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91.
This paper traces the changes which have occurred in housing provision and management in Poland during the period of transition to the market system. It suggests that the changes that have occurred have been greatly influenced by the environment within which the reforms have taken place. It claims that changes in housing management are restricted by historic attitudes yet have proceeded due to financial constraints imposed as part of the government's policy for restructuring the economy in the early 1990s. At the same time these restrictions have worked against the developmentof the housing market and investment in the existing housing stock. While the planned programmaticand legislative tasks in the reform of Polish housing are concluded, there is still a need for major shifts in the attitudes of consumers and providers to effect these changes.  相似文献   
92.
Cognition, Technology & Work - New technologies are ever evolving and have the power to change human work for the better or the worse depending on the implementation. For human–robot...  相似文献   
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94.
Despite the technological progress of the last decade, dental caries is still the most frequent oral health threat in children and adults alike. Such a condition has multiple triggers and is caused mainly by enamel degradation under the acidic attack of microbial cells, which compose the biofilm of the dental plaque. The biofilm of the dental plaque is a multispecific microbial consortium that periodically develops on mammalian teeth. It can be partially removed through mechanical forces by individual brushing or in specialized oral care facilities. Inhibition of microbial attachment and biofilm formation, as well as methods to strengthen dental enamel to microbial attack, represent the key factors in caries prevention. The purpose of this study was to elaborate a cold plasma-based method in order to modulate microbial attachment and biofilm formation and to improve the retention of fluoride (F) in an enamel-like hydroxyapatite (HAP) model sample. Our results showed improved F retention in the HAP model, which correlated with an increased antimicrobial and antibiofilm effect. The obtained cold plasma with a dual effect exhibited through biofilm modulation and enamel strengthening through fluoridation is intended for dental application, such as preventing and treating dental caries and enamel deterioration.  相似文献   
95.
GABARAP (γ-aminobutyric acid type A receptor-associated protein) and its paralogues GABARAPL1 and GABARAPL2 comprise a subfamily of autophagy-related Atg8 proteins. They are studied extensively regarding their roles during autophagy. Originally, however, especially GABARAPL2 was discovered to be involved in intra-Golgi transport and homotypic fusion of post-mitotic Golgi fragments. Recently, a broader function of mammalian Atg8s on membrane trafficking through interaction with various soluble N-ethylmaleimide-sensitive factor-attachment protein receptors (SNAREs) was suggested. By immunostaining and microscopic analysis of the Golgi network, we demonstrate the importance of the presence of individual GABARAP-type proteins on Golgi morphology. Furthermore, triple knockout (TKO) cells lacking the whole GABARAP subfamily showed impaired Golgi-dependent vesicular trafficking as assessed by imaging of fluorescently labelled ceramide. With the Golgi apparatus being central within the secretory pathway, we sought to investigate the role of the GABARAP-type proteins for cell surface protein trafficking. By analysing the surfaceome composition of TKOs, we identified a subset of cell surface proteins with altered plasma membrane localisation. Taken together, we provide novel insights into an underrated aspect of autophagy-independent functions of the GABARAP subfamily and recommend considering the potential impact of GABARAP subfamily proteins on a plethora of processes during experimental analysis of GABARAP-deficient cells not only in the autophagic context.  相似文献   
96.
Despite substantial research, the understanding of the chemopreventive mechanisms of soy isoflavones remains challenging. Promising tools, such as metabolomics, can provide now a deeper insight into their biochemical mechanisms. The purpose of this study was to offer a comprehensive assessment of the metabolic alterations induced by genistein, daidzein and a soy seed extract on estrogen responsive (MCF-7) and estrogen non-responsive breast cancer cells (MDA-MB-231), using a global metabolomic approach. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that all test compounds induced a biphasic effect on MCF-7 cells and only a dose-dependent inhibitory effect on MDA-MB-231 cells. Proton nuclear magnetic resonance (1H-NMR) profiling of extracellular metabolites and gas chromatography-mass spectrometry (GC-MS) profiling of intracellular metabolites confirmed that all test compounds shared similar metabolic mechanisms. Exposing MCF-7 cells to stimulatory concentrations of isoflavones led to increased intracellular levels of 6-phosphogluconate and ribose 5-phosphate, suggesting a possible upregulation of the pentose phosphate pathway. After exposure to inhibitory doses of isoflavones, a significant decrease in glucose uptake was observed, especially for MCF-7 cells. In MDA-MB-231 cells, the glutamine uptake was significantly restricted, leading to alterations in protein biosynthesis. Understanding the metabolomic alterations of isoflavones represents a step forward in considering soy and soy derivates as functional foods in breast cancer chemoprevention.  相似文献   
97.
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a polyhalogenated planar hydrocarbon belonging to a group of highly toxic and persistent environmental contaminants known as “dioxins”. TCDD is an animal teratogen and carcinogen that is well characterized for causing immunosuppression through activation of aryl hydrocarbon receptor (AHR). In this study, we investigated the effect of exposure of mice to an acute dose of TCDD on the metabolic profile within the serum and cecal contents to better define the effects of TCDD on host physiology. Our findings demonstrated that within the circulating metabolome following acute TCDD exposure, there was significant dysregulation in the metabolism of bioactive lipids, amino acids, and carbohydrates when compared with the vehicle (VEH)-treated mice. These widespread changes in metabolite abundance were identified to regulate host immunity via modulating nuclear factor-kappa B (NF-κB) and extracellular signal-regulated protein kinase (ERK1/2) activity and work as biomarkers for a variety of organ injuries and dysfunctions that follow TCDD exposure. Within the cecal content of mice exposed to TCDD, we were able to detect changes in inflammatory markers that regulate NF-κB, markers of injury-related inflammation, and changes in lysine degradation, nicotinamide metabolism, and butanoate metabolism, which collectively suggested an immediate suppression of broad-scale metabolic processes in the gastrointestinal tract. Collectively, these results demonstrate that acute TCDD exposure results in immediate irregularities in the circulating and intestinal metabolome, which likely contribute to TCDD toxicity and can be used as biomarkers for the early detection of individual exposure.  相似文献   
98.
Photodegradation of the aqueous solutions of acetylsalicylic acid, in the absence (ASA) and the presence of excipients (ASE), is demonstrated by the photoluminescence (PL). A shift of the PL bands from 342 and 338 nm to 358 and 361–397 nm for ASA and ASE in solid state and as aqueous solutions was reported. By exposure of the solution of ASA 0.3 M to UV light, a decrease in the PL band intensity was highlighted. This behavior was revealed for ASA in the presence of phosphate buffer (PB) having the pH equal to 6.4, 7, and 8 or by the interaction with NaOH 0.3 M. A different behavior was reported in the case of ASE. In the presence of PB, an increase in the intensity of the PL band of ASE simultaneously with a change of the ratio between the intensities of the bands at 361–364 and 394–397 nm was highlighted. The differences between PL spectra of ASA and ASE have their origin in the presence of salicylic acid (SAL). The interaction of ASE with NaOH induces a shift of the PL band at 405–407 nm. Arguments for the reaction of ASA with NaOH are shown by Raman scattering and FTIR spectroscopy.  相似文献   
99.
SARS-CoV-2/Coronavirus 2019 (COVID-19) is responsible for the pandemic, which started in December 2019. In addition to the typical respiratory symptoms, this virus also causes other severe complications, including neurological ones. In diagnostics, serological and polymerase chain reaction tests are useful not only in detecting past infections but can also predict the response to vaccination. It is now believed that an immune mechanism rather than direct viral neuroinvasion is responsible for neurological symptoms. For this reason, it is important to assess the presence of antibodies not only in the serum but also in the cerebrospinal fluid (CSF), especially in the case of neuro-COVID. A particular group of patients are people with multiple sclerosis (MS) whose disease-modifying drugs weaken the immune system and lead to an unpredictable serological response to SARS-CoV-2 infection. Based on available data, the article summarizes the current serological information concerning COVID-19 in CSF in patients with severe neurological complications and in those with MS.  相似文献   
100.
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