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1.
Ann Bot ; 124(4): 645-652, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-30715120

RESUMO

BACKGROUND AND AIMS: Jatropha curcas (jatropha) is an oil crop cultivated in (sub)tropical regions around the world, and holds great promise as a renewable energy source. However, efforts to fully commercialize jatropha are currently hampered by the lack of genetic diversity in the extant breeding germplasm, and by the toxicity of its seeds meaning that its seed cake cannot be used as a protein source in animal feed, among other constraints. In Mexico, the species' native range, there are jatropha plants whose seeds are used to prepare traditional meals. This non-toxic jatropha 'type' is considered to harbour low genetic variation due to a presumed domestication bottleneck and therefore to be of limited breeding value; yet, very little is known regarding its origin and genetic diversity. METHODS: Using genotyping-by-sequencing (GBS), we extensively genotyped both indigenous toxic and non-toxic jatropha collected along roads and home gardens throughout southern Mexico. KEY RESULTS: Single nucleotide polymorphism diversity in non-toxic jatropha is relatively high, particularly in northern Veracruz state, the probable origin of this germplasm. Genetic differences between toxic and non-toxic indigenous genotypes are overall quite small. A a genome-wide association study supported a genomic region (on LG 8, scaffold NW_012130064), probably involved in the suppression of seed toxicity. CONCLUSIONS: Conservation actions are urgently needed to preserve this non-toxic indigenous, relatively wild germplasm, having potential as a fuel feedstock, animal feed and food source among other uses. More generally, this work demonstrates the value of conservation genomic research on the indigenous gene pool of economically important plant species.


Assuntos
Jatropha , Biocombustíveis , Estudo de Associação Genômica Ampla , México , Polimorfismo de Nucleotídeo Único , Sementes
2.
Am J Transplant ; 17(1): 28-41, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27862883

RESUMO

The XIII Banff meeting, held in conjunction the Canadian Society of Transplantation in Vancouver, Canada, reviewed the clinical impact of updates of C4d-negative antibody-mediated rejection (ABMR) from the 2013 meeting, reports from active Banff Working Groups, the relationships of donor-specific antibody tests (anti-HLA and non-HLA) with transplant histopathology, and questions of molecular transplant diagnostics. The use of transcriptome gene sets, their resultant diagnostic classifiers, or common key genes to supplement the diagnosis and classification of rejection requires further consensus agreement and validation in biopsies. Newly introduced concepts include the i-IFTA score, comprising inflammation within areas of fibrosis and atrophy and acceptance of transplant arteriolopathy within the descriptions of chronic active T cell-mediated rejection (TCMR) or chronic ABMR. The pattern of mixed TCMR and ABMR was increasingly recognized. This report also includes improved definitions of TCMR and ABMR in pancreas transplants with specification of vascular lesions and prospects for defining a vascularized composite allograft rejection classification. The goal of the Banff process is ongoing integration of advances in histologic, serologic, and molecular diagnostic techniques to produce a consensus-based reporting system that offers precise composite scores, accurate routine diagnostics, and applicability to next-generation clinical trials.


Assuntos
Arterite/imunologia , Complemento C4b/imunologia , Rejeição de Enxerto/classificação , Rejeição de Enxerto/patologia , Isoanticorpos/imunologia , Transplante de Rim/efeitos adversos , Fragmentos de Peptídeos/imunologia , Rejeição de Enxerto/etiologia , Humanos , Relatório de Pesquisa
3.
J Evol Biol ; 29(2): 253-64, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26484499

RESUMO

Both traits and the plasticity of these traits are subject to evolutionary change and therefore affect the long-term persistence of populations and their role in local communities. We subjected clones from 12 different populations of Alnus glutinosa, located along a latitudinal gradient, to two different temperature treatments, to disentangle the distribution of genetic variation in timing of bud burst and bud burst plasticity within and among genotypes, populations, and regions. We calculated heritability and evolvability estimates for bud burst and bud burst plasticity and assessed the influence of divergent selection relative to neutral drift. We observed higher levels of heritability and evolvability for bud burst than for its plasticity, whereas the total phenological heritability and evolvability (i.e. combining timing of bud burst and bud burst plasticity) suggest substantial evolutionary potential with respect to phenology. Earlier bud burst was observed for the low-latitudinal populations than for the populations from higher latitudes, whereas the high-latitudinal populations did not show the expected delayed bud burst. This countergradient variation can be due to evolution towards increased phenological plasticity at higher latitudes. However, because we found little evidence for adaptive differences in phenological plasticity across the latitudinal gradient, we suggest differential frost tolerance as the most likely explanation for the observed phenological patterns in A. glutinosa.


Assuntos
Alnus/classificação , Alnus/fisiologia , Evolução Biológica , Fenótipo , Alnus/genética , Temperatura Baixa , Genótipo , Modelos Biológicos , Polimorfismo de Nucleotídeo Único/genética
4.
Heredity (Edinb) ; 115(5): 415-25, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25944466

RESUMO

The evaluation of the molecular signatures of selection in species lacking an available closely related reference genome remains challenging, yet it may provide valuable fundamental insights into the capacity of populations to respond to environmental cues. We screened 25 native populations of the tree species Frangula alnus subsp. alnus (Rhamnaceae), covering three different geographical scales, for 183 annotated single-nucleotide polymorphisms (SNPs). Standard population genomic outlier screens were combined with individual-based and multivariate landscape genomic approaches to examine the strength of selection relative to neutral processes in shaping genomic variation, and to identify the main environmental agents driving selection. Our results demonstrate a more distinct signature of selection with increasing geographical distance, as indicated by the proportion of SNPs (i) showing exceptional patterns of genetic diversity and differentiation (outliers) and (ii) associated with climate. Both temperature and precipitation have an important role as selective agents in shaping adaptive genomic differentiation in F. alnus subsp. alnus, although their relative importance differed among spatial scales. At the 'intermediate' and 'regional' scales, where limited genetic clustering and high population diversity were observed, some indications of natural selection may suggest a major role for gene flow in safeguarding adaptability. High genetic diversity at loci under selection in particular, indicated considerable adaptive potential, which may nevertheless be compromised by the combined effects of climate change and habitat fragmentation.


Assuntos
Genética Populacional , Rhamnus/genética , Seleção Genética , Adaptação Biológica/genética , Animais , Teorema de Bayes , Clima , Europa (Continente) , Variação Genética , Genoma de Planta , Genômica , Genótipo , Geografia , Insetos , Polinização , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Árvores/genética
5.
Am J Transplant ; 14(4): 936-42, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24712331

RESUMO

Early pancreas graft loss is usually attributed to technical failure while the possibility of antibody-mediated rejection (AMR) is generally overlooked. To investigate the role of AMR in early pancreas graft loss, we retrospectively assessed 256 patients with simultaneous pancreas-kidney transplantation (SPK) between 1985 and 2010 at our institute. We included 33 SPK patients who lost their pancreas graft <1 year after transplantation. AMR was diagnosed based on donor-specific antibodies, C4d and histology in 7 cases, 8 cases were suspicious for AMR and 18 pancreas graft losses were not due to AMR. Acute AMR occurred >1 month after transplantation in 6/7 cases, whereas all other causes typically led to loss <1 month after transplantation. Thrombotic lesions occurred equally among the 33 cases. In 12/18 concurrent kidney specimens, the diagnostic results paralleled those of the pancreas graft. All patients with acute AMR of the pancreas graft lost their renal grafts <1 year after transplantation. In the setting of a thrombotic event, histopathological analysis of early pancreas graft loss is advisable to rule out the possibility of AMR, particularly because a diagnosis of acute AMR has important consequences for renal graft outcomes.


Assuntos
Rejeição de Enxerto/diagnóstico , Isoanticorpos/sangue , Transplante de Rim/efeitos adversos , Transplante de Pâncreas/efeitos adversos , Pancreatopatias/complicações , Complicações Pós-Operatórias/diagnóstico , Trombose/fisiopatologia , Adulto , Aloenxertos , Estudos de Casos e Controles , Complemento C4b/imunologia , Feminino , Seguimentos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/mortalidade , Humanos , Imunidade Celular/imunologia , Isoanticorpos/imunologia , Masculino , Pessoa de Meia-Idade , Pancreatopatias/cirurgia , Fragmentos de Peptídeos/imunologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Doadores de Tecidos
6.
Am J Transplant ; 13(2): 485-92, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23167441

RESUMO

In renal transplant patients with de novo donor-specific antibodies (dnDSA) we studied the value of microcirculation inflammation (MI; defined by the addition of glomerulitis (g) and peritubular capillaritis (ptc) scores) to assess long-term graft survival in a retrospective cohort study. Out of all transplant patients with standard immunological risk (n = 638), 79 (12.4%) developed dnDSA and 58/79 (73%) had an indication biopsy at or after dnDSA development. Based on the MI score on that indication biopsy patients were categorized, MI0 (n = 26), MI1 + 2 (n = 21) and MI ≥ 3 (n = 11). The MI groups did not differ significantly pretransplantation, whereas posttransplantation higher MI scores developed more anti-HLA class I + II DSA (p = 0.011), showed more TCMR (p < 0.001) and showed a trend to C4d-positive staining (p = 0.059). Four-year graft survival estimates from time of indication biopsy were MI0 96.1%, MI1 + 2 76.1% and MI ≥ 3 17.1%; resulting in a 24-fold increased risk of graft failure in the MI ≥ 3 compared to the MI0 group (p = 0.003; 95% CI [3.0-196.0]). When adjusted for C4d, MI ≥ 3 still had a 21-fold increased risk of graft failure (p = 0.005; 95% CI [2.5-180.0]), while C4d positivity on indication biopsy lost significance. In renal transplant patients with de novo DSA, microcirculation inflammation, defined by g + ptc, associates with graft survival.


Assuntos
Anticorpos/imunologia , Transplante de Rim/imunologia , Transplante de Rim/métodos , Rim/imunologia , Insuficiência Renal/terapia , Adulto , Biópsia , Complemento C4b/análise , Feminino , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Inflamação , Masculino , Microcirculação , Pessoa de Meia-Idade , Modelos Estatísticos , Fragmentos de Peptídeos/análise , Estudos Retrospectivos , Fatores de Risco , Doadores de Tecidos
7.
Nat Commun ; 12(1): 516, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483517

RESUMO

Understanding how biological and environmental factors interactively shape the global distribution of plant and animal genetic diversity is fundamental to biodiversity conservation. Genetic diversity measured in local populations (GDP) is correspondingly assumed representative for population fitness and eco-evolutionary dynamics. For 8356 populations across the globe, we report that plants systematically display much lower GDP than animals, and that life history traits shape GDP patterns both directly (animal longevity and size), and indirectly by mediating core-periphery patterns (animal fecundity and plant dispersal). Particularly in some plant groups, peripheral populations can sustain similar GDP as core populations, emphasizing their potential conservation value. We further find surprisingly weak support for general latitudinal GDP trends. Finally, contemporary rather than past climate contributes to the spatial distribution of GDP, suggesting that contemporary environmental changes affect global patterns of GDP. Our findings generate new perspectives for the conservation of genetic resources at worldwide and taxonomic-wide scales.


Assuntos
Biodiversidade , Clima , Ecossistema , Variação Genética , Plantas/genética , Algoritmos , Distribuição Animal , Animais , Evolução Molecular , Genética Populacional , Geografia , Características de História de Vida , Modelos Teóricos , Filogenia , Dispersão Vegetal , Plantas/classificação
8.
Am J Transplant ; 10(7): 1660-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20455878

RESUMO

C4d+ antibody-mediated rejection following pancreas transplantation has not been well characterized. Therefore, we assessed the outcomes of 27 pancreas transplantation patients (28 biopsies), with both C4d staining and donor-specific antibodies (DSA) determined, from a cohort of 257 patients. The median follow-up was 50 (interquartile range [IQR] 8-118) months. Patients were categorized into 3 groups: group 1, patients with minimal or no C4d staining and no DSA (n = 13); group 2, patients with either DSA present but no C4d, diffuse C4d+ and no DSA or focal C4d+ and DSA (n = 6); group 3, patients with diffuse C4d+ staining and DSA (n = 9). Active septal inflammation, acinar inflammation and acinar cell injury/necrosis were significantly more abundant in group 3 than in group 2 (respective p-values: 0.009; 0.033; 0.025) and in group 1 (respective p-values: 0.034; 0.009; 0.002). The overall uncensored pancreas graft survival rate for groups 1, 2 and 3 were 53.3%, 66.7% and 34.6%, respectively (p = 0.044). In conclusion, recipients of pancreas transplants with no C4d or DSA had excellent long-term graft survival in comparison with patients with both C4d+ and DSA present. Hence, C4d should be used as an additional marker in combination with DSA in the evaluation of pancreas transplant biopsies.


Assuntos
Complemento C4b/análise , Rejeição de Enxerto/patologia , Transplante de Pâncreas/patologia , Fragmentos de Peptídeos/análise , Adulto , Biópsia , Corantes , Registros Eletrônicos de Saúde , Feminino , Seguimentos , Rejeição de Enxerto/sangue , Rejeição de Enxerto/imunologia , Antígenos HLA/análise , Teste de Histocompatibilidade , Humanos , Imunossupressores/uso terapêutico , Inflamação/etiologia , Inflamação/patologia , Masculino , Pessoa de Meia-Idade , Transplante de Pâncreas/imunologia , Complicações Pós-Operatórias/imunologia , Complicações Pós-Operatórias/patologia , Fatores de Tempo , Transplante Homólogo/patologia , Resultado do Tratamento
9.
J Thromb Haemost ; 7(2): 347-54, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18983488

RESUMO

BACKGROUND: High-density lipoprotein (HDL) exerts a variety of anti-atherothrombotic functions, including a potent anti-inflammatory impact. In line, the direct pro-inflammatory effects of C-reactive protein (CRP) can be attenuated by HDL in vitro. OBJECTIVE: To evaluate whether this also holds true in humans, we assessed the ability of reconstituted HDL to neutralize CRP-mediated activation of coagulation and inflammation. METHODS: Fifteen healthy male volunteers received an infusion of recombinant human (rh)CRP (1.25 mg kg(-1) body weight). In eight of these volunteers, an infusion of human apoAI reconstituted with phosphatidylcholine (apoAI-PC; 80 mg kg(-1) body weight) preceded rhCRP infusion. RESULTS: Infusion of rhCRP alone elicited an inflammatory response and thrombin generation. In individuals who received apoAI-PC prior to rhCRP, these effects were abolished. Parallel tests in primary human endothelial cells showed that apoAI-PC preincubation with rhCRP abolished the CRP-mediated activation of inflammation as assessed by IL-6 release. Although we were able to show that rhCRP co-eluted with HDL after size-exclusion chromatography, plasmon surface resonance indicated the absence of a direct interaction between HDL and CRP. CONCLUSION: Infusion of apoAI-PC prior to rhCRP in humans completely prevents the direct atherothrombotic effects of rhCRP. These findings imply that administration of apoAI-PC may offer benefit in patients with increased CRP.


Assuntos
Apolipoproteína A-I/farmacologia , Proteína C-Reativa/farmacologia , Inflamação/prevenção & controle , Trombose/etiologia , Adulto , Apolipoproteína A-I/administração & dosagem , Aterosclerose , Proteína C-Reativa/administração & dosagem , Células Endoteliais , Humanos , Inflamação/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Fosfatidilcolinas/administração & dosagem , Proteínas Recombinantes
10.
Scand J Gastroenterol ; 35(1): 70-6, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10672838

RESUMO

BACKGROUND: Our objective was to evaluate the diagnostic accuracy of abdominal symptoms in gallstones in studies using ultrasonography or oral cholecystography as the reference standard and to assess the extent to which variability in diagnostic accuracy is explained by patient selection and other characteristics of study design. METHODS: A Medline search (1966-1998) was conducted in combination with reference checking for further relevant publications. Two independent assessors selected controlled studies that included patients > or =18 years of age. Articles were excluded if sensitivity and specificity could not be extracted or the included patients were at extraordinary risk for gallstones. Seven abdominal symptoms were evaluated. Modification of the diagnostic accuracy by clinical setting, extent of the disease, blinding, age, and sex was analysed by using logistic regression. RESULTS: A total of 24 publications were included. The symptoms 'biliary colic', 'radiating pain', and 'analgesics used' were consistently related to gallstones. The setting of the study had a significant effect on the diagnostic accuracy of these symptoms. The unadjusted, pooled diagnostic odds ratios, however, were low (2.6 (95% confidence interval, 2.4-2.9), 2.8 (2.2-3.7), and 2 (1.6-2.5), respectively). The diagnostic odds ratio of biliary colic increased with the extent of gallstone disease (13.3 (4.2-42). CONCLUSIONS: Although biliary colic was specific for gallstones, 80% of the referred patients with gallstones presented with other abdominal symptoms. There is no current evidence that justifies the use of single abdominal symptoms, other than biliary colic, in the diagnosis of symptomatic gallstones. Further research should focus on the prognosis of patients with non-specific abdominal symptoms and gallstones.


Assuntos
Dor Abdominal/etiologia , Colelitíase/diagnóstico , Analgésicos/uso terapêutico , Colelitíase/complicações , Cólica/etiologia , Alimentos/efeitos adversos , Humanos , Razão de Chances , Sensibilidade e Especificidade
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