Arginine decarboxylase which makes its appearance in Lathyrus sativus seedlings after 24 h of seed germination reaches its highest level around 5-7 days, the cotyledons containing about 60% of the ♅ total activity in the seedlings at day 5. The cytosol enzyme was purified 977-fold from whole seedlings by steps involving manganese chloride treatment, ammonium sulphate and acetone fractionations, positive adsorption on alumina C-gamma gel, DEAE-Sephadex chromatography followed by preparative disc gel electrophoresis. The enzyme was shown to be homogeneous by electrophoretic and immunological criteria, had a molecular weight of 220,000 and appears to be a hexamer with identical subunits. The optimal pH and temperature for the enzyme activity were 8.5 and 45 degrees C respectively. The enzyme follows typical Michaelis-Menten kinetics with a Km value of 1.73 mM for arginine. Though Mn2+ at lower concentrations stimulated the enzyme activity, there was no dependence of the enzyme on any metal for the activity. The arginine decarboxylase of L. sativus is a sulfhydryl enzyme. The data on co-factor requirement, inhibition by carbonyl reagents, reducing agents and pyridoxal phosphate inhibitors, and a partial reversal by pyridoxal phosphate of inhibition by pyridoxal-HCl suggests that pyridoxal 5'-phosphate is involved as a co-factor for the enzyme. The enzyme activity was inhibited competitively by various amines including the product agmatine. Highest inhibition was obtained with spermine and arcain. The substrate analogue, L-canavanine, homologue L-homoarginine and other basic amino acids like L-lysine and L-ornithine inhibited the enzyme activity competitively, homoarginine being the most effective in this respect.
The virostatic compound N,N-diethyl-4-[2-(2-oxo-3-tetradecyl-1-imidazolidinyl)-ethyl]-1-piperazinecarboxamide-hydrochloride (5531) was analyzed as to its effect on the induction of tryptophan-pyrrolase and tyrosineaminotransferase in rat liver. 1. The basic activity of the enzymes was not influenced by the substance either in normal or in adrenalectomized animals. 2. The induction of the enzymes by cortisone increased in the presence of the compound whereas the substrate induction remained unchanged. 3. The induction of tyrosine-aminotransferase by dexamethasonephosphate in tissue culture is inhibited if the dose of compound 5531 is higher than 5 mug/ml.
Enzymic properties of monoamine oxidase (MAO) in dog serum were studied and the following results were obtained. Some of enzymic properties of MAO in dog serum differed from that of mitochondrial MAO. When dog serum was fractionated by ammonium sulfate, proteins were concentrated in two fractions, such as 25 approximately 33% and 67 approximately 80% of saturated ammonium sulfate fraction, while MAO activity was concentrated in 40 approximately 50% of saturated ammonium sulfate fraction. The reaction rate of MAO in dog serum was found to be proportional to enzyme concentration. The optimum pH of MAO in dog serum was 7.0 which differed from that of MAO in rabbit serum (pH 8.0). Tris-HCl buffer strongly inhibited MAO activity in dog serum. When benzylamine was used as substrate, the highest activity was obtained compared with the other substrate used. The activities with butylamine, amylamine, beta-phenylethylamine and tyramine showed about 30% while tryptamine and serotonin showed 3 approximately 10% compared to that with benzymlamine as substrate. The value of pI50 of catron was about 3 X 10(-6) M and that of harmaline was about 3 X 10(-5) M, but pargyline did not inhibit MAO activity in dog serum at the concentration of 1 X 10(-4) M.
Certain properties of the rat liver cell nuclei NAD-glycohydrolase (EC 22.214.171.124) were investigated. It is established that its highest activity is at 37 degrees with activation energy equal to 9480 cal/M and with factor Q10 equal to 1.5. The enzyme pH optimum in 0.2 M tris acetate is equal to 6.5 and in 0.2 potassium phosphate - 7.5. It was shown that the enzyme manifests its strict specificity only with beta-NAD, and it hardly decomposes NADP without affecting NADH, NADPH and NMN. The apparent Km value of the enzyme with respect to NAD is established. Isonicotinic acid hydrazide, nicotinamide and to the less extent nicotinic acid inhibit the enzymatic activity of nuclei. EDTA, EGTA, p-CMB, mercaptoethanol do not cause any changes in the rat liver cells nuclei NADase activity.
Acidic proteins are usually resistant to complete enzymic hydrolysis. The increasing number of "unusual" amino acids, which are unstable to acid hydrolysis, makes it necessary to have a method of enzymic hydrolysis applicable to all proteins. The complete hydrolysis of four acidic proteins by subtilisin plus leucine amino-peptidase plus prolidase followed by carboxypeptidase C, is described. Recoveries of amino acids were in excellent agreement with the expected content from the known sequences.
BACKGROUND AND OBJECTIVE: A number of studies have shown that the +252A/G polymorphism (rs909253) in the lymphotoxin-α (LT-α) gene is implicated in susceptibility to asthma. However, the findings have been inconclusive. The aim of this study was to investigate the association between the +252A/G polymorphism in the LT-α gene and the risk of asthma by performing a meta-analysis.
METHODS: The Pubmed and Embase databases were searched for all studies relating to this polymorphism and the risk of asthma. Statistical analyses were performed using the Revman4.2 and STATA 10.0 software.
RESULTS: Thirteen case-control studies that included a total of 2220 cases and 6428 controls were included in the meta-analysis. There was no significant association between this polymorphism and the risk of asthma in the all-combined analysis (odds ratio (OR) 1.14, 95% confidence interval (CI): 0.89-1.45 for GG+GA vs AA). In a subgroup analysis by ethnicity, no significant association with asthma risk was identified in Asians (OR 1.31, 95% CI: 0.97-1.77) or Europeans (OR 1.08, 95% CI: 0.77-1.53). In a subgroup analysis by age, a significantly increased risk was identified among adults (OR 1.25, 95% CI: 1.03-1.50) but not children (OR 1.04, 95% CI: 0.28-3.89). In a subgroup analysis by atopic status, a significantly elevated risk was identified among atopic (OR 1.55, 95% CI: 1.28-1.87) but not non-atopic individuals (OR 0.94, 95% CI: 0.53-1.68).
CONCLUSIONS: This meta-analysis suggested that the +252A/G polymorphism in the LT-α gene is a risk factor for asthma in adults and atopic populations.
OBJECTIVES: To develop explicit and transparent recommendations on controversial asthma management issues in children and to illustrate the usefulness of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach in rating the quality of evidence and strength of recommendations.
METHODS: Health care questions were formulated for 3 controversies in clinical practice: what is the most effective treatment in asthma not under control with standard-dose inhaled corticosteroids (ICS; step 3), the use of leukotriene receptor antagonist for viral wheeze, and the role of extra fine particle aerosols. GRADE was used to rate the quality of evidence and strength of recommendations after performing systematic literature searches. We provide evidence profiles and considerations about benefit and harm, preferences and values, and resource use, all of which played a role in formulating final recommendations.
RESULTS: By applying GRADE and focusing on outcomes that are important to patients and explicit other considerations, our recommendations differ from those in other international guidelines. We prefer to double the dose of ICS instead of adding a long-acting β-agonist in step 3; ICS instead of leukotriene receptor antagonist are the first choice in preschool wheeze, and extra fine particle ICS formulations are not first-line treatment in children with asthma. Recommendations are weak and based on low-quality evidence for critical outcomes.
CONCLUSIONS: We provide systematically and transparently developed recommendations about controversial asthma management options. Using GRADE for guideline development may change recommendations, enhance guideline implementation, and define remaining research gaps.
Marked racial disparities exist in the prevalence, mortality, and treatment of asthma, between African American and White children and adolescents, despite increases in intervention trials to improve asthma outcomes. Yet, interventions to improve African American children's health must be culturally appropriate. To date, limited frameworks are available to decide whether an intervention tested with a targeted minority population employs a culturally appropriate design. In this article, we applied Bernal, Bonilla, and Bellido's ecological validity model to examine the cultural appropriateness of 12 randomized controlled trials of asthma self-management interventions published from 2000 to 2010. Most frequently met criteria were culturally appropriate methods of development and/or adaptation of interventions and inclusion of theoretical models. Least often met criteria were incorporating metaphors pertinent to participants and application of the language dimension. Based on this analysis, it is clear that an overarching framework is needed to guide the development of culturally targeted interventions.
BACKGROUND AND OBJECTIVES: Laser acupuncture has often been recommended as a treatment of asthma. The technique is noninvasive, and seems particularly suitable for children. However, the results from several clinical trials are contradictory. The objective of this review was to assess the effectiveness of laser acupuncture in the treatment of childhood asthma.
METHODS: Literature searches of electronic database were conducted in The Cochrane Library, Medline, EMBASE, AMED, CINAHL, and two Chinese literature databases (CNKI and VIP) up to February 2012. Randomized controlled trials (RCTs) testing laser acupuncture for asthma in children were included. No language restrictions were applied. Three authors independently selected articles, extracted data, and assessed trial quality.
RESULTS: Our searches identified 13 potential eligible studies, of which three with a total number of 176 patients met our inclusion criteria. The quality of included RCTs were low. One RCT with a parallel group design showed positive results, while two crossover RCTs generated negative results. There was variation in the type of patients, the interventions, and outcome measures. Because of the significant clinical and methodological heterogeneity, no meta-analysis was performed.
CONCLUSIONS: The number of RCTs and their total sample sizes are small; and their methodological quality is low. Therefore, no compelling evidence exists to suggest that laser acupuncture is not an effective treatment for childhood asthma. Further rigorous studies are warranted.
BACKGROUND: Because of concerns about the safety of long-acting β(2)-agonist (LABA) use in patients with asthma, withdrawal of the LABA is recommended by the US Food and Drug Administration once asthma is controlled by combination therapy with a LABA and inhaled corticosteroid (ICS).
OBJECTIVE: To perform a systematic review and meta-analysis assessing evidence supporting the discontinuation of LABA therapy once asthma control has been achieved with a combination of ICS and LABA.
DATA SOURCES: MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched (through August 2010), references of identified studies and selected narrative review articles were evaluated, registries of clinical trials were reviewed, and manufacturers of LABAs were contacted.
STUDY SELECTION: Randomized controlled trials of discontinuation of LABA therapy in patients with asthma controlled with a combination of ICS and LABA.
DATA EXTRACTION: Two reviewers independently screened each title and abstract in the initial searches and then the full text of each nominated article to extract data for analyses.
RESULTS: Of 1492 screened articles, only 5 trials involving patients aged 15 years or older fulfilled a priori–specified inclusion criteria. Results did not favor the LABA step-off approach compared with no change in treatment. The LABA step-off regimen increased asthma impairment, with worse Asthma Quality of Life Questionnaire score (mean difference [95% CI], 0.32 [0.14-0.51] points lower); worse Asthma Control Questionnaire score (0.24 [0.13-0.35] points higher); fewer symptom-free days (9.15% [1.62%-16.69%] less); and greater risk of withdrawal from study resulting from lack of efficacy or loss of asthma control (risk ratio, 3.27 [2.16-4.96]). Risk of exacerbations and deaths after LABA step-off were not evaluable because of the small number of events and short duration of follow-up.
CONCLUSIONS: Evidence suggests that discontinuing LABA therapy in adults and older children with asthma controlled with a combination of ICSs and LABAs results in increased asthma-associated impairment. Additional trials measuring all long-term patient-important outcomes are needed.
BACKGROUND: Although the health benefits of breastfeeding are widely acknowledged, opinions and recommendations are strongly divided on the optimal duration of exclusive breastfeeding. Since 2001, the World Health Organization has recommended exclusive breastfeeding for six months. Much of the recent debate in developed countries has centred on the micronutrient adequacy, as well as the existence and magnitude of health benefits, of this practice.
OBJECTIVES: To assess the effects on child health, growth, and development, and on maternal health, of exclusive breastfeeding for six months versus exclusive breastfeeding for three to four months with mixed breastfeeding (introduction of complementary liquid or solid foods with continued breastfeeding) thereafter through six months.
SEARCH METHODS: We searched The Cochrane Library (2011, Issue 6), MEDLINE (1 January 2007 to 14 June 2011), EMBASE (1 January 2007 to 14 June 2011), CINAHL (1 January 2007 to 14 June 2011), BIOSIS (1 January 2007 to 14 June 2011), African Index Medicus (searched 15 June 2011), Index Medicus for the WHO Eastern Mediterranean Region (IMEMR) (searched 15 June 2011), LILACS (Latin American and Caribbean Health Sciences) (searched 15 June 2011). We also contacted experts in the field.The search for the first version of the review in 2000 yielded a total of 2668 unique citations. Contacts with experts in the field yielded additional published and unpublished studies. The updated literature review in December 2006 yielded 835 additional unique citations.
SELECTION CRITERIA: We selected all internally-controlled clinical trials and observational studies comparing child or maternal health outcomes with exclusive breastfeeding for six or more months versus exclusive breastfeeding for at least three to four months with continued mixed breastfeeding until at least six months. Studies were stratified according to study design (controlled trials versus observational studies), provenance (developing versus developed countries), and timing of compared feeding groups (three to seven months versus later).
DATA COLLECTION AND ANALYSIS: We independently assessed study quality and extracted data.
MAIN RESULTS: We identified 23 independent studies meeting the selection criteria: 11 from developing countries (two of which were controlled trials in Honduras) and 12 from developed countries (all observational studies). Definitions of exclusive breastfeeding varied considerably across studies. Neither the trials nor the observational studies suggest that infants who continue to be exclusively breastfed for six months show deficits in weight or length gain, although larger sample sizes would be required to rule out modest differences in risk of undernutrition. In developing-country settings where newborn iron stores may be suboptimal, the evidence suggests that exclusive breastfeeding without iron supplementation through six months may compromise hematologic status. Based on the Belarusian study, six months of exclusive breastfeeding confers no benefit (versus three months of exclusive breastfeeding followed by continued partial breastfeeding through six months) on height, weight, body mass index, dental caries, cognitive ability, or behaviour at 6.5 years of age. Based on studies from Belarus, Iran, and Nigeria, however, infants who continue exclusive breastfeeding for six months or more appear to have a significantly reduced risk of gastrointestinal and (in the Iranian and Nigerian studies) respiratory infection. No significant reduction in risk of atopic eczema, asthma, or other atopic outcomes has been demonstrated in studies from Finland, Australia, and Belarus. Data from the two Honduran trials and from observational studies from Bangladesh and Senegal suggest that exclusive breastfeeding through six months is associated with delayed resumption of menses and, in the Honduran trials, more rapid postpartum weight loss in the mother.
AUTHORS' CONCLUSIONS: Infants who are exclusively breastfed for six months experience less morbidity from gastrointestinal infection than those who are partially breastfed as of three or four months, and no deficits have been demonstrated in growth among infants from either developing or developed countries who are exclusively breastfed for six months or longer. Moreover, the mothers of such infants have more prolonged lactational amenorrhea. Although infants should still be managed individually so that insufficient growth or other adverse outcomes are not ignored and appropriate interventions are provided, the available evidence demonstrates no apparent risks in recommending, as a general policy, exclusive breastfeeding for the first six months of life in both developing and developed-country settings.
BACKGROUND: Psychological therapies have been developed for parents of children and adolescents with a chronic illness. Such therapies include parent only or parent and child/adolescent, and are designed to treat parent behaviour, parent mental health, child behaviour/disability, child mental health, child symptoms and/or family functioning. No comprehensive, meta-analytic reviews have been published in this area.
OBJECTIVES: To evaluate the effectiveness of psychological therapies that include coping strategies for parents of children/adolescents with chronic illnesses (painful conditions, cancer, diabetes mellitus, asthma, traumatic brain injury, inflammatory bowel diseases, skin diseases or gynaecological disorders). The therapy will aim to improve parent behaviour, parent mental health, child behaviour/disability, child mental health, child symptoms and family functioning.
SEARCH METHODS: We searched CENTRAL, MEDLINE, EMBASE and PsycINFO for randomised controlled trials (RCTs) of psychological interventions that included parents of children and adolescents with a chronic illness. The initial search was from inception of these databases to June 2011 and we conducted a follow-up search from June 2011 to March 2012. We identified additional studies from the reference list of retrieved papers and from discussion with investigators.
SELECTION CRITERIA: Included studies were RCTs of psychological interventions that delivered treatment to parents of children and adolescents (under 19 years of age) with a chronic illness compared to active control, wait list control or treatment as usual. We excluded studies if the parent component was a coaching intervention, the aim of the intervention was health prevention/promotion, the comparator was a pharmacological treatment, the child/adolescent had an illness not listed above or the study included children with more than one type of chronic illness. Further to this, we excluded studies when the sample size of either comparator group was fewer than 10 at post-treatment.
DATA COLLECTION AND ANALYSIS: We included 35 RCTs involving a total of 2723 primary trial participants. Two review authors extracted data from 26 studies. We analysed data using two categories. First, we analysed data by each medical condition across all treatment classes at two time points (immediately post-treatment and the first available follow-up). Second, we analysed data by each treatment class (cognitive behavioural therapy (CBT), family therapy (FT), problem solving therapy (PST) and multisystemic therapy (MST)) across all medical conditions at two time points (immediately post-treatment and the first available follow-up). We assessed treatment effectiveness on six possible outcomes: parent behaviour, parent mental health, child behaviour/disability, child mental health, child symptoms and family functioning.
MAIN RESULTS: Across all treatment types, psychological therapies that included parents significantly improved child symptoms for painful conditions immediately post-treatment. Across all medical conditions, cognitive behavioural therapy (CBT) significantly improved child symptoms and problem solving therapy significantly improved parent behaviour and parent mental health immediately post-treatment. There were no other effects at post-treatment or follow-up. The risk of bias of included studies is described.
AUTHORS' CONCLUSIONS: There is no evidence on the effectiveness of psychological therapies that include parents in most outcome domains of functioning, for a large number of common chronic illnesses in children. There is good evidence for the effectiveness of including parents in psychological therapies that reduce pain in children with painful conditions. There is also good evidence for the effectiveness of CBT that includes parents for improving the primary symptom complaints when available data were included from chronic illness conditions. Finally, there is good evidence for the effectiveness of problem solving therapy delivered to parents on improving parent problem solving skills and parent mental health. All effects are immediately post-treatment. There are no significant findings for any treatment effects in any condition at follow-up.
The causes of adult-onset asthma are poorly established, and the asthmogenic role of air pollution has been investigated primarily in children. This review assesses the current evidence of the association between air pollution and asthma incidence among subjects free of asthma at least until late childhood. Seven publications from five study populations fulfilled the inclusion criteria (one case-control and six cohort studies). All but one used markers of local traffic-related air pollution to characterize long-term exposure. Those studies reported similar associations with traffic-related air pollution. However, protocols, definitions of asthma, and exposure assignment were rather heterogeneous, and three publications relied on the same study; thus we abstain from meta-analytic summaries. Reported patterns of effect modification (e.g., by sex, atopy, or smoking) were inconsistent. Overall, the role of traffic-related air pollution in adult-onset asthma is less conclusive than in childhood asthma. Larger studies with more consistent definitions of phenotypes and exposure assessment for local traffic-related pollutants (e.g., ultrafine particles) are needed. Pooling existing cohorts such as in the ongoing European ESCAPE and TRANSPHORM consortia are promising steps. There is, however, a need for large-scale megacohorts to investigate these effects in standardized ways and to identify the most susceptible populations.