Decreased Pyruvate but Not Fatty Acid Driven Mitochondrial Respiration in Skeletal Muscle of Growth Restricted Fetal Sheep

Fetuses with intrauterine growth restriction (FGR) have impaired oxidative and energy metabolism, with persistent consequences on their postnatal development. In this study, we test the hypothesis that FGR skeletal muscle has lower mitochondrial respiration rate and alters the transcriptomic profiles associated with energy metabolism in an ovine model. At late gestation, mitochondrial oxygen consumption rates (OCRs) and transcriptome profiles were evaluated in the skeletal muscle collected from FGR and control fetuses. The ex vivo mitochondrial OCRs were reduced (p < 0.01) in permeabilized FGR soleus muscle compared to the control muscle but only with pyruvate as the metabolic substrate. Mitochondrial OCRs were similar between the FGR and control groups for palmitoyl-carnitine (fatty acid-driven) or pyruvate plus palmitoyl-carnitine metabolic substrates. A total of 2284 genes were differentially expressed in the semitendinosus muscle from growth restricted fetuses (false discovery rate (FDR) ≤ 0.05). A pathway analysis showed that the upregulated genes (FGR compared to control) were overrepresented for autophagy, HIF-1, AMPK, and FOXO signaling pathways (all with an FDR < 0.05). In addition, the expression of genes modulating pyruvate’s entry into the TCA cycle was downregulated, whereas the genes encoding key fatty acid oxidation enzymes were upregulated in the FGR muscle. These findings show that FGR skeletal muscle had attenuated mitochondrial pyruvate oxidation, possibly associated with the inability of pyruvate to enter into the TCA cycle, and that fatty acid oxidation might compensate for the attenuated energy metabolism. The current study provided phenotypic and molecular evidence for adaptive deficiencies in FGR skeletal muscle. © 2023 by the authors.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Improving boys' reading comprehension with readers theatre

Research on readers theatre has indicated that it can improve elementary students\u27 reading achievement and can be motivating, engaging and enjoyable, even for reluctant or struggling readers. Because of the potential for improvement and the engagement factor, the purpose of this study was to examine the effects of readers theatre on young male students, a population that tends to be more reluctant to read. This matched quasi‐experimental study examined the differential effects of readers theatre on second‐grade boys\u27 decoding, word knowledge and reading comprehension. Students were pretested and posttested using the Gates‐MacGinitie Reading Test. With the use ofa propensity score matching procedure, 46 students were matched from a sample of 76 on the basis of pretest scores, English‐language learner status, at‐risk status and whether the students received special education services. A repeated measures analysis of variance detected a time effect on the reading comprehension measure, which was qualified by an interaction effect, indicating that boys in the treatment group outperformed those in the business‐as‐usual comparison group. Implementing readers theatre in elementary classrooms may be an effective means for engaging young male students in the reading process and improving their reading comprehension. Additional implications for instruction, limitations and directions for future research are also discussed

Metais pesados em LATOSSOLO tratado com lodo de esgoto e em plantas de cana-de-açúcar Heavy metals in an Oxisol treated with sewage sludge and in sugarcane plants

A presença de metais pesados no lodo de esgoto constitui um dos maiores entraves para sua aplicação em solos agrícolas. Neste contexto, o presente trabalho teve como objetivos avaliar os efeitos de aplicações sucessivas de lodo de esgoto sobre o acúmulo de metais pesados num LATOSSOLO AMARELO Distrófico e em plantas de cana-de-açúcar e a fitodisponibilidade desses elementos através de extratores químicos. O experimento foi conduzido nos anos agrícolas 1996/97 e 1997/98 sendo que, no primeiro ano, além dos tratamentos calagem + adubação mineral e testemunha, foram aplicadas em área total, doses equivalentes a 33, 66 e 99 mg ha-1 (base seca) de lodo de esgoto. Em 1997/98 o lodo foi reaplicado em doses equivalentes a 37, 74 e 110 mg ha-1 (base seca). Foram detectados acúmulos de Cu, Cr, Ni e Zn na camada 0 0,2 m do solo. As concentrações de Cd, Cr, Ni e Pb nas amostras de plantas de cana-de-açúcar estiveram abaixo dos limites de determinação do método analítico empregado, porém, no caldo, a presença de Cd, Cr e Ni, esteve abaixo de 0,02 mg kg-1. Os teores de Cu e Zn nas várias partes da cana-de-açúcar não foram superiores aos limites normais de variação encontrados na literatura. As soluções extratoras apresentaram eficiência apenas na avaliação da fitodisponibilidade do Zn, determinado nas amostras de colmo e caldo, no ano agrícola 1997/98.<br>The concern about the presence of heavy metals in plants growing in soils treated with sewage sludge can be a restricting factor for the use of this waste in agriculture. The aim of this paper was to evaluate the possibility of heavy metal accumulation in an acid soil after two successive sewage sludge applications and the availability, using chemical extractants for a typic hapludox, of these metals to sugarcane plants. The experiment was managed during two years, 1996/1997 and 1997/1998, and had 5 treatments in a randomized block design: lime + mineral fertilization, control and sewage sludge applied at three levels, 33, 66 and 99 mg ha-1 in the first year and 37, 74 and 110 mg ha¹ in the second year. After two sewage sludge applications in the two year period an increase of the level of Cu, Cr, Ni and Zn in the topsoil (00.2 m layer) was observed. Levels of Cd, Cr, Ni and Pb in plant leaves were bellow detection limits. In sugarcane juice the levels of Cd, Cr and Ni were bellow 0.02 mg kg-1. Levels of Cu and Zn in leaves were not different from the usually reported values for plants cultivated in soils without sludge application. The chemical extractants used (0.1 mol L-1 HCl and Mehlich-3) removed more Cu, Ni and Zn from the soil than DTPA-TEA and all of them were effective only to preview Zn concentration in stalks and juice of ratton sugarcane