131 research outputs found
Research Notes : Inheritance of hardseededness in soybean
Soybean is often characterized by hardseededness or seed impermeability, when the seeds do not imbibe water and they germinate very slowly. Germination period of such seeds is very prolonged for a month or more. Hardseededness is caused by reduced water permeability of seed coat. We meet this character in many plant species, but more often in Leguminosae, Rosaceae, Lilium (Chorniy, 1980)
Cost-effectiveness of extended-release niacin/laropiprant added to a stable simvastatin dose in secondary prevention patients not at cholesterol goal in Germany
Coronary heart disease (CHD) remains the leading cause of death in Germany despite statin use to reduce low-density lipoprotein cholesterol (LDL-C) levels; improving lipids beyond LDL-C may further reduce cardiovascular risk. A fixed-dose combination of extended-release niacin (ERN) with laropiprant (LRPT) provides comprehensive lipid management. We adapted a decision-analytic model to evaluate the economic value (incremental cost-effectiveness ratio [ICER] in terms of costs per life-years gained [LYG]) of ERN/LRPT 2 g over a lifetime in secondary prevention patients in a German setting. Two scenarios were modelled: (1) ERN/LRPT 2 g added to simvastatin 40 mg in patients not at LDL-C goal with simvastatin 40 mg; (2) adding ERN/LRPT 2 g compared with titration to simvastatin 40 mg in patients not at LDL-C goal with simvastatin 20 mg. In both scenarios, adding ERN/LRPT was cost-effective relative to simvastatin monotherapy at a commonly accepted threshold of €30,000 per LYG; ICERs for ERN/LRPT were €13,331 per LYG in scenario 1 and €17,684 per LYG in scenario 2. Subgroup analyses showed that ERN/LRPT was cost-effective in patients with or without diabetes, patients aged ≤65 or >65 years and patients with low baseline high-density lipoprotein cholesterol levels; ICERs ranged from €10,342 to €15,579 in scenario 1, and from €14,081 to €20,462 in scenario 2. In conclusion, comprehensive lipid management with ERN/LRPT 2 g is cost-effective in secondary prevention patients in Germany who have not achieved LDL-C goal with simvastatin monotherapy
Costs of treating cardiovascular events in Germany: A systematic literature review
Objective: This study aims to systematically evaluate available evidence regarding direct medical costs of treating cardiovascular (CV) events in Germany after 2003 on an individual patient basis and from a payer perspective. The CV events of interest were myocardial infarction (MI), unstable angina, heart failure (HF), stroke, and peripheral artery disease (PAD). Method: A systematic literature search was performed in the following databases according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines - Medline, Embase, Centre for Reviews and Dissemination, TIBORDER, and German dissertation database from January 2003 to October 2013. Both observational studies and randomized clinical trials were considered for the review. All values stated in € are inflation adjusted to 2014 € unless stated otherwise. Result: This review included 13 articles. For newly occurred MI patients, the average hospitalization costs during the acute phase were reported to be between € 6790 and € 8918 per admission. In the first year after a MI event, direct medical costs were € 13,838-14,792 per patient. Direct medical costs of chronic HF patients were found to be between € 3417 and 5576 per patient per year. Treatment costs increase with disease progression. The average treatment costs for hospitalized PAD in the acute phase were reported to be € 4963 per admission, € 2535 per patient during month 1-6 after the initial hospitalization, € 1601 in month 7-12, and € 1390 in month 13-18. For stroke of all types, total direct medical costs in the 1st year after an event were reported to be € 13,273 per patient. Total direct medical costs during the 1st year after an ischemic stroke event were € 17,399-21,954 per patient, € 6260 in month 13-18, and € 6496 per year in the subsequent 4 years. Conclusion: MI, unstable angina, HF, stroke and PAD have a high financial impact on the German health care system. Treatment costs of these diseases are mostly incurred during the acute phase of events and tend to decrease over time. Hospitalization and rehabilitation costs were two major cost drivers. Medication costs was one of the smallest cost component reported
DNA Interaction with a Polyelectrolyte Monolayer at Solution—Air Interface
The formation of ordered 2D nanostructures of double stranded DNA molecules at various interfaces attracts more and more focus in medical and engineering research, but the underlying intermolecular interactions still require elucidation. Recently, it has been revealed that mixtures of DNA with a series of hydrophobic cationic polyelectrolytes including poly(N,N-diallyl-N-hexyl-N-methylammonium) chloride (PDAHMAC) form a network of ribbonlike or threadlike aggregates at the solution—air interface. In the present work, we adopt a novel approach to confine the same polyelectrolyte at the solution—air interface by spreading it on a subphase with elevated ionic strength. A suite of techniques–rheology, microscopy, ellipsometry, and spectroscopy–are applied to gain insight into main steps of the adsorption layer formation, which results in non-monotonic kinetic dependencies of various surface properties. A long induction period of the kinetic dependencies after DNA is exposed to the surface film results only if the initial surface pressure corresponds to a quasiplateau region of the compression isotherm of a PDAHMAC monolayer. Despite the different aggregation mechanisms, the micromorphology of the mixed PDAHMAC/DNA does not depend noticeably on the initial surface pressure. The results provide new perspective on nanostructure formation involving nucleic acids building blocks
High salt diet impairs cerebral blood flow regulation via salt‐induced angiotensin II suppression
ObjectivesThis study sought to determine whether salt‐induced ANG II suppression contributes to impaired CBF autoregulation.MethodsCerebral autoregulation was evaluated with LDF during graded reductions of blood pressure. Autoregulatory responses in rats fed HS (4% NaCl) diet vs LS (0.4% NaCl) diet were analyzed using linear regression analysis, model‐free analysis, and a mechanistic theoretical model of blood flow through cerebral arterioles.ResultsAutoregulation was intact in LS‐fed animals as MAP was reduced via graded hemorrhage to approximately 50 mm Hg. Short‐term (3 days) and chronic (4 weeks) HS diet impaired CBF autoregulation, as evidenced by progressive reductions of laser Doppler flux with arterial pressure reduction. Chronic low dose ANG II infusion (5 mg/kg/min, i.v.) restored CBF autoregulation between the pre‐hemorrhage MAP and 50 mm Hg in rats fed short‐term HS diet. Mechanistic‐based model analysis showed a reduced myogenic response and reduced baseline VSM tone with short‐term HS diet, which was restored by ANG II infusion.ConclusionsShort‐term and chronic HS diet lead to impaired autoregulation in the cerebral circulation, with salt‐induced ANG II suppression as a major factor in the initiation of impaired CBF regulation.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149286/1/micc12518_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149286/2/micc12518.pd
МОДЕЛЬ СЦЕНАРИЯ ИНТРОДУКЦИИ МОЛОДИ РЫБ С УЧЕТОМ ДИНАМИКИ БИОГЕННЫХ ЭЛЕМЕНТОВ
The article discusses the expansion of the previously formulated approach to modeling aspects of the reproductive cycle, taking into account the changes in the habitat and metamorphosis in the development of fish. Excessive accumulation of nutrients with prolonged use of a reservoir for artificial growth of juveniles or accelerated decomposition of organic nitrogen and phosphorus may in some cases affect the success of the reproductive process. This creates an indirect effect on long-term trends in population dynamics. In some cases, the increase in the influx of organic phosphorus further leads to a state of eutrophication and may affect the insufficient aeration of breeding sites, leading to hypoxia for hatched larvae. Even worsen the situation with the consumption of oxygen in the water at the mass destruction of eggs. Lack of organic matter leads to insufficient development of planktonic organisms for optimal growth of fishes. The system of survivability equations for calculation competing individuals of the generation is supplemented by a functional extension using an iterative model of biogenic elements dynamics, based on the analysis of processes in the ecosystem of Lake Chao. The block of the model for calculating the inflow and destruction of organic matter is synchronized with a continuous-discrete computational structure that takes into account the interrelated changes in mortality factors and the rate of development of juvenile fish during transitions between generalized ecological and physiological stages of development.Рассматривается расширение ранее сформулированного подхода к моделированию аспектов репродуктивного цикла с учетом происходящих перемен в среде обитания и метаморфозов в развитии рыб. Избыточное накопление биогенных элементов при длительном использовании водоемов для искусственного выращивания молоди или ускоренный распад органики в некоторых случаях могут оказывать влияние на успешность процесса воспроизводства, косвенно влияя на долговременные тренды популяционной динамики. В отдельных случаях усиление притока органического фосфора приводит далее к состоянию эвтрофикации и может сказаться на недостаточной аэрации мест размножения, привести к гипоксии у вылупившихся личинок. При массовой гибели икры еще ухудшится ситуация с расходом кислорода в водоеме. Нехватка органики приводит недостаточному для оптимального роста рыб развитию биомассы кормовых планктонных организмов. Система уравнений выживаемости конкурирующих особей поколения дополнена функциональным расширением, использующим итерационную модель динамики биогенных элементов, построенную на основе анализа процессов в экосистеме озера Чао. Блок модели расчёта притока и деструкции органики синхронизирован с непрерывно-дискретной вычислительной структурой, учитывающей взаимосвязанные изменения факторов смертности и темпов развития молоди рыб при переходах между обобщенными эколого-физиологическими этапами развития
Control of the bias tilt angles in nematic liquid crystals
This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in S. V. Yablonskii, K. Nakayama, S. Okazaki, M. Ozaki, K. Yoshino, S. P. Palto, M. Yu. Baranovich, and A. S. Michailov, Journal of Applied Physics 85, 2556 (1999) and may be found at https://doi.org/10.1063/1.369574
DNA Penetration into a Lysozyme Layer at the Surface of Aqueous Solutions
The interactions of DNA with lysozyme in the surface layer were studied by performing infrared reflection–absorption spectroscopy (IRRAS), ellipsometry, surface tensiometry, surface dilational rheology, and atomic force microscopy (AFM). A concentrated DNA solution was injected into an aqueous subphase underneath a spread lysozyme layer. While the optical properties of the surface layer changed fast after DNA injection, the dynamic dilational surface elasticity almost did not change, thereby indicating no continuous network formation of DNA/lysozyme complexes, unlike the case of DNA interactions with a monolayer of a cationic synthetic polyelectrolyte. A relatively fast increase in optical signals after a DNA injection under a lysozyme layer indicates that DNA penetration is controlled by diffusion. At low surface pressures, the AFM images show the formation of long strands in the surface layer. Increased surface compression does not lead to the formation of a network of DNA/lysozyme aggregates as in the case of a mixed layer of DNA and synthetic polyelectrolytes, but to the appearance of some folds and ridges in the layer. The formation of more disordered aggregates is presumably a consequence of weaker interactions of lysozyme with duplex DNA and the stabilization, at the same time, of loops of unpaired nucleotides at high local lysozyme concentrations in the surface layer
DNA Interaction with a Polyelectrolyte Monolayer at Solution—Air Interface
From MDPI via Jisc Publications RouterHistory: accepted 2021-08-19, pub-electronic 2021-08-22Publication status: PublishedFunder: Russian Science Foundation; Grant(s): № 21-13-00039The formation of ordered 2D nanostructures of double stranded DNA molecules at various interfaces attracts more and more focus in medical and engineering research, but the underlying intermolecular interactions still require elucidation. Recently, it has been revealed that mixtures of DNA with a series of hydrophobic cationic polyelectrolytes including poly(N, N-diallyl-N-hexyl-N-methylammonium) chloride (PDAHMAC) form a network of ribbonlike or threadlike aggregates at the solution—air interface. In the present work, we adopt a novel approach to confine the same polyelectrolyte at the solution—air interface by spreading it on a subphase with elevated ionic strength. A suite of techniques–rheology, microscopy, ellipsometry, and spectroscopy–are applied to gain insight into main steps of the adsorption layer formation, which results in non-monotonic kinetic dependencies of various surface properties. A long induction period of the kinetic dependencies after DNA is exposed to the surface film results only if the initial surface pressure corresponds to a quasiplateau region of the compression isotherm of a PDAHMAC monolayer. Despite the different aggregation mechanisms, the micromorphology of the mixed PDAHMAC/DNA does not depend noticeably on the initial surface pressure. The results provide new perspective on nanostructure formation involving nucleic acids building blocks
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