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1.
Molecules ; 26(21)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34771011

RESUMO

The influence of macromolecular architecture on shear-induced crystallization of poly(L-lactide) (PLLA) was studied. To this aim, three star PLLAs, 6-arm with Mw of 120 and 245 kg/mol, 4-arm with Mw of 123 kg/mol, and three linear PLLAs with Mw of 121, 240 and 339 kg/mol, were synthesized and examined. The PLLAs were sheared at 170 and 150 °C, at 5/s, 10/s and 20/s for 20 s, 10 s and 5 s, respectively, and then cooled at 10 or 30 °C/min. Shear-induced crystallization during cooling was followed by a light depolarization method, whereas the crystallized specimens were examined by DSC, 2D-WAXS, 2D-SAXS and SEM. The effect of shear depended on the shearing conditions, cooling rate and polymer molar mass but it was also affected by the macromolecular architecture. The shear-induced crystallization of linear PLLA with Mw of 240 kg/mol was more intense than that of the 6-arm polymer with similar Mw, most possibly due to its higher Mz. However, the influence of shear on the crystallization of the star polymers with Mw close to 120 kg/mol was stronger than on that of their linear analog. This was reflected in higher crystallization temperature, as well as crystallinity achieved during cooling.

2.
PLoS One ; 16(10): e0258641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34648584

RESUMO

The assessment of the suitability of existing buildings for implementation of green roofs is an important research issue, especially in the context of Urban Heat Island (UHI), the negative impacts of which are locally exacerbated by the global warming. The studies carried out so far have covered a variety of buildings and have taken into account a range of different conditions. Relatively little attention has been paid to the possibilities of greening the roofs of prefabricated apartment blocks from the second half of the 20th century in the context of the potential climate effect. Yet, these buildings are found in many cities around the world, and seem in fact attractive for greening. In view of the above, we proposed a three-stage investigatory procedure to: (I) identify and classify buildings based on the number of floors and the rooftop available area; (II) select buildings by designating priority areas depending on the highest UHI intensity and roof density; (III) analyse the roof load capacity to develop retrofit scenarios. The procedure was applied to prefabricated housing estates built in the 1970s and 1980s in Wroclaw, Poland. The research shows that there are 1962 buildings of different heights and roof area of 722405 m2, of which 480 buildings with a roof area of 122749.1 m2 were selected for greening within priority areas. The structure of the studied roofs was not designed to carry additional loads, which requires the application of complementary solutions. Scenario 1 assumes extensive greening provided that the existing ventilated roof is strengthened, scenario 2 -semi-intensive greening, which however requires the conversion of the ventilated roof to a non-ventilated one. The presented procedure can be applied in any other city with prefabricated apartment blocks and available UHI data, and serve to support the decision to implement green roofs to mitigate UHI.

3.
Int J Mol Sci ; 22(17)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34502425

RESUMO

NKT cells comprise three subsets-type I (invariant, iNKT), type II, and NKT-like cells, of which iNKT cells are the most studied subset. They are capable of rapid cytokine production after the initial stimulus, thus they may be important for polarisation of Th cells. Due to this, they may be an important cell subset in autoimmune diseases. In the current review, we are summarising results of NKT-oriented studies in major neurological autoimmune diseases-multiple sclerosis, myasthenia gravis, and Guillain-Barre syndrome and their corresponding animal models.


Assuntos
Síndrome de Guillain-Barré/imunologia , Células Matadoras Naturais/imunologia , Esclerose Múltipla/imunologia , Miastenia Gravis/imunologia , Células T Matadoras Naturais/imunologia , Animais , Síndrome de Guillain-Barré/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Células Matadoras Naturais/patologia , Esclerose Múltipla/patologia , Miastenia Gravis/patologia , Células T Matadoras Naturais/patologia
4.
J Clin Med ; 10(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34501259

RESUMO

Selective IgA deficiency (sIgAD) is the most common primary immunodeficiency disease (PID), with an estimated occurrence from about 1:3000 to even 1:150, depending on population. sIgAD is diagnosed in adults and children after the 4th year of age, with immunoglobulin A level below 0.07 g/L and normal levels of IgM and IgG. Usually, the disease remains undiagnosed throughout the patient's life, due to its frequent asymptomatic course. If symptomatic, sIgAD is connected to more frequent viral and bacterial infections of upper respiratory, urinary, and gastrointestinal tracts, as well as autoimmune and allergic diseases. Interestingly, it may also be associated with other PIDs, such as IgG subclasses deficiency or specific antibodies deficiency. Rarely sIgAD can evolve to common variable immunodeficiency disease (CVID). It should also be remembered that IgA deficiency may occur in the course of other conditions or result from their treatment. It is hypothesized that allergic diseases (e.g., eczema, rhinitis, asthma) are more common in patients diagnosed with this particular PID. Selective IgA deficiency, although usually mildly symptomatic, can be difficult for clinicians. The aim of the study is to summarize the connection between selective IgA deficiency and atopic diseases.

5.
Cells ; 10(9)2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34571840

RESUMO

Helicobacter pylori (H. pylori) is most known to cause a wide spectrum of gastrointestinal impairments; however, an increasing number of studies indicates that H. pylori infection might be involved in numerous extragastric diseases such as neurological, dermatological, hematologic, ocular, cardiovascular, metabolic, hepatobiliary, or even allergic diseases. In this review, we focused on the nervous system and aimed to summarize the findings regarding H. pylori infection and its involvement in the induction/progression of neurological disorders. Neurological impairments induced by H. pylori infection are primarily due to impairments in the gut-brain axis (GBA) and to an altered gut microbiota facilitated by H. pylori colonization. Currently, regarding a potential relationship between Helicobacter infection and neurological disorders, most of the studies are mainly focused on H. pylori.


Assuntos
Sistema Nervoso Central/microbiologia , Microbioma Gastrointestinal/fisiologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Helicobacter pylori/patogenicidade , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/microbiologia , Animais , Humanos
6.
Int J Mol Sci ; 22(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209289

RESUMO

The continually evolving severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has resulted in a vast number of either acute or chronic medical impairments of a pathophysiology that is not yet fully understood. SARS-CoV-2 tropism for the organs is associated with bilateral organ cross-talks as well as targeted dysfunctions, among which acute kidney injury (AKI) seems to be highly prevalent in infected patients. The need for efficient management of COVID-related AKI patients is an aspect that is still being investigated by nephrologists; however, another reason for concern is a disturbingly high proportion of various types of kidney dysfunctions in patients who have recovered from COVID-19. Even though the clinical picture of AKI and COVID-related AKI seems to be quite similar, it must be considered that regarding the latter, little is known about both the optimal management and long-term consequences. These discrepancies raise an urgent need for further research aimed at evaluating the molecular mechanisms associated with SARS-CoV-2-induced kidney damage as well as standardized management of COVID-related AKI patients. The following review presents a comprehensive and most-recent insight into the pathophysiology, clinical manifestations, recommended patient management, treatment strategies, and post-mortem findings in patients with COVID-related AKI.


Assuntos
Injúria Renal Aguda/diagnóstico , COVID-19/patologia , Injúria Renal Aguda/etiologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Biomarcadores/metabolismo , COVID-19/complicações , COVID-19/tratamento farmacológico , COVID-19/virologia , Taxa de Filtração Glomerular , Humanos , Interleucina-6/metabolismo , Sistema Renina-Angiotensina , Rabdomiólise/etiologia , SARS-CoV-2/isolamento & purificação
7.
J Agric Food Chem ; 69(23): 6444-6454, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34100602

RESUMO

The proteins in the starchy endosperm of wheat determine wheat quality and exhibit a quantitative gradient decreasing from the outer to inner endosperm. Here, we investigate how protein-rich sub-aleurone cells contribute to the protein content and gradient by studying three cultivars, each cultivated at three levels of nitrogen (N)-fertilization. The observed increased protein content with increased N-fertilization was cultivar-dependent. Image analysis showed that the underlying protein gradient could be described by a declining biexponential curve, with protein contents up to 32.0% in the sub-aleurone. Cultivars did not differ in protein content in the center of the cheeks and only differed in the outer endosperm when N-fertilization is applied. N-Fertilization resulted in relatively higher increases in protein content in the outer compared to inner endosperm. Hence, sub-aleurone cells could affect the classification of cultivars by baking quality. Cultivar selection and N-fertilization could furthermore be promising techniques to produce protein-rich miller's bran.


Assuntos
Endosperma , Triticum , Endosperma/genética , Fertilização , Proteínas de Plantas/genética
8.
Materials (Basel) ; 13(22)2020 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-33202639

RESUMO

Reversible deactivation radical polymerizations with reduced amount of organometallic catalyst are currently a field of interest of many applications. One of the very promising techniques is photoinduced atom transfer radical polymerization (photo-ATRP) that is mainly studied for copper catalysts in the solution. Recently, advantageous iron-catalyzed photo-ATRP (photo-Fe-ATRP) compatible with high demanding biological applications was presented. In response to that, we developed surface-initiated photo-Fe-ATRP (SI-photo-Fe-ATRP) that was used for facile synthesis of poly(methyl methacrylate) brushes with the presence of only 200 ppm of FeBr3/tetrabutylammonium bromide catalyst (FeBr3/TBABr) under visible light irradiation (wavelength: 450 nm). The kinetics of both SI-photo-Fe-ATRP and photo-Fe-ATRP in solution were compared and followed by 1H NMR, atomic force microscopy (AFM) and gel permeation chromatography (GPC). Brush grafting densities were determined using two methodologies. The influence of the sacrificial initiator on the kinetics of brush growth was studied. It was found that SI-photo-Fe-ATRP could be effectively controlled even without any sacrificial initiators thanks to in situ production of ATRP initiator in solution as a result of reaction between the monomer and Br radicals generated in photoreduction of FeBr3/TBABr. The optimized and simplified reaction setup allowed synthesis of very thick (up to 110 nm) PMMA brushes at room temperature, under visible light with only 200 ppm of iron-based catalyst. The same reaction conditions, but with the presence of sacrificial initiator, enabled formation of much thinner layers (18 nm).

9.
J Exp Bot ; 69(12): 3117-3126, 2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29660003

RESUMO

Gradients exist in the distribution of storage proteins in the wheat (Triticum aestivum) endosperm and determine the milling properties and protein recovery rate of the grain. A novel image analysis technique was developed to quantify both the gradients in protein concentration, and the size distribution of protein bodies within the endosperm of wheat plants grown under two different (20 or 28 °C) post-anthesis temperatures, and supplied with a nutrient solution with either high or low nitrogen content. Under all treatment combinations, protein concentration was greater in the endosperm cells closest to the aleurone layer and decreased towards the centre of the two lobes of the grain, i.e. a negative gradient. This was accompanied by a decrease in size of protein bodies from the outer to the inner endosperm layers in all but one of the treatments. Elevated post-anthesis temperature had the effect of increasing the magnitude of the negative gradients in both protein concentration and protein body size, whilst limiting nitrogen supply decreased the gradients.


Assuntos
Endosperma/fisiologia , Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Temperatura , Triticum/fisiologia , Ensaios de Triagem em Larga Escala
10.
Colloids Surf B Biointerfaces ; 159: 820-828, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28888199

RESUMO

Here we report the first of the phenosafranin-chlorambucil conjugate as a new type of a chemotherapeutic agent suitable for dual detection methods (spectrophotometric and fluorescence) in imaging systems and cancer treatment. The synthetic cationic dye (3,7-diamino-5-phenylphenazinium chloride) is used as a fluorescent light-triggered scaffold that acts as a carrier for an anti-cancer drug. The chlorambucil was attached covalently via amide bonds to the bifunctional fluorophore, which facilitates tracking with visible light. Our studies revealed that the new photosensitive compound exhibits improved intrinsic activity in vitro in HeLa cells culture experiments; thus it could be a potential anti-cancer candidate in theranostic drug-delivery systems. In light of the urgent need for in vivo monitoring of the biodistribution of anti-cancer drugs, this strategy for the synthesis of innovative conjugates based on the phenosafranin backbone offers a promising possibility for drug control in anti-cancer therapy and diagnosis. This aspect makes the phenosafranin-chlorambucil conjugate unique among currently available biomarkers.


Assuntos
Antineoplásicos/química , Clorambucila/química , Fenazinas/química , Sistemas de Liberação de Medicamentos/métodos , Células HeLa , Humanos
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