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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

This paper involves the study on the hardened and durability properties of the concrete at two different grades containing silica fume (SF) with various replacement percentages. Investigation on the performance of the SF was performed for M25 and M40 grades concrete with 0, 5, 10, and 15 % replacement levels at 7, 14, 28, and 90 days. The behavior of SF on the autogenous shrinkage of the concrete was studied for both the grades of concrete in the sealed (SC) and unsealed conditions (USC). The workability of the SF concrete was examined at various levels of replacement by the slump cone test. The hardened properties of the SF concrete were investigated through the estimation of compressive strength (CS) and elastic modulus (EM) at 7, 14, 28, and 90 days, respectively. Acid attack was conducted at 28 days and autogenous shrinkage of the SF concrete was investigated using length comparator at 28 day in SC and USC. Results indicate that upon increase in the percentage of SF, the hardened properties of the concrete increases at higher ages of curing and the shrinkage of the concrete tends to increase for both the grades of concrete.

Open access

Abstract

Background and aims

The World Health Organization included gaming disorder (GD) in the eleventh revision of International Classification of Diseases in 2019. Due to the lack of diagnostic tools for GD, a definition has not been adequately applied. Therefore, this study aimed to apply an operationalized definition of GD to treatment-seekers. The relationship between the diagnoses of GD and Internet gaming disorder (IGD) in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders was also examined. Methods: Study participants comprised 241 treatment-seekers who had engaged in excessive gaming and experienced related problems. Psychiatrists applied the GD diagnostic criteria to the participants using a diagnostic form developed for this study. Information on gaming behavior and functional impairment was obtained through face-to-face interviews conducted by clinical psychologists. Results: In total, 78.4 and 83.0% of the participants fulfilled the GD and IGD diagnostic criteria, respectively. The sensitivity and specificity of GD diagnosis were both high when the IGD diagnosis was used as the gold standard. Participants with GD preferred online PC and console games, spent significantly more time gaming, and showed a higher level of functional impairment compared to those who did not fulfill the GD diagnostic criteria. Discussion and Conclusion: The definition of GD can be successfully applied to treatment-seekers with excessive gaming and related problems. A high concordance of GD and IGD diagnoses was found in those participants with relatively severe symptoms. The development and validation of a diagnostic tool for GD should be explored in future studies.

Open access

Abstract

Background and aims

Problematic Internet Use (PIU) might be a potential mental health problem. Few studies have investigated the relative contribution of individual and family factors in the development of PIU in early adolescence. The aim of the current study was to model the relationship between attachment styles, negative beliefs about worry, and PIU in early adolescence.

Methods

Five hundred and thirty-eight Italian early adolescents (51% females, M age = 12.7 years, SD = 0.87) were included in this study. The pattern of relationships specified by the theoretical model was examined through path analysis.

Results

Results showed that avoidance (mother) and anxiety (father) were directly associated with PIU. Anxiety (mother) and avoidance (father) were indirectly associated with PIU via negative beliefs about worry.

Discussion and conclusions

Overall, our findings show that attachment toward mother and father are differently linked to PIU and that negative beliefs about worry may play a mediating role in the association between attachment and PIU. Findings are discussed within clinical and preventive implications.

Open access
Journal of Behavioral Addictions
Authors: Natale Canale, Tania Moretta, Luca Pancani, Giulia Buodo, Alessio Vieno, Mario Dalmaso, and Joël Billieux

Abstract

Background and aims

Problematic smartphone use (PSU) has been described as a growing public health issue. In the current study, we aimed to provide a unique and comprehensive test of the pathway model of PSU. This model posits three distinct developmental pathways leading to PSU: (1) the excessive reassurance pathway, (2) the impulsive pathway and (3) the extraversion pathway.

Methods

Undergraduate students (n = 795, 69.8% female, mean age = 23.80 years, sd = 3.02) completed online self-report measures of PSU (addictive use, antisocial use and dangerous use) and the psychological features (personality traits and psychopathological symptoms) underlying the three pathways.

Results

Bayesian analyses revealed that addictive use is mainly driven by the excessive reassurance pathway and the impulsive pathway, for which candidate etiopathological factors include heightened negative urgency, a hyperactive behavioural inhibition system and symptoms of social anxiety. Dangerous and antisocial use are mainly driven by the impulsive pathway and the extraversion pathway, for which candidate etiopathological factors include specific impulsivity components (lack of premeditation and sensation seeking) and primary psychopathy (inclination to lie, lack of remorse, callousness and manipulativeness).

Discussion and conclusions

The present study constitutes the first comprehensive test of the pathway model of PSU. We provide robust and original results regarding the psychological dimensions associated with each of the postulated pathways of PSU, which should be taken into account when considering regulation of smartphone use or tailoring prevention protocols to reduce problematic usage patterns.

Open access

Abstract

In this study, a new microextraction method based on hydrophobic deep eutectic solvents was developed for the extraction and preconcentration of organophosphorus pesticides from beverage samples. The hydrophobic deep eutectic solvents were synthesized from choline chloride and 4-chlorophenol. Main experimental parameters of the microextraction method were investigated to improve the extraction efficiency. The proposed method achieved a satisfactory linear range between 50 and 2,000 μg L−1 with coefficient of determination greater than 0.9939. The extraction recoveries and enrichment factor of five organophosphorus pesticides at three added levels ranged from 71.68 to 113.18% and 71.43–111.11 were obtained with the acceptable relative standard deviation ranged from 1.37 to 11.92%. Limits of detection and quantification were found to be 0.05–0.3 μg L−1 and 0.17–1 μg L−1, respectively. Finally, the methods were successfully applied for the determination of five organophosphorus pesticide in orange juice and green tea.

Open access

Abstract

We sought to estimate the prevalence of lifetime psilocybin use among a national sample of US adults ages 18 and older and associated demographic/substance use correlates. Pooled data from the 2015–2018 National Survey on Drug Use and Health were utilized among 168,650 individuals 18 years or older. An estimated 9.68% of individuals reported lifetime use of psilocybin. Differences were found among demographics, drug use, and sexual identity, with bisexual identification being associated with greater lifetime use. Nearly two-thirds of individuals who have ever used Lysergic acid diethylamide (LSD), methamphetamine, and/or heroin also reportedly used psilocybin. Findings from the present study can inform harm reduction efforts and behavioral health messaging.

Open access

Összefoglaló. Bevezetés: A diffúz aortobiiliacalis érszakasz occlusiv betegségének kezelésére alkalmazott aortobifemoralis bypass szerepe csökken az endovascularis műtétek térnyerése miatt. Célkitűzés: A vizsgálat célja volt a modern invazív kezelés korszakában a perioperatív és a hosszú távú eredmények elemzése aortobiiliacalis bypass után, melyek összehasonlíthatók az endovascularis megoldások eredményeivel. Módszerek: A retrospektív, egycentrumú vizsgálat során a Semmelweis Egyetem Városmajori Szív- és Érgyógyászati Klinikájának Érsebészeti és Endovaszkuláris Tanszékén 2006. 01. 01. és 2017. 12. 31. között occlusiv aortoiliacalis atherosclerosis miatt primer aortobifemoralis bypass műtéten átesett 419 beteg (átlagéletkor: 62,2 év, SD: ± 8,22; 224 férfi, 53%) adatait elemeztük. Eredmények: A posztoperatív 30 napon belüli mortalitás 5,01%, a késői mortalitás 10,98% és 29,59% volt 12, illetve 60 hónap után. A betegek 12,57%-ánál történt korai reoperáció, késői reoperáció 32 (8%) betegnél vált szükségessé. A graft elsődleges nyitva maradása 88,65% és 81,15% volt 12, illetve 60 hónap után. 21 betegnél történt amputáció (6,29%); 57,14%-ban femoralis, 35,71%-ban cruralis szinten, 7,14%-ban a boka szintje alatt. Az amputációkra 35,71%-ban a bypasst követő 30 napon belül, további 35,71%-ban 2 éven belül került sor. Az esetek 35,63%-ában lépett fel egyéb szövődmény; a leggyakoribbak: műtétet igénylő posztoperatív hernia (6,89%), cardiovascularis szövődmény (4,19%), lágyéki nyirokcsorgás vagy sebgyógyulási zavar (4,79%). Következtetés: Eredményeink alapján e betegcsoportban az aortobifemoralis bypass elfogadható, de nem jelentéktelen perioperatív halálozással és magas morbiditással jár. A graft hosszú távú nyitva maradása jó, de az újabb érműtét mind rövid, mind hosszú távon relatíve gyakori. A kevésbé invazív technikák eredményeinek összehasonlítása indokolt a hosszú szakaszú (TASC C, D) elváltozások esetén. Orv Hetil. 2021; 162(3): 99–105.

Summary. Introduction: The role of aorto-bifemoral bypass in the treatment of diffuse aorto-biiliac occlusive disease decreases in the era of endovascular surgery. Objective: The aim of the study was to analyse the early and long-term postoperative results of aorto-bifemoral bypass in a recent time period. These results may be used as a baseline to compare the results of endovascular procedures. Methods: In a retrospective, single-center study, the data of 419 patients (mean age: 62.2 years, SD: ± 8.22; 224 men, 53%) who underwent primary aorto-bifemoral bypass due to occlusive aorto-iliac atherosclerosis from 01. 01. 2006 to 31. 12. 2017 at the Department of Vascular and Endovascular Surgery of Semmelweis University Heart and Vascular Center were analysed. Results: Postoperative mortality within 30 days was 5.01%, late mortality was 10.98% and 29.59% after 12 and 60 months, respectively. 12.57% of the patients needed early reoperation and late reoperation was required in 32 cases (8%). The primary graft patency was 88.65% and 81.15% after 12 and 60 months, respectively. 21 patients underwent amputation (6.29%); 57.14% at the femoral level, 35.71% at the crural level and 7.14% below the ankle level. Amputations were performed in 35.71% of the cases within 30 days after the bypass and an additional 35.71% within 2 years. Other complications occurred in 35.63% of the cases; the most common causes were postoperative hernia requiring surgery (6.89%), cardiovascular complication (4.19%) and inguinal wound healing disorders (4.79%). Conclusion: Based on our results, aorto-bifemoral bypass surgery is associated with acceptable but not insignificant perioperative mortality and high morbidity in this group of patients. The graft patency is favourable in the long term, however, additional vascular reintervention is common in short and long term as well. Short- and long-term results of percutaneous endovascular techniques in diffuse aorto-biiliac disease (TASC C and D lesions) are suggested to be compared to these recent results of open surgery. Orv Hetil. 2021; 162(3): 99–105.

Open access