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991.
Pigeaire Alix Abernethy Deborah Smith Penelope M. Simpson Kaylene Fletcher Natalie Lu Chin-Yi Atkins Craig A. Cornish Edwina 《Molecular breeding : new strategies in plant improvement》1997,3(5):341-349
Transgenic plants of Lupinus angustifolius L. (cvs. Unicrop and Merrit) were routinely generated using Agrobacterium-mediated gene transfer to shoot apices. The bar gene for resistance to phosphinothricin (PPT, the active ingredient of the herbicide Basta) was used as the selectable marker. After co-cultivation, the shoot apex explants were transferred onto a PPT-free regeneration medium and their tops were thoroughly wetted with PPT solution (2 mg/ml). The multiple axillary shoots developing from the shoot apices were excised onto a medium containing 20 mg/l PPT. The surviving shoots were transferred every second week onto fresh medium containing 20 mg/l PPT. At each transfer, the number of surviving shoots decreased, until it stabilized. Indeed, some of these chimeric shoots surviving the PPT selection, eventually produced new green healthier axillary shoots which could be transferred to soil. This whole process took from 5 to 9 months after co-cultivation. Average transformation frequencies of 2.8% for cv. Unicrop and of 0.4% for the commercial cultivar Merrit were achieved. Molecular analysis of T0, T1, and T2 generations demonstrated stable integration of the foreign gene into the plant genome and expression of the integrated gene. Transformed plants of the T1 and T2 generations were resistant in glasshouse trials where the herbicide Basta (0.1 mg/ml) was sprayed onto whole plants. These results demonstrate that Agrobacterium-mediated gene transfer to preorganised meristematic tissue combined with axillary regeneration can form the basis of a routine transformation system for legume crop species which are difficult to regenerate from other explants. 相似文献
992.
Charlotte Grossiord Sanna Sevanto Isaac Borrego Allison M. Chan Adam D. Collins Lee T. Dickman Patrick J. Hudson Natalie McBranch Sean T. Michaletz William T. Pockman Max Ryan Alberto Vilagrosa Nate G. McDowell 《Plant, cell & environment》2017,40(9):1861-1873
Disentangling the relative impacts of precipitation reduction and vapour pressure deficit (VPD) on plant water dynamics and determining whether acclimation may influence these patterns in the future is an important challenge. Here, we report sap flux density (FD), stomatal conductance (Gs), hydraulic conductivity (KL) and xylem anatomy in piñon pine (Pinus edulis) and juniper (Juniperus monosperma) trees subjected to five years of precipitation reduction, atmospheric warming (elevated VPD) and their combined effects. No acclimation occurred under precipitation reduction: lower Gs and FD were found for both species compared to ambient conditions. Warming reduced the sensibility of stomata to VPD for both species but resulted in the maintenance of Gs and FD to ambient levels only for piñon. For juniper, reduced soil moisture under warming negated benefits of stomatal adjustments and resulted in reduced FD, Gs and KL. Although reduced stomatal sensitivity to VPD also occurred under combined stresses, reductions in Gs, FD and KL took place to similar levels as under single stresses for both species. Our results show that stomatal conductance adjustments to high VPD could minimize but not entirely prevent additive effects of warming and drying on water use and carbon acquisition of trees in semi‐arid regions. 相似文献
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Amanda M Lambert Helen M Parretti Emma Pearce Malcolm J Price Mark Riley Ronan Ryan Natalie Tyldesley-Marshall Tuba Saygn Avar Gemma Matthewman Alexandra Lee Khaled Ahmed Maria Lisa Odland Christoph U. Correll Marco Solmi Tom Marshall 《PLoS medicine》2022,19(4)
BackgroundSevere mental illness (SMI; schizophrenia, bipolar disorders (BDs), and other nonorganic psychoses) is associated with increased risk of cardiovascular disease (CVD) and CVD-related mortality. To date, no systematic review has investigated changes in population level CVD-related mortality over calendar time. It is unclear if this relationship has changed over time in higher-income countries with changing treatments.Methods and findingsTo address this gap, a systematic review was conducted, to assess the association between SMI and CVD including temporal change. Seven databases were searched (last: November 30, 2021) for cohort or case–control studies lasting ≥1 year, comparing frequency of CVD mortality or incidence in high-income countries between people with versus without SMI. No language restrictions were applied. Random effects meta-analyses were conducted to compute pooled hazard ratios (HRs) and rate ratios, pooled standardised mortality ratios (SMRs), pooled odds ratios (ORs), and pooled risk ratios (RRs) of CVD in those with versus without SMI. Temporal trends were explored by decade. Subgroup analyses by age, sex, setting, world region, and study quality (Newcastle–Ottawa scale (NOS) score) were conducted. The narrative synthesis included 108 studies, and the quantitative synthesis 59 mortality studies (with (≥1,841,356 cases and 29,321,409 controls) and 28 incidence studies (≥401,909 cases and 14,372,146 controls). The risk of CVD-related mortality for people with SMI was higher than controls across most comparisons, except for total CVD-related mortality for BD and cerebrovascular accident (CVA) for mixed SMI. Estimated risks were larger for schizophrenia than BD. Pooled results ranged from SMR = 1.55 (95% confidence interval (CI): 1.33 to 1.81, p < 0.001), for CVA in people with BD to HR/rate ratio = 2.40 (95% CI: 2.25 to 2.55, p < 0.001) for CVA in schizophrenia. For schizophrenia and BD, SMRs and pooled HRs/rate ratios for CHD and CVD mortality were larger in studies with outcomes occurring during the 1990s and 2000s than earlier decades (1980s: SMR = 1.14, 95% CI: 0.57 to 2.30, p = 0.71; 2000s: SMR = 2.59, 95% CI: 1.93 to 3.47, p < 0.001 for schizophrenia and CHD) and in studies including people with younger age. The incidence of CVA, CVD events, and heart failure in SMI was higher than controls. Estimated risks for schizophrenia ranged from HR/rate ratio 1.25 (95% CI: 1.04 to 1.51, p = 0.016) for total CVD events to rate ratio 3.82 (95% CI: 3.1 to 4.71, p < 0.001) for heart failure. Incidence of CHD was higher in BD versus controls. However, for schizophrenia, CHD was elevated in higher-quality studies only. The HR/rate ratios for CVA and CHD were larger in studies with outcomes occurring after the 1990s. Study limitations include the high risk of bias of some studies as they drew a comparison cohort from general population rates and the fact that it was difficult to exclude studies that had overlapping populations, although attempts were made to minimise this.ConclusionsIn this study, we found that SMI was associated with an approximate doubling in the rate ratio of CVD-related mortality, particularly since the 1990s, and in younger groups. SMI was also associated with increased incidence of CVA and CHD relative to control participants since the 1990s. More research is needed to clarify the association between SMI and CHD and ways to mitigate this risk.Amanda Lambert and co-workers study associations between severe mental illness and cardiovascular disease outcomes over time. 相似文献
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Oleguer Plana-Ripoll Julie W. Dreier Natalie C. Momen Anders Prior Nanna Weye Preben Bo Mortensen Carsten B. Pedersen Kim Moesgaard Iburg Maria Klitgaard Christensen Thomas Munk Laursen Esben Agerbo Marianne G. Pedersen Jrgen Brandt Lise Marie Frohn Camilla Geels Jesper H. Christensen John J. McGrath 《PLoS medicine》2022,19(6)
BackgroundThe provision of different types of mortality metrics (e.g., mortality rate ratios [MRRs] and life expectancy) allows the research community to access a more informative set of health metrics. The aim of this study was to provide a panel of mortality metrics associated with a comprehensive range of disorders and to design a web page to visualize all results.Methods and findingsIn a population-based cohort of all 7,378,598 persons living in Denmark at some point between 2000 and 2018, we identified individuals diagnosed at hospitals with 1,803 specific categories of disorders through the International Classification of Diseases-10th Revision (ICD-10) in the National Patient Register. Information on date and cause of death was obtained from the Registry of Causes of Death. For each of the disorders, a panel of epidemiological and mortality metrics was estimated, including incidence rates, age-of-onset distributions, MRRs, and differences in life expectancy (estimated as life years lost [LYLs]). Additionally, we examined models that adjusted for measures of air pollution to explore potential associations with MRRs. We focus on 39 general medical conditions to simplify the presentation of results, which cover 10 broad categories: circulatory, endocrine, pulmonary, gastrointestinal, urogenital, musculoskeletal, hematologic, mental, and neurologic conditions and cancer. A total of 3,676,694 males and 3,701,904 females were followed up for 101.7 million person-years. During the 19-year follow-up period, 1,034,273 persons (14.0%) died. For 37 of the 39 selected medical conditions, mortality rates were larger and life expectancy shorter compared to the Danish general population. For these 37 disorders, MRRs ranged from 1.09 (95% confidence interval [CI]: 1.09 to 1.10) for vision problems to 7.85 (7.77 to 7.93) for chronic liver disease, while LYLs ranged from 0.31 (0.14 to 0.47) years (approximately 16 weeks) for allergy to 17.05 (16.95 to 17.15) years for chronic liver disease. Adjustment for air pollution had very little impact on the estimates; however, a limitation of the study is the possibility that the association between the different disorders and mortality could be explained by other underlying factors associated with both the disorder and mortality.ConclusionsIn this study, we show estimates of incidence, age of onset, age of death, and mortality metrics (both MRRs and LYLs) for a comprehensive range of disorders. The interactive data visualization site (https://nbepi.com/atlas) allows more fine-grained analysis of the link between a range of disorders and key mortality estimates.In a population-based study, Oleguer Plana-Ripoll and colleagues report on and develop an online resource to study mortality metrics and life expectancy associated with different health conditions among individuals living in Denmark. 相似文献
996.
Brady R. Wilkinson Qiang An Natalie Glass Aspen Miller John Davison Michael C. Willey 《The Iowa orthopaedic journal》2022,42(1):69
BackgroundFemoral fragility fractures are one of the most common injuries managed by orthopedic surgeons. Malnutrition influences the poor outcomes observed in this population. Our purpose was to assess the annual trends of malnutrition diagnosis and determine risk factors for malnutrition and complications in patients 65 years and older presenting with femoral fragility fractures. We hypothesized that malnutrition would increase the risk of postoperative wound infection, wound dehiscence, non-union, and mortality.MethodsThe PearlDiver database was reviewed from 2010 to 2020. Patients ≥ 65-years-old with femur fractures treated with operative fixation were identified by CPT code. A preoperative diagnosis of malnourished state was defined by ICD-9 and ICD-10 codes and patients were divided into malnourished and non-malnourished cohorts. Patients were tracked for one year following operative fixation of a femoral fragility fracture for the occurrence of infection, wound dehiscence, nonunion and mortality. The rates of these complications were compared between malnourished and nonmalnourished cohorts.ResultsThere were 178,283 total femoral fragility fractures identified in patients aged 65-years or older. The overall prevalence of malnutrition diagnosis in this geriatric population was 12.8%. Documented malnutrition in femoral fragility fractures increased from 1.6% to 32.9% from 2010-2020 (P<0.0001). Compared to patients without malnutrition, patients with malnutrition are at increased risk of mortality (OR 1.31, 95% CI 1.2558 – 1.3752, p < 0.0001), are more likely to develop a wound infection (OR 1.49; 95% CI 1.252 – 1.7626; p < 0.0001), more likely to have a wound dehiscence (OR 1.55; 95% CI 1.3416 – 1.7949; p < 0.0001), and more likely to develop non-union (1.89; 95% CI 1.6946 – 2.1095; p < 0.0001). Multiple demographic variables were associated with malnutrition diagnosis including higher age, higher Charlson Comorbidity Index, female sex, dementia, and institutionalization. Parkinson’s disease, feeding difficulty and institutionalization demographic variables had the highest risk of malnutrition.ConclusionThe current study found that malnutrition diagnosis significantly increases the risk of adverse medical events in elderly adults with femoral fragility fractures. The rates of malnutrition increased steadily from 2010-2020. This trend is likely a result of increased awareness and testing for malnutrition, not reflecting an actual increased prevalence of malnutrition. Multiple expected demographic variables are associated with diagnosis of malnutrition. Level of Evidence: III 相似文献
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PGC-1-related coactivator (PRC), a growth-regulated member of the PGC-1 coactivator family, contributes to the expression of the mitochondrial respiratory apparatus. PRC also orchestrates a robust response to metabolic stress by promoting the expression of multiple genes specifying inflammation, proliferation, and metabolic reprogramming. Here, we demonstrate that this PRC-dependent stress program is activated during apoptosis and senescence, two major protective mechanisms against cellular dysfunction. Both PRC and its targets (IL1α, SPRR2D, and SPRR2F) were rapidly induced by menadione, an agent that promotes apoptosis through the generation of intracellular oxidants. Menadione-induced apoptosis and the PRC stress program were blocked by the antioxidant N-acetylcysteine. The PRC stress response was also activated by the topoisomerase I inhibitor 7-ethyl-10-hydroxycamptothecin (SN-38), an inducer of premature senescence in tumor cells. Cells treated with SN-38 displayed morphological characteristics of senescence and express senescence-associated β-galactosidase activity. In contrast to menadione, the SN-38 induction of the PRC program occurred over an extended time course and was antioxidant-insensitive. The potential adaptive function of the PRC stress response was investigated by treating cells with meclizine, a drug that promotes glycolytic energy metabolism and has been linked to cardio- and neuroprotection against ischemia-reperfusion injury. Meclizine increased lactate production and was a potent inducer of the PRC stress program, suggesting that PRC may contribute to the protective effects of meclizine. Finally, c-MYC and PRC were coordinately induced under all conditions tested, implicating c-MYC in the biological response to metabolic stress. The results suggest a general role for PRC in the adaptive response to cellular dysfunction. 相似文献