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1.
Pierre-Jean Saulnier Manjula Darshi Kevin M. Wheelock Helen C. Looker Gudeta D. Fufaa William C. Knowler E. Jennifer Weil Stephanie K. Tanamas Kevin V. Lemley Rintaro Saito Loki Natarajan Robert G. Nelson Kumar Sharma 《Metabolomics : Official journal of the Metabolomic Society》2018,14(6):84
Introduction
Little is known about the association of urine metabolites with structural lesions in persons with diabetes.Objectives
We examined the relationship between 12 urine metabolites and kidney structure in American Indians with type 2 diabetes.Methods
Data were from a 6-year clinical trial that assessed renoprotective efficacy of losartan, and included a kidney biopsy at the end of the treatment period. Metabolites were measured in urine samples collected within a median of 6.5 months before the research biopsy. Associations of the creatinine-adjusted urine metabolites with kidney structural variables were examined by Pearson’s correlations and multivariable linear regression after adjustment for age, sex, diabetes duration, hemoglobin A1c, mean arterial pressure, glomerular filtration rate (iothalamate), and losartan treatment.Results
Participants (n?=?62, mean age 45?±?10 years) had mean?±?standard deviation glomerular filtration rate of 137?±?50 ml/min and median (interquartile range) urine albumin:creatinine ratio of 34 (14–85) mg/g near the time of the biopsy. Urine aconitic and glycolic acids correlated positively with glomerular filtration surface density (partial r?=?0.29, P?=?0.030 and r?=?0.50, P?<?0.001) and total filtration surface per glomerulus (partial r?=?0.32, P?=?0.019 and r?=?0.43, P?=?0.001). 2-ethyl 3-OH propionate correlated positively with the percentage of fenestrated endothelium (partial r?=?0.32, P?=?0.019). Citric acid correlated negatively with mesangial fractional volume (partial r=-0.36, P?=?0.007), and homovanillic acid correlated negatively with podocyte foot process width (partial r=-0.31, P?=?0.022).Conclusions
Alterations of urine metabolites may associate with early glomerular lesions in diabetic kidney disease.2.
Jun Zhou Hongyang Sun Jipeng Wang Qingqing He Haijian Bing Yanhong Wu 《Plant and Soil》2018,425(1-2):1-19
Aims
We examined novel ways of non-destructively measuring root weight, plant growth and water use efficiencies to improve the detection of treatment effects in plant phenotyping in pot culture.Method
Two genotypes each of maize, sunflower and soybean were grown in 4 L ANOVApot®s in the Twinpot Water Management System (TWMS) of a constant water table. Measurement of pot weights and pot water losses (weekly and by drip rate) over time allowed the derivation of plant biomass gain and Water Use Efficiences (WUE). The destructive harvest at 31 days provided weights of plant parts and derived estimates of fresh root weight without physical recovery.Results
Derived estimates of whole plant biomass were highly correlated with harvested whole plant dry weights (r?=?0.97) and fresh shoot weights (r?=?0.99), while estimates of non-recovered fresh root weights were highly correlated with harvested shoot fresh weights (r?=?0.86) and recovered root fresh weights (r?=?0.85). WUEs based on actual water loss and drop counts varied significantly across species and between maize cultivars.Conclusions
Constant water table plant culture in pots allows measures of roots without physical recovery, in situ crop growth and WUEs based on water losses and drip rates.3.
Objectives
To establish a method for microbial transglutaminase (mTG)-mediated PEGylation of proteins at the level of lysine (Lys) residues.Results
Carboxybenzyl-glutaminyl–glycinyl-methoxypolyethylene glycol (CBZ-QG-mPEG) was prepared by introducing carboxybenzyl-glutaminyl-glycine (CBZ-QG) to mPEG amine. The analysis by Fourier transform infrared spectroscopy and SDS-PAGE showed that CBZ-QG-mPEG was successfully synthesized and can be recognized by mTG as an acyl donor to modify therapeutic protein, cytochrome c (cyt c). Finally, under an optimized condition (cyt c 0.5 mg/ml, CBZ-QG-mPEG 11.25 mg/ml, mTG 0.5 mg/ml, 37 °C, 2 h), the PEGylation yield reached 76.5 %.Conclusions
This is the first study regarding the PEGylation of protein at the level of Lys residues catalyzed by mTG. The novel method could be employed to immobilize active proteins and modify therapeutic proteins.4.
Aims
The capacitance method offers a rapid and non-destructive method for root measurement. We tested a four terminal (4 T) capacitance (C, Farads) measurement circuit, which removes parasitic errors. We also tested the plausibility of Dalton Model’s assumptions that roots act as cylindrical capacitors and that their entire length contributes to measured C.Methods
Faba bean (Vicia faba) was grown in sand and harvested at different ages to determine fresh root mass. Length and radii were determined using scanning software. Tissue density ρ was determined from observing buoyancy in water and from scanned dimensions. Relative permittivity ε r was calculated using an empirical model fitted to the data.Results
Parasitic errors were small. C was a poor predictor of root dimensions. An empirical model L ∝?(C/ρ k )m, was a reasonable predictor (R2?=?0.56; P?<?0.05) of root length L and was not related to root allometry. This relation also allowed calculation of a plausible average value of ε r .Conclusions
The well-watered conditions ensured that contact resistances were low. It appeared that the entire root system was contributing to measured C and average calculated ε r was plausible for cortex tissue, if roots were assumed to be cylindrical capacitors (i.e. the Dalton Model)5.
Objective
To improve the production of trans-10,cis-12-conjugated linoleic acid (t10,c12-CLA) from linoleic acid in recombinant Yarrowia lipolytica.Results
Cells of the yeast were permeabilized by freeze/thawing. The optimal conditions for t10,c12-CLA production by the permeabilized cells were at 28 °C, pH 7, 200 rpm with 1.5 g sodium acetate l?1, 100 g wet cells l?1, and 25 g LA l?1. Under these conditions, the permeabilized cells produced 15.6 g t10,c12-CLA l?1 after 40 h, with a conversion yield of 62 %. The permeabilized cells could be used repeatedly for three cycles, with the t10,c12-CLA extracellular production remaining above 10 g l?1.Conclusion
Synthesis of t10,c12-CLA was achieved using a novel method, and the production reported in this work is the highest value reported to date.6.
Masazumi Ando Hideaki Amayasu Takahiro Itai Hisahiro Yoshida 《BioPsychoSocial medicine》2017,11(1):19
Background
Administration of valproic acid (VPA) is complicated with approximately 0.9% of patients developing hyperammonemia, but the pathogenesis of this adverse effect remains to be clarified. The aim of the present study was to search for mechanisms associated with VPA-induced hyperammonemia in the light of changes in serum amino acids concentrations associated with the urea cycle of schizophrenic patients.Method
Blood samples (10 mL) were obtained from 37 schizophrenic patients receiving VPA for the prevention of violent behaviors in the morning after overnight fast. Blood concentrations of ammonia, VPA, free carnitine, acyl-carnitine, and 40 amino acids including glutamate and citrulline were measured for each patient. Univariate and multivariate regression analyses were performed to identify amino acids or concomitantly administered drugs that were associated with variability in the blood concentrations of ammonia.Result
The blood ammonia level was positively correlated with the serum glutamate concentration (r = 0.44, p < 0.01) but negatively correlated with glutamine (r = ?0.41, p = 0.01), citrulline (r = ?0.42, p = 0.01), and glycine concentrations (r = ?0.54, p < 0.01). It was also revealed that the concomitant administration of the mood stabilizers (p = 0.04) risperidone (p = 0.03) and blonanserin (p < 0.01) was positively associated with the elevation of the blood ammonia level.Conclusion
We hypothisized that VPA would elevate the blood ammonia level of schizophrenic patients. The observed changes in serum amino acids are compatible with urea cycle dysfunction, possibly due to reduced carbamoyl-phosphate synthase 1 (CPS1) activity. We conclude that VPA should be prudently prescribed to schizophrenic patients, particularly those receiving mood stabilizers or certain antipsychotics.7.
Zahraa Alsafi Andreas Malmgren Petri Gudmundsson Martin Stagmo Magnus Dencker 《Cardiovascular ultrasound》2017,15(1):20
Background
Long-term intensive training leads to morphological and mechanical changes in the heart generally known as “athlete’s heart”. Previous studies have suggested that the diastolic and systolic function of the ventricles is unaltered in athletes compared to sedentary.The purpose of this study was to investigate myocardial performance index (MPI) by pulsed wave Doppler (PWD) and by tissue Doppler imaging (TDI) in female elite athletes compared to sedentary controls.Methods
The study consisted of 32 athletes (mean age 20 ± 2 years) and 34 sedentary controls (mean age 23 ± 2 years). MPI by PWD and TDI were measured in the left (LV) and right ventricle (RV) in both groups. Moreover, comparisons of MPI by the two methods and between the LV and RV within the two groups were made.Results
There were no significant differences in MPI between athletes and controls (p > 0.05), whereas the LV had significantly higher MPI compared to RV (p < 0.001, in athletes and controls). The agreement and the correlation between the two methods measuring MPI showed low agreement and no correlation (athletes RV r = ?0.027, LV r = 0.12; controls RV r = 0.20, LV r = 0.30).Conclusion
The global function of the LV and RV measured by MPI with PWD and TDI is similar in female athletes compared to sedentary controls. Conversely, both MPI by PWD and by TDI shows a significant difference between the LV and RV. However, the agreement and correlation between conventional methods of measuring MPI by PWD compared to MPI by TDI is very poor in both these populations.8.
Potential effects of warming on soil respiration and carbon sequestration in a subtropical forest 总被引:1,自引:0,他引:1
Aims
Subtropical ecosystems are receiving unprecedented changes in temperature as a consequence of anthropogenic activities, which potentially affects soil respiration (R s) and carbon (C) sequestration. Due to the large amounts of C store and cycle in subtropical forests, investigations about how R s and C sequestration respond to warming will be critical for our understanding of future global-scale climate and biogeochemical cycling.Methods
In this study, we transferred soil samples and plant seedlings collected from a mixed forest to the growth chambers in two sites (300 m and 30 m a.s.l.), which induced an artificial warming of ca. 1 °C between the two corresponding forest mesocosms. We tested whether the modification of abiotic factors induced by the downward translocation could alter R s and soil C sequestration. We also investigated the effects on the biotic factors by including root biomass and soil microbial biomass.Results
Our results showed that R s was greater in the warm site than in the control site, which were related to the higher aboveground biomass, litterfall and root biomass. R s showed a significantly positive exponential relationship with soil temperature. The downward translocation tended to decrease soil C sequestration, which was attributed to the decreased C use efficiency of soil microorganisms and increased root growth under downward translocation.Conclusion
R s responded strongly to downward translocation, suggesting that climate warming exacerbated R s and tended to reduce soil C sequestration. The ability of subtropical forests to act as CO2 sink may be reduced under climate warming.9.
Heidi A. Waddell Richard J. Simpson Megan H. Ryan Hans Lambers Denys L. Garden Alan E. Richardson 《Plant and Soil》2017,412(1-2):7-19
Aims
Rytidosperma species are native Australian grasses which have different growth rates and phosphorus (P) requirements. This study examined the role of root morphology traits in response to P supply.Methods
Nine Rytidosperma species ranging from slow- to fast-growth were examined along with Lolium perenne and Bromus hordeaceus. Plants were grown in a glasshouse for 47 days in soil supplied with six levels of P between 0 and 60 mg P per pot. Root mass, length and diameter, root hair length and density, and extent of mycorrhizal colonisation were measured.Results
Across all species there was a positive correlation (P < 0.001) between P uptake and root mass, length and root hair cylinder volume (RHCV; estimated using root diameter, root hair length and root length) at all levels of P supply. An exception was the RHCV of B. hordeaceus, where expected P uptake was not achieved due to a markedly reduced root length at low-P supply. For the Rytidosperma species, morphological plasticity for specific root length, root mass fraction and root hair length ranged from 1.5-fold to 2.7-fold between high- and low-P supply. However, across all species and P levels no single root morphological trait was identified for universally increasing the size of the root system and P uptake.Conclusions
Fast-growing species took up more P as a result of an overall larger root mass, greater root length and larger RHCV.10.
Oliver Bühler Morten Ingerslev Simon Skov Erik Schou Iben Margrete Thomsen Christian Nørgaard Nielsen Palle Kristoffersen 《Plant and Soil》2017,413(1-2):29-44
Aims
The purpose of this study is to evaluate root and stem growth, nutrient status and soil properties of a tree planting in structural soil.Methods
Root and stem growth were measured at an 10-year-old urban planting of Tilia x europaea L. ‘Pallida’ established in structural soil on a paved square in Copenhagen, Denmark.Root abundance was quantified and soil profiles were established at three different distances from 10 trees (1.0, 1.9, and 2.9 m). Soil and leaf samples were analysed for nutrient concentrations.Results
Abundant root presence was measured across the entire profile of structural soil (160?×?60 cm) at all distances, provided that structural soil layers were constructed correctly. Erroneously constructed structural soil layers however, resulted in impaired tree and root growth. Coarse root morphology was affected by the confined growing space in the voids of the stone matrix. The soil was relatively alkaline with an average pH (CaCl2) of 7.3. Foliar analysis revealed deficiencies of K and Mn. These deficiencies might be due to a combined effect of high pH and low soil concentrations of these nutrients.Conclusions
The study documents that correctly constructed structural soils allow and encourage root growth in load bearing layers.11.
Objectives
To characterize a novel feruloyl esterase from Escherichia coli BL21 DE3.Results
The gene encoding BioH was cloned and overexpressed in E. coli. The protein was purified and its catalytic activity was assessed. BioH exhibited feruloyl esterase activity toward a broad range of substrates, and the corresponding kinetic constants for the methyl ferulate, ethyl ferulate, and methyl p-coumarate substrates were: K m values of 0.48, 6.3, and 1.9 mM, respectively, and k cat /K m values of 9.3, 3.8, and 3.8 mM?1 s?1, respectively.Conclusions
Feruloyl esterase from E. coli was expressed for the first time. BioH was confirmed to be a feruloyl esterase.12.
Background and aims
Layered profiles of designed soils may provide long-term benefits for green roofs, provided the vegetation can exploit resources in the different layers. We aimed to quantify Sedum root foraging for water and nutrients in designed soils of different texture and layering.Methods
In a controlled pot experiment we quantified the root foraging ability of the species Sedum album (L.) and S. rupestre (L.) in response to substrate structure (fine, coarse, layered or mixed), vertical fertiliser placement (top or bottom half of pot) and watering (5, 10 or 20 mm week?1).Results
Water availability was the main driver of plant growth, followed by substrate structure, while fertiliser placement only had marginal effects on plant growth. Root foraging ability was low to moderate, as also reflected in the low proportion of biomass allocated to roots (5–13%). Increased watering reduced the proportion of root length and root biomass in deeper layers.Conclusions
Both S. album and S. rupestre had a low ability to exploit water and nutrients by precise root foraging in substrates of different texture and layering. Allocation of biomass to roots was low and showed limited flexibility even under water-deficient conditions.13.
Satish K. Verma Kathryn Kingsley Marshall Bergen Camille English Matthew Elmore Ravindra N. Kharwar James F. White 《Plant and Soil》2018,422(1-2):223-238
Background and Aims
Leersia oryzoides, a wild relative of rice (Oryza sativa), may carry potential seed-borne bacterial endophytes which could be used to enhance growth of rice. We hypothesized that seed-associated bacteria from L. oryzoides would be compatible with rice and promote seedling growth, development, and survival.Methods
We isolated bacteria from seed of L. oryzoides and checked compatibility with rice as well as Bermuda grass seeds for seedling growth promotion. Internal colonisation of bacteria into root cells was observed by ROS staining and microscopic observation. Growth promoting bacteria were evaluated for IAA production, phosphate solubilization and antifungal activities.Results
Overall, ten bacteria were found to be growth promoting in rice seedlings with effects including restoration of root gravitropic response, increased root and shoot growth, and stimulation of root hair formation. All bacteria were identified by 16S rDNA sequencing. Six bacteria were found to become intracellular in root parenchyma and root hairs in rice and in Bermuda grass seedlings. Six bacteria were able to produce IAA in LB broth with highest (47.06 ± 1.99 μg ml?1) by LTE3 (Pantoea hericii). Nine isolates solubilized phosphate and inhibited at least one soil borne fungal pathogen.Conclusions
Seed bacteria of L. oryzoides are compatible with rice. Many of these bacteria become intracellular, induce root gravitropic response, increase root and shoot growth, and stimulate root hair formation in both rice and Bermuda grass seedlings. Presence of bacteria protects seedlings from soil pathogens during seedling establishment. This research suggests that bioprospecting microbes on near relatives of rice and other crop plants may be a viable strategy to obtain microbes to improve cultivation of crops.14.
Wenwen Zhang Zhaohui Chen Mengmeng Wu Zhong Shi Feng Zhu Guoqiang li Ting Ma 《Biotechnology letters》2016,38(6):991-997
Objective
To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs.Results
The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l?1 compared to 21 g ± 0.4 g l?1 in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties.Conclusions
Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.15.
Aims
Despite extensive studies on effects of elevated CO2 concentration ([CO2]e) on plant growth, few studies have investigated the responses of native grassland plant species to [CO2]e in terms of nutrient acquisition.Methods
The effects of [CO2]e (769 ± 23 ppm) on Artemisia frigida and Stipa krylovii, two dominant species in Inner Mongolia steppe were investigated by growing them for 7 weeks in Open-Top Chambers (OTC).Results
Exposure to [CO2]e enhanced shoot and root growth of A. frigida and S. krylovii. Elevated [CO2] increased photosynthetic rates (Pn) by 34 % in A. frigida but decreased Pn by 52 % in S. krylovii. Moreover, root-secreted acid phosphatase activity in A. frigida was stimulated by [CO2]e, while exudation of malate from roots of S. krylovii was suppressed by [CO2]e. Exposure to [CO2]e led to a decrease in P concentration in shoots and roots of A. frigida and S. krylovii, but total amount of P accumulated in shoots and roots of both species was increased by [CO2]e.Conclusions
The two dominant species in temperate steppes differed in their responses to [CO2]e, such that A. frigida was more adapted to [CO2]e than S. krylovii under low availability of soil P.16.
Huimei Huang Qinyun Ruan Meiyan Lin Lei Yan Chunyan Huang Liyun Fu 《Cardiovascular ultrasound》2017,15(1):14
Background
This study is aimed at investigating myocardial multi-directional systolic deformation in hypertensive with different left ventricular ejection fraction (LVEF), and exploring its contribution to LVEF.Methods
One hundred and twenty-three patients with primary hypertension (HT) were divided into group A (LVEF ≥ 55%), group B (45% ≤ LVEF < 50%, or 50% ≤ LVEF < 55% + LVEDVI ≥ 97 ml/m2), and group C (LVEF < 45%). Two-dimensional strain echocardiography (2DSE) including LV longitudinal strain (SL), radial strain (SR) and circumferential strain (SC) were measured.Results
SL decreased gradually from group A, B to C (all p < 0.05) while SR and SC were reduced only in group B and C (all p < 0.05). All strain measurements correlated to LVEF, with the strongest correlation in SC (r = ?0.82, p < 0.01) and the second in SL (r = ?0.76). The diastolic E/e increased from group A, B to C.Conclusions
Left ventricular multi-directional deformation correlated well to LVEF in hypertension and particularly SC, indicating that it was SC, not SL or SR, that makes the prominent contribution to left ventricular pump function.17.
Natalia Dłużniewska Piotr Podolec Maciej Skubera Monika Smaś-Suska Jacek Pająk Małgorzata Urbańczyk-Zawadzka Wojciech Płazak Maria Olszowska Lidia Tomkiewicz-Pająk 《Cardiovascular ultrasound》2018,16(1):28
Background
Tetralogy of Fallot (ToF) is the most common cyanotic congenital heart disease and the population of ToF repair survivors is growing rapidly. Adults with repaired ToF develop late complications. The aim of this study was to describe and analyze long-term follow-up of patients with repaired ToF.Methods
This is a retrospective cohort study. Consecutive 83 patients with repaired ToF who did not undergo pulmonary valve replacement were included. Mean age of all patients was 30.5?±?10.7. There were 49 (59%) male. Patients were divided into two groups according to the time since the repair (<?25 years and?≥?25 years). The electrocardiographic (ECG), cardiopulmonary exercise testing (CPET), echocardiographic and cardiac magnetic resonance (CMR) data were reviewed retrospectively.Results
In CPET values were not significantly different in the two groups. In CMR volumes of left and right ventricles were not significantly different in the two groups. There were no differences between the groups in ventricular ejection fraction, mass of ventricles, or pulmonary regurgitation fraction. Among all the patients, ejection fraction and left and right ventricle mass, indexed pulmonary regurgitation volume measured by CMR did not correlate with the time since repair. In ECG among all the patients, ejection fraction of the RV, measured in CMR, negatively correlated with QRS duration (r?=???0.43; p?<?0.001). There was a positive correlation between QRS duration and end diastolic volume of the RV (r?=?0.30; p?<?0.02), indexed end diastolic volume of the RV (r?=?0.29; p?=?0.04), RV mass (r?=?0.36; p?<?0.001) and left ventricle mass (r?=?0.26; p?=?0.04).Conclusion
Long-term survival and clinical condition after surgical correction of ToF in infancy is generally good and the late functional status in ToF – operated patients could be excellent up to 25 years after the repair. QRS duration could be an utility and easy factor to assessment of right ventricular function.Trial registration
The study protocol was approved by the local Ethics Committee. Each participant provided informed consent to participate in the study (license number 122.6120.88.2016 from 28.04.2016).18.
Xue-Ting Chen Jun-Bin Ji Yong-Chuang Liu Bin Ye Chao-Yang Zhou Xin Yan 《Biotechnology letters》2016,38(12):2109-2117
Objectives
To induce natural genetic competence in Bacillus amyloliquefaciens isolates through overexpression of the master regulator, ComK, from B. subtilis (ComK Bsu ).Results
Plasmid pUBXC carrying the xylose-inducible comK expression cassette was constructed using plasmid pUB110 as a backbone. Plasmid pUBXC could be transferred from B. subtilis to B. amyloliquefaciens through plasmid pLS20-mediated biparental conjugation. After being induced by xylose, four B. amyloliquefaciens strains harbouring plasmid pUBXC developed genetic competence. Under optimal conditions, the transformation efficiencies of plasmid DNA ranged from 129 ± 20.6 to 1.7 ± 0.1 × 105 cfu (colony-forming units) per μg DNA, and the transformation efficiencies of PCR-assembled deletion constructs ranged from 3.2 ± 0.76 to 3.5 ± 0.42 × 104 cfu per μg DNA in the four tested strains.Conclusion
Artificial induction of genetic competence through overexpressing ComK Bsu in B. amyloliquefaciens completed the tasks of replicative plasmid delivery and gene knockout via direct transformation of PCR-generated deletion cassettes.19.
Objectives
To engineer Escherichia coli for the heterologous production of di-rhamnolipids, which are important biosurfactants but mainly produced by opportunistic pathogen Pseudomonas aeruginosa.Results
The codon-optimized rhlAB and rhlC genes originating from P. aeruginosa and Burkholderia pseudomallei were combinatorially expressed in E. coli to produce di-rhamnolipids with varied congeners compositions. Genes involved in endogenous upstream pathways (rhamnose and fatty acids synthesis) were co-overexpressed with rhlAB–rhlC, resulting in variations of rhamnolipids production and congeners compositions. Under the shake-flask condition, co-overexpression of rfbD with rhlAB–rhlC increased rhamnolipids production (0.64 ± 0.02 g l?1) than that in strain only expressing rhlAB–rhlC (0.446 ± 0.009 g l?1), which was mainly composed of di-rhamnolipids congeners Rha–Rha–C10–C10.Conclusion
Biosynthesis of di-rhamnolipids and variations of congeners composition in genetically engineered E. coli strains were achieved via combiniations of mono-/di-rhamnolipids synthesis modules and endogenous upstream modules.20.
Willmar L. Leiser Marcus O. Olatoye H. Frederick W. Rattunde Günter Neumann Eva Weltzien Bettina I. G. Haussmann 《Plant and Soil》2016,409(1-2):51-64