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2.
J Steroid Biochem Mol Biol ; 175: 138-145, 2018 01.
Article in English | MEDLINE | ID: mdl-28161533

ABSTRACT

Vitamin D deficiency is common in patients with chronic obstructive pulmonary disease (COPD), yet a comprehensive analysis of environmental and genetic determinants of serum 25-hydroxyvitamin D (25[OH]D) concentration in patients with this condition is lacking. We conducted a multi-centre cross-sectional study in 278 COPD patients aged 41-92 years in London, UK. Details of potential environmental determinants of vitamin D status and COPD symptom control and severity were collected by questionnaire, and blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction. All participants performed spirometry and underwent measurement of weight and height. Quadriceps muscle strength (QS) was measured in 134 participants, and sputum induction with enumeration of lower airway eosinophil and neutrophil counts was performed for 44 participants. Thirty-seven single nucleotide polymorphisms (SNP) in 11 genes in the vitamin D pathway (DBP, DHCR7, CYP2R1, CYP27B1, CYP24A1, CYP27A1, CYP3A4, LRP2, CUBN, RXRA, and VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration and to determine whether vitamin D status or genetic factors independently associated with % predicted forced expiratory volume in one second (FEV1), % predicted forced vital capacity (FVC), the ratio of FEV1 to FVC (FEV1:FVC), daily inhaled corticosteroid (ICS) dose, respiratory quality of life (QoL), QS, and the percentage of eosinophils and neutrophils in induced sputum. Mean serum 25(OH)D concentration was 45.4nmol/L (SD 25.3); 171/278 (61.5%) participants were vitamin D deficient (serum 25[OH]D concentration <50nmol/L). Lower vitamin D status was independently associated with higher body mass index (P=0.001), lower socio-economic position (P=0.037), lack of vitamin D supplement consumption (P<0.001), sampling in Winter or Spring (P for trend=0.006) and lack of a recent sunny holiday (P=0.002). Vitamin D deficiency associated with reduced % predicted FEV1 (P for trend=0.060) and % predicted FVC (P for trend=0.003), but it did not associate with FEV1:FVC, ICS dose, QoL, QS, or the percentage of eosinophils or neutrophils in induced sputum. After correction for multiple comparisons testing, genetic variation in the vitamin D pathway was not found to associate with serum 25(OH)D concentration or clinical correlates of COPD severity. Vitamin D deficiency was common in this group of COPD patients in the UK, and it associated independently with reduced % predicted FEV1 and FVC. However, genetic variation in the vitamin D pathway was not associated with vitamin D status or severity of COPD.


Subject(s)
Pulmonary Disease, Chronic Obstructive/epidemiology , Vitamin D Deficiency/epidemiology , Vitamin D/analogs & derivatives , Adult , Aged , Aged, 80 and over , Body Mass Index , Cross-Sectional Studies , Cytochrome P-450 Enzyme System/blood , Cytochrome P-450 Enzyme System/genetics , DNA-Binding Proteins/blood , DNA-Binding Proteins/genetics , Eosinophils/metabolism , Eosinophils/pathology , Female , Gene Expression Regulation , Humans , London/epidemiology , Low Density Lipoprotein Receptor-Related Protein-2/blood , Low Density Lipoprotein Receptor-Related Protein-2/genetics , Male , Middle Aged , Neutrophils/metabolism , Neutrophils/pathology , Oxidoreductases Acting on CH-CH Group Donors/blood , Oxidoreductases Acting on CH-CH Group Donors/genetics , Prevalence , Pulmonary Disease, Chronic Obstructive/blood , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/genetics , Racial Groups , Receptors, Calcitriol/blood , Receptors, Calcitriol/genetics , Receptors, Cell Surface/blood , Receptors, Cell Surface/genetics , Respiratory Function Tests , Severity of Illness Index , Transcription Factors/blood , Transcription Factors/genetics , Vitamin D/blood , Vitamin D Deficiency/blood , Vitamin D Deficiency/complications , Vitamin D Deficiency/genetics
3.
J Steroid Biochem Mol Biol ; 175: 88-96, 2018 01.
Article in English | MEDLINE | ID: mdl-27825992

ABSTRACT

Vitamin D deficiency is common in children with asthma, and it associates with poor asthma control, reduced forced expiratory volume in one second (FEV1) and increased requirement for inhaled corticosteroids (ICS). Cross-sectional studies investigating the prevalence, determinants and clinical correlates of vitamin D deficiency in adults with asthma are lacking. We conducted a multi-centre cross-sectional study in 297 adults with a medical record diagnosis of ICS-treated asthma living in London, UK. Details of potential environmental determinants of vitamin D status, asthma control and medication use were collected by questionnaire; blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction, and participants underwent measurement of weight, height and fractional exhaled nitric oxide concentration (FeNO), spirometry and sputum induction for determination of lower airway eosinophil counts (n=35 sub-group). Thirty-five single nucleotide polymorphisms (SNP) in 11 vitamin D pathway genes (DBP, DHCR7, RXRA, CYP2R1, CYP27B1, CYP24A1, CYP3A4 CYP27A1, LRP2, CUBN, VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration, and to determine whether vitamin D status was independently associated with Asthma Control Test (ACT) score, ICS dose, FeNO, forced vital capacity (FVC), FEV1 or lower airway eosinophilia. Mean serum 25(OH)D concentration was 50.6nmol/L (SD 24.9); 162/297 (54.5%) participants were vitamin D deficient (serum 25(OH)D concentration <50nmol/L). Lower vitamin D status was associated with higher body mass index (P=0.014), non-White ethnicity (P=0.036), unemployment (P for trend=0.012), lack of vitamin D supplement use (P<0.001), sampling in Winter or Spring (P for trend <0.001) and lack of a recent sunny holiday abroad (P=0.030), but not with potential genetic determinants. Vitamin D status was not found to associate with any marker of asthma control investigated. Vitamin D deficiency is common among UK adults with ICS-treated asthma, and classical environmental determinants of serum 25(OH)D operate in this population. However, in contrast to studies conducted in children, we found no association between vitamin D status and markers of asthma severity or control.


Subject(s)
Asthma/epidemiology , Vitamin D Deficiency/epidemiology , Vitamin D/analogs & derivatives , Administration, Inhalation , Adolescent , Adrenal Cortex Hormones/therapeutic use , Adult , Aged , Anti-Asthmatic Agents/therapeutic use , Asthma/blood , Asthma/complications , Asthma/drug therapy , Body Mass Index , Cross-Sectional Studies , Cytochrome P-450 Enzyme System/blood , Cytochrome P-450 Enzyme System/genetics , DNA-Binding Proteins/blood , DNA-Binding Proteins/genetics , Eosinophils/metabolism , Eosinophils/pathology , Female , Gene Expression Regulation , Humans , London/epidemiology , Low Density Lipoprotein Receptor-Related Protein-2/blood , Low Density Lipoprotein Receptor-Related Protein-2/genetics , Male , Middle Aged , Oxidoreductases Acting on CH-CH Group Donors/blood , Oxidoreductases Acting on CH-CH Group Donors/genetics , Racial Groups , Receptors, Calcitriol/blood , Receptors, Calcitriol/genetics , Receptors, Cell Surface/blood , Receptors, Cell Surface/genetics , Respiratory Function Tests , Severity of Illness Index , Transcription Factors/blood , Transcription Factors/genetics , Vitamin D/blood , Vitamin D Deficiency/blood , Vitamin D Deficiency/complications , Vitamin D Deficiency/drug therapy
4.
Scientifica (Cairo) ; 2016: 6767538, 2016.
Article in English | MEDLINE | ID: mdl-27110427

ABSTRACT

Nematode volume and surface area are usually based on the inappropriate assumption that the animal is cylindrical. While nematodes are approximately circular in cross section, the radius varies longitudinally. We use standard morphometric data to obtain improved estimates of volume and surface area based on (i) a geometrical approach and (ii) a Bézier representation of the nematode. These new estimators require only the morphometric data available from Cobb's ratios, but if fewer coordinates are available the geometric approach reduces to the standard estimates. Consequently, these new estimators are better than the standard alternatives.

5.
Biol Psychol ; 108: 132-41, 2015 May.
Article in English | MEDLINE | ID: mdl-25869175

ABSTRACT

This study examined the existence of direct maternal-infant physiological relatedness in respiratory sinus arrhythmia (RSA) when the infant was age 1, 2, 4, 8, and 12 weeks. We instructed mothers to breathe at 6, 12, 15, 20, and 6 cycles per minute while their infants lay on their body. The mother-infant ECG and respiration were registered and video recordings were made. RR-interval (RRI), respiration rate (fR) and RSA were calculated and mother-infant RSA response-patterns were analyzed. The results revealed that infants adjusted their RSA levels to their mothers' levels during the first 2 months of life, but not at 3 months of age, which could be interpreted as a continuing intra-uterine effect. The attenuation between 2 and 3 months could be a reflection of the 2-month developmental shift of social orientation.


Subject(s)
Heart Rate/physiology , Respiratory Rate/physiology , Respiratory Sinus Arrhythmia/physiology , Adult , Child Development , Electrocardiography , Female , Humans , Infant , Infant, Newborn , Male , Maternal Behavior , Maternal-Fetal Relations , Mother-Child Relations , Mothers , Motor Activity/physiology , Sleep/physiology , Social Environment
6.
Thorax ; 70(5): 451-7, 2015 May.
Article in English | MEDLINE | ID: mdl-25724847

ABSTRACT

RATIONALE: Asthma exacerbations are commonly precipitated by viral upper respiratory infections (URIs). Vitamin D insufficiency associates with susceptibility to URI in patients with asthma. Trials of vitamin D in adults with asthma with incidence of exacerbation and URI as primary outcome are lacking. OBJECTIVE: To conduct a randomised controlled trial of vitamin D3 supplementation for the prevention of asthma exacerbation and URI (coprimary outcomes). MEASUREMENTS AND METHODS: 250 adults with asthma in London, UK were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 (n=125) or placebo (n=125) over 1 year. Secondary outcomes included asthma control test and St George's Respiratory Questionnaire scores, fractional exhaled nitric oxide and concentrations of inflammatory markers in induced sputum. Subgroup analyses were performed to determine whether effects of supplementation were modified by baseline vitamin D status or genotype for 34 single nucleotide polymorphisms in 11 vitamin D pathway genes. MAIN RESULTS: 206/250 participants (82%) were vitamin D insufficient at baseline. Vitamin D3 did not influence time to first severe exacerbation (adjusted HR 1.02, 95% CI 0.69 to 1.53, p=0.91) or first URI (adjusted HR 0.87, 95% CI 0.64 to 1.16, p=0.34). No clinically important effect of vitamin D3 was seen on any of the secondary outcomes listed above. The influence of vitamin D3 on coprimary outcomes was not modified by baseline vitamin D status or genotype. CONCLUSIONS: Bolus-dose vitamin D3 supplementation did not influence time to exacerbation or URI in a population of adults with asthma with a high prevalence of baseline vitamin D insufficiency. TRIAL REGISTRATION NUMBER: NCT00978315 (ClinicalTrials.gov).


Subject(s)
Asthma/complications , Asthma/prevention & control , Cholecalciferol/administration & dosage , Dietary Supplements , Respiratory Tract Infections/prevention & control , Vitamins/administration & dosage , Adult , Cohort Studies , Double-Blind Method , Drug Administration Schedule , Female , Humans , Incidence , Male , Middle Aged , Respiratory Tract Infections/epidemiology , Time Factors
7.
Lancet Respir Med ; 3(2): 120-130, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25476069

ABSTRACT

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) often have vitamin D deficiency, which is associated with increased susceptibility to upper respiratory infection-a major precipitant of exacerbation. Multicentre trials of vitamin D supplementation for prevention of exacerbation and upper respiratory infection in patients with COPD are lacking. We therefore investigated whether vitamin D3 (colecalciferol) supplementation would reduce the incidence of moderate or severe COPD exacerbations and upper respiratory infections. METHODS: We did a randomised, double-blind, placebo-controlled trial of vitamin D3 supplementation in adults with COPD in 60 general practices and four Acute National Health Service Trust clinics in London, UK. Patients were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 or placebo over 1 year in a 1:1 ratio using computer-generated permuted block randomisation. Participants and study staff were masked to treatment assignment. Coprimary outcomes were time to first moderate or severe exacerbation and first upper respiratory infection. Analysis was by intention to treat. A prespecified subgroup analysis was done to assess whether effects of the intervention on the coprimary outcomes were modified by baseline vitamin D status. This trial is registered with ClinicalTrials.gov, number NCT00977873. FINDINGS: 240 patients were randomly allocated to the vitamin D3 group (n=122) and placebo group (n=118). Vitamin D3 compared with placebo did not affect time to first moderate or severe exacerbation (adjusted hazard ratio 0·86, 95% CI 0·60-1·24, p=0·42) or time to first upper respiratory infection (0·95, 0·69-1·31, p=0·75). Prespecified subgroup analysis showed that vitamin D3 was protective against moderate or severe exacerbation in participants with baseline serum 25-hydroxyvitamin D concentrations of less than 50 nmol/L (0·57, 0·35-0·92, p=0·021), but not in those with baseline 25-hydroxyvitamin D levels of at least 50 nmol/L (1·45, 0·81-2·62, p=0·21; p=0·021 for interaction between allocation and baseline serum 25-hydroxyvitamin D status). Baseline vitamin D status did not modify the effect of the intervention on risk of upper respiratory infection (pinteraction=0·41). INTERPRETATION: Vitamin D3 supplementation protected against moderate or severe exacerbation, but not upper respiratory infection, in patients with COPD with baseline 25-hydroxyvitamin D levels of less than 50 nmol/L. Our findings suggest that correction of vitamin D deficiency in patients with COPD reduces the risk of moderate or severe exacerbation. FUNDING: UK National Institute for Health Research.


Subject(s)
Cholecalciferol/therapeutic use , Dietary Supplements , Pulmonary Disease, Chronic Obstructive/diet therapy , Vitamins/therapeutic use , Aged , Double-Blind Method , Female , Humans , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/blood , Pulmonary Disease, Chronic Obstructive/complications , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/etiology , Vitamin D/analogs & derivatives , Vitamin D/blood , Vitamin D Deficiency/blood , Vitamin D Deficiency/complications , Vitamin D Deficiency/diet therapy
8.
PLoS One ; 9(9): e106920, 2014.
Article in English | MEDLINE | ID: mdl-25207803

ABSTRACT

This study examined the effects of tonal and atonal music on respiratory sinus arrhythmia (RSA) in 40 mothers and their 3-month-old infants. The tonal music fragment was composed using the structure of a harmonic series that corresponds with the pitch ratio characteristics of mother-infant vocal dialogues. The atonal fragment did not correspond with a tonal structure. Mother-infant ECG and respiration were registered along with simultaneous video recordings. RR-interval, respiration rate, and RSA were calculated. RSA was corrected for any confounding respiratory and motor activities. The results showed that the infants' and the mothers' RSA-responses to the tonal and atonal music differed. The infants showed significantly higher RSA-levels during the tonal fragment than during the atonal fragment and baseline, suggesting increased vagal activity during tonal music. The mothers showed RSA-responses that were equal to their infants only when the infants were lying close to their bodies and when they heard the difference between the two fragments, preferring the tonal above the atonal fragment. The results are discussed with regard to music-related topics, psychophysiological integration and mother-infant vocal interaction processes.


Subject(s)
Arrhythmia, Sinus/psychology , Mother-Child Relations/psychology , Music/psychology , Pattern Recognition, Physiological/physiology , Respiratory Rate/physiology , Adult , Electrocardiography , Facial Expression , Female , Humans , Infant , Male , Mothers/psychology , Vagus Nerve/physiology , Video Recording
9.
Infant Ment Health J ; 35(3): 220-32, 2014.
Article in English | MEDLINE | ID: mdl-25798477

ABSTRACT

The present study introduces the concept of a mother-infant group therapy that makes use of music, singing, and moving to establish maternal-infant intersubjectivity. It was conducted in a residential mother-baby unit for mothers with postnatal depression and their infants over a 5-week period. Maternal-infant intersubjectivity of four dyads in relation to the group dynamics were microanalyzed for Sessions 1 and 5. We made within-session (i.e., beginning-middle-end) and between-session (Session 1 vs. Session 5) comparisons for the number of intersubjectivity moments (ISMs), total time of intersubjectivity (IST), and the mean duration of ISMs on a dyadic (i.e., own mother/infant involved) and a nondyadic level (i.e., own mother/infant not involved). In addition, three ISM levels (degree of group contribution) were distinguished. The results indicated a significant increase of ISMs/IST from Session 1 to Session 5. Within-session analyses showed that ISMs/IST significantly decreased through Session 1 and remained stable throughout Session 5. Intersubjectivity occurred mainly on ISM Level 1 during Session 1 and on ISM Level 3 during Session 5, suggesting increased dyadic autonomy and self-efficacy. The results are discussed in relation to the musical characteristics of mother-infant dyads, music improvisation techniques, group processes, and intersubjective development.


Subject(s)
Dance Therapy/methods , Depression, Postpartum/therapy , Mothers/psychology , Music Therapy/methods , Psychotherapy, Group/methods , Adult , Family , Female , Humans , Infant , Infant Behavior , Male , Mother-Child Relations , Young Adult
10.
Mol Biol Res Commun ; 3(1): 21-32, 2014 Mar.
Article in English | MEDLINE | ID: mdl-27843974

ABSTRACT

Even purified enzyme preparations are often heterogeneous. For example, preparations of aspartate aminotransferase or cytochrome oxidase can consist of several different forms of the enzyme. For this reason we consider how different the kinetics of the reactions catalysed by a mixture of forms of an enzyme must be to provide some indication of the characteristics of the species present. Based on the standard Michaelis-Menten model, we show that if the Michaelis constants (Km) of two isoforms differ by a factor of at least 20 the steady-state kinetics can be used to characterise the mixture. However, even if heterogeneity is reflected in the kinetic data, the proportions of the different forms of the enzyme cannot be estimated from the kinetic data alone. Consequently, the heterogeneity of enzyme preparations is rarely reflected in measurements of their steady-state kinetics unless the species present have significantly different kinetic properties. This has two implications: (1) it is difficult, but not impossible, to detect molecular heterogeneity using kinetic data and (2) even when it is possible, a considerable quantity of high quality data is required.

11.
J Parasitol ; 99(2): 332-6, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23043312

ABSTRACT

The infective larvae of Teladorsagia circumcincta have a protective sheath that is lost soon after they reach the rumen of the sheep (the definitive host). Incubation in vitro with 50 mM imidazole caused more than 75% of L3 T. circumcincta to begin exsheathing within 2 hr. The initiation of exsheathing was less likely at pH 6.2 than at pH 7.8. The apparent pKa of this process was 7.08, similar to that for the conversion of imidazolium(+) to imidazole. Both the extent and the initial rate of exsheathing initiation increased with imidazole concentration (the apparent K(1/2) was about 50 mM). The initial rate of exsheathing initiation was stimulated by lactose and maltose, but not by some other carbohydrates, and by propylamine and imidazole acetic acid, but not by histidine.


Subject(s)
Enzyme Inhibitors/pharmacology , Imidazoles/pharmacology , Trichostrongyloidea/drug effects , Animals , Larva/drug effects , Larva/physiology , Rumen/parasitology , Sheep , Sheep Diseases/parasitology , Trichostrongyloidea/physiology , Trichostrongyloidiasis/parasitology , Trichostrongyloidiasis/veterinary
12.
Parasitol Int ; 61(3): 487-92, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22562002

ABSTRACT

The initial rate of NH(3)/NH(4)(+) accumulation in a medium containing L(3) Teladorsagia circumcincta was 0.18-0.6 pmol h(-1) larva(-1), which increased linearly with larval density. However it appeared that the larva-generated external concentration of NH(3)/NH(4)(+) did not exceed about 130 µM. The rate of NH(3)/NH(4)(+) accumulation increased with temperature between 4 °C and 37 °C, declined with increasing pH or increasing external NH(3)/NH(4)(+) concentration and was not significantly affected by the concentration of the phosphate buffer or by exsheathing the larvae. We infer from these data that the efflux of NH(3)/NH(4)(+) is a diffusive process and that the secreted or excreted NH(3)/NH(4)(+) is generated enzymatically rather than dissociating from the surface of the nematode. The enzymatic source of the NH(3)/NH(4)(+) is yet to be identified. Since the concentration of NH(3)/NH(4)(+) in the rumen and abomasum is higher than 130 µM, it is unlikely that T. circumcincta contributes to it, but NH(3)/NH(4)(+) may be accumulated from the rumen fluid by the nematode.


Subject(s)
Ammonia/pharmacokinetics , Ostertagia/metabolism , Quaternary Ammonium Compounds/metabolism , Animals , Energy Metabolism , Hydrogen-Ion Concentration , Kinetics , Larva/enzymology , Permeability , Phosphates/metabolism , Temperature
13.
Parasitol Res ; 110(1): 449-58, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21732182

ABSTRACT

Lectin binding to carbohydrates on parasite surfaces has been investigated as a method of distinguishing adult worms, eggs and sheathed and exsheathed L3 of Teladorsagia circumcincta and Haemonchus contortus, economically important abomasal parasites in temperate climates. Both species were maintained as pure laboratory cultures of field isolates from New Zealand. Each of the four life cycle stages could be distinguished by the binding of at least one lectin: adult worms by Sambucus nigra agglutinin (SNA); eggs by peanut agglutinin (PNA), ConcavalinA and Lens culinaris agglutinin (LCA); exsheathed L3 by Griffonia simplicifolia-I lectin (GSL-I) and Lotus tetragonolobus lectin (LTL) and sheathed L3 by Aleuria aurantia lectin (AAL). The whole surface of both adult T. circumcincta and H. contortus strongly bound lectins specific for N-acetylglucosamine (GlcNAc), N-acetylgalactosamine (GalNAc), mannose and fucose, but the two species could be distinguished by SNA binding only to T. circumcincta. Eggs could be distinguished by the binding of mannose-specific PNA to H. contortus and GalNAc-specific LCA and PSA to T. circumcincta eggs. GalNAc, GlcNAc and mannose lectins bound to the cuticle and over the excretory pores of a large proportion of sheathed L3 of both species, but only the H. contortus surface had exposed fucose or sialic acid complexes. The distinguishing lectin for sheathed L3 was AAL, which did not bind to T. circumcincta, but bound weakly to the head region of all fresh H. contortus and to 50-90% after 3 months storage. The cuticle of exsheathed L3 was unresponsive to all 19 lectins, and any binding was restricted to the head and tail regions. L3 exsheathed after 2-4 months storage could be distinguished by the binding of GSL-I and LTL to H. contortus but not to T. circumcincta. Lectin binding could be a useful adjunct in identifying L3, but lacked the consistency to be definitive, whereas it could be further developed as a practical method of distinguishing parasitic nematodes at other stages in the life cycle, particularly the eggs.


Subject(s)
Lectins , Parasitology/methods , Staining and Labeling/methods , Trichostrongyloidea/chemistry , Trichostrongyloidea/classification , Animals , Fluorescence , Lectins/metabolism , New Zealand , Trichostrongyloidea/isolation & purification , Trichostrongyloidea/metabolism
14.
Article in English | MEDLINE | ID: mdl-21296180

ABSTRACT

Like other nematodes, both L(3) and adult Teladosagia circumcincta secrete or excrete NH(3)/NH(4)(+), but the reactions involved in the production are unclear. Glutamate dehydrogenase is a significant source NH(3)/NH(4)(+) in some species, but previous reports indicate that the enzyme is absent from L(3)Haemonchus contortus. We show that glutamate dehydrogenase was active in both L(3) and adult T. circumcincta. The apparent K(m)s of the L(3) enzyme differed from those of the adult enzyme, the most significant of these being the increase in the K(m) for NH(4)(+) from 18mM in L(3) to 49mM in adults. The apparent V(max) of the oxidative deamination reaction was greater than that of the reductive reaction in L(3), but this was reversed in adults. The activity of the oxidative reaction of the L(3) enzyme was not affected by adenine nucleotides, but that of the reductive reaction was stimulated significantly by either ADP or ATP. The L(3) enzyme was more active with NAD(+) than it was with NADP(+), although the activities supported by NADH and NADPH were similar at saturating concentrations. While the activity of the oxidative reaction was sufficient to account for the NH(3)/NH(4)(+) efflux we have previously reported, the reductive amination reaction was likely to be more active.


Subject(s)
Ammonia/metabolism , Glutamate Dehydrogenase/metabolism , Larva/enzymology , Ostertagia/enzymology , Adenosine Diphosphate/metabolism , Adenosine Triphosphate/metabolism , Amino Acid Sequence , Animals , Deamination , Haemonchus/enzymology , Kinetics , Molecular Sequence Data , Molecular Weight , NAD/metabolism , NADP/metabolism , Ostertagiasis/enzymology , Ostertagiasis/parasitology , Sequence Alignment , Substrate Specificity
15.
Gut ; 60(2): 153-5, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21051451

ABSTRACT

We present a case of a patient with sarcoidosis and who subsequently developed dysphagia for solids, and some difficulty in swallowing liquids. High-resolution manometry of the oesophagus showed absent peristalsis in the oesophageal body and incomplete relaxation of the lower oesophageal sphincter. The diagnosis of sarcoidosis with oesophageal involvement was made and treatment with prednisolone 30 mg OD initiated. The patient improved symptomatically and high-resolution manometry was repeated showing complete recovery of oesophageal peristalsis and a deeper relaxation of the lower oesophageal sphincter. This is thus the first description of high-resolution manometry in sarcoidosis-induced changes of the oesophagus and of the effect treatment has on these motility changes. Oesophageal involvement of sarcoidosis is extremely rare and only a few cases have been reported. The symptoms and manometric pattern of this disorder mimics that of achalasia. However, we show that treatment with prednisolone results in a completely disappearance of the symptoms of dysphagia and subsequently lead to a large improvement of oesophageal motility.


Subject(s)
Esophageal Achalasia/etiology , Esophageal Diseases/complications , Sarcoidosis/etiology , Adult , Esophageal Diseases/diagnosis , Esophageal Diseases/drug therapy , Esophageal Motility Disorders/etiology , Glucocorticoids/therapeutic use , Humans , Male , Prednisolone/therapeutic use , Sarcoidosis/diagnosis , Sarcoidosis/drug therapy
18.
Proc Natl Acad Sci U S A ; 106(26): 10775-80, 2009 Jun 30.
Article in English | MEDLINE | ID: mdl-19541629

ABSTRACT

Phenotypic modulation of airway smooth muscle (ASM) is an important feature of airway remodeling in asthma that is characterized by enhanced proliferation and secretion of pro-inflammatory chemokines. These activities are regulated by the concentration of free Ca(2+) in the cytosol ([Ca(2+)](i)). A rise in [Ca(2+)](i) is normalized by rapid reuptake of Ca(2+) into sarcoplasmic reticulum (SR) stores by the sarco/endoplasmic reticulum Ca(2+) (SERCA) pump. We examined whether increased proliferative and secretory responses of ASM from asthmatics result from reduced SERCA expression. ASM cells were cultured from subjects with and without asthma. SERCA expression was evaluated by western blot, immunohistochemistry and real-time PCR. Changes in [Ca(2+)](i), cell spreading, cellular proliferation, and eotaxin-1 release were measured. Compared with control cells from healthy subjects, SERCA2 mRNA and protein expression was reduced in ASM cells from subjects with moderately severe asthma. SERCA2 expression was similarly reduced in ASM in vivo in subjects with moderate/severe asthma. Rises in [Ca(2+)](i) following cell surface receptor-induced SR activation, or inhibition of SERCA-mediated Ca(2+) re-uptake, were attenuated in ASM cells from asthmatics. Likewise, the return to baseline of [Ca](i) after stimulation by bradykinin was delayed by approximately 50% in ASM cells from asthmatics. siRNA-mediated knockdown of SERCA2 in ASM from healthy subjects increased cell spreading, eotaxin-1 release and proliferation. Our findings implicate a deficiency in SERCA2 in ASM in asthma that contributes to its secretory and hyperproliferative phenotype in asthma, and which may play a key role in mechanisms of airway remodeling.


Subject(s)
Asthma/metabolism , Bronchi/metabolism , Sarcoplasmic Reticulum/enzymology , Asthma/pathology , Asthma/physiopathology , Blotting, Western , Bronchi/pathology , Bronchi/physiopathology , Calcium/metabolism , Cell Movement , Cell Proliferation , Cells, Cultured , Chemokine CCL11/metabolism , Female , Gene Expression Regulation, Enzymologic , Homeostasis , Humans , Immunohistochemistry , Interleukin-13/pharmacology , Male , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/metabolism , RNA Interference , Reverse Transcriptase Polymerase Chain Reaction , Sarcoplasmic Reticulum Calcium-Transporting ATPases
19.
Pulm Pharmacol Ther ; 22(5): 417-25, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19409504

ABSTRACT

Altered bronchial vascular reactivity and remodelling including angiogenesis are documented features of asthma and other chronic inflammatory airway diseases. Expansion of the bronchial vasculature under these conditions involves both functional (vasodilation, hyperperfusion, increased microvascular permeability, oedema formation, and inflammatory cell recruitment) and structural changes (tissue and vascular remodelling) in the airways. These changes in airway vascular reactivity and vascularisation have significant pathophysiological consequences, which are manifest in the clinical symptoms of airway disease. Airway vascular reactivity is regulated by a wide variety of neurotransmitters and inflammatory mediators. Similarly, multiple growth factors are implicated in airway angiogenesis, with vascular endothelial growth factor amongst the most important. Increasing attention is focused on the complex interplay between angiogenic growth factors, airway smooth muscle and the various collagen-derived fragments that exhibit anti-angiogenic properties. The balance of these dynamic influences in airway neovascularisation processes and their therapeutic implications is just beginning to be elucidated. In this review article, we provide an account of recent developments in the areas of vascular reactivity and airway angiogenesis in chronic airway diseases.


Subject(s)
Bronchial Arteries/physiopathology , Bronchial Diseases/physiopathology , Bronchial Hyperreactivity/physiopathology , Muscle, Smooth/blood supply , Muscle, Smooth/physiopathology , Neovascularization, Pathologic/metabolism , Angiogenesis Modulating Agents/metabolism , Bronchial Arteries/metabolism , Bronchial Arteries/pathology , Bronchial Hyperreactivity/pathology , Chronic Disease , Humans , Intercellular Signaling Peptides and Proteins/metabolism , Muscle, Smooth/pathology , Respiratory Tract Diseases/metabolism , Respiratory Tract Diseases/pathology , Respiratory Tract Diseases/physiopathology
20.
Am J Respir Crit Care Med ; 178(5): 460-8, 2008 Sep 01.
Article in English | MEDLINE | ID: mdl-18556625

ABSTRACT

RATIONALE: Airway remodeling in asthma involves accumulation of airway smooth muscle (ASM) and increased vascularity due to angiogenesis. Bronchial blood vessels and ASM are found in close proximity, and ASM releases multiple proinflammatory mediators, including vascular endothelial growth factor (VEGF). OBJECTIVES: We examined whether release of proangiogenic mediators is increased in ASM from subjects with asthma and whether this is translated to induction of angiogenesis. METHODS: Biopsy-derived ASM cells were cultured from 12 subjects with mild asthma, 8 with moderate asthma, and 9 healthy control subjects. Angiogenesis induced by cell-conditioned medium (CM) from ASM was evaluated in a tubule formation assay. Anti-CD31-labeled tubules were quantified by image analysis. Angiogenic factors in CM were quantified by antibody arrays and by enzyme-linked immunosorbent assay. MEASUREMENTS AND MAIN RESULTS: Induction of angiogenesis by CM from unstimulated ASM was increased in subjects with mild asthma (twofold) and moderate asthma (threefold), compared with healthy CM (P < 0.001). Levels of angiogenic factors (VEGF, angiopoietin [Ang]-1, angiogenin) were similarly elevated in CM from subjects with asthma compared with that from healthy subjects (P < 0.05), whereas antiangiogenic factors (endostatin, Ang-2) were unchanged. VEGF, Ang-1, and angiogenin in combination increased vascularity (twofold, P < 0.01) in cultured intact biopsies. Selective VEGF immunodepletion abolished enhanced tubule formation by CM from asthmatic ASM (P < 0.01), but CM depletion of Ang-1 or angiogenin had no effect. CONCLUSIONS: ASM cultured from subjects with mild or moderate asthma, but not from healthy control subjects, promotes angiogenesis in vitro. This proangiogenic capacity resides in elevated VEGF release and suggests that ASM regulates airway neovascularization in asthma.


Subject(s)
Angiogenesis Inducing Agents/metabolism , Angiogenic Proteins/metabolism , Asthma/physiopathology , Muscle, Smooth/metabolism , Neovascularization, Pathologic , Adult , Angiopoietin-1 , Bronchi/blood supply , Bronchi/pathology , Case-Control Studies , Cells, Cultured , Female , Humans , Male , Myocytes, Smooth Muscle/metabolism , Protein Array Analysis , Vascular Endothelial Growth Factor A/metabolism
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