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Abstract

Based on the current literature, the link between Achilles tendon moment arm length and running economy is not well understood. Therefore, the aim of this study was to further investigate the connection between Achilles tendon moment arm and running economy and the influence of Achilles tendon moment arm on the function of the plantarflexor muscle-tendon unit during running.

Ten male competitive marathon runners volunteered for this study. The participants ran on a treadmill at two running speeds: 3 and 3.5 m s−1. During running the oxygen consumption, lower leg kinematics, electrical activity of plantar flexor muscles, and fascicle behavior of the lateral gastrocnemius were measured simultaneously. On the second occasion, an MRI scan of the right leg was taken and used to estimate the Achilles tendon moment arm length.

There was a negative correlation between running economy and the body height normalized moment arm length at both selected speeds (r = −0.68, P = 0.014 and r = −0.70, P = 0.01). In addition, Achilles tendon moment arm length correlated with the amplitude of the ankle flexion at both speeds (r = −0.59, P = 0.03 and r = −0.60, P = 0.03) and with the electrical activity of the medial gastrocnemius muscle at 3 m s−1 speed (r = −0.62, P = 0.02). Our finding supports the concept that a longer moment arm could be beneficial for distance runners.

Open access

Abstract

In this study, the ability of microRNA-1906 (miR-1906) to attenuate bone loss in osteoporosis was evaluated by measuring the effects of a miR-1906 mimic and inhibitor on the cellular toxicity and cell viability of MC3T3‐E1 cells. Bone marrow-derived macrophage (BMM) cells were isolated from female mice, and tartrate-resistant acid phosphatase signalling was performed in miR-1906 mimic-treated, receptor-activated nuclear factor kappa-B (NF-κB) ligand (RANKL)-induced osteoclasts. In-vivo, osteoporosis was induced by ovariectomy (OVX). Rats were treated with 500 nmol/kg of the miR-1906 mimic via intrathecal administration for 10 consecutive days following surgery. The effect of the miR-1906 mimic on bone mineral density (BMD) in OVX rats was observed in the whole body, lumbar vertebrae and femur. Levels of biochemical parameters and cytokines in the serum of miR-1906 mimic-treated OVX rats were analysed. The mRNA expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), p-38 and NF-κB in tibias of osteoporotic rats (induced by ovariectomy) was observed using quantitative reverse-transcription polymerase chain reaction. Treatment with the miR-1906 mimic reduced cellular toxicity and enhanced the cell viability of MC3T3‐E1 cells. Furthermore, osteoclastogenesis in miR-1906 mimic-treated, RANKL-induced osteoclast cells was reduced, whereas the BMD in the miR-1906 mimic-treated group was higher than in the OVX group of rats. Treatment with the miR-1906 mimic also increased levels of biochemical parameters and cytokines in the serum of ovariectomised rats. Finally, mRNA expression levels of TLR4, MyD88, p-38 and NF-κB were lower in the tibias of miR-1906 mimic-treated rats than in those of OVX rats. In conclusion, the miR-1906 mimic reduces bone loss in rats with ovariectomy-induced osteoporosis by regulating the TLR4/MyD88/NF‐κB pathway.

Restricted access

Abstract

Introduction

Surrogate endpoints are widely used in clinical trials, especially in situations where the endpoint of interest is not directly observable or to avoid long trial periods. A typical example for this case is frequently found in clinical trials in oncology, where overall survival (OS) as endpoint of interest and progression free survival (PFS) as surrogate endpoint are discriminated.

Methods

Based on the perspective of case definitions on surrogate endpoints, we provide a formal definition of such endpoints followed by a description of the structure of surrogate endpoints.

Results

Surrogate endpoints can be considered as case definitions for the endpoint of interest. Therefore, the performance of surrogate endpoints can be described using the classical terminology of diagnostic tests including sensitivity and specificity. Since such endpoints always focus on sensitivity with necessarily reduced specificity, efficacy estimates based on such endpoints are in general biased.

Conclusion

The abovementioned has to be taken into account while interpreting the results of clinical trials and should not be ignored while planning or conducting a study.

Open access

Abstract

After the first description of OXA-48 type carbapenemase, it has become endemic in Europe, Mediterranean and North African countries in a short time. OXA-48 carbapenemase is the most difficult type to determine and accurate diagnosis is crucial especially in endemic areas.

The CarbaNP test was described as a rapid phenotypic evaluation method of carbapenemases activity. Sensitivity and specifity of this test were high within all carbapenemases genes. In our study, we evaluated the efficacy of CarbaNP test in routine laboratories located in an endemic area of OXA-48 producing Enterobacterales.

A total of 53 Enterobacterales isolates were included in this study. Antimicrobial susceptibility of the isolates to imipenem, meropenem and ertapenem was determined. Polymerase Chain Reaction (PCR) was carried out for the detection of carbapenemases genes (bla KPC, bla NDM, bla BIC, bla IMP, bla VIM, bla SPM, bla AIM, bla DIM, bla GIM, bla SIM, and bla OXA-48). The Carba NP test was performed as in the protocol described previously.

Altogether 31 isolates (58.4%) were bla OXA-48 positive (18 Klebsiella pneumoniae, 8 Escherichia coli, 2 Serratia marcescens, 1 Enterobacter aerogenes, 1 Pantoea agglomerans and 1 Morganella morganii). Among these isolates 3 (5.6%) and 2 (3.7%) isolates were also positive for bla VIM and bla SPM, respectively.

The sensitivity and specifity of CarbaNP test were found 64.5, and 68.2% respectively. It was observed that determination of positive isolates is hard to distinguish and subjective.

The CarbaNP test has suboptimal results and low of sensitivity and specifity for detection of OXA-48 producing Enterobacterales, and not suitable for detection of bla OXA-48 positive isolates in routine laboratories in endemic areas.

Restricted access

Abstract

The 2010–2012 euro crisis prompted a wave of institutional reforms in the European Economic and Monetary Union (EMU), and one of the most remarkable changes was the creation of a permanent bailout facility for troubled sovereigns. The birth of the European Stability Mechanism (ESM) in 2012 was preceded by harsh debates, reflecting a conflict between a German view of country-level responsibility and French-Italian calls for more risk sharing. These tensions have remained ever since, which was also highlighted by conflicts regarding the ESMs overhaul at the end of 2019. Concerns of Italy then drew attention to the fact that a wide range of issues prevented the community from finalizing the post-crisis structure of the eurozone. This paper focuses on the evolution of the EMU financial assistance framework up until the latest efforts for its reform. We analyse the impact of related policy announcements on changes in sovereign bond yields of Italy, Spain, Portugal and Ireland (i.e. the most vulnerable countries during the euro crisis). Our findings show that news on bailout arrangements significantly contributed to a contemporaneous moderation of periphery bond yields, especially in the case of shorter maturities. This result hints at the role of common facilities in supporting financial stability. To enhance this feature, a ‘package approach’ (i.e. multiple reforms together, as stressed by Italy) may well need to be considered. Such a broad perspective can help strengthen the euro area once the acute threat of the coronavirus pandemic is averted.

Open access

Abstract

In embedded systems that necessarily require a steady source of power and (or) attaches to a sensor(s), there are opportunities to mix small batteries to supply such power. The aim of this research is to optimize the geometry and shape of piezoelectric cantilevers to harvest more power. Several piezoelectric cantilever geometries with various shapes (rectangular, triangular, circular, and trapezoidal cross section) are tested in COMSOL multiphysics simulator to find the best geometry that provides the highest accomplishable power. The most efficient geometry was found to be conferred by the trapezoidal, cross section cantilever. Next, another improvement method was applied to maximize the harvested power of the cantilever by modifying the shape of the trapezoidal cantilever structure through increasing the number of its faces. The results demonstrated that the highest output power (36 mW) was produced by the four faces, trapezoidal cross section design of cantilever.

Open access

Abstract

Rauwolfia tetraphylla L., is an important medicinal plant in Apocynaceae family and is recognized as an alternative source to Rauwolfia serpentina L., in terms of anti-hypertensive alkaloid production i.e. reserpine. In view of this, the present study is conducted to estimate the reserpine content in different parts (leaf, stem and root) of field grown plants (2 years old), tissue cultured plantlets (R1) (two months old) and cell suspensions cultures (two months old with and without precursor feeding) of R. tetraphylla by using high performance liquid chromatography (HPLC) technique. Overall maximum content of reserpine (in %) was estimated from the root samples. Roots of field grown plants has recorded high percent of reserpine (0.39%) followed by roots of tissue cultured plantlets (0.35%) and root callus based cell suspension cultures (0.38 %) which was fed with precursor amino acid (100 mg/L of tryptophan). In control type of root callus based cell suspension cultures, reserpine content was quantified as 0.14%; by precursor feeding (100 mg/L of tryptophan) it was enhanced to 0.38%. In conclusion, the reserpine content (0.35 and 0.38%) produced by the roots of tissue cultured plantlets (R1) and 100 mg/L tryptophan fed root callus based cell suspensions was comparable to that of the reserpine content (0.39%) of root parts of field grown plants. The present study demonstrates the reserpine production by in vitro cell suspension cultures throughout the year without sacrificing the medicinal plants.

Open access

Abstract

Multinational enterprises (MNEs) use different methods and structures for base erosion and profit shifting (BEPS) to optimize the tax liability of the group. It is of great interest to the relevant countries to be able to identify such practices and react with appropriate measures. The objective of this paper is to verify whether selected MNEs engaged in the digital economy tend to shift profits from the Czech Republic to jurisdictions with lower taxation using the tax evasion rate (TER) indicator and the transactional net margin method (TNNM). Since the TER method has not been tested yet, this paper also aims to demonstrate its application on real world data and to evaluate its usability. On a sample of five MNEs, the analysis showed a potential tendency to shift profits within Europe for four MNEs (Amazon, Apple, Google and Uber) and a potential tendency to shift profits specifically from the Czech Republic for one MNE (Amazon). The analysis shows that TER is suitable as a preliminary indication of possible risks, rather than their exact quantification.

Open access