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1.
Seyed Ziyae Aldin Samsam Shariat Fatemeh Borzouee Mohammad Reza Mofid Jaleh Varshosaz 《Biotechnology letters》2018,40(9-10):1343-1353
Objectives
The purpose of this study was to develop a facile and efficient method to enhance the stability and activity of lactoperoxidase (LPO) by using its immobilization on graphene oxide nanosheets (GO-NS).Methods
Following the LPO purification from bovine whey, it was immobilized onto functionalized GO-NS using glutaraldehyde as cross-linker. Kinetic properties and stability of free and immobilized LPO were investigated.Results
LPO was purified 59.13 fold with a specific activity of 5.78 U/mg protein. The successful immobilization of LPO on functionalized GO-NS was confirmed by using dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FT-IR). The overall results showed that the stability of the immobilized LPO was considerably improved compared to free LPO. Apparent Km and Vmax of LPO also indicated that the immobilized enzyme had greater affinity to the substrate than the native enzyme.Conclusions
Graphene oxide nanosheets are effective means for immobilization of LPO.2.
Background
Few studies have examined the time-course of localized exercise training on regional blood flow in humans. The study examined the influence of handgrip exercise training on forearm reactive hyperemic blood flow and vascular resistance in apparently healthy men.Methods
Forearm blood flow and vascular resistance were evaluated, in 17 individuals [Age: 22.6 ± 3.5], in both arms, at rest and following 5 minutes of arterial occlusion, using strain gauge plethysmography, prior to training (V1) and every week thereafter (V2-5) for 4 weeks. Handgrip exercise was performed in the non-dominant arm 5 d/wk for 20 minutes at 60% of maximum voluntary contraction, while the dominant arm served as control.Results
Resting HR, BP, and forearm blood flow and vascular resistance were not altered with training. The trained arm handgrip strength and circumference increased by 14.5% (p = 0.014) and 1.56% (p = 0.03), respectively. ANOVA tests revealed an arms by visit interaction for the trained arm for reactive hyperemic blood flow (p = 0.02) and vascular resistance (p = 0.009). Post-hoc comparison demonstrated increased reactive hyperemic blood flow (p = 0.0013), and decreased post-occlusion vascular resistance (p = 0.05), following the 1st week of training, with no significant changes in subsequent visits.Conclusion
The results indicate unilateral improvements in forearm reactive hyperemic blood flow and vascular resistance following 1 week of handgrip exercise training and leveled off for the rest of the study.3.
Background
Biering-Sørenson (1984) found that individuals with less lumbar extensor muscle endurance had an increased occurrence of first episode low back pain. As a result, back endurance tests have been recommended for inclusion in health assessment protocols. However, different studies have reported markedly different values for endurance times, leading some researchers to believe that the back is receiving support from the biceps femoris and gluteus maximus. Therefore, this study was designed to examine the haemodynamic and neuromuscular activity of the erector spinae, biceps femoris, and gluteus maximus musculature during the Biering-Sørenson Muscular Endurance Test (BSME).Methods
Seventeen healthy individuals and 46 individuals with chronic low back pain performed the Biering-Sørenson Muscular Endurance Test while surface electromyography was used to quantify neuromuscular activity. Disposable silver-silver-chloride electrodes were placed in a bipolar arrangement over the right or left biceps femoris, gluteus maximus, and the lumbosacral paraspinal muscles at the level of L3. Near Infrared Spectroscopy was used simultaneously to measure tissue oxygenation and blood volume changes of the erector spinae and biceps femoris.Results
The healthy group displayed a significantly longer time to fatigue (Healthy: 168.5s, LBP: 111.1s; p ≤ 0.05). Significant differences were shown in the median frequency slope of the erector spinae between the two groups at 90–100% of the time to fatigue while no significant differences were noted in the haemodynamic data for the two groups.Conclusion
Although the BSME has been recognized as a test for back endurance, individuals with chronic LBP appear to incorporate a strategy that may help support the back musculature by utilizing the biceps femoris and gluteus maximus to a greater degree than their healthy counterparts.4.
N. Cesbron A.-L. Royer Y. Guitton A. Sydor B. Le Bizec G. Dervilly-Pinel 《Metabolomics : Official journal of the Metabolomic Society》2017,13(8):99
Introduction
Collecting feces is easy. It offers direct outcome to endogenous and microbial metabolites.Objectives
In a context of lack of consensus about fecal sample preparation, especially in animal species, we developed a robust protocol allowing untargeted LC-HRMS fingerprinting.Methods
The conditions of extraction (quantity, preparation, solvents, dilutions) were investigated in bovine feces.Results
A rapid and simple protocol involving feces extraction with methanol (1/3, M/V) followed by centrifugation and a step filtration (10 kDa) was developed.Conclusion
The workflow generated repeatable and informative fingerprints for robust metabolome characterization.5.
Background
Dynamic exercise is characterized by relaxation periods between contractions. The relaxation period should be considered as a causal factor for determining the magnitude of blood flow during dynamic exercise. The purpose of this study was to investigate the effect of muscle relaxation periods determined by the response of each subject on the exercise-induced blood flow response.Methods
Seven healthy female subjects performed dynamic plantar flexions twice in succession; the duration of each flexion was 1- s and they were performed at an intensity of 15%, 30% and 50% of the maximal voluntary contraction (MVC). Based on the blood flow response after a single contraction, we set up intervals between two successive contractions; the intervals corresponded to 50% (pre-Tpeak), 100% (Tpeak), and 150% (post-Tpeak) of the time required to reach peak blood flow.Results
In all the conditions, upon cessation of the contraction, there was a progressive, beat-by-beat increase in the blood flow through the popliteal artery that peaked by the 5th cardiac cycle. Peak values of blood flow achieved after exercise were significantly higher at pre-Tpeak than at Tpeak and post-Tpeak (p < 0.05).Conclusion
The result indicate that at three intervals based on the time taken to reach the peak value, the highest blood flow value was obtained at the pre-Tpeak interval.6.
Anlei Chen Xiaoli Xie Tida Ge Haijun Hou Wei Wang Wenxue Wei Yakov Kuzyakov 《Plant and Soil》2017,413(1-2):203-216
Aims
This study is aimed to investigate the efficiency of plant growth-promoting (PGP) strategies of Enterobacter sp. strain EG16 under metal stress and its potential application in phytoremediation.Methods
Production of siderophores and indole-3-acetic acid (IAA) by EG16 were assessed in a hydroponic system in which Hibiscus cannabinus was grown with different concentrations of Cd and Fe. A pot experiment was also carried out to evaluate the practical effect of EG16 on H. cannabinus growth and remediation efficiency.Results
Inoculation with EG16 significantly improved plant growth, probably as a result of increased plant uptake of Fe and immobilization of Cd2+, which resulted in decreased plant accumulation of Cd. Increased production of siderophores by EG16 in response to Cd exposure appeared to be the PGP strategy functioning in the EG16–H. cannabinus association. The bacterial Cd response system promoted plant and bacterial uptake of Fe, alleviated Cd-induced inhibition of bacterial IAA production, and potentially assisted in metal immobilization in the rhizosphere.Conclusions
The EG16–H. cannabinus association may be useful for phytostabilization, as it exhibits good plant growth, low plant accumulation of metals, and reduced metal bioavailability in soil.7.
Rachel A. Spicer Christoph Steinbeck 《Metabolomics : Official journal of the Metabolomic Society》2018,14(1):16
Introduction
Data sharing is being increasingly required by journals and has been heralded as a solution to the ‘replication crisis’.Objectives
(i) Review data sharing policies of journals publishing the most metabolomics papers associated with open data and (ii) compare these journals’ policies to those that publish the most metabolomics papers.Methods
A PubMed search was used to identify metabolomics papers. Metabolomics data repositories were manually searched for linked publications.Results
Journals that support data sharing are not necessarily those with the most papers associated to open metabolomics data.Conclusion
Further efforts are required to improve data sharing in metabolomics.8.
Angela Lombardi Bruno Trimarco Guido Iaccarino Gaetano Santulli 《Cell communication and signaling : CCS》2017,15(1):47
Background
One of the most common side effects of the immunosuppressive drug tacrolimus (FK506) is the increased risk of new-onset diabetes mellitus. However, the molecular mechanisms underlying this association have not been fully clarified.Methods
We studied the effects of the therapeutic dose of tacrolimus on mitochondrial fitness in beta-cells.Results
We demonstrate that tacrolimus impairs glucose-stimulated insulin secretion (GSIS) in beta-cells through a previously unidentified mechanism. Indeed, tacrolimus causes a decrease in mitochondrial Ca2+ uptake, accompanied by altered mitochondrial respiration and reduced ATP production, eventually leading to impaired GSIS.Conclusion
Our observations individuate a new fundamental mechanism responsible for the augmented incidence of diabetes following tacrolimus treatment. Indeed, this drug alters Ca2+ fluxes in mitochondria, thereby compromising metabolism-secretion coupling in beta-cells.9.
Background
In this study, we optimized the process for enhancing amylase production from Pseudomonas balearica VITPS19 isolated from agricultural lands in Kolathur, India.Methods
Process optimization for enhancing amylase production from the isolate was carried out by Response Surface Methodology (RSM) with optimized chemical and physical sources using Design expert v.7.0. A central composite design was used to evaluate the interaction between parameters. Interaction between four factors–maltose (C-source), malt extract (Nsource), pH, and CaCl2 was studied.Results
The factors pH and CaCl2 concentration were found to affect amylase production. Validation of the experiment showed a nearly twofold increase in alpha amylase production.Conclusion
Amylase production was thus optimized and increased yield was achieved.10.
Background
In recent years the visualization of biomagnetic measurement data by so-called pseudo current density maps or Hosaka-Cohen (HC) transformations became popular.Methods
The physical basis of these intuitive maps is clarified by means of analytically solvable problems.Results
Examples in magnetocardiography, magnetoencephalography and magnetoneurography demonstrate the usefulness of this method.Conclusion
Hardware realizations of the HC-transformation and some similar transformations are discussed which could advantageously support cross-platform comparability of biomagnetic measurements.11.
Background
An influenza H3N2 epidemic occurred throughout Southern China in 2012.Methods
We analyzed the hemagglutinin (HA) and neuraminidase (NA) genes of influenza H3N2 strains isolated between 2011–2012 from Guangdong. Mutation sites, evolutionary selection, antigenic sites, and N-glycosylation within these strains were analyzed.Results
The 2011–2012 Guangdong strains contained the HA-A214S, HA-V239I, HA-N328S, NA-L81P, and NA-D93G mutations, similar to those seen in the A/ Perth/16/2009 influenza strain. The HA-NSS061–063 and NNS160–162 glycosylation sites were prevalent among the 2011–2012 Guangdong strains but the NA-NRS402–404 site was deleted. Antigenically, there was a four-fold difference between A/Perth/16/2009 -like strains and the 2011–2012 Guangdong strains.Conclusion
Antigenic drift of the H3N2 subtype contributed to the occurrence of the Southern China influenza epidemic of 2012.12.
Jamie V. de Seymour Stephanie Tu Xiaoling He Hua Zhang Ting-Li Han Philip N. Baker Karolina Sulek 《Metabolomics : Official journal of the Metabolomic Society》2018,14(6):79
Introduction
Intrahepatic cholestasis of pregnancy (ICP) is a common maternal liver disease; development can result in devastating consequences, including sudden fetal death and stillbirth. Currently, recognition of ICP only occurs following onset of clinical symptoms.Objective
Investigate the maternal hair metabolome for predictive biomarkers of ICP.Methods
The maternal hair metabolome (gestational age of sampling between 17 and 41 weeks) of 38 Chinese women with ICP and 46 pregnant controls was analysed using gas chromatography–mass spectrometry.Results
Of 105 metabolites detected in hair, none were significantly associated with ICP.Conclusion
Hair samples represent accumulative environmental exposure over time. Samples collected at the onset of ICP did not reveal any metabolic shifts, suggesting rapid development of the disease.13.
Renato de Souza Pinto Lemgruber Kaspar Valgepea Mark P. Hodson Ryan Tappel Sean D. Simpson Michael Köpke Lars K. Nielsen Esteban Marcellin 《Metabolomics : Official journal of the Metabolomic Society》2018,14(3):35
Introduction
Quantification of tetrahydrofolates (THFs), important metabolites in the Wood–Ljungdahl pathway (WLP) of acetogens, is challenging given their sensitivity to oxygen.Objective
To develop a simple anaerobic protocol to enable reliable THFs quantification from bioreactors.Methods
Anaerobic cultures were mixed with anaerobic acetonitrile for extraction. Targeted LC–MS/MS was used for quantification.Results
Tetrahydrofolates can only be quantified if sampled anaerobically. THF levels showed a strong correlation to acetyl-CoA, the end product of the WLP.Conclusion
Our method is useful for relative quantification of THFs across different growth conditions. Absolute quantification of THFs requires the use of labelled standards.14.
Hiroaki Sakamoto Tomohiro Komatsu Koji Yamasaki Takenori Satomura Shin-ichiro Suye 《Biotechnology letters》2017,39(2):235-240
Objectives
To design and construct a novel bio-anode electrode based on the oxidation of glutamic acid to produce 2-oxoglutarate, generating two electrons from NADH.Results
Efficient enzyme reaction and electron transfer were observed owing to immobilization of the two enzymes using a mixed self-assembled monolayer. The ratio of the immobilized enzymes was an important factor affecting the efficiency of the system; thus, we quantified the amounts of immobilized enzyme using a quartz crystal microbalance to further evaluate the electrochemical reaction. The electrochemical reaction proceeded efficiently when approximately equimolar amounts of the enzyme were on the electrode. The largest oxidation peak current increase (171 nA) was observed under these conditions.Conclusion
Efficient multi-enzyme reaction on the electrode surface has been achieved which is applicable for biofuel cell application.15.
Gabriella Saviano Debora Paris Dominique Melck Antonio Falasca Dalila Trupiano Maria Iorizzi Gabriella S. Scippa Andrea Motta 《Metabolomics : Official journal of the Metabolomic Society》2016,12(4):65
Introduction
Molecular factors are differentially observed in various bent sectors of poplar (Populus nigra) woody taproots. Responses to stress are modulated by a complex interplay among different hormones and signal transduction pathways. In recent years, metabolomics has been recognized as a powerful tool to characterize metabolic network regulation, and it has been widely applied to investigate plant responses to biotic and abiotic stresses.Objectives
In this paper we used metabolomics to understand if long term-bending stress induces a “spatial” and a “temporal” metabolic reprogramming in woody poplar roots.Methods
By NMR spectroscopy and statistical analysis we investigated the unstressed and three portions of stressed root (above-bent, bent, and below-bent) sectors collected at 12 (T0), 13 (T1) and 14 (T2) months after stress induction.Results
The data indicate a clear between-class separation of control and stressed regions, based on the metabolites regulation, during both spatial and temporal changes. We found that taproots, as a consequence of the stress, try to restore homeostasis and normal metabolic fluxes thorough the synthesis and/or accumulation of specific compounds related to mechanical forces distribution along the bent taproot.Conclusion
The data demonstrate that the impact of mechanical stress on plant biology can efficiently be studied by NMR-based metabolomics.16.
Yan Ru Wu Yun Gyeong Kang Ji Won Shin Mi Jin Kim Jung-Woog Shin 《Biotechnology letters》2017,39(8):1121-1127
Objective
To control the oscillatory behavior of the intracellular calcium ([Ca2+]i) concentration in endothelial cells via mechanical factors (i.e., various hydrostatic pressures) because [Ca2+]i in these cells is affected by blood pressure.Results
Quantitative analyses based on real-time imaging showed that [Ca2+]i oscillation frequency and relative concentration increased significantly when 200 mm Hg pressure, mimicking hypertension, was applied for >10 min. Peak height and peak width decreased significantly at 200 mm Hg. These trends were more marked as the duration of the 200 mm Hg pressure was increased. However, no change was observed under normal blood pressure conditions 100 mm Hg.Conclusion
We generated a simple in vitro model to study [Ca2+]i behavior in relation to various pathologies and diseases by eliminating possible complicating effects induced by chemical cues.17.
A. E. Rigamonti M. Haenelt M. Bidlingmaier A. De Col S. Tamini G. Tringali R. De Micheli L. Abbruzzese C. R. Goncalves da Cruz M. Bernardo-Filho S. G. Cella A. Sartorio 《BMC endocrine disorders》2018,18(1):96
Background
Growth hormone (GH) is a heterogeneous protein composed of several molecular isoforms, the most abundant ones being the 22?kDa- and 20?kDa-GH. Exercise-induced secretion of GH isoforms has been extensively investigated in normal-weight individuals due to antidoping purposes, particularly recombinant human GH (rhGH) abuse. On the other hand, the evaluation of exercise-induced responses in GH isoforms has never been performed in obese subjects.Methods
The acute effects of whole body vibration (WBV) or maximal voluntary contraction (MVC) alone and the combination of MVC with WBV (MVC?+?WBV) on circulating levels of 22?kDa- and 20?kDa-GH were evaluated in 8 obese male adolescents [mean age?±?SD: 17.1?±?3.3?yrs.; weight: 107.4?±?17.8?kg; body mass index (BMI): 36.5?±?6.6?kg/m2; BMI standard deviation score (SDS): 3.1?±?0.6].Results
MVC (alone or combined with WBV) significantly stimulated 22?kDa- and 20?kDa-GH secretion, while WBV alone was ineffective. In particular, 22?kDa- and 20?kDa-GH peaks were significantly higher after MVC?+?WBV and MVC than WBV. In addition, 22?kDa-GH (but not 20?kDa-GH) peak was significantly higher after MVC?+?WBV than MVC. Importantly, the ratio of circulating levels of 22?kDa- to 20?kDa-GH was constant throughout the time window of evaluation after exercise and similar among the three different protocols of exercise.Conclusions
The results of the present study confirm the ability of MVC, alone and in combination with WBV, to stimulate both 22?kDa- and 20?kDa-GH secretion in obese patients, these responses being related to the exercise workload. Since the ratio of 22?kDa- to 20?kDa-GH is constant after exercise and independent from the protocols of exercise as in normal-weight subjects, hyposomatotropism in obesity does not seem to depend on an unbalance of circulating GH isoforms. Since the present study was carried out in a small cohort of obese sedentary adolescents, these preliminary results should be confirmed in further future studies enrolling overweight/obese subjects with a wider age range.18.
Objective
To fabricate an active and stable enzyme through covalent immobilization, a Ubl-specific protease (Ulp1) was used to cleave small ubiquitin-like modifier (SUMO) fusion proteins.Results
We immobilized Ulp1 on N-hydroxysuccinimide (NHS)-activated Sepharose with a coupling efficiency of 1.7 mg/ml. The immobilized Ulp1 maintains 95% substrate-cleavage ability and significantly enhances pH and thermal stability, especially can withstand pH of 10.5. Besides resistance against some small molecules, the immobilized Ulp1 can tolerate 15% (v/v) DMSO and 20% (v/v) ethanol. It can be reused for more than 15 batch reactions with 90% activity retention. This provides a fast purification system to quickly obtain cleaved recombinant proteins with 95% purity from cell lysates with the application of immobilized Ulp1.Conclusions
Ulp1 used in immobilization form is a potentially useful tool for cleavage of SUMO-tagged proteins and may reduce time and cost of protein purification.19.
Introduction
Untargeted metabolomics is a powerful tool for biological discoveries. To analyze the complex raw data, significant advances in computational approaches have been made, yet it is not clear how exhaustive and reliable the data analysis results are.Objectives
Assessment of the quality of raw data processing in untargeted metabolomics.Methods
Five published untargeted metabolomics studies, were reanalyzed.Results
Omissions of at least 50 relevant compounds from the original results as well as examples of representative mistakes were reported for each study.Conclusion
Incomplete raw data processing shows unexplored potential of current and legacy data.20.
Nadine Strehmel David Strunk Veronika Strehmel 《Metabolomics : Official journal of the Metabolomic Society》2017,13(11):135