43 research outputs found

    A reproducible protocol for regeneration and transformation in canola (Brassica napus L.)

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    The objective of the present study is to develop an efficient protocol for shoot and plant regeneration using five commercial canola cultivars grown under the Egyptian agricultural conditions. The regeneration efficiency from hypocotyl explants was examined. The data indicated that embryonic calli were formed within two weeks in the presence of 1 mgl-1 2,4-D. Adventitious shoots emerged from the embryonic callus in the presence of 4.5 mgl-1 BA. The cultivars showed a varied response to shoot regeneration. Regeneration frequency was high in the cultivar Sarow-4 (68%) followed by Masrri L-16 (64%) compared with the other cultivars tested. Hypocotyl explants from the cultivars Sarow-4 and Semu-249 were inoculated and co-cultivated with Agrobacterium tumefaciens strain LBA4404 harboring a binary vector pBI-121 containing the neomycin phosphotransferase-II gene (NPT-II). The resulted putative transgenic plantlets were able to grow under knanamycin containing medium. The stable integration of the NPT-II gene into the plant genomes was tested by PCR using NPT-II -specific primers. The GUS gene expression can be detected only in the transgenic plants. The reported protocol in the present study is repeatable and can be used to regenerate transgenic canola plants expressing the genes present in A. tumifaciens binary vectors.Keywords: Agrobacterium, canola, GUS assay, regeneration, fransformation, NPT II gen

    Thymic Selection Determines γδ T Cell Effector Fate: Antigen-Naive Cells Make Interleukin-17 and Antigen-Experienced Cells Make Interferon γ

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    γδ T cells contribute uniquely to host immune competence, but how they do so remain unclear. Here, by analyzing T10/T22-specific γδ T cells in mice with different T10/T22 expression patterns, we find that encountering antigen in the thymus is neither required nor inhibitory for the development of these cells. Instead, ligand recognition determines which of two distinct functional subsets γδ T cells will become. When triggered through the TCR, lymphoid-γδ T cells that encounter ligand during development produce IFNγ, while those that develop in the absence of ligand make IL-17, a major inducer of granulopoiesis during inflammation. Indeed, we find large fractions of IL-17+ γδ T cells from the draining lymph nodes immediately after peptide/CFA immunization and days before the appearance of antigen specific IL-17+ αβ T cells. This suggests a critical role for γδ T cells as ‘initial providers’ of IL-17 in an inflammatory response to novel antigens

    Genotype Dependent Somatic Embryogenesis from Egyptian Rice Mature Zygotic Embryos

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    Abs tract: Seven agronomically and genetically different rice (Oryza sativa L.) c u lt iv a rs were compared for their capacity for callus induction and plant regene ra t io n from mature zygotic embryos . W hite embryonic calli were formed within three weeks in the pres ence of 3 mgl 2,4,D . T h e s o matic Giza 178 s howed high regeneration fre q u e ncy (39%) followed by Giza 175 (38%) where the cultivar H1 s howed the lowes t record (24%). The data obtained fro m t h e random amplified polymorphic DNA analys is s howed that a total of 45 DNA markers were detected among the s e v e n ric e cultivars of wh ich, 29 bands were polymorphic (64.4%) and can be cons idered as us eful RA PD markers for th e rice cultivars us ed. Based on the data obtained by RA PD analys is , it was pos s ible to dis c riminate between the different genotyp e s u s e d . Sixteen out of the twenty nine polymorphic RAPD markers generated were found to be genotype-specific. Thes e markers can be verified as being RAPD markers ass ociated with the rege n e ra t io n c a pacity in the s even rice genotypes. Genetic s tability in tis s uecultured rice plants was examined by randomly amplified polymorphic DNA (RA PD) an a ly s is . T he genetic s imilarity between the mother and the regenerated plants was hig h fo r Giza 178 (91%) and it w a s 87.5 and 82 for Giza 175 and Sakha 102 respectively. The cultivar Giza 178 proved t o b e a us eful genetic res ource with unique regeneration ability and can be us ed for efficient generation of trans genic rice plants

    Accessibility to biologics and its impact on disease activity and quality of life in patients with rheumatoid arthritis in Kuwait

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    Objective: Biologics are indicated in rheumatoid arthritis (RA) in case of persistent high disease activity despite conventional disease-modifying anti-rheumatic drugs (cDMARDs) or patients with contraindications to cDMARDs or poor prognostic factors. The purpose of this study was to compare the prescription rates of biologics in Kuwaiti and non-Kuwaiti patients and to assess whether this had an impact on disease activity and quality of life in RA patients. Methods: Data were extracted from the Kuwait Registry for Rheumatic Diseases. Adult patients who satisfied the ACR classification criteria for RA from four major hospitals in Kuwait were evaluated from February 2013 through May 2018. The treatment agents, disease activity, and quality of life of Kuwaiti patients were compared with non-Kuwaiti patients. Results: A total of 1651 RA patients were included; 806 (48.8%) were Kuwaiti patients. Among Kuwaiti patients, 62.5% were on biologic drugs in comparison with 14% of non-Kuwaiti patients. In comparison with non-Kuwaiti patients, Kuwaiti patients had significantly lower numbers of swollen joints (p < 0.001) and disease activity score-28 scores (p = 0.02) and less steroid use (p < 0.001) yet a significantly higher health assessment questionnaire-disability index (p < 0.001). Regression analysis showed that DAS-28 scores were significantly associated with the treatment type (p < 0.001) and that nationality was significantly predictive of the treatment type (p < 0.001). Conclusion: In the setting of easy accessibility to treatment for Kuwaiti patients, biologics were prescribed by rheumatologists at a higher rate than for non-Kuwaitis. This may explain the lower disease activity and the lower rate of steroid use in Kuwaiti patients than non-Kuwaitis. Key points: • Significant discrepancies in the rates of prescribing biologic therapies between KP and NKP in Kuwait were observed. • Several treatment outcomes were significantly better in the KP group than in the NKP group even after adjustment of confounding factors. • The poor access to biologic therapies was suggested to limit the effectiveness of RA treatments in the NKP group

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    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

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    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
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