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51.
Ewa Sobolewska Piotr Makowiecki Justyna Drozdowska Ireneusz Dziuba Alicja Nowicka Marzena Wyganowska-
witkowska Joanna Janiszewska-Olszowska Katarzyna Grocholewicz 《Materials》2022,15(4)
(1) In recent years, there has been a significant increase in the availability of denture adhesives for stabilizing removable dentures. The aim of the present study was to assess the cytotoxicity of three denture adhesives on human fibroblasts. (2) Methods: Three denture adhesives were analyzed. Fibroblast cultures were established for the study and control groups in order to assess the incidence of necrosis and to evaluate the microscopic intracellular alterations induced. Following incubation with (study groups) or without adhesives (control group), trypan blue dye exclusion assay was used to determine the number of viable and/or dead cells. Microscopic specimens were stained with haematoxylin and eosin, scanned, digitally processed and then analyzed by a histopathologist. (3) Results: All three denture adhesives analyzed demonstrated various toxic effects in vitro on human fibroblast: quantitative evaluation—45.87–61.13% reduction of cell viability (p = 0.0001) and slight to moderate cytotoxicity in qualitative evaluation. (4) Conclusions: Denture adhesive creams demonstrated a toxic effect on human fibroblasts in vitro in quantitative and qualitative evaluation. In vivo observations are needed to find out if denture adhesives present a cytotoxic effect in patients. 相似文献
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This paper analyses the interference of three socio-demographic characteristics: gender, age and migration status on the labour market outcomes from the perspective of intersectionality theory. Concretely, we investigate whether gender and migration differences in hourly wages are observable at younger ages and whether these differences increase with age. Further, we analyse whether gender and migration interact in such a way that women with migration background suffer lower wage growth in relation to their counterparts. Our analyses draw on data from the Socio-Economic Panel (German SOEP from 1991 to 2014), distinguishing between populations with and without a migration background. Random effects hourly wage regressions controlling for selection bias using Heckman procedure have been estimated in our analysis. The results show that there are large gender differences in hourly wage at younger ages, and these differences are maintained over the life course. Regarding migration status, no significant disadvantages in wages are observable at early stages. However, disadvantages of men and women with migration background increase with age, resulting in lower earnings for older workers with migration background. When we analyse the interaction between migration and gender, we observe no effect either at younger ages or over the entire lifespan, indicating that the gender disadvantage is no more pronounced for women with migration background than for women without such a background (and vice versa). 相似文献
56.
The uterus is an essential organ for reproduction in mammals that derives from the Müllerian duct. Despite the importance of the uterus for the fertility and health of women and their offspring, relatively little is known about the hormonal, cellular and molecular mechanisms that regulate development of the Müllerian duct and uterus. This review aims to summarize the hormonal, cellular and molecular mechanisms and pathways governing development of the Müllerian duct and uterus as well as highlight developmental programming effects of endocrine disruptor compounds. Organogenesis, morphogenesis, and functional differentiation of the uterus are complex, multifactorial processes. Disruption of uterine development in the fetus and neonate by genetic defects and exposure to endocrine disruptor compounds can cause infertility and cancer in the adult and their offspring via developmental programming. Clear conservation of some factors and pathways are observed between species; therefore, comparative biology is useful to identify candidate genes and pathways underlying congenital abnormalities in humans. 相似文献
57.
Justyna A. Karolak Przemyslaw Szafranski David Kilner Chirag Patel Bonnie Scurry Esther Kinning Kate Chandler Shalini N. Jhangiani Zeynep H. Coban Akdemir James R. Lupski Edwina Popek Paweł Stankiewicz 《Clinical genetics》2019,96(4):366-370
The canonical wingless (Wnt) and fibroblast growth factor (FGF) signaling pathways involving CTNNB1 and TBX4, respectively, are crucial for the regulation of human development. Perturbations of these pathways and disruptions from biological homeostasis have been associated with abnormal morphogenesis of multiple organs, including the lung. The aim of this study was to identify the underlying genetic cause of abnormal lung growth, pulmonary hypertension (PAH), severe microcephaly, and muscle spasticity in a full-term newborn, who died at 4 months of age due to progressively worsening PAH and respiratory failure. Family trio exome sequencing showed a de novo heterozygous nonsense c.1603C>T (p.Arg535*) variant in CTNNB1 and a paternally inherited heterozygous missense c.1198G>A (p.Glu400Lys) variant in TBX4, both predicted to be likely deleterious. We expand the phenotypic spectrum associated with CTNNB1 and TBX4 variants and indicate that they could act synergistically to produce a distinct more severe phenotype. Our findings further support a recently proposed complex compound inheritance model in lethal lung developmental diseases and the contention that dual molecular diagnoses can parsimoniously explain blended phenotypes. 相似文献
58.
Ivan Pavlenko Milan Saga Ivan Kuric Alexey Kotliar Yevheniia Basova Justyna Trojanowska Vitalii Ivanov 《Materials》2020,13(23)
The intensifying of the manufacturing process and increasing the efficiency of production planning of precise and non-rigid parts, mainly crankshafts, are the first-priority task in modern manufacturing. The use of various methods for controlling the cutting force under cylindrical infeed grinding and studying its impact on crankpin machining quality and accuracy can improve machining efficiency. The paper deals with developing a comprehensive scientific and methodological approach for determining the experimental dependence parameters’ quantitative values for cutting-force calculation in cylindrical infeed grinding. The main stages of creating a method for conducting a virtual experiment to determine the cutting force depending on the array of defining parameters obtained from experimental studies are outlined. It will make it possible to get recommendations for the formation of a valid route for crankpin machining. The research’s scientific novelty lies in the developed scientific and methodological approach for determining the cutting force, based on the integrated application of an artificial neural network (ANN) and multi-parametric quasi-linear regression analysis. In particular, on production conditions, the proposed method allows the rapid and accurate assessment of the technological parameters’ influence on the power characteristics for the cutting process. A numerical experiment was conducted to study the cutting force and evaluate its value’s primary indicators based on the proposed method. The study’s practical value lies in studying how to improve the grinding performance of the main bearing and connecting rod journals by intensifying cutting modes and optimizing the structure of machining cycles. 相似文献
59.
BACKGROUND/AIMS: The purpose of this study was to evaluate the clinicopathologic characteristics, diagnosis and treatment of mucinous cystadenocarcinomas (MCACs) of the pancreas. METHODOLOGY: This is a retrospective review of 6 patients who underwent curative resection for MCACs of the pancreas in the Department of General Endocrine and Transplantation Surgery, Medical University of Gdańsk from 1994-2004. Clinical presentation, radiological evaluation and surgical procedures were analyzed. RESULTS: There were 4 women and 2 men. Median age was 59 years. Patients complained of abdominal pain, nausea, vomiting and weigh loss, 2 of them had jaundice and 1 gastrointestinal (GI) bleeding. Ultrasonography and computed tomography showed cystic lesions. Solid component was found in 3 cases. Three endoscopic retrograde cholangiopancreatographys (ERCPs) were unhelpful in differentiating between malignant tumor and benign lesion. All patients underwent resection. In 3 cases Whipple resection, in 1 case Traverso - Longmire resection and in 2 cases distal pancreatectomy was performed. Histopathologically, all tumors were mucinous cystadenocarcinomas. CONCLUSIONS: Diagnostic accuracy for cystic pancreatic neoplasm is still limited. Surgical resection is recommended in all cystic tumors that are not clearly defined. 相似文献
60.
Justyna Zygmuntowicz Radosaw urowski Justyna Tomaszewska Marcin Wachowski Janusz Torzewski Paulina Piotrkiewicz Micha Gloc Katarzyna Konopka 《Materials》2021,14(9)
The present work deals with the evaluation of the effect of ZrO2 on the structure and selected properties of shapes obtained using the centrifugal slip casting method. The samples were made of alumina and zirconia. The applied technology made it possible to produce tubes with a high density reaching 99–100% after sintering. Very good bonding was obtained at the Al2O3/ZrO2 interphase boundaries with no discernible delamination or cracks, which was confirmed by STEM observations. In the case of Al2O3/ZrO2 composites containing 5 vol.% and 10 vol.% ZrO2, the presence of equiaxial ZrO2 grains with an average size of 0.25 µm was observed, which are distributed along the grain boundaries of Al2O3. At the same time, the composites exhibited a very high hardness of 22–23 GPa. Moreover, the environmental influences accompanying the sintering process were quantified. The impacts were determined using the life cycle analysis method, in the phase related to the extraction and processing of raw materials and the process of producing Al2O3/ZrO2 composites. The results obtained show that the production of 1 kg of sintered composite results in greenhouse gas emissions of 2.24–2.9 kg CO2 eq. which is comparable to the amount of emissions accompanying the production of 1 kg of Polyvinyl Chloride (PVC), Polypropylene (PP), or hot-rolled steel products. 相似文献