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1.
Plant Physiol ; 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34636903

RESUMO

GIGANTEA (GI) genes have a central role in plant development and influence several processes. Hybrid aspen T89 (Populus tremula x tremuloides) trees with low GI expression engineered through RNAi show severely compromised growth. To study the effect of reduced GI expression on leaf traits with special emphasis on leaf senescence, we grafted GI-RNAi scions onto wild-type rootstocks and successfully restored growth of the scions. The RNAi line had a distorted leaf shape and reduced photosynthesis, probably caused by modulation of phloem or stomatal function, increased starch accumulation, a higher carbon-to-nitrogen ratio, and reduced capacity to withstand moderate light stress. GI-RNAi also induced senescence under long day (LD) and moderate light conditions. Furthermore, the GI-RNAi lines were affected in their capacity to respond to "autumn environmental cues" inducing senescence, a type of leaf senescence that has physiological and biochemical characteristics that differ from those of senescence induced directly by stress under LD conditions. Overexpression of GI delayed senescence under simulated autumn conditions. The two different effects on leaf senescence under LD or simulated autumn conditions were not affected by the expression of FLOWERING LOCUS T. GI expression regulated leaf senescence locally-the phenotype followed the genotype of the branch, independent of its position on the tree-and trees with modified gene expression were affected in a similar way when grown in the field as under controlled conditions. Taken together, GI plays a central role in sensing environmental changes during autumn and determining the appropriate timing for leaf senescence in Populus.

2.
Plant J ; 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34624161

RESUMO

Boreal conifers possess a tremendous ability to survive and remain evergreen during harsh winter conditions and resume growth during summer. This is enabled by coordinated regulation of major cellular functions at the level of gene expression, metabolism, and physiology. Here we present a comprehensive characterization of the annual changes in the global transcriptome of Norway spruce (Picea abies) needles as a resource to understand needle development and acclimation processes throughout the year. In young, growing needles (May 15 until June 30), cell walls, organelles, etc., were formed, and this developmental program heavily influenced the transcriptome, explained by over-represented Gene Ontology (GO) categories. Later changes in gene expression were smaller but four phases were recognized: summer (July-August), autumn (September-October), winter (November-February), and spring (March-April), where over-represented GO categories demonstrated how the needles acclimated to the various seasons. Changes in the seasonal global transcriptome profile were accompanied by differential expression of members of the major transcription factor families. We present a tentative model of how cellular activities are regulated over the year in needles of Norway spruce, which demonstrates the value of mining this dataset, accessible in ConGenIE together with advanced visualization tools.

3.
Bio Protoc ; 11(17): e4144, 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34604449

RESUMO

Photosynthesis is the main process by which sunlight is harvested and converted into chemical energy and has been a focal point of fundamental research in plant biology for decades. In higher plants, the process takes place in the thylakoid membranes where the two photosystems (PSI and PSII) are located. In the past few decades, the evolution of biophysical and biochemical techniques allowed detailed studies of the thylakoid organization and the interaction between protein complexes and cofactors. These studies have mainly focused on model plants, such as Arabidopsis, pea, spinach, and tobacco, which are grown in climate chambers even though significant differences between indoor and outdoor growth conditions are present. In this manuscript, we present a new mild-solubilization procedure for use with "fragile" samples such as thylakoids from conifers growing outdoors. Here, the solubilization protocol is optimized with two detergents in two species, namely Norway spruce (Picea abies) and Scots pine (Pinus sylvestris). We have optimized the isolation and characterization of PSI and PSII multimeric mega- and super-complexes in a close-to-native condition by Blue-Native gel electrophoresis. Eventually, our protocol will not only help in the characterization of photosynthetic complexes from conifers but also in understanding winter adaptation.

4.
J Diabetes Complications ; 35(10): 107996, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34389234

RESUMO

AIM: SGLT2 inhibitors have been shown to reduce cardiovascular and renal complications in type 2 diabetes (T2D) patients at high cardiovascular risk. Metformin is currently widely used as initial monotherapy in T2D but lacks convincing data to show that it reduces risk of complications. We aim to compare the SGLT2 inhibitor dapagliflozin and metformin as first-line T2D medication with regard to development of complications in a registry-based randomised controlled trial. METHODS: The SGLT2 inhibitor or metformin as standard treatment of early stage type 2 diabetes (SMARTEST) trial will enrol 4300 subjects at 30-40 study sites in Sweden who will be randomised 1:1 to either metformin or dapagliflozin. Participants must have T2D duration <4 years, no prior cardiovascular disease, and be either drug-naïve or on monotherapy for T2D. RESULTS: The primary endpoint is a composite of all-cause death, major adverse cardiovascular events and occurrence or progression of microvascular complications (retinopathy, nephropathy, diabetic foot lesions). Secondary endpoints include individual components of the primary endpoint, start of insulin therapy, risk factor biomarkers, patient-reported outcome measures, and cost-effectiveness analysis. Outcomes will primarily be assessed using nationwide healthcare registries. CONCLUSIONS: The SMARTEST trial will investigate whether dapagliflozin is superior to metformin in preventing complications in early stage T2D. (Clinicaltrials.gov identifier NCT03982381, EudraCT 2019-001046-17).

5.
Mol Biol Evol ; 38(11): 5034-5050, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34329481

RESUMO

Understanding local adaptation has become a key research area given the ongoing climate challenge and the concomitant requirement to conserve genetic resources. Perennial plants, such as forest trees, are good models to study local adaptation given their wide geographic distribution, largely outcrossing mating systems, and demographic histories. We evaluated signatures of local adaptation in European aspen (Populus tremula) across Europe by means of whole-genome resequencing of a collection of 411 individual trees. We dissected admixture patterns between aspen lineages and observed a strong genomic mosaicism in Scandinavian trees, evidencing different colonization trajectories into the peninsula from Russia, Central and Western Europe. As a consequence of the secondary contacts between populations after the last glacial maximum, we detected an adaptive introgression event in a genome region of ∼500 kb in chromosome 10, harboring a large-effect locus that has previously been shown to contribute to adaptation to the short growing seasons characteristic of Northern Scandinavia. Demographic simulations and ancestry inference suggest an Eastern origin-probably Russian-of the adaptive Nordic allele which nowadays is present in a homozygous state at the north of Scandinavia. The strength of introgression and positive selection signatures in this region is a unique feature in the genome. Furthermore, we detected signals of balancing selection, shared across regional populations, that highlight the importance of standing variation as a primary source of alleles that facilitate local adaptation. Our results, therefore, emphasize the importance of migration-selection balance underlying the genetic architecture of key adaptive quantitative traits.

6.
N Biotechnol ; 64: 27-36, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34048978

RESUMO

Genetically modified hybrid aspens (Populus tremula L. x P. tremuloides Michx.), selected for increased growth under controlled conditions, have been grown in highly replicated field trials to evaluate how the target trait (growth) translated to natural conditions. Moreover, the variation was compared among genotypes of ecologically important non-target traits: number of shoots, bud set, pathogen infection, amount of insect herbivory, composition of the insect herbivore community and flower bud induction. This variation was compared with the variation in a population of randomly selected natural accessions of P. tremula grown in common garden trials, to estimate how the "unintended variation" present in transgenic trees, which in the future may be commercialized, compares with natural variation. The natural variation in the traits was found to be typically significantly greater. The data suggest that when authorities evaluate the potential risks associated with a field experiment or commercial introduction of transgenic trees, risk evaluation should focus on target traits and that unintentional variation in non-target traits is of less concern.

7.
Obes Sci Pract ; 7(1): 4-13, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33680487

RESUMO

Objective: Obesity is associated with reduced health-related quality of life (HRQoL). Outcomes of nonsurgical weight loss treatment on HRQoL are inconsistent and it is unclear how much weight reduction, or what type of treatment, is required for significant improvements. This study aimed to evaluate the effects of a lifestyle intervention program on weight, eating behaviors, and HRQoL, and to describe participants' experiences of treatment. Methods: This 2-year intervention trial in persons with class II or III obesity comprised a 3-month liquid low-energy diet (880 kcal/d) followed by a 3-month reintroduction to regular foods, combined with behavioral group treatment. Results: Fifty-five participants (73% women) were included, mean (SD) age 43.2 (12.4) years, and mean body mass index 42.0 (6.0) kg/m2. Mean weight loss at 6, 12, and 24 months was 18.9%, 13.7%, and 7.2%, respectively. Short- and long-term effects on eating behavior were favorable. Twelve of 14 HRQoL domains were improved at 6 months, compared to eight domains at 12 months. After 24 months, 2 of 14 domains, physical and psychosocial functioning, were improved. The treatment program was well accepted by the participants. Conclusions: Substantial weight loss after 6 months was associated with extensive improvements in HRQoL, comprising the physical, psychosocial, and mental domains. Significant weight regain was observed between 6 and 24 months follow-up. Modest weight loss after 24 months was associated with moderate improvement in physical functioning and large improvement in psychosocial functioning. The effect on psychosocial functioning is most likely related to both weight loss and behavioral treatment.

9.
Lakartidningen ; 1182021 01 20.
Artigo em Sueco | MEDLINE | ID: mdl-33474717

RESUMO

Continuous glucose monitoring (CGM) tracks glucose levels in real-time using a subcutaneous sensor, replacing intermittent blood sampling for self-monitoring of blood glucose (SMBG). CGM is a routine tool in type 1 diabetes management. In 2019, patients with type 2 diabetes were given the indication of CGM use by Swedish authorities; CGM can be considered when a patient despite multi-dose treatment with insulin does not achieve good glucose control and/or has problems with hypoglycaemia. Studies show that CGM provides improved glycaemic control compared to SMBG. The cost of CGM is higher than for SMBG and requires effort both by caregivers and patients. This should be gauged against the possible long-term health economic benefits of preventing diabetes complications.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Hipoglicemia , Glicemia , Automonitorização da Glicemia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/prevenção & controle
10.
Physiol Plant ; 172(1): 201-217, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33368469

RESUMO

Autumn senescence in aspen (Populus tremula) is precisely timed every year to relocate nutrients from leaves to storage organs before winter. Here we demonstrate how stem girdling, which leads to the accumulation of photosynthates in the crown, influences senescence. Girdling resulted in an early onset of senescence, but the chlorophyll degradation was slower and nitrogen more efficiently resorbed than during normal autumn senescence. Girdled stems accumulated or retained anthocyanins potentially providing photoprotection in senescing leaves. Girdling of one stem in a clonal stand sharing the same root stock did not affect senescence in the others, showing that the stems were autonomous in this respect. One girdled stem with unusually high chlorophyll and nitrogen contents maintained low carbon-to-nitrogen (C/N) ratio and did not show early senescence or depleted chlorophyll level unlike the other girdled stems suggesting that the responses depended on the genotype or its carbon and nitrogen status. Metabolite analysis highlighted that the tricarboxylic acid (TCA) cycle, salicylic acid pathway, and redox homeostasis are involved in the regulation of girdling-induced senescence. We propose that disrupted sink-source relation and C/N status can provide cues through the TCA cycle and phytohormone signaling to override the phenological control of autumn senescence in the girdled stems.


Assuntos
Clorofila , Populus , Fotossíntese , Folhas de Planta , Populus/genética , Estações do Ano
11.
Diabetologia ; 64(1): 95-108, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979073

RESUMO

AIMS/HYPOTHESIS: Non-Western immigrants to Europe are at high risk for type 2 diabetes. In this nationwide study including incident cases of type 2 diabetes, the aim was to compare all-cause mortality (ACM) and cause-specific mortality (CSM) rates in first- and second-generation immigrants with native Swedes. METHODS: People living in Sweden diagnosed with new-onset pharmacologically treated type 2 diabetes between 2006 and 2012 were identified through the Swedish Prescribed Drug Register. They were followed until 31 December 2016 for ACM and until 31 December 2012 for CSM. Analyses were adjusted for age at diagnosis, sex, socioeconomic status, education, treatment and region. Associations were assessed using Cox regression analysis. RESULTS: In total, 138,085 individuals were diagnosed with type 2 diabetes between 2006 and 2012 and fulfilled inclusion criteria. Of these, 102,163 (74.0%) were native Swedes, 28,819 (20.9%) were first-generation immigrants and 7103 (5.1%) were second-generation immigrants with either one or both parents born outside Sweden. First-generation immigrants had lower ACM rate (HR 0.80 [95% CI 0.76, 0.84]) compared with native Swedes. The mortality rates were particularly low in people born in non-Western regions (0.46 [0.42, 0.50]; the Middle East, 0.41 [0.36, 0.47]; Asia, 0.53 [0.43, 0.66]; Africa, 0.47 [0.38, 0.59]; and Latin America, 0.53 [0.42, 0.68]). ACM rates decreased with older age at migration and shorter stay in Sweden. Compared with native Swedes, first-generation immigrants with ≤ 24 years in Sweden (0.55 [0.51, 0.60]) displayed lower ACM rates than those spending >24 years in Sweden (0.92 [0.87, 0.97]). Second-generation immigrants did not have better survival rates than native Swedes but rather displayed higher ACM rates for people with both parents born abroad (1.28 [1.05, 1.56]). CONCLUSIONS/INTERPRETATION: In people with type 2 diabetes, the lower mortality rate in first-generation non-Western immigrants compared with native Swedes was reduced over time and was equalised in second-generation immigrants. These findings suggest that acculturation to Western culture may impact ACM and CSM in immigrants with type 2 diabetes but further investigation is needed. Graphical abstract.

12.
Nat Commun ; 11(1): 6388, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33319777

RESUMO

Evergreen conifers in boreal forests can survive extremely cold (freezing) temperatures during long dark winter and fully recover during summer. A phenomenon called "sustained quenching" putatively provides photoprotection and enables their survival, but its precise molecular and physiological mechanisms are not understood. To unveil them, here we have analyzed seasonal adjustment of the photosynthetic machinery of Scots pine (Pinus sylvestris) trees by monitoring multi-year changes in weather, chlorophyll fluorescence, chloroplast ultrastructure, and changes in pigment-protein composition. Analysis of Photosystem II and Photosystem I performance parameters indicate that highly dynamic structural and functional seasonal rearrangements of the photosynthetic apparatus occur. Although several mechanisms might contribute to 'sustained quenching' of winter/early spring pine needles, time-resolved fluorescence analysis shows that extreme down-regulation of photosystem II activity along with direct energy transfer from photosystem II to photosystem I play a major role. This mechanism is enabled by extensive thylakoid destacking allowing for the mixing of PSII with PSI complexes. These two linked phenomena play crucial roles in winter acclimation and protection.


Assuntos
Transferência de Energia , Fotossíntese/fisiologia , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Pinus sylvestris/metabolismo , Aclimatação , Clorofila , Cloroplastos/metabolismo , Cloroplastos/ultraestrutura , Fluorescência , Cinética , Luz , Processos Fotoquímicos , Complexo de Proteína do Fotossistema I/química , Complexo de Proteína do Fotossistema II/química , Estações do Ano , Temperatura , Tilacoides/metabolismo , Fatores de Tempo , Árvores/metabolismo
13.
Br J Gen Pract ; 70(701): e843-e851, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33139332

RESUMO

BACKGROUND: Colorectal cancer (CRC) diagnostics are challenging in primary care and reliable diagnostic aids are desired. Qualitative faecal immunochemical tests (FITs) have been used for suspected CRC in Sweden since the mid-2000s, but evidence regarding their effectiveness is scarce. Anaemia and thrombocytosis are both associated with CRC. AIM: To evaluate the usefulness of qualitative FITs requested for symptomatic patients in primary care, alone and combined with findings of anaemia and thrombocytosis, in the diagnosis of CRC. DESIGN AND SETTING: A population-based cohort study using electronic health records and data from the Swedish Cancer Register, covering five Swedish regions. METHOD: Patients aged ≥18 years in the five regions who had provided FITs requested by primary care practitioners from 1 January 2015 to 31 December 2015 were identified. FIT and blood-count data were registered and all CRC diagnoses made within 2 years were retrieved. Diagnostic measurements were calculated. RESULTS: In total, 15 789 patients provided FITs (four different brands); of these patients, 304 were later diagnosed with CRC. Haemoglobin levels were available for 13 863 patients, and platelet counts for 10 973 patients. Calculated for the different FIT brands only, the sensitivities for CRC were 81.6%-100%; specificities 65.7%-79.5%; positive predictive values 4.7%-8.1%; and negative predictive values 99.5%-100%. Calculated for the finding of either a positive FIT or anaemia, the sensitivities increased to 88.9-100%. Adding thrombocytosis did not further increase the diagnostic performance. CONCLUSION: Qualitative FITs requested in primary care seem to be useful as rule-in tests for referral when CRC is suspected. A negative FIT and no anaemia indicate a low risk of CRC.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Adolescente , Adulto , Estudos de Coortes , Neoplasias Colorretais/diagnóstico , Fezes/química , Hemoglobinas , Humanos , Sangue Oculto , Contagem de Plaquetas , Atenção Primária à Saúde , Sensibilidade e Especificidade , Suécia/epidemiologia
14.
Ecol Evol ; 10(21): 11922-11940, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33209260

RESUMO

Leaf shape is a defining feature of how we recognize and classify plant species. Although there is extensive variation in leaf shape within many species, few studies have disentangled the underlying genetic architecture. We characterized the genetic architecture of leaf shape variation in Eurasian aspen (Populus tremula L.) by performing genome-wide association study (GWAS) for physiognomy traits. To ascertain the roles of identified GWAS candidate genes within the leaf development transcriptional program, we generated RNA-Seq data that we used to perform gene co-expression network analyses from a developmental series, which is publicly available within the PlantGenIE resource. We additionally used existing gene expression measurements across the population to analyze GWAS candidate genes in the context of a population-wide co-expression network and to identify genes that were differentially expressed between groups of individuals with contrasting leaf shapes. These data were integrated with expression GWAS (eQTL) results to define a set of candidate genes associated with leaf shape variation. Our results identified no clear adaptive link to leaf shape variation and indicate that leaf shape traits are genetically complex, likely determined by numerous small-effect variations in gene expression. Genes associated with shape variation were peripheral within the population-wide co-expression network, were not highly connected within the leaf development co-expression network, and exhibited signatures of relaxed selection. As such, our results are consistent with the omnigenic model.

15.
Int J Colorectal Dis ; 35(11): 2035-2040, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32602056

RESUMO

BACKGROUND: Rectal bleeding is considered an alarm symptom for colorectal cancer (CRC) but it is common and mostly caused by benign conditions. Qualitative faecal immunochemical tests (FITs) for occult blood have been used as diagnostic aids for many years in Sweden when CRC is suspected. The study aimed to evaluate the usefulness of FITs requested by primary care physicians for patients with and without histories of rectal bleeding, in the diagnosis of CRC. METHODS: Results of all FITs requested in primary care for symptomatic patients in the Örebro region during 2015 were retrieved. Data on each patient's history of rectal bleeding was gathered from electronic health records. Patients diagnosed with CRC within 2 years were identified from the Swedish Cancer Register. The analysis focused on three-sample FITs, the customary FIT in Sweden. RESULTS: A total of 4232 patients provided three-sample FITs. Information about the presence/absence of rectal bleeding was available for 2027 patients, of which 59 were diagnosed with CRC. For 606 patients with the presence of rectal bleeding, the FIT showed sensitivity 96.2%, specificity 60.2%, positive predictive value 9.8% (95% CI 6.1-13.4) and negative predictive value 99.7% (95% CI 99.2-100) for CRC. For 1421 patients without rectal bleeding, the corresponding figures were 100%, 73.6%, 8.3% (95% CI 5.6-10.9) and 100% (95% CI 99.6-100). CONCLUSION: The diagnostic performance of a qualitative three-sample FIT provided by symptomatic patients in primary care was similar for those with and without a history of rectal bleeding. FITs seem useful for prioritising patients also with rectal bleeding for further investigation.


Assuntos
Neoplasias Colorretais , Sangue Oculto , Estudos de Coortes , Neoplasias Colorretais/complicações , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer , Fezes , Humanos , Imunoquímica , Atenção Primária à Saúde , Sensibilidade e Especificidade , Suécia/epidemiologia
16.
Diabetes Res Clin Pract ; 167: 108352, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32712123

RESUMO

AIMS: To examine if personnel resources and organisational features in Swedish primary health-care centres (PHCCs) are associated to all-cause mortality (ACM) in people with type 2 diabetes mellitus (T2DM). METHODS: A total of 187,570 people with T2DM registered in the Swedish National Diabetes Register (NDR) during 2013 were included in this nationwide cohort study. Individual NDR data were linked to data from a questionnaire addressing personnel resources and organisational features for 787 (68%) PHCCs as well as to individual data on socio-economic status and comorbidities. Furthermore, data on ACM were obtained and followed up until 30 January 2018. Hierarchical Cox regression analyses were applied. RESULTS: After a median follow-up of 4.2 years, 27,136 (14.5%) participants had died. An association was found between number of whole-time-equivalent (WTE) general practitioner's (GP's) devoted to diabetes care/500 people with T2DM and lower risk of early death (hazard ratio 0.919 [95% confidence interval 0.895-0.945] per additional WTE GP; p = 0.002). No other personnel resources or organisational features were significantly associated with ACM. CONCLUSIONS: This nationwide register-based cohort study suggests that the number of WTE GPs devoted to diabetes care have an impact on the risk of early death in people with T2DM.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Atenção Primária à Saúde/métodos , Idoso , Estudos de Coortes , Diabetes Mellitus Tipo 2/mortalidade , Feminino , Humanos , Estudos Longitudinais , Masculino , Taxa de Sobrevida
17.
Proc Natl Acad Sci U S A ; 117(30): 17499-17509, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32690715

RESUMO

Coping of evergreen conifers in boreal forests with freezing temperatures on bright winter days puts the photosynthetic machinery in great risk of oxidative damage. To survive harsh winter conditions, conifers have evolved a unique but poorly characterized photoprotection mechanism, a sustained form of nonphotochemical quenching (sustained NPQ). Here we focused on functional properties and underlying molecular mechanisms related to the development of sustained NPQ in Norway spruce (Picea abies). Data were collected during 4 consecutive years (2016 to 2019) from trees growing in sun and shade habitats. When day temperatures dropped below -4 °C, the specific N-terminally triply phosphorylated LHCB1 isoform (3p-LHCII) and phosphorylated PSBS (p-PSBS) could be detected in the thylakoid membrane. Development of sustained NPQ coincided with the highest level of 3p-LHCII and p-PSBS, occurring after prolonged coincidence of bright winter days and temperatures close to -10 °C. Artificial induction of both the sustained NPQ and recovery from naturally induced sustained NPQ provided information on differential dynamics and light-dependence of 3p-LHCII and p-PSBS accumulation as prerequisites for sustained NPQ. Data obtained collectively suggest three components related to sustained NPQ in spruce: 1) Freezing temperatures induce 3p-LHCII accumulation independently of light, which is suggested to initiate destacking of appressed thylakoid membranes due to increased electrostatic repulsion of adjacent membranes; 2) p-PSBS accumulation is both light- and temperature-dependent and closely linked to the initiation of sustained NPQ, which 3) in concert with PSII photoinhibition, is suggested to trigger sustained NPQ in spruce.


Assuntos
Fotossíntese , Picea/fisiologia , Estações do Ano , Proteínas das Membranas dos Tilacoides/metabolismo , Tilacoides/metabolismo , Sequência de Aminoácidos , Meio Ambiente , Complexos de Proteínas Captadores de Luz/metabolismo , Noruega , Fosforilação , Espectrometria de Massas em Tandem , Proteínas das Membranas dos Tilacoides/química , Árvores
18.
G3 (Bethesda) ; 10(1): 299-309, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31744900

RESUMO

The rate of meiotic recombination is one of the central factors determining genome-wide levels of linkage disequilibrium which has important consequences for the efficiency of natural selection and for the dissection of quantitative traits. Here we present a new, high-resolution linkage map for Populus tremula that we use to anchor approximately two thirds of the P. tremula draft genome assembly on to the expected 19 chromosomes, providing us with the first chromosome-scale assembly for P. tremula (Table 2). We then use this resource to estimate variation in recombination rates across the P. tremula genome and compare these results to recombination rates based on linkage disequilibrium in a large number of unrelated individuals. We also assess how variation in recombination rates is associated with a number of genomic features, such as gene density, repeat density and methylation levels. We find that recombination rates obtained from the two methods largely agree, although the LD-based method identifies a number of genomic regions with very high recombination rates that the map-based method fails to detect. Linkage map and LD-based estimates of recombination rates are positively correlated and show similar correlations with other genomic features, showing that both methods can accurately infer recombination rate variation across the genome. Recombination rates are positively correlated with gene density and negatively correlated with repeat density and methylation levels, suggesting that recombination is largely directed toward gene regions in P. tremula.


Assuntos
Variação Genética , Populus/genética , Recombinação Genética , Cromossomos de Plantas/genética , Metilação de DNA , Desequilíbrio de Ligação
19.
BMC Pregnancy Childbirth ; 19(1): 398, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675922

RESUMO

BACKGROUND: The optimal criteria to diagnose gestational diabetes mellitus (GDM) remain contested. The Swedish National Board of Health introduced the 2013 WHO criteria in 2015 as a recommendation for initiation of treatment for hyperglycaemia during pregnancy. With variation in GDM screening and diagnostic practice across the country, it was agreed that the shift to new guidelines should be in a scientific and structured way. The aim of the Changing Diagnostic Criteria for Gestational Diabetes (CDC4G) in Sweden ( www.cdc4g.se/en ) is to evaluate the clinical and health economic impacts of changing diagnostic criteria for GDM in Sweden and to create a prospective cohort to compare the many long-term outcomes in mother and baby under the old and new diagnostic approaches. METHODS: This is a stepped wedge cluster randomised controlled trial, comparing pregnancy outcomes before and after the switch in GDM criteria across 11 centres in a randomised manner. The trial includes all pregnant women screened for GDM across the participating centres during January-December 2018, approximately two thirds of all pregnancies in Sweden in a year. Women with pre-existing diabetes will be excluded. Data will be collected through the national Swedish Pregnancy register and for follow up studies other health registers will be included. DISCUSSION: The stepped wedge RCT was chosen to be the best study design for evaluating the shift from old to new diagnostic criteria of GDM in Sweden. The national quality registers provide data on the whole pregnant population and gives a possibility for follow up studies of both mother and child. The health economic analysis from the study will give a solid evidence base for future changes in order to improve immediate pregnancy, as well as long term, outcomes for mother and child. TRIAL REGISTRATION: CDC4G is listed on the ISRCTN registry with study ID ISRCTN41918550 (15/12/2017).


Assuntos
Diabetes Gestacional/diagnóstico , Guias de Prática Clínica como Assunto , Diagnóstico Pré-Natal/normas , Adulto , Análise por Conglomerados , Feminino , Humanos , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Suécia
20.
Lakartidningen ; 1162019 Feb 19.
Artigo em Sueco | MEDLINE | ID: mdl-31192390

RESUMO

Bariatric surgery is a well-documented and good alternative for treatment of obesity with and without type 2-diabetes. One of the documented complications is postprandial hypoglycemia, with possibly serious consequences. We present such a case, what is known of underlying mechanisms, and treatment options.


Assuntos
Derivação Gástrica/efeitos adversos , Hipoglicemia/etiologia , Feminino , Humanos , Hipoglicemia/dietoterapia , Hipoglicemia/fisiopatologia , Pessoa de Meia-Idade , Obesidade/cirurgia , Complicações Pós-Operatórias/dietoterapia , Complicações Pós-Operatórias/fisiopatologia
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