Physiology international最新文献

{"title":"The miR-1906 mimic attenuates bone loss in osteoporosis by down-regulating the TLR4/MyD88/NF-κB pathway.","authors":"H Xie,&nbsp;L Cao,&nbsp;L Ye,&nbsp;G Shan,&nbsp;W Song","doi":"10.1556/2060.2020.00042","DOIUrl":"https://doi.org/10.1556/2060.2020.00042","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39127527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The use of near-infrared spectroscopy for the evaluation of a 4-week rehabilitation program in patients with COPD.","authors":"Botond Szucs, Mate Petrekanits, Monika Fekete, Janos T Varga","doi":"10.1556/2060.2021.00185","DOIUrl":"10.1556/2060.2021.00185","url":null,"abstract":"<p><strong>Background: </strong>Near-infrared spectroscopy (NIRS) technology can evaluate muscle metabolism and oxygenation. NIRS-based oximeters can measure skeletal muscle oxygen delivery and utilization during static and dynamic work non-invasively. Our goal was to assess the value and usability of NIRS technology in chronic obstructive pulmonary disease (COPD) rehabilitation program.</p><p><strong>Methods: </strong>Forty patients with COPD participated in a 4-week inpatient rehabilitation program that included breathing exercises and personalized cycle/treadmill training adjusted to the functional capacity, physical activity and comorbidities of the patients. A NIRS muscle oxygen monitor was used to measure tissue oxygenation and hemoglobin levels. Total hemoglobin index, average muscle oxygenation, minimal and maximal muscle oxygenation were recorded before and after the rehabilitation program.</p><p><strong>Results: </strong>Rehabilitation resulted improvement in 6 min walking distance (6MWD:335.3 ± 110. vs. 398.3 ± 126.2 m; P < 0.01), maximal inspiratory pressure (MIP: 57.7 ± 22.7 vs. 63.6 ± 18.0 cmH2O; P < 0.01), chest wall expansion (CWE: 2.84 ± 1.26 vs, 4.00 ± 1.76 cm; P < 0.01), breath hold time (BHT: 25.8 ± 10.6 vs. 29.2 ± 11.6 s; P < 0.01) and grip strength (GS: 24.9 ± 11.9 vs. 27.0 ± 11.4 kg; P < 0.01). Quality of life improvement was monitored by COPD Assessment Test (CAT: 17.00 ± 8.49 vs. 11.89 ± 7.3, P < 0.05). Total hemoglobin index (tHb: 12.8 ± 1.3% vs. 12.8 ± 1.4), average muscle oxygenation (SmO2: 67.5 ± 14.4% vs. 65.2 ± 20.4%) showed a tendency for improvement. Maximal muscle oxygenation decreased (SmO2 max: 98.0 ± 20.5% vs. 90.1 ± 14.3%; P < 0.01). Minimal muscle oxygenation increased (SmO2 min: 42.6 ± 12.6% vs. 54.8 ± 14.3%; P < 0.01).</p><p><strong>Conclusions: </strong>NIRS results showed that muscle oxygenation and microcirculation can be described as a high-risk factor in COPD patients. The 4-week rehabilitation improves functional parameters, quality of life and tissue oxygenation levels in COPD patients.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39528090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Depression among predictors of intermittent claudication: A cross-sectional study.","authors":"Gergely Tóth-Vajna, Zsombor Tóth-Vajna, Barna Konkoly Thege, Piroska Balog","doi":"10.1556/2060.2021.00186","DOIUrl":"10.1556/2060.2021.00186","url":null,"abstract":"<p><strong>Purpose: </strong>The aim of the present cross-sectional study was to investigate the relationship between depression and intermittent claudication (IC), independently of traditional risk factors.</p><p><strong>Main methods: </strong>The sample consisted of 300 individuals (M age = 65.3 ± 8.7 years, 61.0% female) recruited from the offices of 33 general practitioners. Participants' medical history and the presence of major cardiovascular risk factors were recorded. Participants completed the Edinburgh Claudication Questionnaire. The role of depression (assessed by a shortened version of the Beck Depression Inventory) in predicting IC was examined using a binary logistic regression analysis - controlled for sex, age, hypertonia, diabetes, smoking, hypercholesterinemia, hazardous drinking, and body mass index (BMI).</p><p><strong>Results: </strong>The descriptive data indicated that the prevalence of depression was 57.9% in the IC subgroup and 16.1% in those free of IC. The bivariate analyses indicated that hypercholesterinemia, smoking, hazardous drinking, BMI, and depression were significantly associated with IC. Male sex and age showed a trend toward being a significant correlate of IC. Results of the multivariate analyses indicated that depressive symptomatology was significant in predicting IC (OR: 1.08 (1.05-1.11)), even after controlling for lifestyle and traditional risk factors such as smoking, hazardous drinking, and BMI. Among traditional risk factors, smoking (OR: 2.44 (1.26-4.74)), hazardous drinking (OR: 1.19 (1.02-1.40)), and hypercholesterinemia (OR: 2.17 (1.26-3.75)) showed a significant, positive relationship with IC.</p><p><strong>Conclusions: </strong>These results underscore the importance of a multidisciplinary approach that focuses on supporting health-related behavioral changes and managing mental health symptoms when providing care for patients with IC.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39528088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The \"GG\" genotype of rs26802 variant in the ghrelin gene is a potential protective factor against nonalcoholic fatty liver disease.","authors":"Gholamreza Rezamand,&nbsp;Touraj Mahmoudi,&nbsp;Seidamir Pasha Tabaeian,&nbsp;Hamid Farahani,&nbsp;Fatemeh Shahinmehr,&nbsp;Hossein Nobakht,&nbsp;Reza Dabiri,&nbsp;Asadollah Asadi,&nbsp;Fariborz Mansour-Ghanaei,&nbsp;Mohammad Reza Zali","doi":"10.1556/2060.2021.00183","DOIUrl":"https://doi.org/10.1556/2060.2021.00183","url":null,"abstract":"<p><strong>Background: </strong>Nonalcoholic fatty liver disease (NAFLD) is an emerging global chronic liver disease worldwide. Considering the powerful association between NAFLD, insulin resistance (IR) and obesity, as well as the key role of ghrelin in these metabolic disorders, we hypothesized that some single nucleotide polymorphisms (SNPs) of the ghrelin (GHRL) and ghrelin receptor (GHSR) genes might be associated with NAFLD.</p><p><strong>Methods: </strong>We conducted a case-control retrospective study of 150 cases with biopsy-proven NAFLD and 155 controls. The diagnosis of NAFLD was established before the start of the genotyping process. All the 305 subjects were genotyped for GHRL SNP rs26802 or -501T>G and GHSR SNP rs572169 or Arg159Arg using the PCR-RFLP method.</p><p><strong>Results: </strong>The GHRL rs26802 \"GG\" genotype compared with the \"TT\" genotype and \"TT+TG\" genotype appears to be a marker of decreased NAFLD susceptibility even after adjustment for confounding factors (P = 0.006; OR = 0.14, 95% CI = 0.03-0.56 and P = 0.003; OR = 0.16, 95% CI = 0.05-0.53, respectively). However, we observed no significant difference in genotype or allele frequencies between the cases and controls for GHSR SNP rs572169.</p><p><strong>Conclusions: </strong>These findings proposed, for the first time, that the GHRL rs26802 \"GG\" genotype has a protective effect against NAFLD. Nonetheless, this observation warrants further investigations in other populations.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39422290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The influence of external load variables on creatine kinase change during preseason training period.","authors":"Dániel Csala,&nbsp;Bence Márk Kovács,&nbsp;Péter Bali,&nbsp;Gábor Reha,&nbsp;Gergely Pánics","doi":"10.1556/2060.2021.30019","DOIUrl":"https://doi.org/10.1556/2060.2021.30019","url":null,"abstract":"<p><strong>Objective: </strong>The aim of the present study was to analyse the relationships between creatine kinase (CK) concentration, an indirect marker of muscle damage, and global positioning system (GPS)-derived metrics of a continuous two-week-long preseason training period in elite football.</p><p><strong>Design: </strong>Twenty-one elite male professional soccer players were assessed during a 14-day preseason preparatory period. CK concentrations were determined each morning, and a GPS system was used to quantify the external load. A generalized estimating equation (GEE) model was established to determine the extent to which the external load parameter explained post-training CK levels.</p><p><strong>Results: </strong>The GEE model found that higher numbers of decelerations (χ 2 = 7.83, P = 0.005) were most strongly associated with the post-training CK level. Decelerations and accelerations accounted for 62% and 11% of the post-training CK level, respectively, and considerable interindividual variability existed in the data.</p><p><strong>Conclusion: </strong>The use of GPS to predict muscle damage could be of use to coaches and practitioners in prescribing recovery practices. Based on GPS data, more individualized strategies could be devised and could potentially result in better subsequent performance.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9473830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perturbation-based balance assessment: Examining reactive balance control in older adults with mild cognitive impairments.","authors":"Lakshmi N Kannan,&nbsp;Tanvi S Bhatt","doi":"10.1556/2060.2021.00181","DOIUrl":"https://doi.org/10.1556/2060.2021.00181","url":null,"abstract":"<p><strong>Background: </strong>Older adults with mild cognitive impairment (OAwMCI) present subtle balance and gait deficits along with subjective memory decline. Although these presentations might not affect activities of daily living (ADLs), they attribute to a two-folded increase in falls. While changes occurring in volitional balance control during ADLs have been extensively examined among OAwMCI, reactive balance control, required to recover from external perturbations, has received little attention. Therefore, this study examined reactive balance control in OAwMCI compared to their healthy counterparts.</p><p><strong>Methods: </strong>Fifteen older adults with mild cognitive impairment (OAwMCI), fifteen cognitively intact older adults (CIOA) (>55 years), and fifteen young adults (18-30 years) were exposed to stance perturbations at three different intensities. Behavioral outcomes postural COM state stability, step length, step initiation, and step execution were computed.</p><p><strong>Results: </strong>Postural COM state stability was the lowest in OAwMCI compared to CIOA and young adults, and it deteriorated at higher perturbation intensities (P < 0.001). Step length was the lowest among OAwMCI and was significantly different from young adults (P < 0.001) but not from CIOA. Unlike OAwMCI, CIOA and young adults increased their step length at higher perturbation intensities (P < 0.001). OAwMCI showed longer recovery step initiation times and shorter execution times compared to CIOA and young adults at higher perturbation intensities (P < 0.001).</p><p><strong>Conclusion: </strong>OAwMCI exhibit exacerbated reactive instability and are unable to modulate their responses as the threat to balance control altered. Thus, they are at a significantly higher risk of falls than their healthy counterparts.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39422289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ferulic acid attenuates osteoporosis induced by glucocorticoid through regulating the GSK-3β/Lrp-5/ERK signalling pathways.","authors":"Wei Zhou,&nbsp;Bo Chen,&nbsp;Jingbo Shang,&nbsp;Renbo Li","doi":"10.1556/2060.2021.00180","DOIUrl":"https://doi.org/10.1556/2060.2021.00180","url":null,"abstract":"<p><strong>Objective: </strong>To evaluate in-vivo and in-vitro effects of ferulic acid (FA) on glucocorticoid-induced osteoarthritis (GIO) to establish its possible underlying mechanisms.</p><p><strong>Methods: </strong>The effects of FA on cell proliferation, cell viability (MTT assay), ALP activity, and mineralization assay, and oxidative stress markers (ROS, SOD, GSH LDH and MDA levels) were investigated by MC3T3-E1 cell line. Wistar rats received standard saline (control group) or dexamethasone (GC, 2 mg-1 kg) or DEX+FA (50 and 100 mg-1 kg) orally for 8 weeks. Bone density, micro-architecture, bio-mechanics, bone turnover markers and histo-morphology were determined. The expression of OPG, RANKL, osteogenic markers, and other signalling proteins was assessed employing quantitative RT-PCR and Western blotting.</p><p><strong>Results: </strong>The findings indicated the elevation of ALP mRNA expressions, osteogenic markers (Runx-2, OSX, Col-I, and OSN), and the β-Catenin, Lrp-5 and GSK-3β protein expressions. FA showed the potential to increase MC3T3-E1 cell differentiation, proliferation, and mineralization. FA increased oxidative stress markers (SOD, MDA, and GSH) while decreasing ROS levels and lactate dehydrogenase release in GIO rats. The OPG/RANKL mRNA expression ratio was increased by FA, followed by improved GSK-3β and ERK phosphorylation with enhanced mRNA expressions of Lrp-5 and β-catenin.</p><p><strong>Conclusion: </strong>These findings showed that FA improved osteoblasts proliferation with oxidative stress suppression by controlling the Lrp-5/GSK-3β/ERK pathway in GIO, demonstrating the potential pathways involved in the mechanism of actions of FA in GIO therapy.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39422291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aerobic interval training improves irisin and chemerin levels of both liver and visceral adipose tissues and circulating asprosin in rats with metabolic syndrome.","authors":"Fereshteh Ahmadabadi,&nbsp;Hossein Nakhaei,&nbsp;Mehdi Mogharnasi,&nbsp;Chun-Jung Huang","doi":"10.1556/2060.2021.00182","DOIUrl":"https://doi.org/10.1556/2060.2021.00182","url":null,"abstract":"<p><p>The perturbation of adipokinetic hormones, such as irisin, chemerin, and asprosin has been reported to participate in pathological conditions (e.g., insulin resistance) and chronic inflammation. However, exercise training has been long established as an effective intervention for prevention and treatment of these chronic and metabolic diseases. This study was to examine the effects of aerobic continuous training (ACT) and aerobic interval training (AIT) on irisin and chemerin levels of liver tissue (LT) and visceral adipose tissue (VAT), circulating asprosin, and their relationships with cardiometabolic risk factors in rats with metabolic syndrome (MetS). Thirty-two male Wistar rats were randomly divided into four equal groups: normal control (N-Ctr), control (Ctr-MetS), ACT, and AIT. After familiarization, rats with exercise intervention performed either ACT or AIT five times a week over eight weeks. The level of irisin in both ACT and AIT groups was higher than the Ctr-MetS group in LT and VAT, with a greater improvement of LT level observed in AIT vs. ACT groups. Furthermore, the level of chemerin in LT and VAT was lower in both ACT and AIT groups than the Ctr-MetS group, whereas only AIT group exhibited a reduction of serum asprosin when compared to ACT and Ctr-MetS, along with the improvements of cardiometabolic markers, such as HOMA-IR and lipid profile. These findings may support the efficiency and effectiveness of AIT intervention in the modulation of these novel metabolic hormones and cardiometabolic risk factors for reduced risk of metabolic syndrome.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39422292","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An autophagy-related long non-coding RNA signature for patients with colorectal cancer.","authors":"Dongyan Zhao, Xizhen Sun, Sidan Long, Shukun Yao","doi":"10.1556/2060.2021.00125","DOIUrl":"10.1556/2060.2021.00125","url":null,"abstract":"<p><strong>Aim: </strong>Long non-coding RNAs (lncRNAs) have been identified to regulate cancers by controlling the process of autophagy and by mediating the post-transcriptional and transcriptional regulation of autophagy-related genes. This study aimed to investigate the potential prognostic role of autophagy-associated lncRNAs in colorectal cancer (CRC) patients.</p><p><strong>Methods: </strong>LncRNA expression profiles and the corresponding clinical information of CRC patients were collected from The Cancer Genome Atlas (TCGA) database. Based on the TCGA dataset, autophagy-related lncRNAs were identified by Pearson correlation test. Univariate Cox regression analysis and the least absolute shrinkage and selection operator analysis (LASSO) Cox regression model were performed to construct the prognostic gene signature. Gene set enrichment analysis (GSEA) was used to further clarify the underlying molecular mechanisms.</p><p><strong>Results: </strong>We obtained 210 autophagy-related genes from the whole dataset and found 1187 lncRNAs that were correlated with the autophagy-related genes. Using Univariate and LASSO Cox regression analyses, eight lncRNAs were screened to establish an eight-lncRNA signature, based on which patients were divided into the low-risk and high-risk group. Patients' overall survival was found to be significantly worse in the high-risk group compared to that in the low-risk group (log-rank p = 2.731E-06). ROC analysis showed that this signature had better prognostic accuracy than TNM stage, as indicated by the area under the curve. Furthermore, GSEA demonstrated that this signature was involved in many cancer-related pathways, including TGF-β, p53, mTOR and WNT signaling pathway.</p><p><strong>Conclusions: </strong>Our study constructed a novel signature from eight autophagy-related lncRNAs to predict the overall survival of CRC, which could assistant clinicians in making individualized treatment.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39152127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The shear resistance of a member without shear reinforcement according to Eurocode 2; the error of the calculated value and the mechanical explanation of the problem.","authors":"Béla Bogdándy","doi":"10.1556/1848.2021.00236","DOIUrl":"10.1556/1848.2021.00236","url":null,"abstract":"<p><p>In this paper the shear resistance of a member without shear reinforcement according to Eurocode 2 is investigated. This expression, as most expressions of design codes typically used to estimate the nominal shear resistance, has been created based on experimental investigations. It will be verified that in case of non-prestressed reinforced concrete member without stirrups, the shear resistance is carried by the shear resistance of the compressive zone; and the shear resistance given by the empirical expression of Eurocode 2 is actually the shear resistance of the compressive zone.Knowing the mechanical background of the empirical expressions of Eurocode 2, the limits of its applicability can be shown, thus its error can be predicted. Using the reports of experimental investigations, it is easy to find cases to prove the correctness of the error-prediction. In this paper simple modifications will be suggested to Eurocode 2 shear design procedures, by which a more consistent level of safety can be ensured.</p>","PeriodicalId":20058,"journal":{"name":"Physiology international","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39123555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}