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1.
Plant Genome ; 16(4): e20401, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37903749

RESUMO

Discovery and analysis of genetic variants underlying agriculturally important traits are key to molecular breeding of crops. Reduced representation approaches have provided cost-efficient genotyping using next-generation sequencing. However, accurate genotype calling from next-generation sequencing data is challenging, particularly in polyploid species due to their genome complexity. Recently developed Bayesian statistical methods implemented in available software packages, polyRAD, EBG, and updog, incorporate error rates and population parameters to accurately estimate allelic dosage across any ploidy. We used empirical and simulated data to evaluate the three Bayesian algorithms and demonstrated their impact on the power of genome-wide association study (GWAS) analysis and the accuracy of genomic prediction. We further incorporated uncertainty in allelic dosage estimation by testing continuous genotype calls and comparing their performance to discrete genotypes in GWAS and genomic prediction. We tested the genotype-calling methods using data from two autotetraploid species, Miscanthus sacchariflorus and Vaccinium corymbosum, and performed GWAS and genomic prediction. In the empirical study, the tested Bayesian genotype-calling algorithms differed in their downstream effects on GWAS and genomic prediction, with some showing advantages over others. Through subsequent simulation studies, we observed that at low read depth, polyRAD was advantageous in its effect on GWAS power and limit of false positives. Additionally, we found that continuous genotypes increased the accuracy of genomic prediction, by reducing genotyping error, particularly at low sequencing depth. Our results indicate that by using the Bayesian algorithm implemented in polyRAD and continuous genotypes, we can accurately and cost-efficiently implement GWAS and genomic prediction in polyploid crops.


Assuntos
Estudo de Associação Genômica Ampla , Genômica , Estudo de Associação Genômica Ampla/métodos , Teorema de Bayes , Genótipo , Genômica/métodos , Poliploidia
2.
Behav Sci Law ; 41(2-3): 124-140, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37134138

RESUMO

Although mental illness has a demonstrated link with violence, the prevalence of targeted (planned and goal-directed) violence perpetrated by individuals with mental illness and its association with psychiatric symptoms is relatively unexplored. File information was compared for all 293 individuals found not criminally responsible due to mental illness in British Columbia between 2001 and 2005, of whom 19% had committed targeted violence. Most individuals with targeted offenses displayed at least one warning behavior before their offense (93%); all displayed delusions and approximately one third exhibited hallucinations. Compared to individuals who perpetrated non-targeted offenses, the individuals with targeted offenses displayed greater proportions of threats/criminal harassment, had female victims, displayed a psychotic disorder and/or personality disorder, and displayed delusions during the offense. This implies that severe psychiatric disorders do not preclude the perpetration of planned violence and suggests that exploring symptoms of mental illness that may be proximally indicative of targeted violence is important in preventing future acts.


Assuntos
Transtornos Mentais , Transtornos Psicóticos , Humanos , Feminino , Prevalência , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Violência/psicologia , Transtornos da Personalidade
4.
Front Pediatr ; 10: 870497, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120656

RESUMO

Neonatal AKI (NAKI) remains a challenge in low- and middle-income countries (LMICs). In this perspective, we address issues of diagnosis and risk factors particular to less well-resourced regions. The conservative management pre-kidney replacement therapy (pre-KRT) is prioritized and challenges of KRT are described with improvised dialysis techniques also included. Special emphasis is placed on ethical and palliation principles.

5.
Pediatr Infect Dis J ; 40(9): e323-e332, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34397776

RESUMO

BACKGROUND: Globally, very few childhood deaths have been attributed to coronavirus disease 2019 (COVID-19). We evaluated clinical, microbiologic and postmortem histopathologic findings in childhood deaths in whom severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified antemortem or postmortem. METHODS: Surveillance of childhood deaths was ongoing during the initial COVID-19 outbreak in South Africa from April 14, 2020, to August 31, 2020. All children hospitalized during this time had a SARS-CoV-2 test done as part of standard of care. Postmortem sampling included minimally invasive tissue sampling (MITS) of lung, liver and heart tissue; blood and lung samples for bacterial culture and molecular detection of viruses (including SARS-CoV-2) and bacteria. The cause of death attribution was undertaken by a multidisciplinary team and reported using World Health Organization framework for cause of death attribution. RESULTS: SARS-CoV-2 was identified on antemortem and/or postmortem sampling in 11.7% (20/171) of deceased children, including 13.2% (12/91) in whom MITS was done. Eighteen (90%) of 20 deaths with SARS-CoV-2 infection were <12 months age. COVID-19 was attributed in the causal pathway to death in 91.7% (11/12) and 87.5% (7/8) cases with and without MITS, respectively. Lung histopathologic features in COVID-19-related deaths included diffuse alveolar damage (n = 6, 54.5%), type 2 pneumocyte proliferation (n = 6, 54.5%) and hyaline membrane formation (n = 5, 36.4%). Culture-confirmed invasive bacterial disease was evident in 54.5% (6/11) of COVID-19 attributed deaths investigated with MITS. CONCLUSIONS: COVID-19 was in the causal pathway of 10.5% (18/171) of all childhood deaths under surveillance. The postmortem histopathologic features in fatal COVID-19 cases in children were consistent with reports on COVID-19 deaths in adults; although there was a high prevalence of invasive bacterial disease in the children.


Assuntos
COVID-19/mortalidade , SARS-CoV-2/isolamento & purificação , Adolescente , COVID-19/complicações , COVID-19/patologia , COVID-19/terapia , Criança , Pré-Escolar , Feminino , Gastroenterite/complicações , Humanos , Lactente , Recém-Nascido , Masculino , Respiração Artificial , Doenças Respiratórias/complicações , Convulsões/complicações , África do Sul/epidemiologia
6.
Bone Rep ; 14: 100751, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33644265

RESUMO

INTRODUCTION: We hypothesized that the prevalence of vertebral fractures would be low and that bone mineral density (BMD) would be less severely affected in a black South African (SA) population treated with glucocorticoids (GCs) than that reported in mainly white populations. METHODS: All children aged 5-17.9 years with chronic non-malignant illnesses who were on GCs (intravenous or oral) for greater than 3 months duration were evaluated. DXA scans were performed using a Hologic Discovery machine (Software version Apex 4.0.2) and the Hologic paediatric reference database. Whole body less head (WBLH) and lumbar spine (LS) bone mineral content (BMC) and density (BMD) Z-scores unadjusted and adjusted for height were calculated using the Zemel equation calculator. RESULTS: Seventy-two patients (49% with renal, 24% with rheumatic, 14% with neurological, 11% with hepatic and 3% with respiratory conditions; mean age 11.6 ± 3.3 years, 57% boys, 92% SA black) were enrolled. The mean duration of GC treatment was 34.1 (±25.1) months. Mean WBLH and LS height adjusted BMD Z-scores were -1.2 ± 1.5 and -0.9 ± 1.0 respectively. Eleven percent of patients had a LS height adjusted BMD Z-score ≤ -2. The prevalence of vertebral fractures on lateral vertebral fracture assessment (VFA) was 15% (11 of 72 patients). CONCLUSION: The prevalence of vertebral fractures (15%) in predominantly black children on GCs with chronic non-malignant illnesses is similar to that reported from North America suggesting that routine yearly DXA scans including VFA are warranted in this highly at-risk population.

7.
SA J Radiol ; 24(1): 1820, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670630

RESUMO

BACKGROUND: The role of the voiding cystourethrogram (VCUG) in the follow-up of children with posterior urethral valves (PUVs) post-ablation has been considered a standard practice. The urethral ratio and gradient of change have proven to be useful. OBJECTIVES: We aimed to review the role of the 'ideal' ratio on predicting residual PUV post-ablation. METHODS: A systematic review of the PubMed, SCOPUS and Web of Science databases was performed (April 2019). The search terms included 'Urethral Ratio and Posterior urethral valve ablation'. All cited reference lists were further evaluated for additional inclusive studies. RESULTS: Eleven studies were identified, of which nine were relevant to the topic. Case reports, comments and adult and animal studies were excluded, leaving four studies for critical review. In total, 338 patients were assessed. The control group consisted of 167 age-matched, male children. Study regions included India and Australia. The ages ranged from 15 days to 3.4 years. Ablation methods included the use of a resectoscope with cutting diathermy, cold knife or Bugbee electrode. The mean urethral ratios in the control group ranged from 1.04 to 1.73. The suggested predictive urethral cut-off ratios recommended include 2.2 (p = 0.001), 2.5-3 and 3.5. CONCLUSION: Although the precise cut-off ratio could not be clearly defined in this review, a urethral ratio less than a range of 2.2-3.5 has proven to be a beneficial predictor of ablation success and should thus be incorporated into standard VCUG reporting templates in the follow-up of PUVs in male children in resource-limited settings.

8.
Clin Infect Dis ; 69(Suppl 4): S361-S373, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31598659

RESUMO

BACKGROUND: Current estimates for causes of childhood deaths are mainly premised on modeling of vital registration and limited verbal autopsy data and generally only characterize the underlying cause of death (CoD). We investigated the potential of minimally invasive tissue sampling (MITS) for ascertaining the underlying and immediate CoD in children 1 month to 14 years of age. METHODS: MITS included postmortem tissue biopsies of brain, liver, and lung for histopathology examination; microbial culture of blood, cerebrospinal fluid (CSF), liver, and lung samples; and molecular microbial testing on blood, CSF, lung, and rectal swabs. Each case was individually adjudicated for underlying, antecedent, and immediate CoD by an international multidisciplinary team of medical experts and coded using the International Classification of Diseases, Tenth Revision (ICD-10). RESULTS: An underlying CoD was determined for 99% of 127 cases, leading causes being congenital malformations (18.9%), complications of prematurity (14.2%), human immunodeficiency virus/AIDS (12.6%), diarrheal disease (8.7%), acute respiratory infections (7.9%), injuries (7.9%), and malignancies (7.1%). The main immediate CoD was pneumonia, sepsis, and diarrhea in 33.9%, 19.7%, and 10.2% of cases, respectively. Infection-related deaths were either an underlying or immediate CoD in 78.0% of cases. Community-acquired pneumonia deaths (n = 32) were attributed to respiratory syncytial virus (21.9%), Pneumocystis jirovecii (18.8%), cytomegalovirus (15.6%), Klebsiella pneumoniae (15.6%), and Streptococcus pneumoniae (12.5%). Seventy-one percent of 24 sepsis deaths were hospital-acquired, mainly due to Acinetobacter baumannii (47.1%) and K. pneumoniae (35.3%). Sixty-two percent of cases were malnourished. CONCLUSIONS: MITS, coupled with antemortem clinical information, provides detailed insight into causes of childhood deaths that could be informative for prioritization of strategies aimed at reducing under-5 mortality.


Assuntos
Manejo de Espécimes/métodos , Adolescente , Autopsia/métodos , Causas de Morte , Criança , Pré-Escolar , Diagnóstico , Estudos Epidemiológicos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Projetos Piloto , Estudos Prospectivos , África do Sul
9.
Ann Bot ; 124(4): 731-748, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-30247525

RESUMO

BACKGROUND AND AIMS: Miscanthus, a C4 perennial grass native to East Asia, is a promising biomass crop. Miscanthus sacchariflorus has a broad geographic range, is used to produce paper in China and is one of the parents (along with Miscanthus sinensis) of the important biomass species Miscanthus × giganteus. The largest study of M. sacchariflorus population genetics to date is reported here. METHODS: Collections included 764 individuals across East Asia. Samples were genotyped with 34 605 single nucleotide polymorphisms (SNPs) derived from restriction site-associated DNA sequencing (RAD-seq) and ten plastid microsatellites, and were subjected to ploidy analysis by flow cytometry. KEY RESULTS: Six major genetic groups within M. sacchariflorus were identified using SNP data: three diploid groups, comprising Yangtze (M. sacchariflorus ssp. lutarioriparius), N China and Korea/NE China/Russia; and three tetraploid groups, comprising N China/Korea/Russia, S Japan and N Japan. Miscanthus sacchariflorus ssp. lutarioriparius was derived from the N China group, with a substantial bottleneck. Japanese and mainland tetraploids originated from independent polyploidization events. Hybrids between diploid M. sacchariflorus and M. sinensis were identified in Korea, but without introgression into either parent species. In contrast, tetraploid M. sacchariflorus in southern Japan and Korea exhibited substantial hybridization and introgression with local diploid M. sinensis. CONCLUSIONS: Genetic data indicated that the land now under the Yellow Sea was a centre of diversity for M. sacchariflorus during the last glacial maximum, followed by a series of migrations as the climate became warmer and wetter. Overall, M. sacchariflorus has greater genetic diversity than M. sinensis, suggesting that breeding and selection within M. sacchariflorus will be important for the development of improved M. × giganteus. Ornamental M. sacchariflorus genotypes in Europe and North America represent a very narrow portion of the species' genetic diversity, and thus do not well represent the species as a whole.


Assuntos
Diploide , Tetraploidia , China , Europa (Continente) , Ásia Oriental , Humanos , Japão , América do Norte , Poaceae
10.
Physiol Plant ; 167(1): 111-126, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30421426

RESUMO

As a consequence of global climate change, cold acclimation and deacclimation cycles are becoming increasingly frequent during winter in temperate regions. However, little is known about plant deacclimation and in particular reacclimation mechanisms, although deacclimation resistance and the ability to reacclimate may have wide-ranging consequences regarding plant productivity in a changing climate. Here, we report time-dependent responses of freezing tolerance, respiration rates, metabolite contents (high-resolution magic angle spinning NMR) and fatty acid levels (gas chromatography) in flower buds of two ecodormant Ribes nigrum cultivars exposed to three different deacclimation temperatures followed by a reacclimation treatment at 4°C. The data reveal that despite differences in the progression of deacclimation, the capacity of blackcurrant flower buds to reharden in late winter is virtually non-existing, implying that increasingly irregular temperature patterns is critical for blackcurrant fruit yield. The early phase of deacclimation is associated with a transient increase in respiration and decreasing contents of amino acids, tricarboxylic acid (TCA) cycle intermediates and sugars, indicating an increased need for carbon sources and respiratory energy production for the activation of growth. Decreasing sugar levels may additionally cause loss of freezing tolerance. Deacclimation also involves desaturation of membrane lipids, which likely also contributes to decreased freezing tolerance but may also reflect biosynthesis of signaling molecules stimulating growth and floral organ differentiation. These data provide new insights into the under-researched deacclimation mechanisms and the ability of blackcurrant to reacclimate following different advancements of deacclimation and contribute to our understanding of plant responses to increasingly irregular temperature patterns.


Assuntos
Ribes/metabolismo , Aclimatação/fisiologia , Ciclo do Ácido Cítrico/fisiologia , Mudança Climática , Temperatura
11.
Water Res ; 144: 183-191, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30029077

RESUMO

Seawater reverse osmosis (SWRO) is becoming an increasingly important source of potable water in arid and semi-arid regions worldwide. Discharge of brine-effluent from desalination facilities has been shown to significantly impact coastal marine ecosystems ranging from seagrass meadows to microbial communities. In this study, we examined the impacts of increased salinity (10% above ambient) and presence of antiscalants (0.2 mg L-1, polyphosphonate-based) on three reef-building coral species; Stylophora pistillata, Acropora tenuis and Pocillopora verrucosa, from the Gulf of Aqaba (northern Red-Sea). Our results indicate that the corals, as well as associated bacteria and algae, were significantly impaired by the elevated salinity and antiscalants, leading to partial bleaching. Specifically, the abundance of bacteria and symbiotic algae as well as calcification rates were typically lower (20-85%, 50-90% and 40-50%, respectively) following incubations with both amendments. However, the impact of desalination brine was often species-specific. Thus, we propose that the ecotoxicological criteria used for hard corals should be determined based on the sensitivity of key species in the community dominating the area affected by desalination discharge.


Assuntos
Antozoários/fisiologia , Ecotoxicologia/métodos , Purificação da Água/métodos , Animais , Recifes de Corais , Ecossistema , Oceano Índico , Compostos Organofosforados , Osmose , Salinidade , Água do Mar/química
12.
Sci Total Environ ; 639: 785-792, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29803049

RESUMO

This study investigates variables that shape coastal stakeholders' knowledge about marine ecosystems and impacts of seawater desalination. The influence of trans-situational and situation-specific variables on self-assessed and factual knowledge among coastal residents and commercial marine stakeholders. Data were collected using a questionnaire based survey administered to a random sample of coastal residents and commercial marine stakeholders in eight communities in central California. Knowledge of biological features was higher than knowledge of physical and chemical processes. Both trans-situational and situation-specific variables were significant predictors of knowledge, in particular gender, education, and ocean use patterns. TV and social media were the only information sources that correlated negatively with knowledge. Predictors for distinct types of knowledge were different and provide insights that could help target specific ocean literacy gaps. The study also finds that commercial marine stakeholders were more knowledgeable than other coastal residents. Having an economic stake in the marine environment appears to be a strong motivation to be more educated about the ocean.


Assuntos
Ecossistema , Salinidade , Água do Mar/química , California , Monitoramento Ambiental , Política Ambiental
13.
Vaccine ; 35(34): 4321-4329, 2017 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-28688781

RESUMO

BACKGROUND: Streptococcus pneumoniae is a leading cause of vaccine-preventable disease in children under 5years. Immunocompromised children and those with underlying diseases are at increased risk of severe complications from vaccine-preventable infections. We studied the humoral immune response to the 13-valent pneumococcal conjugate vaccine (PCV13) in children with HIV-infection, kidney or lung disease and compared this to the response in healthy control children. METHODS: Children aged 12-71months with underlying conditions including HIV-infection and those with kidney and lung diseases (at-risk children), and a healthy control group were vaccinated with PCV13. The at-risk children received two doses of PCV13 and the controls received one dose. Serotype-specific antibodies for all PCV13 serotypes were measured by a luminex-based enzyme immunoassay at baseline and post-vaccination. RESULTS: After the first PCV13 dose, the fold-increase in serotype-specific antibody geometric mean concentrations (GMCs) from baseline and the percentage of participants with ≥4-fold-increase in antibody concentrations was similar between the control and at-risk children. GMCs were, however, lower for three of the 13 serotypes in HIV-infected children, higher for serotype 6B in children with kidney disease and higher for serotypes 6B and 14 in children with lung disease. After second vaccine dose HIV-infected children had an increase in GMCs from post-first dose for nine serotypes but the percentage of participants with ≥4-fold-increase from baseline was similar post-second dose compared to post-first dose except for serotypes 6A and 19F. In children with kidney or lung diseases the immune responses after second vaccine dose were similar to post-first dose. Attenuated responses were observed for serotypes 3 and 19A in all study-groups, which was especially pronounced in the at-risk groups. CONCLUSION: All study-groups mounted an immune response to PCV13, with the at-risk groups having responses that were mostly similar to the control children.


Assuntos
Hospedeiro Imunocomprometido , Imunogenicidade da Vacina , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Criança , Pré-Escolar , Feminino , Infecções por HIV/complicações , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Imunidade Humoral , Imunização Secundária , Técnicas Imunoenzimáticas , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lactente , Nefropatias/imunologia , Pneumopatias/imunologia , Masculino , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/efeitos adversos , Sorogrupo
14.
Psychosom Med ; 79(8): 914-919, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28498275

RESUMO

OBJECTIVE: The potential influence of probiotic supplementation on cardiovascular health and stress responsivity remains largely unexplored. Some evidence suggests the possibility that probiotics may influence blood pressure. A separate body of research suggests that exaggerated cardiovascular reactions to acute psychological stress in the laboratory predict cardiovascular morbidity and mortality. The current investigation explored the effect of acute probiotic use on (1) resting cardiovascular measures in healthy young adults and (2) cardiovascular and psychological reactions to an acute psychological stressor in the laboratory. METHOD: Participants (N = 105, M [SD] age = 20.17 [1.26], 84.8% white) completed a 2-week, double-blind, and placebo-controlled trial of a multispecies and multistrain probiotic. Exclusion criteria included previous probiotic use, diagnosed gastrointestinal disorder, and/or current antibiotic use. At visits 1 and 2, participants completed the Paced Auditory Serial Addition Test, a widely used psychological stress task. Participants were randomly assigned to a probiotic blend or matched placebo. RESULTS: Compared with placebo, 2-week probiotic supplementation did not affect resting measures of cardiovascular function, cardiovascular responses during or recovery from stress, or psychological reactions to acute psychological stress. CONCLUSIONS: Contrary to expectations, short-term use of a probiotic supplement in healthy participants did not influence measures of cardiovascular function or responsivity to psychological stress. Future research is needed to determine species- and strain-specific effects of probiotics in healthy participants with various degrees of stress responsiveness, as well as in diseased populations.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Probióticos/farmacologia , Estresse Psicológico/fisiopatologia , Adolescente , Adulto , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Feminino , Seguimentos , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Probióticos/administração & dosagem , Adulto Jovem
15.
Exp Biol Med (Maywood) ; 242(1): 88-91, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28044466

RESUMO

Increased levels of oxidative stress have been suggested to play a detrimental role in the development of diabetes-related vascular complications. Here, we investigated whether the concentration of malondialdehyde, a marker of lipid oxidation correlated to the degree of aortic plaque lesions in a proatherogenic diabetic mouse model. Three groups of apolipoprotein E knockout mice were studied for 20 weeks, a control, a streptozotocin-induced diabetic, and a diabetic enalapril-treated group. Enalapril was hypothesized to lower oxidative stress level and thus the plaque burden. Both diabetic groups were significantly different from the control group as they had higher blood glucose, HbA1c, total cholesterol, low-density lipoprotein, very low-density lipoprotein, together with a lower high-density lipoprotein concentration and body weight. Animals in the diabetic group had significantly higher plaque area and plasma malondialdehyde than controls. The two diabetic groups did not differ significantly in any measured characteristic. In summary, there was a positive correlation between plasma malondialdehyde concentration and aorta plaque area in apolipoprotein E knockout. Even though further investigation of the role of lipid oxidation in the development of atherosclerosis is warranted, these results suggest that biomarkers of lipid oxidation may be of value in the evaluation of cardiovascular risk.


Assuntos
Apolipoproteínas E/genética , Diabetes Mellitus Experimental/fisiopatologia , Lipídeos/sangue , Placa Aterosclerótica/patologia , Animais , Aorta/patologia , Apolipoproteínas E/metabolismo , Colesterol/sangue , Diabetes Mellitus Experimental/genética , Enalapril/farmacologia , Metabolismo dos Lipídeos/genética , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Malondialdeído/sangue , Camundongos Knockout , Oxirredução , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/metabolismo
16.
Pediatr Infect Dis J ; 35(10): 1159-61, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27622688

RESUMO

Emphysematous pyelonephritis is a severe necrotizing infection of the kidneys characterized by gas formation within the parenchyma, the collecting system or the perinephric tissue. To our knowledge, there have only been 4 cases of this condition reported in children. We report 2 additional cases in children managed at Chris Hani Baragwanath Academic Hospital, Johannesburg, South Africa.


Assuntos
Enfisema , Pielonefrite , Pré-Escolar , Evolução Fatal , Feminino , Humanos , Lactente , Rim/diagnóstico por imagem , Rim/patologia , Radiografia Abdominal , Tomografia Computadorizada por Raios X
17.
Ann Bot ; 118(5): 941-955, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27451985

RESUMO

Background and aims Miscanthus is a genus of perennial C4 grasses native to East Asia. It includes the emerging ligno-cellulosic biomass crop M. ×giganteus, a hybrid between M. sinensis and M. sacchariflorus. Biomass yield and cold tolerance are of particular interest in Miscanthus, given that this crop is more temperate adapted than its C4 relatives maize, sorghum and sugarcane. Methods A plant exploration was conducted in eastern Russia, at the northern extreme of the native range for Miscanthus, with collections including 174 clonal germplasm accessions (160 M. sacchariflorus and 14 M. sinensis) from 47 sites. Accessions were genotyped by restriction site-associated DNA sequencing (RAD-seq) and plastid microsatellites. Key Results Miscanthus sinensis was found in maritime climates near Vladivostok (43·6°N) and on southern Sakhalin Island (46·6°N). Miscanthus sacchariflorus was found inland at latitudes as high as 49·3°N, where M. sinensis was absent. Most M. sacchariflorus accessions were diploid, but approx. 2 % were tetraploids. Molecular markers revealed little population structure (Jost's D < 0·007 among diploid groups) but high genetic diversity (expected heterozygosity = 0·14) within the collection of Russian M. sacchariflorus. Genome-wide association (GWA) analysis for traits measured at the collection sites revealed three M. sacchariflorus single nucleotide polymorphisms (SNPs) significantly associated with the number of stems per unit area, one with height and one with basal stem diameter; three were near or within previously described sorghum quantitative trait loci for related traits. Conclusions This new Miscanthus germplasm collection from eastern Russia will be useful for breeding Miscanthus and sugarcane cultivars with improved adaptation to cold. Moreover, a strategy is proposed to facilitate the rapid utilization of new germplasm collections: by implementing low-cost SNP genotyping to conduct GWA studies of phenotypic data obtained at collection sites, plant breeders can be provided with actionable information on which accessions have desirable traits and alleles.

18.
Front Plant Sci ; 7: 821, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27379120

RESUMO

Polyploidy is a common phenomenon in the evolution of angiosperms. It has been suggested that polyploids manage harsh environments better than their diploid relatives but empirical data supporting this hypothesis are scarce, especially for trees. Using microsatellite markers and flow cytometry, we examine the frequency of polyploids and diploids in a progeny trial testing four different populations of Acacia senegal, a species native to sub-Saharan regions of Africa. We compare growth between cytotypes and test whether polyploid seedlings grow better than diploids. Our results show that polyploids coexist with diploids in highly variable proportions among populations in Senegal. Acacia senegal genotypes were predominantly diploid and tetraploid, but triploid, pentaploid, hexaploid, and octaploid forms were also found. We find that polyploids show faster growth than diploids under our test conditions: in an 18 years old field trial, polyploid superiority was estimated to be 17% in trunk diameter and 9% in height while in a growth chamber experiment, polyploids grew 28% taller, but only after being exposed to drought stress. The results suggest that polyploid A. senegal can have an adaptive advantage in some regions of Africa.

19.
Ann Bot ; 117(7): 1229-39, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27192706

RESUMO

BACKGROUND AND AIMS: The C4 perennial grass miscanthus has been found to be less sensitive to cold than most other C4 species, but still emerges later in spring than C3 species. Genotypic differences in miscanthus were investigated to identify genotypes with a high cold tolerance at low temperatures and quick recovery upon rising temperatures to enable them to exploit the early growing season in maritime cold climates. Suitable methods for field screening of cold tolerance in miscanthus were also identified. METHODS: Fourteen genotypes of M. sacchariflorus, M. sinensis, M. tinctorius and M. × giganteus were selected and grown under warm (24 °C) and cold (14 °C) conditions in a controlled environment. Dark-adapted chlorophyll fluorescence, specific leaf area (SLA) and net photosynthetic rate at a photosynthetically active radiation (PAR) of 1000 µmol m(-2) s(-1) (A1000) were measured. Photosynthetic light and CO2 response curves were obtained from 11 of the genotypes, and shoot growth rate was measured under field conditions. KEY RESULTS: A positive linear relationship was found between SLA and light-saturated photosynthesis (Asat) across genotypes, and also between shoot growth rate under cool field conditions and A1000 at 14 °C in a climate chamber. When lowering the temperature from 24 to 14 °C, one M. sacchariflorus exhibited significantly higher Asat and maximum photosynthetic rate in the CO2 response curve (Vmax) than other genotypes at 14 °C, except M × giganteus 'Hornum'. Several genotypes returned to their pre-chilling A1000 values when the temperature was increased to 24 °C after 24 d growth at 14 °C. CONCLUSIONS: One M. sacchariflorus genotype had similar or higher photosynthetic capacity than M × giganteus, and may be used for cultivation together with M × giganteus or for breeding new interspecies hybrids with improved traits for temperate climates. Two easily measured variables, SLA and shoot growth rate, may be useful for genotype screening of productivity and cold tolerance.


Assuntos
Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Poaceae/fisiologia , Clorofila/química , Clorofila/metabolismo , Genótipo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Ploidias , Poaceae/genética , Temperatura
20.
Curr Diabetes Rev ; 12(4): 331-358, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26381142

RESUMO

Glucagon-like peptide-1 (GLP-1) has shown to influence the oxidative stress status in a number of in vitro, in vivo and clinical studies. Well-known effects of GLP-1 including better glycemic control, decreased food intake, increased insulin release and increased insulin sensitivity may indirectly contribute to this phenomenon, but glucose-independent effects on ROS level, production and antioxidant capacity have been suggested to also play a role. The potential 'antioxidant' activity of GLP-1 along with other proposed glucose-independent modes of action related to ameliorating redox imbalance remains a controversial topic but could hold a therapeutic potential against micro- and macrovascular diabetic complications. This review discusses the presently available knowledge from experimental and clinical studies on the effects of GLP-1 on oxidative stress in diabetes and diabetes-related complications.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Prática Clínica Baseada em Evidências , Exenatida , Peptídeo 1 Semelhante ao Glucagon/agonistas , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Humanos , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Peçonhas/farmacologia , Peçonhas/uso terapêutico
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