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Publication
Journal: Journal of Biological Chemistry
June/3/1993
Abstract
The production of alpha-amidated peptides is accomplished through the sequential action of two enzymes, peptidylglycine alpha-hydroxylating monooxygenase (PHM) and peptidyl-alpha-hydroxyglycine alpha-amidating lyase (PAL), that are contained within the bifunctional peptidylglycine alpha-amidating monooxygenase (PAM) protein. Tissue-specific alternative splicing and endoproteolysis are known to generate both soluble and integral membrane mono- and bifunctional PAM proteins. In order to investigate the functional consequences of these differences we purified PAM-3, a soluble 95-kDa bifunctional form of the enzyme, from the spent medium of stably transfected hEK-293 cells. Using NH2-terminal sequence analysis of products of limited endoproteolysis and antibody cross-reactivity we identified protease-sensitive regions at the NH2 terminus, between the 35-kDa PHM and 42-kDa PAL domains and at the COOH terminus of the protein. Endoproteolytic removal of the COOH-terminal region from the bifunctional PAM-3 protein shifted the pH optimum of PHM to a more alkaline pH, increased the turnover number (kappa(cat)) of PHM and decreased its KM for alpha-N-acetyl-Tyr-Val-Gly; the catalytic properties of PAL were not altered. Since peptide amidation can be a rate-limiting step in the biosynthesis of neuropeptides, similar increases in PHM activity in vivo may play an important role in regulating the extent of peptide alpha-amidation.
Publication
Journal: Molecular Genetics and Metabolism
April/25/2010
Abstract
Phenylalanine ammonia lyase (PAL) has long been recognized as a potential enzyme replacement therapeutic for treatment of phenylketonuria. However, various strategies for the oral delivery of PAL have been complicated by the low intestinal pH, aggressive proteolytic digestion and circulation time in the GI tract. In this work, we report 3 strategies to address these challenges. First, we used site-directed mutagenesis of a chymotrypsin cleavage site to modestly improve protease resistance; second, we used silica sol-gel material as a matrix to demonstrate that a silica matrix can provide protection to entrapped PAL proteins against intestinal proteases, as well as a low pH of 3.5; finally, we demonstrated that PEGylation of AvPAL surface lysines can reduce the inactivation of the enzyme by trypsin.
Publication
Journal: Nutrition, Metabolism and Cardiovascular Diseases
July/19/2007
Abstract
BACKGROUND
Physical inactivity and raised blood lipids are two powerful risk factors for coronary heart disease (CHD). Incidence and mortality from CHD are expected to increase in developing countries. However, studies on the prevalence of cardiovascular risk factors in Africa are rare. In this study we examined the level of physical activity and serum lipids in rural and urban Tanzanians.
METHODS
Rural and urban inhabitants, n=985, mean age 43.8 years [SD, +/-8.9] were investigated. Physical activity level (PAL) was assessed by an interview-administered questionnaire and blood samples were collected and analysed for serum lipids.
RESULTS
The rural population (n=501) reported a substantially higher PAL than the urban population (n=484). They also had significantly lower mean weight, body mass index (BMI), T-cholesterol, LDL-cholesterol, and HDL-cholesterol, T-cholesterol/HDL-cholesterol ratio, triglycerides and Apolipoprotein A-1.
CONCLUSIONS
This study demonstrates that the urban Tanzanians have a considerably lower physical activity level and a more unfavourable lipid pattern than rural Tanzanians. These findings underline the importance of undertaking preventive measures to counter the increasing incidence of CHD in urban African populations.
Publication
Journal: Planta
January/15/2014
Abstract
Phenolic metabolism is influenced by the levels of sucrose, nitrogen and 2,4 dichlorophenoxyacetic acid (2,4-D) in the growth medium. Chromatographic evidence suggests that the principle products are polymers of leucocyanin, (-) epicatechin and (+) catechin, constituting condensed tannins. Comparison of ethanolic cell extracts with extracts from plant organs shows that although these compounds are present in parts of the plant they are not the major phenolics.Cells maintained in a modified Heller's medium containing 9.0×10(-7) M 2,4-D produce increased levels of tannins from mid passage (day 12) onwards. The presence of 2,4-D at 9.0×10(-6) M supresses this response and increased initial sucrose levels cause the amount of tannins to be greater. At the period when tannin levels increase the standard medium is exhaused of its nitrogen sources, urea and nitrate. Increased initial nitrogen levels delay the beginning of increased tannin production and the addition of urea or 2,4-D to cultures already containing high levels of tannins causes the tannin content per gram fresh weight and per culture to decline. These results indicate an antagonism between tannin synthesis and nitrogen metabolism. The activity of phenylalanine ammonia-lyase EC 4.1.1.5. (PAL) estimated by a spectrophotometric method in acetone powders derived from Acer cells increases three to four fold at the onset of increased tannin synthesis and then declines sharply. The phase of high PAL activity correlates with the exhausion of the medium nitrogen sources.
Publication
Journal: International Journal of Peptide and Protein Research
November/26/1995
Abstract
Indolicidin, a novel tryptophan-rich microbicidal tridecapeptide amide isolated originally from granules of bovine neutrophils, has been prepared by optimized manual and automated protocols of stepwise solid-phase synthesis with N alpha-9-fluorenylmethyloxycarbonyl (Fmoc) amino acid derivatives. Both standard polystyrene (PS) and polyethylene glycol-polystyrene (PEG-PS) graft supports were used in combination with handles that provide C-terminal peptide amides: 5-(4-Fmoc-aminomethyl-3,5-dimethoxyphenoxy)valeric acid (PAL) or 5-(9-Fmoc-aminoxanthen-2-oxy)valeric acid (XAL). Final deprotection/cleavage was carried out with reagent K, trifluoroacetic acid-phenol-water-thioanisole-1,2-ethanedithiol (82.5:5:5:5:2.5), or reagent B, trifluoroacetic acid-phenol-water-tri(isopropyl)silane (88:5:5:2), and related cocktails. Initial purities as high as 93% were obtained immediately following cleavage. In the largest-scale synthesis carried out, 0.8 g of HPLC-purified indolicidin >> 99% pure) was obtained, representing a 39% overall yield based on C-terminal Arg(Pmc) anchored to PAL-PS-resin. The main synthetic product, and some by-products, were characterized by analytical high-performance liquid chromatography (HPLC), sequencing, and fast atom bombardment mass spectrometry (FABMS). The antimicrobial potencies of natural and synthetic indolicidin, as determined by in vitro antibacterial and antifungal assays, were identical. Further, the reactivities of natural and synthetic peptides with anti-indolicidin antibody were indistinguishable.
Publication
Journal: Journal of Medicinal Chemistry
July/11/2002
Abstract
The melanocortin pathway is an important participant in obesity and energy homeostasis. The centrally located melanocortin-3 and melanocortin-4 receptors (MC3R, MC4R) are involved in the metabolic and food intake aspects of energy homeostasis and are stimulated by melanocortin agonists such as alpha-melanocyte stimulation hormone (alpha-MSH). The melanocortin agonists contain the putative message sequence "His-Phe-Arg-Trp", and it has been well documented that inversion of chirality of the Phe to DPhe results in a dramatic increase in melanocortin receptor potency. Herein, we report a tetrapeptide library based on the template Ac-His-DPhe-Arg-Trp-NH(2), consisting of 17 members that have been modified at the His(6) position (alpha-MSH numbering) and pharmacologically characterized for agonist activity at the mouse melanocortin receptors MC1R, MC3R, MC4R, and MC5R. These studies provide further experimental evidence that the His(6) position can determine MC4R versus MC3R agonist selectivity and that chemically nonreactive side chains may be substituted for the imidazole ring (generally needs to be side chain protected in synthetic schemes) in the design of MC4R-selective, small-molecule, non-peptide agonists. Specifically, the tetrapeptide containing the amino-2-naphthylcarboxylic acid (Anc) amino acid at the His position resulted in a potent agonist at the mMC4R (EC(50) = 21 nM), was a weak mMC3R micromolar antagonist (pA(2) = 5.6, K(i) = 2.5 microM), and possessed >4700-fold agonist selectivity for the MC4R versus the MC3R. Substitution of the His(6) amino acid in the tetrapeptide template by the Phe, Anc, 3-(2-thienyl)alanine (2Thi), and 3-(4-pyridinyl)alanine (4-Pal) resulted in equipotency or only up to a 7-fold decrease in potency, compared to the His(6)-containing tetrapeptide at the mMC4R, demonstrating that these amino acid side chains may be substituted for the imidazole in the design of MC4R-selective non-peptide molecules.
Publication
Journal: Zeitschrift fur Naturforschung. Section C, Biosciences
July/21/1980
Abstract
L-alpha-Aminooxy-beta-phenylpropionic acid (AOPP), a potent competitive inhibitor of phenylalanine ammonia-lyase (PAL), blocked light-induced phenylpropanoid synthesis in excised buckwheat hypocotyls and produced an up to 40-fold increase in the endogenous phenylalanine concentration, while the level of all other amino acids was hardly affected. After a 24 h incubation in the light in the presence of 0.3 or 1 mM AOPP phenylalanine alone constituted about 25% of the total soluble amino acids, compared to appr. 1% in the controls. In the presence of AOPP illuminated hypocotyls accumulated nearly 3 times more phenylalanine than hypocotyls kept in the dark, indicating an enhancing effect of light on the flow of carbon through the shikimate pathway. Exogenously added [14C]phenylalanine was extensively metabolized by control tissue, but accumulated in AOPP treated tissue. In the presence of AOPP radioactivity from [14C]shikimate accumulated predominantly in phenylalanine, and the flow of shikimate into tyrosine and phenylalanine was not affected by the inhibitor. Therefore, under these conditions no feedback control of phenylalanine and tyrosine synthesis from shikimate is apparent in buckwheat hypocotyls.
Publication
Journal: Pharmacology Biochemistry and Behavior
January/25/2015
Abstract
The use of touch-screen equipped operant boxes is an increasingly popular approach for modeling human cognition in the rodent. However little data is currently available describing the effects of pharmacological manipulations on touch-screen based tasks. Owing to the relationship between performance on visual-spatial paired associates learning (PAL) with schizophrenia and Alzheimer's disease one task of specific interest is the touch-screen PAL task developed for rodents (J. Talpos et al., 2009). The goal of this study was to profile a range of the commonly used pharmacological models of schizophrenia and Alzheimer's disease to investigate the sensitivity of PAL to these models of disease. Male Lister hooded rats were trained on PAL until stable performance was obtained. The effects of PCP, ketamine, amphetamine, LSD, scopolamine, and biperiden (recently proposed as an alternative to scopolamine) were then tested on animals performing the PAL task. While all compounds influenced responding during PAL, only PCP and amphetamine impaired performance with minimal changes in secondary measures (response latencies, trials completed). Surprisingly ketamine did not cause a change in percent correct despite being an NMDA antagonist, indicating that not all NMDA antagonists are equal in the touch-screen platform. This finding is in agreement with existing literature showing differential effects of NMDA antagonists on a wide variety of behavioral assays include tasks of attention, memory, and cognitive flexibility (Gilmour et al., 2009; Dix et al., 2010; Smith et al., 2011). Moreover biperiden showed no benefit when compared to scopolamine, highlighting the current lack of an effective pharmacological model of cholinergic dysfunction in the touch-screen platform. These data demonstrate that performance on PAL can be disrupted by common pharmacological disease models, suggesting that PAL may have the sensitivity to serve as a translational test for the study of cognition in humans.
Publication
Journal: Nature Communications
November/15/2015
Abstract
Understanding the mechanisms by which climate variability affects multiple trophic levels in food webs is essential for determining ecosystem responses to climate change. Here we use over two decades of data collected by the Palmer Long Term Ecological Research program (PAL-LTER) to determine how large-scale climate and local physical forcing affect phytoplankton, zooplankton and an apex predator along the West Antarctic Peninsula (WAP). We show that positive anomalies in chlorophyll-a (chl-a) at Palmer Station, occurring every 4-6 years, are constrained by physical processes in the preceding winter/spring and a negative phase of the Southern Annular Mode (SAM). Favorable conditions for phytoplankton included increased winter ice extent and duration, reduced spring/summer winds, and increased water column stability via enhanced salinity-driven density gradients. Years of positive chl-a anomalies are associated with the initiation of a robust krill cohort the following summer, which is evident in Adélie penguin diets, thus demonstrating tight trophic coupling. Projected climate change in this region may have a significant, negative impact on phytoplankton biomass, krill recruitment and upper trophic level predators in this coastal Antarctic ecosystem.
Publication
Journal: Cancer Research
October/2/2011
Abstract
Many human cancer cells are sensitive to killing by the proapoptotic ligand TNF-related apoptosis-inducing ligand (TRAIL), which is under study for cancer treatment in clinical trials. The TRAIL receptor (TRAIL-R1; also known as death receptor 4) is a transmembrane receptor that mediates TRAIL-induced apoptosis in cancer cells. In this study, we show that retinoids sensitize cancer cells to TRAIL-induced apoptosis by upregulating expression of TRAIL-R1. All-trans retinoic acid (ATRA) upregulated TRAIL-R1 expression in human cancer cells at the transcriptional level. The ability of ATRA to activate TRAIL-R1 expression was inhibited by retinoic acid receptor (RAR) antagonists or siRNAs, but augmented by several RAR agonists. In analyzing how ATRA induces RAR-dependent transcriptional upregulation of TRAIL-R1, we identified 2 putative retinoic acid response elements termed Pal-17 (a palindrome separated by 17 bases) and DR-11 (a direct repeat separated by 11 bases) in the 5'-flanking region of TRAIL-R1 gene. Deletion of DR-11, but not Pal-17, abrogated the ability of ATRA to stimulate TRAIL-R1 promoter activity. Consistent with this observation, RAR binding to DR-11, but not to Pal-17, was detected by chromatin immunoprecipitation assay in ATRA-treated cells, arguing that DR-11 was responsible for ATRA-mediated activation of the TRAIL-R1 gene. ATRA augmented TRAIL-induced apoptosis of cancer cells, and this activity was attenuated by a blockade to upregulation of TRAIL-R1 expression. Taken together, our findings establish that ATRA accentuates TRAIL-induced apoptosis, reveal a novel mechanism by which retinoids modulate apoptosis, and suggest a novel strategy to augment the anti-cancer activity of TRAIL.
Publication
Journal: Microvascular Research
October/27/1993
Abstract
The pulmonary vasculature is of great physiological/pathological significance. We have isolated and cultured microvessel endothelial cells (HuLEC) from lung tissue obtained from lung transplant recipients by modification of published methods. Pure cultures of HuLEC were isolated by mechanical disaggregation of the tissue prior to sequential dispase and trypsin digestion to obtain microvessel fragments. Magnetic beads (Dynabeads) coated with Ulex europaeus agglutinin-1 were then used to enhance the purity of cultures at the first passage. HuLEC formed contact-inhibited "cobblestone" monolayers on gelatin and fibronectin substrates and capillary-like "tubes" on Matrigel and accumulated acetylated low-density lipoprotein. Immunofluorescent characterization of these cells revealed the presence of von Willebrand Factor, angiotensin-converting enzyme, and thrombomodulin and the expression of antigens for the endothelial cell-specific monoclonal antibodies EN4, PAL-E, and H4-7/33. The endothelial origin of these cells was confirmed by the demonstration of the cell adhesion molecules, platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31), and E-selectin (endothelial leukocyte adhesion molecule-1/ELAM-1) upon stimulation with TNF alpha. These cells should provide a useful tool for studying various aspects of pathology and biology of the pulmonary microvasculature in vitro.
Publication
Journal: Analytical Chemistry
August/7/2012
Abstract
A novel method using resistive pulse sensors for electrokinetic surface charge measurements of nanoparticles is presented. This method involves recording the particle blockade rate while the pressure applied across a pore sensor is varied. This applied pressure acts in a direction which opposes transport due to the combination of electro-osmosis, electrophoresis, and inherent pressure. The blockade rate reaches a minimum when the velocity of nanoparticles in the vicinity of the pore approaches zero, and the forces on typical nanoparticles are in equilibrium. The pressure applied at this minimum rate can be used to calculate the zeta potential of the nanoparticles. The efficacy of this variable pressure method was demonstrated for a range of carboxylated 200 nm polystyrene nanoparticles with different surface charge densities. Results were of the same order as phase analysis light scattering (PALS) measurements. Unlike PALS results, the sequence of increasing zeta potential for different particle types agreed with conductometric titration.
Publication
Journal: Plant Physiology
February/18/2017
Abstract
Seedlings of 17 rice (Oryza sativa L.) cultivars were classified on the basis of anthocyanin pigmentation into three groups: an acyanic group with 9 cultivars, a moderately cyanic group with 5 cultivars, and a cyanic group with 3 cultivars. Seedlings of the cyanic group were deep purple in color, possessing copious amounts of anthocyanin in shoots. Sunlight (SL)-mediated anthocyanin and phenylalanine ammonia lyase (PAL) induction in a cyanic cultivar, purple puttu, was compared with an acyanic cultivar, black puttu. A brief exposure of dark-grown purple puttu seedlings to SL induced anthocyanin formation during a subsequent dark period with a peak at 24 h. The magnitude of SL-mediated anthocyanin induction is age dependent, the 4-d-old seedlings being the most responsive to SL. The anthocyanin induction in purple puttu seedlings is mediated exclusively by the ultraviolet-B (UV-B) component of SL. The SL-triggered anthocyanin induction was reduced by about 30% by a terminal far-red light pulse and was restored by a red light pulse, indicating the role of phytochrome in modulation of anthocyanin level. The SL-mediated induction of PAL showed two peaks, one at 4 h and the other at 12 h. Whereas the first PAL peak (4 h) was induced by phytochrome and was seen in both cultivars, the second PAL peak (12 h) was inducible by UV-B only in the cyanic purple puttu cultivar.
Publication
Journal: Cancer Science
September/20/2007
Abstract
Transfer of genetic information during mitosis is accurately conducted by proper condensation and segregation of chromosomes, for which condensins play a central role. Both condensin I and II have common structural maintenance of chromosomes subunits, named hCAP-C and hCAP-E. Pyothorax-associated lymphoma (PAL) is a non-Hodgkin's lymphoma developing in the pleural cavity of patients with long-standing pyothorax. Mutations of hCAP-C and hCAP-E were investigated in 24 leukemia-lymphoma cell lines including eight PAL cell lines, and their influences in chromosome morphology were evaluated. Heterozygous point mutations within hCAP-C were found in two PAL cell lines and corresponding tumor samples (OPL-3 and OPL-7). Deletion of exon 24 within hCAP-E and a point mutation at the donor splice site of intron 24 were detected in OPL-5 and original tumor samples. OPL-5 showed an extensive reduction in expression of not only hCAP-E but also hCAP-C proteins. OPL-5 occasionally showed the chromosome bridge in anaphase and telophase, indicating that segregation is not accurate. OPL-7 showed reduced hCAP-C protein expression, abnormality in chromosome length and width, and abnormal aggregates of hCAP-C protein. These findings indicated that condensin gene alteration might play a role in genome instability, which accelerates the accumulation of other gene alterations in PAL.
Publication
Journal: Retrovirology
March/17/2008
Abstract
BACKGROUND
Retroviruses selectively encapsidate two copies of their genomic RNA, the Gag protein binding a specific RNA motif in the 5' UTR of the genome. In human immunodeficiency virus type 2 (HIV-2), the principal packaging signal (Psi) is upstream of the major splice donor and hence is present on all the viral RNA species. Cotranslational capture of the full length genome ensures specificity. HIV-2 RNA dimerisation is thought to occur at the dimer initiation site (DIS) located in stem-loop 1 (SL-1), downstream of the main packaging determinant. However, the HIV-2 packaging signal also contains a palindromic sequence (pal) involved in dimerisation. In this study, we analysed the role of the HIV-2 packaging signal in genomic RNA dimerisation in vivo and its implication in viral replication.
RESULTS
Using a series of deletion and substitution mutants in SL-1 and the Psi region, we show that in fully infectious HIV-2, genomic RNA dimerisation is mediated by the palindrome pal. Mutation of the DIS had no effect on dimerisation or viral infectivity, while mutations in the packaging signal severely reduce both processes as well as RNA encapsidation. Electron micrographs of the Psi-deleted virions revealed a significant reduction in the proportion of mature particles and an increase in that of particles containing multiple cores.
CONCLUSIONS
In addition to its role in RNA encapsidation, the HIV-2 packaging signal contains a palindromic sequence that is critical for genomic RNA dimerisation. Encapsidation of a dimeric genome seems required for the production of infectious mature particles, and provides a promising therapeutic target.
Publication
Journal: Controlled clinical trials
October/17/2001
Abstract
The Correction of Myopia Evaluation Trial (COMET) is a multicenter, randomized, double-masked, controlled clinical trial evaluating whether there is a difference in the progression of myopia between children wearing progressive addition lenses (PALs) versus conventional single vision lenses (SVLs), as measured by cycloplegic autorefraction. Axial length, measured by A-scan ultrasonography, is an additional outcome measure. To meet the recruitment goal of 450 participants, eligible children ages 6-11 years (inclusive) with myopia in both eyes (spherical equivalent between -1.25 diopters (D) and -4.50 D, astigmatism < or = 1.50 D, and anisometropia < 1.00 D) were recruited at four clinical centers between September 1997 and September 1998. Children who participated were assigned to receive PALs (Varilux Comfort with a +2.00 D addition) or SVLs. Measures include standardized cycloplegic autorefraction (Nidek ARK700A autorefractor), axial length (Sonomed A2500 ultrasound), subjective refraction (Marco TRS system), visual acuity (modified Early Treatment Diabetic Retinopathy Study protocol), accommodation (Canon R-1), and phoria (cover test and Maddox rod). Outcome measures are collected annually; adherence is assessed and prescriptions updated semiannually. Participants are being followed for at least 3 years. COMET enrolled 469 children. Their mean age is 9.3 years (range 6-11 years); 52% are female. COMET children are ethnically diverse, according to a self-report with 46% White, 26% African American, 14% Hispanic, and 8% Asian. Best-corrected visual acuity is better than 20/32 in both eyes. Baseline mean (+/-SD) cycloplegic refractive correction is -2.38 D (+/-0.81) in the right eye and -2.40 D (+/-0.82) in the left eye; mean (+/-SD) axial length is 24.1 mm (+/-0.7) in both eyes. Follow-up of these children will provide a first step in answering the important question of whether there are effective means to slow myopia progression. Study results should be applicable to a large proportion of children with myopia. The study will also provide useful information on myopia progression in children wearing conventional single vision lenses.
Publication
Journal: Annals of the Rheumatic Diseases
September/21/2003
Abstract
OBJECTIVE
To obtain insight into the interaction between daily physical activity and components of health related physical fitness in children with juvenile idiopathic arthritis.
METHODS
Forty five patients (10 male/35 female; mean (SD) age 8.9 (2.2) years) participated in the study. Body mass, height, skinfold thickness, number of swollen joints, and joint range of motion were determined. The maximal oxygen consumption (VO(2peak)) was assessed during a graded maximal bicycle exercise test. Daily physical activity levels were measured with a Caltrac activity monitor and a parental physical activity rating (PAL) on a five point Likert scale.
RESULTS
Partial correlation coefficients (to control for age) between physical activity and indices of health related physical fitness showed significant relationships between Caltrac motion counts and absolute VO(2peak) (r=0.31) and relative VO(2peak) (r=0.34), but not with the indices of body composition. There was also a significant correlation between PAL and relative VO(2peak) (r=0.33).
CONCLUSIONS
Physical activity was significantly related to cardiorespiratory fitness but not to body composition in children with juvenile idiopathic arthritis. A longitudinal follow up should show whether an active lifestyle protects for loss of aerobic fitness in this patient group.
Publication
Journal: Journal of Chemical Ecology
November/25/2013
Abstract
The effect of both caterpillar herbivory and artificial damage on phenylalanine ammonia lysase (PAL) activity of birch foliage was measured, using an intact cell assay. After artificial damage there was a small increase in PAL activity in damaged leaves but no change in adjacent undamaged ones. Insect grazing produced a larger increase in PAL activity, and the enzyme activity was also increased in adjacent undamaged leaves. Artificial damage increased the phenolic levels of the damaged leaves. Insect grazing caused a larger, longer-lasting increase in phenolic levels and also elevated phenolic levels in undamaged leaves. The possible role of these wound-induced biochemical changes in birch is discussed.
Publication
Journal: Metabolism: Clinical and Experimental
February/8/1998
Abstract
The bicarbonate-urea method for measuring CO2 production was applied to eight free-living patients (mean age, 68 +/- 10 years; mean weight, 69 +/- 10 kg; mean height, 1.65 +/- 0.10 m) with unresectable small-cell lung cancer for a period of 1 day (n = 5) or 2 days (n = 3). The basal metabolic rate (BMR) was measured in all subjects. The technique was first validated against whole-body indirect calorimetry over an additional 24-hour period in five of these subjects. The bicarbonate-urea method predicted net CO2 production to be 102.1% +/- 3.4% of that measured by whole-body indirect calorimetry, and energy expenditure, 101.5% +/- 3.8% of the measured calorimeter value (8.1 +/- 1.6 MJ/d). The 24-hour recovery of label in CO2 excreted by the body was 95.6% +/- 0.5%. In free-living conditions, the bicarbonate-urea method predicted energy expenditure to be 9.0 +/- 2.6 MJ/d. BMR was elevated by a mean of 6% (P < .05) compared with the Schofield standards. The physical activity level ([PAL] the ratio of total energy expenditure [TEE] to BMR) was variable (1.15 to 1.87), but the mean value was only 1.36 +/- 0.22, considerably less than that of moderately active healthy subjects with estimated PAL values of 1.55 (P < .05) to 1.65 (P < .01) and the mean results obtained by doubly labeled water (previous studies) in healthy age- and sex-matched subjects. This is the first time a tracer method for measuring CO2 production and energy expenditure has been validated against whole-body 24-hour indirect calorimetry in patients with lung cancer or a systemic inflammatory reaction. The agreement between the two methods is similar to that observed in normal subjects. This is also the first time a tracer method has been used to measure energy expenditure in free-living patients with lung cancer. The results suggest that TEE and the energy requirements necessary to maintain energy balance were not increased despite basal hypermetabolism, because of the associated decrease in physical activity.
Publication
Journal: Plant Physiology
November/23/2000
Abstract
Cytochrome P450 monooxygenases (P450s) mediate a wide range of oxidative reactions involved in the biosynthesis of phenylpropanoids, terpenes, and alkaloids. Two pea (Pisum sativum) P450 cDNAs (CYP73A9v1, encoding trans-cinnamic acid hydroxylase [t-CAH] in the core phenylpropanoid pathway, and CYP82A1v1, possibly encoding an activity in a late branch of the phenylpropanoid pathway) have previously been described. Of three CYP73A9 genes now isolated, the CYP73A9v1 gene is full-length with two introns at positions conserved in other t-CAH genes, and the CYP73A9v2 and CYP73A9v3 gene fragments are 5'-truncated and lack introns. The full-length CYP82A1v2 gene contains a single intron at an alternate position. Nucleotide searches of the CYP73A9v1 and CYP82A1v2 promoters have indicated that the regulatory sequences for these early and late phenylpropanoid transcripts are substantially different. The P-, L-, and H-boxes identified in white light-, ultraviolet light-, and elicitor-induced footprints in early phenylpropanoid promoters (phenylalanine ammonia lyase [PAL], 4-coumarate coenzyme A:ligase [4-CL], and chalcone synthase [CHS]) are conserved in the t-CAH promoter and are absent from the CYP82A1v2 promoter. Both promoters contain TCA motifs identified in stress-responsive promoters, box IV elements identified in elicitor-responsive PAL and CHS promoters, and spatially conserved wound-response elements potentially coordinating regulation of these wound-responsive promoters.
Publication
Journal: Acta Biochimica Polonica
October/13/2011
Abstract
Species-specific changes in expression of phenylalanine ammonia-lyase (PAL) and lignin content were detected in roots of soybean (Glycine max L.) and lupine (Lupinus luteus L.) seedlings treated with different concentrations of cadmium (Cd(2+), 0-25 mg/l) or lead (Pb(2+), 0-350 mg/l). The stimulatory effect of both metals was observed in mRNA coding for PAL in soybean. In the case of lupine, changes of PAL mRNA level were dependent on the metal used: Cd(2+) caused a decrease, whereas Pb(2+) an increase of PAL transcript level. The activity of PAL was enhanced in both plant species at higher metal concentrations (15-25 mg/l of Cd(2+) or 150-350 mg/l of Pb(2+)); however it was not directly correlated with PAL mRNA. This suggests a transcriptional and posttranscriptional control of PAL expression under heavy metals stress. In soybean, Cd(2+) or Pb(2+) treatment increased lignin content, while in lupine the effect was opposite. The decreased lignin accumulation in lupine roots in response to heavy metals, despite an increased PAL activity, suggests that the activated phenylpropanoid pathway was involved in the synthesis of secondary metabolites other than lignin.
Publication
Journal: Planta
December/1/2010
Abstract
Lemon balm (Melissa officinalis, Lamiaceae) is a well-known medicinal plant. Amongst the biologically active ingredients are a number of phenolic compounds, the most prominent of which is rosmarinic acid. To obtain better knowledge of the biosynthesis of these phenolic compounds, two enzymes of the general phenylpropanoid pathway, phenylalanine ammonia-lyase (<em>PAL</em>) and 4-coumarate:coenzyme A-ligase (4CL), were investigated in suspension cultures of lemon balm. Mo<em>PAL</em>1 and Mo4CL1 cDNAs were cloned and heterologously expressed in Escherichia coli and the enzymes characterised. Expression analysis of both genes showed a correlation with the enzyme activities and rosmarinic acid content during a cultivation period of the suspension culture. Southern-blot analysis suggested the presence of most probably two gene copies in the M. officinalis genome of both <em>PAL</em> and 4CL. The genomic DNA sequences of Mo<em>PAL</em>1 and Mo4CL1 were amplified and sequenced. Mo<em>PAL</em>1 contains one phase 2 intron of 836 bp at a conserved site, whilst Mo4CL1 was devoid of introns.
Publication
Journal: Trials
March/19/2020
Abstract
Myopia is increasing in prevalence and is currently recognized as a significant public health issue worldwide, particularly in China. Once myopia develops, appropriate clinical interventions need to be prescribed to slow its progression. Currently, several publications indicate that myopic defocus (MD) retards eye growth and myopia progression. However, no clinical trials have compared the outcomes of different MD spectacle lenses in the same observational group, especially in mainland China. The aim of the present study is to compare the myopia control efficiency of two different MD spectacle lenses: defocus incorporated multiple segments (DIMS) lenses and Apollo progressive addition lenses (PALs).The trial is designed as a 3-year, prospective, randomized, multicenter clinical trial of schoolchildren treated with DIMS lenses and PALs. A total of 600 Chinese primary school children aged 6-12 years will be recruited, and each group is intended to include 300 subjects. The inclusion criteria are myopia between - 1.00 and - 5.00 diopters and astigmatism ≤ 1.50 diopters. The follow-up time points will be 1 month (m), 3 m, 6 m, 12 m, 18 m, 24 m, 30 m, and 36 m. The primary outcome will be determined by the difference between the two groups in cycloplegic spherical equivalent refraction between baseline and the last follow-up visit. The secondary outcome is the axial length, and the exploratory outcomes include ocular biometric measures, peripheral refraction, binocular vision, accommodation, compliance, and the results of questionnaires related to wearing experiences.The present study will be the first randomized controlled trial in myopic primary school children treated with DIMS lenses and PALs in China. The results will indicate whether and how much different MD mechanisms retard myopia progression and axial elongation. In addition, the comparison will provide information on the clinical efficacy and safety of DIMS lenses and PALs, including information related to wearing experiences and visual function.Chinese Clinical Trial Registry (ChiCTR), ChiCTR1900025645. Registered on 3 September 2019. http://www.chictr.org.cn/showproj.aspx?proj=42927.
Publication
Journal: BMJ Open Sport and Exercise Medicine
November/13/2018
Abstract
UNASSIGNED
To examine the impact of acute classroom movement break (CMB) and physically active learning (PAL) interventions on physical activity (PA), cognition, academic performance and classroom behaviour.
UNASSIGNED
Systematic review.
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PubMed, EBSCO, Academic Search Complete, Education Resources Information Center, PsycINFO, SPORTDiscus, SCOPUS and Web of Science.
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Studies investigating school-based acute bouts of CMB or PAL on (PA), cognition, academic performance and classroom behaviour. The Downs and Black checklist assessed risk of bias.
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Ten PAL and eight CMB studies were identified from 2929 potentially relevant articles. Risk of bias scores ranged from 33% to 64.3%. Variation in study designs drove specific, but differing, outcomes. Three studies assessed PA using objective measures. Interventions replaced sedentary time with either light PA or moderate-to-vigorous PA dependent on design characteristics (mode, duration and intensity). Only one study factored individual PA outcomes into analyses. Classroom behaviour improved after longer moderate-to-vigorous (>10 min), or shorter more intense (5 min), CMB/PAL bouts (9 out of 11 interventions). There was no support for enhanced cognition or academic performance due to limited repeated studies.
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Low-to-medium quality designs predominate in investigations of the acute impacts of CMB and PAL on PA, cognition, academic performance and classroom behaviour. Variable quality in experimental designs, outcome measures and intervention characteristics impact outcomes making conclusions problematic. CMB and PAL increased PA and enhanced time on task. To improve confidence in study outcomes, future investigations should combine examples of good practice observed in current studies.
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CRD42017070981.
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