51 research outputs found
Pathobiology of Heterobasidion-conifer tree interaction : molecular analysis of antimicrobial peptide genes (Sp-AMPs)
Little information is available concerning the interaction of Heterobasidion annosum with the roots of herbaceous angiosperm plants. We investigated the infec¬tion biology of H. annosum during challenge with the angi¬osperm model Arabidopsis and monitored the host response after exposure to various hormone elicitors, chemicals (chitin, glucan and chitosan) and fungal species. This necrotrophic pathogen of conifer trees was able to infect the Col-8 (Columbia) ecotype of Arabidopsis in laboratory inoculation experiments. The germi¬nated H. annosum spores had appressorium-like penetra¬tion structures that attached to the surface of the Arabidopsis roots. The subsequent invasive fungal growth led to the disin¬tegration of the vascular region of the root tissues. The progres¬sion of root rot symptoms in Arabidopsis was similar to the infection development that was previously documented in Scots pine seedlings. Analysis of defensin gene expression in response to various biotic and chemical treatments in Scots pine compared with Arabidopsis suggested functional differences in their regulation in the two studied hosts.
In parallel to the above study, the expression patterns of other closely related proteins, Scots pine antimicrobial proteins (Sp-AMPs) and the structure and function of the encoded proteins were investigated. The Sp-AMPs exhibited increased levels of expression specifically when challenged with H. annosum, consistent with a function in conifer tree defenses. The Sp-AMPs were up-regulated after treatment with salicylic acid (SA) and with ethylene (ET). The Sp-AMPs possessed antifungal activity against H. annosum and caused morphological changes in its hyphae and spores. The Sp-AMPs directly bind soluble and insoluble β-(1,3)-glucans specifically and with high affinity. Furthermore, the addition of exogenous glucan is associated with increased levels of Sp-AMP expression in the conifer tree. It was concluded from Homology modeling and sequence comparisons that Sp-AMPs belong to a new family of antimicrobial proteins (PR-19) that are likely to act by binding the glucans, which are a major component of fungal cell walls.
To evaluate the potential of Sp-AMP as a molecular marker for resistance tree breeding, we developed transgenic tobacco plants expressing the Sp-AMP gene. A bioassay of transgenic tobacco (Nicotiana tabacum L. cv. SR1) plants over-expressing Sp-AMP2 challenged with the necrotrophic tobacco pathogen Botrytis cinerea was further investigated. The necrotic lesions caused by B. cinerea on the non-transgenic tobacco leaves were severe and larger than those lesions formed on the transgenic line. The results suggest that Scots pine pathogenesis-related protein 19 (PR-19) confers increased tolerance against Botrytis cineria in transgenic tobacco. This study provided insight concerning the initial molecular characterization of the expression and regulation of this protein family. The potential utility of the Sp-AMP genes as resistance markers in the conifer tree H. annosum pathosystem merits further investigation.Antimikrobiaalisten peptidien merkitys juurikäävän ja havupuiden vuorovaikutuksessa
Männynjuurikääpä (Heterobasidion annosum) on erityisesti havupuiden taudinaiheuttajana tunnettu sieni, mutta sen kykyä levitä koppisiemenisiin ruohovartisiin kasveihin ei ole juurikaan tutkittu. Sienen tartuntabiologiaa tutkittiin lituruoholla (Arabidopsis thaliana), jonka vastetta testattiin erilaisilla herätemolekyyleillä: hormoneilla, kemikaaleilla (kitiini, glukaani, kitosaani) sekä sienirihmastolla.
Juurikäävän rihmasto pystyi leviämään Col-8 tyypin lituruohoon. Sieni muodosti lituruohon juuriin painerihman kaltaisia rakenteita, joilla sienet tunkeutuvat kasvin solukkoon. Sieni vaurioitti juurten johtosolukkoa. Juurilahon oireet lituruoholla muistuttivat männyntaimilla havaittuja oireita. Defensiinigeenien toimintaa tutkittiin analysoimalla geenien ilmentymistä erilaisten bioottisten ja kemiallisten tekijöiden vaikutuksesta. Männyn geeni PsDef1 ja lituruohon geenit DEFLs (AT5G44973.1) ja PDF1.2 indusoituivat rihmaston tartunnan alkuvaiheissa. Geenien ilmentymiserot viittasivat kuitenkin siihen, että niiden säätely tapahtuu eri tavoin eri kasviryhmissä.
Sp-AMP ilmentyi erityisesti juurikäävän rihmaston vaikutuksesta, mutta tautia aiheuttamattomat sienet eivät saaneet aikaan samanlaista vaikutusta. Sp-AMP- geenin ilmentyminen lisääntyi heräteyhdisteinä tunnettujen salisyylihapon ja etyleenin vaikutuksesta. Sp-AMP proteiinit häiritsivät juurikäävän rihmaston kasvua. Proteiinit sitoutuivat liukoisiin ja liukenemattomiin β-(1,3)-glukaaneihin. Lisäksi eksogeenisen glukaanin kohonnut taso männyssä on kytköksissä korkeaan Sp-AMP geenin ilmentymistasoon. Homologian mallintamisen ja sekvenssien perusteella Sp-AMP proteiiniin pinnalla on hiilihydraattien sitoutumisalue. Sp-AMP proteiinit kuuluvat uuteen antimikrobiaalisten proteiinien ryhmään (PR-19), jotka sitoutuvat sienten soluseinien glukaaneihin.
Sp-AMP-geenin merkitystä taudinkestävyydessä tutkittiin tartuttamalla harmaahomesienellä (Botrytis cinerea) siirtogeeninen tupakkakasvi (Nicotiana tabacum SR1), joka ilmentää Sp-AMP-geeniä. Harmaahomeen aiheuttamat vauriot olivat vakavampia ei-siirtogeenisillä kasveilla. Tulosten perusteella männyn PR-proteiini 19 lisäsi siirtogeenisen tupakan harmaahomeenkestävyyttä.
Tutkimus toi molekulaarista lisätietoa tämän proteiiniryhmän ilmentämiseen ja säätelyyn kasveissa. Väitöskirjatyön tulokset antavat aihetta jatkotutkimuksille, sillä ne viittaavat siihen, että Sp-AMP- geenillä on lupaavia käyttömahdollisuuksia havupuiden taudinkestävyyden merkkigeeninä
A Gene Encoding Scots Pine Antimicrobial Protein Sp-AMP2 (PR-19) Confers Increased Tolerance against Botrytis cinerea in Transgenic Tobacco
Both the establishment of sustainable forestry practices and the improvement of commercially grown trees require better understanding of mechanisms used by forest trees to combat microbial pathogens. We investigated the contribution of a gene encoding Scots pine (Pinus sylvestris L.) antimicrobial protein Sp-AMP2 (PR-19) to the host defenses to evaluate the potential of Sp-AMP genes as molecular markers for resistance breeding. We developed transgenic tobacco plants expressing the Sp-AMP2 gene. Transgenic plants showed a reduction in the size of lesions caused by the necrotrophic pathogen Botrytis cinerea. In order to investigate Sp-AMP2 gene expression level, four transgenic lines were tested in comparison to control and non-transgenic plants. No Sp-AMP2 transcripts were observed in any of the control and non-transgenic plants tested. The transcript of Sp-AMP2 was abundantly present in all transgenic lines. Sp-AMP2 was induced highly in response to the B. cinerea infection at 3 d.p.i. This study provides an insight into the role of Sp-AMP2 and its functional and ecological significance in the regulation of plant–pathogen interactions.Peer reviewe
Особливості трудового виховання і профорієнтації в умовах нової парадигми освіти
(uk) У статті розкривається проблема формування майбутнього учителя-предметника, готового до забезпечення трудового виховання у професійній діяльності у світлі нової освітньої парадигми
Development of roundabout delay models using traffic simulation programs: a case study at Al-Mansour City, Iraq
Due to the increased number of vehicles, shopping centers and rapid growth population of Al-Mansour city, daily trips have been increasing besides generating traffic congestion in major roundabouts in the city. Those will make developing an imperial delay model in roundabouts important due to the traffic and geometric influences. Therefore, two major roundabouts have been selected in the city to be taken as a case study. Geometric features for the selected roundabouts have been measured accurately by satellite images via ArcGIS. Traffic and geometric data analysis indicate that both are significantly important on delay models. The delay time produced by SIDRA and SYNCHRO has been compared with the delay time measured from the field. A significant difference in delay for roundabouts is noticed. This difference could be attributed to the difference in driver behaviour. Ideal saturation flow is the main factor related to driver behaviour, so it adjusted to be the average of the saturation flow measured from the field (2200 vphgpl)
Activation of defence pathways in Scots pine bark after feeding by pine weevil (Hylobius abietis)
Background: During their lifetime, conifer trees are exposed to numerous herbivorous insects. To protect themselves against pests, trees have developed a broad repertoire of protective mechanisms. Many of the plant's defence reactions are activated upon an insect attack, and the underlying regulatory mechanisms are not entirely understood yet, in particular in conifer trees. Here, we present the results of our studies on the transcriptional response and the volatile compounds production of Scots pine (Pinus sylvestris) upon the large pine weevil (Hylobius abietis) feeding. Results: Transcriptional response of Scots pine to the weevil attack was investigated using a novel customised 36.4 K Pinus taeda microarray. The weevil feeding caused large-scale changes in the pine transcriptome. In total, 774 genes were significantly up-regulated more than 4-fold (p = 0.05), whereas 64 genes were significantly down-regulated more than 4-fold. Among the up-regulated genes, we could identify genes involved in signal perception, signalling pathways, transcriptional regulation, plant hormone homeostasis, secondary metabolism and defence responses. The weevil feeding on stem bark of pine significantly increased the total emission of volatile organic compounds from the undamaged stem bark area. The emission levels of monoterpenes and sesquiterpenes were also increased. Interestingly, we could not observe any correlation between the increased production of the terpenoid compounds and expression levels of the terpene synthase-encoding genes. Conclusions: The obtained data provide an important insight into the transcriptional response of conifer trees to insect herbivory and illustrate the massive changes in the host transcriptome upon insect attacks. Moreover, many of the induced pathways are common between conifers and angiosperms. The presented results are the first ones obtained by the use of a microarray platform with an extended coverage of pine transcriptome (36.4 K cDNA elements). The platform will further facilitate the identification of resistance markers with the direct relevance for conifer tree breeding.Peer reviewe
Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis
BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study
Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world.
Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231.
Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001).
Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries
Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
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