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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.

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Abstract

The present study was conducted by using mixed methods design to investigate the role of language aptitude in second language acquisition (SLA). The quantitative method involved Hungarian adults (N = 27) of two kinds of schools: a technical school and three different universities. These adults participated in completing the aptitude test called Hungarian Language Aptitude Test (HUNLAT). The qualitative part included an in-depth interview, which was conducted with six participants mainly focussing on their learning habits in order to examine if there is any correspondence between aptitude and language learning habits in this sample. Within this sample, males achieved significantly higher scores on the Grammar analysis task and older students scored significantly higher on three tasks; additionally, they scored significantly higher on the total score of the HUNLAT. Furthermore, those students who scored high on the aptitude test regard themselves to be successful and those who scored low regard themselves less successful language learners. The major pedagogical implication that can be drawn from this particular research is that there are many constructs that may influence language aptitude including language learning habits, motivation, and language learning strategies; thus, EFL teachers may reconsider the role of this construct in SLA.

Open access
Acta Veterinaria Hungarica
Authors: Bohumil Bielik, Ladislav Molnár, Vladimír Vrabec, Romana Andrášiová, Ivana Cingel'ová Maruščáková, Radomíra Nemcová, Juraj Toporčák, and Dagmar Mudroňová

Abstract

Scientists around the world are focusing their interest on the use of probiotics in honey bees as an alternative method of prophylaxis against causative agents of both American and European foulbrood. In our study we tested inhibitory activity against Paenibacillus larvae and the biofilm formation activity by various lactic acid bacteria isolated from honey bee guts or fresh pollen samples in the presence of different sugars added to the cultivation media. In addition, we tested the probiotic effect of a newly selected Apilactobacillus kunkeei V18 in an in situ experiment in bee colonies. We found antibacterial activity against P. larvae in four isolates. Biofilm formation activity of varying intensity was noted in six of the seven isolates in the presence of different sugars. The strongest biofilm formation (OD570 ≥ 1) was noted in A. kunkeei V18 in the presence of fructose; moreover, this isolate strongly inhibited the growth of P. larvae under laboratory conditions. Inhibition of P. larvae and Melissococcus plutonius by A. kunkeei V18 in situ was confirmed in a pilot study.

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Abstract

In this study investigation of plasmid-mediated mcr 1-5 resistance genes was performed among multidrug-resistant (MDR) colistin sensitive and resistant Klebsiella pneumoniae and Escherichia coli strains isolated in our laboratory. We aimed to evaluate automated system (Vitek-2), broth microdilution (BMD) reference method and chromogenic media performance. Totally 94 MDR K. pneumoniae and six E. coli isolates were included in the study. CHROMID® Colistin R agar (COLR) (bioMerieux, France) was used to determine the colistin resistance by chromogenic method. Standard PCR amplification was performed using specific primers to screen the plasmid-mediated mcr 1-5 genes. Sixty-one isolates were resistant to colistin and 39 were susceptible with reference BMD. The essential and categorical agreement of Vitek-2 was determined as 100 and 99%. The sensitivity of COLR medium was 100%, the specificity was 97.5%. In our study mcr-1 was detected in eight isolates, while other mcr genes were not detected. Due to the high sensitivity and specificity of the COLR medium, it can be used in routine diagnostics for the detection of colistin resistance. In our study we detected 8% prevalence of mcr-1 among MDR strains however, two mcr-1 positive isolates were found sensitive to colistin by BMD.

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Acta Microbiologica et Immunologica Hungarica
Authors: Tran Duc Anh Ly, Linda Hadjadj, Van Thuan Hoang, Ndiaw Goumbala, Thi Loi Dao, Sekene Badiaga, Herve Tissot-Dupont, Philippe Brouqui, Didier Raoult, Jean-Marc Rolain, and Philippe Gautret

Abstract

We aimed to assess the prevalence of pathogenic bacteria and resistance genes in rectal samples collected among homeless persons in Marseille, France. In February 2014 we enrolled 114 sheltered homeless adults who completed questionnaires and had rectal samples collected. Eight types of enteric bacteria and 15 antibiotic resistance genes (ARGs) were sought by real-time polymerase chain reaction (qPCR) performed directly on rectal samples. ARG-positive samples were further tested by conventional PCR and sequencing. We evidenced a 17.5% prevalence of gastrointestinal symptoms, a 9.6% prevalence of enteric pathogenic bacteria carriage, including Escherichia coli pathotypes (8.7%) and Tropheryma whipplei (0.9%). Only 2 persons carried blaCTX-M-15 resistance genes (1.8%), while other genes, including carbapenemase-encoding genes and colistin-resistance genes, (mcr-1 to mcr-6, mcr-8) were not detected. Our results suggest that sheltered homeless persons in Marseille do not have a high risk of harbouring gastrointestinal antibiotic resistant bacteria.

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Abstract

The aim of this study was to assess how red-eared sliders (Trachemys scripta elegans) respond to anaesthesia itself and coelioscopy. For that purpose, the turtles were anaesthetised with ketamine–medetomidine or propofol, and the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and the level of malondialdehyde (MDA) were determined by spectrophotometry. The possible genotoxic effects of the anaesthetic agents were estimated by comet assay. A total of 24 turtles were included in this study. The animals were divided into four groups according to the anaesthetic protocol and according to whether endoscopy would be performed. Significantly decreased activities of CAT were found only in the propofol group and in turtles undergoing coelioscopy. Both anaesthetic protocols induced significantly increased MDA levels, while no differences were observed after the intervention. A significant increase in GST activity was detected in turtles after both anaesthetic protocols, but after coelioscopy significant changes in GST activity were found only in the propofol group. However, no differences in SOD activity and no DNA damages were detected in either group. These findings suggest that ketamine–medetomidine may be more suitable anaesthetic agents in red-eared sliders than propofol.

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Abstract

Satellite thematic maps in geological field studies are an important tool for the delineation, interpretation, representation, and visualization of geological processes, while the development of seismic sections offers an increasingly detailed analysis of subsurface geology and inferring and understanding the subsurface structure of the earth. This combination promoted a fast-growing research in the fields of morphotectonics and neotectonics. The area under investigation is one of the most significant Iraqi places which includes several oil fields. The study area is located in northern Iraq and administratively follows Kirkuk governorate. Landscapes in this area are characterized by asymmetrical, cylindrical and extended folds. Kirkuk, Bai-Hasan and Qarachuq Anticlines reflect these structural elements and their fold axis trends towards northwest-southeast within the Zagros folded zone. The main objective of this study is to use the visual and digital interpretation of Landsat image to discriminate the sudden breaks and omissions of rock beds in the study area. Therefore, a morphotectonic map was created, the accurate location of the sudden breaks was provided and the zones affected by tectonic deformation, which left its imprint on the successive lithological units were detected. Seismic data were used to assess the tectonic impact on subsurface formations and their reflections on exposure rocks. The seismic lines were selected based on the locations of the identified sudden breaks as interpreted from satellite images. The hypothesis derived from this study is that the sudden breaks in the study area were triggered by a series of faults. In addition, the region was affected by the vertical stresses resulting from these faults and morphological aspects of the region were determined by the temporal variations of the above stresses.

Open access

Abstract

The study deals with the numerical analysis aspects that are necessary for identifying of modal parameters of the tower structure as the most important part of the horizontal axis wind turbine, which are basic for the dynamic response analysis. In the present study, the modal behavior of an actual 55-m-high steel tower of 850 KW wind turbine (GAMESA G52/850 model) is investigated by using three-dimensional (3D) Finite Element (FE) method. The model was used to identify natural frequencies, their corresponding mode shapes and mass participation ratios, and the suggestions to avoid resonance for tower structure under the action wind. The results indicate that there is a very good agreement with the fundamental vibration theory of Euler-Bernoulli beam with lamped masse in bending vibration modes. When the rotor of the wind turbine runs at the speed of less than or equal to 25.9 rpm it will not have resonant problems (stiff–stiff tower design). Furthermore, in case the rotor runs at the speed of between 25.9 and 30.8 rpm, the adequate controller is necessary in order to avoid the corresponding resonant susceptible area of the tower structure (soft–stiff tower design).

Open access

Abstract

Bacteriological cultures from cerebrospinal fluids (CSF) have less sensitivity and specificity compared to quantitative PCR (RT-PCR), and multiple facts still conduct to the increase of negative culture. The aims of this study are to determine the molecular epidemiology and the simultaneous detection of bacterial meningitis in Morocco by using RT-PCR and compared this molecular approach with culture method to improve the etiological diagnosis of meningitis. The CSFs were collected over one-year period in 2018 in different hospitals covering all regions of the Kingdom of Morocco, from patients with suspected meningitis. The results showed the confirmation rate per culture recorded a rate of 33% and the RT-PCR of 70%. Molecular epidemiology is predominant of Neisseria meningitidis followed by Streptococcus pneumoniae and a dramatic reduction in meningitis due to Haemophilus influenzae following the introduction of conjugate vaccine in 2007. Also, the epidemiological profile shows a sex ratio M/F of 1.4 and a median age of 2 years. The national distribution showed a predominant of meningococcal disease followed by pneumococcal disease, especially a dominance of N. meningitidis over S. pneumoniae in two regions and a slight predominance of S. pneumoniae in the other two regions over N. meningitidis. Our research shows that culture in our country has less sensitivity and specificity than RT-PCR in diagnosis of bacterial meningitis and that molecular biology technique at bacteriology laboratories is desirable for diagnosis, early management of meningitis cases and in the context of the surveillance of meningitis in Morocco in parallel with culture.

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