN22 and HLADRB1/CTLA4 genes more closely predicted the risk of GD onset in young patients. 相似文献237.
Recently we demonstrated that human mast cells (MC) express functional TRAIL death receptors. Here we assessed the expression of TRAIL on both mRNA and protein level in cord blood derived MC (CBMC) and HMC-1. The TRAIL release either spontaneous or induced by LPS, IFN-γ and IgE-dependent activation, was evaluated as well. The protein location was restricted to the intracellular compartment in CBMC, but not in HMC-1. The intracellular TRAIL was not localized inside the granules. The treatment with IFN-γ and LPS up-regulated intracellular TRAIL expression in CBMC, but did not induce its release. These in vitro data show that human MC can produce and express intracellular TRAIL whose location could not be altered by different stimuli. 相似文献
238.
Miroslav Sulaj Beata Saniova Eva Drobna Jela Schudichova 《Cellular and molecular neurobiology》2009,29(6-7):807-810
Background Sudden cardiac arrest (CA) is a leading cause of death in Europe. The victims of CA need immediate cardiopulmonary resuscitation (CPR). Patients resuscitated due to CA have high mortality rate. Prognostic evaluation based on clinical observation is uncertain and would benefit from the use of biochemical markers of hypoxic brain damage. Multiple factors of brain origin can be measured in blood. Objective The purpose of this study was to validate the use of the serum neuron-specific enolase (NSE) and malondialdehyde (MDA) concentrations for predicting in-hospital death, after resuscitation from out-of-hospital CA. Neuronal damage and impairment of the blood–brain-barrier integrity can be detected by the release of NSE into cerebrospinal fluid and eventually into the blood. MDA represents a product of lipid peroxide decomposition reactions. Methods In a prospective study of 35 consecutive survivors of out-of-hospital CA, serum samples were obtained within 24, 72 and 168 h after the CA. NSE and MDA concentrations were measured, relationship between concentration in group of in-hospital death and survived patients were examined. Results There was a significant difference in NSE concentration between survivors and dead group on 1st day of measurement, marginally significant difference on 3rd day and no statistically significant difference in NSE on 7th day of measurement. There was marginally significant difference in MDA levels in both groups in all days of measurements. Conclusion Estimation serum concentrations of NSE but not MDA seems to be a predictor of fate of patients after CA. The exact nature of oxidative stress can only be resolved by further studies. 相似文献
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The range of pathologies that lymph node (LN) fine needle cytology (FNC) may encounter is extremely wide and ancillary techniques, in addition to traditional smears, are generally required to reach reliable cytologic diagnoses. Storing part of the cytologic material may be useful or necessary for molecular testing. The main difficulties concern the generally small size of the sample and the different methods of acquisition of LN‐FNC. Therefore, the preanalytic phase is extremely important for LN‐FNC. This article outlines the management of LN‐FNC material, vials, technical devices (e.g.: additional smears, cytospin slides, LBC slides, cards, resins, etc.) and main ancillary techniques to assess their optimal application, taking into account the different diagnostic needs and cell storage. 相似文献