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Abstract

Background

The arylidene indanone scaffold has contributed many lead molecules in chemotherapeutic anticancer agent research.

Objectives

To determine the oxidant-scavenging activities and antiproliferative activity of (2E)-2-benzylidene-4,7-dimethyl-2,3-dihydro-1H-inden-1-one (MLT-401), an arylidene indanone derivative.

Methods

Jurkat cells, primary lymphocytes, and Vero cells were treated with MLT-401. Antioxidant properties of MLT-401 were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH)-based, 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS)-based, and ferric-reducing antioxidant potential (FRAP) assays. Inhibition of cell proliferation was determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide-based assay. Nuclear status was determined using a DNA fragmentation assay, and cell cycle stage was analyzed by flow cytometry. Mitochondrial membrane enzyme activities were measured using colorimetric methods.

Results

The antioxidant assays gave MLT-401 half maximal inhibitory concentration (IC50) values of 1611 nM (DPPH-based assay), 2115 nM (ABTS-based assay), and 1586 nM (FRAP assay). MLT-401 inhibited proliferation of Jurkat cells with a concentration for 50% of maximal inhibition of cell proliferation (GI50) of 341.5 nM, being 12- and 9-fold less than GI50 concentrations for normal lymphocytes and Vero cells, respectively. MLT-401 caused nuclear fragmentation and DNA laddering as seen by electrophoresis. Jurkat cells showed a time-dependent accumulation of sub G0/G1 cells after MLT-401 treatment. Mitochondrial membrane-bound Na+/K+ ATPase, Ca2+ ATPase, and Mg2+ ATPase activities were inhibited by MLT-401 in a dose-dependent manner.

Conclusion

MLT-401 possesses significant antiproliferative activity and scavenges free radicals released through mitochondrial membrane damage in a Jurkat cell line model of cancer cells. Further investigation of MLT-401 as a chemotherapeutic anticancer agent and development of other arylidene indanone analogues are warranted. A detailed elucidation of mechanistic pathways is required for further development.

Abstract

The back squat is widely used in strength training programs. Alternatively, the belt squat has been gaining popularity since it loads the weight on the hips, as opposed to the shoulders and spine. The purpose of this study was to determine whether using a belt squat would result in less lumbar extensor activation while providing similar excitation of other prime mover and stabilizer musculature. Ten participants (9 males, 1 female; age 29.3 ± 4.9 years; body mass 96.2 ± 17.8 kg) who regularly trained both belt squats and back squats performed three sets of 5 repetitions with 100% bodyweight for each exercise. Peak and integrated muscle activity was calculated and normalized to a maximum voluntary isometric contraction. A one-way ANOVA (p < 0.05) was used to compare conditions. Belt squatting decreased lumbar erector impulse (45.4%) and peak (52.0%) activation as compared to the back squat. Belt squatting did not alter activation of the lower extremities except for a decrease in the gluteus maximus (35.2% impulse and 32.1% peak), gluteus medius (54.1% impulse and 55.2% peak). Furthermore, belt squatting reduced activation of the rectus abdominus (44.3% impulse; 31.1% peak), and external obliques (45.8% impulse; 53.7% peak) as compared to back squatting. Our results suggest belt squatting provides similar muscular demands for the quadriceps, hamstrings, and plantar flexors, but is less demanding of trunk stabilizers, and gluteual muscles. Belt squats may be a suitable alternative to back squats in order to avoid stressing low back or trunk musculature.

Abstract

This randomized cross-over study examined the effects of typical static and dynamic stretching warm-up protocols on repeated-sprint performance. Thirteen young female handball players performed a 5 min aerobic warm-up followed by one of three stretching protocols for the lower limbs: (1) static stretching, (2) dynamic-ballistic stretching, and (3) no stretching before performing five all-out sprints on a cycle ergometer. Each protocol was performed on a different occasion, separated by 2-3 days. Range of movement (ROM) was also measured before and after the warm-up protocols with a sit-and-reach test. Fixed and random effects of each stretching protocol on repeated sprint performance were estimated with mixed linear modeling and data were evaluated via standardization and magnitude-based inferences. In comparison to no stretching, there were small increases in ROM after dynamic stretching (12.7%, ±0.7%; mean, ±90% confidence limits) and static stretching (19.2%, ±0.9%). There were small increases in the average power across all sprints with dynamic stretching relative to static stretching (3.3%, ±2.4%) and no stretching (3.0%, ±2.4%) and trivial to small increases in the average power in the 1st and 5th trials with dynamic stretching compared to static stretching (3.9%, ±2.6%; 2.6%, ±2.6%, respectively) and no stretching (2.0%, ±2.7%; 4.1%, ±2.8%, respectively). There were also trivial and small decreases in power across all sprints with static relative to dynamic stretching (-1.3%, ±2.8%) and no stretching (-3.5%, ±2.9%). Dynamic stretching improved repeated-sprint performance to a greater extent than static stretching and no stretching.

Abstract

Pulmonary alveolar proteinosis (PAP) is a rare disease, certainly underdiagnosed, characterised by the intra-alveolar accumulation of a milky fluid rich in phospholipids and lipoproteins derived from alveolar surfactant, positive in periodic acid-Schiff staining. The alveolar macrophage plays a major role in the pathogenesis of PAP, and its role in the turn-over of alveolar surfactant is being altered by various mechanisms.

More than 90% of cases of PAP are primary autoimmune, characterised by the presence in serum of circulating autoantibodies against granulocyte-macrophages colony-stimulating factor. Other causes of PAP are genetic, secondary to other diseases or to exposure to different agents.

The evolution of the disease is unpredictable, from spontaneous remission to progression despite treatment towards pulmonary fibrosis and chronic severe respiratory failure. The gold standard of therapy is the whole lung lavage, other treatments are being still in evaluation.

The article presents a few cases that illustrate different patterns in the evolution of PAP.

Abstract

Personality traits, especially in sport are modulatory factors of athletes’ behavior – his/ her conscientiousness, the will to achieve an aim, perseverance and motivation of activity. Not only are biological predispositions related to anatomical or biochemical traits of success, but they are also largely determined by personality traits that result from genetic factors. In our research we joined tests of athlete’s personality in correlation with genotypes of the dopamine transporter (DAT1) gene polymorphism. The selection of this polymorphism was based on previous reports connecting the influence of dopamine with motivation and numerous arguments supporting its correlation with human behavior. We observed significant differences among polymorphisms DAT 9/9, 9/10, 10/10 in terms of proportion of particular genotypes between athletes and the control group. We also found significant differences in the NEO FFI sten scale for conscientiousness. We noticed that anxiety was related with genotypic variants of DAT1, specifically the 9/10 VNTR variant, which conditioned lower levels of anxiety in the group of tested athletes. By contrast, the lower sten value of agreeability was statistically significant for the group of athletes that were carriers of the 10/10 VNTR genotype. Heterozygous 9/10 VNTR among athletes showed lower levels of anxiety in comparison with the control group, whereas agreeability determined using the NEO FFI scale represented a lower value among athletes that had the 10/10 polymorphism. We may thus conclude that the presence of polymorphic variants of the dopamine transporter gene corresponds to athletes’ personality traits.

Abstract

Postpartum fatigue is an important issue that threatens women’s health. The incidence of postpartum fatigue is high. Failure to intervene in time may lead to adverse outcomes such as postpartum depression, premature termination of breastfeeding, child abuse, and low infant development. This article reviews the concepts, characteristics, related factors, adverse effects, and interventions of postpartum fatigue. The aim is to improve doctors’ and nurses’ awareness of on postpartum fatigue in pregnant women, enrich the research content and methods, stimulate the interest of nurses, and actively carry out targeted intervention research to prevent or reduce the occurrence of adverse outcomes.

Abstract

Anxiety is often mentioned in people’s daily life, especially in the field of medicine and psychology. For nursing, a clear understanding of anxiety is conducive to clinical nursing practice and research. Under the guidance of the Walker and Avant method, this article conducts a concept analysis of anxiety that provides a comprehensive and rounded analysis of anxiety and helps nurses gain a better understanding of anxiety.

Abstract

This study aimed to examine the interchangeability of two external training load (ETL) monitoring methods: arbitrary vs. individualized speed zones. Thirteen male outfield players from a professional soccer team were monitored during training sessions using 10-Hz GPS units over an 8-week competitive period (n = 302 observations). Low-speed activities (LSA), moderate-speed running (MSR), high-speed running (HSR) and sprinting were defined using arbitrary speed zones as <14.4, 14.4–19.8, 19.8–25.1 and ≥25.2 km·h-1, and using individualized speed zones based on a combination of maximal aerobic speed (MAS, derived from the Yo-yo Intermittent recovery test level 1), maximal sprinting speed (MSS, derived from the maximal speed reached during training) and anaerobic speed reserve (ASR) as <80% MAS, 80–100% MAS, 100% MAS or 29% ASR and ≥30% ASR. Distance covered in both arbitrary and individualized methods was almost certainly correlated in all speed zones (p < 0.01; r = 0.67-0.78). However, significant differences between methods were observed in all speed zones (p < 0.01). LSA was almost certainly higher when using the arbitrary method than when using the individualized method (p < 0.01; ES = 5.47 [5.18; 5.76], respectively). Conversely, MSR, HSR and sprinting speed were higher in the individualized method than in the arbitrary method (p < 0.01; ES = 5.10 [4.82; 5.37], 0.86 [0.72; 1.00] and 1.22 [1.08; 1.37], respectively). Arbitrary and individualized methods for ETL quantification based on speed zones showed similar sensitivity in depicting player locomotor demands. However, since these methods significantly differ at absolute level (based on measurement bias), arbitrary and individualized speed zones should not be used interchangeably.

Abstract

The aims of the study were: a) to analyze the reproducibility of the Modified Agility Test (MAT) according to two types of displacement (i.e. constrained [MATtop] vs. free [MATfree]), b) to examine the explanatory capacity of anthropometric characteristics and neuromuscular performance on the ability to change the direction (CODA), c) to look into the practical consequences of the types of displacement from the perspective of an elite soccer academy. 118 male soccer players (age: 16 (13-25) years old) from the same elite Spanish soccer academy (U13 to senior) were tested twice on two versions of the MAT (MATtop and MATfree), with 48 hours between testing sessions. Moreover, they were tested on linear-sprint performance, over 5 m (S5m) and 15 m (S15m), and the vertical jump (VJ) (countermovement jump with [ACMJ] and without an arm swing [CMJ]). The main findings were: a) the type of displacement did not affect the reliability of the CODA test; b) weight, S15m, ACMJ and CMJ variables explained close to 60% of CODA performance; c) MATtop (i.e. constrained displacement) and MATfree (i.e. free-displacement) CODA tests could show different profiles of development along the age groups; and d) the impact of the task’s constraints was relatively higher in U16 and U17 groups. CODA seems to have a variable meaning depending on the characteristics of the test and the age of the participants.

Abstract

Background

Chronic obstructive pulmonary disease (COPD) continues to cause a heavy health and economic burden in the Europe and around the world. Arterial hypertension (AH) is considered as one of the principal COPD-associated comorbidi-ties. However, no data for association between gene polymorphism and AH in patients with COPD in Ukraine have ever been internationally published. We assessed the genotype and allele frequencies of angiotensinogen (AGT) M235T polymorphisms in patients with COPD and comorbid AH.

Methods

The study group consisted of 96 patients: Group 1 (25 individuals with COPD), Group 2 (23 individuals with AH) and Group 3 (28 individuals with COPD and AH). The control group consisted of 20 healthy subjects. M/T genotypes of AGT were determined by polymerase chain reaction amplification.

Results

The results of the study have not demonstrated any significant impact of alleles of AGT genes on the occurrence of diseases such as COPD, AH and combinations thereof. However, analysis of odds ratio has demonstrated the presence of a trend towards a protective role of the M allele of the AGT gene concerning occurrence of COPD, AH and their combinations. At the same time, the presence of the T allele of the AGT gene may increase the risk for occurrence of the above-mentioned diseases.

Conclusions

The study that we have conducted suggests that the presence of T allele of the AGT gene at position 235 of the peptide chain both in homozygous and heterozygous states may increase the risk for AH in patients with COPD.