transport potential
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Author(s):  
А.В. Муравьев ◽  
П.В. Михайлов ◽  
В.В. Зинчук ◽  
И.А. Тихомирова ◽  
Р.С. Остроумов

Введение. Доставка кислорода в ткани определяется величиной объемного кровотока; он, в свою очередь, зависит от сосудистых и реологических факторов. Снижение вязкости крови (ВК) может способствовать приросту объемного кровотока и повышению эффективности доставки кислорода. Поскольку ВК тесно связана с микрореологическими свойствами эритроцитов, то можно полагать, что их положительные изменения будут способствовать улучшению кислородтранспортной функции крови. Цель исследования: сравнительный анализ гемореологических профилей у лиц с разным уровнем обеспечения организма кислородом и определение роли оксида азота (NO) и сульфида водорода (H2S) в изменениях микрореологических характеристик эритроцитов. Материалы и методы. На основе результатов определения максимального потребления кислорода (МПК) были сформированы 2 группы, в каждой из которых было по 24 практически здоровых мужчины-добровольца в возрасте от 20 до 35 лет: группа 1 – лица с умеренным обеспечением организма кислородом (МПК = 40–50 мл/кг/мин) и группа 2 – лица с относительно высоким его уровнем (МПК = 51–65 мл/кг/мин). Регистрировали параметры гемореологического профиля, напряжение кислорода в коже предплечья (tсрО2), метаболизм оксида азота (по соотношению нитраты/нитриты, NOx). Для исследования влияния газотрансмиттеров (ГТ) на микрореологию эритроцитов их инкубировали с донором NO (нитропруссидом натрия, 100 мкмоль) и донором H2S (гидросульфидом натрия, 100 мкмоль) с последующей регистрацией деформируемости и агрегации эритроцитов. Результаты. У лиц с относительно высоким обеспечением тканей кислородом отмечалась сниженная вязкость крови, ее высокий кислородтранспортный потенциал, эффективная микрореология эритроцитов и их более высокая чувствительность к ГТ при положительном влиянии последних на агрегацию и деформируемость эритроцитов. Заключение. Данные, полученные на моделях микрореологических ответов эритроцитов на доноры двух газотрансмиттеров, позволяют заключить, что, во-первых, эти ГТ, как сигнальные молекулы, положительно влияют на микрореологические характеристики эритроцитов и, следовательно, на их транспортный потенциал, и, во-вторых, эритроциты лиц, имеющих высокий уровень обеспечения организма кислородом, более чувствительны к регуляторному действию газотрансмиттеров, поскольку их микрореологические ответы на доноры были статистически значимо более выраженными. Background. Oxygen delivery to tissues is determined by the volume of blood flow that, in turn, depends on vascular and rheological factors. Blood viscosity (BV) decreasing can promote an increasing of volumetric blood flow and provide more efficient oxygen transport. Since BV depends on the erythrocyte microrheological properties it can be assumed that their positive changes will contribute to better oxygen transport. Objectives: to investigate hemorheological profiles in individuals with different levels of body oxygen supply and the role of nitrogen oxide (NO) and hydrogen sulfide (H2S) in changes of the erythrocyte microrheological characteristics. Patients/Methods. Based on the determination of maximum oxygen consumption (VO2max), 2 groups were formed, each of which consisted of 24 practically healthy male volunteers aged 20–35 years: group 1 – persons with moderate body oxygen supply (VO2max = 40–50 ml/kg/min) and group 2 – persons with a relatively high body oxygen supply (VO2max = 51–65 ml/kg/min). Hemorheological profi le parameters, oxygen tension in the forearm skin (tcpO2), and nitric oxide metabolism by the ratio of nitrates/nitrites (NOx) were recorded. To study the effect of gasotransmitters (GTs) on erythrocyte microrheology, they were incubated with NO donor (sodium nitroprusside, 100 μmol) and H2S donor (sodium hydrosulfide, 100 μmol), and erythrocytes deformability and aggregation were registered. Results. Individuals with a relatively high oxygen supply of tissues showed a reduced blood viscosity, high blood oxygen transport potential, an effective microrheology of erythrocytes and their higher sensitivity to GTs with their positive effect on erythrocytes aggregation and deformability. Conclusions. The obtained data on models of erythrocyte microrheological responses to donors of two gasotransmitters allow us to conclude that, firstly, these GTs, as signaling molecules, have a positive effect on the erythrocyte microrheological characteristics and, consequently, on their transport potential, and, secondly, erythrocytes from individuals with a high level of oxygen body supply are more sensitive to the regulatory action of GTs, because their microrheological responses to donors were statistically significantly more expressed.


Nanomedicine ◽  
2021 ◽  
Author(s):  
Samar A Rizk ◽  
Manal A Elsheikh ◽  
Yosra S R Elnaggar ◽  
Ossama Y Abdallah

Aim: The aim of this study was to elaborate on ‘bioemulsomes,' novel biocompatible lipoprotein analogs for effective lymphatic transport of baicalin (BCL). Methods: BCL bioemulsomes were developed and optimized and in vitro physicochemical characterization performed. The bioavailability of BCL bioemulsomes compared with free BCL was investigated using in vivo pharmacokinetics studies. Finally, BCL lymphatic transport was assessed via cycloheximide blockade assay. Results: Optimized BCL-loaded nanoemulsomes showed promising in vitro characteristics that favor lymphatic targeting. In vivo pharmacokinetics showed a significant improvement in bioavailability over free BCL. A significant decrease in BCL emulsome absorption (33%) was exhibited after chemical blockage of the lymphatic pathway, confirming the lymphatic transport potential. Conclusion: Bioemulsomes could be a promising tool for bypassing BCL oral delivery hurdles as well as lymphatic transport, paving the way for potential treatment of lymphoma.


2021 ◽  
Vol 16 (02) ◽  
pp. 42-57
Author(s):  
Giorgi Abashishvili Giorgi Abashishvili

The recent years witnessed the repeated urgency of Georgia's transport potential. In parallel, Georgia's role in the BRI initiative has become clear. Consequently, Georgia's capabilities have become clearer, however, there are still issues in this regard, the study of which will greatly help the country to achieve SDGs and increase efficiency. To achieve the above objective, complex recommendations have been developed within the scope of the survey that will significantly increase the country's transport potential and attractiveness; however, it should also be noted that the impact of the transit corridor on the achievement of the Sustainable Development Goals (SDGs) to promote inclusive economic development/growth in the long-term perspective should be considered. The survey is dedicated to the analysis of Georgia's transit potential, opportunities, existing problems, challenges and prospects, as well as recommendations for the use of this potential to achieve the country's Sustainable Development Goals (SDGs), which analyzes the country's top priorities, current risks and economic development opportunities. Keywords: Transit potential


2021 ◽  
Author(s):  
Philipp Resl ◽  
Adina R. Bujold ◽  
Gulnara Tagirdzhanova ◽  
Peter Meidl ◽  
Sandra Freire Rallo ◽  
...  

Lichen symbioses are generally thought to be stabilized by the transfer of fixed carbon compounds from a photosynthesizing unicellular symbiont to a fungus. In other fungal symbioses, carbohydrate subsidies correlate with genomic reductions in the number of genes for plant cell wall-degrading enzymes (PCWDEs), but whether this is the case with lichen fungal symbionts (LFSs) is unknown. We predicted genes encoding carbohydrate-active enzymes (CAZymes) and sugar transporters in 17 existing and 29 newly sequenced genomes from across the class Lecanoromycetes, the largest extant clade of LFSs. Despite possessing lower mean numbers of PCWDE genes compared to non-symbiont Ascomycota, all LFS genomes possessed a robust suite of predicted PCWDEs. The largest CAZyme gene numbers, on par with model species such as Penicillium, were retained in genomes from the subclass Ostropomycetidae, which are found in crust lichens with highly specific ecologies. The lowest numbers were in the subclass Lecanoromycetidae, which are symbionts of many generalist macrolichens. Our results suggest that association with phototroph symbionts does not in itself result in functional loss of PCWDEs and that PCWDE losses may have been driven by adaptive processes within the evolution of specific LFS lineages. The inferred capability of some LFSs to access a wide range of carbohydrates suggests that some lichen symbioses may augment fixed CO2 with carbon from external sources.


2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Helena Andrade ◽  
Juliane Glüge ◽  
Dorte Herzke ◽  
Narain Maharaj Ashta ◽  
Shwetha Manohar Nayagar ◽  
...  

AbstractMost plastics are made of persistent synthetic polymer matrices that contain chemical additives in significant amounts. Millions of tonnes of plastics are produced every year and a significant amount of this plastic enters the marine environment, either as macro- or microplastics. In this article, an overview is given of the presence of marine plastic debris globally and its potential to reach remote locations in combination with an analysis of the oceanic long-range transport potential of organic additives present in plastic debris. The information gathered shows that leaching of hydrophobic substances from plastic is slow in the ocean, whereas more polar substances leach faster but mostly from the surface layers of the particle. Their high content used in plastic of several percent by weight allows also these chemicals to be transported over long distances without being completely depleted along the way. It is therefore likely that various types of additives reach remote locations with plastic debris. As a consequence, birds or other wildlife that ingest plastic debris are exposed to these substances, as leaching is accelerated in warm-blooded organisms and in hydrophobic fluids such as stomach oil, compared to leaching in water. Our estimates show that approximately 8′100–18′900 t of various organic additives are transported with buoyant plastic matrices globally with a significant portion also transported to the Arctic. For many of these chemicals, long-range transport (LRT) by plastic as a carrier is their only means of travelling over long distances without degrading, resulting in plastic debris enabling the LRT of chemicals which otherwise would not reach polar environments with unknown consequences. The transport of organic additives via plastic debris is an additional long-range transport route that should also be considered under the Stockholm Convention.


2021 ◽  
Vol 23 (2(79)) ◽  
pp. 105-111
Author(s):  
K. KUZMENKO

Topicality. The shipping policy macroeconomic level takes the central place in the management system of merchant shipping and investment activity according to the development efficiency criteria. The economy is characterized by the building-up of integration processes at the current stage. Increasing production internationalization and globalization leads to the internationalization and globalization of transport and logistics systems and distribution networks. These processes activate the intensity and increase the international freight traffic volume. At the same time, globalization has dramatically changed the volume and model of freight traffic and increased the requirements for both international and local transport systems. Aim and tasks. The central task of the investigations is the choice of a criteria-based assessment system of economic and investment decisions. The study is aimed at clarifying the regularities of the merchant shipping individual segments functioning and at developing recommendations for solving urgent current and future projects for the national shipping potential development. Research results. The transport system efficiency is the economy development important factor. The main transport potential feature is the need of high level of regulation by country. This is due to the fact that: the development of transit potential is a capital-intensive process, and requires long-term investments; it has the monopolistic nature of the elements of the transport system; it needs for a special functional and legal regime of work; it is the reason of environmental problems because of increasing volumes and traffic intensity; it is especially important for national security. Macroeconomic goals to ensure the export transport services development, to use transit potential more efficiently, to increase the consumer transport competitiveness on the transport services international market could be actualized by the integration technology strategy implementation. Conclusion. The implementation of transport potential according to the integration criteria is an important factor of the modern economic development of the country, as, first of all, it is growth of employment, business activity, investments and tax revenues, on the other hand, it assists in integrating the Ukrainian economy into the European and world economic systems. The making economic decisions theory in the maritime transport system in the shipping market globalization context should be taken into account during the urgent economic problems solution.


2021 ◽  
Vol 11 (1) ◽  
pp. 1-19
Author(s):  
sasan zangenehtabar ◽  
◽  
mehran maghsoudi ◽  
fatemeh menbari ◽  
mina hoseini ◽  
...  

2021 ◽  
Author(s):  
Helena Andrade ◽  
Juliane Glüge ◽  
Dorte Herzke ◽  
Ashta Narain ◽  
Shwetha Manohar Nayagar ◽  
...  

Plastics are persistent synthetic matrices that contain chemical additives in significant amounts. Millions of tonnes of plastics are produced every year and a significant amount of this plastic enters the marine environment, either as macro- or microplastics. In this article, an overview is given of the presence of marine plastic debris globally and its potential to reach remote locationsin combination with an analysis of the oceanic long-range transport potential of organic additives present in plastic debris. The information gathered shows that leaching of very hydrophobic substances from plastic is slow in the ocean, whereas more polar substances leach faster but mostly from the surface layers of the particle. Their high content used in plastic of several percent by weight allows also these chemicals to be transported over long distances without being completely depleted along the way. It is therefore likely that various types of additives reach remote locations with plastic debris. As a consequence, birds or other wildlife that ingest plastic debris are exposed to these substances, as leaching is accelerated in warm‐blooded organisms and under acidic stomach conditions compared to leaching in water. Our estimates show that approximately 13’500 t of numerous organic additives are transported within buoyant plastic matrices globallywith a significant portion also transported to the Arctic. For many of these chemicals, LRT by plastic as a carrier is their only means of travelling over long distances without degrading, resulting in plastic debris enabling the LRT of chemicals which otherwise would not reach polar environments with unknown consequences. The transport of organic additives via plastic debris is an additional long‐range transport route that should also be acknowledged under the Stockholm Convention.


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