510 research outputs found

    Postflask management of micropropagated bananas and plantains: A manual on how to handle tissue-cultured banana and plantain plants

    Get PDF
    Micropropagation techniques have the potential to deliver large amounts of propagules of vegetatively propagated plantain and banana, enabling the rapid dissemination of land races and new varieties resulting from breeding programs. However, a critical stage in the realization of this potential is postflask management, in order to rear the in vitro plantlets to a stage where field establishment is assured. This manual provides a stage-by-stage practical guide to postflask management beginning at the first stage of removal from the tissue culture facility through to the final stage of field establishment. The authors have drawn largely upon their own practical experience of this process, working in both lowland and mid-altitude humid environments. It is intended that this manual will be used by the technicians who are practically involved in the dissemination of plantain and banana germplasm

    Use of a Structured Mirrors Intervention Does Not Reduce Delirium Incidence But May Improve Factual Memory Encoding in Cardiac Surgical ICU Patients Aged Over 70 Years: A Pilot Time-Cluster Randomized Controlled Trial.

    Get PDF
    Introduction: Post-operative delirium remains a significant problem, particularly in the older surgical patient. Previous evidence suggests that the provision of supplementary visual feedback about ones environment via the use of a mirror may positively impact on mental status and attention (core delirium diagnostic domains). We aimed to explore whether use of an evidence-based mirrors intervention could be effective in reducing delirium and improving post-operative outcomes such as factual memory encoding of the Intensive Care Unit (ICU) environment in older cardiac surgical patients. Methods: This was a pilot time-cluster randomized controlled trial at a 32-bed ICU, enrolling 223 patients aged 70 years and over, admitted to ICU after elective or urgent cardiac surgery from October 29, 2012 to June 23, 2013. The Mirrors Group received a structured mirrors intervention at set times (e.g., following change in mental status). The Usual Care Group received the standard care without mirrors. Primary outcome was ICU delirium incidence; secondary outcomes were ICU delirium days, ICU days with altered mental status or inattention, total length of ICU stay, physical mobilization (balance confidence) at ICU discharge, recall of factual and delusional ICU memories at 12 weeks, Health-Related Quality of Life at 12 weeks, and acceptability of the intervention. Results: The intervention was not associated with a significant reduction in ICU delirium incidence [Mirrors: 20/115 (17%); Usual Care: 17/108 (16%)] or duration [Mirrors: 1 (1-3); Usual Care: 2 (1-8)]. Use of the intervention on ICU was predictive of significantly higher recall of factual (but not delusional) items at 12 weeks after surgery (p = 0.003) and acceptability was high, with clinicians using mirrors at 86% of all recorded hourly observations. The intervention did not significantly impact on other secondary outcomes. Conclusion: Use of a structured mirrors intervention on the post-operative ICU does not reduce delirium, but may result in improved factual memory encoding in older cardiac surgical patients. This effect may occur via mechanisms unrelated to delirium, altered mental status, or inattention. The intervention may provide a new means of improving outcomes in patients at risk of post-ICU anxiety and/or Post-Traumatic Stress Disorder. Trial Registration: Clinicaltrials.gov identifier NCT01599689

    IN VITRO RESCUE OF ZYGOTIC EMBRYOS FOR THE ENHANCEMENT OF HYBRID PLANTAIN (MUSA, AAB GROUP) PRODUCTION

    Get PDF
    Two sets of experiments were carried out to determine the seed production capacity of the French plantain cv. 'Bobby Tannap' and t

    Physiological and transcriptomic evidence for a close coupling between chloroplast ontogeny and cell cycle progression in the pennate diatom <i>Seminavis robusta</i>

    Get PDF
    Despite the growing interest in diatom genomics, detailed time series of gene expression in relation to key cellular processes are still lacking. Here, we investigated the relationships between the cell cycle and chloroplast development in the pennate diatom Seminavis robusta. This diatom possesses two chloroplasts with a well-orchestrated developmental cycle, common to many pennate diatoms. By assessing the effects of induced cell cycle arrest with microscopy and flow cytometry, we found that division and reorganization of the chloroplasts are initiated only after S-phase progression. Next, we quantified the expression of the S. robusta FtsZ homolog to address the division status of chloroplasts during synchronized growth and monitored microscopically their dynamics in relation to nuclear division and silicon deposition. We show that chloroplasts divide and relocate during the S/G2 phase, after which a girdle band is deposited to accommodate cell growth. Synchronized cultures of two genotypes were subsequently used for a cDNA-amplified fragment length polymorphism-based genome-wide transcript profiling, in which 917 reproducibly modulated transcripts were identified. We observed that genes involved in pigment biosynthesis and coding for light-harvesting proteins were up-regulated during G2/M phase and cell separation. Light and cell cycle progression were both found to affect fucoxanthin-chlorophyll a/c-binding protein expression and accumulation of fucoxanthin cell content. Because chloroplasts elongate at the stage of cytokinesis, cell cycle-modulated photosynthetic gene expression and synthesis of pigments in concert with cell division might balance chloroplast growth, which confirms that chloroplast biogenesis in S. robusta is tightly regulated

    Relationship between natural occurrence of banana streak badnavirus and symptom expression, relative concentration of viral antigen, and yield characteristics of some micropropagated Musa spp.

    Get PDF
    Micropropagated plants of 36 Musa genotypes with diverse genetic backgrounds, including 14 tetraploid plantain (TMPx) and banana (TMBx) hybrids, were evaluated for their response to banana streak badnavirus (BSV) infection under three environments from 1995 to 1997 in Nigeria. The characteristics evaluated were the natural incidence of BSV based on symptoms and virus indexing, relative concentration of BSV antigens in leaf tissues determined by ELISA, and some growth and yield descriptors. Virus occurrence and symptom expression, as well as the relative concentration of BSV antigens, fluctuated greatly between seasons during the cropping cycle, being high during the rainy season and low or negligible during the hot dry season. The natural incidence of plants with symptoms and BSV-infected plants varied between genotypes. Incidence of BSV on most International Institute of Tropical Agriculture (IITA) TMPx hybrids and three Fundación Hondureòa de Investigación Agrìcola (FHIA) hybrids was high in the three environments, with some variation. Most landraces and some FHIA or Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA) hybrids were not BSV-infected under either environment at Onne. However, a few expressed some foliar symptoms at Ibadan and indexed BSV positive. The relative concentration of BSV antigens in leaf samples was also high in most TMPx and some FHIA hybrids, but low in most landraces. While BSV infection had no significant effect on most growth characteristics, it had a highly variable effect on bunch weight loss among the genotypes. There was no relationship between the natural incidence of BSV, concentration of viral antigen and bunch weight loss among the 11 TMPx hybrids, three FHIA hybrids and three plantain landraces. Despite the high natural BSV incidence and the high relative antigen concentration in their leaf tissue, TMPx 548-9, TMPx 2637-49, TMPx 7002-1 and FHIA 21 suffered less than 15% bunch weight loss, and TMPx 548-4 and FHIA 22 suffered no loss. These results suggest that under the conditions specified in this study, these hybrids could be tentatively classified as ‘field tolerant’ to BS

    Chlamydia and gonorrhoea in pregnant Batswana women: time to discard the syndromic approach?

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Chlamydia and gonorrhoea are major causes of morbidity among women in developing countries. Both infections have been associated with pregnancy-related complications, and case detection and treatment in pregnancy is essential. In countries without laboratory support, the diagnosis and treatment of cervical infections is based on the syndromic approach. In this study we measured the prevalence of chlamydia and gonorrhoea among antenatal care attendees in Botswana. We evaluated the syndromic approach for the detection of cervical infections in pregnancy, and determined if risk scores could improve the diagnostic accuracy.</p> <p>Methods</p> <p>In a cross-sectional study, 703 antenatal care attendees in Botswana were interviewed and examined, and specimens were collected for the identification of <it>C trachomatis</it>, <it>N gonorrhoeae </it>and other reproductive tract infections. Risk scores to identify attendees with cervical infections were computed based on identified risk factors, and their sensitivities, specificities, likelihood ratios and predictive values were calculated.</p> <p>Results</p> <p>The prevalence of chlamydia was 8%, and gonorrhoea was found in 3% of the attendees. Symptoms and signs of vaginal discharge did not predict cervical infection, and a syndromic approach failed to identify infected women. Age (youth) risk factor most strongly associated with cervical infection. A risk score with only sociodemographic factors had likelihood ratios equivalent to risk scores which incorporated clinical signs and microscopy results. However, all the evaluated risk scores were of limited value in the diagnosis of chlamydia and gonorrhoea. A cut-off set at an acceptable sensitivity to avoid infected antenatal care attendees who remained untreated would inevitably lead to considerable over-treatment.</p> <p>Conclusion</p> <p>Although in extensive use, the syndromic approach is unsuitable for diagnosing cervical infections in antenatal care attendees in Botswana. None of the evaluated risk scores can replace this management. Without diagnostic tests, there are no adequate management strategies for <it>C trachomatis </it>and <it>N gonorrhoeae </it>in pregnant women in Botswana, a situation which is likely to apply to other countries in sub-Saharan Africa. Screening for cervical infections in pregnant women is an essential public health measure, and rapid tests will hopefully be available in developing countries within a few years.</p

    ENGOT-ov-6/TRINOVA-2: Randomised, double-blind, phase 3 study of pegylated liposomal doxorubicin plus trebananib or placebo in women with recurrent partially platinum-sensitive or resistant ovarian cancer

    Get PDF
    Aims: Trebananib, a peptide-Fc fusion protein, inhibits angiogenesis by inhibiting binding of angiopoietin-1/2 to the receptor tyrosine kinase Tie2. This randomised, double-blind, placebo-controlled phase 3 study evaluated whether trebananib plus pegylated liposomal doxorubicin (PLD) improved progression-free survival (PFS) in patients with recurrent epithelial ovarian cancer. / Methods: Women with recurrent ovarian cancer (platinum-free interval ≤12 months) were randomised to intravenous PLD 50 mg/m2 once every 4 weeks plus weekly intravenous trebananib 15 mg/kg or placebo. PFS was the primary end-point; key secondary end-points were objective response rate (ORR) and duration of response (DOR). Owing to PLD shortages, enrolment was paused for 13 months; the study was subsequently truncated. / Results: Two hundred twenty-three patients were enrolled. Median PFS was 7.6 months (95% CI, 7.2–9.0) in the trebananib arm and 7.2 months (95% CI, 4.8–8.2) in the placebo arm, with a hazard ratio of 0.92 (95% CI, 0.68–1.24). However, because the proportional hazards assumption was not fulfilled, the standard Cox model did not provide a reliable estimate of the hazard ratio. ORR in the trebananib arm was 46% versus 21% in the placebo arm (odds ratio, 3.43; 95% CI, 1.78–6.64). Median DOR was improved (trebananib, 7.4 months [95% CI, 5.7–7.6]; placebo, 3.9 months [95% CI, 2.3–6.5]). Adverse events with a greater incidence in the trebananib arm included localised oedema (61% versus 32%), ascites (29% versus 9%) and vomiting (45% versus 33%). / Conclusions: Trebananib demonstrated anticancer activity in this phase 3 study, indicated by improved ORR and DOR. Median PFS was not improved. No new safety signals were identified. / Trial registration: ClinicalTrials.gov, NCT0128125
    corecore