Beneficial effects of empagliflozin on hematocrit levels in a patient with severe anemia

IntroductionSodium-glucose cotransporter (SGLT2) inhibitors may additionally benefit patients with diabetes by improving their erythropoiesis followed by the elevation of hemoglobin and hematocrit levels.Reason for the reportIn the case described, severe normocytic normochromic anemia was resolved when empagliflozin had been introduced to the therapy.Case summaryA 78-year-old male patient was admitted to our hospital with a non-ST-segment elevation myocardial infarction. His past medical history included diabetes, right coronary artery angioplasty, myocardial infarction and paroxysmal atrial fibrillation which required anticoagulant treatment. When examined, severe normocytic normochromic anemia was also diagnosed. About two years prior to his admission, the patient began suffering from persistent anemia despite the modification of his anticoagulant therapy with warfarin, rivaroxaban and dabigatran. An extensive evaluation failed to provide an explanation for his anemia.OutcomeEventually, only the introduction of empagliflozin successfully increased the values of hemoglobin and hematocrit. Therefore, it transpires that SGLT2 enhances erythropoietin (EPO) secretion which subsequently raises hematocrit levels in patients with severe anemia.Graphic abstract      

Comparison between the Original- and a Standardized Version of a Physical Assessment Test for the Dorsal Chain - A Cohort-Based Cross Sectional Study

This cohort-based cross-sectional study compares the original (OV) and a newly developed standardized version (SV) of the Bunkie Test, a physical test used to assess the dorsal chain muscles. Twenty-three participants (13 females, 10 males; median age of 26 ± 3 years) performed the test, a reverse plank, with one foot on a stool and the contralateral leg lifted. In the SV, the position of the pelvis and the foot were predefined. The test performance time (s) and surface electromyography (sEMG) signals of the dorsal chain muscles were recorded. We performed a median power frequency (MPF) analysis, using short-time Fourier transformation, and calculated the MPF/time linear regression slope. We compared the slopes of the linear regression analysis (between legs) and the performance times (between the OV and SV) with the Wilcoxon test. Performance times did not differ between SV and OV for either the dominant (p = 0.28) or non-dominant leg (p = 0.08). Linear regression analysis revealed a negative slope for the muscles of the tested leg and contralateral erector spinae, with a significant difference between the biceps femoris of the tested (-0.91 ± 1.08) and contralateral leg (0.01 ± 1.62) in the SV (p = 0.004). The sEMG showed a clearer pattern in the SV than in the OV. Hence, we recommend using the SV to assess the structures of the dorsal chain of the tested leg and contralateral back. Key points

• The standardized Bunkie Test assesses the dorsal chain muscles.
• It targets mainly the muscles of the tested leg and the contralateral lower back.
• In contrast, for the original test version the surface electromyography results were inconsistent.
• For consistent, standardized results, we recommend standardizing the foot and pelvis position precisely during the test.

Key words: Bunkie Test, musculoskeletal diagnostics, physical performance test, myofascial system, superficial backline, surface electromyography     

Combined phospholamban ablation and SERCA1a overexpression result in a new hyperdynamic cardiac state

OBJECTIVE: Phospholamban ablation or ectopic expression of SERCA1a in the heart results in significant increases in cardiac contractile parameters. The aim of the present study was to determine whether a combination of these two genetic manipulations may lead to further augmentation of cardiac function. METHODS: Transgenic mice with cardiac specific overexpression of SERCA1a were mated with phospholamban deficient mice to generate a model with SERCA1a overexpression in the phospholamban null background (SERCA1(OE)/PLB(KO)). The cardiac phenotype was characterized using quantitative immunoblotting, sarcoplasmic reticulum calcium uptake and single myocyte mechanics and calcium kinetics. RESULTS: Quantitative immunoblotting revealed an increase of 1.8-fold in total SERCA level, while SERCA2 was decreased to 50% of wild types. Isolated myocytes indicated increases in the maximal rates of contraction by 195 and 125%, the maximal rates of relaxation by 200 and 124%, while the time for 80% decay of the Ca(2+)-transient was decreased to 43 and 75%, in SERCA1(OE)/PLB(KO) hearts, compared to SERCA1a overexpressors and phospholamban knockouts, respectively. These mechanical alterations reflected parallel alterations in V(max) and EC(50) for Ca(2+) of the sarcoplasmic reticulum Ca(2+) transport system. Furthermore, there were no significant cardiac histological or pathological alterations, and the myocyte contractile parameters remained enhanced, up to 12 months of age. CONCLUSIONS: These findings suggest that a combination of SERCA1a overexpression and phospholamban ablation results in further enhancement of myocyte contractility over each individual alteration.     

Bone marrow cells adopt the cardiomyogenic fate in vivo

The possibility that adult bone marrow cells (BMCs) retain a remarkable degree of developmental plasticity and acquire the cardiomyocyte lineage after infarction has been challenged, and the notion of BMC transdifferentiation has been questioned. The center of the controversy is the lack of unequivocal evidence in favor of myocardial regeneration by the injection of BMCs in the infarcted heart. Because of the interest in cell-based therapy for heart failure, several approaches including gene reporter assay, genetic tagging, cell genotyping, PCR-based detection of donor genes, and direct immunofluorescence with quantum dots were used to prove or disprove BMC transdifferentiation. Our results indicate that BMCs engraft, survive, and grow within the spared myocardium after infarction by forming junctional complexes with resident myocytes. BMCs and myocytes express at their interface connexin 43 and N-cadherin, and this interaction may be critical for BMCs to adopt the cardiomyogenic fate. With time, a large number of myocytes and coronary vessels are generated. Myocytes show a diploid DNA content and carry, at most, two sex chromosomes. Old and new myocytes show synchronicity in calcium transients, providing strong evidence in favor of the functional coupling of these two cell populations. Thus, BMCs transdifferentiate and acquire the cardiomyogenic and vascular phenotypes restoring the infarcted heart. Together, our studies reveal that locally delivered BMCs generate de novo myocardium composed of integrated cardiomyocytes and coronary vessels. This process occurs independently of cell fusion and ameliorates structurally and functionally the outcome of the heart after infarction.     

Al2O3-Cu-Ni Composites Manufactured via Uniaxial Pressing: Microstructure,Magnetic, and Mechanical Properties

This study’s main goal was to obtain and characterize Al₂O₃-Cu-Ni composites with different metallic phase content. The study analyzed the three series of samples differing in the metallic phase 5, 10, 15 vol.% volume contents. An identical volume share of the metallic components in the metallic phase was used. Ceramic–metal composites were formed using uniaxial pressing and sintered at a temperature of 1400 °C. The microstructural investigation of the Al₂O₃-Cu-Ni composite and its properties involved scanning electron microscopes observations and X-ray diffraction. The size of the metallic phase in the ceramic matrix was performed using a stereological analysis. Microhardness analysis with fracture toughness measures was applied to estimate the mechanical properties of the prepared materials. Additionally, magnetic measurements were carried out, and the saturation magnetization was determined on the obtained magnetic hysteresis loops. The prepared samples, regardless of the content of the metallic phase in each series, were characterized by a density exceeding 95% of the theoretical density. The magnetic measurements exhibited that the fabricated composites had ferromagnetic properties due to nickel and nickel-rich phases. The hardness of the samples containing 5, 10, 15 vol.% metallic phases decreased with an increase in the metallic phase content, equal to 17.60 ± 0.96 GPa, 15.40 ± 0.81 GPa, 12.6 ± 0.36 GPa, respectively.     

The influence of single and binary mixtures of collagen amino acids on the structure of synthetic calcium hydroxyapatite as a nanobiomaterial

The modifications carried out as part of this study were aimed at examining the effect of the addition of collagen amino acids: glycine, proline and hydroxyproline (used separately and in binary mixtures) on the physicochemical properties of hydroxyapatite obtained in their presence in vitro. The influence of mixtures of amino acids on these properties is an important element of scientific novelty. The obtained samples were tested with the use of instrumental methods: FT-IR, TEM, EDXMA, PXRD and UV spectrophotometry. The results showed the influence of the amino acids used on changes in the relative content of the labile phosphate groups constituting the structure of the hydrated surface layer of crystals. As a consequence, there were differences in some physicochemical properties of the obtained hydroxyapatites (degree of crystallinity, molar Ca/P ratio). It was also determined how the ability of the used amino acids to bind to hydroxyapatite changes.

The influence of mixtures of collagen amino acids on hydroxyapatite has been determined. Glycine has the strongest effect on hydroxyapatite, and proline the weakest. Proline abolishes the effect of other amino acids on hydroxyapatite.     

Comparison of the Prolonged Effects of Foam Rolling and Vibration Foam Rolling Interventions on Passive Properties of Knee Extensors

Foam rolling (FR) and vibration foam rolling (VFR) interventions have received attention as pre-exercise warm-ups because they maintain performance and increase range of motion (ROM). However, the immediate and prolonged effects and the comparisons between FR and VFR interventions are unknown. Therefore, this study was designed to compare the effects of FR and VFR interventions on passive properties of knee extensors over time (up to 30 min after interventions). A crossover, random allocation design was used with 14 male college students (22.1 ± 1.0 years old) in the control, FR, and VFR conditions. The knee flexion ROM, pain pressure threshold (PPT), and tissue hardness were measured before and immediately after, 10, 20, and 30 minutes after the intervention. The results showed that knee flexion ROM increased significantly immediately after the intervention in both the FR and VFR conditions and maintained up to 30 minutes after both conditions. PPT increased significantly (p < 0.01) immediately after the FR intervention. In the VFR condition, there was a significant increase in PPT immediately after the intervention (p < 0.01) and 10 minutes after the intervention (p < 0.05). Tissue hardness was significantly decreased (p < 0.01) immediately after and 10 minutes after the FR intervention. However, tissue hardness in the VFR condition was significantly decreased (p < 0.01) up to 30 minutes after the intervention. The results suggest that FR and VFR interventions increase knee flexion ROM, and the effect lasts at least 30 minutes, but the effects on PPT and tissue hardness are maintained a longer time in the VFR condition compared to the FR condition. Therefore, VFR can be recommended as a warm-up before exercise to change the passive properties of knee extensors. Key points

• We investigated the sustained effects of foam rolling (FR) and vibration foam rolling (VFR) interventions on knee flexion range of motion (ROM), pain pressure threshold, and tissue hardness.
• FR and VFR intervention for 180 seconds increased ROM for at least up to 30 minutes.
• The changes in pain pressure threshold and tissue hardness after VFR intervention were sustained for a longer duration rather than FR intervention.
• VFR intervention could be recommended in sports and rehabilitation settings to increase ROM by changing the pain pressure threshold and tissue hardness.

Key words: Range of motion, warm-up routine, pain pressure threshold, tissue hardness     

Influence of the AlSi7Mg0.6 Aluminium Alloy Powder Reuse on the Quality and Mechanical Properties of LPBF Samples

Additive manufacturing (AM) is dynamically developing and finding applications in different industries. The quality of input material is a part of the process and of the final product quality. That is why understanding the influence of powder reuse on the properties of bulk specimens is crucial for ensuring the repeatable AM process chain. The presented study investigated the possibility of continuous reuse of AlSi7Mg0.6 powder in the laser powder bed fusion process (LPBF). To date, there is no study of AlSi7Mg0.6 powder reuse in the LPBF process to be found in the literature. This study aims to respond to this gap. The five batches of AlSi7Mg0.6 powder and five bulk LPBF samples series were characterised using different techniques. The following characteristics of powders were analysed: the powder size distribution (PSD), the morphology (scanning electron microscopy—SEM), the flowability (rotating drum analysis), and laser light absorption (spectrophotometry). Bulk samples were characterised for microstructure (SEM), chemical composition (X-ray fluorescence spectrometry—XRF), porosity (computed tomography—CT) and mechanical properties (tensile, hardness). The powder was reused in subsequent processes without adding (recycling/rejuvenation) virgin powder (collective ageing powder reuse strategy). All tested powders (powders P0–P4) and bulk samples (series S0–S3) show repeatable properties, with changes observed within error limits. Samples manufactured within the fifth reuse cycle (series S4) showed some mean value changes of measured characteristics indicating initial degradation. However, these changes also mostly fit within error limits. Therefore, the collective ageing powder reuse strategy is considered to give repeatable LPBF process results and is recommended for the AlSi7Mg0.6 alloy within at least five consecutive LPBF processes.