Chapter The Intertwined Chloroplast and Nuclear Genome Coevolution in Plants

Photosynthetic eukaryotic cells arose more than a billion years ago through the engulfment of a cyanobacterium that was then converted into a chloroplast, enabling plants to perform photosynthesis. Since this event, chloroplast DNA has been massively transferred to the nucleus, sometimes leading to the creation of novel genes, exons, and regulatory elements. In addition to these evolutionary novelties, most cyanobacterial genes have been relocated into the nucleus, highly reducing the size, gene content, and autonomy of the chloroplast genome. In this chapter, we will first present our current knowledge on the origin and evolution of the plant plastome in the different Archaeplastida lineages (Glaucophyta, Rhodophyta, and Viridiplantae), focusing on its gene content, genome size, and structural evolution. Second, we will present the factors influencing the rate of DNA transfer from the chloroplast to the nucleus, the evolutionary fates of the nuclear integrants of plastid DNA (nupts) in their new eukaryotic environment, and the drivers of chloroplast gene functional relocation to the nucleus. Finally, we will discuss how cytonuclear interactions led to the intertwined coevolution of nuclear and chloroplast genomes and the impact of hybridization and allopolyploidy on cytonuclear interactions

A influência da musicoterapia nos parâmetros hemodinâmicos de pacientes comatosos / The influence of music therapy on the hemodynamic parameters of comatose patients

1 INTRODUÇÃOA musicoterapia tem se destacado entre pesquisas por seus efeitos benéficos, sendo inserida cada vez mais como recurso terapêutico, sem contra-indicações, largamente favorecedora ao grupo de pacientes comatosos, afim de aumentar a capacidade do paciente captar estímulos sensoriais e melhorar o quadro clínico, além de reduzir a pressão arterial (PA), frequência cardíaca (FC), aliviar as dores e diminuir o estresse.2 OBJETIVO Analisar a influência da musicoterapia nos parâmetros hemodinâmicos de pacientes comatosos. 3 MÉTODOTrata-se de um estudo experimental com abordagem quantitativa/qualitativa. A amostra foi de dois pacientes, P1 e P2, do sexo masculino, com tempo de lesão de 3 meses, sendo P1 de 18 anos e P2 de 16 anos, ambos em coma por traumatismo crânio encefálico (TCE) internados na Unidade de Terapia Intensiva do Hospital Regional do Baixo Amazonas (HRBA).  O projeto foi aprovado pelo comitê de ética e pesquisa tendo como número 288.328, Campus XXII - Tapajós e permissão do (HRBA). Os familiares assinaram o Termo de Consentimento Livre e Esclarecido concordando com a participação do seu ente na pesquisa. Os instrumentos de avaliação foram: Ficha de anamnese sensorial para verificar o perfil musical do paciente de acordo com informações fornecidas pelos responsáveis; Ficha de Monitorização hemodinâmica para conferir a FC, PA, frequência respiratória (FR) e saturação de oxigêncio (Sp02) monitorizados antes, durante e após a realização da técnica. 4 RESULTADOSHouve uma diminuição nos valores da FC em ambos os pacientes, mas com relevância estatística (p<0.05, de acordo com o teste de Wilcoxon) apenas em P1 e uma estabilização na PA sistólica em ambos, porém somente P2 obteve valor relevante. Ocorreu redução no duplo produto em ambos com relevância estatística. Em relação a FR, houve redução dos valores após o atendimento, porém somente P2 teve relevância estatística. A SPO2 em ambos os pacientes apresentou valores aumentados após as 10 sessões, e estes valores foram considerados estatisticamente significantes. 5 CONCLUSÃOConclui-se que a musicoterapia se mostrou eficaz na melhora dos parâmetros hemodinâmicos de pacientes comatosos, vítimas de TCE

Small RNAs Reflect Grandparental Environments in Apomictic Dandelion

Plants can show long-term effects of environmental stresses and in some cases a stress “memory” has been reported to persist across generations, potentially mediated by epigenetic mechanisms. However, few documented cases exist of transgenerational effects that persist for multiple generations and it remains unclear if or how epigenetic mechanisms are involved. Here, we show that the composition of small regulatory RNAs in apomictic dandelion lineages reveals a footprint of drought stress and salicylic acid treatment experienced two generations ago. Overall proportions of 21 and 24 nt RNA pools were shifted due to grandparental treatments. While individual genes did not show strong up- or downregulation of associated sRNAs, the subset of genes that showed the strongest shifts in sRNA abundance was significantly enriched for several GO terms including stress-specific functions. This suggests that a stress-induced signal was transmitted across multiple unexposed generations leading to persistent changes in epigenetic gene regulation

Cytonuclear interactions remain stable during allopolyploid evolution despite repeated whole-genome duplications in Brassica

Several plastid macromolecular protein complexes are encoded by both nuclear and plastid genes. Therefore, cytonuclear interactions are held in place to prevent genomic conflicts that may lead to incompatibilities. Allopolyploidy resulting from hybridization and genome doubling of two divergent species can disrupt these fine-tuned interactions, as newly formed allopolyploid species confront biparental nuclear chromosomes with a uniparentally inherited plastid genome. To avoid any deleterious effects of unequal genome inheritance, preferential transcription of the plastid donor over the other donor has been hypothesized to occur in allopolyploids. We used Brassica as a model to study the effects of paleopolyploidy in diploid parental species, as well as the effects of recent and ancient allopolyploidy in Brassica napus, on genes implicated in plastid protein complexes. We first identified redundant nuclear copies involved in those complexes. Compared with cytosolic protein complexes and with genome-wide retention rates, genes involved in plastid protein complexes show a higher retention of genes in duplicated and triplicated copies. Those redundant copies are functional and are undergoing strong purifying selection. We then compared transcription patterns and sequences of those redundant gene copies between resynthesized allopolyploids and their diploid parents. The neopolyploids showed no biased subgenome expression or maternal homogenization via gene conversion, despite the presence of some non-synonymous substitutions between plastid genomes of parental progenitors. Instead, subgenome dominance was observed regardless of the maternal progenitor. Our results provide new insights on the evolution of plastid protein complexes that could be tested and generalized in other allopolyploid species

Síndrome de DiGeorge (deleção do cromossomo 22q11.2): manejo e prognóstico

A síndrome de DiGeorge (SDG), também conhecida como síndrome velocardiofacial, é uma condição neurogenética autossômica dominante de interesse global caracterizada pela microdeleção do cromossomo 22q11.2, na qual não há predileção por gênero ou raça. A doença é conhecida pela tríade clássica as cardiopatias congênitas, timo hipoplásico – ou aplásico – e hipocalcemia decorrente da hipoplasia paratireoidiana O diagnóstico da síndrome baseia-se em dois exames laboratoriais, a Hibridização Genômica Comparativa baseada em microarray (aCGH) e a Hibridização por Fluorescência in situ (FISH), ambas com a finalidade de investigar o distúrbio genético e o tratamento consiste em tratar as alterações decorrentes da patologia. O objetivo estudo é analisar o manejo e o prognóstico da síndrome de DiGeorge por meio de um apanhado de casos clínicos. Trata-se de uma revisão bibliográfica integrativa, de natureza quantitativa, que utilizou as plataformas PubMed (Medline), Scientific Eletronic Library On-line (SciELO) e Cochrane Library como bases de dados para a seleção dos artigos, todos na língua inglesa. Foram utilizadas literaturas publicadas com recorte temporal de 2017 a 2022. De acordo com as literaturas analisadas, foi observado que a SDG requer diligência por parte dos profissionais da saúde no que concerne ao seu manejo, vide os vários fenótipos, desde leves a graves, da patologia. Por ter envolvimento multissistêmico, é essencial que, mesmo antes do diagnóstico, os distúrbios inerentes à síndrome sejam tratados e sujeitos à suspeição por intermédio da equipe, a qual necessita ter conhecimento acerca dessa possibilidade, haja vista a eventualidade de um pior prognóstico aos pacientes portadores

Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

Minimal Symptom Expression' in Patients With Acetylcholine Receptor Antibody-Positive Refractory Generalized Myasthenia Gravis Treated With Eculizumab

The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension

Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study

BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (VT). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients.OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference.DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries.MAIN OUTCOME MEASURES: Women and men were compared with respect to use of LTVV, defined as VT of 8 ml kg-1 or less predicted bodyweight (PBW). A VT was deemed 'default' if the set VT was a round number. A mediation analysis assessed which factors may explain the sex difference in use of LTVV during intra-operative ventilation.RESULTS: This analysis includes 9864 patients, of whom 5425 (55%) were women. A default VT was often set, both in women and men; mode VT was 500 ml. Median [IQR] VT was higher in women than in men (8.6 [7.7 to 9.6] vs. 7.6 [6.8 to 8.4] ml kg-1 PBW, P < 0.001). Compared with men, women were twice as likely not to receive LTVV [68.8 vs. 36.0%; relative risk ratio 2.1 (95% CI 1.9 to 2.1), P < 0.001]. In the mediation analysis, patients' height and actual body weight (ABW) explained 81 and 18% of the sex difference in use of LTVV, respectively; it was not explained by the use of a default VT.CONCLUSION: In this worldwide cohort of patients receiving intra-operative ventilation during general anaesthesia for surgery, women received a higher VT than men during intra-operative ventilation. The risk for a female not to receive LTVV during surgery was double that of males. Height and ABW were the two mediators of the sex difference in use of LTVV.TRIAL REGISTRATION: The study was registered at Clinicaltrials.gov, NCT01601223